期刊名称：Science et changements planétaires / Sécheresse
印刷版ISSN：1147-7806
电子版ISSN：1777-5922
出版年度：2006
卷号：17
期号：1
页码：275-287
出版社：John Libbey Eurotext
摘要：Figures See all figures Author Henri Noël Le Houérou 327, rue A.L. De Jussieu, Montpellier France Key words: rainfall, range, animal husbandry, pastoralism, Brazil, Nordeste, arid zone, drought Page(s) : 275-87 Published in: 2006 North East Brazil is rightly considered as a semiarid zone periodically stricken by severe multi-annual droughts and alternatively by recurrent torrential rains. This paper studies the variability of annual precipitation in order to try and do justice of some legends. The size of the area varies with authors and purpose of information. But the drier part (250-600mm of mean annual rainfall), the Sertao, includes some 600,000 km 2. Vegetation is essentially constituted of the Caatinga a high, drought-deciduous shrubby vegetation dominated by legume trees and shrubs and native unpalatable Cactaceae. Rangelands are very poor, essentially constituted of ephemeral annual grasses of low production potential, but browsing may occasionally correct this deficiency. Contrary to the climatically similar region of East Africa, livestock husbandry is settled and land privately owned. The traditional anti-drought strategy used to be based on the feeding of livestock with planted spineless cacti (0.5 million hectares in 1992) in periods of drought, but recently graziers have moved to sown tame pastures based on perennial grasses, in conjunction or not with water resource development and the utilization of agriculture residues and agro-industrial by-products.
