Systems Analysis Of Water Resource Of Dongting Lake Based On Uncertainty Theory

Dongting Lake is the second freshwater lake of China, and its functions include transportation, aquatic production and environmental improvement, and so on. But, with the development of society and economy, under the double function, human and nature, Dongting Lake came forth many eco-environmental problems such as frequent floods, aquatic environmental and ecosystem deterioration, and so on. It has become the confinement factors to the development of the regional society and economy. Many researches focus on bedload move, ecosystem service function, floods frequency, digging technology of spillways, and so on. Because of these backgrounds, analysis on space-time character and the cause of formation, study of the affect of uncertainty to trend prediction for a new large-scale management of the provision of policy guidance and technical support for scientific use of water resource of Dongting Lake is very necessary and urgent. In the paper, the meaning of uncertainty and the theory and technique of assessment, forecast and pollution control plan are researched. The main contributions of this dissertation are described as follows.1 Assessment of water resource based on uncertainty multi-attribute analysis theoryThe uncertainty multi-attribute analysis model is one distinguishing model considering many kinds of attributes and based on Gray Assessment theory. According to management situation of Dongting Lake, multi-attribute assement model of water quality was constructed to analyze the situation of water quality of Dongting Lake, and the analysis model of water resource safeguard ability was to study on water quantity of Dongting Lake. The results reveal the status of aquatic quality is still urgent, the using efficiency of water resource is low and circs of regional water shortage occur contingently.2 Time-series analysis on water resource of Dongting Lake Considering the UncertaintyTime-series model was selected to analyze water level and dynamic change rule of water resource capacity of Dongting Lake in this paper. The results disclose the change characteristic of interannual trend, annual periods and contribution ratio of affect of uncertain factors. And the effect of uncertainty on forcasting result was analyzed too.3 Analysis on cause of the current situation of Dongting LakeSpecial geographical location, variance of regional climate and human reconstruction of underlying surface results in the difference of temporo-spatial distribution of water resource and aquatic environment of Dongting Lake. The effect of Three-gorge project, the Dredging project and the Breaking dikes for flood running and People resettlement from outside embankment to twon project on water resource of Dongting Lake were emphasized in the paper.4 Analysis on forecasting of water resource of Dongting Lake based on Uncertainty theory and RBF neural network modelBased on phase-space reconstruction theory and maximum Lyapunov exponent, the chaotic behavior of monthly water level of Dongting Lake was recognized. Then chaos RBF nenral network model was selected to forecast water resource of Dongting Lake, and the affect of uncertain factors to the precision of prediction were quantitatively analyzed. The result indicated that reducing mornitoring error was one of requirement to improve the precision of prediction. 5 Multiobject optimization of aquatic pollution control of in reach of Xiaojiang river of Changsha of Dongting Lake Improvement of environmental effectiveness, enhance the protection of surface water resource and control of water quality of water area were selected as aims to upbuild multiobject optimization model for aquatic pollution control. The model is beneficial to the harmonization of economy, environment and society, and offers scientific gists for achievement of comprehensive planning projects. The paper involved the Fuzzy Optimization theory, brought forward Fuzzy Genetic Algorithms which was selected to work out the result of multiobject planning model for aquatic pollution control.6 Selection of craftworks of sewage treatment of waterfront city of Dongting Lake considering effect of uncertaintyAs one of selection techniques, the uncertain multiobjective decision-making has simple accounting step. However how to scientifically standardize these uncertain numbers is still puzzling many users. All attitudes of these experts were suggest to be described as some intervals here, and the liminal numbers of these interval were used to account, then we gained the standardized numbers to construct the integrated decision matrix. Selecting craftworks of sewage treatment in small area of Changsha was used as one example in the paper. At the same time, we consider the sewage treatment in small area has its own characteristics, such as the multi-objective and the incompatible among these objectives, the stability and the uncertainty. After attitudes of experts were standardized, the integrated decision matrix was to compare these results, and we found the best one. The method leaves out bothering account steps and reduces the decision risk, so it is more applied.