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一、草地荒漠化现状 草地荒漠化是土地荒漠化主要类型之一。根据中国荒漠化监测中心1997年的统计表明,全国荒漠化草地1052374平方公里,占草地面积的56.7％。 草地荒漠化主要表现为草地植物群落盖度明显减低,单位面积产草量下降,可食性草类减少,有害草类增加,草场等级下降。裸露地表比例增加,为风力侵蚀创造了条件;而风蚀又加剧了草地荒漠化进程,形成恶性循环,继而发展为流动沙地。 我国草地荒漠化程度与人口密度和牲畜
I. Current Situation of Grassland Desertification Grassland desertification is one of the major types of land desertification. According to statistics released by China Desertification Monitoring Center in 1997, 1,052,374 square kilometers of desertified grassland nationwide accounted for 56.7% of the total area of grassland. Grassland desertification is mainly manifested as significantly reduced coverage of grassland plant communities, decreased grass yield per unit area, decreased edible grass species, increased harmful grass species and decreased pasture grading. The increase in the proportion of bare land surface created the conditions for wind erosion, which further exacerbated the process of grassland desertification and formed a vicious circle, which then developed into a mobile sand land. Grassland Desertification, Population Density and Livestock in China