地貌临界说是本世纪七十年代初根据系统论提出的地貌学新概念。它是“突变论”与“渐变论”之间的仲裁,具有较深的哲理和科学内函,代表着当代地貌学的一个发展方向。本文就治河及护岸中涉及的地貌临界问题谈些管见,供读者批评指正。一、地貌临界概念所谓临界(Threshold),有门坎、阈或阀的含义,而地貌临界是指地貌系统由稳定变为突然不稳定的突变点及其发生的空间和时间。根据导致地貌系统突变的控制条件的属性,地貌临界可以区分为由地貌系统外部 The theory of geomorphology is a new concept of geomorphology proposed by system theory in the seventies of this century. It is the arbitration between “mutation theory” and “gradualism theory”. It has a deep philosophical and scientific internal letter and represents a development direction of contemporary geomorphology. This article talks about the critical issues of geomorphology involved in river regulation and revetment, and criticizes them for criticism. First, the critical concept of landforms The so-called threshold (Threshold), threshold, threshold or valve meaning, and geomorphological critical refers to the terrain system from stable to suddenly unstable point of mutation and the space and time. Depending on the nature of the control conditions that lead to the abrupt change of the geomorphic system,