Why digging sand could save lives

Understanding the causes of desertification can help prevent its damaging social effects, writes Jarle Hetland.

For thousands of years mankind has struggled with and tried to combat desertification, but more recently, with increased global warming and a growing population, the phenomenon has become more urgent.

The United Nations estimates that more than one billion people living in more than 110 countries are threatened by desertification. The risk of conflict over scarce resources is growing. The conflict in Darfur, for example, is seen by many as a direct result of increased desertification. In sub-Saharan areas, nearly 70% of the land is either desert or dry land and the threat of conflict is ever-present.

Although most people think of desertification in Europe as a problem for the southern countries on the Mediterranean, a drier climate is leading to the degradation of land further north too. Belgium, the UK and even the Netherlands are all experiencing some sort of desertification - albeit to a lesser degree than Greece and Spain.

Across the world, scientists are busy looking at how to deal with the phenomenon. One such project looking for a remedy to desertification is Desire, which is co-ordinated by Coen Ritsema of the Alterra Wageningen University and Research Centre in the Netherlands. Desire, which is funded by the EU's sixth framework programme for research and national governments, involves research institutions, non-governmental organisations and policymakers across the globe. Launched in March last year, Desire has a budget of Û9 million for the five-year duration of the project.

Ritsema characterises desertification as initiated by two main causes - a changing climate and pressure on the land from people, for example through intensive agriculture.

Ritsema and his colleagues are hoping to come up with integrated conservation approaches that can reduce or even prevent widespread land degradation. Climate change, water and wind erosion, forest fires and soil salination all contribute to an increase in arid land. The Desire team has identified 18 so-called hotspots in Europe, Australia, Latin America and the US affected by one or more desertification-related problems (see table above). By studying the different regional approaches to preventing land degradation and combining these findings with modern scientific research, the Desire team hopes to find innovative solutions.

"What we are trying to understand is: what does dryness do to the soil system and what can we do to limit the soil from drying," Ritsema says. In dried-out soil, the properties have changed, which is something irreversible. The soil is rendered obsolete as it is unable to absorb water. Ritsema says understanding the irreversible threshold is crucial to limiting land degradation.

Although Desire's main aim is to develop new methods and strategies for the use and protection of vulnerable areas from desertification, the research undertaken by this and similar projects could prove vital in preventing further conflicts, as well as limiting migration and reducing poverty across the world.

Desire's hotspots

Area: Main Problem

Murcia, Spain: Drought, soil erosion by water

Ma‹o, Portugal: Forest fires

Basilicata, Italy: Soil erosion by water

Crete, Greece: Soil erosion by water, overgrazing, water stress

Maggana, Greece: Salinisation

Konya Karapinar Plain, Turkey: Soil erosion by wind

Eskisehir Plain, Turkey: Soil erosion by water

Mamora/Sehoul, Morocco: Increasing pressure due to urbanisation nearby

Zeuss-Koutine, Tunisia: Competition for scarce water resources

Djanybek, Russia: Poor vegetation growth

Novij, Saratov, Russia: Salinisation

Loess Plateau, China: Soil erosion by water and wind

Boteti Area, Botswana: Overgrazing and decreased flooding

Cointzio catchment, Mexico: Soil erosion by water

Walnut Gulch Watershed, US: Vegetation change, flash floods

Glenelg Hopkins region, Australia: Salinisation and sporadic bush fires

Secano Interior, Chile: Soil erosion by water, extensive gullying

Santiago Island, Cape Verde: Soil erosion, drought, flash floods

Understanding the causes of desertification can help prevent its damaging social effects, writes Jarle Hetland.