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机构地区:[1]中国科学院兰州沙漠研究所
出 处:《中国沙漠》1991年第2期39-45,共7页Journal of Desert Research
摘 要:河北坝上高原现代土地沙漠化发展迅速。研究表明,近十多年来(1975—1987)每年以173.5Km^2的速度蔓延,人类不合理经济活动做为主导因素叠加于半干旱气候条件上造成其发展,主要表现是:地表在风蚀——风积过程中,可利用土地资源逐渐丧失。The present land desertification has been developing rapidly. From 1975-1987, the desertificd land spread 2085sq. km. , increassd by 6. 89% annually in Bashang plateau, Hebei province. During last four decades, the climatic change in studied area was not obvious and no directional changing tend can be found, but the human economic activities have increased continually. Under the semi-arid climatic condition, the process of desertification was caused mainly by the over-reclamation and overgrazing, and resulted in the decline of biomass productivity and the loss of land resources through wind erosion.
分 类 号:S288[农业科学—农业水土工程]
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