发生沟蚀(切沟)的地貌临界研究综述

沟蚀研究是土壤侵蚀研究的主要内容之一，地貌临界理论作为地貌学中的重要理论在沟蚀研究中得到了广泛的应用。主要从临界理论在沟蚀研究中的发展过程人手，介绍了国外现有沟蚀临界理论模型研究的主要成果，并指出现有模型的不足，在总结前人工作的基础上，指出了现有临界模型今后的发展方向。

Progress in the Study of Geomorphic Threshold Theory in Channel (gully) Erosion

Geomorphic threshold theory,as one of the most important theories in geomorphology,has been applied in prediction of both ephemeral gully and permanent gully.Gully erosion is one of the essential contents in soil erosion.Starting with the developing history of threshold theory in channel erosion,this paper introduced the principal achievement of threshold theory in channel erosion.Under one given climate and land use,channel incision occurs only when SA~b>t is met,where S is local slope gradient(m/m),A is the drainagebasin area(ha),a is a coefficient and b is and exponent.Both a and b show different values in different environments,which is dependent on the dominant process resulting in channel incisison.Because of the influence of human activities,esp.those of linear landscape elements(e.g.,roads,parcel borders,dead furrows),the actual runoff pattern can be very different from that predicted from topography alone.Therefore,in order to get more account.Despite the diversity of factors in fluencing channel formation,this model has been applied for its simplicity and less input parameters.