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中国沙漠 ›› 1988, Vol. 8 ›› Issue (1): 1-8.

• 论文 •    下一篇

半干旱地区沙漠化发展的内在动因

刘恕   

  1. 中国科学院兰州沙漠研究所
  • 出版日期:1988-03-20 发布日期:1988-03-20

Internal Dynamic Causes of Desertification Development in Semiarid Zone

Liu Shu   

  1. Institute of Desert Research, Academia Sinica
  • Online:1988-03-20 Published:1988-03-20

摘要: 我国半干旱地区(年降水等雨线250-450mm之间的地带)存在着严重的环境退化问题。这里分布着54.0万km2黄土高原的水土流失区和近16.5万km2以风蚀为主的沙漠化土地。本文分析若干典型区为案例, 从人口和资源的关系入手, 认识半干旱地区近年来引起环境退化的内在动因。当前半干旱地区入口、土地、环境之间不协调状况是十分值得注意的。现有土地对人口支持能力已处于临界限度; 现有的经营水平上, 土地资源难以支持现有的人口, 就成为这里土地退化的主要原因。退化后土地供应力的降低导致对土地压力的再度加大, 引起更大的环境退化, 这就构成沙漠化土地在该区加剧发展的内在动因。消除引起沙漠化的内在动因, 摆脱对环境压力的危机状态, 在目前最根本的出路在于有计划控制人口增长速度, 降低农业人口的比重和提高土地潜在生产力。但是只要认真采取对策, 人口、资源、环境协调发展的前景是可以达到的。

Abstract: There exists serious problem of environmental degradation in China's semiarid zone (between the two isohyets of 250 and 450 mm). As many as 540, 000 km2 of loess plateau suffering from water loss and soil erosion and nearly 165, 000 km2 of desertified land with wind erosion as its main aspect distribute in this region. Taking several typical areas as cases and starting from the relation of population and resources, this paper analysed the internal dynamic causes of environmental degradation occurred at recent years in semiarid zone. At present the incongruous condition of the population, land and environment is worth notice. The support ability of existing land to population has been in a critical pointo The land resources cannot support the existing population under the present management level, constituting the main cause of land desertification. The decreasing supply ability of degraded land leads to further increasing pressure on land and causes a greater environmental degradation, thus constituting the internal dynamic cause of accelerated development of land desertification in this region. At present the fundamental way out for eliminating the internal dynamic cause led to desertification and ridding of crisis state of environment lies in the facts that effectively control the population birth rate, decrease the proportion of agricultural population and enhance potential land productivity. As long as adopt suitable strategies the harmonious development of population, resources and environment could be reached.