Factors affecting losses of soil and agricultural land in tropical countries
Commonly, constraints on agricultural development in tropical regions are frequently mainly soil or soil related. In the Amazon Basin, for example, the soils are commonly of inherently very low fertility, but many have relatively good physical properties. Inappropriate clearance of the forests may result in undesirable soil physical properties which impose an additional constraint on food production in this region. In addition, where such clearance takes place on sloping lands, soil erosion may be a major hazard.
In arid regions where arable crops can only be produced with the aid of irrigation, it is imperative that available water is used efficiently. The management of the soil-water store is a key feature in the development of sustainable agricultural systems in these areas, also the development of crops and crop-rooting systems which can maximise water use under these conditions. A further limiting factor to development is the nature of the water available for plant growth, as salinisation resulting from the application of poor quality water is a major constraint unless excess salts can be leached from the system.
Successful agricultural development in the tropics must take place with the full recognition of the relationship between the soil and the other environmental components.
KeywordsSediment Yield Amazon Basin Soil Water Store Evaporative Demand Humid Tropic
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