Research On Total Amount Control Method And Application In Bay

Total amount control has become an important measure to prevent water pollution. It is the important basis for implementing the water resources objectives management,as well as water resources protection planning. Research on total amount control in the bay region is significant for protecting marine environment, coordinating economic development and marine resource exploitation,and realizing the sustainable development of marine economy. In view of the insufficient study of total amount control on non-point sources and nitrogen and phosphorus the paper researches into the method of total amount control in bay. The main contents and research results are as follows:1.A three-dimensional water quality model coupled with ECOM-si hydrodynamic model was developed based on the eutrophic module of WASP5,which includes of eight state variables. The model is calibrated and verified with the observation data. The above work lays the foundation for the assimilative capacity calculation of non-conservative such as nitrogen and phosphorus. at the same time, this provides a scientific basis for environmental planning and management.2.A model frame of environmental capacity calculation and waste load allocation is modified in this paper. Nitrogen and phosphorous tend to be treated as conservative material in previous study and non-point pollution source is considered inadequately in waste load allocation. For solving the problem a method is brought forward by including the influence of biochemical process and the contribution of non-point pollution source in water quality constraint equation in this paper.3.The water quality and the pollution status is quantitatively estimated by adopting subjection degree weighted average method, fuzzy comprehensive evaluation model and equiscalar waste load method. The evaluations show that water quality generally fall in second level. The eutrophic degree is higher in coastal area and lower in southern and central area. Riverin input is the primary pollution source, which ration of equiscalar waste load reach 88.42%. The main contaminations are COD, ammonia, and total phosphate, their equiscalar waste load ration are 34.43%,33.14%,and 29.95% respectively.4.The model was used to simulate the spatial distribution and the temporal variation of ammonia, nitrate and phosphorus for period of May 2005 to May 2006 in Jiaozhou Bay. In addition the budgets of nutrients are roughly estimated. We draw the following conclusions by simulation. Under the influence of river discharges, the concentrations of nutrient were higher in the east, northeast of the bay near river mouths, where a north-south pollution belt comes into being. The phytoplankton growth has a direct effect on nutrient concentration. The nutrient seasonal variation is characterized by consumption in spring and summer, increase in autumn and accumulation in winter. River discharge is the biggest source of ammonia and phosphorus. In nutrient cycle phytoplankton plays an important role, photosynthesis is the biggest sink for ammonia and phosphorus in Jiaozhou Bay. Because of phytoplankton preference for ammonia the amount of photosynthesis consuming nitrate is small,while transport act as the most important role in reducing the concentration of nitrate. In contrast to ammonia and phosphorus nitrification is the first magnitude source. After a whole year circulation there is a net increase of ammonia, nitrate and phosphorus in Jiaozhou Bay, with the value of 438t, 116t, and 138t respectively.5.The model was used to simulate the spatial distribution and the temporal variation of dissolved oxygen and COD. The simulation results coincide with the observed data. The DO concentration distribution of is different to nutrient. The DO distribution is higher in outer bay and center bay. The DO concentration is higher in winter and lower in summer and autumn, which fluctuates in a small range during one year.6.The model was also used to simulate the temporal variation of phytoplankton and primary productivity during the period from May 2005 to May 2006. From the perspective of model the structure of primary productivity is discussed and f ration is estimated. The results indicate that phytoplankton biomass shows a bimodal pattern, which exhibited two peaks in summer and spring respectively. The simulated primary productivity is highest in summer, lower in spring and autumn, and lowest in winter. Simulation of phytoplankton biomass and primary productivity is in agreement with the observations. F ration estimated in this paper is approximately 0.61, which indicates the higher new primary productivity in Jiaozhou bay and demonstrates 15N isotope tracer method based on the nitrogen demarcation is likely to underestimate the new productivity Level in costal area.7.The influence of riverin flux variation to the ecosystem is discussed in Jiaozhou Bay. This influence is distinct in the east, while it is relatively faint in the south of the Bay. Phytoplankton is most sensitive to the change of land-source pollutant input, while dissolved oxygen is relatively beef-witted. If pollutant input from river reduces 75%, the phytoplankton biomass would reduced 79.8%, while the dissolved oxygen concentration would reduce 3.5% near the mouth of Dagu River.8.The contribution of Non-point source pollution and the influence of biochemical process to water quality in Jiaozhou bay are simulated. Then an environmental capacity computation and waste load optimization allocation model is established. Based on the model, the environmental capacities of COD, inorganic nitrogen and phosphorous are 84601t/a, 5085.3t/a and 633.3t/a respectively in Jiaozhou Bay. The Environmental capacity is assigned to the main pollutant sources, and then the pollutant discharge reduction plan of some pollutant source is brought forward based on the prediction of pollutant flux in 2010. The environmental capacity of nutrientes is only residual near the Tuandao area because of its relative strong water exchange. That is to say, the pollutant discharges need to be reduced in other pollutant sources. For example, the pollutant discharge reduction rates of Moshui river and Loushan river located in the northeast of the Bay is over 85%, and that of Dagu river and Licun river is beyond 36%, however, that of Haibo river and Qianwan are relatively lower.At the end, the research work is summarized and a perspective on the future research is made.