坡面水蚀动力因子与土壤剥蚀率灰色关联分析

Grey correlation analysis on relationship between soil detachment rate and hydrodynamic erosion factors

为了确定何种水蚀动力因子能准确地描述径流剥蚀土壤的过程,本文在坡度为3°到30°和流量为2 5L min到6 5L min范围内采用土槽径流冲刷试验,运用灰色关联分析法,系统地研究了坡面水蚀动力因子(流量、单宽径流能耗、水流剪切力、水流功率和单位水流功率)与土壤剥蚀率之间的关联度。结果表明:流量相同时,水流剪切力与土壤剥蚀率关联度最大,呈幂函数关系;坡度相同时,单宽径流能耗与土壤剥蚀率关联度最高,两者呈线性关系。

The correlations between the hydrodynamic factors of slope flow (including the discharge, flow energy consumption per unit width, flow shear stress, stream power and unit stream power) and soil detachment rate are experimentally studied in a flume. The width of the flume is 100 cm, the gradient of the slope is ranging from 3° to 30° and the flow discharge is varied from 2.5 l/min to 6.5 l/min. The result shows that the correlation degree between flow shear stress and soil detachment rate is the highest and the relationship is in a form of power function, when the flow discharge is the same. The correlation degree between flow energy consumption per unit width and soil detachment rate is the highest when the gradient of slope is kept as the same, the relationship is linear.