Study On Water Environmental Fuzzy Assessment And Capacity In Dan River Valley

Some investigations of the Dan river valley were performed in Jincheng city with the basis of water environmental functional section compartmentalization, such as water system characteristic, hydrology characteristic and pollution sources discharging into the river, et-al. Much of date and relevant materials were collected for this study. Using the basic theory and method of fuzzy mathematics, the membership function and relative membership degree of alternative were bought into the water environment evaluation, and then fuzzy comprehensive evaluation was constructed with matrix analysis means. According to the different water equality infection of various contamination factors, the objective weight was ensured. The evaluation factor sets, evaluation criteria sets, membership function and objective weight sets were established, and then a comprehensive fuzzy assessment for the present water environment of the Dan river valley was conducted, by using the principle of maximum membership function and the principle of weighted average method. The discharging pollutant sources and pollutants of Dan river valley were analyzed thread of above all, in order to maintenance the water equality goal of each environment function functional zoning or to revivify the river s natural function, two calculation models of water environment capacity were putted forward in case of one dimension, the complete mixture model of water environment capacity and the non-linearity attenuation multi-spot model of water environment capacity. The allowable water environment capacity was calculated with the two models, comparing with present total amount of discharging pollutants, the reducing amount of discharging pollutants was also accounted. So the quantities of pollutants discharging into Dan river valley could be controlled and it was helpful to total pollutant control.