Desertification - a growing problem

by Pramod de SILVA

Can you imagine a desert exactly the size of Sri Lanka (65,610 Sq Km)? If we place Sri Lanka in the Mojave Desert in the USA, they will match almost perfectly. But if it is difficult to imagine a desert the size of Sri Lanka, Sahara, the world's biggest desert, would be mind-boggling at 9,400,000 square kilometres. We can easily place 143 islands of Sri Lanka's size there. Indeed, that is a very big land area!

Amazing as that may seem, deserts are getting bigger all the time in a process called desertification - the persistent degradation of dryland ecosystems by human activities and climatic variations. The term desertification was first coined by French scientist and explorer Louis Lavauden in 1927.

Desertification was defined at the Rio Earth Summit in 1992 as degradation of drylands, the point at which that land no longer can be returned to a productive state.

Because of its toll on human well-being and on the environment, it ranks among the greatest development challenges of our times. Deserts are not totally 'dead' in the strictest sense of the word, for life finds a way even in the harshest of environments. But desertification means the loss of valuable arable lands and forest land. It is happening, albeit slowly, everywhere.

About one-third of the world`s land surface is arid or semi-arid. It is predicted that global warming will increase the area of desert climates by 17 percent in the next few decades. Worldwide desertification is claiming 20,000 square miles of land annually. Even the Sahara desert is advancing southwards by about 5-10 kilometres per year.

Desertification has now become a worldwide issue and many countries are keen to stop desertification on their soils, literally. This is why the UN has proclaimed a World Day to Combat Desertification and Drought. It is observed all over the world on June 17 every year.

The aim of the United Nations in designating a day of observance is to educate the public and policy-makers on the increasing dangers of desertification, land degradation and drought.

Environmental events

This year's environmental events are centered on one theme: Forests. This is the International Year of Forests. The World Environment Day on June 5 was celebrated on the theme Forests: Nature at Your Service.

On the same lines, the World Day to Combat Desertification for 2011 will focus specifically on the forests in the dry land areas of the world, guided by the motto: 'Forests keep drylands working'.

As the UN points out, desertification, land degradation and drought (DLDD) threaten human security by depriving people of the means to decent livelihoods. They undercut food production, access to water and the means to economic activity, and even destroy their homes.

Turning to the theme for the year, land degradation in the drylands (desertification in other words), begins with the clearing of vegetation.

"Forests are the first step towards healing the drylands and protecting them from desertification and drought," says Luc Gnacadja, Executive Secretary of the UN Convention to Combat Desertification.

Dry forests may become the single most important determinant of the future sustainability of the drylands as the impact of climate change escalate. Yet, only 18 percent of the drylands is forested.

In his call to the international community in February when unveiling the 2011 theme, Gnacadja said, "If each of us makes the commitment and ensures that just one tree is planted in a degraded part of the drylands and that the tree survives through the year, we could have well over two billion trees in the drylands by the end of the year. That is a tree for every inhabitant. Let us go forth and forest the drylands to keep them working for present and future generations."

This is indeed a noble call, for trees literally mean life for the two billion inhabitants that call drylands 'home'. They provide food and medicine for the people and their livestock. They are their places of worship and shelter and their decision-making centres.

Food security

These forests are the 'invisible' backbone of humanity's food security. One in every three plants under cultivation originated here and now provide globally-consumed crops such as wheat, barley, sorghum, corn, cabbage, potatoes and olives.

Thus, saving the drylands has become a priority especially in places where desertification is rife such as Africa and even South America. The recent African Drylands Week was a step in this direction.

Drylands are in the spotlight due to another unlikely reason. The pressure on arid zone forests that protect them may increase, especially in the tropical and sub-tropical regions, from two opposing forcesw.

There is a global campaign to conserve the moist tropical forests for carbon sequestration, on the one hand, and the need to open up new land for agriculture to meet a growing global demand for biofuels, food and poverty eradication on the other.

Increasingly, this pressure is being eased by reverting to the drylands.

Thus drylands too are being cut down and reduced, which could lead to desertification. No country is immune from desertification in this light as the unsustainable use of local resource continues everywhere.

But desertification can be prevented and even reversed in rare instances. Establishing seed banks, reintroducing selected flora and fauna, countering erosion, enriching the soil with nutrients and planting trees in the drylands are some of the suggestions made by agricultural and climate experts.

The sustainable use of all dryland resources is another. More efficient use of existing water resources (better irrigation practices) and control of salinisation are other effective tools.

Climatic phenomenon

Drought is a climatic phenomenon closely linked to desertification. It is a climatic condition that prevails when there is little or no rain in a given geographical area. Any country can face a drought - remember the long drought in Sri Lanka in 1996? A drought can last for a week, or for several years at a stretch. The UN estimates that an area of fertile soil the size of Ukraine (603,700 Sq Km) is lost to agriculture every year due to drought.

What can we do to prevent drought? In the long term, reforestation is an ideal answer. Among the other steps are better agricultural practices such as crop rotation (slash and burn cultivations increase the risk of drought), streamlined land use, outdoor water use restrictions (such as on washing cars), rainwater harvesting, recycling water and building better irrigation systems in drought-prone areas.

Limiting grazing by livestock is another option. Like desertification, droughts affect billions of people worldwide.

These are two inter-connected issues that the international community must address without delay in the run-up to the 2012 Earth Summit in Rio. Desertification and drought affect not only the climate patterns, but also the livelihoods of billions around the world. It is not a completely lost cause as outlined above, there are plenty of steps that can be taken to stop desertification along the drylands.

The World Day to Combat Desertification is an ideal opportunity to embark on such ventures on a worldwide scale. On an individual level, a simple act such as planting a tree can contribute to controlling desertification even in a small way.

This fits in ideally with the overall theme of forests for this year's environmental activities too.