ABSTRACT
Land degradation is a composite term; it has no single readily identifiable feature, but instead describes how one or more of the land resources (soil, water, vegetation, rocks, air, climate, relief) has changed for the worse. The change may prevail only over the short term, with the degraded resource recovering quickly. Or it may be the precursor of a lengthy downward spiral of degradation, causing a long-term, permanent change in the status of the resource. Take, for example, a landslide. It is often viewed as an example of land degradation in action: it changes the features of the land, sweeps away productive resources, causes destruction of houses and disrupts activities. The landslide creates massive and disastrous change. In the longer term, however, the area of a landslide may regain its productivity. In places such as Jamaica and Papua New Guinea, old landslide scars are noted for supporting better crops and more intensive agricultural possibilities than the adjacent land not affected by landslides, especially when the new soil is derived from less weathered rock materials, such as calcareous mudstones. The irony of degradation leading to long-term improvement of the natural resource base has not been lost on local people. They are quick to exploit the new opportunities. So, land degradation is far from being a simple process, with clear outcomes. This complexity needs to be
appreciated by the field assessor, before any attempt is made either to define land degradation or to measure it.
