Study On Theory And Practice Of The River Ecosystem And Environment Demand Water

With the rapid development of our country's socio-economic, the problem of the river ecology and environment is increasingly serious, has become the bottleneck of sustainable development. Accordingly, the study is doing a research, about the theory and pratice of river ecology and environmental water requirement, and make the Ningmeng River,Longyangxia,Sanmenxia and Xiaolangdi, which on the main Yellow river and have a prominent problem about the river ecology and environment, as models. The main research results are as follows:(1) Proposed to use the measure of selecting typical years and determining the percentage by stages, to better the Tennant method to suitable the discharge seasonal rivers. Application examples show that the improved Tennant method was able to adapt to seasonal rivers.(2) Through the introduction of the ratio of the admitting water contamination concentration to the concentration guide of the third-level water, and the ratio of the contaminated sewage discharge concentration to the concentration guide of the third level water, makes a deduction of the dilution-ratio, combined with one-dimensional water quality model, advancing the resources dilution-ratio environmental water requirement method. Application examples show that this way to determine environmental water requirements of river than the one-dimensional water quality model is more simple and feasible.(3) The introduction of better difference,worse difference,better opposition and worse opposition, the degree of difference and antagonism has been refined, and improved the set pair analysis. Application examples show that the improved the set pair analysis of the multi-level comprehensive evaluation model to evaluate the results more reasonable.(4) Make the water balance theory and the water environmental capacity is not overloaded theoretical as foundations for the study, proposed the calculation method of river wetland ecological and environmental water requirement, get the minimum ecological and environmental water demand is 0.697 Bim3, the maximum ecological and environmental water demand is 6.553 Bm3 in the growing season of Henan Yellow River Wetland Nature Reserve.(5) Through the introduction of the proportion of using water and the resources dilution-ratio in the inner river and outer river, improved the river ecological water demand and the water quality comprehensive evaluation model. The improved model better than the original model:first of all, introducing the proportion of water in the inner river and outer river, can quantitative evaluate the degree of the proportion of ecology water demand and the limit of dilution-ratio of permittied flow, which becoming better with the influent. Secondly, the resources dilution-ratio can more fully reflect the extent of river pollution, better evaluate the environmental water requirements.(6) To the Yellow River as an example, calculated the suitable flow of the ecological and environmental of the Yellow River Toudaogua,Longmen,Huanyuankou and Lijing hydrologic station are 340 m3/s,500 m3/s,500 m3/s and 300 m3/s respectively; And do a comprehensive evaluation of the ecological water requirement of Yellow river from 2002 to 2005, results showed that:at discharge of the first level standard sewage and non-water diversion cases, the proportion of the Yellow River ecological use of water is 33.5%～54.5%, it is good at the Tennant Level, but the water quality does not meet the requirements. The research results offer technological supports for Yellow River water resources rational allocation, and the whole river resources unified scheduling and management.