Key Findings from the MA Scenarios
In all four scenarios, desertified area is likely to increase, though at different rates. Poverty and unsustainable land use practices continue to be the main factors driving desertification in the near future. The relief of pressures on drylands is strongly correlated with poverty reduction. Under all four MA scenarios, population growth and increase in food demand will drive an expansion of cultivated land, often at the expense of woodlands and rangelands. This is likely to increase the spatial extent of desertified land. No scenario indicates a reversal in the threat of desertification (S9, S8 Figure 8.5). (See Figure 4.1.)
In all the scenarios, climate change is linked to desertification, and the impacts of climate change vary according to region and the management approach adopted. Climate change is expected to affect the global hydrological cycle and local precipitation trends. The local manifestation of these global climate changes is strongly location-dependent. It is likely that extreme events will further intensify, bringing more ﬂoods and more droughts (S8 Figure 8.5, S14.4.4).
Coping with desertification and related economic conditions in drylands will likely fare better in a future where proactive management approaches are used. In a proactive approach, ecosystem management is aiming to be adaptive to changes and to make ecosystems more resilient, which is seen as also reducing the vulnerability of society to the disturbances caused by desertification. As a result, measures such as adaptations to climate change and non-expanding irrigation can jointly lead to decelerated desertification rates. This approach might take some time to show its benefits, however, as the necessary changes in development and learning capacities first need to be further developed and improved. In contrast, under a reactive management regime, current pressures (climate change, overgrazing, and large-scale irrigation) on ecosystem services are likely to stay the same or intensify, leading to further desertification. The regionalized-reactive scenario demonstrates the greatest unsustainability of dryland development (S.SDM).
Globalization will not necessarily lead to increased desertification. Prospects for cooperation and resource transfers to support ecosystem management are better in this case due to the institutional reforms and the fast rate of technological development. In the globally proactive management scenario, policy reforms such as strengthening of property rights (either private or collective) as well as better integration of environmental issues lead to relatively less pressure in drylands. Market and policy failures can still pose risks of desertification, however. In contrast, in a fragmented world, the role of a global agreement is more limited either because of the diminished interest in resource transfers or because of the lack of interest beyond the national or regional boundaries (S14.ES, S14.4.3).