Dynamic Mechanisms for Evolution of Mountain Rural Settlements and Soil Conservation in Upper Yangtze River Basin

摘要

This paper presents the logic relationship between rural settlement reconstruction and soil conservation in the Upper Yangtze River. Firstly, by introducing the concepts of "flow" and "intercepted flow", we probe into the dynamic mechanism on interaction between ecological and environmental system, and then point out that the "intercepting sites" are physical conditions for establishment of human settlements in mountains. Secondly, by using ecological theories, "flow", "source", and "sink", materialcycle and energy flow in mountains have been discussed. Thirdly, according to dissipative structure theory and thermodynamic laws, a hypothesis has been proposed that "entropy flow" is a dynamic force for settlement evolution. Finally, it is argued thata project for soil conservation is set to control and utilize flows so rural settlements can be supported and farmers' life improved.