Earth Surface Processes
FENG Yan, HE Da-ming, YANG Li-ping
River health has become one of hot topics on water issues in recent decades,and the corresponding evaluation index systems are becoming the objectives of river basin management in some countries and regions in the world.Most of the existing evaluation index systems on river health have not been widely used due to their complex and more professional indexes involved.The authors consider that some major evaluation/important indicators can be selected to show the status and developing tendency of river health.Around 150 research papers,documents and standards on river/river system health in 1972-2010 were reviewed,and 45 evaluation systems with 902 indicators were obtained.According to the river characteristics described in this study,the indicators were identified into four types: habitat physical index,water environmental index,biotic index and water utilization index.By the statistical method,the adopted number and the adopted rate for each indicator were calculated,and 26 indicators with higher adopted rate which can show the characteristics of river/river system from various aspects were selected as the candidates.Then,in order to make further selection of the more important,more universal,easily quantized and obtained ones from the above candidates,the methods of hierarchy analysis and correlation analysis of the indicators were used based on the conclusions of the relevant researches and the relevant concepts,and some of the candidates were incorporated into one if the means or characters of them were similar or overlapped or covered each other.Finally,8 indicators were determined as the major indicators for evaluating river health condition,which were: coverage rate of riparian vegetation,the changes of wetland extent,river continuity,the changing rate of water flow,the ratio of reaching water quality standard,fish index of biotic integrity,the ratio of water utilization and the coverage of natural vegetation in the watershed.
