The Application Of GIS And Projection Pursuit Model On Water Quality Assessment

With the development of society, human beings continue to influence and transform the surrounding of the environment, thus causing serious damage and pollution, inch by inch, the growing anomalies of climate, greenhouse effect, destruction of vegetation, shortage of water resources and other global environmental problems, which become the main factors to restrict the development of social and economic. The destruction and pollution of water environment is an important part of environmental problems. Therefore, the protection of water environment has become an important work to develop and utilize the water resources.Water quality monitoring and assessment is the main contents of water environment management. We can understand the past, the present and the future development trend of the water environment quality as well as its variation law through the water quality assessment. And also, the water quality assessment provides a scientific basis to formulate the integrated control measures and programs, and to establish the national or local environmental standards and regulations.Quality assessment method is the research focus of this article, the paper introduces the application of GIS theory and the projection pursuit model in the field of water quality assessment, and the research includes the following five aspects.(1) The research progress of water quality assessment theory at home and abroad was reviewed detailedly, the basic theory of the water quality monitoring and assessment was described, and the development tendency of the water quality assessment methods was forecasted.(2) The theory of projection pursuit model was described and the traditional projection pursuit model was improved. The accuracy and speed of water quality assessment has been improved by the modified model.(3) Spatial statistical analysis has been introduced to excavate the correlation between the regional water quality, of which make spatial interpolation and space-time characteristics analysis according to the water quality monitoring data in time and space as well as combining with the geostatistics.(4) GIS theory and projection pursuit model were integrated in order to evaluate the regional water quality conditions comprehensively, display the assessment results visually, and make the overall analysis of the water quality development tendency. The application of GIS in the environmental field has been deepened by mean of the combination of GIS theory and water quality assessment model.(5) The decision support system of water environmental information management was developed to achieve the basic function of water environment information management, the above-mentioned theory has been used in the system to evaluate the regional water quality conditions comprehensively, analyse the development trend of the water quality, and thoroughly excavate the useful information of the water environment data.