Recent Studies Of Water Consumption Of Hotan River Basin

Evapotranspiration is the final consumption and configurations of water resources in Northwest Arid Area of China. Whether the water cycle and translational research, or the allocation and utilization of water resources, the original supply and demand balance of water can not meet the requirements for in-depth understanding of the water movement law in arid zone, so the study of water consumption is very important and valuable. The analysis of water consumption should be one of the main content of water resources planning and design in arid area.Hotan River basin is located in the hinterland of closed mainland in China, with extreme drought condition around the year, and formed the country's largest temperate or warm temperate arid zone which has the typical characteristics of continental. The natural climatic conditions and the geographic location determine that Hotan has the hydrological characteristics which include scarce precipitation and severe evaporation, therefor, evapotranspiration is a important form of water movement in there. Through on-site visits, data collection and consultation from the local expert,we had a preliminary understanding of climate, development and utilizationn of water resources of Hotan River basin. Base on that, we studied the status of water consumption of Hotan River basin depthly with Hotan Oasis Dissipative Hydrological Model and obtained the following main results:(1) Hotan River runoff has a flat multi-year change duing to a stable source of water supply. But its annual distribution is so uneven that the water mostly concentrated in the summer. The runoff trends of the upper two branches are all not significant: Karakax River shows increasing trend, decreasing trend in the Yulong Kashgar River. And the two rivers all have insignificant cycle.(2) The paper described the basic principles and the structure of Hotan Oasis Dissipative Hydrological Model, adjusted some parameters of the model and re-verified them according to the current situation of water features of Hotan River basin in order to be applicable to the water simulation of the basin.(3) The paper studied and calculated the water balance and consumption of the basin using of Hotan Oasis Dissipative Hydrological Model to reveal initially the water movement disciplines. The results showed that the agricultural area of Hotan oasis was the main water body, the proportion of evapotranspiration of irrigation vegetation was large while the natural vegetation and bare lands'were small. The management of canal system was not in place so that the water had serious losses and more than half the amount of water losted on the way. Meanwhile, the river evaporation, seepage and flood overflow had suffered serious losses, accounting for about one third of total runoff river.(4) Based on above analysis of the amount of water, the paper explored that the cases which were Hotan River had low quantity of water than usual, Wuluwati reservoir reduced more flood, the phenomenon of privated and excessive diversion from the middle reaches of river was serious, and the water loss caused by the bifurcated flow on the both sides of the tributaries and the main stream all leded to the quantity of water from Hotan River to Tarim had reduced substantially in 2004,2007and 2008.(5) The paper analysed the current problems of development and utilization of water resources in Hotan River basin, and proposed some pertinece and reasonable suggestions.