细沟侵蚀是黄土坡面重要的侵蚀过程和形式,细沟水流分离是细沟侵蚀的初始阶段,而水流分离能力的大小直接决定水流带走土壤的多少和产生侵蚀的强烈程度。阐明细沟水流分离能力随坡度和流量的变化特征可以深入揭示细沟侵蚀过程机理,为建立黄土坡面细沟侵蚀过程模型奠定重要基础。采用细沟水槽试验方法对黄土坡面细沟水流分离能力变化特征进行研究。结果表明:不同坡度或不同流量下,细沟水流分离能力随流量或坡度的增加而增大,可用线性方程和幂函数方程很好地描述;细沟水流分离能力随流量及坡度变化的因子模型为二元幂函数方程:Dc=61551.72S0.762741-136.248/s2Q1.850263-0.000003/Q,试验条件下流量对细沟水流分离能力的影响大于坡度的影响。
Rill erosion is an important erosion process and form on loess hillslope. Rill flow detachment is the initial stage of rill erosion. The large of the flow detachment capacity can directly determine how much soil is taken by water and result in erosion intensity. To clarify detachment capacity of rill flow may be to reveal rill erosion process mechanism on slope and lay an important foundation on the establishment process-based mod- el. In the paper, the variation characteristics of detachment capacity of rill flow detachment capacity were studied by a flume. Results showed that: Under different flow discharges or different slopes, soil detachment capacity of rill flow increased with increasing slope and discharges. They could be well separately described by linear functions and power functions. The factor model of relationship between soil detachment capacity of rill flow and the flow discharges and slopes was a binary power function Dc=61551.72S0.762741-136.248/s2Q1.850263-0.000003/Q Flow discharge had greater influence on soil detachment capacity of rill flow than slope.