Desertification is defined as land degradation in arid, semi-arid, and dry sub-humid areas resulting from many factors, including climatic variations and human activities (United Nations Convention to Combat Desertification (UNCCD
Land degradation is a negative trend in land condition, caused by direct or indirect human-induced processes including anthropogenic climate change, expressed as long-term reduction or loss of at least one of the following; biological productivity, ecological integrity or value to humans. And, semiarid, and dry sub-humid areas, together with hyper-arid areas, constitute drylands (UNEP, 1992), home to about 3 billion 10 people (van der Esch et al., 2017). The difference between desertification and land degradation is not process-based but geographic. Although land degradation can occur anywhere across the world, when it occurs in drylands, it is considered desertification. Desertification is not limited to irreversible forms of land degradation, nor is it equated to desert expansion, but represents all forms and levels of land degradation occurring in drylands.
A VICIOUS CYCLE
Today, over 250 million people are already directly affected by land degradation. Africa is particularly threatened because land degradation processes have spread to about 46 % of the continental area. Asia, on the other hand, is the worst hit in terms of the number of people afflicted by desertification and drought. The world’s drylands not only make up 34 % of the global population, their soils contain over a quarter of all of the organic carbon stores in the world as well as nearly all the inorganic carbon. Drylands are home to eight of the world’s 25 identified biodiversity hotspots. They are also among the earth’s most fragile ecosystems. Climate change aggravates drought, which aggravates land degradation. Land degradation, in turn, releases carbon stored in the soil, thus worsening global warming and climate change.
CAUSES OF LAND DEGRADATION
Here are three proximate causes of land degradation, from UNDP’s perspective; Insecurity of land tenure. Farmers throughout the developing world subsist under complex arrangements of land tenure that do not provide them with the necessary guarantees of future rights that are essential to anchor land rehabilitation. Women are frequently the primary land managers but all too often have no rights of ownership or inheritance. Without attention to the gender aspects of land governance, we will make little progress.
Unwise land-use changes. Forests are being cut down for agricultural livestock. Range lands are being transformed into crop lands. Wetlands are being drained. Farmers are now farming hill-tops. The farmers of the world are being called upon to feed a growing world population. This makes agriculture the most important driver of land use, land change and degradation.
Farmers are the guardians of land and can be our most important agents for land management and rehabilitation. Agricultural research, too, can be a great ally: millions of farmers in India are already using new and advanced techniques of conservation tillage that preserves soil while ensuring high yields. We need to re-energize our approach to investing in agriculture with an emphasis on conservation and rehabilitation.
Likewise, we must urgently develop better policies for land use and, where necessary, reverse changes that have taken place. We also need better science to help us understand land degradation and how to restore land. While the Millennium Ecosystem Assessment has helped us understand the scale and causes of land degradation, much more needs to be done. Biodiversity conservation will depend ultimately on land-use decisions.
Land management is also an instrument both for climate-change adaptation and for mitigation. Well-managed, well-restored land will withstand changes in rainfall and temperatures far better than degraded land. Well-managed land with good tree cover will sequester carbon. Local land management and restoration is thus an important part of the fight against global climate change
By Amelia Joannie Zanette
