Situation Evaluation on River Channel Ecological Water Requirements of Seven Major Basins in China

According to attributes of ecological requirements,evaluation methods of river ecological flow was proposed in terms of and quality.The evaluation methods included resources utilization ratio method,measured runoff method,consumption coefficient method;and the evaluation method was established based on wastewater-runoff ratio factors.The standards for and evaluation were also proposed.Seven major basins of China,including the Songhuajiang River,the Liaohe River,the Haihe River,the Yellow River,the Huaihe River,the Yangtze River,and the Zhujiang River,were studied as examples by using the above methods.The results indicated that if these rivers were evaluated merely from quantity,the ecological flow is lower than the requirements standards in the Haihe River and the Yellow River;however,if these basins were evaluated at the same time of and quality,the ecological flow is higher than the requirement standards only in the Songhuajiang River,the Yangtze River and the Zhujiang River.These showed that actual ecological shortage could be revealed only by evaluation methods on the basis of water quantity and water quality in China.