Optimization Module Of Eco-environment Improvement Based On Water-saving In The Fringe Area Of Minqin Oasis

Minqin Oasis locates in the downstream of Shiyang River Basin. It is surrounded by the Badan Jaran Desert and Tengger Desert on its northern, eastern and western side. The potential evaporation is about 24 times as that of precipitation. Besides, its surrounding desert ranks the first of China's four largest source regions of sandstoms, which makes it the most demanding region in the process of eco-environment improvement in the arid areas of Northwest China.The eco-environemntal deterioration process in Minqin Oasis reflects the fact that over exploitation of human activities under the local dry and weak ecological system which brings about shortage of region water resources, soil drought as well as gradual declines of desert vegetation and artificial windbreak and sand-fixation forests, so it is significant to explore the optimization eco-environment improvement module.This paper does a detail study about the eco-environment improvement in the fringe area of Minqin Oasis and raises an optimization module based on water-saving - the Zhengxin Module. It does an evaluation of multi-objective decision with Zhengxin and other 6 representative cases in the fringe area of Minqin Oasis: Songhe, Wangmou, Huanghui, Weijie, Huazhai and Dongyun. By calculating the changes in the volumes and structure of local water consumption in the experimental and research zones, the paper analyzes the influence of the new module on local water resources. The paper also constructs an eco-environment appraisal index system of the research zone and sets up a rank about appraisal results with the Grey Relation Projection Method.The calculation result shows that, compared with other modules, the Zhengxin module has significantly improved the local eco-environment. Under the new module, the amount of total water consumption reduces by 3811.63×10~4m~3 with the rate of reduction at about 53.9%; the proportion of irrigation decreases from 97.6% to 89.3% while the ecological proportion rises from 0.6% to 4.2%; Meanwhile, the eco-environment quality raises to rankⅡafter the module's promotion, while the present quality is rankⅣand the ideal conditon is rankⅠ. The optimization module of eco-enviroment improvement based on water-saving thus brings about significant improvement on the local ecological conditions.