The Study Of Water Eutrophication Simulation And Assessment On The Effects Of Power Plant Thermal Effluent In Xiangshan Bay

In recently years, as the rapid development of exploiting the marine resources, Xiangshan Bay confronts the highest upsurge for its exploitation. The thermal effluent from coastal factories affects the environment of the water ecosystems nearby directly, threatening the marine environment of Xiangshan Bay heavily. Those factories are Guohua Power Plant, Datang Power Plant, Yinglongshan Power Plant, Chunxiao Oil & Gas Field, etc. As Xiangshan Bay is a long narrow harbor of semienclosed shape, it has weak hydrodynamic conditions, therefore, it takes the harbor a relatively long period to pursue water exchange with the outer sea (nearly 3 monthes).The influx of thermal effluent accelerates the eutrophication form in the water system.To expbre the effects of thermal effluent onto the eutrophication condition in Xiangshan Bay, through the first-phase survey and research, we select exuberant season of biobgy growth (2010,10) to conduct the encbsure experiment. Make sure the water sites for encbsure experiment, and choose water areas with proper depth, ocean current and convenient traffic. According to the above factor, we set three groups of encbsure equipments which is put of different distances from the outlet of the power plant, representing water areas of different temperature levels. Ml represents obvious elevated area, M2 represents weak elevated area, and the third group is set outside the areas with aberrant tempereature to be a site for contrast. The experiment lasts half a month focuses on the water systems in and outside the encbsure equipments.This article analyses the effects of the thermal effluent in Xiangshan Bay on water eutrophication by the combination of using nutrients migration and transformation model which is based on the data in the encbsure equipment and eutrophication assessment on the grounds of the spot monitoring data collected outside the encbsure equipment. The former analyses the effects by eutrophication assessment on the basis of the spot monitoring data outside the encbsure equipments, namely, this article covers two parts- simulation and appraisal, the latter simulates temperature's effects on water eutrophication on mechanism; however, from the standpoint of empirical research.On the basis of the data monitored from the sea areas near Guohua Power Plant in Xiangshang Bay in year 2010, three different eutrophication assessment methods are utilized for the desired areas (three water areas of three temperature levels), including OSPAR, Nutrition Index (E Value), Potential Eutrophication Assessment and the Carlson trophic state index evaluated and compared four methods of evaluation results, obtained eutrophication effects of temperature on the findings of the final evaluation for the four summarizes the results obtained in different temperature zones, the degree of difference between eutrophication, namely thermal discharge on the impact of eutrophication, the results of the table was the most serious eutrophication temperature zone, the weak temperature zone, folbwed by the lightest control area, indicating that the temperature of water exacerbated the eutrophication of receiving water.Nutrients migration-transformation dynamic model adapted to marine encbsure planktonic ecosystem is built on the main line of nitrogen and phosphorus nutrients cycles. The values of relative parameters are confirmed using the data of the encbsure ecosystem experiment from one temperature level area among the three areas collected in Xiangshan Bay in 2010,10, to simulate in the model Also, these parameters are used to simulate the processes of nitrogen and phosphorus nutrients biochemical migration-transformation in the three areas of different temperature levels, and then reach conclusion about the effects of thermal effluent on nitrogen and phosphorus nutrients migration-transformation within encbsure planktonic ecosystem, And try to analysis the relation between the increased temperature and water level of the receiving mechanism of eutrophication from the dissolved oxygen, nutrient concentrations, phytoplankton, zooplankton and other impact angles.