Study On The Impact Of Water And Land Resources Exploitation On Water Resources Transforming In The Inland Arid Area

The inland arid area of China is very broad,such as Hexi corridor of Gansu Province, Ta Limu Basin and Zhun Ge'er Basin of Xinjiang Uygur Autonomous Region, Chai Damu Basin of Qinhai Province that are all the type of Gobi and generated by the dry climate condition. There are broad plain area and abundance heat resources of sun in these basins. The rivers in these basins are all derived from mountain area of basin. These surface water resources and groundwater resources which is transformed from them are very useful for the industry and agriculture development of the plain areas of these basins, so, the productivity of agriculture was enhanced and the plain area became the social economy development base of its basin. However, large-scale water and land resources exploitation intensified the impacts of human exploited factors on water resources transforming. The inter-transforming process of surface water resources and ground water resources was markedly changed. There out, sustainable development of social economy and security of ecological environment of inland arid area are threatened by this change. Shiyang River Basin is selected as the background study area because the water and land resources exploitation of this basin is the earliest basin of all basin in inland arid are, so the degree of water and land resources exploitation is the highest, the most severity ecological environment problem is too. The general water resources transforming system is come out by the analysis of water system characters, geologic structure and the mode of water and land resources exploitation. Six River Water System (SRWS) is selected as the main study area from three sub-water system of this basin to analysis the impacts of water and land resources exploitation on water resources transforming because this sub-water system is the most develop irrigated agriculture, the most variety types of irrigated area and the most representative system of all inland arid basins. Base on the analysis of impact of water and land resources exploitation on water resources transforming, the main water and land resources exploitation factors which reflect the degree of water and land resources exploitation are filtered, the main variables which reflect the state of water resources transforming are filtered too. The change process of the main water and land resources exploitation factors and the main variables which reflect the state of water resources transforming are analyzed by the practical data from the period 1991~2002. The degree of impact of water and land resources exploitation factors on water resources transforming is analyzed by absolutely gray relevancy degree, relatively gray relevancy degree and synthetically gray relevancy degree which are calculated by the theory of gray system. The model is upbuilded by the Artificial Neural Network (ANN). The input of the ANN model are the annual run off of SRWS, the water and land resources exploitation factors of the irrigated area irrigated by surface water and the irrigated area irrigated by ground water and spring. The outputs of this model are the main variables that reflect the state of water resources transforming. These variables are the annual change of groundwater table of he irrigated area irrigated by groundwater and spring. This ANN model can be used to simulate and forecast the impact of water and land resources exploitation on water resources transforming by the process of ANN training and verifying. In order to use the function of this ANN model more applicably and more conveniently, the visual manipulation platform of simulating and forecasting ANN model with powerful function and friendly interface is projected. The study on the impact of water and land resources exploitation on water resources transforming in Shiyang River Basin is representative in inland arid area. Then, the conclusion of this paper can be used as reference to boost the reasonable exploitation of water and land resources in other inland arid basin.