Periódicos Brasileiros em Medicina Veterinária e Zootecnia

O processo de desertificação e os riscos de sua ocorrência no Brasil

M. Fearnside, Philip

Summary This paper presents a brief overview of the process of desertification on a world wide scale, and explains how individual factors contributing to this process apply to different regions of Brazil. Human activities have often been significant causes of climatic change in the direction of dryness, obten in combination with geographical factors such as global air circulation patterns, mountain rainshadows. and cold ocean currents. The key role of human overexploitation is documented in a more detailed examination of the specific example of the Rajasthan Desert in north-western India. The role of atmospheric dustiness resuiting from overgrazing and cultivation of marginal lands has been a particularly important factor in the case of this overpopulated man-made desert. The dangens of desertification are examined with respect to the different situations in the various regions of Brazil. Special emphasis is given to the rainfall-reducing effects of deforestation in the Amazon Basin. Underlying causes of the exploitation patterns which result in climatic deterioration are discussed, and suggestions are given for minimizing the danger of desertification in Brazil.

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