Rural communities in drylands are often poorer than elsewhere and the land is more vulnerable to degradation from climate change and direct human pressures. Poor management can lead to desertification. We know how to manage drylands sustainably, but often do not achieve this in practice; policies and agricultural systems need to be transformed if we are to avoid the continued loss of health and productivity in the drylands.
Chapter 12: Drylands
Drylands cover 41 per cent of the land surface, produce 44 per cent of the crops, and contain over 2 billion people and half of the world’s livestock. Drylands include some of the most productive areas on the planet, but also some of the most fragile, where minor alterations in conditions can result in dramatic changes in ecology and subsequently in human well-being. Today, drylands face increasingly acute threats from the over-use of resources, poor management, and a changing climate.
Dryland degradation costs developing countries an estimated 4-8 per cent of their national domestic product each year (UN Environmental Management Group, 2015, Box 12). Understanding drylands is critical to achieving their long-term sustainable management. Some key biophysical and social characteristics of dryland landscapes are summarized in this chapter, including:
- Water scarcity and unpredictability
- Specialized soil life adapted to dry and extreme conditions
- Underlying role of fire in shaping many dryland ecosystems
- Adaptive capacity of species and ecological interactions in arid regions
- Social and cultural adaptation to living in the drylands
- Vulnerability to climate change
Managing Drylands Sustainably
Because land degradation is often the result of multiple drivers, responses need to be tailored to particular situations. Sustainability requires many steps, from holistic management approaches to crop selection and production, livestock raising, and water conservation as well as a suite of enabling factors. These include:
- Sustainable cropping
- Rangeland management
- Water security
- Policy incentives
- Research and capacity building
- Investment to reverse land degradation in the drylands.