Study On The Pollutant Carrying Capacity Of Shaxi Stream Minjiang Riverof Fujian

There are a lot of rivers in Fujian Province, some of them are highly developed and utilized. Some major rivers such as Minjiang River and Jiulongjiang River have the cascade development of water resources. Shaxi stream is one of the main stream of the three major tributaries of Minjiang River, which is the largest river in Fujian Province. There are eight reservoirs have been built in the main stream of Shaxi stream which is the most typical cascade rivers in Fujian Province. It is very important to definite quantitative determination the unnatural conditions of the pollutant carrying capacity of rivers in order to manage the reservoirs and water resources scientifically and rationally and to reduce pollution of rivers to ensure downstream water quality keeping stability and to ensure the continued normal waters playing a crucial function.This study collected and investigated the water quality of the basin and the outfall information and then used the indoor experiments and water quality degradation model parameters simultaneously to obtain the coefficients of the water quality degradation. According to the rate of 50%, 75%, 90% of the minimum monthly average flow design flow, we analyzed the operating characteristics of the cascade hydropower stations in Shaxi stream and established the responding relationship between the pollution sources and the water quality of the water intake area and the administrative section, then achieved the following main results:1. Research section from the Ansha Reservoir dam to the Shaxikou river where total COD pollutant carrying capacity was 66619.5 t / a and the concentration of NH3-N was 4659.0 t / a.2. The total remaining pollutant carrying capacity of the research section that the concentration of COD was 37256.8 t / a and the concentration of NH3-N was 849.4 t / a. Regional function of the water, the Sanming area of industrial water pollutants into the river has been the status quo more than the water pollutant carrying capacity, and should reduce the volume of pollutants into the river COD for 2699.4 t / a, NH3-N to 1183.8 t / a, the other functional areas of river remain have a pollutant carrying capacity to some extent.3. The controlling of pollutant sources in response to the relationship between cross-section results showed that: (1) Ansha emissions sources of the town was more sensitive to al-duck Lake Reservoir water quality control sections; (2) a comprehensive pollutant source of Yong'an City had the greatest impact on Yongan / SanMing urban water sector control section; (3) The biological pollutant source from HuiTian Company and the plastic pollutant source from HongMing Company had similar effects on the water quality of the intake control cross-section in Sanming water plant. (4) Edward Green pollutant source was most sensitive to the Sanming / Nanping City sector water quality control sections.