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Keywords:

  • biodiversity conservation;
  • climate change;
  • ecological networks;
  • ecosystem services;
  • landscape management;
  • range shift

Summary

  1. Top of page
  2. Summary
  3. Introduction
  4. Understanding the impact of climate change on species
  5. Understanding the value of what we have to better face change
  6. Where to from here?
  7. References

1. Climate change is a major threat to biodiversity, ecosystem services, and human well-being. Mitigating its effects on living organisms and societies will be at the heart of most environmental management strategies, which will need to be informed by integrative scientific approaches. This Issue’s Special Profile provides examples of such approaches.

2. Responses of species to change in climatic conditions will range from thriving (i.e. species capable of living under the new set of conditions) to adapting (i.e. species capable of surviving a change in global conditions by changing their ecology and/or distribution) and going extinct. Yet there is a need to identify which species will fall into which categories, as well as a need to understand how to facilitate species’ ability to adapt to change.

3. Landscape management will be key to ensuring that functional, resilient ecosystems are maintained. Preserving the complexity and function of ecosystems can help mitigate the impact of extreme climatic conditions on the delivery of vital services such as climate regulation, primary production and water retention.

4. To mitigate further biodiversity loss, healthy habitats will also need to be better connected. In many situations, developing ecological networks will require costly habitat restoration at large spatial scales: to maximise opportunities for these networks to be created and be successful, landscape-scale assessments of the provision and value of multiple ecosystem services under alternative management regimes will need to inform decisions as to where and how to implement their creation.

5.Synthesis and applications. Climate change is only starting to shape the ecological research agenda, as the complexity of the impact of this phenomenon on biodiversity and ecosystem services slowly unveils. Because changes in climatic conditions are expected to hit everyone everywhere, effective solutions for climate change mitigation will require science to truly engage with society and support decision-making processes at local, national and international scales.


Introduction

  1. Top of page
  2. Summary
  3. Introduction
  4. Understanding the impact of climate change on species
  5. Understanding the value of what we have to better face change
  6. Where to from here?
  7. References

Who hasn’t heard about or does not have an opinion on climate change? Highly debated, holding its own section in various newspapers, taught in schools, climate change is a phenomenon that has managed to grab the attention of societies around the world. Such a level of global agitation is understandable: climate change is expected to hit everyone, directly or indirectly, and there is currently no easy way out. Climate change cannot be fixed by a quick cash injection or a simple change in individual behaviour: to minimise the impact of projected changes in climatic conditions on living organisms, including us, necessitates, among other things, a fast and profound transformation in how we all do things; how we consume; and how we, as nations, develop (Planet Under Pressure 2012).

But what exactly should we do? Admittedly, the first step is to dramatically reduce greenhouse gas emissions to safe levels. But even if this was to happen tomorrow, greenhouse gases already emitted since the industrial revolution have committed us to a temperature rise of a degree or more (IPCC 2007). These emissions have indeed been significant enough to induce changes in average temperature and precipitation, changes in seasonal patterns and changes in the frequency of extreme weather events (IPCC 2007, 2012). These changes have not occurred unnoticed, with several studies reporting a range of responses from a wide array of species to reported changes in climatic patterns (Walther et al. 2002; Parmesan 2006; Lenoir et al. 2008), including latitudinal and altitudinal distribution range shifts; reduced survival and/or reproduction; and increased extinction risk (Thomas et al. 2004). Said differently: current levels of greenhouse gas concentrations are already having an impact on biological diversity. Can we afford further biodiversity loss from climate change? With biodiversity continuing to disappear at fast rates (Butchart et al. 2010), and biological diversity suspected to underpin the functioning of the ecosystems on which we depend for food and fresh water, health and recreation, and protection from natural disasters (Millennium Ecosystem Assessment 2005), the answer is ‘not really’.

So what should we do to reduce the probability that current and future changes in climatic conditions lead to increasing rate of biodiversity loss, decreasing ecosystem functions and health, and reduced supply of ecosystem services? As applied ecologists aware of the number of actors, processes, scales, interactions and desirable outcomes at play, we definitively need to embrace the discussions around this question and be more heavily engaged in decision-making. There are many opportunities for science to inform strategies to help reduce the impact of climate change on biodiversity and ecosystem services while broadening our understanding of ecological systems. This Issue’s Special Profile, entitled ‘Adapting conservation to a changing climate’, provides examples of such opportunities.

Understanding the impact of climate change on species

  1. Top of page
  2. Summary
  3. Introduction
  4. Understanding the impact of climate change on species
  5. Understanding the value of what we have to better face change
  6. Where to from here?
  7. References

A first set of opportunities for science to inform environmental management in the face of climate change is linked to increasing our understanding of how changes in climatic conditions will impact species. Climate change is generally perceived as a synonym of global warming, yet an increased average temperature on earth is not the only expected consequence of climate change: changes in rainfall and temperature seasonal patterns, changes in the frequency of extreme events and changes in greenhouse gas concentrations are also to be expected (IPCC 2007, 2012), and all of these pose a direct or indirect threat to species’ survival globally. Responses of species to such changes can be expected to fall into one of the following three categories: (i) thrive (i.e. the species is capable of living under the new set of environmental conditions), (ii) adapt (i.e. the species is capable of changing its ecology and/or distribution to avoid extinction), (iii) go extinct (i.e. the species will slowly decline and eventually be lost). There is a need to identify which species will fall into which categories, as well as to understand how to facilitate species’ ability to adapt to change.

Species distribution models (SDMs) have been extensively used to explore the impact of climate change on species distribution and extinction risk (Dawson et al. 2011; Bellard et al. 2012), allowing predictions to be made about which species might thrive, or be at risk of extinction. Little is known, however, about the ability of SDMs to provide relevant information about spatial variation in the probability of long-term population persistence. This is important because if high habitat suitability is not correlated with high probability of long-term population persistence, then global assessments of species’ vulnerability to climate change exclusively based on SDMs might underestimate the proportion of species at risk. In the first article in this Special Profile, Oliver et al. (2012) explore how SDMs can be used to predict areas where populations will have the highest densities and most stable population dynamics under changing climatic conditions. Using data for 20 bird and butterfly species across 1941 sites in the United Kingdom over 15 years, they show that SDMs may be appropriate for predicting spatial variation in population density but not stability. Population density is an important parameter of persistence in the face of demographic and environmental stochasticity: provided that the results reported in this study hold for other taxa, SDMs might be part of the toolkit needed to identify those populations likely to act as species’ strongholds.

For those species that clearly need to change their distribution to avoid extinction, there is then an urgent need to understand how their range shifts can be facilitated. Previous studies have highlighted the importance of increasing landscape-scale connectivity through, for example increased habitat aggregation, corridor creation or improved matrix permeability to support colonisation (Manning, Gibbons & Lindenmayer 2009; Krosby et al. 2010), but few have explored the pertinence of other, complementary management approaches. In a second article from this Special Profile, Lawson et al. (2012) investigate the local and landscape determinants of colonisation in the silver-spotted skipper butterfly Hesperia comma, using data from 724 habitat patches over a 9-year period. Using this example, they demonstrate how enhancing population survival at leading range edges can help facilitate colonisation and range shifts. Although climate change and the associated loss of biodiversity and ecosystem services are global phenomena, effective mitigation strategies are likely to be set locally: knowing where to act as a priority and what to do are among the key questions that will need to be answered, and to do so requires permanent dialogue between scientists and local managers.

Understanding the value of what we have to better face change

  1. Top of page
  2. Summary
  3. Introduction
  4. Understanding the impact of climate change on species
  5. Understanding the value of what we have to better face change
  6. Where to from here?
  7. References

Pressures on the environment are multiple, and climate change is only one of the challenges associated with biodiversity loss mitigation and the preservation of ecosystem services. Last October, for example, the world population was estimated to have reached over seven billion people (United Nations 2011): to feed this expanding human population, it has been anticipated that by 2030, crop production must increase by 43% and meat production by 124% (Food and Agriculture Organisation 2009; Gordon et al. 2012). Increasing food demand can be expected to lead to more land being converted for agriculture, which means that conservation and food security agendas will need to be integrated. In the face of climate change, discussions about what we can afford to lose and what we should preserve thus need to occur. This open dialogue about the trade-offs that will need to be considered to retain the global benefits of biodiversity is important, as transparency can be expected to lead to more democratic decision-making, an increased sense of community and social justice, and respect for indigenous, rural and local ways of life, all of which are known to be hallmarks of successful management approaches.

To inform these discussions, a good understanding of how various landscapes can support climate change adaptation is essential. In a third article from this Special Profile, Norris, Hobson & Ibisch (2012) test the hypothesis that more mature ecosystems have lower surface temperatures and are therefore associated with a higher capacity to aid in mitigating the effects of extreme temperatures. Using thermodynamic theory, the authors demonstrate how old-growth woodlands in the United Kingdom, Germany and Ukraine are able to attenuate surface temperature more effectively than native species plantations. In this part of the world, climate change is expected to lead to heat waves and droughts becoming more common and more intense (IPCC 2012): more studies such as these are needed to guide environmental management decisions, before natural shields against climate change are lost for good.

Because funding is limited, and because management actions can be costly, these discussions will also require stakeholders to be able to balance the benefits of any given management decision with its associated costs. The fourth contribution to this Special Profile by Newton et al. (2012) provides an example of how this can be achieved, using ecological networks as a case study. The authors focus on the catchment of the River Frome in Dorset, England, where they examined the potential impact of large-scale habitat restoration on the value of multiple ecosystem services. They show that, although restoration scenarios were associated with increased provision of multiple ecosystem services, their costs always exceeded the market value of the ecosystem services delivered. These results emphasise that (i) economic assessments will not always favour conservation, (ii) how society economically values benefits derived from ecosystem is, in the end, what drives economically based decisions to support conservation. They also add a twist to recent reports on the growing costs of biodiversity loss and ecosystem degradation by initiatives such as ‘The Economics of Ecosystems and Biodiversity’ (TEEB): it is one thing to value how much money is saved by preserving a healthy ecosystem; it is another to value how much money could be gained by transforming a degraded ecosystem into a healthier one, as these two sets of information are not systematically correlated. Ultimately, transparent cost-benefit analyses such as the one presented by Newton et al. are crucially needed to support decision-making, as failures to explicitly acknowledge the costs and conflicts associated with the preservation of biodiversity and ecosystem services can represent a major obstacle to reaching such aims.

Where to from here?

  1. Top of page
  2. Summary
  3. Introduction
  4. Understanding the impact of climate change on species
  5. Understanding the value of what we have to better face change
  6. Where to from here?
  7. References

Climate change is only starting to shape the ecological research agenda, as the complexity of its impact on biodiversity and ecosystem services slowly unveils. Research is needed to understand how climate change interacts with other threats (e.g. habitat loss, habitat fragmentation, poaching, disease, invasive species) to increase species’ vulnerability to global environmental change (Dawson et al. 2011; Ameca y Juarez et al. 2012). Integrative approaches relating species and populations are urgently needed to improve the efficiency of conservation efforts (Ceballos, García & Ehrlich 2010): SDMs need to be combined with spatially explicit models of changes in threat distribution and intensity to identify those populations most likely to act as strongholds for the species, so that management actions can be strategically targeted. Although studies have started investigating the problem for plants (see e.g. Jump & Peňuelas 2005), little is known of the true potential of species to tolerate or adapt to climate change: because of this, management options (e.g. assisted colonisation vs. in situ management options) are difficult to weight.

Most national or regional biodiversity conservation strategies are linked to the creation and maintenance of protected areas, yet the static nature of this network means that conservation efforts could be wasted with climate change. Protected areas at risk need to be identified, while stakeholders need to be provided with the necessary information required to prioritise new areas for conservation. Landscape-scale connectivity among preserved patches will help to buffer ecosystems against changes in climatic conditions: approaches acknowledging the costs and benefits of various possible matrices will be required, so that consensus can be reached. Cost-benefit analyses have to be informed by a clear understanding of the nature and value of ecosystem services at play: such an understanding can only be reached by opening strong lines of communication between science and the general public. Science will also be needed to inform the integration of multiple environmental agendas, such as conservation and food security agendas (Gordon et al. 2012). As pointed out by the fifth contribution to this Special Profile, a better ability to define and measure ecosystem resilience, as well as an increased understanding of the factors shaping this parameter will moreover be required to support efforts to forecast the impact of climate change on the delivery of ecosystem services (Morecroft et al. 2012).

Multidisciplinary approaches that involve ecologists, social scientists, economists and political scientists as well as businesses from the outset can only help in the design of broadly accepted, and therefore effective, conservation measures: because platforms and facilities to support such initiatives are still scarce, these approaches are too rare. International interfaces do exist: for example, the emerging Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) is a clear initiative to provide a bridge between scientific knowledge and policy (Perrings et al. 2011). Likewise, programmes such as the ‘Ecosystems Services and Poverty Alleviation’ (ESPA) and the ‘Living with Environmental Change’ (LWEC) from the Natural Environment Research Council in the United Kingdom are examples of programmes designed to help foster collaboration among scientists with diverse expertise. These opportunities, however, are mostly beneficial to already well-connected organisations, interest groups or individuals: grass-root approaches that bring together stakeholders who have little previous knowledge of each other are still missing. Likewise, platforms supporting the direct communication between local managers in need of support and scientists are virtually non-existent, and their potential importance undervalued. Many scientists want to help and do not know how to proceed; many managers need help and do not know who to ask. Finally, and perhaps most importantly, research institutions and funding agencies need to commit to applied science the way they commit to theoretical science: ‘impact’ is a category that is starting to appear in grant proposals; now that it has appeared, it needs to matter.

References

  1. Top of page
  2. Summary
  3. Introduction
  4. Understanding the impact of climate change on species
  5. Understanding the value of what we have to better face change
  6. Where to from here?
  7. References
  • Ameca y Juarez, E.I., Mace, G., Cowlishaw, G. & Pettorelli, N. (2012) Natural population die-offs: causes and consequences for terrestrial mammals. Trends in Ecology and Evolution, doi: 10.1016/j.tree.2011.11.005.
  • Bellard, C., Bertelsmeier, C., Leadley, P., Thuiller, W. & Courchamp, F. (2012) Impacts of climate change on the future of biodiversity. Ecology Letters, 15, 365377.
  • Butchart, S.H.M., Walpole, M., Collen, B., van Strien, A., Scharleman, J.P.W., Almond, R.E.A., Baillie, J.E.M., Bomhard, B., Brown, C., Bruno, J., Carpenter, K.E., Carr, G.M., Chanson, J., Chenery, A., Csirke, J., Davidson, N.C., Dentener, F., Foster, M., Galli, A., Galloway, J.N., Genovesi, P., Gregory, R., Hockings, M., Kapos, V., Lamarque, J.-F., Leverington, F., Loh, J., McGeoch, M.A., McRae, L., Minasyan, A., Hernández Morcillo, M., Oldfield, T., Pauly, D., Quader, S., Revenga, C., Sauer, J., Skolnik, B., Spear, D., Stanwell-Smith, D., Stuart, S.N., Symes, A., Tierney, M., Tyrrell, T.R., Vié, J.-C. & Watson, R. (2010) Global biodiversity decline continues. Science, 328, 11641168.
  • Ceballos, G., García, A. & Ehrlich, P.R. (2010) The sixth extinction crisis loss of animal populations and species. Journal of Cosmology, 8, 18211831.
  • Dawson, T.P., Jackson, S.T., House, J.I., Prentice, I.C. & Mace, G.M. (2011) Beyond predictions: biodiversity conservation in a changing climate. Science, 332, 5358.
  • Food and Agriculture Organisation. (2009) The State of Food and Agriculture 2009: Livestock in the Balance. FAO, Rome, Italy.
  • Gordon, I., Acevedo-Whitehouse, K., Altwegg, R., Garner, T., Gompper, M., Katzner, T., Pettorelli, N. & Redpath, S. (2012) What the “food security” agenda means for animal conservation in terrestrial ecosystems. Animal Conservation, 15, 115116.
  • Intergovernmental Panel on Climate Change – IPCC. (2007) Climate change 2007: synthesis report. Fourth Assessment Report of the Intergovernmental Panel on Climate Change.
  • Intergovernmental Panel on Climate Change – IPCC. (2012) Summary for policymakers. Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (eds C.B. Field, V. Barros, T.F. Stocker, D. Qin, D.J. Dokken, K.L. Ebi, M.D. Mastrandrea, K.J. Mach, G.-K. Plattner, S.K. Allen, M. Tignor & P.M. Midgley), pp. 119. A Special Report of Working Groups I and II of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK, and New York, NY, USA.
  • Jump, A.S. & Peňuelas, J. (2005) Running to a standstill: adaptation and the response of plants to rapid climate change. Ecology Letters, 8, 10101020.
  • Krosby, M., Tewksbury, J., Haddad, N.M. & Hoekstra, J. (2010) Ecological connectivity for a changing climate. Conservation Biology, 24, 16861689.
  • Lawson, C.R., Bennie, J.J., Thomas, C.D., Hodgson, J.A. & Wilson, R.J. (2012) Local and landscape management of an expanding range margin under climate change. Journal of Applied Ecology, 49, 552561.
  • Lenoir, J., Gegout, J.C., Marquet, P.A., de Ruffray, P. & Brisse, H. (2008) A significant upward shift in plant species optimum elevation during the 20th century. Science, 320, 17681771.
  • Manning, A.D., Gibbons, P. & Lindenmayer, D.B. (2009) Scattered trees: a complementary strategy for facilitating adaptive responses to climate change in modified landscapes? Journal of Applied Ecology, 46, 915919.
  • Millennium Ecosystem Assessment. (2005) Millennium Ecosystem Assessment Synthesis Report. Island Press, Washington D.C., USA.
  • Morecroft, M., Crick, H., Duffield, S. & MacGregor, N. (2012) Resilience to climate change: translating principles into practice. Journal of Applied Ecology, 49, 547551.
  • Newton, A., Hodder, K., Cantarello, E., Perrella, L., Birch, J., Robins, J., Douglas, S., Moody, C. & Cordingley, J. (2012) Cost-benefit analysis of ecological networks assessed through spatial analysis of ecosystem services. Journal of Applied Ecology, 49, 571580.
  • Norris, C., Hobson, P. & Ibisch, P.L. (2012) Microclimate and vegetation function as indicators of forest thermodynamic efficiency. Journal of Applied Ecology, 49, 562570.
  • Oliver, T., Gillings, S., Girardello, M., Rapacciuolo, G., Brereton, T., Siriwardena, G., Roy, D., Pywell, R. & Fuller, R. (2012) Population density but not stability can be predicted from species distribution models. Journal of Applied Ecology, 49, 581590.
  • Parmesan, C. (2006) Ecological and evolutionary responses to recent climate change. Annual Review of Ecology Evolution and Systematics, 37, 637669.
  • Perrings, C., Duraiappah, A., Larigauderie, A. & Mooney, H. (2011) The biodiversity and ecosystem services science-policy interface. Science, 331, 11391140.
  • Planet Under Pressure. (2012) State of the Planet Declaration. March 26–29, Planet Under Pressure, London, UK.
  • Thomas, C.D., Cameron, A., Green, R.E., Bakkenes, M., Beamont, L.J., Collingham, Y.C. et al. (2004) Extinction risk from climate change. Nature, 427, 145148.
  • United Nations, Department of Economic and Social Affairs, Population Division. (2011) World population prospects: the 2010 revision, highlights and advance tables. ESA/P/WP.220.
  • Walther, G.R., Post, E., Crsonvey, P., Menzel, A., Parmesan, C., Beebee, T.J.C., Fromentin, J.M., Hoegh-Guldberg, O. & Bairlein, F. (2002) Ecological responses to recent climate change. Nature, 416, 389395.