黄土坡面侵蚀过程实验研究Ⅰ．产流产沙过程

Experimental Study on Erosion Process Over Loess SlopesⅠ. Surface flow and sediment transport

黄土坡地坡面侵蚀过程包括降雨过程中的产流产沙过程以及相应的坡面形态变化过程，该文主要研究产流产沙过程。在对国内外已有同类成果分析的基础上，为了弥补现有成果的一些不足之处，设计了室内黄土坡面侵蚀模拟实验。实验分１０个组次对产流、渗流、产沙、沟道发育、沟与坡的侵蚀过程及其坡蚀量、沟蚀量、侵蚀过程中的微地貌现象直至坡形变化进行了详细测量与观察，获得了大量实测数据。关于坡面形态变化的讨论将在后文②展开。本文及后文￣［１］中论述的实验结果不仅初步揭示了黄土坡面侵蚀过程中上述要素的变化机理，而且也为今后在这方面进行定量化研究提供了精度较高的实测资料。

On the basis of an overvicw of the existing works ,key problems are raised and the ex-periments on loess erosion over slopes are specially designed so that some aspects of the erosion pro-cess and slope variations can be studied in greater details. Among them the proress of surface flowand sediment transport is discuswesed in the present paper, and the latter is further dealt in the com-panion paper. Numerous data have been obtained by measurements and observations on the issauessuch as rainfall splash, runoff, infiltration, sediment transport,rill evolution, erosion process of rilland inter-rill areas and micro-geomorphic phenomena etc.The principle laws of infiltration as wellas the variation of surface flow,sediment concentration and the sediment grain-size daring the rain-fall are diseussed based on the data. The tendency of various processes to the equilibrium conditionstrongly suggests that the slope profiles in the steady state are largly deternned by the characters-tics of the″proress″。