DESERTIFICATION

Desertification undermines the land's productivity and contributes to poverty. Prime resources, such as fertile topsoil, vegetation cover and healthy crops are its first victims.

Consequent to the Government of Barbados becoming signatory to the Convention to Combat Desertification, the Ministry of the Environment, Energy and Natural Resources decided that an integrated position in relation to desertification in our context should be taken and there was need to identify potential strategies for its combat and/or the mitigating effects, thus the establishment of the Desertification and Drought Committee.

In Barbados, instances of desertification are not as severe as in other parts of the world, however our history has demonstrated that Barbados and other Caribbean islands have been victims of land degradation. This in principally linked to the extensive deforestation measures which were undertaken in support of agriculture.

THE FACTORS OF DESERTIFICATION

• Deforestation
• Over-grazing
• Over-cultivation
• Poor Irrigation Practices

Such over-exploitation is usually induced by Economic pressure, Social Pressure, Ignorance, War, Drought

As a result of the above vegetation and topsoil losses due to desertification generally signals the onset of a number of other environmental problems including the following:

• Increase surface runoff and stream discharge.

• Reduction of water infiltration and groundwater recharge.

• Development of erosional gullies and sand dunes.

• Change in the surface microclimate that enhances aridity

• Drying up of wells and springs.

• Reduction in seed germination of native plants.

AN INNOVATIVE SOLUTION
Combatting desertification is essential to ensuring the long-term productivity of inhabited drylands. To address this matter, some 120 governments have joined the United Nations Convention to Combat Desertification.

Drawing on past lessons, the Convention stated that programmes aimed at combatting desertification must incorporate local community participation.  

CONTROLLING SOIL EROSION
There are many possible ways of reducing soil erosion in an area which is at risk.

These include the following.

• Land around a gully can be fenced in and planted with grass and small trees.

• Check dams can be built across gullies to slow down the flow of water. Even a barrier of brushwood is of some use in a small gully.

• Steep hillsides can be terraced. Terraces convert a sloping hillside into a series of steps, so that rainwater does not rush straight downhill.

• Some crops can be grown in ridges, which run along the slope and also prevent water from running straight downhill. Ridges are rather like small-scale terraces. They are much easier to construct, but do not work very well on a really steep slope.

• When the land is ploughed, furrows which run straight up and down the slope are disastrous, because they actually encourage the formation of rills and gullies. Contour ploughing, which follows the slope of the land, is much less damaging.

• A suitable cropping pattering is probably the most important conservation measure of all. It is much better to plant a mixture of different crops, rather than one single crop, which will leave the soil completely unprotected after the harvest.

• Planting different crops in strips, which run along the contours is also useful. When one crop has been harvested, only a narrow band of soil will be left exposed; the runoff water will not be able to gather speed or do any real damage.

• Tree crops are very useful, because their roots help to stabilize the soil all year round. It is also a good idea to plant a cover crop to protect the soil on land which has just been harvested. Before the next crop is planted, the cover crop can be fed to animals or ploughed back into the soil.

• The farmer should also try to maintain the amount of humus in the soil. Soil which has a good crumb structure is much less likely to be eroded by the wind or rain.

• Some areas are simply not suitable for cultivation at all. On very steep slopes, the land should be used for pasture or, in some cases, forest.