坡面侵蚀中径流含沙量测量方法研究与展望

Evaluating the measuring methods to sediment concentration in the runoff of slope erosion

土壤侵蚀中的径流含沙量是衡量坡地水土流失的重要参数之一 ,只有合理测量坡地径流中的含沙量才能为水土保持提供有利的依据 ,同时为验证土壤侵蚀预报模型提供基本参数。本文从测量原理出发 ,对含沙量各种测量方法的适用环境、测量精度及其局限性进行了比较全面的分析 ,重点研究了坡面径流含沙量的测量方法。研究结果表明目前测量含沙量的方法在坡面侵蚀动态水流含沙量的测量中存在只能静态测量的问题。目前电解质脉冲法在测量坡面薄层水流流速中做出了有益的探索 ,研究发现水流速度、泥沙的弥散系数与含沙量之间存在着相关关系 。

Sediment concentration in the runoff is an important parameter to evaluate the soil and water loss of the slope.Proper measurement of the concentration can provide not only the basis for water and soil conservation,but the data for the model calibration and verification as well. From the point view of measurement principle,this paper analyzed the suitable condition, measurement accuracy, and limitation of different measuring methods,especially the measuring method for sediment concentration of runoff in the slope erosion.Results show that present methods can be used only for the static state measurement.Based on the fact that the electrolyte pulse method can measure the velocity of moving runoff in the slope erosion and the sediment concentration has a good relationship with flow velocity and sediment dispersion coefficient,the electrolyte pulse method could make it possible to reach the dynamic measurement of sediment concentration of runoff in the slope erosion.