Land degradation and subsequent desertification are becoming some of the most pressing development issues. It is estimated that one-third of the world's arable land has been lost in the last 40 years due to soil erosion. Every year, 24 billion tons of fertile soil is lost through erosion and 12 million hectares of land are degraded through desertification and drought. These processes directly threaten the livelihoods of 1.5 billion people, and have broader consequences on growth and prosperity at the national and regional level. In countries such as Central African Republic, Egypt, Ghana, Pakistan and Tajikistan, land degradation is estimated to cause an annual GDP loss in the order of 1 to 5%.
Pressure on land resources is expected to increase, largely driven by socio-economic development, as well as climate change. According to the FAO, population growth will lead to a 50% rise in the demand for food by 2050. The need to produce more food will increase the risk that land which is unsuitable for intensive farming -- or which should be protected to prevent de-forestation or biodiversity loss -- will be claimed for agricultural purposes. It thus also increases the risk that such land will become degraded.
The threat is exacerbated by climate change driven by warmer temperature and more erratic rainfall patterns. The yield of major crops such as wheat, rice, and maize could decline in the coming decades by 25% or more in currently cultivated areas. This will further increase the incentives to move the agriculture frontier into marginal lands. At the same time, cultivable areas themselves may shrink as a result of climate change. In Sub-Saharan Africa, for example, drylands could expand by up to 15% in the next few decades, forcing more people to struggle to make a living from a fragile resource base and adapt to the constraints of an increasingly erratic weather.
Desertification is one of the concerns in the post-2015 development agenda. The recently released Zero Draft of the UN Open Working Group -- proposing goals and targets for the post-2015 development agenda -- includes a goal to "Protect and promote sustainable use of terrestrial ecosystems, halt desertification, land degradation and biodiversity loss." The goal is accompanied by specific targets which cover issues ranging from desertification and drought to biodiversity and natural resource management.
To address the unique issues faced by the most vulnerable, we must invest in applicable solutions that are transformative, and can be scaled up. For example, as part of the TerrAfrica partnership, we are working in 12 countries to support the Great Green Wall Initiative of African countries to boost resilience. Together with a large number of partners, we are also working on a major study on The Economics of Resilience in the Drylands of Sub-Saharan Africa to determine the interventions needed to reduce the vulnerability and enhance the resilience of people living in drylands.
We must, however, be more ambitious and scale up efforts to support appropriate solutions for better management of land and other natural resources at the farm, community, landscape and national levels. The following are some of the priority areas for action by governments and the international development community, in partnership with the private sector and civil society.
First, we need to create a better enabling environment for people to invest directly in land management. Well-defined, transparent, and secure land tenure systems are essential if farmers are to undertake the long-term conservation that underpins agricultural production and investments to improve natural capital and productivity. In Rwanda, for example, land tenure reform led to a rapid doubling of investment in soil conservation, with even larger increases for plots managed by female farmers.
Second, we need to support investment in lasting improvement of natural resources. For example, climate-smart approaches to agriculture can be employed that minimize soil disturbance, make greater use of organic soil, and support diversification of crop species. Environment-friendly benefits of these approaches include reduced nutrient pollution of soil and water, increased resilience to climate shocks, and increased long-run agricultural productivity. But switching to climate-smart approaches may involve up-front costs, which may impede wide-spread adoption. Public support -- through credit, extension and support to market access -- is needed to help overcome these.
Third, cost-effective support to research and development is essential. In Brazil -- where state support of agriculture is just 5 percent of aggregated gross farm receipts, compared with an OECD average of 18 percent -- the government has concentrated on investments in soil fertility enhancement, land and water management systems, and crop and livestock breeding, for varieties adapted to Brazil's climate and ecosystems. Brazil's public support of research and soil fertility has paid off, helping transform the country from a net food importer into a global food exporter.
Fourth, in some cases, direct public investment in landscape restoration and rehabilitation can bring about sizable livelihood benefits and create better conditions for attracting further investments by farmers and communities. The China Loess Plateau and Ethiopia's cases are well-documented success stories of landscape restoration. Similar experiences are being promoted in other parts of the world.
Actions to reduce the negative effects of desertification must go hand in hand with interventions that eradicate poverty and deal with the challenges of inequality. We will not end poverty and boost shared prosperity without reversing desertification and land degradation.
Looking forward, the World Bank and its partners have a critical role to play with tackling the inter-linkages between desertification, drought, food insecurity, climate change and political instability. It is time to act. Discussions on the post-2015 development agenda provide an opportune moment to build the partnerships required to catalyze the knowledge, innovation, and financial resources needed to reverse and prevent desertification.