Taking Songliao Plain as an example, the proposition that strong stress makes a fragile environment into catastrophe is demonstrated for the first time.

Based on lots of data, from the view of environment and hydrology, this paper analyzes the hydrologic effect of the woods system, and demonstrates the necessity, probability and availability of the green project in the plain under the condition of fragile environment, then gives a way for implementation and puts forward problems.

This paperapplied the basic theory and method of landscape ecology to analyze the landscape pattern of fragile environment in this area.

Nanjing Xuanwu Tunnel,a subaqueous highway tunnel in the centre of the city is a typical geoengineering project in vulnerable environment.

This paper, from four aspects of population capacity, growing amount of communities and their biomass, eco-environmental sensitivity, and capacity resisting natural disasters, expounds the basic features of eco-environmental fragilities in Guizhou Karst mountain region and analyzes the causes and mechanism of eco-environmental fragility and suggests corresp.

This paper, taking 42 counties (or cities) in the Wujiang Basin as examples, deals with the main principles of rcgionalization of the eco-environmental fragility in karst area, discusses and quantifies the index of the fragility regionalization.

(1) It is main reason of causing ecological environment deteriorating and ecosystem degenerating,that fragile ecological environment crosses resources concentrating exploitation.

There are many types of fragile ecological environments with fast evolement in many regions in China.

The assessment indexes of fragile ecological environment have been established based on analyses of natural and human factors and the calculating formula to evaluating the grades of fragile ecological environment were instituted: p= Σ n-7i=1f i·w i.