The world’s drylands occupy a vast region and are home to more than 2.5 billion people. Many of the world’s regions are adversely affected by desertification and the concept of desertification is rooted in the charter of the United Nations Convention to Combat Desertification (UNCCD). UNCCD was adopted in 1994 and is the first international treaty to, amongst other things, emphasize the need for an integrated approach to combating desertification which includes activities as part of the integrated development of land in arid, semi-arid and dry sub-humid areas which are aimed at the prevention and/or reduction of land degradation; rehabilitation of partly degraded land and reclamation of desertified land.
Serious land degradation is a problem that many countries face. The economic costs are significant but human tragedy of crops and animals destroyed, and lives lost bring home the true nature and extent of the problem. Add to this are the impact on biodiversity and the impact on global climate change as the albedo changes.
Desertification often results from the degradation of the vegetation cover by overgrazing, over trampling, fuelwood collection, repeated burning, or inappropriate agricultural practices, which leads to a general decrease in the productivity of the land and in accelerated degradation of soil resource, and eventually affects the capacity of the vegetation to recover and constitutes the principal mechanism of irreversible damage to the environment. Therefore, the real task of combating desertification is one of implementing more sustainable land use practices and changing the enabling environment that will allow better stewardship to take root and prosper.
It is ingrained in our minds that deserts equate to Africa. In fact, there are deserts, arid and semi-arid regions in China, South America and even in North America as well. Holistic approach to proper ecosystem land management is employed. It is a long tough road.
China is one of the developing countries with vast deserts and desertified areas and 60% of its population is living in the affected areas. China has been severely hit by persistent drought and desertification. Although drought and desertification must be distinguished, they can amplify each other’s impact.
North Africa has a Mediterranean climate with hot dry summers and cool wet winters. Large area of the land of countries like Libya, Morocco and Egypt are classified as deserts or semi-desert and land use is governed by water availability. Soil loss from wind and water erosion and overgrazing of the steppes by livestock are common immediate cause of desertification. Over the last century there has been a decrease in rainfall throughout the Mediterranean region. Climate change predictions for North Africa show rising temperatures with potentially grim impact on the region’s already stressed resources including food and water.
Terminology and Definitions
Desertification: In the early years of worldwide efforts to combat desertification, there have been misunderstanding and misguided practices due to lack of clarity in the definition of the subject. It is for this reason that defining relating concepts clearly and consistently is of paramount importance in treating combating desertification as a worldwide environmental issue. To date, most countries have agreed to adopt the definition adopted by UNCCD. Desertification is now taken as land degradation in arid, semi-arid and dry sub-humid areas resulting from various factors, mainly climatic variation and changes and human activities. Desert regions where P/ETP<0.05 are excluded. Desertification does not refer to the expansion of existing deserts. It occurs because dry land ecosystems, which covers over one third of the world’s land area, are extremely vulnerable to over-exploitation and inappropriate land use practices.
A consequence of misunderstanding about desertification, fuelled by the belief that desert spreading is the primary problem, is the planting in sand dunes but the benefit/cost ratio of such planting is low or negative. Progress in combating desertification requires a major re-think and the application of holistic approaches such as Integrated Ecosystem Management.
Land Degradation – means reduction or loss of the biological or economic productivity and complexity of rain fed cropland, irrigated cropland, or range, pasture, forest and woodlands resulting from land use or from a process or combination of processes, including processes arising from human activities and habitation patterns, such as soil erosion caused by wind and/or water; deterioration of the physical, chemical and biological or economic properties of soil; and long-term loss of vegetation.
Arid, semi-arid and dry sub-humid areas – mean areas other than polar and sub-polar regions, in which the ratio of annual precipitation to potential evapotranspiration falls within the range from 0.05-0.65. Hyper-arid areas, including real deserts such as the Sahara and China’s Taklamakan were excluded from the UN definition.
Combating Desertification in Asia, Africa and the Middle East – Proven practices, G. Ali Heshmati, Victor R. Squires (editors), Springer Netherlands, 2013, ISBN 978-94-007-6651-8, 476 pp.