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Among the land used for agriculture and forestry, soil is an impor-
tant component. The intense and increased pressure on land leads to 
its degradation and pollution, which may result in a partial or com-
plete loss of its productive capacity. Soil degradation can be described 
as a process by which one or more of the potential ecological func-
tions of the soil are harmed. These functions relate to bio-mass pro-
duction (nutrient, air and water supply, root support for plants) to fil-
tering, buffering, storage and transformation (e.g. water, nutrient, pol-
lutants). Soil degradation is defined as a process that lowers the cur-
rent and/or future capacity of the soil to produce goods and services. 
Two categories of a soil degradation process are recognized, dis-
placement of soil material (e.g., soil erosion by water forces or by 
wind forces) and soil deterioration covering chemical or physical soil 
degradation. 
Soil degradation is on the increase worldwide, especially in the 
countries within the tropics. Mismanagement of arable areas by farm-
ers and grazing areas by livestock owners is one of the major causes 
of soil degradation. More sustainable management of lands would re-
duce environmental pressures. Conservation tillage, i.e. reduced or no 
tillage, is the key to sustainable arable land management as it protects 
the soil resources, increases the efficiency of water use and, of special 
importance in semi-arid areas, reduces the effects of droughts. 
Land/soil degradation can either be as a result of natural hazards or 
due to unsuitable land use and inappropriate land management prac-
tices. Natural hazards include land topography and climatic factors 
such as steep slopes, frequent floods and tornadoes, blowing of high 
velocity wind, rains of high intensity, strong leaching in humid re-
gions and drought conditions in dry regions. Deforestation of fragile 
land, over cutting of vegetation, shifting cultivation, overgrazing, un-
balanced fertilizer use and non-adoption of soil conservation man-
agement practices, over-pumping of ground water are some of the fac-
tors which comes under human intervention resulting in soil erosion. 
The United Nations Environment Program (UNEP) formulated a 
project proposal for Global Assessment of the Status of Human In-
duces Soil Degradation. This was achieved with the help of more than 
200 soil scientists and environmental experts worldwide. The project 
also received active advice from the International Society of Soil Sci-
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ence. Regional cooperators were asked to delineate on a standard to-
pographic base map units showing a certain homogeneity of physi-
ography, climate, vegetation, geology, soil and land use. Within each 
delineated map unit, soil degradation, its relative extent within the unit 
and the type of human intervention that has resulted in soil degrada-
tion during the post-war period were also indicated. The regional re-
sults were then generalized and compiled as a world map.
The program developed methodologies to create soil and terrain 
databases. The main objective of the program was to strengthen global 
awareness of policy-makers and decision makers of the danger result-
ing from inappropriate land and soil management.

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