Analysis And Simulation Of Water Utilization Structure In Shiyang River Basin Under Changing Environments

The signify problem to the development of arid zone is water, and the rational use of water is the key to solve ecological problems and the poverty problems in these areas. Analysis of water withdrawal and water utilization structural changes, finding the mechanism of it response to environmental change, building valuable water forecasting models is important to achieve sustainable use of water. Shiyang river basin is an important inland river basin in northwest China's arid region. It has significance to realization the sustainable use of water resources through study on the water withdrawal and water Utilization structural in this area.This paper based on Shiyang river basin water utilization structure changes in recent years, the driving force factors which led to these changes has been analysed. The driving force models of water utilization structure which built on the actual situation have been established for simulation and prediction the evolution of water utilization structure in Shiyang river basin.It shows that the total agricultural water consumption is the main component of the total consumption of water. Agricultural water consumption trends smoothly without significantly increase. Socio-economic and agricultural structure factors are the main driving force factors. GM (1,1) and artificial neural network BP model to achieve simulation and analysis of the trend of water utilization structural in Shiyang river basin.The forecasts for water utilization structure in GM (1,1) model showed that the reduction of agricultural water consumption, and the significantly increased of industrial and residential water consumption. The proportion of water utilization structure is 89.93:5.54:4.51 in 2003, turn to 84.38:6.68:8.95 in 2020. The forecasts for total water consumption increased 0.66 billion m~3 from 2006 to 2020. Based on the current developed level, situation the evolution of water utilization structure in the BP model, the results shows the smooth change in the total consumption of water, the dropped of agricultural water consumption, the slow growth of industrial water and significantly increased in residents living water. The total water consumption in 2020 forecast to 2.78 billion m~3, The proportion of water utilization structure is 88.79:6.29:4.92. The paper also study on the agricultural water use. The results showed that the scale of agriculture, agricultural area and climatic factors are the driving force of he changes in irrigation water demand.Based on the current developed level(scene I), and based on the basin management planning (scene II), the forecasts for agricultural irrigation water demand in the BP artificial neural network models showed: decreased by 1.13 billion m~3 form 2020 to 2003 in scene I. fell to 27.44 percent in scene II. From the comparison of models, artificial neural net work BP model is superior to the multiple linear regress model. Two models in different scenarios, the agricultural irrigation water demand showed the same downward trend. At the same time, the policy adjustment would reduce the agricultural irrigation water demand.At last, the further research on water utilization structure and the water use are put forward.