Abstract: The concept of ecosystem integrity was proposed to protect the biological and ecological resources against the interference of human activities, and has being turned into a basis of public policy and decision making in environmental issues. Many of the ecosystem management and planning activities are taking ecosystem integrity as the principle and goal. In this paper, a hierarchical ecosystem framework of the headwaters of Yangtze River was established, and an indices system for the assessment of the ecosystem integrity of the headwaters was developed. According to the assessment results of ecosystem integrity, the headwaters of Yangtze River could be divided into three units, i. e. , ecologically good, ecologically vulnerable, and to be ecologically restored with priority.

Key words: Arid desert region, Artificial plant community, Succession pattern, Ecological mechanism