| Water is essential to the progress of human civilization and social development and natural resources,and people can directly use the fresh water accounts for only 2.5% of global water resources,with the increase of water consumption from all over the world,the increasingly prominent contradiction between supply and demand,how to reasonable development of the stock of limited water resources,become a realistic problem urgently to be solved.The emergence of the reservoir is in order to satisfy the human demand for scientific and effective allocation and utilization of water resources.In water shortage in north China province,most of the reservoir not only has the effect of flood peak,the irrigation farmland,but also become an important water source of drinking water,shoulders on the responsibility for residents to provide water,its water quality is good or not will directly affect the residents’ drinking water safety.At present,most of the research hotspots for reservoir water quality are concentrated on nitrogen,phosphorus and other nutrients,and the effects of suspended sediment are less considered.Suspended sediment as a hotbed and carrier of water pollutants exacerbates the transport and diffusion of pollutantsto a certain extent,which has become a factor that can not be ignored in the study of water quality problems.Therefore,it is necessary to analyze the law of influence of suspended sediment on the water quality of reservoir.Based on the project of Shanxi Natural Science Foundation,in constructing a hydrodynamic model on the basis of,according to the real situation of water environment of fenhe reservoir,select the appropriate impact factor,set up in line with the actual reservoir sediment transport and eutrophication water quality model,and the three associated coupling,hydrodynamic,sediment transport,eventually establish reservoir eutrophication of water quality coupling model,typical reservoir in the north drought area of fenhe reservoir for the study of the carrier,set different hydrodynamic and water quality simulation,quantitative research and analysis into the fenhe reservoir high content of suspended sediment in the reservoir water quality change,through the contrast analysis of water containing sand and the water containing sand different influence of each water quality index,revealed the influence law of suspended sediment of fenhe reservoir water quality.and the release amount and contribution rate of bottom sediment were calculated,which provided a technical support for the scientific use of water resources of Fenhe Reservoir and control of reservoir area pollution.The research results are of theoretical significance as well as use value.The research results of the paper are mainly reflected in the following aspects:(1)In accordance with the topographical features of the fenhe reservoir,combined with the feature of the deteriorating water environment and the characteristics of the sediment,on the basis of the hydrodynamic model building,fully considering the influence law of sediment on water quality,explore a research in the north drought area reservoir sediment pollutant effect on new technology method system.(2)Overall consideration of various factors that influence the reservoir eutrophication process of planktonic animals and plants to grow complex behavior and transport of pollutants diffusion process and suspended sediment transport process integrated together,based on reservoir water dynamic model,set up in accordance with the fenhe reservoir sex good hydrodynamic,sediment transport,the reservoir eutrophication(water quality)associated coupling model.(3)Adopted digital elevation model and satellite remote sensing and global positioning system(GPS)and other methods to fenhe reservoir’s geographical location and the reservoir along the boundaries are analyzed,and the combination of fenhe reservoir landform has carried on the omni-directional determine,in the generated after the simulation range for grid,before completing the model building process of data preprocessing.Based on the definite conditions of the model,four indexes of TN,TP,chlorophyll a and dissolved oxygen were selected for the simulation analysis.Combined with the distribution law of suspended sediment,the influence of sandy and non-sandywater on the water quality in the reservoir area was compared and analyzed.(4)The results of hydrodynamic simulation showed that the change of inlet and outlet flow has little effect on the morphology of flow field of Fenhe Reservoir,wind is the main driving force to promote the flow of water in the reservoir,and the wind-driven flow is the main form of flow in the reservoir,in which the wind speed determines the water flow speed,and the wind direction determines the form of water circulation.(5)Eutrophication(quality)of the simulation study results show that the suspended sediment of the reservoir water quality impact does more harm than good.On the one hand,as the suspended sediment into in great quantities,can cause water turbidity increased,resulting in attenuation of water radiation so that the light transmission of water is reduced,thus hindering plant photosynthesis.On the other hand,pollutants are removed through adsorption degradation,which purifies the water quality and reduces water pollution.Suspended sediment has little effect on the distribution of chlorophyll a and dissolved oxygen concentration but obvious effect on the removal of nitrogen and phosphorus.The calculation results of sediment release indicate that the contribution rate of phosphorus is large,and pollution control measures should be carried out to reduce the sediment content. |
PDF Full Text Request