论文部分内容阅读
在一般情况下,沟道切割密度愈大,水土流失愈严重。因此,沟道切割密度是反映土壤侵蚀强度的一项重要指标。在土壤侵蚀区划及土壤侵蚀规律的研究中,科学工作者十分重视这一数量指标。但是如何量算沟道切割密度?如何选定量算样区?选择多大的沟道小流域作为量算样区比较好?以及量算样区是选在上游好,还是中游或下游好等一系列问题,目前都还缺乏经验,如果量算样区选择不当,所得结果就不能代表当地的实际情况。我们从1980年到1982年,通过陕北杏子河流域沟道切割密度的量算,取得大量的数据,并进行统计分析,初步得出全流域上、中、下游沟道切割密度分布规律及流域面积与切割密度的相关关系,可作为量算沟道切割密度时选定量算样区的参考。
Under normal circumstances, the greater the channel cutting density, soil erosion more serious. Therefore, the channel density is an important indicator of soil erosion intensity. In the study of the rules of soil erosion division and soil erosion, scientists attach great importance to this quantitative index. But how to measure the channel cutting density? How to choose the sample area? Choose how small the channel watershed as the sample area is better? And the sample area is selected in the upper reaches of the good, or the middle reaches or downstream, a series of good The problems are still inexperienced at present. If the measurement sample area is not properly selected, the result can not represent the actual situation on the ground. From 1980 to 1982, we obtained a large amount of data through the calculation of the channel cutting density in Xingzihe basin, northern Shaanxi, and conducted statistical analysis. The distribution of the cutting density at the upper, middle and lower reaches of the whole basin and the basin The relationship between the area and the cutting density can be used as a reference for measuring the sample area when measuring the channel cutting density.