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Keywords:

  • soil fertility;
  • fertilizers;
  • agroforestry;
  • green revolution;
  • millennium villages;
  • Millennium Development Goals

Abstract

  1. Top of page
  2. Abstract
  3. Introduction
  4. Key Constraints to Increasing Production
  5. Approaches to Soil Fertility Improvement
  6. Other Complementary Interventions
  7. It Can Be Done: Emerging Evidence
  8. Conclusion
  9. Acknowledgments
  10. Conflicts of Interest
  11. References

Agricultural development lies at the heart of poverty reduction and increased food security of most developing nations. Sub-Saharan Africa (hereafter referred to as Africa) is, however, the only region in the world where per capita agricultural productivity has remained stagnant over the past 40 years. In Asia and Latin America, the use of tailored techniques and technologies has transformed agricultural practice and its productivity, leading to what has been called the “green revolution.” The dissemination of uniquely African green revolution technologies has not occurred on the continent. This chapter will argue that the same results in increased productivity and food security can be achieved in Africa if the appropriate investments are made in key interventions: soil fertility improvement, improved seeds, water management, market access, extension services, access to credit, and improvements in weather forecasting. Where these have happened, even partially, the outcome has been remarkable. However, bringing them to scale in ways that sustainably increase agricultural productivity and alleviate poverty requires increased investments and innovative institutional arrangements. Fortunately, several research and development projects on the continent, including the Millennium Villages Project, are providing valuable insights. Finally, this chapter outlines the key remaining challenges.


Introduction

  1. Top of page
  2. Abstract
  3. Introduction
  4. Key Constraints to Increasing Production
  5. Approaches to Soil Fertility Improvement
  6. Other Complementary Interventions
  7. It Can Be Done: Emerging Evidence
  8. Conclusion
  9. Acknowledgments
  10. Conflicts of Interest
  11. References

Many of the rural poor worldwide are smallholder farmers, and in most of South and Southeast Asia, and in much of sub-Saharan Africa (hereafter referred to as Africa), agriculture is dominated by smallholders.1,2 But why do smallholders remain poor? One common answer is that despite being relatively efficient users of resources, they remain poor because most poor countries provide them with only limited technical and economic opportunities to which they can respond. This is particularly the case in Africa, the only region in the world where per capita agricultural productivity has remained stagnant over the past 40 years.3 This has resulted in food insecurity, growing dependence on food aid, and increasing poverty on the continent. Food insecurity, a fundamental measure of poverty, is one of the most pressing problems facing the continent. The food crisis in Africa now is similar to that of Asian countries in the 1960s and is characterized by a high threat of famine, chronic food deficiency, rampant poverty, rapid population growth, weak institutions, corrupt governments, and Western pessimism.4

How was the Green Revolution in Asia successful against this background? According to the architects of the India Green Revolution,5 it worked because of major technological and institutional changes. The absence of substantial investments in agriculture, a phenomenon in most African countries, was a major factor responsible for the general stagnation of agricultural production in India in the 1960s. Where similar investments were made in Africa, the Green Revolution indeed happened. Examples are the spurts in production that took place in Zimbabwe before and after independence,6 in Kenya from independence into the 1970s,6,7 in Ethiopia after the fall of Derg,7 and in Nigeria after the banning of maize and rice imports.7

There is ample evidence that smallholder farming can be productive and engage in competitive markets when provided the necessary support. This can have considerable effects on poverty reduction. For most observers, tackling poverty means boosting smallholder agriculture as a way of driving broad-based economic growth and employment across a range of agricultural and nonagricultural activities.8 It is also essential to reducing the growing number of undernourished people on the continent, which is estimated to be 212 million,3 about a third of the population. In strategic terms, smallholder farming is generally viewed as indispensable to development as a whole, and agricultural growth in poor rural areas can drive poverty reduction through three broad mechanisms9:

  • • 
    the direct effects of increased agricultural productivity and incomes on the rural poor,
  • • 
    benefits of cheaper food for both the urban and rural poor, and
  • • 
    agriculture's contribution to economic growth and the generation of more opportunities in the nonfarm rural sector.

Over time, these factors can lead to structural economic change, characterized by the increased importance of the nonfarm economy and the decreasing relative importance of the agricultural sector. In this respect, smallholder agriculture is often seen as a win–win option for equitable growth.9,10

After nearly two decades of neglect, agriculture is back on the policy agenda, for donors and poor countries alike.11,12 The most important reason for this development, accordingly, is a common understanding that economic growth is the main vehicle for reducing poverty and that growth in the agricultural sector, including smallholders, drives this growth and plays an important role in overall economic development. The most severe and intractable poverty in the world is in Africa, where more than half are smallholder subsistence farmers.12 It is against this background of growing food insecurity and poverty, and the realization of the great potential that agriculture holds, that former United Nations Secretary-General Kofi Annan in July 2004 highlighted what he called “Africa's 21st Century Green Revolution” to achieve the Millennium Development Goals by 2015.13 He called for special attention to farming systems in areas largely disconnected from functioning markets. This applies equally to remote areas in Africa, Asia, and Latin America.

Increasing the productivity of smallholder agriculture requires bringing to scale several practical interventions. This chapter highlights the key interventions needed and examines their scientific underpinnings. The chapter is divided into four parts, beginning with the introduction. The next section discusses the key biophysical constraints to increasing production. The third highlights practical options to manage soil fertility, which is increasingly recognized as the fundamental cause of the declining productivity.3 The fourth section addresses other complementary interventions essential for sustainable success, such as improved germplasm, water management, weather forecasting extension, markets, and microfinance. The final section demonstrates the possibility of scaling effects up to national levels, highlighting some of the approaches and effects of the Millennium Villages Projects. In the conclusion, we emphasize that the knowledge base to reverse the precarious food situation in Africa is available and that there is room for targeted input subsidies in the investments required.

Key Constraints to Increasing Production

  1. Top of page
  2. Abstract
  3. Introduction
  4. Key Constraints to Increasing Production
  5. Approaches to Soil Fertility Improvement
  6. Other Complementary Interventions
  7. It Can Be Done: Emerging Evidence
  8. Conclusion
  9. Acknowledgments
  10. Conflicts of Interest
  11. References

African farming systems are diverse, with many different carbohydrate staple crops, such as yams (Diascorea sp.), cassava (Manihot esculenta Crantz), bananas and plantains (Musa spp.), and sweet potato [Ipomea batatas (L.) Lam.] generally in the more humid areas, apart from the widespread cereal crops maize (Zea mays L.), sorghum [Sorghum bicolar (L.) Moench], and millet [(Pennisetum glaucum (L) R. Brown]. There is also diverse range of livestock species, including fish. Given this rich diversity, one wonders why Africa cannot feed itself. There are several reasons, key among them declining soil fertility, inadequate use of improved germplasm, and limited irrigation that severely limit production potential.3

Soil Fertility

Little progress can probably be achieved in smallholder farming in Africa without first addressing the problems associated with soil and land degradation. About 55% of Africa's land area is unsuitable for agriculture. Only 11% of the continent, spread over many countries, has high-quality soil that can be effectively managed to sustain more than double its current population.14 Most of the remaining arable land is of medium or low potential, with at least one major constraint for agriculture. This land is at high risk of degradation under low input systems. By 1990, soil degradation was estimated to have affected 500 million ha, or 17% of Africa's land.15 Susceptible dry lands (arid, semiarid, and subhumid aridity zones), covering 43% of Africa, are the worst-affected areas, affecting 485 million people.16 Approximately 65% of agricultural land, 31% of permanent pastures, and 19% of forest and woodland in Africa were estimated to be affected by some form of degradation in 1990.15

The current situation is undoubtedly worse. Soil moisture stress inherently constrains land productivity on 86% of soils in Africa,14 but soil fertility degradation now places an additional serious human-induced limitation on productivity. Other problems commonly noted3 include the following: large human disease load, including human immunodeficiency virus (HIV)/AIDS; large rural inland population; no major river basins for irrigation; inadequate policy frameworks (although greatly improving); and markets that do not work for the poor.

The use of inorganic fertilizers is one way to improve crop yields. In developing countries outside those in Africa, the use of fertilizer accounted for a 50%–75% increase in crop yields from the mid-1960s.17 Unfortunately, in Africa only a small proportion of farmers use fertilizers and the amounts used are often inadequate (Table 1). On average, each hectare receives less than 9 kg of nitrogen and 6 kg of phosphorus. Typical crop requirements per hectare are at least 60 kg of nitrogen and 30 kg of phosphorus. Chemical fertilizer use per hectare of farmland in Africa is about 10% of the world's average, by far the lowest. The current state of Africa's fertilizer use is, indeed, unsustainable. This results in nutrient depletion, a situation complicated by the low inherent fertility of many African soils, of which more than 80% have chemical or physical limitations to crop production.18

Table 1.  Use of inorganic fertilizers in sub-Saharan Africa
CropFarmers using (%)Amt (kg/ha)
  1. Source: Adapted from Reference 4.

Maize4714 
Cassava61.6
Sorghum456.6
Rice307.4

Fertilizer use is low largely because of its high cost (Table 2), and it contributes significantly to the unprofitable nature of smallholder farming that is often seen in much of Africa.19 Few subsistence farmers can afford to use fertilizers, which in many parts of Africa can cost nearly four times as much as they do in North America or Europe.20 Transport costs are about seven times higher in Africa than in the United States (U.S. dollars in tons per kilometer). For example, transport and related costs (import duties, demurrage, and many taxes) more than double the international price by the time fertilizers reach the farmer in rural Malawi.21 Thus, smallholder farmers in Africa have not benefited much for the past 25 years in real international prices decreases of about 38% for nitrogen and more than 50% for phosphorus.21 An important driving factor for this is the high transport cost. For example, the comparative costs of moving 1 ton of fertilizer 1000 km are US$15 in the United States, US$30 in Asia, and US$100 in Africa.22 Similarly, the cost of moving 1 ton of maize from Iowa (USA) to Mombasa (13,600 km) is US$50, and from Mombasa to Kampala (900 km) is US$100.

Table 2.  Selected international fertilizer (diammonium phosphate) prices for 1988/1999
LocationPrice per ton (US$)
  1. Source: Adapted from Reference 4.

CIF Mombasa248
Kansas (USA)260
Pakistan283
Bangladesh286
South Africa348
Central Ethiopia350
Central Kenya415
Malawi470
Uganda550

Estimates in the mid-1990s show that every country in Africa had a negative nutrient balance in its soils, meaning that the amount of nitrogen, phosphorus, and potassium added as inputs was significantly less than the amount removed at harvest or lost by erosion and leaching.3 This is in sharp contrast to the nutrient overload of soils in the northern hemisphere, although this poses great environmental threat. It also contrasts with average fertilizer nutrient use rates of 150 kg/ha in the developing countries of Asia and 75 kg/ha in Latin America. Since 1980, fertilizer consumption in Africa has increased only 0.64%, even though the population grew by 75%—from 345 million to 607 million people. Over this same period, fertilizer consumption in the Association of South East Asian Nations region of Southeast Asia—with a slightly smaller total population than Africa—grew at more than 12% per year. Because of low use of inputs, yield increase with improved crop varieties is estimated at 88% in Asia but only 28% in Africa.23

Irrigation and Water Harvesting

Soil moisture and nutrients are complementary inputs. This is particularly pertinent in Africa, where farm-level costs of chemical fertilizers are high and rainfall is unreliable in many areas. High yields require ample fertilizer, high-quality seeds, and other costly inputs. Yet farm-level expenditures for fertilizers, seeds, and other inputs are risky in areas where rainfall is uncertain and crops often fail because of drought. This conundrum, in which farmers cannot afford to apply the inputs required to achieve high yields, explains a fundamental difference between crop production in Asia and Africa. In Asia, more than half of arable land is irrigated and the average annual application of fertilizer is about 40 kg/ha of arable land. In Africa, less than 5% of farmland is irrigated and the average fertilizer application is less than 10 kg/ha.24 Farming is at the mercy of highly variable weather conditions. In some regions, weather extremes are expected to be exacerbated as a consequence of long-term climate change.

Innovations in water harvesting and reuse, development of small-scale irrigation methods, and use of water-saving irrigation systems that enable careful application of nutrients are needed to improve water and nutrient use efficiency. Low-cost irrigation technologies have helped millions of small-scale farmers in Asia to gain access to shallow groundwater, with consequent increases in agricultural productivity, income, and household food security. Efforts to develop greater use of groundwater include the distribution of low-cost treadle pumps and drip-irrigation kits in Kenya, Tanzania, Zambia, and other countries.25 At present, surface water is the primary source of irrigation in most of Africa. Thus, surface water storage systems are needed to optimize the use of river water for much of Africa.26 However, the cost of construction and the potential environmental effects might preclude development of surface water storage in some areas.

Improved Germplasm

Another key factor to increasing agricultural productivity in Africa is reducing the large yield gap between actual and potential yields. This gap stands at more than 50% for maize, a staple food crop of many countries on the continent. The same is true for other important crops in the region, such as cassava, sorghum, and rice.4 This yield gap is, indeed, evidence of the untapped potential for increasing production and productivity of agriculture in Africa.

Adoption of improved germplasm is generally low in Africa (Table 3). Even for maize, where adoption rates average about 57%, the gap is widening between research gains and adoption.27 Cassava is picking up fast, although it is still under 40%. Several factors can be advanced for the low adoption of the many technologies available. An important one is the high price of inputs (fertilizers and pesticides), no liquidity or credit facilities, no access to supplementary irrigation—all contributing to the high risk of farming.11 Furthermore, insecure land tenure rights often serve as a serious disincentive for farmers to invest in soil amendments or soil and water resource conservation measures.28

Table 3.  Germplasm quality adoption rates (%) in sub-Saharan Africa
SeedMaizeCassavaSorghumRice
  1. Source: Adapted from Reference 4.

Traditional43618671
Improved57391429
Total100 100 100 100 

Extension Services

There is, indeed, need to revitalize extension if agricultural production is to increase. Even where techniques and technologies are relevant and available, smallholder farmers often have no access to them. For this reason, extension systems and input distribution systems are mutually reinforcing—the contribution of extension to agricultural productivity growth depends on functioning input distribution systems and vice versa. Agricultural technologies are also rapidly changing. Farmers need to be made aware of what technologies work best, know how to use them, and generate effective demand for viable new technologies to provide signals to input distribution system to supply them.

Unfortunately, agricultural extension in Africa is poor and declining in many countries. Where extension services exist, the ratio of agricultural officers on the ground to farmers is often huge. Several factors have contributed to declining extension services—retrenchments after the structural adjustment programs, HIV/AIDS, conflicts, and civil wars. Private extension provision is generally skewed toward well-endowed regions and high-value crops.28 Remote areas and poor producers, especially those growing low-value crops, with little marketable surplus are poorly served.29 Fortunately, nonprofit private providers are increasingly targeting these communities.

Access to Markets

Over the past 20 years, most African governments have carried out reforms to deregulate agricultural markets and reduce the role of state enterprises. Although the reforms have had many favorable results, their effect has, however, been muted by partial implementation and structural constraints.30 Without well-functioning markets, it would be difficult to achieve the goals desired. The challenges include building connections and trust between actors in the market chain; supporting small-scale producers to collaborate and coordinate to achieve economies of scale in transactions with buyers or suppliers; increasing channels of information and market intelligence to rural producers; and helping rural producers access better information to understand the product, process, and delivery standards required by buyers.

Access to Credit Schemes

Financing problems are pervasive in Africa, affecting all sectors of the economy and all levels of the input sector. A successful input credit system in the smallholder sector could have an important payoff for poverty alleviation. The current agricultural credit problem in Africa is typically characterized as one of market failure associated with imperfect information in the presence of risk.21 Market failures occur because it is costly to screen input credit applicants, and institutions for contract enforcement are weak; insurance is absent (for similar reasons); and farmers lack collateral for loans. This obstacle affects nearly all smallholder farmers, most of whom in Africa are women. Gendered differences in wealth result in women's lowered access to cash and credit that is needed to acquire fertilizers and other agricultural inputs.31 Even then, provision of credit is not assured because of their limited availability of collateral. Efforts to correct this problem include regrouping farmers into strong cooperatives that can provide adequate guarantees to banks.

Approaches to Soil Fertility Improvement

  1. Top of page
  2. Abstract
  3. Introduction
  4. Key Constraints to Increasing Production
  5. Approaches to Soil Fertility Improvement
  6. Other Complementary Interventions
  7. It Can Be Done: Emerging Evidence
  8. Conclusion
  9. Acknowledgments
  10. Conflicts of Interest
  11. References

Given the pervasive problem of soil degradation and infertility across much of Africa's agricultural area, many now recognize the restoration of soil fertility as the key entry point to increase agricultural productivity in many African smallholder farms.3,11 To deal with the various conditions and circumstances of smallholder farmers, a wide range of soil fertility management innovations and approaches is needed. Fortunately, there is an array of proven technologies to replenish soil fertility in Africa,32 ranging from primary use of organic inputs for the poorest to combinations of organic and inorganic fertilizers for the less-deprived groups. The choice of technology depends on what the lowest-cost option to provide nutrients at the farm-gate level is. Some promising options are discussed in the next section.

Integration of Organic and Inorganic Fertilizers

Based on many multilocational studies, a consensus33 has now emerged that the highest and most sustainable productivity gains per unit nutrient added are from mixtures of inorganic inputs (fertilizers) and organic inputs. This consensus moves away from the fertilizer package approach, which has often failed in the region. But this adds to the existing challenge of ensuring fertilizer availability and the new challenge of building up the farmers' ability to produce organic matter.

Promising organic soil fertility strategies include agroforestry technologies, such as improved fallows with fast-growing leguminous trees and cover crops that mobilize atmospheric nitrogen,34 biomass transfer from nutrient-mobilizing plants, such as Tithonia diversifolia,35 compost, crop residues, and animal manure. The nutrient content, especially phosphorus in manure, can be improved tremendously when livestock is fed with leguminous tree fodder.36 The leguminous trees technologies help improve soil fertility, increase yields, control weeds, and provide fodder and firewood, and they serve as stakes for higher-value crops, such as tomatoes and climbing beans. The agroforestry technologies also help the environment by increasing biodiversity, sequestering carbon, and protecting watersheds. The use of agroforestry and other organic fertilizers would still require the use of mineral fertilizers, especially phosphorus. This can come from more conventional phosphorus fertilizers or from finely ground phosphate rock, and there are several “reactive” rock deposits in Africa that could be further exploited.37

The effects of this integrated approach to soil fertility management are best demonstrated by agricultural research programs in western Kenya, a densely populated region with more than 1000 people per square kilometer in some locations.32 This region exemplifies the problem of low and declining soil fertility, and the continued threat to land resources is compounded by the need to raise food production and reduce poverty. Here, attainment of food security is intrinsically linked with reversing agricultural stagnation (due largely to low and declining soil fertility), safeguarding the natural resource base, slowing population growth rates, combating the negative effects of HIV/AIDS pandemic on the community, and reducing poverty.

To remedy this situation, a low-cost integrated soil package was piloted by the World Agroforestry Centre and other partner organizations.32 The key components of the package were the following: recapitalize phosphorus-deficient soils; supplement phosphorus dressings with organic manure to increase phosphorus use efficiency; use existing on-farm organic resources (including biomass transfer) to supply nitrogen to crops; use improved fallows of agroforestry species to replenish soil nitrogen and reclaim Striga-infested soils; supplement organic sources of nitrogen with inorganic nitrogen fertilizers for high crop yields; and support phosphorus and nitrogen replenishment with a set of accompanying technologies, including high-quality crop seeds.

Thousands of farmers adopted the technologies, and within only one growing season, the yield of maize (the staple food crop) increased two to three times over the typical yields of 1–2 tons/ha or less (Fig. 1). In addition to recycling nitrogen at 100–200 kg/ha, the tree fallows also provide multiple benefits, such as in situ fuelwood production, capture of leached nitrates, recycling of other nutrients, and Striga control.32,34 The improved maize yields also motivated farmers to diversify and access improved varieties of various crops, such as cassava, sweet potatoes, beans, sorghum, and fruits, such as mangoes, avocado, and passion.

image

Figure 1. Effects of improved fallows and Minjingu phosphate rock on maize grain yield under farmers' management conditions in western Kenya.38

Download figure to PowerPoint

A spillover effect of the increased crop yields was access to lunch by the schoolgoing children in one of the villages. The villages became learning centers for others in the region.39 They also became field laboratories for institutional and technical innovations by researchers and farmers. This greatly contributed to the success of the project. The project was, however, only 3 years long and ended before farmers could sustain efforts to procure the inputs necessary and support community-based farmer-to-farmer dissemination systems. Fortunately, the Millennium Villages Project has now taken over the initiative and is promoting the same agroforestry interventions.40

Conservation (or Zero) Tillage

Conservation tillage (CT) is a practice that can be promoted in various forms across several wealth classes of farmers. It requires little or no soil disturbance and has many production and resource conservation advantages. Farmers can plant crops sooner after the first rains, in effect gaining a longer growing season. Crop residues left on the ground form mulch that slows rainwater runoff and reduces erosion, improving soil organic matter content and water infiltration and retention. Over time, this increases CO2 sequestration, improves soil structure, reduces weed and pest problems (in conjunction with crop rotations), and enhances nutrient mobilization.41 Building soil organic matter and nitrogen benefits, however, takes a long time and may occur only when inorganic fertilizers are applied to increase plant biomass production.42

Mulch management is perhaps the most demanding aspect of CT. Farmers must preserve the mulch by controlling bush fires and keeping livestock from feeding on crop residues. To accomplish this, a range of practices is recommended, from the use of green manure and leguminous tree cover crops to cover crops that control weeds and produce mulch, to CT systems that build around the use of herbicides. CT is knowledge intensive—its success depends more on what the farmer does (management) than the inputs that he or she applies. Spreading the adoption of CT among smallholder farmers requires emphasis on information flow and knowledge development to and among farming communities. It involves researchers and extension agents' working together with farmers and other agents to develop locally adapted conservation agriculture techniques. It requires the participation of multiple partners. This goal is being carried out through the African Conservation Network, which has also provided a comprehensive review of the knowledge base so far.43

Dual-purpose Grain Legumes

In Africa's dry lands, a promising technology is the dual-purpose cowpea cultivars developed by the International Institute of Tropical Agriculture in collaboration with the International Livestock Research Institute that provide both grain for human consumption and fodder for livestock in the dry season. Assessment of effects shows that farmers obtain substantial benefits by adopting the dry-season dual-purpose cowpea.44 These include food security during a critical period of the year, cash income, fodder, and in situ grazing after harvesting in periods when the prices of cowpea grain peak and when good-quality fodder is scarce.

Other Complementary Interventions

  1. Top of page
  2. Abstract
  3. Introduction
  4. Key Constraints to Increasing Production
  5. Approaches to Soil Fertility Improvement
  6. Other Complementary Interventions
  7. It Can Be Done: Emerging Evidence
  8. Conclusion
  9. Acknowledgments
  10. Conflicts of Interest
  11. References

The interventions presented in the previous section can increase agricultural productivity and generate income. There are, however, several complementary interventions that are needed to make the systems self-sustaining, reliable, and long lasting. These complementary interventions are both technical and institutional and are discussed in the next section.

Improving Fertilizer Delivery Systems

As part of structural adjustment programs, almost all African governments ended subsidies and direct participation in fertilizer supply in the late 1980s.21 It was hoped that this action would stimulate development of a private sector that would lead to improved efficiency in fertilizer delivery systems, which eventually would translate into more accessible prices. Usually, this has not happened. For many reasons—some related to poor transport systems and others to unfavorable economic policies and conditions—the profitability of using fertilizers on key food and fiber crops in Africa has worsened over the past 15 years.30 Fertilizer prices in Africa are two to three times higher than what they are in international markets (Table 3).

Cost reductions can be achieved all along the supply chain: from procurement to shipping of fertilizer, to unloading and bagging, to transportation and retailing at the farmer level. Reaching this goal requires changes in some national policies currently in place. Usually, policy changes are not costly but require better regulations and enforcement. Governments also need to participate more actively in private fertilizer sector development. Easier access to foreign exchange and affordable interest rates are important stimuli for fertilizer importers. The government of Rwanda is pioneering this approach.45

Fertilizer delivery systems focusing on business and technical farmer advisory training can also help input dealer (stockist) networks at the grassroots level. This endeavor should focus on the product and packaging needs of smallholder farmers, not only in fertilizers but also in improved seeds, simple farm equipment, crop protection chemicals, and veterinary supplies. An input credit guarantee scheme would help link local input dealers to wholesalers and banking institutions. Success is remarkable where this happened, such as the agrodealers pilot project program in western Kenya pioneered by the Rockefeller Foundation.46

Social Investments in Land and Watershed Rehabilitation

More than half of the poor in Africa live on lands that are environmentally fragile,47 and these people rely on natural resources over which they have little legal control. Land-hungry farmers result to cultivating unsuitable areas, such as erosion-prone hillsides and semiarid areas, where soil erosion is rapid and tropical forests where crop yields on cleared fields drop sharply after just a few years. Many of these marginal lands are not only critical to livelihoods of the poor but they also play critical roles in watershed and biodiversity conservation. Moreover, the poor are the most vulnerable to the effects of ecosystem degradation, climate variability, and natural disasters.

In promoting agricultural intensification in these lands, it will be essential to fully recognize these multiple roles. Doing so implies promoting natural resource conservation interventions that are implemented at the ecosystem or landscape level. Such approaches can also directly contribute to poverty reduction and improved food security.48 Moreover, such investments could generate positive international public goods from positive environmental externalities.32 Capital investments are different from subsidies in that they have a profit expectation in the long term—an explicit return on investment—whereas subsidies are a short-term removal of constraints. However, active steps are needed to achieve joint poverty reduction, conservation, and agricultural development objectives.

Thus, food-for-work programs now common in many African countries should be organized with those rural agricultural communities located in highly environmentally degraded areas in mind, with a focus on high-priority ecoconservation reclamation works. These programs would provide supplemental employment during the hunger season to some of the most food-insecure people. It is suggested that the in-kind food payments be sourced from domestic production in food-surplus areas of the country. Thus, multiple development goals could be accomplished: reclamation of severely degraded watersheds, increased food security, and expanded market demand for domestically produced food staples.

Improving Water Management

Lack of investment on irrigation infrastructure implies that most of the population in Africa depends on rain-fed agriculture for their food production, mostly in the form of smallholder subsistence agriculture. Also, high inter- and intraseasonal rainfall variability leads to increased risk of frequent crop failures. Reducing this risk provides not only the immediate benefit of food security but also incentive for farmers to invest in farming as a business.

Another complicating factor to the water scarcity in rain-fed African agriculture is the large percentage of nonproductive water flows in the water balance. To amplify this, the hydrological cycle can be partitioned into two parts48: “green” water, or return flow of water to the atmosphere as evapotranspiration, and “blue” water, or the total runoff including the sum of surface runoff and groundwater recharge. Rainfall in Africa can be seen as partitioning into different flows: soil evaporation in this region of the world is in the range of 30%–50% of the incoming precipitation; surface runoff usually amounts for 10%–25%; and drainage is in the range of 10%–30%. Productive green flow, therefore, amounts to only 15%–30% of incoming precipitation.48

Water harvesting, used in its widest definition of collecting water for productive use, is an entry point for addressing the water constraints of farmers in Africa.49 Along with the nutrient and soil erosion control interventions discussed before, water harvesting is key to minimizing the risks of crop failures for rain-fed agriculture.

There are many examples of water management technologies (both traditional and modern) in use in Africa, although not nearly covering the real need for supplementary irrigation. The main examples of traditional technologies49 are

  • • 
    water harvesting, typically using open-pan floodwater harvesting;
  • • 
    swamp irrigation (commonly used throughout west Africa);
  • • 
    hill irrigation (mainly in the hilly areas of central Ethiopia, Tanzania, and Malawi); and
  • • 
    groundwater harvesting.

Improved traditional methods incorporate some level of technology to make the irrigation process more efficient. The main examples are open canals to manage surface irrigation, storage reservoirs, and buried pipelines. The last is an innovation aimed at replacing canals, improving water supply management, and reducing wastage, but this practice is not extensively used in Africa.49

Modern technologies refer mainly to on-farm irrigation systems, such as sprinkler systems, trickle irrigation, introduction of piped distributions systems for surface irrigation, and the use of treadle pumps. All these are unlikely to be taken up by poor subsistence farmers because they get financial support. Such investments are likely to increase the area under cultivation, bridge the dry-season food and income deficits, and contribute significantly to reducing poverty.

In the African context, small-scale and technically simple water management systems have proven to be more successful than large ones owing to their lower cost and greater ease of operation and maintenance.11 Low-cost systems attempt to retain the benefits of conventional systems while removing barriers to adoption. Most of the innovations in this area have been in trickle irrigation led by India, Nepal, and China.48 These countries have emphasized the establishment of national manufacturing capacity and development of systems that do not rely on automatic control or other labor-saving devices, helping generate demand for local skilled labor. In Africa, the treadle pump49 is particularly becoming popular with farmers in many countries for dry-season vegetable production. This is particularly so in urban and periurban areas that have better access to markets. Similar efforts, as those of Asia, are needed in Africa in their production and skill development.

Increasing Access to Improved Germplasm

Using improved seed and planting materials undoubtedly improves productivity. Yet it is important to keep in mind that it has to be done with the simultaneous and judicious use of other complementary inputs—fertilizer, water, and pest and disease control. Improved germplasm alone will not do it. Where this combination has been adopted, yields have been improved enormously.10 In addition to cereals, there is need to improve and promote the greater use of tuber crops (especially cassava and sweet potatoes), as well as bananas and plantains. They require fewer inputs and management than cereals and help to improve food security. More attention needs to be given to grain legumes, such as cowpeas and pigeon peas, that provide protein for the family and fodder for livestock and help to improve soil nitrogen content and control pests and diseases if used within crop rotations.50 Improving livestock productivity is essential. In many areas of Africa and Asia, livestock and livelihoods are closely related because livestock strengthen both nutrition and income security.

Investing in Agricultural Research and Extension Services

Sustainable food security requires socially and environmentally responsible intensification of agriculture, not extensification. Unlike the Asian Green Revolution, farming techniques exist today that permit environmentally friendly intensification, such as agroforestry and small-scale water management. The challenge is ensuring access to information and new technologies. With respect to technologies, those that have multiple products are likely to be more attractive to resource-poor farmers. An example is the multipurpose cowpea that feeds people, livestock, and soils. The integration of these varieties in the mixed crop-and-livestock production systems of northern Nigeria has helped produce more food on less land with fewer resources.44 Another example is the integration of fast-growing leguminous trees and shrubs that improve soil fertility but also generate fuelwood.34 This technology is now adopted by thousands of farmers in the eastern and southern regions of Africa.20 A key challenge is how best to provide extension services to farmers; doing so requires a better understanding of the roles of private and public sectors.

Although the private sector can play a significant role, emerging evidence29 suggests that, usually, private extension is not a substitute for public extension. It also suggests that the public sector should fund extension significantly but in ways that do not duplicate services already provided by sustainable alternative extension providers. An approach toward this goal is used by the National Agricultural Advisory Services project of Uganda that aims to transform the existing publicly delivered national-level extension to a decentralized, largely farmer-owned, private-sector advisory services system.51 Success factors appear to be enabling beneficiaries (local governments and farmers) to contract with qualified institutions or entities to deliver advisory services that will permit great flexibility in the types of delivery mechanisms that might be used to meet the needs of a heterogeneous population of beneficiaries.

Formal agricultural extension is not the only source of new technical knowledge. Experience shows that farmers do not passively wait for outside solutions but rather actively experiment and innovate with agricultural and natural resource management practices. Their creativity is one of Africa's major underexploited resources.52,53 A major advantage of innovations by farmers is that they are often readily acceptable to their fellow farmers and are site specific. The introduction of a farmer innovation approach can significantly improve the performance of extension services. Farmer-to-farmer exchanges and study visits are also effective in exposing farmers to new ideas, particularly in the field of soil and water conservation where seeing is believing.52 Although farmers can financially contribute to costs, public funding is required to prepare, facilitate, and follow up such visits.

Tackling food security and poverty in Africa requires a determined effort to maintain momentum in research, optimize promising technologies, and validate all promising ones on-farm to provide visibility and demonstrate practicability. Long-term research is an ongoing process that should be adequately funded to keep abreast of developments in science and social dynamics that science must endeavor to satisfy. Endogenous knowledge and innovation should be nurtured rather than totally abandoned for some discarded and inappropriate foreign technologies. Finally, there must be active exchange of experiences and ideas that can be facilitated by proper documentation of data and information.

To support all the actions needed to improve agricultural productivity in Africa, agricultural research systems need significantly higher levels of funding. Also, forging strategic alliances at national and regional levels and new public–private partnerships is essential. In this regard, it is important to strengthen national, subregional, and international agricultural research bodies in the region. Consortia of research and development institutions can also supplement national extension efforts to scale up effects. An example of such a consortium is COSOFAP (Consortium for Scaling Up Options for Improving Farm Productivity), which at one time had more than 60 partner organizations and reached out to thousands of farmers in 22 districts in western Kenya.39 It has also catalyzed formation of similar consortia in the Lake Victoria Zone districts of Uganda and Tanzania. Success factors for scaling up effects include maintaining a stream of innovations developed in a participatory manner with farmers, local nongovernmental organization (NGO) involvement in developing and testing innovations, and a small secretariat with some reasonable financing to share and communicate often with network members.

Improving Weather Forecasts

Because most of the agriculture in the region is rain fed, there is need for better prediction of short-, medium-, and long-term weather conditions at both national and regional levels. There are many uncertainties that farmers face with respect to the unpredictability of weather in Africa, including when and what to plant. There is mounting scientific evidence indicating that if current climate trends continue, drier areas will become drier and droughts more frequent,54,55 and wetter areas will become more flooded. Improving weather predictions requires strengthening the surveillance ability of regional and national weather programs and fostering greater collaboration between states in the region and beyond. Because water and food security are intertwined, there is also great need to improve hydrological data monitoring, collection, and dissemination systems at national and regional levels. A complementary point to consider is the possibility of having massively available weather-related insurance programs for smallholder farmers—to help them deal with droughts, floods, and breakout of pests and diseases.

Improving Market Access

There is, indeed, considerable potential for Africa to increase agricultural growth and alleviate hunger and poverty through market-led processes. Contrary to the pessimism expressed in some quarters, adequate market opportunities exist that have yet to be fully exploited and that could support more rapid and sustained agricultural growth in Africa. For instance, staple foods represent a promising domestic market opportunity, particularly because Africa is not only a net importer of many staple foods but also because projections show that continent-wide demand for human consumption and livestock feed will double by 2015, adding another $50 billion per year to effective demand.56 Many African farmers are well positioned to compete in these staple markets. Moreover, growing urban markets in Africa are increasing the demand for more diverse and higher value-added foods, thereby offering new opportunities for many African farmers.

Many African countries also possess a comparative advantage in those commodities imported by other African countries. By reducing their trade barriers in both the agricultural and nonagricultural sectors, African countries can increase intraregional agricultural trade by more than 50%.57 Intra-African trade can also increase food security by facilitating the transfer of production from high-potential agroecological zones to areas with structural food deficits. Because cross-border exports may not be subject to the same level of stringent quality standards required for international markets, intra-African trade might be more accessible to smallholders.58 Greater cross-border trade in food staples could also help stabilize food supplies and prices at subregional levels in drought years.

With the increasing market instability and competition for smallholders, a critical issue is the farmers' competitiveness and ability to improve their market position. One way to enhance such productivity is by taking advantage of economies of scale. Collective marketing through rural producers' organizations can be one effective way to overcome constraints faced by small-scale farmers, including lack of capital, imperfect information, geographic dispersion, and poor infrastructure and communications.59 These constraints are exacerbated by the withdrawal of the state from productive activities, concurrent with a still underdeveloped private sector. Acting collectively through farmers' associations, farmers can mitigate transaction costs and therefore accrue benefits from collective marketing. This is, indeed, a key factor behind the success of smallholder tea, coffee, and dairy farmers in the highlands of Kenya.27

Contract farming is another mechanism for improving market access that perhaps can take over the roles previously served by the state in providing information, inputs, and credit. A key question is the extent to which contract farming can serve the small farmers who are the targets of poverty reduction programs. In general, the evidence thus far suggests that nearly all contract farming schemes exclude small farmers.60 Many of the transaction costs that keep firms away from contracting with smaller growers result from weak institutions. For example, if markets for information were better developed, growers might directly access important production information rather than relying on the firm for the high fixed costs of extension services. There are many success stories in Africa that can provide insights for developing this mechanism further. Examples include the smallholder tea farmers in Malawi,61 the dairy farmers in Kenya,7 and the confectionary peanut growers in Senegal.62,63

How should smallholders respond to changes in agrifood organizations, such as the rise of supermarkets throughout the world? One obvious answer is to treat these changes as a commercial reality and to organize to engage with this reality. In concrete terms, this means forging direct relations with new markets, as well as with information providers, NGOs, private actors, and the state. The logic of engagement with new markets means that small farmers must build a new generation of economic organizations that perform at higher levels of specificity, coordinate technology, and improve scheduling. Transfer of knowledge from other regions, such as Asia and Latin America, where these linkages are more advanced, is important. However, reducing the exorbitant marketing margins created by transportation and transaction expenses must first be addressed. Reducing these margins involves improvements in road and transportation networks; increased access to market information systems; and enhanced coordination and contractual arrangements among farmers, traders, and buyers. An added advantage is that these investments in rural infrastructure and market development would facilitate links with the nonfarm sector, stimulating overall income and employment in both rural and urban areas and leading to more demand for agricultural products.

Defining an appropriate and feasible role for the public sector in the postreform era is critical for success. Because the demand for agricultural goods is generally highly inelastic, and particularly so in the presence of market failure, even small increases in aggregate production can dramatically decrease output prices. Thus, increased production achieved through technology adoption can have serious negative consequences for smallholders' incomes through the decline of output prices. Ultimately, the decline in prices renders it inviable for producers to continue adopting technology, undermining the future growth of production. Countries that have succeeded in overcoming this problem and achieving dramatic increases in productivity, as for the Green Revolution in Asia, have done so through an integrated approach that encourages the continued adoption of technology while addressing ways of making demand more price responsive. This approach improved the efficiency of domestic markets, generating demand through expanded export trade and developing agroindustrial linkages. This integrated approach may also comprise efforts to stabilize prices in the short term through direct public intervention, including the use of guaranteed floor prices. Without such a concerted strategy, as Cochrane64 put it, “technological advance sows the seeds of slow-down” (p. 100).

Improving Credit Systems

The current agricultural credit landscape is characterized by a variety of small-scale, donor-funded NGO efforts to build farmer associations that can access private sources of input credit, interlinking market arrangements for export crops in various stages of transformation from prereform parastatals to postreform competitive markets and government-run input credit programs. The provision of credit at reasonable interest rates is viewed as particularly critical because investments in fertilizers, improved seeds, and small-scale water management will usually be profitable, despite the poor marketing conditions of most rural areas.20,28 Community banks, such as the Grameen Bank model of Bangladesh, can be a basis for innovation. The bank targets small loans to groups of virtually all-female producers.65 Whether this approach can be replicated in Africa has received little attention, with the possible exception of the Sasakawa 2000 program in Benin, which mobilizes savings before loaning to farmers.66

Revisiting Input Support Programs

Nearly all the essential interventions mentioned require public investment for them to happen at the scale desired. However, special support needs to go into provision of fertilizers and, to some extent, improved seeds. With the high cost of fertilizers and the precarious food security situation of Africa, it is doubtful whether credit programs alone would result in the levels of investments needed to increase productivity. There is, indeed, need for public support and investment—at least to jump-start smallholder production. It is in this regard that many governments are now revisiting input subsidies. There are many arguments against subsidy programs that led to their removal and the introduction of the structural adjustment programs of the 1980s.67 A common argument by economists is that because not all outputs can be equally subsidized, output price increases will have greater effect than will input subsidies, especially in the long run.68

This line of reasoning makes sense when applied to Asia and Latin America now, but it did not make sense during their Green Revolution era in the 1960s and 1970s, when fertilizer use contributed 50%–75% of the increase in yields in food crops69 and adoption of modern varieties of fertilizer depended on fertilizer subsidies.6,70 Neither does it apply to current conditions in Africa, where average fertilizer use—not nutrient use—is a mere 7–11 kg/ha. African governments have committed to increase fertilizer use levels to at least 50 kg/ha.71 Near-term environmental concerns in African agriculture stem more from the persistent decline of soil fertility than from overuse of fertilizers, because this leaves continuous expansion of cultivation to relatively unused areas as the only option for increasing total output. Policy interventions are thus needed to encourage smallholder farmers to increase the yields of their traditional crops, as well as modern varieties, and fertilizer subsidies in the form of vouchers are the most direct policy tool that planners have at their disposal.72

It is for these reasons that many countries in Africa are now reintroducing fertilizer subsidies and redesigning them in ways that promote private-sector engagement through voucher systems that can be redeemed at private agrodealers. Malawi is a recent example of a country where the government has spearheaded public subsidies for inputs, and the effect on increasing production and food security has been remarkable.73

Fertilizer subsidies can decrease the many risks that resource-poor farmers have and therefore can play an important role in increasing their food production.72 Therefore, the donor community has been blamed for failing to present a balanced view6 of the substantial role that subsidies played (and still play) in Asia's Green Revolution. Indeed, fertilizer subsidies could serve as a temporary measure to compensate for the factors that make it difficult for African, as opposed to Asian, entrepreneurs to freely compete in an open fertilizer market.74 But fertilizer prices can perhaps be brought down only if, in the long run, governments invest in infrastructure to reduce transportation and marketing costs. Until then, there is a strong case for fertilizer subsidies to compensate for the factors resulting in the high fertilizer prices.

It Can Be Done: Emerging Evidence

  1. Top of page
  2. Abstract
  3. Introduction
  4. Key Constraints to Increasing Production
  5. Approaches to Soil Fertility Improvement
  6. Other Complementary Interventions
  7. It Can Be Done: Emerging Evidence
  8. Conclusion
  9. Acknowledgments
  10. Conflicts of Interest
  11. References

There is now a global consensus75 that turning African agriculture around requires the following seven actions working together:

  • 1
    increasing the agricultural production of food-insecure farmers,
  • 2
    improving access to markets and income generation,
  • 3
    restoring degraded ecosystems,
  • 4
    promoting political commitment and action at global levels,
  • 5
    enabling policy reforms in the African countries,
  • 6
    empowering communities in hunger hotspot areas, and
  • 7
    improving nutrition with productive safety nets.

The seventh action, although not discussed in great detail here, is essential for many rural households that are landless or nearly so. It is also one way to assist many homes ravaged by the HIV/AIDS pandemic. Food aid is one intervention to achieve this objective, and procurement of locally grown foods can have the added advantage of creating markets for farmers.11 Other key ingredients for success include self-sufficiency in food grain, an enabling geopolitical environment and domestic factors, the application of science and technology, state interventions in agriculture that are focused on small farmers, and market mediation.

These, indeed, are the aims of the poverty reduction strategies that most countries in Africa are currently developing and that aim at achieving the Millennium Development Goals by 2015.75 The Millennium Villages Project40 is clearly demonstrating the effects of putting the recommendations of the United Nations Millennium Project into action. Key principles of the villages include the use of proven science and technology and strong community participation in planning and implementation. The project has 12 village-level programs in 10 countries, covering a population of about 120 people. The locations of the villages are selected to represent the key farming systems of Africa. Some of the effects observed include quadrupling of maize yields with provision of fertilizer and improved seeds by the project in villages in maize-based farming systems of Kenya and Malawi.40 In some of the villages, farmers also increased area production, all from fields that had been abandoned because of low soil fertility and related weed infestation. The school feeding program has begun, with farmers giving back 10% of their harvest to the school. School attendance (especially by girls) and performance has increased tremendously. In the first village to be established, exit strategies for the input subsidies (fertilizer and seeds) started in year 3, starting with the relatively wealthier households (US$2.60 per day).40 Farmers purchased their own inputs or obtained loans from a microfinance provider.

Investments in villages have also been made in health, water and sanitation, roads, energy, and environment. This is happening at investments of about US$110 per person per year. This investment is shared by partners as follows: US$10 in kind by the community (through their labor that is used for, e.g., the constructions of schools, health clinics, and protecting water points); US$30 by the national and local government (including cash and in-kind contribution, e.g., provision of teachers and secondment of nurses to the community health center); US$20 by NGO- and other donor-funded funded projects operating in the area; and US$50 per capita by the Millennium Villages Project. Over time, these costs will be assumed by the farmers through interventions that diversify their production base, enterprise, and skill development, especially in marketing.

Scaling up and sustaining the village-level success to national levels is the ultimate goal of all governments and their development partners. Malawi, for instance, initiated in 2005 a universal fertilizer subsidy program of its own. The combined effect of fertilizers, improved seeds, and good rains resulted in bumper harvests. A repeat of the same in 2006 saw the country go from one of food deficit to one with surplus, thus eliminating food imports.40,73 Some partners in the donor community supported it on the basis that fertilizer is critical to boosting production and assuring food security and that phasing out over time once farmers had built up their ability and asset base was the best option. Others that opposed it initially are now supporting the government in designing the program in ways that enhance private-sector participation in the delivery of inputs.

The Malawi case is, indeed, a success story that several other countries in Africa are now emulating. It demonstrates that the Green Revolution can, indeed, happen in Africa. Through the “smart” voucher system, the program is being modified to support the growth of the private sector. In general, weak engagement of the private sector is seen as a major limitation of government-run subsidy programs.76

Conclusion

  1. Top of page
  2. Abstract
  3. Introduction
  4. Key Constraints to Increasing Production
  5. Approaches to Soil Fertility Improvement
  6. Other Complementary Interventions
  7. It Can Be Done: Emerging Evidence
  8. Conclusion
  9. Acknowledgments
  10. Conflicts of Interest
  11. References

The effects of declining agricultural productivity in Africa, the region where this decline is most acutely observed, will exacerbate poverty—in particular through its effects on both rural and urban food supplies. Equally, underperforming agriculture makes economic growth difficult and can have negative environmental consequences. This chapter has highlighted some of the specific constraints that Africa's smallholder agriculture faces—including declining soil fertility, limited use of improved germplasm, dependence on unreliable rainfall, poor extension services to farmers, and poor access to markets. The technologies and innovations needed to address these problems exist already on the continent. The challenge is to help farmers access them and to do so at scale. This goal is essential for the achievement of the African Green Revolution whose call is now out and certainly overdue. African governments and leaders have stepped up effort and are finding solutions to old problems, including the provision of targeted input subsidies.

The effects on food security can be rapid, as demonstrated by Malawi's input subsidy program and by the Millennium Villages Project. These effects need to be scaled up and governments supported to build the technical and institutional capacity to sustain it. An important challenge and priority for future research will be to identify the type and scale of public–private partnerships needed for developing comprehensive and sustainable input and output markets. To this end, cross-country collaboration among developing nations can add tremendous value to this process, especially in the transfer of technologies and development of market skills.

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  3. Introduction
  4. Key Constraints to Increasing Production
  5. Approaches to Soil Fertility Improvement
  6. Other Complementary Interventions
  7. It Can Be Done: Emerging Evidence
  8. Conclusion
  9. Acknowledgments
  10. Conflicts of Interest
  11. References
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