元代以来洛川塬区沟谷发育速度和土壤侵蚀强度研究

文章用史料考证和实地考察相结合的方法 ,以陕西洛川旧县古城的兴废为地面解译标志 ,以旧县南沟为研究小流域 ,恢复了元代以来洛川黄土塬区沟谷发育与土壤侵蚀过程。计算出了不同时段南沟的沟谷发育速度、土壤侵蚀强度。通过分析得出元代以来洛川塬区沟谷发育速度、土壤侵蚀强度有加剧的趋势 ,其变化与气候变迁、人类活动关系密切 ;降水量较丰富时沟谷发育、土壤侵蚀较强 ;人为加速侵蚀与自然侵蚀相叠加是近现代洛川塬区沟谷发育、土壤侵蚀剧烈的主要原因。建国后黄土高原水土保持效果显著

Study on the Speed of Gully Development and the Intensity of Soil Erosion Since the Yuan Dynasty

Taking the rise and decline of Jiuxian historical town in Luochuan as a mark to differentiate objects, Nangou Valley in Jiuxian as the researching little drainage basin, this paper renews the process of gully development and soil erosion in Luochuan loess plateau, calculates the speed of gully development and the intensity of soil erosion at different time intervals in Nangou Valley by means of historical documents and on-the-spot investigation .By analysis, the paper draws a conclusion that there has been a accelerating tendency in the speed of gully development and the intensity of soil erosion in Luochuan plateau since the Yuan dynasty ,which is concerned with climatic variations and human activities .In the time when the precipitation was more abundant ,gully development and soil erosion would be more violent. The main reasons why gully development and soil erosion have been intensifying in Luochuan plateau in modern times are that erosions by personal factors integrate with ones by natural factors. Furthermore, the article refers to some good results which our country has achieved in conserving soil and water in the loess plateau since 1949.