Increasing the Resilience of Dryland Agro-Ecosystems to Climate Change

Introduction The current debate on climate change, its impacts on socio-ecological systems and the role of agriculture has shifted from an emphasis on how to mitigate the effects of increasing greenhouse gas (GHG) emissions to how to prepare and adapt to the expected adverse impacts. This follows the recognition that the climate is already changing as a result of mankind’s activities and there is little that can be done to prevent further increases in atmospheric concentrations of GHG in the short term (Henson, 2006). There is much debate on what are the likely tipping points where irreversible changes will occur in the earth’s ecosystems (Schellnhuber et al., 2006; Stern 2007). In addition the linkages between climate change, land degradation and loss of biodiversity are increasingly viewed as highly interactive, requiring more holistic frameworks and approaches in order to solve common problems (MEA, 2005). These converging viewpoints lead to an increased focus on sustainable land management and development whereby incomes of the poor can be increased but not at the expense of the natural resource base and the environmental services they provide. A recent scientific workshop distilled the problem of sustainable land management down to a need to maintain a protective biological surface cover (living plants or mulches), good soil structure to allow gas, water and nutrient exchanges between soils and plants and adequate levels of soil organic matter and their soil-inhabiting organisms (TAA, 2007). These measures would also reduce the GHG emissions associated with food production This biophysical perspective needs to be combined with a socio-ecological perspective whereby the driving forces behind land use decision making are clearly understood in terms of the socio-economic context and the asset base of the land users (i.e. the use of the sustainable livelihood perspective and the principles of physical, human, social, financial and natural capitals (Bebbington, 1999). Sustainable land management includes the utilisation and conservation of