Commercial seeds are widely used for re-vegetation interventions in Mediterranean areas. This seeds mostly consist of species and varieties of non-local provenance. The current practice relies mainly on forage or turf and fast growing species, even if it is often inefficient. Twenty-two local populations or commercial varieties of annual and perennial species belonging to the botanical families Leguminosae, Graminaceae and Compositae, were evaluated in a four-year field experiment, in order to investigate their potential in terms of establishment and persistence in the re-vegetation of an inactive sand quarry. Native species showed better performances than commercial varieties and encourage further actions for the valorisation of local plant biodiversity. Among legumes, the best adapted species was the perennial Lotus cytisoides that showed high persistence in combination with other positive traits. A few annual species i.e. Melilotus indica, Trifolium subterraneum and Ornithopus sativus performed well and persisted until the end of the experiment. Among perennial grasses, Cynodon dactylon survived to drought and low soil nutrients. Both native annual grasses Lolium rigidum and Aegilops geniculata performed very well during the first two years of experiments. Both forbs, the perennial Cichorium intybus and the annual Chrysanthemum coronarium did not guarantee a satisfactory persistence. Some native species were evidenced, that may play an important role in the re-vegetation of sand quarries and have good potential to be further characterised before introduction in the seed market. This article is protected by copyright. All rights reserved.

Many studies have confirmed the validity of plant cover and organic farming in ameliorating soil quality. The goal of this study was to investigate the efficiency of rehabilitation practices, in a degraded soil ecosystem consisting of: i) organic or inorganic fertilization, and ii) presence or absence of almond trees.

The experiments were carried out for two years in the South of Italy in three fields characterized by different slope (0, 2 and 6%). Each field was split up into two parts, one assigned to organic fertilization and the other assigned to mineral fertilization, and planted with almond trees using GF677 or Franco rootstocks. The results showed that the organic fertilization, particularly in the presence of the Franco rootstock, resulted more effective in increasing soil organic matter content and microbial activity especially in the 0% and 2% slopes. However, in the 6% slope, where a lower soil metabolism was observed, an improvement of chemical and biochemical soil properties was generally evident for both fertilization systems. The Franco rootstock improved soil quality, maintaining a good production, whereas, the GF677, has exploited more soil resources, resulting in a higher growth and yield; therefore, the use of almond tree with Franco rootstock associated with organic matter application is a useful practice in order to preserve soil quality and to rehabilitate degraded soils. This article is protected by copyright. All rights reserved.

Soil quality (SQ) assessment from farmers’ point of view can be used as a primary indicator for planning sustainable agriculture. Despite this fact, limited information is documented with regard to SQ indicators e.g., weed species, crop types and management practices from farmers’ knowledge perspectives. The aims of this study are to analyze factors that determine farmers’ knowledge of SQ, identify SQ indicators of weed species and crop types across different SQ status, and assess soil-and-crop management practices that maintain SQ in the Mai-Negus catchment, northern Ethiopia. Fifty-two farmer household heads were chosen randomly for questionnaire interview. The results showed significant (P ≤ 0.05) differences in the proportion of respondents who used different crop-and-soil management practices. The success of overall prediction by the logistic regression model (model Chi-square = 0.84, P < 0.01) and level of model correct predictions (86%) indicated that the explanatory variables have sufficiently explained farmers’ knowledge of SQ indicators. Provided that other conditions remained constant, the odds ratio of variables such as farmer experience, access to information, farm location, education, field slope and land tenure have significantly increased the likelihood of farmers’ for being knowledgeable of SQ indicators. This study also demonstrated that most farmers are knowledgeable in identifying weed species, crop types and management practices across various SQ status, which suggests that such SQ indicators should be used to assess SQ status (degradation severity) while locating fields to be intervened using appropriate management strategies. This article is protected by copyright. All rights reserved.

Mining reclamation tries to reduce environmental impacts, including accelerated runoff, erosion and sediment load in the nearby fluvial networks and their ecosystems. This study compares the effects of topography and surface soil cover on erosion on man-made slopes coming from surface mining reclamation in Central Spain. Two topographic profiles, linear and concave, with two surface soil covers, subsoil and topsoil, were monitored for two hydrologic years. Sediment load, rill development, and plant colonization from the four profiles were measured under field conditions. The results show that, in the case of this experiment, a thick and non-compacted topsoil cover on a linear slope yielded less sediment than carbonate colluvium or topsoil cover on a concave slope. This study also shows that vegetation establishment, which plays an important role in erosion control, depends on topography. Plant cover was more widespread and more homogeneous on linear profiles with topsoil cover. On concave slopes, plant establishment was severely limited on the steepest upper part and favoured in the bottom. This study suggests that management of topography and surface soil cover should be approached systematically, taking three outcomes into consideration: i) topsoil can lead to a successful mining reclamation regardless of topography, ii) created concave slopes can lead to a successful mining reclamation, and iii) topography determines the vegetation colonization pattern. This article is protected by copyright. All rights reserved.

Desertification is one of the main environmental and also social and economic problems facing Iran. Seventeen out of 31 Iranian provinces, which are home to approximately 70% of the total population, are affected by Desertification. This study aimed to use GIS and fuzzy logic for mapping environmentally sensitive areas (ESAs) to desertification based on MEDALUS approach in Isfahan province, central Iran. Six desertification indicators including climate, soil, vegetation, soil erosion, groundwater, and management and policy quality were used to determine various types of ESAs to desertification. Seventeen desertification indices affecting the quality of each indicator were spatially mapped and assigned a value between 0 and 1 using fuzzy logic option of ArcSDM3 software in GIS environment. Results showed that a 21.7% of the study area was classified as critical, 70% as fragile, 5.5% as potential and 2.9% of the area was not affected by desertification. In the town of Borkhar 64.2% of the area was classified as critical, followed by the town of Isfahan and Nayin with 40.2%, 31.8%, respectively. Results at provincial scale indicated that the climate indicator and humidity index with a weighting mean of 0.71 and 0.77 were the most affective factors in the desertification of the study area. The developed model in this study can be used for mapping Desertification status in other 16 provinces which contain desert areas. These assessments provide a GIS-based desertification database which Iran as a member of UNCCD can use to report the condition of Desertification at national scale. This article is protected by copyright. All rights reserved.

Spanish mountains have been affected by the expansion of shrubs and forests since the mid-20th century. This secondary succession in vegetation has some positive effects, but also drawbacks, such as an increase in fire risk, loss of diversity in land use, a reduction in landscape and cultural value, less water available in river channels and reservoirs, constraints on livestock farming, a reduced number of local species and loss of biodiversity. This paper analyses the potential for grazing domestic goats to help control the spread of several species of shrubs such as the common broom (Cytisus scoparius), red raspberry (Rubus idaeus) and roses (Rosa sp.) that are commonly found in degraded pastures in the Cantabrian Mountains of northern Spain. Using experimental plots, the effects of two levels of stocking density (4·5 and 9 goats ha⁻¹ y⁻¹) are compared with other land management systems used in the region: burning, mechanical clearing and trimming. The combined use of goats with support from burning, clearing and trimming controls the spread of shrubs. The most efficient treatment was found with nine goats ha⁻¹ y⁻¹. Goat grazing also changes the distribution of shrubs, transforming a dense and continuous coverage into separate clumps and thereby enabling livestock to graze more easily. Maintaining a mixed structure of shrubs and pastures is the best treatment due to the low population density of the Cantabrian Mountains, as this enhances the biodiversity, controls fire risk and enriches the landscape; it also allows extensive livestock grazing as a main economic resource. Copyright © 2013 John Wiley & Sons, Ltd.

Under semiarid climatic conditions, intensive tillage increases soil organic matter losses, reduces soil quality, and contributes to climate change due to increased CO₂ emissions. There is a need for an agricultural management increasing soil organic matter. This paper presents the organic carbon (OC) and nitrogen (N) stocks, C:N ratio and stratification ratios (SRs) of these properties for olive groves soils under long-term organic farming (OF), and conventional tillage (CT) in Los Pedroches valley, southern Spain. The results show that OF increased C and N stocks. The soil organic carbon (SOC) stock was 73·6 Mg ha⁻¹ in OF and 54·4 Mg ha⁻¹ in CT; and the total nitrogen (TN) stock was 7·1 Mg ha⁻¹ and 5·8 Mg ha⁻¹ for OF and CT, respectively. In the surface horizon (A: 0–16·9 cm in OF and Ap: 0–21·8 cm in CT) and Bw horizon (16·9–49·6 cm in OF and 21·8–56 cm in CT), SOC and TN concentrations and C:N ratios were higher in OF than in CT. Soil properties stratification in depth, expressed as a ratio, indicates the soil quality under different soil management systems. The SR of SOC ranged from 2·2 to 3·1 in OF and from 2·1 to 2·2 in CT. However, only SR2 (defined by Ap-A/C) showed significant differences between CT and OF. The SR of TN showed similar trends to that of the SR of SOC. Organic farming contributes to a better soil quality and to increased carbon sequestration. Copyright © 2013 John Wiley & Sons, Ltd.

The establishment and growth of Rosmarinus officinalis L. under field conditions in two low-nutrient-content soils were evaluated, as well as the effect of arbuscular mycorrhizal (AM) fungi on essential oil production. The reclamation was conducted in two experimental sites: a limestone quarry and a wasteland soil, both surrounded by Mediterranean vegetation. Mycorrhizal R. officinalis plants inoculated with different AM fungal isolates were used to revegetate the sites. Pre-transplant inoculation with mycorrhizal fungi resulted in an increased survival of R. officinalis with similar results in both experimental areas. Mycorrhizal inoculation enhanced plant growth, increased essential oil yield and improved the establishment of plants under field conditions. The results indicate that the presence of the symbiosis can accelerate plant growth and alter the biosynthesis of secondary metabolites, thus improving the yield of medicinal plant extracts. It also confirmed the importance of selecting plant/symbiont combinations adapted to the environmental constraints of low-nutrient-content soils to design a successful application of mycorrhizal technology in marginal soils. Copyright © 2013 John Wiley & Sons, Ltd.

Although there is not a sole satisfactory methodology that applies universally up to now, aggregate stability has been proposed as an indicator of soil physical quality (SPQ). Difficulties persist when comparison of aggregate stability from different procedures are performed. The objective of this study is to evaluate appropriate aggregate stability methods that enable to distinguish the SPQ condition of both temperate and tropical medium-textured soils. Among different methods tested, results show that wet sieving using the well known fast wetting methods of Kemper & Rosenau and of Le Bissonnais rendered similar results in both environments. The mean weight diameter value of both methods for assessing aggregate stability can be considered as a dependable indicator of soil structure status for comparing soils. These aggregate stability methods are in correspondence with only one out of the eight SPQ indicators when entirely soils were used. It was concluded that the aggregate stability should be used judiciously and in concert with other indicators for an overall assessing of the SPQ condition. Copyright © 2013 John Wiley & Sons, Ltd.

This study aimed at surveying arbuscular mycorrhizal fungi (AMF) species and glomalin-related soil protein (GRSP) to understand their role as presumable biological indicators of soil quality in an undisturbed forest site (NT) and three sites with different management histories, soil textures, and different ages of recovery after reforestation for 20 (R20), 10 (R10) and 5 years (R05). Our objective was to determine how physical, chemical and microbiological soil attributes influence AMF species distribution, total-GRSP (T-GRSP) and easily extractable-GRSP (EE-GRSP). Glomus and Acaulospora were related to impacted sites, Gigaspora rosea to sites R10 and R20 that have different management histories and soil textures and Glomus geosporum to sites NT and R10, suggesting some influence of texture on its distribution. Scutellospora pellucida and other species were found only in one season. Correlations between EE-GRSP and T-GRSP on the one hand and total carbon and nitrogen, dehydrogenase and urease activity, microbial biomass carbon and microbial biomass nitrogen, on the other, reached values of 40–70% and were especially strong in summer. Soil bulk density had a negative and macroporosity a positive effect only on EE-GRSP, suggesting the necessity to choose either EE-GRSP or T-GRSP as biological indicator depending on the soil characteristics and management. This study demonstrates the effect of recovery age, seasonality and other soil attributes on AMF and GRSP distribution and shows that these biological attributes may be used as indicators of soil quality in the Atlantic forest in Brazil. Copyright © 2013 John Wiley & Sons, Ltd.

The Mediterranean region has been regarded as a critical hotspot for desertification due to the impact of soil degradation, the land-use changes and the climate variations. Few large-scale studies have been devoted to analyse trends in land sensitivity to desertification in the northern Mediterranean basin. The present paper contributes to this deserving issue by quantifying the level of land sensitivity to desertification in Italy at seven points between 1960 and 2010 at a fine spatial scale. The approach used followed the Environmentally Sensitive Area scheme that assesses changes in four key themes (climate, soil, vegetation and land management) related to land degradation processes. Italian land was classified into four levels of sensitivity to desertification (non-affected, potentially affected, fragile and critical) according to the Environmentally Sensitive Area framework. Interestingly, although land surface area classified as ‘fragile’ and ‘critical’ grew homogeneously in Italy between 1960 and 1990, the increase observed in the most recent time period was spatially clustered and contributed to reverse the polarisation in ‘structurally vulnerable’ and ‘non-affected’ regions observed in Italy. The paper discussed these trends in the light of socioeconomic changes that occurred in Italy after World War II. Copyright © 2013 John Wiley & Sons, Ltd.

Ecuador has the highest deforestation rate in South America, causing large-scale soil erosion. Inter-Andean watersheds are especially affected by a rapid increase of the population leading to the conversion of large areas of montane forest into pasture and cropland. In this study, we estimate soil erosion risk in a small mixed land-use watershed in the southern Andes of Ecuador. Soil loss was estimated at a spatial resolution of 30 m, using the Revised Universal Soil Loss Equation (RUSLE) where the RUSLE factors were estimated on the basis of limited public available data. Land-cover maps for 1976, 2008 and 2040 were created assuming increasing deforestation rates over the ensuing decades. Greater erosion rates are estimated for succession areas with agricultural cropland and pasture with maximum values of 936 Mg ha⁻¹ y⁻¹, where slopes and precipitation amounts are the greatest. Under natural forest vegetation, the estimated soil erosion rates are negligible (1·5 to 40 Mg ha⁻¹ y⁻¹) even at steep slopes and higher elevations where rainfall amounts and intensities are generally higher. When the entire watershed has undergone substantial deforestation in 2040, erosion values may reach 2,021 Mg ha⁻¹ y⁻¹. Vegetation cover is the most important factor for potential soil erosion. Secondary factors are related to rainfall (R-factor) and topography (LS factors). Although the spatial predictions of potential soil erosion have only limited meaning for erosion risk, this method provides an important screening tool for land management and assessment of land-cover change. Copyright © 2013 John Wiley & Sons, Ltd.

Monitoring soil erosion risk is an important part of soil conservation practices. It is usually estimated with the Universal Soil Loss Equation, and the C-factor (vegetation cover) is derived from optical satellite images. However, because of lack of data and resources, or in rapid assessments, C-factor is estimated using one or a few satellite observations, despite being temporally variable according to plants' phenology. The aim of this work was to study the effect of seasonality in estimating C-factor. This was achieved by demonstrating first that there is a difference when estimating soil erosion with Universal Soil Loss Equation at variable time steps in a year, namely once, seasonally and monthly. Using Moderate Resolution Imaging Spectroradiometer normalized difference vegetation index images and statistical analysis at subcatchment scale, it was shown that there is a significant difference when estimating mean annual soil loss with the aforementioned temporal options. The highest differences were observed between monthly and annual time steps. The second objective was to identify which is the optimum time to estimate C-factor in a year. The results show that November, October and March are the optimum months for single image estimation of annual soil erosion. Statistical analysis with a random point dataset suggested that the spatial variability of the results was influenced by the land cover type, especially in areas with variable leaf cover where a single date estimation of C-factor was not representative of the whole year, such as annual crops and deciduous trees. Copyright © 2013 John Wiley & Sons, Ltd.

Rangeland rehabilitation has multiple, sometimes conflicting goals, such as the reestablishment of the predisturbance vegetation, soil protection, and forage production. The rehabilitation techniques should be also cost-effective and practicable. Given the difficulties and high costs of restoring Succulent Karoo rangelands and the continuously high grazing pressure in the communal lands, tradeoffs should be accepted in the achievement of these goals. We tested the capability of paddock manure redistribution to reverse degradation trends in a heavily grazed Succulent Karoo rangeland in South Africa. Over 3 years, the effects of the manure application were compared with areas planted with mature shrubs as a benchmark for a predisturbance vegetation structure and with four popular rehabilitation techniques: (1) livestock exclusion; (2) brushpacking (coverage of dead shrubs); (3) mineral fertilizing; and (4) microcatchment construction. Manure was, besides planting, the only treatment that resulted in a significant increase in drought-resistant vegetation cover, but it compromised the dominance of native vegetation. In the manure plots, a pasture-like vegetation of non-native forage plants (which germinated mainly from seeds in the dung), developed (foremost Atriplex semibaccata). Manure application counteracted erosion as effectively as the planted shrubs and brushpacks. Expected negative side effects such as a decrease in plant species richness or salinization of topsoil were not detected. We also checked the potential of topsoil salinization by the halophytic A. semibaccata and found it to be low. For sites where a decrease in grazing pressure is unrealistic under current land tenure, redistribution of manure should be further explored to mitigate acute symptoms of degradation. Copyright © 2013 John Wiley & Sons, Ltd.

The continuous use of plowing for grain production has been the principal cause of soil degradation. This project was formulated on the hypothesis that the intensification of cropping systems by increasing biomass-C input and its biodiversity under no-till (NT) drives soil restoration of degraded agro-ecosystem. The present study conducted at subtropical [Ponta Grossa (PG) site] and tropical regions [Lucas do Rio Verde, MT (LRV) site] in Brazil aimed to (i) assess the impact of the continuous plow-based conventional tillage (CT) on soil organic carbon (SOC) stock vis-à-vis native vegetation (NV) as baseline; (ii) compare SOC balance among CT, NT cropping systems, and NV; and (iii) evaluate the redistribution of SOC stock in soil profile in relation to soil resilience. The continuous CT decreased the SOC stock by 0·58 and 0·67 Mg C ha⁻¹ y⁻¹ in the 0- to 20-cm depth at the PG and LRV sites, respectively, and the rate of SOC sequestration was 0·59 for the PG site and ranged from 0·48 to 1·30 Mg C ha⁻¹ y⁻¹ for the LRV site. The fraction of C input by crop residues converted into SOC stock was ~14·2% at the PG site and ~20·5% at the LRV site. The SOC resilience index ranged from 0·29 to 0·79, and it increased with the increase in the C input among the NT systems and the SOC sequestration rates at the LRV site. These data support the hypothesis that NT cropping systems with high C input have a large potential to reverse the process of soil degradation and SOC decline. Copyright © 2013 John Wiley & Sons, Ltd.

Recent rapid changes in global scale drivers of desertification, land degradation and drought (DLDD) have two important consequences for drylands. First, changes in these drivers, for example in food and energy prices, make improving interventions in drylands more urgent because of their potential impacts. Second, these changes introduce new knowledge gaps regarding both the potential impacts on social-ecological dryland systems and the design of options to take advantage of opportunities. This paper identifies the most salient research needs in DLDD in drylands brought on by global drivers. The question was addressed through an iterative stakeholder consultative forum. First, relevant global scale drivers were identified through a literature review and preliminary consultation. Next, stakeholders and experts were further consulted to identify research priorities given rise to by these drivers. Identified research priorities were as follows: (i) assessing impacts of rising prices on DLDD in mixed market and subsistence production contexts; (ii) assessing options and limits of agricultural modernisation on fragile lands; (iii) developing methods for assessing land-use trade-offs and mapping productive lands; (iv) modelling and participatory methods for monitoring and evaluating soil carbon sequestration; (v) developing policy frameworks to regulate impacts of investment on the environment and local livelihoods; (vi) participatory modelling for regional and local adaptation planning; and (vii) valuation of non-market land degradation outcomes including biodiversity loss. Concluding, we call for a forward-looking interdisciplinary drylands research agenda with an increased emphasis on governance to address these priorities. Copyright © 2013 John Wiley & Sons, Ltd.

Soils from central Brazil have been intensively used over the last decades because of the rapid conversion of savannas (Cerrado) into corn/soybean fields. The objective of this work is to study modifications in the physical properties of soils in the Rio Verde watershed, as a function of the land use time for agriculture, determined from classification of Landsat satellite images between 1980 and 2010. Soil samples were collected at surface (0–20 cm) and subsurface (20–40 cm) horizons for the different classes of land use time (<10, 10–20, 20–30, and >30 years). The following physical properties were measured: bulk density (BD), air permeability (K_a), penetration resistance (PR), microporosity (MI), macroporosity (MA), and total porosity (TP). Results showed a strong expansion with time of agriculture that occupied 35·3% (1980), 37·4% (1990), 51·3% (2000), and 60·9% (2010) of the watershed area. When properties were compared with those from the reference areas (preserved soils under native vegetation), significant differences were observed for all the physical attributes of soils for a land use time higher than 20 years. Overall, BD and PR increased with land use time, and the opposite was verified for K_a, MA, and TP. Some physical properties presented values (e.g., 1·54 g cm⁻³ for BD and 0.06 cm³ cm⁻³ for MA) close to the critical ones reported to affect crop development, but they were not still impacting on local soybean yield. Copyright © 2013 John Wiley & Sons, Ltd.

Land-use changes (LUCs) can be defined as the result of the direct action of the stakeholders in a particular area and natural or human driving forces. LUCs can influence various processes within the landscape and can have an impact on landscape functions. An analysis of the impact of LUCs on landscape processes can help to focus future rural policies. LUCs in Mediterranean areas particularly affect landscape functions because of their agro-pedoclimatical characteristics. The aims of this work are as follows: (i) to characterise LUCs in the last 11 years in a typical Mediterranean area, the Trasubbie river basin (southern Tuscany, Italy); (ii) to extrapolate these changes and create spatially explicit LUC scenarios for the near future; and (iii) to simulate how and where the predicted LUCs may affect soil redistribution. We carried out an analysis of LUCs within the study area and used the trends to propose alternative scenarios for 2013. For these years, we spatially allocated land use (using the Conversions of Land Use and its Effects model) and used a landscape process model (landscape process modelling at multi-dimensions and scales) to assess soil redistribution patterns. Land use in the study area changed almost linearly between 1996 and 2007, with cereals and annual fodder crops decreasing, and vineyards, perennial pastures and land abandonment increasing. Our LUC scenario extrapolates these dynamics to make predictions for 2013. A comparison of LAPSUS results between LUC and baseline scenarios for 2013 showed an increase in terms of net soil loss and total erosion, and a decrease in terms of sediment delivery ratio. Copyright © 2013 John Wiley & Sons, Ltd.

An exceptional rainfall and hydrological event occurred on 19–21 October 2012 in the central western Pyrenees and was particularly significant in the Upper Aragón River basin and its tributaries, mainly the Irati River. Analysis of historical records showed that, considered separately, the event of 19 and 20 October ranked between the second and fifth highest most extreme daily precipitation events. For the two days combined (with a total between 200 and 260 mm), the precipitation event was the most extreme 2-day event among all observation stations but one. The consequent flood destroyed part of an urban area, and a long stretch of a national road triggered landslides, enlarged the alluvial plain and caused generalised soil erosion in cultivated fields cropped with winter cereals. Badlands in the marls of the Inner Depression yielded high volumes of sediment. The floods in the tributaries were relatively moderate (return periods of 14–42 years), whereas in the Upper Aragón River, the flood corresponded to a return period of approximately 400–500 years and to 142 years at the end of the Yesa reservoir, although difficulties in estimating the discharge increased the uncertainty of these values. The Yesa and Itoiz reservoirs considerably reduced the intensity of the flood in the middle and lower Aragón River and confirmed the importance of the water level in the reservoirs when such rainfall events occur. The water storage in the Yesa reservoir increased from 16% to 53% as a consequence of the event. More integrated studies are necessary to decrease the risks associated with flood hazards. This is particularly the case in mountain areas, where the steep slopes and longitudinal gradients of the rivers shorten the concentration time of floods and increase the energy that erodes channels and riverbanks. Copyright © 2013 John Wiley & Sons, Ltd.

Soil conservation measures including cutoff drains, tree planting, Crops diversifications and destocking were implemented in Kondoa eroded area (KEA) for decades. This study assessed soil erosion changes in KEA and examined drivers of changes using Universal Soil Loss Equation, Geographic Information Systems and socioeconomic survey. Soil erosion was predicted by using data on soil, digital elevation model, rainfall and land use/cover visually interpreted from multitemporal satellite imageries. The predicted average soil erosions were 14·7, 23 and 15.7 Mg ha⁻¹y⁻¹ during 1973, 1986 and 2008, respectively. The area under very high soil erosion severity that was 30% in 1973, 26% in 1986 and 25% in 2008, whereas the area with high erosion severity was 26% in 1973 changed into 49% in 1986 and 2008 indicating recent stabilization. The area with moderate erosion increased from 15%, 16% and 18% during the same period. Field survey confirms a decrease of soil erosion in KEA compared with the past showing better soil conservation. Age of farmers, long-term adoption of conservation practices and on-farm tree planting were found to be the major factors contributing toward reduced soil erosion. Major limitations in soil conservation were poor mainstreaming of conservation activities on local production systems and lack of institutions promoting conservation at the community level. The study concluded that long-term conservation investment for restoration, protection and socioeconomic support contributes significantly in land rehabilitation in KEA. Copyright © 2013 John Wiley & Sons, Ltd.

The overall aim of the paper is the assessment of human-induced accelerated soil erosion processes due to forest harvesting in the Upper Turano River Basin. The spatio-temporal pattern of soil erosion processes was investigated by means of a spatially distributed modelling approach. We used the Unit Stream Power Erosion and Deposition model. During the soil erosion-modelling phase, the forest cover changes were mapped via remote sensing. According to this operation, the forest sectors exploited for timber production amounted to about 2781 ha or 9·9% of the wooded surface from March 2001 to August 2011. In this period, the average annual net soil erosion rate estimated by means of modelling operations totalled 0·83 Mg ha⁻¹ y⁻¹ for all the forest lands. The net soil erosion rate predicted for the disturbed forest lands is significantly higher than the average value for the entire forest (5·34 Mg ha⁻¹ y⁻¹). Estimates indicate a soil loss equal to 8521 Mg y⁻¹ (net soil erosion 0·34 Mg ha⁻¹ y⁻¹) in the undisturbed forest area (254 km²), whereas the 27·8 km² of disturbed forest area could potentially lose 14 846 Mg y⁻¹. The paper shows that a disturbed forest sector could produce about 74·2% more net erosion than a nine times larger, undisturbed forest sector. Copyright © 2013 John Wiley & Sons, Ltd.

Proxy conflicts involving local revolutionaries and external forces during the Cold War years caused major damage to the physical landscapes and soils of South East Asia. Using a series of small case studies, this paper assesses some of these impacts of war on the geodiversity of the Lao PDR, and upon some other environmental values and ecosystem services that are dependent upon physical landforms that host or facilitate them. Satellite imagery and ground-based surveys indicate that even after nearly four decades, bomb craters remain discernible at densities that commonly exceed 200/km² and in some cases exceed 800/km². This landform damage also implies major loss of soil capital, full recovery from which is likely to take millennia. Very significant damage was also caused by military engineering projects. The results of this study confirm the severe, widespread and long-term nature of the environmental damage that can be inflicted by war. They also demonstrate the potential utility of forensic geomorphology as a tool in the investigation of potential environmental war crimes. Copyright © 2013 John Wiley & Sons, Ltd.

In the Sahelian region, the high precipitation intensity and the daily rainfall extreme values are currently the main cause of soil erosion and land degradation. In addition, solid transport often leads to reservoir siltation and reduction of the amount of water available for agriculture. To cope with these issues, Soil and Water Conservation (SWC) measures have been regularly employed in the Sahelian area. However, a proper cost-effectiveness analysis of the impact of SWC interventions on the catchment sediment budget normally requires quantitative surveys on erosion and sedimentation processes. Where data for calibration and validation of models are scarce, an overall methodology to evaluate the economical sustainability of a proposed intervention can be of paramount importance. The study herein proposed aims to assess the monetary sustainability of SWC measures in limiting the reservoir siltation of the Laaba dam (Yatenga District, Northern Burkina Faso). In particular, the catchment sediment budget was estimated by means of morphological and pedologic parameters and dam sedimentation rates; a cost-effectiveness analysis was then performed to assess the economic sustainability of a possible SWC intervention. The proposed methodology showed interesting potentials for land and water management in Burkina Faso, particularly when data and financial resources are limited and where the application of detailed process-based models is not possible. Copyright © 2013 John Wiley & Sons, Ltd.

Soil organic carbon (SOC) is one of the important measures of soil fertility and sustainability in arable lands. With continuous CO₂ flux measurements, this study assessed the SOC decomposition and its environmental controls at both half-hourly and season-long scales in a single-crop rice (Oryza sativa L.) paddy during three fallow periods between 2004 and 2007. Measurements were made on a gray lowland soil sited in eastern Japan using the eddy covariance method. Ecosystem respiration was strongly affected by soil water content measured at 0–0·1 m depth. At 0·5 m³ m^− 3 or more of soil water content, the baseline of ecosystem respiration decreased by 50% compared with that at 0·2 m³ m^− 3 . The effect was quantified at half-hourly scale using an empirical multiple regression model, together with the soil surface temperature and the time after residue incorporation. At season-long scale, net biome production, which is equivalent to the change in the SOC pool during the fallow period, was estimated from the flux and ancillary data at 150 g C m^− 2 in 2004–2005, 70 g m^− 2 in 2005–2006, and 270 g C m^− 2 in 2006–2007. Apparently, as much as 46 to 79% of the soil organic matter incorporated (crop residues, ratoon, and stable manure) was decomposed during the fallow period. Precipitation, or associated soil water content, was important for the carbon balance of the field at season-long scale because of its large interannual variability and relatively low permeability of the paddy soil. Copyright © 2013 John Wiley & Sons, Ltd.

In this paper, the Annualized Agricultural Non-Point Source (AnnAGNPS) model has been used to estimate runoff, peak discharge and sediment load at the event scale in a Mediterranean watershed. The study area is the Carapelle torrent, Southern Italy (area = 506 km²), where continuous rainfall, streamflow and sediment load data are available. Nineteen flood events have been registered in the period 2007–2009 and were used for the application of the model.

The aim of the paper is to evaluate the predictive accuracy of the model at the event scale, in a medium-size watershed, given the specific conditions of the semi-arid environments. A sensitivity analysis has been carried out to assign the correct parameterization: the mean normalized output variation of the most meaningful input parameters pointed out the influence of the curve number on runoff, peak discharge and sediment load predictions (values greater than 1); the MN Manning's roughness coefficient and K, C and P factors of the universal soil loss equation showed a moderate influence on sediment load simulations (values between 0·5 and 1).

The selection of the Soil Conservation Service synthetic storm types has been based on the observed storm events analysis to improve the peak discharge simulations. The model prediction has proved to be good for runoff (R² = 0·74, NSE = 0·75, W = 0·92) and peak discharge (R² = 0·85, NSE = 0·70, W = 0·94), and satisfactory for sediment yield (R² = 0·70, NSE = 0·63, W = 0·91). The relative error is lower for high events; this result is quite interesting in semi-arid environments, where most of the annual sediment yield is concentrated in a few, severe events. Copyright © 2013 John Wiley & Sons, Ltd.

Karst rocky desertification (KRD) is a type of land degradation especially prominent in southwest China. This article analyzes the anthropogenic driving forces of KRD at two scales: rural locality and its macro socio-economic circumstances. At the rural locality scale, the intensive human pressure on land because of a large and fast growing population and unsustainable land use are identified to be the reason for KRD. However, more radical driving forces lie in the farmers' disadvantages in social-economic circumstances, which compel them to overuse rural land. Hukou system, coastal development strategy, and household responsibility system are verified as three important factors in social-economic circumstances. At last, a two-scale framework is constructed to explain how anthropogenic driving forces lead to KRD in southwest China. Copyright © 2013 John Wiley & Sons, Ltd.

Frankincense from Boswellia papyrifera forest (BPF) is a traded commodity used in the pharmaceutical, food, cosmetic and chemical industries. Ethiopia is an important producer of frankincense, but the resource is under continuous degradation and requires conservation. We applied a contingent valuation to assess rural households' willingness to pay and willingness to contribute labor for BPF conservation. Next to the bid, willingness to pay is influenced most by income, education, and willingness to contribute labor by family labor and gender of the household head. A household is willing to pay at least $4·86 or contribute 7·17 labor days per year, which amounts to $6·64 at per capita daily income. This suggests that using per capita daily income rather than market wage rates could result in convergence in response asymmetry of labor and cash payment vehicles. The potential local demand for conservation of BPF could be mobilized effectively with complementary policy interventions aimed at sustainable use and poverty reduction. Copyright © 2013 John Wiley & Sons, Ltd.

The interaction between land use/cover change and landscape pattern is pivotal in research concerning global environmental change. This study uses three different Landsat images of 1989, 1998 and 2009 to study the land use/cover and landscape pattern changes in the middle reaches of the Tarim River basin. envi®, erdas®, ArcGIS® and fragstats® software were used to analyse the land use/cover changes. The objectives of study were to map and study the changes in land use/cover and landscape pattern, and propose some possible factors in making the land use/cover changes from 1989 to 2009. Seven different types of land use/cover are analysed, and the results are listed in tables. From 1989 to 1998, the percentage of farmland, slight–moderate saline land, heavy saline land and water areas have increased; woodland, desert and the undeveloped land have decreased. From 1998 to 2009, farmland, heavy saline land and the undeveloped land have increased; the other types of land use/cover have decreased. The gravity centre of each land use/cover types has shifted. The farthest shifting of the gravity centre was heavy saline land, which occurred between 1989 and 1998. The transformation and changes of land use/covers and landscape occurred more frequently from 1989 to 2009. Other types of land use and land cover changes to saline land have increased, which implied that a serious salinization took place in the Tarim Basin. The results from this study would show the adverse environmental changes (e.g. salinization and desertification) and they can be used for future sustainable management of land resources. Copyright © 2013 John Wiley & Sons, Ltd.

Sustainable development based on economic growth that is environmentally sound is increasingly essential. To achieve both ecological and social progress without detracting from China's primary economic objectives, China's Ministry of Communications has promoted the strategy of harmonious road systems, for which artistic principles are incorporated in the road's design to balance the needs of the environment with those of socioeconomic development without neglecting human esthetic needs. To illustrate the new strategy's impact, we examined a project that has been conducted following this approach in the Shennongjia region of China's Hubei Province since 2004. As in the use of ecological corridors, the new strategy emphasizes the need to decrease the impact of road construction on plant and animal habitats by emphasizing the protection of existing natural habitats and the use of local species for revegetation of the land surrounding the roads. However, it also emphasizes the need to improve traffic safety, promote local tourism and economic growth, and provide a demonstration to citizens (including bureaucrats) of the need for environmental protection both during and after road construction. After 6 years of monitoring, we found that the new strategy both satisfies the human desire for beauty and improves the road's harmony with nature and the surrounding visual landscape while promoting environmental conservation, ecotourism, traffic safety, socioeconomic development, and cultural values. This approach will help to guide future landscape design, planning, and management. Copyright © 2013 John Wiley & Sons, Ltd.

State-of-the-art predictive models of soil organic carbon (SOC) dynamics associated with land use changes are unable to reflect the diversity of tropical soil types as the knowledge of contrasting site-specific factors in mediating the response of the SOC pool is sparse. This paper examines the influence of soil type and management on SOC dynamics following the conversion of forests to annual cropping in Ghana. Soil from primary forests and from areas with short (2–7 years) and long (20 years) histories of maize cultivation was sampled from a Vertisol dominated by smectite and Ultisol dominated by kaolinite. Wet sieving was used to separate soil fractions below and above 250 µm. SOC concentrations and δ¹³C signatures of SOC in soil fractions and bulk soil were determined. SOC stocks were calculated by the commonly used fixed depth approach and by the equivalent soil mass approach. After 20 years of cultivation of the Vertisol, the total SOC content was 40 per cent lower than under forest, and about 95 per cent of the forest-derived SOC had been lost. After 20 years of cultivation of the Ultisol, total SOC content was only about 20 per cent lower than under forest and merely 30 per cent of the forest-derived SOC had been lost. Both soil types were managed as they would typically be in small scale farming systems, thus the higher SOC losses and the substantial loss of forest-derived SOC from the Vertisol question the conventional concept of smectite having a higher SOC-stabilizing potential than kaolinite under field conditions. Copyright © 2013 John Wiley & Sons, Ltd.

The lower Himalayan regions of north-west India experienced a severe land-use change in the recent past. A study was thus conducted to assess the effect of grassland, forest, agricultural and eroded land uses on soil aggregation, bulk density, pore size distribution and water retention and transmission characteristics. The soil samples were analysed for aggregate stability by shaking under water and water drop stability by using single simulated raindrop technique. The water-stable aggregates (WSA) >2 mm were highest (17·3 per cent) in the surface layers of grassland, whereas the micro-aggregates (WSA < 0·25 mm) were highest in eroded soils. The water drop stability followed the similar trend. It decreased with the increase in aggregate size. Being lowest in eroded soils, the soil organic carbon also showed an adverse effect of past land-use change. The bulk density was highest in eroded lands, being significantly higher for the individual aggregates than that of the bulk soils. The macroporosity (>150 µm) of eroded soils was significantly (p < 0·05) lower than that of grassland and forest soils. The grassland soils retained the highest amount of water. Significant (p < 0·05) effects of land use, soil depth and their interaction were observed in water retention at different soil water suctions. Eroded soils had significantly (p < 0·05) lower water retention than grassland and forest soils. The saturated hydraulic conductivity and maximum water-holding capacity of eroded soils were sufficiently lower than those of forest and grassland soils. These indicated a degradation of soil physical attributes due to the conversion of natural ecosystems to farming system and increased erosion hazards in the lower Himalayan region of north-west India. Copyright © 2013 John Wiley & Sons, Ltd.

The aim of this study was to investigate the effectiveness of compost and vermicompost as soil conditioners in alleviating salt-affected soils and increasing maize productivity. A greenhouse trial, consisting of seven soil amendment treatments in a completely randomized design with three replications, was carried out at Khon Kaen University, Thailand, during the rainy season of 2011. Plant height and total dry matter of maize increased in treatments with compost and vermicompost application when compared with the control (no fertilizer) in two types of soils (saline and nonsaline) during the growing season. Soil pH and electrical conductivity in saturation paste extracts were decreased by compost and vermicompost amendments with or without earthworms when compared with unamended treatments in the saline soil. Compost and vermicompost amendments improved cation exchange capacity, soil organic carbon, total nitrogen and extractable phosphorus in both soils. These amendments also increased exchangeable K⁺, Ca²⁺ and Mg²⁺ while decreasing exchangeable Na⁺ in the saline soil, which suggested that Ca²⁺ was exchanged for Na⁺, exchangeable Na⁺, then leached out, and soil salinity reduced as a result. Soil microbial activities including microbial C and N and basal soil respiration were improved by the application of compost and vermicompost amendments with or without earthworms when compared with the control in both soils. This experiment showed that the compost and vermicompost were effective in alleviating salinity and improving crop growth. Copyright © 2013 John Wiley & Sons, Ltd.

This study investigated dip-tank use effects on the surrounding woody vegetation cover and encroachment level and on their indigenous utilisation. Eight dip tanks, three in deep-pale-brown old alluvium sandy, three in deep-yellow-red loamy, and two in rock outcrops and stony ground soils, were selected. Woody vegetation survey was conducted at 50, 100, 150, 300, 500, 700 and 900 m from each dip tank. Dichrostachys cinerea and Acacia tortilis were the dominant woody species in all areas. In deep-pale-brown old alluvium sandy soils, D. cinerea density was affected by distance from dip tank up to 150 m (p = 0∙03), where the density of A. tortilis was low (p = 0∙02). In deep-yellow-red loamy soils, the lowest and highest (p = 0∙05) D. cinerea densities were recorded at 150 and 700 m from the dip tank, respectively. Inconsistent results were found on the piosphere formation of total woody density and cover. Nevertheless, large areas surrounding the dip tank had a bush cover of >50 per cent. This study concluded that there was heavy bush encroachment around many dip tanks despite the harvest for woody species by the community. Therefore, there is a need to develop a sustainable and integrated bush control programme that provides conservation plans for species valuable for food and livelihood security. The programme should be based on communal participation and consider shifting of old dip-tank sites and protecting the areas from disturbance. Indiscriminate (burning) or selective (manual) or a combination of the two bush control methods may be initially recommended after a rest period of at least two consecutive growing seasons. Copyright © 2013 John Wiley & Sons, Ltd.

Studies on molecular characterization of soil organic carbon (SOC), although critical to understanding SOC dynamics, are relatively scarce for reclaimed minesoils. The aim of this study was to assess the effects of time since reclamation on SOC molecular properties in a reclaimed minesoil chronosequence using different spectroscopic indices. The chronosequence consisted of four minesoils, with similar soil-forming conditions, reclaimed to pasture ecosystem, and distinguished only by time since reclamation varying from 1 to 22 years. Results indicated that the SOC molecules in the older minesoils were comprised of highly humified polyaromatic and polycondensed species with higher proportions of O-containing and N-containing functional groups. In each minesoil, resistant and labile SOC fractions were identified. The resistant SOC fraction constituted >20 and <10 per cent of total SOC (g kg⁻¹) in the oldest and youngest minesoil, respectively. Among the spectroscopic indices, the ε₂₈₅ ultraviolet-visible index, diagnostic of aromatic C, was the most efficient in identifying the intrasite short-term (1-year) changes in SOC molecular properties. Strong positive relationships found between different spectroscopic indices and total SOC (g kg⁻¹), with consistently higher r² values observed in older minesoils, indicated that SOC molecular characteristics played a key role in overall SOC dynamics, becoming more influential with increasing time since reclamation. In addition, significant relationships between the spectroscopic indices and different soil quality parameters indicated that SOC molecular properties influenced soil quality as well. Overall, the results indicated that SOC molecular properties were useful indicators of both SOC dynamics and soil quality in this minesoil chronosequence. Copyright © 2013 John Wiley & Sons, Ltd.

Land degradation on officially ‘reclaimed’ opencast coal-mine sites is a widespread problem in South Wales. This project explores methods suitable for use by community volunteers seeking to effect local environmental improvement by restoring geoecological self-sustainability on lands that are commonly affected by extreme auto-compaction and low soil nutrient status. This paper describes a formally established 7-year experiment designed to assess the effect of three alternative tree planting strategies used in the forestation of such lands. These are notch planting (e.g. forestry), pit planting (e.g. parks and gardens) and trench planting (e.g. orchard terraces). The study explores tree survival and growth for two species commonly used in land reclamation contexts: alder [Alnus glutinosa (L.) Gaertn] and Welsh or Durmast Oak [Quercus petraea (Matt.) Liebl]. t-testing of the results shows that survival and growth rates for both species tend to be significantly better for trench planting than for pit planting than for notch planting. Differences in mortality between pit-planted and trench-planted trees become less significant during the experiment while differences in growth increase with time. The conclusion is that providing a loosened, lower density, rooting substrate significantly improves both the growth and the survival rates of trees planted in compacted Welsh surface coal-mine spoils and that trench planting is more effective than parks and gardens-style pit planting, which is more effective than forestry-style notch planting. Copyright © 2013 John Wiley & Sons, Ltd.

Better understanding of how the loess soils respond to topography and land use under catchment-scale vegetation restoration is needed to enable science-based land management interventions for the policy-driven “Grain-for-Green” eco-restoration program in the Loess Plateau of China. The objective of this study was to characterize the relationships of four selected soil quality indicators to land use under vegetation restoration and topography for a small catchment (0·58 km²) in the Loess Plateau. The major land uses established in the catchment are cropland, fallow (i.e., natural revegetation), grassland, and jujube orchard. The four soil quality indicators were soil organic carbon (SOC), soil total nitrogen (STN), soil total phosphorus (STP), and mean root zone soil water content during the wet season (MRZSWwet). SOC, STN, and MRZSWwet were significantly different (p < 0·05) for different land uses. Grassland showed the highest values for these three properties, whereas cropland had relatively low values for SOC and STN. Land use had no effect on STP, although the lowest value was observed in grassland. Spatial analysis showed that various relations between soil quality indicators and topography (slope and elevation) were observed. These relations were generally weak for most of them, and they varied with land uses. Further analyses indicated that land uses, slope, and elevation had significant effects on the relations between different soil quality indicators. The results here should provide useful information for the further development of “Grain-for-Green” program. Copyright © 2012 John Wiley & Sons, Ltd.

This study provides evidence that Miconia calvescens has the potential to accelerate surface erosion in stands where it invades by (i) reducing under-canopy light levels, thereby reducing the establishment of ground cover vegetation, and (ii) producing highly erosive throughfall drops on large leaves in a single-layer canopy. The throughfall energy in a stand of invasive miconia on the Island of Hawai‘i (USA), assessed by measuring the drop size and drop velocity distributions with a laser disdrometer, was significantly higher than that in a stand of native ‘ōhi‘a (Metrosideros polymorpha) and ambient rainfall. Median throughfall drop size for miconia (3·83 mm) was twice that of ambient rainfall (1·62 mm). Highly erosive throughfall resulted from large drops forming on large miconia leaves and relatively high fall velocities associated with the single-story miconia canopy. In contrast, multi-storied natural ‘ōhi‘a had a larger median drop size; however, a lower fall height reduced throughfall effective kinetic energy. Furthermore, the effective kinetic energy for miconia was high because large drops (> 3·8 mm) with high kinetic energy accounted for 60 per cent of the total energy (versus 30–40 per cent for other vegetation types). Consequently, unit kinetic energy of throughfall was 28 J m⁻² mm⁻¹ under miconia, compared with <24 J m⁻² mm⁻¹ for rainfall and <20 J m⁻² mm⁻¹ under ‘ōhi‘a. These data, combined with the observation of limited protective ground cover under miconia, show the potential for accelerated erosion occurring on forest floors in stands of invasive miconia. Copyright © 2012 John Wiley & Sons, Ltd.

Open-cast mining reclamation strategies are focused on the identification of the environmental factors at different scales that facilitate the vegetation establishment and development. Here, we characterised the environmental factors at macro-scale and micro-scale that influenced the herbaceous richness and biomass accumulation patterns trough a 32-year chronosequence. Herbaceous richness and biomass were influenced at macro-scale by successional and soil development gradients whereas at micro-scale by shrub cover and coarseness gradients. Indeed, certain environmental factors at macro-scale and micro-scale contributed simultaneously to determine these gradients. Explicitly, the successional gradient was related to carbon and nitrogen ratio, grazing intensity and Shannon diversity. Across this successional gradient, total herb biomass and Fabaceae biomass were reduced as well as main taxonomical groups richness. Soil development gradient was related to total nitrogen, pH and erosion severity. This gradient only influenced species richness and produced a richness reduction when pH and erosion severity increased. At micro-scale, the shrub cover gradient was related to organic matter thickness, producing a Poaceae biomass and bryophytes cover increase when shrub cover and organic matter increased. The coarseness gradient was related to the cover of rocks and bare soil, producing a reduction of herb biomass and richness when rocks and bare soil increased. These results emphasise the need to incorporate in the management plans the influence of soil development, successional, shrub cover and coarseness gradients over herbaceous richness and biomass to improve mine reclamation strategies. Copyright © 2012 John Wiley & Sons, Ltd.

Ash can provide valuable soil protection. However, ash is also very mobile, and soil protection patterns can be quickly changed, favouring the protection of some areas and exposing others with implications for soil erosion. In this research, the effects of a high severity wildfire on ash thickness were studied, 1 and 15 days after the fire. For this evaluation, several interpolation methods were tested to identify the best spatial predictor of ash distribution. The results showed that 1 day after the fire, ash was thinner in high severity areas. Fifteen days after the fire, ash thickness decreased, and the spatial pattern changed. This implies that evaluation of fire severity based on ash thickness must take a place immediately after the fire because it is affected by (re)distribution. There was an increase in the spatial autocorrelation, and ash distribution corresponded to a specific spatial pattern, because of wind (re)distribution. One day after the fire, the most accurate predictor was Inverse to a Weight 3 (IDW3) that detected easily the small-scale variability of ash thickness, and after 15 days, ordinary kriging identified a specific pattern of ash distribution. Copyright © 2012 John Wiley & Sons, Ltd.

The aim of this study was to investigate the main factors that influence smallholders' adoption decision of soil conservation measures in the Gedeb watershed. Data from 498 household heads who live in the three districts of the watershed were analysed using the binary logistic regression model. We find that farmers need adequate cash to invest in soil conservation measures. Moreover, farmers would be more encouraged to implement soil conservation measures when they have larger areas of cropland. We explore the possibility that when farmers presume that they have fertile land, they exploit their land more. This hints at the need for extension advice about the benefit of sustainable use of farmers' cropland so that they can maintain their land and pass it on to the future generation. Farmers' awareness about the benefit of land management practices and recognition of the problem erosion is causing on their crop land are central to their decision to adopt soil conservation measures. Furthermore, to adopt these measures, farmers have to be convinced about the effectiveness of these measures. Thus, awareness creation and demonstration of the effectiveness of these measures is essential. Because of the transboundary nature of the problem, policy makers in downstream countries that are suffering from the off-site impact (e.g. Sudan) would benefit from the information provided and support efforts in the implementation of soil conservation measures. Copyright © 2012 John Wiley & Sons, Ltd.

Soil degradation by deforestation and introduction of exotic grasses is a grave consequence of land-use change in tropical regions during the last decades. Soil restoration following natural succession (i.e., passive restoration) is slow because of low tree establishment. Introduction of tree plantings by human intervention (i.e., active restoration) results in a promising strategy to accelerate forest succession and soil recovery in tropical region. The present research was carried out to explore the restoration of soil properties after cattle exclusion and of grazing combined with native tree planting introduction (legumes and nonlegumes) in a tropical pasture in Veracruz, southeast Mexico. Results indicate that land-use changes decreased soil C and N pools in both litter and mineral soil. In addition, soil heterogeneity increased by land-use changes at both temporal and spatial scales. In the short term, passive succession (i.e., cattle exclusion) favors the recovery of C and N content in labile soil pools, indicated by the increase in litter C and N masses as well as C and N concentrations in soil microbial biomass. Soils under active restoration showed trends to recover the N cycling, such as a greater accumulation of N in litter, in soil total N concentrations, soil microbial biomass N concentrations, rates of net N transformations, and extractable water and microbial biomass C:N ratios mainly under legumes species. Active restoration including legume introduction is a key factor for rapid recovery of soil fertility. Copyright © 2012 John Wiley & Sons, Ltd.

Historical documentary sources from two regions with contrasting historical and social development were examined for information about landslide occurrence and characteristics. The archive search was complemented with limited field work to acquire information about the degree of recent landslide activity and land use. The results from two study areas (Ústí nad Labem in North Bohemia and Zlín in East Moravia) show considerable differences in the types of historical documentary source, their availability and the information they record. It is concluded that local newspapers that include special sections focusing on regional events are the best data sources for the landslide study. The reliability of the acquired historical landslide occurrence frequencies is generally not very good, but it does show notable regional differences caused by not only the availability of documentary sources but also the dynamics of the natural processes responsible for the landslide events. A reconstruction of the landslide activity during the last 70 or more years was carried out for selected sites. The reconstruction showed that the occurrence of historical landslides is only rarely respected in recent land use within both studied urban areas. Historical landslide information could be well used for site-specific landslide hazard assessment. Nevertheless, the use of this information to construct a historical landslide database on the regional or country level is limited only to certain regions of the Czech Republic. Copyright © 2012 John Wiley & Sons, Ltd.

Progress in combating aeolian desertification (land degradation resulting from wind erosion) has been achieved in an agro-pastoral ecotone of northern China since the mid-1980s. This paper reviews three common measures used to combat and control aeolian desertification in such regions. In addition, it introduces a case study on the recovery of a degraded semi-arid ecosystem to provide regional lessons and support theoretical and practical approaches to desertification prevention and reversal on a global scale. On the basis of the analysis and evaluation of three kinds of typical measures and one regional scale case, this study shows that human-caused aeolian desertified land can be rehabilitated. Although the technologies and management of combating aeolian desertification in an agro-pastoral ecotone of northern China still need further improvement through more experimentation and practical application in the future, the experience gained to date contains important lessons for the recovery of degraded land on a global scale. Copyright © 2012 John Wiley & Sons, Ltd.

Accurate and cost-effective mapping of karst rocky desertification (KRD) is still a challenge at the regional and national scale. Visual interpretation has been utilised in the majority of studies, while an automated method based on pixel data has been investigated repeatedly. An object-based method coupling with support vector machine (SVM) was developed and tested using Enhanced Thematic Mapper Plus (ETM+) images from three selected counties (Liujiang, Changshun and Zhenyuan) with different karst landscapes in SW China. The method supports a strategy of defining a mapping unit. It combined ETM+ images and ancillary data including elevation, slope and Normalized Difference Vegetation Index images. A sequence of scale parameters estimation, image segmentation, training data sampling, SVM parameters tuning and object classification was performed to achieve the mapping. A quantitative and semi-automated approach was used to estimate scale parameters for segmenting an object at an optimal scale. We calculated the sum of area-weighted standard deviation (WS), rate of change for WS, local variance (LV) and rate of change for LV at each scale level, and the threshold of the aforementioned index that indicated the optimal segment level and merge level. The KRD classification results had overall accuracies of 85·50, 84·00 and 84·86 per cent for Liujiang, Changshun and Zhenyuan, respectively, and kappa coefficients are up to 0·8062, 0·7917 and 0·8083, respectively. This approach mapped six classes of KRD and offered a visually appealing presentation. Moreover, it proposed a conceptual and size-variable object from the classification standard of KRD. The results demonstrate that the application of our method provides an efficient approach for the mapping of KRD. Copyright © 2012 John Wiley & Sons, Ltd.

In this paper, we studied the spatial variability of soil organic C (SOC), inorganic N (SIN) and extractable P (P_extr) in a grazed Mediterranean-type vegetation formation. Sampling was conducted from a gently sloping area in northern Greece.. The grazing pressure was evenly distributed over the experimental area with the exception of an overgrazed passage zone 200–300 m from steeper foothills. Soil samples, from the upper 10 cm, were collected every 10 m along four replicate lines (400 m length with a distance of 10 m between lines). Sampling took place twice (October and February). Data were analysed by geostatistical tools, and spherical models were significantly fitted to the semivariograms. SOC in both samplings and SIN in the first one displayed moderate spatial dependence which indicates the non-random distribution of their concentration. On the contrary, P_extr and SIN in winter exhibited weak spatial dependence, whereas P_extr in autumn showed spatial independence. For the parameters exhibiting spatial pattern, two scales of dependence were revealed: a fine scale within distances shorter than 10 m and a coarse scale varying between 80 and 130 m. The coarse distribution of SOC, SIN and P_extr invoked interplay among more predictable (composition of vegetation) and unpredictable (leaching, runoff) extrinsic factors, occurring at the landscape level. Specifically, SOC as a storage agent exhibited uniform spatial pattern in both samplings. By contrast, SIN by being susceptible to leaching exhibited time-specific dependence, whereas P_extr which was affected by surface runoff displayed limited or even spatial independence. Copyright © 2012 John Wiley & Sons, Ltd.

During the last few decades, land use changes have largely affected the global warming process through emissions of CO₂. However, C sequestration in terrestrial ecosystems could contribute to the decrease of atmospheric CO₂ rates. Although Mediterranean areas show a high potential for C sequestration, only a few studies have been carried out in these systems. In this study, we propose a methodology to assess the impact of land use and land cover change dynamics on soil organic C stocks at different depths. Soil C sequestration rates are provided for different land cover changes and soil types in Andalusia (southern Spain). Our research is based on the analysis of detailed soil databases containing data from 1357 soil profiles, the Soil Map of Andalusia and the Land Use and Land Cover Map of Andalusia. Land use and land cover changes between 1956 and 2007 implied soil organic C losses in all soil groups, resulting in a total loss of 16·8 Tg (approximately 0·33 Tg y⁻¹). Afforestation increased soil organic C mostly in the topsoil, and forest contributed to sequestration of 8·62 Mg ha⁻¹ of soil organic C (25·4 per cent). Deforestation processes implied important C losses, particularly in Cambisols, Luvisols and Vertisols. The information generated in this study will be a useful basis for designing management strategies for stabilizing the increasing atmospheric CO₂ concentrations by preservation of C stocks and C sequestration. Copyright © 2012 John Wiley & Sons, Ltd.

Conservation agriculture (CA) is often promoted as a set of cropping practices to reduce soil erosion and maintain soil fertility, while decreasing production costs and increasing crop yields. However, CA adoption is extremely low in Africa. Most investigations on constraints of its adoption leave out (i) the characteristics of CA as an emerging innovation and (ii) the wider institutional context. A comprehensive self-assessment tool for a systematic evaluation of factors influencing the CA adoption process at the field, farm and regional scale in a variety of regional contexts in Africa is still lacking. In an attempt to fill this knowledge gap, this article presents the motivation, development and testing of a Qualitative expert Assessment Tool for CA adoption in Africa (QAToCA) and its application. QAToCA is directed to regional experts, research teams and managers of development projects with a focus on CA, and allows them to assess their CA activities along a systematic, expert-based list of questions and criteria. Specifically, it aims at assessing the adoption potential of CA under the varied agro-ecological, socio-economic, cultural and institutional conditions of Africa as well as the specific supporting and hindering factors influencing this process.

As an example, its application in Kenya and Tanzania identified a relatively high CA adoption potential. The following factors, however, are noticed to require further improvement: accessibility of markets for CA products and inputs; adaptation of machinery and seeds to the CA practices; introduction of quality implementation measures; and a renewed motivation (interest) among CA service providers. Copyright © 2012 John Wiley & Sons, Ltd.

Cartographic analysis of the hazard of erosion is a useful tool for the planning and management of natural parks, helping to establish measures for protection and correction. Such parks, which offer spectacular landscape views and natural beauty, must be conserved with all their resources. Accordingly, park managers must have the cartographic tools for hazard planning, which is necessary for the rational and sustainable handling of human activities and the establishment of preventive and corrective measures. The present work describes a cartographic procedure using GIS that determines the risk of aeolian erosion. The method was applied to two protected natural parks in the central mountain system in Spain. This cartographic method revealed a weak risk of hazard of erosion in low-lying areas or valley floors, with increasing risk in areas of deflation. These areas were explored by mapping geomorphological domains and slopes, characterising different surficial deposits: colluvium, piedmonts, debris cone, alluvial fans and river terraces. Aeolian erosion on cultivated surfaces with gentle slopes was observed to be low, but in sectors with little agricultural activity and undulated reliefs, the hazard of erosion is important owing to the high analytical and textural erodibility and scant vegetation cover of these sectors. These parameters were studied on the basis of the mapping of soils and soil profiles. Additionally, the cartography of vegetation and the wind index in the cartographic procedure allowed for the different degrees of aeolian erosion to be better quantified. Copyright © 2012 John Wiley & Sons, Ltd.

The purpose of this study is to relate soil properties affected by the deposit of materials by the wind to the percentage of vegetation surface that facilitates their accumulation. To do this, we applied artificial wind and compared its effects to natural conditions by making use of the ‘fertility islands’ generated by some species of bushes under their canopies in semiarid environments and, which according to many publications, modify soil characteristics substantially.

Two very common species in our flat semiarid study area, Hammada articulata and Artemisia barrelieri, were chosen for comparison. Soil was sampled in gaps between shrubs and under canopies. Some shrubs were subjected to extra wind, whereas others were kept under natural conditions. At the end of this first stage, the islands under the canopies were sampled again, and any differences found in the data were studied. Increased retention of material affects the fertility of soils. Thus, we observed, for example, an increase in biomass carbon showing greater biological activity. Finally, we performed a statistical analysis, which resolved our hypothesis on the influence of the percentage of plant surface on the soil parameters. Copyright © 2012 John Wiley & Sons, Ltd.

A study was conducted to examine the responses of microbial activity and nitrogen (N) transformations along an altitudinal gradient. The gradient was divided into three parts. Three areas were sampled: upper part (UP): coniferous forest, corn field, and abandoned corn field; middle part (MP): tropical cloud forest, grassland, and corn field (COL); and lower part (LP): tropical deciduous forest and sugarcane. The results showed that soil microbial biomass carbon (C) and basal respiration were significantly higher in MP and UP than in LP, whereas the microbial quotient (C_mic/C_org) was higher in LP and MP than in UP. The metabolic quotient (qCO₂) was similar among gradient parts evaluated. Net N mineralization, ammonification, and nitrification rates were higher in UP than MP and LP. We found that in UP, the forest conversion to cropland resulted in no significant differences in microbial activity and N transformation rates between land uses. In MP, microbial biomass C, ammonification, and net N mineralization rates decreased significantly with conversion to cropland, but C_mic/C_org and nitrification were higher in COL. Basal respiration and qCO₂ were significantly lower in COL when compared with other land uses. In LP, lower microbial biomass C, C_mic/C_org, and nitrification rates but higher ammonification and net N mineralization rates were observed in tropical deciduous forest than in sugarcane. No significant differences in basal respiration and qCO₂ were found between uses of LP. Clearly, then, soil organic C is not equally accessible to the microbial community along the gradient studied. Copyright © 2012 John Wiley & Sons, Ltd.

To date, neither the method nor diagnostic indices employed in Cuba to evaluate erosion of Red Ferralitic or Ferrasol Rhodic soil in karstic regions has taken into consideration morphogenesis in such geo-ecosystems or their relationship with erosion, which has led to sequential degradation of the most productive soils in Cuba. We explore the case for considering A + B horizon depth as one of the basic indices for evaluating the severity of erosion. There is no methodology available for estimating the volume of soil lost through karstic absorption forms (dolines). This article forecasts loss of soil cover using a model which estimates losses of 268·52 to 450·52 mm y⁻¹ for future scenarios (periods of 25 and 50 years). A mean loss rate of 1·07 mm y⁻¹ was found in areas cultivated as pastureland during the period from 1986 to 2009, which exceeds the tolerance thresholds proposed by the Universal Soil Loss Equation and the soil formation rates estimated for limestone in Cuba and it is likely there is with a marked tendency for this to increase. These results should be interpreted as a first estimate for setting loss tolerances as there is no similar experience with own data for a more precise definition of the erosion of soil in karstic regions. Copyright © 2012 John Wiley & Sons, Ltd.

Physical damage is one of the main factors that cause seedling mortality in many ecosystems. However, the impact of physical damage due to rainfall erosion on seedling mortality is seldom investigated. In this study, we ask the following question: how does rainfall erosion influence seedling damage and establishment in the Loess Plateau region of China? Seedling damage and establishment experiments under different patterns of simulated rainfall were conducted. The seedling damage rate, damage type and growth status were investigated. The seedling damage rate was influenced by rainfall intensity and duration and by the runoff volume. The mean damage rate of all three studied species did not exceed 15 per cent, and the highest damage rate of individual species under special rainfall events was approximately 30 per cent. The type of damage suffered by the seedlings of Sophora viciifolia (which produces large seeds) mainly took the form of striking down, whereas seedlings of Artemisia scoparia (which produces small seeds) suffered the highest rates of washing away among the three studied species. In the seedling establishment experiment, after 120 days with six rainfall events, S. viciifolia had the highest seedling establishment rate (80·1 ± 2·5 per cent), followed by Bothriochloa ischaemun (67·2 ± 2·2 per cent), and A. scoparia (28·1 ± 2·5 per cent). The seedling damage rate, damage type and establishment rate were also related to seed size. Whether physical damage to seedlings is a major factor limiting vegetation restoration in eroded environments requires further research. Copyright © 2012 John Wiley & Sons, Ltd.

The effects of soil bunds on runoff, losses of soil and nutrients, and crop yield are rarely documented in the Central Highlands of Ethiopia. A field experiment was set up consisting of three treatments: (i) barley-cultivated land protected with graded soil bunds (Sb); (ii) fallow land (F); and (iii) barley-cultivated land without soil bund (Bc). For 3 years (2007–2009), the effect of soil bunds on runoff, losses of soil and nutrients, and crop productivity was studied. Daily runoff and soil and nutrient losses were measured for each treatment using standard procedures while barley yield was recorded from the cultivated plots. The results showed that Sb brought about significant reduction in runoff and soil losses. Plots with Sb reduced the average annual runoff by 28 per cent and the average annual soil loss by 47 per cent. Consequently, Sb reduced losses of soil nutrients and organic carbon. However, the absolute losses were still high. This implies the need for supplementing Sb with biological and agronomic land management measures to further control soil erosion. Despite these positive impacts on soil quality, Sb do not increase crop yield. Calculated on a per-hectare basis, Sb even reduce crop yield by about 7 per cent as compared with control plots, which is entirely explained by the reduction of the cultivable area by 8·6 per cent due to the soil bunds. Suitable measures are needed to compensate the yield losses caused by the construction of soil bunds, which would convince farmers to construct these land management measures that have long-term beneficial effects on erosion control. Copyright © 2012 John Wiley & Sons, Ltd.

Investigations were made of plant and soil responses to severe degradation through heavy grazing and browsing in arid, succulent, subtropical thicket. Severe degradation of thicket is of major concern in terms of threatened biodiversity, unsustainable utilization and collapse of other ecosystem services. We used a natural, field contrast, case-study approach, sampling within plots under lightly and heavily stocked conditions. Mean plant species diversity and richness did not change significantly at sample plot level although there was a 27 per cent decline in richness with degradation at the scale of the study site. On degraded plots, there was a high species turnover and high beta diversity, which created a replacement zone rather than an impoverished zone. Replacement species were confirmed as mainly, but not exclusively, weedy annual grasses and alien forbs. The few persisting perennials were small trees that survived above the browse line, and hardy shrub species. Perennial persisting and replacement species below the browse line may suggest potential candidates for restoration. Nitrogen was the only measured nutrient that showed a significant decrease with degradation. Phosphorous, potassium and magnesium increased significantly, with the first two mentioned reaching potentially excessive levels. Soil salinization occurred with an order of magnitude increase in sodium. Thus, the increased cation exchange capacity occurred together with development of a nutrient imbalance. The elevation in some nutrients and soluble salts is ascribed to wind-determined directional grazing that concentrate livestock in the degraded area. The implications of the above altered soil conditions for thicket restoration need to be further explored. Copyright © 2012 John Wiley & Sons, Ltd.

The extent of heathland decline is well documented in countries of the north and west of Europe, not so in southern European countries. In this paper, temporal changes produced in wet heathlands of Erica ciliaris and Erica tetralix in the last 26 years in NW Spain were analysed. Thirteen wet heathlands that had been studied in 1980 were again sampled in 2006. Plant species composition, cover, diversity, surface area occupied and soil pH were analysed in each sampling site. The results obtained showed changes in the management of almost all the sampling sites and in their surrounding area, with an increase in non-traditional practices (afforestation, repeated burning) with respect to 1980, resulting in a general decrease in the surface area occupied by these communities. A decrease of the woody cover and, as a result, an increase in the herbaceous cover was observed. Species richness did not show significant changes, but the identity of the species changed, with 73·9 per cent of the exclusive species of these communities declining or disappearing in favour of non-exclusive species. The pH values remained within the normal ranges for these communities, although a slight decrease was recorded. It was concluded that traditional management (cutting, grazing, sporadic burning) favoured the conservation of these ecosystems, with non-severe effects on the vegetation, and this should be noted by conservation planners. Management of the surrounding area should also be controlled to enhance preservation of these landscapes. Copyright © 2012 John Wiley & Sons, Ltd.

Hydrological extremes are major weather related disasters, but little is known about their long-term patterns in the context of environmental change. Better understanding of damaging rainfall (e.g. rainfall-erosivity events) occurring at different time-scales has important implications for hydrological and land degradation management. The study of the interdecadal variations may help in understanding some of the consequences of abrupt environmental changes over long time periods. Thus, a decadal-scale rainfall erosivity model (DREM), comparable with the Revised Universal Soil Loss Equation (RUSLE), was developed based on a parsimonious interpretation of rain aggressiveness (95th percentile of rainfalls). The DREM was parameterised to capture interdecadal erosivity variability at the Ukkel station (Belgium), which has the longest RUSLE-based rain-erosivity series in Europe (1898–2007). The DREM performed well against decadal RUSLE data, with a coefficient of determination (R²) of 0·72 and a Nash–Sutcliffe efficiency index of 0·71. The model outperformed three well-established models used in this study (R² ~ 0·4). For a spatial evaluation of the DREM, a pattern of decadal rainfall erosivity was provided for an area around Ukkel, which includes the western part of Germany bordering Belgium, and was compared with maps from the RUSLE approach for 1961–1990. The 95th percentile of June–September rainfalls proved to be a better predictor of decadal rainfall erosivity than yearly based precipitation amount. These results lay the foundation for estimating decadal erosivity in the surrounding areas of Ukkle as well as for historical reconstructions where detailed hydrological data are unavailable, and assumptions cannot be met, for physically based models. Copyright © 2012 John Wiley & Sons, Ltd.

The aim of this study was to examine the influence of land cover changes on soil organic carbon (SOC) and soil total nitrogen (STN) in the Daqing Prefecture of China, where heavy industrialisation in the form of dense oil wells has impacted the environment. Time-series presentations for the period 1978 to 2008 of remotely sensed data and soil survey data were used to assess the extent of the changes. The study revealed soil degradation under all land cover types and in all soil types, grassland retreat (−15 per cent), swampland retreat (−45 per cent) and increases in the area of farmland (+19 per cent), sand land (+1450 per cent) and alkaline land (+52 per cent). Depletion of the SOC pool occurred in swampland (−64 per cent) both because of the decrease in the area of swampland and because of a decrease in SOC density (−34 per cent). An increase in the SOC pool occurred in alkaline land because of the increase in the area and also because of an increase in SOC density (+297 per cent), but there was little change in the SOC pool in farmland because the increase in area was largely offset by a decrease in SOC density (−14 per cent). The decrease in the STN pool was substantial (−44 per cent), with the largest contributor being the decrease in swamplands (−74 per cent), partly because of the decrease in the area of swampland and partly because of a decrease in STN density (−52 per cent). Large decreases in the STN pool also occurred in farmland (−22 per cent) and grassland (−41 per cent). The direct impacts of construction associated with the expansion of the oil industry were overshadowed by indirect impacts such as interference with water flows and water levels resulting in salinisation of soil. The study also revealed that land cover changes are much more dynamic than a simple analysis would reveal, and because of lag times in the loss of SOC, soil degradation will continue even if land cover changes cease. Copyright © 2012 John Wiley & Sons, Ltd.

Grazing intensity and bush encroachment are disturbance factors that may alter the floristic composition of herbaceous species. This paper investigates impacts of grazing (intensity) and bush encroachment on herbaceous species and rangeland conditions in Borana, southern Ethiopia. Herbaceous species richness and the abundance of each species were greater in the light- and moderate-grazed areas than heavy-grazed sampling plots. Similarly, herbaceous species richness was highest at an intermediate level of biomass and seems to decline as biomass increases. Among a total of 40 herbaceous species recorded, 20 per cent were tolerant of grazing, whereas the remaining 80 per cent were highly susceptible to heavy grazing. In both encroached and non-encroached sampling plots, species richness varied from three to six species 0·25 m⁻². Overall, herbaceous species richness and abundance, in relation to grazing gradient, might disclose a better picture of the effect of grazing on individual herbaceous species. As species richness seems to decline under heavy grazing intensity, low to intermediate grazing levels may promote and conserve key forage species in savanna grazing lands. Copyright © 2012 John Wiley & Sons, Ltd.

In the present work, land cover and land use changes between 2003 and 2008 were assessed in the Cupatitzio River sub-basin located in the Trans-Mexican Volcanic System and Balsas Depression in Mexico. The effects of land cover conversion from temperate forest to avocado orchards on soil properties were determined. Land cover and land use databases were built for the years 1975, 2003, and 2008 using available cartographic information and interpretation of panchromatic SPOT images for the year 2008. Additionally, soil sampling was carried out in 16 representative sites in the higher parts of the sub-basin, where avocado plantation dynamics have caused important changes in areas covered by temperate forests. Results show that (i) temperate coniferous and tropical low deciduous forests were reduced at an annual rate of 0·9 per cent (1, 001 ha y⁻¹) between 1975 and 2008; (ii) cropland areas expanded at an annual rate of 0·7 per cent between 1975 and 2008, representing a growth of 553 ha y⁻¹; (iii) wet soil aggregate stability, mechanical resistance to penetration and nitrate (N-NO₃) concentration in the topsoil layer of Andosols were significantly affected by land use conversion to avocado orchards. Other soil properties such as organic matter, interchangeable K, and available P showed degradation tendencies. These results suggest the importance of implementing strategies for mitigating the accelerated process of transformation and degradation of natural resources in the Cupatitzio River sub-basin. The implementation of programs for deforestation reduction should be a priority in the restoration strategy. Copyright © 2012 John Wiley & Sons, Ltd.

Land use practices and vegetation cover distribution are considered to be the most important dynamic factors that influence the land degradation or the soil erosion of a region. In this study, a Soil Protection Index (SPI) is defined as a function of land use practices and intensity of vegetation cover. This index is used to map the relative degree of protection of topsoil from being eroded by external effects such as rainfall and overland flow. A fuzzy rule-based model integrated within ArcGIS® has been set-up and tested with the aim to develop SPI maps. The amount of vegetation cover distribution, that is, Normalized Difference Vegetation Index as proxy parameter and Land Use–Land Cover map are chosen as fuzzy input parameters for the SPI as the desired system output. The approach was tested in the Upper Awash basin in Ethiopia. The output SPI map was qualitatively evaluated against the expert-defined land degradation risk class, and it was found that locations that are mapped with ‘low and very low’ SPI classes at different time periods of the year have a high potential land degradation risk. Furthermore, socio-economic data (‘population and livestock densities’) and environmental parameters (‘altitude and soil erodibility’) for the region are used to correlate with the SPI map as an indirect method of evaluation. It is found that population and livestock density explained 68 per cent of the spatial distribution pattern of predicted SPI and an adjusted R-squared value of 0·681 (p < 0·05) was obtained. It was also found that the SPI distribution over the region for two different time periods, that is, January and July 2001, correlated positively (R² = 0·41 and R² = 0·51) with the soil erodibility of the region. The transferability and applicability of the model for different environmental settings or landscapes were tested by mapping the SPI of Italy. This SPI map of Italy was compared with the soil erosion map of Italy produced by the European Soil Bureau. It can be concluded that the SPI map reflects the potential land degradation risk distribution of the case-study region. Results show that a fuzzy rule-based model can provide useful preliminary information even without detailed and precise data information for developing appropriate strategies for land degradation assessment vital for sustainable land use management. Copyright © 2012 John Wiley & Sons, Ltd.

The goal of China's sloping land conversion programme (SLCP) is to combat soil erosion and to reduce rural poverty. An ex-ante assessment of possible SLCP impacts was conducted with a focus on rural sustainability, taking the drought-prone region of Guyuan in Western China as an example. The Framework for Participatory Impact Assessment (FoPIA) was used to conduct two complementary impact assessments, one assessing SLCP impacts at regional level and a second one assessing alternative forest management options, to explore possible trade-offs among the economic, social and environmental dimensions of sustainability. Regional stakeholders assessed the SLCP to be capable of reducing soil erosion but felt it negatively affected rural employment, and a further continuation of the Programme was advocated. Assessment of three forest management scenarios by scientists showed that an orientation towards energy forests is potentially beneficial to all three sustainability dimensions. Ecological forests had disproportionate positive impacts on environmental functions and adverse impact on the other two sustainability dimensions. Economic forests were assessed to serve primarily the economic and social sustainability dimensions, while environmental impacts were still tolerable. The FoPIA results were evaluated against the available literature on the SLCP. Overall, the assessment results appeared to be reasonable, but the results of the regional stakeholders appeared to be too optimistic compared with the more critical assessment of the scientists. The SLCP seems to have the potential to tackle soil erosion but requires integrated forest management to minimize the risk of water stress while contributing to economic and social benefits in Guyuan. Copyright © 2012 John Wiley & Sons, Ltd.

Improving our understanding of abiotic and biotic thresholds that are transgressed during ecosystem degradation is vital for effective landscape-level restoration. Establishing logical and consistent typologies of degradation is an important first-step in this process. Areas of degraded alpine meadow in western China are referred to as Heitutan (or ‘black soil beach’) and cover vast areas. Previously, four classes of grassland degradation have been differentiated in this large area: non-degraded alpine meadow and moderate, severe and extreme Heitutan. We evaluated existing field-based classifications of Heitutan in the Sanjiangyuan region, and examined the criteria on which these classifications are made, by using multivariate statistical approaches. First, we asked whether existing qualitative classifications, based on vegetation cover and the abundance of impalatable plant species, adequately describe the nature of degradation at different locations. We then used a suite of vegetation and soil measures collected across 175 sites spanning a range of degradation conditions to develop a new quantitative assessment of degradation across the alpine meadows of the Qinghai-Tibetan Plateau. Hierarchical classification highlights two broad classes of degradation: non-degraded alpine meadow and degraded Heitutan. The non-degraded category effectively combines the non-degraded grassland and moderate classes, whereas the degraded Heitutan combines the severe and extreme Heitutan classes. Ordination analyses suggest that the four previously recognized classes of degradation intergrade. Of the 14 biophysical variables used to classify subsites on the basis of their degradation, bare ground area and vegetation cover are the two most useful predictors of grassland condition and associated ecological threshold conditions. Copyright © 2012 John Wiley & Sons, Ltd.

Vineyards represent one of the most erosion-prone types of cultivated land. Because of this, cultivation practices are very important in reducing the soil erosion risk in vineyard regions. The aim of this paper was to assess the impact of various management practices on soil loss in vineyards. Effects of tillage, hoeing, rotavating and grass cover were evaluated in small vineyards located in southwestern Slovakia in the Vráble viticultural district. Erosion and deposition rates were estimated using the levelling method. This method is based on an evaluation of variability of the soil surface against vineyard poles measured between the year of pole insertion and the year of measurement. On the basis of the measured data, a WATEM/SEDEM distributed soil erosion model was calibrated, and the total soil loss from the vineyards under different management conditions was estimated. The model shows rather good performance in modelling soil erosion, but at the same time, it shows lower reliability in modelling soil deposition. Downslope tilled vineyards were the most eroded; the erosion in rotavated vineyards is somewhat reduced. The most protective tillage system is hoeing. Considerably lower soil loss was estimated with the use of vegetation cover between vine rows, which is in accordance with agro-environmental schemes supporting use of grass cover as an erosion prevention measure in vineyards. Copyright © 2012 John Wiley & Sons, Ltd.

This paper presents an annual multidisciplinary, non-spatial model which formalizes the relationships linking the dynamics of shrubs, herbs, soil, livestock and farmers' behaviour with possible exogenous drivers of degradation, such as weather and prices. The model does not represent a pasture–livestock system but a shrub–soil one and is applied to a rangeland in Lagadas County (Northern Greece). A sensitivity analysis of the model is also presented. It shows that livestock, in general, and factors increasing farmers' profits, in particular, are currently helping to combat shrub invasion in Lagadas while having low impacts on erosion rates. Copyright © 2012 John Wiley & Sons, Ltd.

Fast-growing tree species are widely used as pioneers for reforestation. These plantations strongly affect the ecosystem productivity and nutrient cycling, whereas their effect on the soil microbial community is still unclear. In a reforestation chronosequence in subtropical China consisting of Eucalyptus plantation with ages of 1, 2, 4 or 5 years, we examined the response of the soil microbial community and its function. The results showed that soil bulk density and dissolved organic carbon decreased significantly along the chronosequence. Soil pH was highest in the 5-year-old plantation. The amount of bacterial phospholipid fatty acids (PLFAs) and arbuscular mycorrhizal fungal PLFAs increased, but the ratio of fungal-to-bacterial PLFAs decreased with increasing forest age. The composition of the soil microbial community obviously changed after 5 years' development. Redundancy analysis showed that dissolved organic carbon was the major factor associated with the changes of soil microbial community composition. The short-rotation Eucalyptus plantation could affect the composition of soil microbial communities through changing soil available carbon when planted in subtropical region at the early developmental stage. We suggest that soil microbial community composition should be taken into consideration in the large-scale reforestation activities. Copyright © 2012 John Wiley & Sons, Ltd.

The proportional differences in soil organic carbon (SOC) and its fractions under different land uses are of significance for understanding the process of aggregation and soil carbon sequestration mechanisms. A study was conducted in a mixed vegetation cover watershed with forest, grass, cultivated and eroded lands in the degraded Shiwaliks of the lower Himalayas to assess land-use effects on profile SOC distribution and storage and to quantify the SOC fractions in water-stable aggregates (WSA) and bulk soils. The soil samples were collected from eroded, cultivated, forest and grassland soils for the analysis of SOC fractions and aggregate stability. The SOC in eroded surface soils was lower than in less disturbed grassland, cultivated and forest soils. The surface and subsurface soils of grassland and forest lands differentially contributed to the total profile carbon stock. The SOC stock in the 1.05-m soil profile was highest (83.5 Mg ha⁻¹) under forest and lowest (55.6 Mg ha⁻¹) in eroded lands. The SOC stock in the surface (0–15 cm) soil constituted 6.95, 27.6, 27 and 42.4 per cent of the total stock in the 1.05-m profile of eroded, cultivated, forest and grassland soils, respectively. The forest soils were found to sequester 22.4 Mg ha⁻¹ more SOC than the cultivated soils as measured in the 1.05-m soil profiles. The differences in aggregate SOC content among the land uses were more conspicuous in bigger water-stable macro-aggregates (WSA > 2 mm) than in water-stable micro-aggregates (WSA < 0.25 mm). The SOC in micro-aggregates (WSA < 0.25 mm) was found to be less vulnerable to changes in land use. The hot water soluble and labile carbon fractions were higher in the bulk soils of grasslands than in the individual aggregates, whereas particulate organic carbon was higher in the aggregates than in bulk soils. Copyright © 2012 John Wiley & Sons, Ltd.

Proper assessment of environmental quality or degradation requires knowledge of how terrestrial C pools respond to land use change. Forest plantations offer a considerable potential to sequester C in aboveground biomass. However, their impact on initial levels of soil organic carbon (SOC) varies from strong losses to gains, possibly affecting C balances in afforestation or reforestation initiatives. We compiled paired-plot studies on how SOC stocks under native vegetation change after planting fast-growth Eucalyptus species in Brazil, where these plantations are becoming increasingly important. SOC changes for the 0–20 and 0–40 cm depths varied between −25 and 42 Mg ha⁻¹, following a normal distribution centered near zero. After replacing native vegetation by Eucalyptus plantations, mean SOC changes were −1·5 and 0·3 Mg ha⁻¹ for the 0–20 and 0–40 cm depths, respectively. These are very low figures in comparison to C stocks usually sequestered in aboveground biomass and were statistically nonsignificant as demonstrated by a t-test at p < 0·05. Similar low, nonsignificant SOC changes were estimated after data were stratified into first or second rotation cycles, soil texture and biome (savanna, rainforest or grassland). Although strong SOC losses or gains effectively occurred in some cases, their underpinning causes could not be generally identified in the present work and must be ascribed in a case basis, considering the full set of environmental and management conditions. We conclude that Eucalyptus spp. plantations in average have no net effect on SOC stocks in Brazil. Copyright © 2012 John Wiley & Sons, Ltd.

The Mediterranean region covers about 854 million ha, but only 118 million (or 14 per cent) are suitable for agricultural production. In North Africa and the Middle East (MENA), agricultural land covers about 5 per cent; in Egypt and Algeria, it occupies less than 4 per cent and, in Libya, less than 2 per cent of the total national land area. Across the Mediterranean region land use divides between natural pastures/rangelands (ca. 15 per cent), forests and woodlands (ca. 8 per cent), with the ca. 63 per cent remaining desert sands, shallow, rocky, saline, sodic soils and areas effectively sealed by urbanisation. Land degradation is a severe problem in most Mediterranean countries. Estimates for the period 1961 to 2020 show that although the Mediterranean population is likely to more than double, ca. 8.3 million ha of agricultural land (7 per cent) may be lost as a result of continued urbanisation and land degradation. If these estimates are correct, agricultural land per capita would more than halve from ca. 0.48 ha (1961) to ca. 0.21 ha in 2020. Food security is likely to become increasingly problematic, especially in the MENA countries, which require a major reassessment of their agricultural development policy. Copyright © 2012 John Wiley & Sons, Ltd.

To study the magnitude of land degradation, desertification or resilience in Montenegro throughout the 20th and early-21st centuries, we rephotographed the landscapes recorded on 48 historical photographs dating back to between 1890 and 1985, and analysed in a semi-quantitative way the land use and cover changes that had occurred using an expert rating system (six correspondents). Time-series of hydrology and population density were analysed for the period since 1948 and were compared with the changes observed using repeat photography. Overall, vegetation cover has strongly increased, and barren areas occupy less space. The industrialisation that expanded in the 1950s led to strong urbanisation. Despite steadily increasing population (with the notable exception of the mountain region), the vegetation cover has increased markedly everywhere. This denser vegetation has led to higher infiltration of rainfall. Partitioning of water led, on one hand, to deep infiltration and better low flows and to increased evapo-transpiration at the boundary layer, leading to decreased total runoff coefficients. In the mountain region, runoff coefficients have increased, which may be related to earlier snowmelt. Overall, the findings of this study are in line with observations elsewhere in the former Socialist Federal Republic of Yugoslavia and suggest that, as a result of erosion control and significant vegetation regrowth, the changes observed over a century there has been land resilience and not degradation. Copyright © 2012 John Wiley & Sons, Ltd.

Soil organic carbon (SOC) and total nitrogen (TN) stocks can be affected by soil erosion and this is of great significance in relation to global environmental concern about environmental change. This study investigated the spatial patterns of ¹³⁷Cs, SOC and TN as well as their relationships for an agricultural catchment and presents a budget analysis of the redistributions of SOC and TN for the period 1954–2010. ¹³⁷Cs, SOC and TN inventories were found to be significantly correlated, and the application of the¹³⁷Cs technique proved to be useful for evaluating SOC and TN dynamics in the Luvic Phaeozem soil typical of the Chinese black soil region. Spatial patterns of soil, SOC and TN were greatly influenced by shelterbelts/windbreaks within the study catchment. Higher ¹³⁷Cs, SOC and TN stocks were generally found upwind of the shelterbelts and at the study catchment outlet, whereas lower stocks of ¹³⁷Cs, SOC and TN occurred behind the shelterbelts (i.e. in the lee). The total net losses of SOC and TN over the past 56 years were approximately 152 and 11 t respectively, with 47 and 38 per cent of the eroded SOC and TN in soils redeposited within the study catchment, respectively. Based on the relationships of soil, SOC and TN in the investigated catchment, erosion-induced SOC and TN losses per year are around 1·2 × 10⁶ and 0·1 × 10⁶ t for the typical black soil region of Northeast China. Copyright © 2012 John Wiley & Sons, Ltd.

This paper investigates the adoption of bench terraces by applying a three-stage analysis using data from 301 households in the highlands of Rwanda. Ongoing adoption of bench terraces is ‘unpacked’ to consider both adopters willing to retain and increase the intensity of using terraces already constructed and new adopters willing to develop new bench terraces. Results suggest that farmers' inability to maintain existing terraces may explain the reluctance to adopt new terraces. The same inability explains why some of the terraces constructed earlier are not well maintained and fully used by farmers in northern and southern Rwanda. Policy actions aimed at improving farmer's capacity to invest in complementary inputs will sustain future generations of soil and water conservation measures in Rwanda. Copyright © 2012 John Wiley & Sons, Ltd.

The combined effects of erosive rains, steep slopes and human land use have caused severe land degradation in the Ethiopian Highlands for several thousand years, but since the 1970s, however, land rehabilitation programmes have been established to try to reverse deterioration. In order to characterize and quantify the transformations in the north Ethiopian Highlands, a study was carried out over 8884 km² of the Tigray Highlands of northern Ethiopia. Using Landsat Multispectral Scanner and later Thematic Mapper imagery (1972, 1984/1986 and 2000), historical terrestrial photographs (1974–1975) and fieldwork (2008), we prepared land use and cover maps. For assessing the use of the historical terrestrial photographs, Landsat images from 1972 were classified using two different methods, namely conventional change detection (image differencing) and ground truthing (using the historical photographs of 1974–1975). Results show that the use of terrestrial photographs is promising, as the classification accuracy based on this method (Kappa coefficient 0·54) is better than the classification accuracy of the method based on image differencing (Kappa coefficient 0·46). Major land use and cover changes indicate the following: (1) a gradual but significant decline in bare ground (32 per cent in 1972 to 8 per cent in 2000); (2) a significant increase of bushland (25 to 43 per cent) and total forest area (including eucalypt plantations, 2·6 to 6·3 per cent); and (3) creation of numerous lakes and ponds. The dominant change trajectory (27 per cent of the study area) indicates a gradual or recent vegetation increase. These changes can be linked to the population growth and the introduction of land rehabilitation initiatives, complemented by growing awareness of land holders. Copyright © 2012 John Wiley & Sons, Ltd.

Deforestation in African dry forests is widespread and its drivers are complex and vary in space and time. In this paper, we assessed impacts of immigration on dry forests and options for improved management in a resettlement district in north-western Ethiopia. Key informants interviews, focus group discussions and household questionnaire survey were used to collect data. The results indicated that forests of the district are degrading in spatial coverage and quality. The most important drivers were land use change, excessive wood harvest, grazing pressure and forest fire following immigration. The continuous influx of people with different origins, cultures, religions and lengths of residence in the district underscores absence of social bonds for collective action to regulate access. This, coupled with weak formal regulatory system, market forces and policy incentives for farming, resulted in a near open access situation. Our findings confirm the negative relationships between migration and environment not necessarily because of the mere population number added through immigration but because of lack of regulatory frameworks (formal or informal) and poor social capital. Enforcing existing policy of farm size and putting institutional framework on the ground to regulate rate of immigration, extraction of forest products and to encourage tree planting to meet wood demand are suggested measures. We conclude that Government programmes that opt for resettlement as a measure for poverty alleviation must also have mitigating measures to reducing negative impacts on the natural resource base. Thus, the trade-off between environment and development must be carefully managed. Copyright © 2012 John Wiley & Sons, Ltd.

The aim of this study was to measure the in situ soil CO₂ flux from grassland, afforested land and reclaimed coalmine overburden dumps by using the automated soil CO₂ flux system (LICOR-8100® infrared gas analyzer, LICOR Inc., Lincoln, NE). The highest soil CO₂ flux was observed in natural grassland (11·16 µmol CO₂ m⁻²s⁻¹), whereas the flux was reduced by 38 and 59 per cent in mowed site and at 15-cm depth, respectively. The flux from afforested area was found 5·70 µmol CO₂ m⁻²s⁻¹, which is 50 per cent lower than natural grassland. In the reclaimed coalmine overburden dumps, the average flux under tree plantation was found to be lowest in winter and summer (0·89–1·12 µmol CO₂ m⁻²s⁻¹) and highest during late monsoon (3–3·5 µmol CO₂ m⁻²s⁻¹). During late monsoon, the moisture content was found to be higher (6–7·5 per cent), which leads to higher microbial activity and decomposition. In the same area under grass cover, soil CO₂ flux was found to be higher (8·94 µmol CO₂ m⁻²s⁻¹) compared with tree plantation areas because of higher root respiration and microbial activity. The rate of CO₂ flux was found to be determined predominantly by soil moisture and soil temperature. Our study indicates that the forest ecosystem plays a crucial role in combating global warming than grassland; however, to reduce CO₂ flux from grassland, mowing is necessary. Copyright © 2012 John Wiley & Sons, Ltd.

To understand how shrub cover affects the spatiotemporal patterns of the soil seed bank and to assess the role of vegetation in the restoration of desertified land in a semi-arid region of China, we investigated the species composition and seed density of the soil seed bank under and outside the canopies over two seasons for an age sequence of Caragana microphylla shrubs in the Horqin Sandy Land region, Inner Mongolia. The results showed that a total of 24 plant species seeds were present in the soil seed bank, of which 20 were annuals or biennials. The seed densities in the soil seed bank were in the range of 830 – 13882·5 seeds m⁻² at 10 cm depth. Species richness in the soil seed bank did not increase as the shrubs aged, whereas the seed densities increased significantly. Five annual species: Setaria viridis, Eragrostis pilosa, Chenopodium acuminatum, Chenopodium glaucum and Corispermum acuminatum, contributed above 90 per cent of the seeds to the soil seed bank. On the basis of seed characteristics and seed reduction amount during the growing season, we concluded that it represents a mixture of persistent and transient seeds in different proportions. More seeds accumulated under the canopies than outside the mature shrub cover, but no significant difference was found the younger cover. These results suggest that shrub size and age had an important role in augmenting seed abundance of the soil seed bank but not the species richness. We confirmed the important effects of shrub cover on seed accumulation and vegetation recovery, especially the value of more mature age vegetation for countering land degradation. Copyright © 2012 John Wiley & Sons, Ltd.

Large areas in the Upper Tana river catchment, Kenya, have been over-exploited, resulting in soil erosion, nutrient depletion and loss of soil organic matter (SOM). This study focuses on sections of the catchment earmarked as being most promising for implementing Green Water Credits, an incentive mechanism to help farmers invest in land and soil management activities that affect all fresh water resources at source. Such management practices can also help restore SOM levels towards their natural level. Opportunities to increase soil organic carbon (SOC) stocks, for two broadly defined land use types (croplands and plantation crops, with moderate input levels), are calculated using a simple empirical model, using three scenarios for the proportion of suitable land that may be treated with these practices (low = 40 per cent, medium = 60 per cent, high = 80 per cent). For the medium scenario, corresponding to implementation on ~348 000 ha in the basin, the eco-technologically possible SOC gains are estimated at 4·8 to 9·3 × 10⁶ tonnes (Mg) CO₂ over the next 20 years. Assuming a conservative price of US$10 per tonne CO₂-equivalent on the carbon offset market, this would correspond to ~US$48–93 million over a 20-year period of sustained green water management. This would imply a projected (potential) payment of some US$7–13 ha⁻¹ to farmers annually; this sum would be in addition to incentives that are being put in place for implementing green water management practices and also in addition to the benefits that farmers would realize from the impact on production of these practices themselves. Copyright © 2012 John Wiley & Sons, Ltd.

Emergence of policies dealing with concern over soil degradation and anthropogenic impacts to soil is likely to increase the requirement for assessment of soil quality and identification of soils at risk from degradation. An example is the proposed EU Soil Framework Directive, which features the identification of areas requiring protection from soil degradation. There have been some serious objections to such requirements on the grounds of resource and capital demands. To help to address these concerns, this work proposes a strategic set of indicators based on measured soil quality indicators. These can be used in screening locations to assess the likelihood of degradation and indicate areas for further detailed assessment. This will allow further emphasis to be placed on a smaller number of locations, which could lead to cost and resource efficiencies. Indicators have been used in the past in assessment of soil quality; they are parameters which can be measured and correspond to assessment criteria to measure and help monitor the status and changes. The study reviews the current state of soil quality assessment including methods and indicators that are used to collect data and approaches used to assess data to determine areas subject to soil degradation. Methods and practicalities for data collection and screening are discussed, including the need for further pilot testing and protocol development. Use of public data collection could allow more resource efficient protection of soils, in addition to benefits of public engagement, and raising awareness of the importance of soils and soil biodiversity. Copyright © 2012 John Wiley & Sons, Ltd.

The effects of conceptual land cover change scenarios on the generation of storm runoffs were evaluated in the Nyando Basin. The spatial scenarios represented alternatives that vary between full deforestation and reforestation. Synthetic storm events of depths 40, 60 and 80 mm were formulated according to the rainfall patterns and assumed to have durations corresponding to the runoff times of concentration. The Natural Resource Conservation Service–Curve Number model was used to generate runoff volumes within the sub-catchments, which were subsequently routed downstream to obtain effects in the whole basin. The simulated land cover change impacts were evaluated relative to values obtained from the actual land cover state of the basin in the year 2000. From the results, an agricultural land cover scenario constituting of about 86 per cent of agriculture indicated increased runoff volumes in the entire basin by about 12 per cent. An agricultural-forested land cover scenario with 40 and 51 per cent of forest and agriculture respectively revealed reduced runoff volumes by about 12 per cent. Alternatively, a scenario depicting a largely forested land cover state with about 78 per cent of forests reduced the runoff volumes by about 25 per cent according to the model estimates. Runoff volumes in the basin were also likely to reduce by about 15 per cent if the appropriate land cover scenario for the respective sub-catchments were to be assumed for runoff management purposes. Considering the prevalent data uncertainty, the study effectively highlights the potential hydrological vulnerability of the basin. The results obtained can form a basis for appropriate catchment management of the area. Copyright © 2012 John Wiley & Sons, Ltd.

The Qinghai–Tibet Railway is frequently damaged by windblown sand, and this hinders railway operation. To better understand the characteristics of windblown sand near the railway, wind tunnel experiments were conducted for the Tuotuo River Section, a typical stretch suffering from windblown sand damage. According to climate data, the windy period combines with an arid seasonal climate to increase the risk of blowing sand in this area. Wind tunnel simulation results showed how the airflow interacted with the railway embankment to create sand deposition as well as aeolian erosion. Sand transport rates behind the railbed fitted a Gaussian function well. The results can be used to guide the design of sand-control structures both in the study area and in other areas that experience threats from windblown sand. Copyright © 2012 John Wiley & Sons, Ltd.

Rangeland degradation not only affects animal production but also threatens ecological quality throughout the world. In this study, a functional classification index (FCI_i) for rangelands was designed to determine the management pattern of different sub-rangeland vegetation types this index combines the productive value (GP_i), ecological services value (GE_i), ecological sensitivity (ESI_i) and seasonal grazing importance (SGI_i) of each rangeland subtype and can be used for coordinating the relationships between animal production and ecological conservation. On the basis of the FCI_i of each rangeland subtype, the northern Tibetan rangelands were classified into a conservation sector, mixed sector and production sector. The conservation sector covering 0·47 million ha accounted for 13·9 per cent of the total rangeland area, and this had significant ecological and social values but was of low productivity. In the conservation sector, grazing should be forbidden so that degraded rangelands can be restored. The mixed sector covered 2·16 million ha, 63·9 per cent of the total rangeland area, and offered multiple benefits, in which increasing the number of head of livestock for sale would improve the income of local herders. A 0·75 million ha production sector accounted for 22·2 per cent of the total rangeland area and was applied to maximise economic benefits by establishing modern pasture systems to increase the income of local herders and thus partly offset the losses arising from the conservation sector. This study suggested that the area of the three functional sectors should be adjusted at appropriate times according to the changes in productivity and ecological values of each rangeland subtype. Copyright © 2012 John Wiley & Sons, Ltd.

In the Far West Texas region in the USA, long-term irrigation of fine-textured valley soils with saline Rio Grande River water has led to soil salinity and sodicity problems. Soil salinity [measured by saturated paste electrical conductivity (EC_e)] and sodicity [measured by sodium adsorption ratio (SAR)] in the irrigated areas have resulted in poor growing conditions, reduced crop yields, and declining farm profitability. Understanding the spatial distribution of EC_e and SAR within the affected areas is necessary for developing management practices. Conventional methods of assessing EC_e and SAR distribution at a high spatial resolution are expensive and time consuming. This study evaluated the accuracy of electromagnetic induction (EMI), which measures apparent electrical conductivity (EC_a), to delineate EC_e and SAR distribution in two cotton fields located in the Hudspeth and El Paso Counties of Texas, USA. Calibration equations for converting EC_a into EC_e and SAR were derived using the multiple linear regression (MLR) model included in the EC_e Sampling Assessment and Prediction program package developed by the US Salinity Laboratory. Correlations between EC_a and soil variables (clay content, EC_e, SAR) were highly significant (p ≤ 0·05). This was further confirmed by significant (p ≤ 0·05) MLRs used for estimating EC_e and SAR. The EC_e and SAR determined by EC_a closely matched the measured EC_e and SAR values of the study site soils, which ranged from 0·47 to 9·87 dS m⁻¹ and 2·27 to 27·4 mmol^1/2 L^−1/2, respectively. High R² values between estimated and measured soil EC_e and SAR values validated the MLR model results. Results of this study indicated that the EMI method can be used for rapid and accurate delineation of salinity and sodicity distribution within the affected area. Copyright © 2012 John Wiley & Sons, Ltd.

The severity of soil erosion is considered to vary according to the structure of the bench terrace and the ground cover conditions. Erosion losses were investigated in a field experiment based on 20 m × 5 m erosion plots on a 21 per cent slope in Southern China. Five plots were established for the present study. Rainfall, runoff and sediment yield from plots were recorded for 5 years (2001–2005) and which five different types of terraces on sloping red soil were compared. The results show that the planting of grass on the riser is the most important factor affecting runoff and sediment yield, the next most important factor was the construction of a bund built on the edge of the terrace. Although the terrace bed slope (slope < 5 degrees) does not significantly affect the runoff, it does benefit the soil. A terrace combined with vegetation measures is effective in controlling runoff and soil erosion. Among various terraces, the level terrace (i.e. grass planted on the riser and bunds built on the edge of a bench terrace) is apparently the most beneficial for soil conservation purposes, indicating that this type is an excellent choice for conserving soil and water resources in sloping red soil in Southeastern China. Copyright © 2012 John Wiley & Sons, Ltd.

Impacts of land use and climate change on runoff were investigated by studying the runoff in the Yarlung Zangbo River basin, China. Trends in precipitation, mean air temperature, and runoff were analysed by non-parametric Mann-Kendall tests. Land-use changes were examined with land-use transition matrix and geographic information system tools. Land-use and climate changes showed several characteristics, including increased reforestation, decreased grassland, retreat of glaciers and increased desertification. Human activity caused great impact, especially within densely populated regions and cities. Reforestation and degradation of grasslands were more frequent than deforestation and cultivation of grasslands. Annual mean air temperature, precipitation and runoff showed increasing trends between 1974 and 2000. The impacts of land use and climate change on runoff had different effects depending on region and season. In the season of freezing, climate change clearly affected runoff within regions that experienced precipitation. Altered evapotranspiration accounted for about 80 per cent of runoff changes, whereas land-use changes appear to have had greatest impact on runoff changes within regions that have inconsistent relationships between runoff and climate change. It was demonstrated that afforestation leads to increased runoff in dry seasons. It was estimated that glacier snow melt has caused annual runoff to increase at least 6·0 mm/10yr, 2·1 mm/10yr and 1·7 mm/10yr in Regions 1, 3 and 4, respectively, whereas evapotranspiration caused annual runoff to decrease at least 7·4 mm/10yr in Region 2. Copyright © 2012 John Wiley & Sons, Ltd.

Soil organic carbon (SOC) pools are important for maintaining soil productivity and reducing the net CO₂ loading of the atmosphere. An 18-year old long-term field experiment involving pearl millet-cluster bean-castor sequence was conducted on an Entisol in western India to examine the effects of chemical fertilizers and manuring on carbon pools in relation to crop productivity and C sequestration. The data showed that even the addition of 33.5 Mg ha⁻¹ C inputs through crop residues as well as farm yard manure could not compensate the SOC depletion by oxidation and resulted in the net loss of 4.4 Mg C ha⁻¹ in 18 years. The loss of SOC stock in the control was 12 Mg C ha⁻¹. Conjunctive use of chemical fertilizers along with farm yard manure produced higher agronomic yields and reduced the rate of SOC depletion. The higher average seed yields of pearl millet (809 kg ha⁻¹), cluster bean (576), and castor (827) over six cropping seasons were obtained through integrated use of fertilizers and manure. For every Mg increase in profile SOC stock, there was an overall increase of 0.46 Mg of crop yield, comprising increase in individual yield of pearl millet (0.17 Mg ha⁻¹ y⁻¹ Mg⁻¹ SOC), cluster bean (0.14) and castor (0.15). The magnitude of SOC build up was proportional to the C inputs. Carbon pools were significantly correlated with SOC, which increased with application of organic amendments. Threshold C input of 3.3 Mg C ha⁻¹ y⁻¹ was needed to maintain the SOC stock even at the low antecedent level. Copyright © 2011 John Wiley & Sons, Ltd.

Knowledge of the effects of land use on soil moisture variations is necessary to improve land and agricultural water management in the semi-arid Chinese Loess Plateau. However, previous studies are insufficient to guide management practice in this area and improvement is needed to help with the development of the ‘Grain for Green’ programme. As part of the ‘Grain for Green’ programme, we examined the effects of five land uses (fallow, grassland, cropland, 3-year and 8-year jujube orchards) on soil water variations in a small catchment on the Loess Plateau. Soil moisture at 0–160 cm depth was monitored approximately weekly at 47 sites from 17 August to 19 October 2009 and from 4 April to 27 September 2010 using a portable time domain reflectometer. Results indicated that mean soil water profiles in different land uses varied with time, land use induced spatial variations of soil water but exerted negligible influence on soil water temporal patterns, and soil water content was of the greatest spatial variability with moderate means (approximately 20 per cent). Furthermore, the relationship between standard deviation and mean water content was dependent on soil depth, although it was negligibly affected by land use. Profile soil water for five land uses was different in various seasons, precipitation infiltration depth exhibited a positive correlation with precipitation, and the whole profile soil moisture (0–160 cm) was complemented following a 93·5-mm rainfall event. The findings presented here provide helpful information for land and agricultural water management in this area. Copyright © 2011 John Wiley & Sons, Ltd.

Over the last few decades, road construction has increased dramatically, and new surfaces have appeared in most landscapes. Standard roadside reclamation practices often fail, because vegetation establishment appears to be limited by microsite availability. We considered soil properties as a key factor driving vegetation establishment on roadslopes over time. We address the following questions: (i) Are soil features conditioned by type of roadslope, position thereupon or applied hydroseeding? (ii) Is there any evidence of soil development at the roadside four years after road construction? (iii) Do mutual interactions exist between soil features and vegetation cover? We designed an experimental set-up on a highway in Central Spain (Madrid). We selected 15 roadslopes (nine roadcuts and six embankments) with three hydroseeding treatments (commercial, alternative and untreated). Four years after the road construction, we considered three roadslope positions (top, middle and bottom) to take into account the geomorphological gradient. We monitored soil features and vegetation cover over 4 years after the road construction. Soil chemical differences were found between roadslope types, mainly resulted from topsoil spreading on embankments and the weathering of the newly exposed materials on roadcuts. Applied amendments do not affect soil fertility or vegetation cover. In the course of time, vegetation establishment and geomorphological gradients operate differentially on roadcuts and embankments. Accordingly, cycling back of organic compounds or geomorphological processes differs between roadslopes types. Restoration efforts should be directed to guarantee key ecological processes and support soil formation. Copyright © 2011 John Wiley & Sons, Ltd.

Knowledge of clay dispersion behaviour [which is highly influenced by ion concentration in the aqueous phase and by related surface charge (SC) of colloids] is important for rating soil erosion risk (by water). It can also be useful for improving soil management systems. Clay fractions separated from samples of the A-horizon of a Vertisol, Ultisol and Oxisol were collected, representing typical soils of North Cameroon. These soils were very different in physicochemical and mineral parameters. The effect of pH and the multivalent ions Ca²⁺, SO₄²⁻ and PO₄³⁻ on SC and dispersion characteristics were determined. The water dispersible clay was found to be higher in the Vertisol and Ultisol than in the Oxisol, indicating that the <2 µm fractions from the Vertisol and Ultisol are more dispersible than that from the Oxisol. The clay dispersion ratio together with the dispersion ratio were found to be in good agreement with water dispersible clay and are negatively correlated with the amount of organic matter and dithionite citrate bicarbonate soluble Fe and Al. Generally, SC of the <2 µm fraction was found to be negative when the pH was in the region of 3 to 9; thus the absolute value is highly pH-dependent. At pH 6 and 8, CaCl₂, Na₂SO₄ and Na₂HPO₄ additions had antagonistic effects on SC: Ca²⁺ increased SC, whereas SO₄²⁻ and PO₄³⁻decreased SC indicating the adsorption of positively as well as negatively charged multivalent ions by soil colloids. Along with the increase of SC, there was a fall in repulsive forces and formation of Ca-bridges, the addition of Ca²⁺ induced flocculation more rapidly than SO₄²⁻ and PO₄³⁻ amendments. Copyright © 2011 John Wiley & Sons, Ltd.

Although the human domestication of forest and tree resources is often considered to result in resource degradation, it may also lead to improved resource potentials. This paper assesses the nature and dynamics of gum and resin focused woodland exploitation and management systems in Ethiopia in the context of degradation and domestication processes. In three sites with commercial gum resin producing woodlands and production history, we studied variation in (i) woodland management and gum resin production systems and (ii) socio-economic and biophysical factors that condition the management and production systems. On the basis of their organizational features, we formulated nine production models and related them to different phases of domestication and different degrees of ecosystem degradation. The production systems gradually evolved from the extraction of wild trees to production in an adapted forest system. However, domesticated woodlands with an adapted forest structure and composition and increased provisioning services are still little developed despite decades of production history. Many of these woodlands are undergoing serious degradation because of low quality management practices. This is mainly attributable to existing land use practices and the social arrangements for the production of and trade in the gums and resins. The findings illustrate that domestication involves not only a change in ecological and production systems but also the development of social arrangements for production and trade. We conclude that the status of domestication in a social sense determines whether forests and/or specific forest resources are degraded or aggraded in the sense of resource enrichment. Copyright © 2011 John Wiley & Sons, Ltd.

The objectives of this study, conducted in Bou-Hedma National Park, were to quantify the effects of the dominant legume Acacia tortilis subsp. raddiana on soil properties. Three sites with differing soil texture were studied; the first with a gravelly-sand texture, the second with a sandy-loam texture and the third with a loam texture. At each study site, two subhabitats were distinguished, under Acacia canopies (canopied soil) and open areas (uncanopied soil). Soil organic carbon, microbial biomass and microbial coefficient were found to be significantly greater in canopied soil, compared with uncanopied soil. The lower metabolic quotient under this legume indicated a higher carbon use efficiency of microorganisms in soil. The enzyme activities (dehydrogenase, phosphatase and β-glucosidase) expressing soil microbial activity were significantly higher under Acacia canopies. Therefore, A. raddiana planting can be considered an effective and applicable measure to restore vegetation and control desertification in arid regions.

On account of the variability of soil texture in the park, three sites were studied: gravelly-sand, sandy-loam and loam soils. The highest microbial density and activity were registrated in sandy-loam soil. Microbial biomass and activity increased gradually and significantly to a maximum at 20–30 cm and subsequently decreased at 30–50 cm. The results allow us to conclude that soil texture and soil depth can play an important role in the extent of soil properties. Copyright © 2011 John Wiley & Sons, Ltd.

Land degradation is a gradual, negative environmental process that is accelerated by human activities. Its gradual nature allows degradation to proceed unnoticed, thus reducing the likelihood of appropriate and timely control action. Presently, there are few practical frameworks to help countries design national strategies and policies for its control. The study presented here developed a framework for the national assessment of land degradation. This framework is envisaged to support governments in formulating policies on land degradation. It uses time-series remote sensing data to identify the rate and extent of land degradation, local experts to identify prevalent degradation types and drivers of the degradation and field observations to validate the overall assessment. Its simplicity, use of freely downloadable input data and self-triangulation of the assessment methods make it suitable for rapid assessment of land degradation on a national scale. It was tested in Somalia, where it exhibited accuracy greater than 60 per cent when assessing land degradation. This framework is relevant for designing national strategies and policies that address land degradation and provides an opportunity for accurate identification of areas to target with comprehensive local assessment. Testing of the framework in Somalia showed that about one-third of the country was degraded because of loss of vegetation cover, topsoil loss and to the decline of soil moisture. Overgrazing, excessive tree cutting and poor agronomic practices in agricultural areas were identified as the primary drivers of the country's land degradation. These drivers are encouraged by the prevailing communal land tenure practices, poor governance and civil war. Copyright © 2011 John Wiley & Sons, Ltd.

The primary objective of this study was to analyze soil degradation and altered flood risks as a consequence of deforestation. The results showed that the use of fuelwood and competition for agriculture land are the main causes of deforestation, which leads to increased soil erosion and floods. The consequences and the societal risks from floods are quantified. This study indicates that the numbers of fatalities and mortality per river flood event are lower compared with those caused by flash floods. Copyright © 2011 John Wiley & Sons, Ltd.

The effects of compost application on soil carbon sequestration potential and carbon budget of a tropical sandy soil was studied. Greenhouse gas emissions from soil surface and agricultural inputs (fertiliser and fossil fuel uses) were evaluated. The origin of soil organic carbon was identified by using stable carbon isotope. The CO₂, CH₄ and N₂O emissions from soil were estimated in hill evergreen forest (NF) plot as reference, and in the corn cultivation plots with compost application rate at 30 Mg ha⁻¹ y⁻¹ (LC), and at 50 Mg ha⁻¹ y⁻¹ (HC). The total C emissions from soil surface were 8·54, 10·14 and 9·86 Mg C ha⁻¹ y⁻¹ for NF, HC and LC soils, respectively. Total N₂O emissions from HC and LC plots (2·56 and 3·47 kg N₂O ha⁻¹ y⁻¹) were significantly higher than from the NF plot (1·47 kg N₂O ha⁻¹ y⁻¹). Total CO₂ emissions from fuel uses of fertiliser, irrigation and machinery were about 10 per cent of total CO₂ emissions. For soil carbon storage, since 1983, it has been increased significantly (12 Mg ha⁻¹) under the application of 50 Mg ha⁻¹ y⁻¹ of compost but not with 30 Mg ha⁻¹ y⁻¹. The net C budget when balancing out carbon inputs and outputs from soil for NF, HC and LC soils were +3·24, −2·50 and +2·07 Mg C ha⁻¹ y⁻¹, respectively. Stable isotope of carbon (δ¹³C value) indicates that most of the increased soil carbon is derived from the compost inputs and/or corn biomass. Copyright © 2011 John Wiley & Sons, Ltd.

The aim of this work is to assess the effect of planting patterns on the spatial distribution of total copper and other Cu fractions in vineyard soils. Both classical and geostatistical tools were used for the study. The soil of the plot had a loam texture and was strongly acid. The mean total Cu concentration (Cu_T) was 368 mg kg⁻¹. The mean value of potential available fractions was 188 mg kg⁻¹ for Cu_EDTA and 122 mg kg⁻¹ for Cu_DPTA, whereas the mean exchangeable Cu (Cu_EX) was 5·2 mg kg⁻¹. All Cu measurements exhibited a wide variation. These values are very high compared with those found in non-polluted soils, and they can affect the soil, plants and microorganisms. The best correlation for Cu_EX was with soil pH, whereas for Cu_EDTA, Cu_DPTA, and Cu_T, the best correlation was with soil organic carbon. Directional semivariograms were fitted with a spherical model (parallel to plant rows) and a periodic model (perpendicular) showing a dependence on orientation and distance. All Cu measurements were higher along plant rows than among them, finding a periodic pattern in the variance for the normal direction from plant rows. However, in site-specific management, it is crucial not only to describe the pattern of variation but also to estimate the Cu content in the soil. Copper concentration maps were estimated by kriging interpolation. These maps show a higher Cu accumulation along the cultivated rows than the uncultivated rows. Copyright © 2011 John Wiley & Sons, Ltd.

Northern peatlands have accumulated a carbon pool of approximately 455 to 547 GtC, and they can make significant contributions to national carbon fluxes. Ireland is an example of a northern latitude country where peatlands are of significance for carbon management. Peatlands in Ireland cover ~20 per cent of the Country and contain nearly two-thirds of the national soil organic carbon stock. Peatland disturbance was defined, and a framework for the classification of disturbance was developed. The classification process is subjective. To account for this, a survey was conducted among several peatland experts to determine if their opinions differed from the authors'. There was no significant difference between the authors' and the peatland experts' or among each of the peatland expert's opinions. A preliminary classification survey was carried out at 172 points (photos taken at 115). The results for the preliminary study were compared with those of the survey. The expert's average scores for less disturbed and more disturbed areas favourably compared with the results from the disturbance framework. This is a robust, quick and efficient method for assessing peatland disturbance and may be applied to peatlands throughout the globe. Copyright © 2011 John Wiley & Sons, Ltd.

Field studies were carried out near Lake Muhazi, Rwanda, to investigate the pollutants present and salinity of soils and the physicochemical content of aeolian dust. The data on aeolian dust and saline sediments showed that soil formation and salinization may be related to aeolian processes. The ecological status of the region a major cause of aeolian material in the Lake. The results revealed that dust originating from the dried bottom of the Lake and riversides contribute to the formation of East African dust storms and adversely affects the climate of the region. Apart from copper and zinc that were identified as heavy metals that polluted the Lake, petroleum products, Fe and Mn were also the main pollutants. Chemical properties of the soils are related to sediment composition of aeolian material, some elements like Zn, Fe, Cd and Cu. Copyright © 2011 John Wiley & Sons, Ltd.

This research investigated empirically the qualities of improved soil management practices (ISMPs) most likely to lead to land user adoption. Land users' perceptions of soil-related constraints were investigated in two hillside districts of eastern Uganda. The research looked at land user rationale for adopting and adapting specific ISMPs at the end of a two-year period of increased advice and support. Land user engagement with soil management improved markedly after this period of support and multifunctionality, that is, provision of a number of different products or benefits, was seen to be a common characteristic of those ISMPs taken up by land users. It is argued that in the search for ‘best-bet’ ISMPs, multifunctionality may be a particularly relevant and easily measurable indicator of likely adoption of a practice by land users. The research also demonstrates the value of supporting land users in their efforts to adapt ISMPs to fit with their own circumstances. Copyright © 2011 John Wiley & Sons, Ltd.

In the northern highlands of Ethiopia, establishment of exclosures to restore degraded communal grazing lands has been practiced for the past three decades. However, empirical data on the effectiveness of exclosures in restoring degraded soils are lacking. We investigated the influence of exclosure age on degree of restoration of degraded soil and identified easily measurable biophysical and management-related factors that can be used to predict soil nutrient restoration. We selected replicated (n = 3) 5-, 10-, 15-, and 20-year-old exclosures and paired each exclosure with samples from adjacent communal grazing lands. All exclosures showed higher total soil nitrogen (N), available phosphorus (P), and cation exchange capacity than the communal grazing lands. The differences varied between 2·4 (±0·61) and 6·9 (±1·85) Mg ha⁻¹ for the total N stock and from 17 (±3) to 39 (±7) kg ha⁻¹ for the available P stock. The differences in N and P increased with exclosure age. In exclosures, much of the variability in soil N (R² = 0·64) and P (R² = 0·71) stocks were explained by a combination of annual average precipitation, woody biomass, and exclosure age. Precipitation and vegetation canopy cover also explained much of the variability in soil N (R² = 0·74) and P (R² = 0·52) stocks in communal grazing lands. Converting degraded communal grazing lands into exclosures is a viable option to restore degraded soils. Our results also confirm that the possibility to predict the changes in soil nutrient content after exclosure establishment using regression models is based on field measurements. Copyright © 2011 John Wiley & Sons, Ltd.

Soil salinity is a global issue and one of the major causes of land degradation. The large scale monitoring of salt-affected areas is therefore very important to shed light on necessary rehabilitation measures and to avoid further land degradation. We address the productivity limitation of salt-affected soils across the European continent by the usage of soil maps and high temporal resolution time series of satellite images derived from the SPOT vegetation sensor. Using the yearly dynamism of the vegetation signal derived from the Normalised Difference Vegetation Index, we decomposed the spectral curve into its base fraction and seasonal dynamism fractions next to an index approximating gross primary productivity. We observe gross primary productivity, base fraction and seasonal dynamism productivity differences of saline, sodic and not salt-affected soils under croplands and grasslands in four major climatic zones of the European continent. Analysis of variance models and post hoc tests of mean productivity values indicate significant productivity differences between the observed salt-affected and salt free areas, between management levels of soils as well as between the saline and sodic character of the land. The analysis gives insight into the limiting effect of climate in relation to the productivity of salt-affected soils. The proposed indicators are applicable on the global level, are objective and readily repeatable with yearly updates, thus, might contribute to the global operational monitoring and assessment of degraded lands. Copyright © 2011 John Wiley & Sons, Ltd.

After decades of drought in the Sahel, several studies have reported a ‘(re)greening’ of the area. However, most of these studies were based on large scale climatological or remotely sensed observations, with little or no ground truthing. The aim of this study was to assess the local perceptions of the distribution of socio-economically important tree species in the Sub-Sahel of Burkina Faso. Semi-structured interviews were performed with 87 groups of informants from 20 villages belonging to three ethnic groups (Mossi, Fulani and Samo). Univariate and multivariate statistics were used to compare perceptions between the targeted ethnic groups. According to the locals, more than 80 per cent of the 90 listed species were declining, with over 40 per cent identified as threatened, including numerous plants of great economic value. Increasing species were mostly drought-tolerant plants such as Balanites aegyptiaca. A few species were listed as locally extinct. Gender and age did not significantly affect local knowledge, whereas ethnicity did. The major causes of species decline were identified to be drought, deforestation and bushfires. In all ethnic groups, informants observed a southward shift in species distribution. Local perceptions suggest a general decline in woody vegetation. Thus, the alleged (re)greening in the Sahel might not have reversed the degradation of woody species in the area. Data derived from local ecological knowledge were consistent with that of many ecological studies, suggesting the reliability of people's knowledge for obtaining ecological data. Information from this study can be used as baseline for conservation of species identified as threatened. Copyright © 2011 John Wiley & Sons, Ltd.

It is increasingly recognised that tackling land degradation through more sustainable land management depends on incorporating multiple perspectives by using a variety of methods at multiple scales, including the perspectives of those who manage and/or use the land. This paper reports experience implementing a previously proposed methodological framework that is designed to facilitate knowledge sharing between researchers and stakeholders about land degradation severity and extent, and sustainable land management options. Empirical findings are presented from the Botswana site of the EU-funded Desertification Mitigation and Remediation of Land project. The paper reflects upon the challenges and benefits of the proposed framework and identifies a number of benefits, notably related to insights arising from the integration of local and scientific knowledge, and the ownership of the sustainable land management strategies that emerged from the process. However, implementing the framework was not without challenges, and levels of poverty and formal education may limit the implementation of the framework in some developing world contexts. Copyright © 2011 John Wiley & Sons, Ltd.

Vegetation in many arid and semi-arid shrublands frequently occurs in patches with high plant cover (shrub patches) interspersed in a low-cover herbaceous matrix (inter-shrub areas). We hypothesized that (a) livestock grazing is an important determinant of such spatial patterns of vegetation, and (b) redistribution of soil resources associated with shrub patches helps in the recovery of vegetation in inter-shrub areas. To test these hypotheses, we (a) used line transects to compare spatial variations in vegetation, soil microtopography, and soil physicochemical properties in grazed areas and areas protected from grazing since 1970, (b) added sediment and seeds to inter-shrub areas, and (c) measured resource redistribution after a wildfire. Results were consistent with the hypotheses. They indicated greater spatial heterogeneity in vegetation, soil microtopography and soil physicochemical properties in grazed areas than in protected areas, and that addition of sediment and seeds or redistribution of soil resources from shrub patches after a wildfire enhanced re-establishment of vegetation in degraded inter-shrub areas. As a synthesis, a conceptual model of degradation and recovery processes in semi-arid shrublands of Northern Patagonia is presented. Copyright © 2011 John Wiley & Sons, Ltd.

To date, the mechanical control of drifting sand is the main method used for the protection of the Qinghai-Tibet Railway from damage. The thermal effect of sandy sediments which are held in place on the underlying permafrost is a key area of interest and the focus of this paper. A ground temperature investigation of the permafrost along the railway route was undertaken and results were related to the different mechanical control measures used to control moving sand which had resulted in varying sandy sediment thicknesses. The studies were conducted in the Hongliang River area of the Qinghai-Tibet Plateau from June 2010 to September 2010 using thermistor sensors. The results showed that the permafrost ground temperature and its daily variation, as well as the thawing depth of the active layer, decreased after the setting-up of sand movement controls which had resulted in the accumulation of thick sandy sediments within the outside fringe of sand-control engineering, or a covering of thin sandy sediments within the inside trackside (fringe) of sand-control engineering. Below the thick sandy sediment cover accumulated by sand-blocking fences, the average maximum temperature decreased. Average temperature decreased and the average depth of seasonal thawing (average thinning) were 3·38°C, 0·54°C and 0·48 m, respectively. Below the thin sand sediment cover accumulated by the checkerboard sand barriers, the values for the same parameters were 1·02°C, 0·21°C and 0·5 m, respectively. This study found that the mechanical control of sand does not only protect the railway from obstruction, but also facilitates permafrost stability, which in turn can help promote safety in railway operations. Copyright © 2011 John Wiley & Sons, Ltd.

Management practices to minimise soil erosion can be effectively carried out if the magnitude and the spatial distribution of soil erosion risk areas are known. Prioritisation of soil erosion risk areas is a challenging task, especially in the developing countries because of non-availability of relevant data and analytical tools for such an assessment. As a result, it becomes difficult to establish appropriate soil conservation measures on the risk-prone areas to reduce soil loss and ensure development of a sustainable management of soil resources. Such a database can be better generated and analysed in a geographical information system (GIS) environment to delineate and prioritise the soil erosion risk areas at state or regional level. Therefore, a methodology was developed to assess the soil erosion risks in eastern Himalayan region by integrating spatial data on prevailing erosion rates and soil loss tolerance limits in GIS environment. By comparing the potential erosion rates with permissible rates, we observed that about 58·94 per cent of total geographical area (TGA) of the region requires different degrees of erosion management and 28·38 per cent of TGA falls under no treatment category because of higher values of permissible erosion limits. It can be successfully applied to assess and prioritise soil erosion risks in any region or country and identify best management practices to bring the erosion losses within the permissible limits. Copyright © 2011 John Wiley & Sons, Ltd.

Mycorrhizal fungi form symbiotic associations with the roots of most vascular plant species and can improve both plant growth and soil structure. Therefore, they are expected to play an important role in reducing soil erosion by wind. However, direct evidence for this is lacking, because it is hardly possible to separate the mycorrhizal effect from all other factors that influence wind erosion in natural environments. Here, we present laboratory wind tunnel experiments, which indicate that mycorrhizal fungi have the potential to substantially increase the protective effect of newly seeded plants against wind erosion. For root balls of two plant species (Lolium perenne and Anthyllis vulneraria ssp. alpestris), we found that the wind-induced soil loss decreased significantly with increasing percentage of root colonisation by mycorrhizal fungi. The mean soil loss of non-mycorrhizal control samples was more than twice as high as the one of mycorrhizal samples for A. vulneraria, whereas no significant difference was observed for L. perenne. These results are all the more remarkable because there was no mycorrhiza-induced plant growth enhancement. On the contrary, mycorrhizal plants had significantly smaller root systems than non-mycorrhizal plants in both species. Above-ground biomass was significantly smaller in mycorrhizal plants than in non-mycorrhizal plants for L. perenne but only slightly smaller for A. vulneraria. This study demonstrates that mycorrhizal fungi are able to help newly seeded plants to decrease the wind erodibility of soil, even in cases when they do not increase plant growth. Copyright © 2011 John Wiley & Sons, Ltd.

The objective of this study was to evaluate the impact of rapidly changing land use on erosion and sedimentation in a mixed land use watershed in the Ozark Highlands of the USA. The research combines a geographic information system-based soil erosion modeling approach with land use change detection to quantify the influence of changing land use on erosion risk. Five land use/land cover maps were generated or acquired for a 20-year period (1986 through 2006) at approximately 5-year intervals to assess land use change and to predict a projected (2030) land use scenario for the West Fork White River watershed in Northwest Arkansas. The Unit Stream Power based Erosion/Deposition model was applied to the observed and predicted land use to assess the impact on erosion. Total erosion from urban areas was predicted to increase by a factor of six between 1986 and 2030 based on the projected 2030 land use. Results support previous reports of increased urbanization leading to increased soil erosion risk. This study highlights the interaction of changes in land use with soil erosion potential. Soil erosion risk on a landscape can be quantified by incorporating commonly available biophysical data with geographic information system and remote sensing, which could serve as a land/watershed management tool for the rapid assessment of the effects of environmental change on erosion risk. Copyright © 2011 John Wiley & Sons, Ltd.

The development and reversal of aeolian desertification have been widely recognised as the dominant causes of changes in the source areas of dust storms. The Alashan Plateau, which is near China's Hexi Corridor, is one of the major dust storm source regions in northern China. To investigate the relationship between climatic and anthropogenic factors and the development of aeolian desertification, we reconstructed the temporal and spatial evolution of aeolian desertification and the underlying processes from 1975 to 2007 using Landsat images and analysed the driving forces. The results show that aeolian desertified land in the study area covered 32 847·79 km² in 2007, amounting to 11·3 per cent of the total area, with an initial period of desertification expansion from 1975 to 2000 and a reversal of desertification from 2000 to 2007. On the basis of the analysis of effects of climate changes and human activities in the region, aeolian desertification was principally driven by human activities in this area; climatic variations had little effect on the area of severe desertification. Copyright © 2011 John Wiley & Sons, Ltd.

Most of Rwanda's wetlands are being reclaimed under government schemes with the aim of growing rice as the main crop. In the present study, information on farmers' knowledge and perceptions of agricultural wetland management was collected in Cyabayaga and Rugeramigozi wetlands. The two wetlands were selected as representatives for typical reclaimed wetland agriculture in Rwanda. They provide contrasts in both environmental and social terms. Three tools were used to investigate farmers' knowledge and perception of agricultural wetland management: (i) household survey; (ii) focus group discussions; and (iii) transect walk. The major constraints identified by farmers in the two wetlands were water shortage and lack of availability of improved seeds and high prices of fertilisers. The primary benefits from wetlands for farmers are income generation in Cyabayaga and food security in Rugeramigozi. The most commonly reported concern about the wetlands in the Cyabayaga and Rugerameragozi was that they are a source of malaria. Rice is an important crop in both wetlands, whereas farmers in Cyabahaga wish to continue cultivating rice, Rugeramigozi farmers prefer to grow rice only after it has been tested for its adaptability. Farmers have sufficient knowledge on the causes and the potential solutions to overcome most constraints. They know that soil suitability is closely related to relief. They classify soils by a number of criteria and choose crops accordingly. Any programme designed to address wetland management in the region will have to take account of farmers' knowledge and adopt a holistic view of wetland management. Copyright © 2011 John Wiley & Sons, Ltd.

Saline-sodic water is a by-product of coalbed natural gas (CBNG) production in the Powder River Basin of Wyoming, USA and is being beneficially used in places as irrigation water. This study evaluated effects of 2 years of natural precipitation on soil properties of a hay field after the cessation of managed irrigation with CBNG water. The hay field had been irrigated with only CBNG water [CBNG(NT)], CBNG water amended with gypsum [CBNG(G)] or gypsum plus sulfur via a sulfur burner [CBNG(GSB)] in combination with soil amendments—gypsum (+G), elemental sulfur (+S), and both (+GS). Results indicated that infiltration rates were the lowest on fields irrigated with CBNG(NT), followed by CBNG(G) and CBNG(NT)+G treatments (12·2, 13·2, and 13·5 cm h⁻¹, respectively). The CBNG(GSB)+GS treatment had the highest infiltration rates (33·5 cm h⁻¹). By the second year, salinity and sodicity of treated soils had decreased in the A-horizon of most CBNG-water irrigated plots, whereas in Bt₁- and Bt₂-horizons salinity generally decreased but sodicity increased; S and GS soil amended plots had higher profile salinities compared with NT and G soil treatments. Although Na⁺ leaching was observed in all fields that received soil and/or water amendments, CBNG(GSB)+GS plots had the lowest sodicity in the A- and Bt₁-horizons. Effective managed irrigation requires knowledge of site-specific soil properties, plant suitability, water chemistry, and amendments that would be needed to treat the CBNG waters and soils. This study indicates the greatest success was realized when using both soil and water amendments. Copyright © 2011 John Wiley & Sons, Ltd.

We hypothesised that digital mapping of various forms of salt-affected soils using high resolution satellite imagery, supported by field studies, would be an efficient method to classify and map salinity, sodicity or both at paddock level, particularly in areas where salt-affected patches are small and the effort to map these by field-based soil survey methods alone would be inordinately time consuming. To test this hypothesis, QuickBird satellite data (pan-sharpened four band multispectral imagery) was used to map various forms of surface-expressed salinity in an agricultural area of South Australia. Ground-truthing was performed by collecting 160 soil samples over the study area of 159 km². Unsupervised classification of the imagery covering the study area allowed differentiation of severity levels of salt-affected soils, but these levels did not match those based on measured electrical conductivity (EC) and sodium adsorption ratio (SAR) of the soil samples, primarily because the expression of salinity was strongly influenced by paddock-level variations in crop type, growth and prior land management. Segmentation of the whole image into 450 paddocks and unsupervised classification using a paddock-by-paddock approach resulted in a more accurate discrimination of salinity and sodicity levels that was correlated with EC and SAR. Image-based classes discriminating severity levels of salt-affected soils were significantly related with EC but not with SAR. Of the spectral bands, bands 2 (green, 520–600 nm) and 4 (near-infrared, 760–900 nm) explained the majority of the variation (99 per cent) in the spectral values. Thus, paddock-by-paddock classification of QuickBird imagery has the potential to accurately delineate salinity at farm level, which will allow more informed decisions about sustainable agricultural management of soils. Copyright © 2011 John Wiley & Sons, Ltd.

It is increasingly recognised that land degradation monitoring and assessment can benefit from incorporating multiple sources of knowledge, using a variety of methods at different scales, including the perspectives of researchers, land managers and other stakeholders. However, the knowledge and methods required to achieve this are often dispersed across individuals and organisations at different levels and locations. Appropriate knowledge management mechanisms are therefore required to more efficiently harness these different sources of knowledge and facilitate their broader dissemination and application. This paper examines what knowledge is, how it is generated and explores how it may be stored, transferred and exchanged between knowledge producers and users before it is applied to monitor and assess land degradation at the local scale. It suggests that knowledge management can also benefit from the development of mechanisms that promote changes in understanding and efficient means of accessing and/or brokering knowledge. Broadly, these processes for knowledge management can (i) help identify and share good practices and build capacity for land degradation monitoring at different scales and in different contexts and (ii) create knowledge networks to share lessons learned and monitoring data among and between different stakeholders, scales and locations. Copyright © 2011 John Wiley & Sons, Ltd.

Enhanced carbon fixation in soil crusts may facilitate the restoration of damaged ecosystems, but this requires greater knowledge of carbon fixation patterns and mechanisms. We measured the net photosynthetic rate (P_n) and estimated annual carbon fixation (ACF) in cyanobacterial–algal crusts after desert fixation in the Tengger Desert, northwestern China. The accumulated carbon fixation since the establishment of a restoration site was also calculated. In addition, stepwise regression analysis was used to study the relation between P_n and ACF and the physicochemical properties of crusts. Results showed that P_n was significantly higher at a more established 51-year-old restoration site (1·57 µmol m⁻² s⁻¹) than at a younger 15-year-old site (0·92 µmol m⁻² s⁻¹). The ACF also increased significantly with restoration time, but in two temporal phases, a slower ACF phase between 15 and 26 years of restoration (0·28–0·7 gC m⁻² y⁻¹) and a high ACF phase after 43–51 years of restoration (3·3 gC m⁻² y⁻¹). Stepwise regression analysis revealed that P_n was significantly correlated with chlorophyll a and crust cover, whereas ACF was only correlated with crust cover. Accumulated carbon fixation increased from 2·9 gC m⁻² after 15 years to 35·4 gC m⁻² at 51 years following establishment of the restoration site. The accumulated carbon fixation was positively correlated with soil organic carbon content. This study demonstrated that carbon fixation by cyanobacterial–algal crusts increased progressively after desert fixation. Artificial measures, like the establishment of these restoration zones, can facilitate the colonization and development of biological soil crusts and are an effective biological tool for desert soil restoration. Copyright © 2011 John Wiley & Sons, Ltd.

Despite the importance of desert dust at global and regional scales, its exact provenance is often unclear. The Taklimakan Desert in northwest China is a common source of high-frequency regional dust storms and is also a large source of global dust production. On the basis of field observations and the determination of the fraction of aeolian dust in surface samples, we characterized the relative intensity of windblown sand/dust processes in the Taklimakan and the volume of dust emitted (PM₁₀) during these processes. Major dust sources were degraded lands on the eastern desert margin, the Gobi and alluvial, fluvial and aeolian sediments occurring on the desert margin. These areas have high PM₁₀ emission capacity due to high-surface PM₁₀ concentrations and intensive windblown sand/dust activity. Despite having intensive windblown sand activity, the central desert had lower PM₁₀ dust emission capacity (<1·6 kg day⁻¹ m⁻² in spring, <0·08 kg day⁻¹ m⁻² in other seasons) due to lower surface PM₁₀ fraction. The dry Taitema Lake bed was a source of potentially high dust emissions (at least 4·4–17 kg day⁻¹ m⁻² for the monitoring period) due to the intensity windblown sand/dust activities, despite low PM₁₀ concentrations. The dry river beds on the southeastern desert margin had lower dust emission potential due to low PM₁₀ concentrations and windblown sand/dust activity. Most dust emission sources lie in the paths of prevailing winds, leading to aeolian dust transported to and deposited in the desert hinterland or Hotan, Yutian and Minfeng areas, where wind stream convergence leads to high-frequency dust storms. Copyright © 2011 John Wiley & Sons, Ltd.

The ongoing conversion and degradation of insular Southeast Asian peat swamp forests causes globally important carbon emissions and leads to loss of unique biodiversity. Little quantitative information is available on the dynamics of peat swamp forest conversion. In this case study, we present a time-series of peatland conversion and degradation in the Air Hitam Laut peatlands in Jambi Province (Sumatra, Indonesia), which included the Berbak National Park. High-resolution (10–60 m) satellite imagery was used to map land cover and degradation status for nine time slices between the 1970s and 2009. Nearly-pristine forest cover was shown to have declined in the study area from 90 to 43 per cent, inside the Berbak National Park from 95 to 73 per cent and outside the National Park from 86 to 25 per cent. Outside the protected area, 66 per cent of former nearly-pristine forests turned into degraded forests or unmanaged deforested areas. Large-scale oil palm plantations accounted for 21 per cent of the formerly nearly-pristine areas and small-holder agriculture for 8 per cent. The conversion to plantation has fast accelerated since 2002. Conversion from nearly-pristine forest to plantation typically took around 6 years, at times up to 10 years. Better understanding of conversion and degradation dynamics will allow for improved estimates of the implications of management planning decisions taken in peatland areas. Copyright © 2011 John Wiley & Sons, Ltd.

Local environmental conditions are known to be the most influential in landslide dynamics. Some variables, such as slope, elevation, lithology, vegetative cover, and soil type, are more common and influential than others. Every variable, except for vegetative cover, has been incorporated into many different statistical models as a continuous variable showing nuances and differentiation among the data. In regions where vegetative cover is the single most important variable in determining slope stability, a land cover classification cannot provide the level of information required for efficient modeling of landslide events. It is hoped that the surface cover index (SCI) can be used to numerically assess vegetative cover by using Landsat imagery and sub-pixel analysis. Two models utilizing simple raster calculations involving slope and the SCI were created. Each model was then assessed and validated for accuracy by using a user-created multi-temporal landslide inventory of the Dominical, Costa Rica area. Results determined that normalized inputs of slope and SCI can produce an algorithm with a high degree of accuracy and proved that the SCI can be used in assessing landslide hazard in a tropical forest environment. Copyright © 2011 John Wiley & Sons, Ltd.

Farmers' perceptions of soil fertility change were compared with observations on soil quality changes and crop performance in soils from a chronosequence representing a range of soil ages since conversion from forest to cropland (0 to 57 years). A majority of the farmers, 92 per cent, had observed a decline in soil fertility on their land. Farmers use crop yield, indicator plants, soil softness and soil colour to judge soil fertility. They identified 11 plants that they used to indicate high soil fertility and four plants that they used to indicate low soil fertility. There was a strong correlation (r = 0·96) between soil organic matter content (loss on ignition) and farmers' ranking of soil fertility based on colour and softness of soil samples from the chronosequence. The biotest experiment with maize showed an exponential decline in biomass production along the chronosequence, confirming the results of farmers' soil fertility ranking. In the biotest, total soil N predicted produced biomass well (r² = 0·95), whereas the relationship with soil available P (Olsen) was less obvious. Among the eight analysed plant nutrients in the maize leaves, N content was found to correlate best with biomass production (r² = 0·94). We conclude (i) that there is good agreement between farmers' knowledge and scientific indicators of soil fertility and (ii) that the major reason for declining soil fertility in Beseku is the decrease in N mineralization over time. Interventions should focus on supporting farmers to implement a diversified nutrient management strategy that can maintain or increase long-term productivity of the soil. Copyright © 2011 John Wiley & Sons, Ltd.

In an industrial/mining city, land use, ecosystem service values (ESVs) and local economy have a close relation. The study reported in this paper is conducive to optimising land use and to balancing ecosystem services and local economy. The aim is to provide useful information and advice for industrial/mining cities concerned with sustainable development. Wu'an, which is rich in mineral resources and an important energy supplier in Hebei Province, is selected as the study area. The ecosystem service value coefficients of industrial ecosystem and urban ecosystem are estimated adopting the cost method and applied to the city from 1996 to 2005. The temporal and spatial changes of the ESVs estimated within the entire ecosystem, sub-ecosystems and individual ecosystem services are analysed and discussed based on land use. The results show that land use in Wu'an had a great influence on the ESVs and especially the project of converting farmland into forests determined the entire ecosystem structure and functions. Additionally, the study shows the comparing relationships between ecosystem service values and local economy through various mathematical expressions. One significant relationship can be abstracted into an inverse curve (zone) under restrained conditions. The conclusions suggest that the rapid local economy development should build on a reasonable land use with emphasis on the high ecosystem services. Copyright © 2011 John Wiley & Sons, Ltd.

Wetlands inventory is one of the goals of conservation plans on a national scale and a global scale. Inventories are needed for long-term monitoring or for identifying lost wetlands and those where restoration is feasible. In this article, we present an updated inventory of the saline wetlands of Southern Monegros, Spain. We depicted the evolution of these saline wetlands, locally named saladas with a unique long-term retrospective study based on aerial photographs from 1927. Their inventory has been accomplished through a map analysis based on a geographical information system using aerial photographs and orthophotographs, topographic maps, unpublished local studies and field surveys. Remaining vegetation, changes in soil moisture and colour, and geomorphology have been the key features in identifying the saladas. Their changes in number, size and shape have been driven by human pressure, the main modifier of landscape in the last 80 years. The information gathered will contribute to the awareness of stakeholders and decision makers for their conservation as natural resources. Moreover, our large retrospective approach is a consistent base from which to propose the inclusion of the saladas of Monegros in the Ramsar list of Wetlands of International Importance. Copyright © 2011 John Wiley & Sons, Ltd.

Human-caused trampling that results from excessive recreational use has caused damage to soil and vegetation in forest ecosystems in the Belgrad Forest of Istanbul. The objectives of this study were to examine effects of exclosure on selected soil properties and to determine the recovery time required for soil characteristics in a broadleaf forest recreation site.

Litter biomass and topsoil (0–15 cm) were sampled in the forest, exclosure and recreational sites, and soil samples were analysed for saturation capacity, permeability, bulk density, total porosity, organic matter, root biomass, electrical conductivity and soil pH.

Results showed that saturation capacity, permeability, total porosity and organic matter increased whereas bulk density decreased significantly in the topsoil under the exclosure, and all these soil properties in the topsoil of the exclosure were greater than those of recreational site. When effects of main factors were compared, averaging over sampling year and soil sampling depth, soils from the exclosure had significantly greater saturation capacity, permeability, total porosity, organic matter and litter biomass and lower bulk density values than the soils from recreational site.

Six years of exclosure was effective in improving most of the soil properties in the topsoil. When topsoil and subsoil are considered together, it is obvious that a longer time period is needed for soil recovery in the forest recreational sites. Copyright © 2011 John Wiley & Sons, Ltd.

Soil management practices can have negative or positive effects on soil quality. Our objective was to assess the effect of long-term agricultural practices by evaluating selected soil physical and chemical properties. Soil samples were collected from two depths (0 to 15 and 15 to 30 cm) within a native pasture and an adjacent agricultural field that was being used for three different crop rotations. Soil quality was quantified using aggregate stability, bulk density, soil texture and available water content as physical properties and pH, electrical conductivity, organic matter and available phosphorus as chemical properties. The farmland soils were functioning at 71 and 70 per cent of their full potential at the 0- to 15- and 15 to 30-cm-depth increments, respectively, whereas those from the pasture were functioning at 73 and 69 per cent, respectively. The assessment showed substantial loss in soil organic carbon following 50 years of farmland cultivation. Tillage and fertilizer applications were presumably the primary reasons for weaker spatial dependence within farmland at the 0- to 15-cm depth. Grazing was postulated as the main reason for weaker spatial dependence within the pasture soils at the 15- to 30-cm depth. Overall, we conclude that 50 years of cultivation has not caused soil quality to decline to a point that threatens sustainability of the agricultural fields. Copyright © 2011 John Wiley & Sons, Ltd.

Experimental restoration may both accelerate and elucidate natural processes of succession on degraded agricultural land by offering insight into factors that influence rates of succession and the composition of resulting communities. A novel study in restoration of degraded tropical agricultural land in coexistence with cattle ranching activities was established in southern Veracruz, Mexico. The experimental planting of 16 mixed-species stands of 18 pioneer and late-successional tree species was established from September to November 2006 on an eroded hillside pasture with an elevational gradient from 182 to 260 m and heterogeneous soil depths. An unusually severe dry season in 2007 killed 72 per cent of the seedlings: least squares regression suggested that survival of six pioneer and 12 late-successional species was mainly explained by initial basal diameter at planting followed by soil depth for pioneers and by elevational position on the hillside for late-successional species. Individuals with larger initial size at planting (>4 mm basal diameter), regardless of germination size in a growing house, survived better probably because larger seedlings developed deeper roots that found fissures in substrate underlying thin soils. Interestingly, seedlings small at planting (<4 mm basal diameter) survived as well as large seedlings in deeper (>19 cm) soils, but virtually, all small seedlings died on thin soils (<18·5 cm). Mortality in restoration plantings can be reduced by planting large seedlings of a mix of pioneer and late-successional species, recognizing that soil depth is a key criterion for survival of the smallest seedlings in a cohort. Copyright © 2011 John Wiley & Sons, Ltd.

The analysis of the spatial variability of soil properties is important for land management and construction of an ecological environment. The objectives of this study were to investigate the spatial variability of saturated hydraulic conductivity (K_S), total porosity (TP), capillary porosity (CP) and bulk density (BD) in relation to land use in a 0·54 km² watershed on the Loess Plateau. Topsoil samples (0–5 cm) from 154 sites within the watershed were collected and analyzed by classical and geostatistical statistics in the summer of 2009. The results from the classical statistical analyses indicated that TP, CP and BD had low variability whereas K_S had high variability with the watershed. Farmland had significantly lower BD and higher TP and CP than grassland, shrubland and woodland (p < 0·05). Geostatistical analyses revealed that the K_S semivariogram was best fit by a spherical model, the CP semivariogram was best fit by an exponential model and the TP and BD semivariograms were best fit by Gaussian models. The nugget to sill ratios and fractal dimension values indicated that all four soil properties had strong spatial dependence. Moran's I analysis showed that a 100-m sampling interval would be adequate for detecting the spatial structure of the four soil physical properties within the watershed. Spatial interpolation maps could provide useful information for precision agriculture practices and ecological management. Copyright © 2011 John Wiley & Sons, Ltd.