Theory And Application Of Water Resources Optimal Allocation In Relation To Eco-environmental Water Demand In Haihe River Basin

Water resources is the material basis of the human beings'survival and sustainable development. With the rapid population increase, the social and economic development, and the people's living standard improvement, the requirement for the quanlity of water demand and the quatity of water demand is increases, but the available water resources is limited. Additionally problems of water pollution, waste of water resources and water shortage are increasingly serious. Contradiction between water supply and water requirement and deterioration of ecological environment have strained social development and improvement of people's living standard. Study of water resources optimization in relation to eco-environmental water demand is an effective way of solving the problem, which is important and meaningful to coordinative and sustainable development of society, economy and environment.Firstly the approach to water resources optimization is reviewed. The optimal allocation model of water quality and water quantity in relation to eco-environmental water demand is built up. The solving method of the allocation model based on improved Genetic Algorithms is put forward. Secondly the BP model, gray model and non-linear regression model etc. are studied, the combined forecasting model based on optimal combine principle is built, and the model is used in domestic, productive water demand forecasting and surface water supply forecasting. Lastly the reasonable allocation evaluation system is built. Take the Haihe River basin as an example, the results show that optimization model and the solving method is reasonable, both domestic and eco-environmental water demands can meet requirement, system coordination degrees all over 0.7, the combined model improves forecasting accuracy and reliability, the forecast precision is improved with a reduction of the mean relative error from 2.3% to 1.93%, the reasonable allocation evaluation system enriches the content of optimal allocation.The study provides a decision-making basis for water resources sustainable use and improvement of eco-environment in Haihe River basin.