Land degradation is on the rise, affecting around 3.2 billion people worldwide, yet insufficient efforts have been made so far to ensure sustainable land use and the protection of soils. This is the message of a new book presented at a press conference in Berlin last week. An international team of scientists from Bonn’s Center for Development Research and other institutions conducted case studies for 12 countries in different world regions. Their findings, which are partly based on satellite data, are alarming: 33% of grasslands, 25% of croplands and 23% of forests experienced degradation over the last three decades. About 30% of global land area, which is home to about 3.2 billion people, has experienced significant degradation. Land degradation is a serious problem in both low- and high-income countries and in both temperate and tropical regions, the scientists concluded. “If we talk about fighting the root causes of mass migration, then land degradation is an important factor. When people cannot grow their own food, they will think about moving elsewhere”, Klaus Töpfer, former head of the United Nations Environment Program, was cited by Deutsche Welle. According to the book, the global costs of land degradation amount to about US$300 billion per year, or about 0.4% of the 2007 global gross domestic product. The assessment found that the costs of doing nothing about land degradation are several times higher than the costs of taking action to reverse it: Every dollar invested in saving land and soils today will save us five dollars in the future. The poor are hit hardest by land degradation because their livelihoods heavily depend on natural resources. Africa south of the Sahara accounts for the largest share of the total global cost of land degradation with 26%. Often, there is a lack of extension services for farmers, for example about soil fertility management, the authors said. Another problem is weak security of land tenure. Several case studies showed that the adoption of sustainable land management practices is often dependent on secure land tenure. The authors therefore stressed the need for policies which protect customary tenure systems against arbitrary expropriation as well as for long-term strategies for enhancing women’s access to land under customary tenure. It is high time to take action against land degradation, the researchers said. “Sustainable land management contributes to achieving several of the Sustainable Development Goals (SDGs), such as land degradation neutrality and an ambitious climate and biodiversity agenda,” said Professor Klaus Töpfer. Goal 15 of the 2030 Agenda for Sustainable Development adopted by the UN in autumn aims at halting and reversing land degradation. (ab)