Research On The Environmental Capacity Of Qingzhang River

Along with the speeding up of industrialization and urbanization, the amount of water pollutant emissions is increasing, and the quality of rivers is decreasing. In order to make full use of self purification function of rivers, and achieve sustainably exploitation of water resources, it is imperative to check and ratify and total load allocation of water environment capacity of river pollutants. Research on the water environment capacity and its allocation can figure out the maximum loads of river pollutants under the circumstance that without damage water quality of the river, which can provide basic principles for river environment management and pollution abatement.This paper takes the Qingzhang River in Jinzhong City as the researching object, on the basis of the conclusion of previous researches, and according to each reach’s using function and water quality, the researching river reach is divided into 7 functional areas. Water quality and hydrologic monitoring on 13 typical sections in Qingzhang River are conducted. Based on that, this paper chooses corresponding water quality standard, and applies Single Factor Index Method to evaluate water quality of the river; the results show that, there are 3 sections exceeded the standard among 13 sections.This paper investigates 46 industrial pollution sources, 2 urban pollution sources, 26 scale livestock and poultry breeding pollution sources, 18 rural pollution sources, 18 farmland runoff pollution sources, and 2 urban runoff pollution sources, and investigates the distribution of pollution sources, amount of pollutant emissions and pollutants into the river. According to water environment functional areas and corresponding water quality objectives of the researching river reach, via connecting sewage outfalls into rivers and land pollution sources, it is as basis and foundations for calculation of water environmental capacity. Through classification survey on Relationship between land and water pollution source and discharge of water pollutants, this paper Establishes relationships between sources and input response of river water quality; Using one-dimensional model, and trough model forward simulation, it computes COD and Ammonia Nitrogen environmental capacity of different functional areas of the Qingzhang River in Jinzhong City, and gets an ideal water environmental capacity in accordance with local water quality objectives requirement. To feedback, adjustment and calibration the Results of Capacity calculation, it can give assimilation capacity of each controlling units, and allocates available environment capacity to each functional areas.At the end, the paper propose suggestions about enhance relocation and management of pollution source, and reclaimed water reuse. Each reach can use the settled environmental capacity to provide scientific basis and technical platform for traditional pollution source management and the approval of new, modified, expanded project management, and can laying foundations for total discharge of pollutants decomposition and discharge permit issued, provide basis for constitute various professional planning of water environment protection.