CAUSES AND MECHANISM OF ECO-ENVIRONMENTAL FRAGILITY AND THEIR COUNTERMEASURES IN KARST MOUNTAIN REGION OF SOUTHWEST, CHINA - Taking Guizhou province as an example

摘要

Guizhou .Guanxi and Yunnan province are located in Southwest China where karst landforms are well-developed and the outcropped area of carbonate rock sums up 54×10~4km~2, It is the largest one of three continuous distributing areas of carbonate rock in the world . According to determination , about 73% of Guizhou's total area and more than 40% of the other's(Guanxi and Yunnan) are also covered by carbonate rock and the contradiction between population and farmland is sharp and its Eco-environment is very fragile , in fact , some features of karst environment of Guizhou have to a great extent affected its social and economic development , Obviously , it is necessary for sustainable development of Guizhou province to realize fragile characteristics and their forming mechanism of karst environment correctly and to put forward corresponding countermeasures.