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机构地区:[1]太原师范学院,太原030012
出 处:《水土保持研究》2006年第4期256-259,263,共5页Research of Soil and Water Conservation
基 金:国家自然科学基金资助项目(40471033)
摘 要:分析研究了西汉至今两千年来,汾河水库上游人口、耕地的增长过程,结合勘察观测资料,得出以下结论:(1)在AD1892以前,本区土壤侵蚀的动力是自然侵蚀作用,耕地的扩大不是导致土壤侵蚀加剧的原因;(2)整个历史时期直至现代,沟蚀在本区总侵蚀量中占主要成份;(3)19世纪末以来,由于人口激增,开始开垦陡坡地和急坡地,导致土壤侵蚀加剧,但就总体而言,侵蚀量中大部分仍是自然侵蚀即沟蚀,坡地开垦所造成的侵蚀量占第二位。Combined with the investigation materials,the authors studied the population and the farmland increase in the upperreach of Fenhe reservoir in past 2000 years from the Han Dynasty. Some main results are as follows. (1)Bofore AD 1982 the main factor led to soil erosion of this area was physical erosion. And the reason of more serious soil erosion was not farmland extension. (2)In the whole historic time to now,the gully erosion was dominant. (3)From the end of the 19 th centery,the population of this area increased rapidly,so the steep slope began to be farmed,which led to more serious soil erosion,but for the whole,most of erosion was physical erosion and the second erosion was because of the slope farming.
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