food and agriculture > factfile > desertification and degraded land
Desertification and degraded landPosted: 14 Aug 2003
"Desertification is essentially about people. People cause degradation and they are the sufferers from it. Unsustainable land management practices caused by inadequate farming techniques or increasing population pressures fuel land degradation, especially in susceptible drylands."
Klaus Toepfer, Executive Director, United Nations Environment Programme
Desertification is not the spread of existing deserts, but rather the loss and destruction of healthy fertile soils.
Loss of topsoil and soil fertility results in declining production of crops and livestock. When soil is lost or degraded, people are not able to produce as much as before, and often, not enough for their needs.
Overall, the problem is caused by people putting too much pressure on delicate soils and ecosystems. In places where there is little rain, the soil is already fragile and overuse by humans can easily destroy it. The UN calls these areas, "arid, semi-arid, or sub-humid"�in other words, "dry." The main causes of land degradation include:
Overgrazing � Too many livestock, such as goats or cows, strip the soil of its vegetation and expose it to erosion by wind and water;
Deforestation � Trees hold the soil together and help water the land by channeling rainwater into the soil. When they are chopped down, the soil is eroded by the elements and is unable to hold water;
Overfarming � Overworking the land eventually drains the soil of its nutrients, leaving it unable to produce crops;
Poor irrigation practices � Bad irrigation can lead to waterlogging and salinisation of the soil.
Over one-quarter of the Earth�s land surface has already suffered erosion and soil degradation. The U.N. Environment Programme (UNEP) calls desertification "one of the most serious global environmental problems." It threatens the health and livelihoods of over one billion people�mostly poor rural families in developing countries.
According UNEP, soil degradation could have affected 1,900 million hectares of land worldwide. In China, between 1957 and 1996, the area of arable land was reduced by an area equivalent to all the cropland in Denmark, France, Germany and the Netherlands, largely as a result of land degradation. According to the International Food Policy Research Institute, (IFPRI), the cumulative productivity loss from soil degradation over the past 50 years is estimated at 13 per cent and 4 per cent for pasture lands.
Tree nursery for reafforestation at Gour, Niger. Credit: FAO
Desertification is directly linked to poverty and can lead to famine, malnutrition, starvation, epidemics, economic and social instability and mass migrations. More than 70 per cent of agriculturally used drylands in Africa, Asia and Latin America are already affected.
Drylands are home to over 2 billion people worldwide living in some 100 countries in rural areas and urban centres, i.e., nearly 40 per cent of the world's total population. As fertile soil is degraded, those who rely on the land are less able to grow or get food, and their hopes for a better life are diminished. For those that live in cities, or in wetter climates, problems of desertification in drylands may seem far away. But its effects touch everyone:
- When poor farmers or herders can�t produce enough food, their lives are in danger. Millions of dollars are diverted into emergency aid. Waves of environmental refugees are driven to the cities, which are often unable to accommodate and help them. The results are overcrowding and unemployment. Social and political unrest frequently follows.
- Wild species native to the world�s drylands are being lost forever. Many of the world�s staple grain crops were originally wild dryland species. When the natural dryland flora disappears, we lose the chance to discover new crops that can help to feed humanity.
- We all live off the land, even if we buy our food from shops and markets in the cities. It is a problem for all of us that the world�s population is growing, while our fertile agricultural lands are declining.
Women are especially important in finding solutions because in many of the dry, agricultural areas of the world � including much of Africa � it is traditionally women who devote time and effort to the land.
It is, therefore, of vital importance not only to provide women with technical and financial resources, but also to bring about changes in attitudes among women, and society as a whole. Governments need to create "enabling environments" that will empower women and engage them as "full partners" in this effort to preserve the land.
Some more facts and figures:
- Drought and desertification threaten the livelyhood of more than 1.2 billion people in some 110 countries - with 135 million at risk of being displaced.
- Arable land per person has declined from 0.32 hectares per person in 1961-63 to 0.21 hein 1997-99 and is expected to drop further to 0.16 hectares by 2030.
- Around 6 million hectares of productive land are lost every year as a result of desertificaton and declining productivity.
- In 2002, Australia lost millions of tons of productive land in dust storms. In India dry spells and desertification turn 2.5 million hectares into wasteland every year. In Mexico, where 70 per cent of the land is subject to desertificaton, some 900,000 people leave the countryside each year in search of a better life. The number of environmental refugeees in sub-Saharan Africa is expectd to rise to 25 millions in the next 20 years.
- In November 2002 huge dust storms moved across China towards Korea and the Pacific, part of a long-term pattern of desertification which has accelerated in the past 50 years. According to the Chinese Academy of Sciences, growing population and increased human activity are to blame. Land for food production was halved per capita between 1950 and 1990.
This section was provided by EarthAction, with additional facts from the United Nations, the Environmental News Service (ENS) and World Watch magazine.
FAO Website on Desertification.