Optimal Allocation Of Water Resources Based On Vegetation Ecological Water Demand In The Desert Marginal Zone

The rapidly developmental industrialization process is destroying fragile ecological environment in the desert marginal zone while ecological restoration is becoming more and more important.Because vegetation is the most important key element in vegetation restoration process and water source is the crux of vegetation restoration in arid areas,optimal allocation of water resources that based on vegetation ecological water is imperative.However,because of the differences about vegetation restoration condition of every unit area,the vegetation ecological water shortage is different,which has a big impact on the optimal allocation of water resources based on vegetation ecological water demand.Meanwhile,the harmony is also the primary content of optimal allocation of water resources between vegetation ecological system and economic development.This paper has four parts:Part one:Due to the size of the vegetation coverage erosion and desertification area is in a state of mutual drive,this part of the content,in the form of an analogy epidemic model,establishes the vegetation restoration model by the geometric theory of differential equation to study the state of vegetation restoration and the stability by analyzing relationships among parameters under water conservation factor in model.At last,according to vegetation coverage area variation of the south rim of Gurbantunggu,the model's suitability is verified and the model also determines the impact of water conservation efforts on vegetation restoration.Part two:This part unitize the area to determine the optimal unit area,namely the size of the vegetation coverage area that can resist the erosion of desert,and determine the erosion unit area by the coverage calculation formula.Vegetation ecological water demand of every unit area is calculated by the method based on ground evaporation,and the vegetation ecological water shortage of other unit areas is calculated by contrasting.It provides some theoretical basis for water resources optimization.Part three:Considering the factors of economic development and the progress of science and technology,water users and water distribution are analyzed for providing the optimal allocation of water resources reasonable basic amount.Part four:Based on the desert marginal zone special geographical situation,the water resources allocation principles is determined and water resources optimal allocation model is established by joining living water,economic efficiency,the ecological environment efficiency and the harmony which own the evaluation function based on membership functions between economic efficiency and ecological efficiency;Finally through the simulation solution,the effectiveness of the model is determined.Based on the above contents,we can see that the vegetation restoration model can not only minimize the resources needed for vegetation restoration,but also controls the vegetation restoration status,and provides basis for the optimal allocation of water resources based on the ecological water demand of vegetation;In addition to satisfying the basic water demand of each water user,the optimal allocation model of water resources also greatly balances the coordination of ecological water use for vegetation and water for economic development and meets the basic requirements for sustainable development.