Water Quality Evaluation of Songhua River and Water Environment Capacity Calculation in Harbin

On basis of monitoring data from 2001 to 2005 of Songhua River\´s dry season in Harbin by Harbin Environmental Protection Administration, this paper applicated Radial Basis Function Neural Network (RBFNN) model based on Hybrid Hierarchy Genetic Algorithm (HHGA)and taked water quality evalucation of six monitoring sections: Zhushun tun, Ashe internal estuary, lower Ashe estuary, Hulan internal estuary, lower Hulan estuary and High Dingzi mountain. The result showed that the model was reasonable and feasible, which didn\´t merely determine the structure and parameters of RBFNN conveniently and precisely, but had practical conclusion. The water quality of six monitoring sections was respectively Pi , inferior V, IV, inferior V, IV, IV by inoculating. Zhushun tun was only accord with water quality target. The section from Zhushun tun and Ashe internal estuary was severe pollution zone. The monitoring and evaluation of water environment can provide the scientific basis for water resources\´ management and the calculation of water environmental capacity. According to water environmental function zones and water quality target, based on river hydrological characteristics, the distribution of blowdown part to rivers and other factors, by using the software of "river water environmental capacity analysis system" to calculate water environmental capacity of function zones , the calculation results showed Songhua river \´s main stream and the tributary Hulan river had environmental capacity, Ashe river had no environmental capacity. Laid the foundation and proposed measuring basis for total amount reduction in 2010 .