Study On Management System Of Poyang Lake Water Environment Based On Open Source GIS

With the rapid development of open source GIS technology, open source GIS softwares are popular with experts in various fields, because of their maturing of the system functions,open source completely and low cost, and they are being widely used in environmental monitoring, environmental assessment, hazard assessment, regional ecological planning, land management and other fields. In one world, open source GIS softwares are effective tools for many departments to make decisions.In this paper, the author takes the Poyang Lake as the research object. Based on full knowledge of Open source GIS technology development and the integration of GIS and Water Research model at home and abroad, the author proposed the solution of Poyang Lake water environment management based on open source GIS technology, the purpose of which is to reduce system construction costs and accelerate the process of water environment management informationization.Firstly, this paper introduces the current status of GIS application in water environment management at home and abroad, analyzes and summarizes the shortcomings of the current application and the direction of future development, and illustrates the purpose and meanings of this study. After expounded the theory of open source GIS technology and contrasted open source GIS softwares, this thesis determined the open source GIS platforms that will be used. Besides, considering the requirement of water environment management, the author analyzed the system structure and the function module of the system, and the author determined the system's final goal. Based on the system analysis, this thesis completes the detailed design of system's database and the functions of each subsystem. Secondly, aiming at Poyang Lake with great and rapid stage fluctuation, the author uses two-dimensional shallow water equations and pollutant transport equations to develop the coupled two-dimensional hydrodynamic and pollutant transport model. The hydrodynamic model is calibrated by the water regime of the year 1998. Based on the calibrated hydraulic parameters, the hydrodynamic and water quality (CODMn and ammonia) of the year 2008 are simulated by the proposed model. And the author uses the data of measured water stage, CODMn, ammonia and CBERS data to validate the results of computation in time and space. The results indicate that the model can do well in model the flows dynamic and the pollutant transport in this kind of the lake. Finally, using open source GIS platform and C#,fortran pogramming language, the author completed the integration of the water environment model and the open source GIS systems. The system achieves the functions of the data retrieval, data updating, statistical analysis, hydrodynamic and water quality prediction, result output, thematic map production, information dissemination and so on.This thesis does some tries and discussions about the open source GIS application in water environment management, and the preliminary results show that the system can meet the needs of the Poyang Lake water environment management, and it has a strong practical value.