半干旱地区水土流失因素的定量分析——以甘肃中部半干旱地区祖历河流域为例

本文从地貌演化角度,探讨了土壤侵蚀过程的动力学机理。认为土壤侵蚀过程受控于内力和外力两种营力过程及人类活动过程的共同作用。在内力相对稳定的时期内,土壤侵蚀过程主要依靠外力过程和人类活动过程共同完成;水力侵蚀是半干旱地区土壤侵蚀的主要方式之一,影响土壤侵蚀的外力因素主要是流量与降水。笔者以甘肃中部半干旱地区祖历河流域为例,运用灰色系统理论的灰色关联分析方法为手段,研究揭示了输沙量流量与降水指标之间的关系,提出了半干旱地区水土流失过程的产流、产沙函数,由此导出了水土流失因素定量分析的数学模型,并分析了祖历河流域五十年代初期至八十年代中期,人类活动对减水、减沙效益的贡献。

QUANTATIVE FACTOR ANALYSIS OF WATER AND SOIL LOSSES IN SEMI-ARID AREA——With the example of ZuLei river drainage of semi-arid area of central part of Gansu province

This paper analyzes the dynamic mechanism of soil erosion from the viewpoint of geomorphological evolution, regarding that the soil erosion process iscontrolled by three main process: endogenic forces process, exogenic forcesprocess and human activity process.When the endogenic forces are relatively,stable soil erosion process is finished by the exogenic forces process andhuman activity process mainly.Water forces are main exogenic forces of soilerosion of semi-arid area,and runoff is most relative with silt.In this paper,the authors show the relationship between silt, runoff and each rainfall valu-es by the grey relative analysis method with the example of Zulei Riverdrainage of semi-arid area of central part of Gansu province,and give the prod-uctive founction of silt and runoff.The quantative factor analysis models areobtained from the founctions.Finally, We analyze the human activity effectson decrease of silt and runoff of Zulei River drainage of semi-arid area ofcentral part of Gansu province.