Health Assessment And Ecological Water Demand Analysis Of The Shaanxi Reach Of The Weihe River

The ecological protection and high-quality development of river basins in the new period are major tasks facing Shaanxi Province,which requires systematic analysis and targeted governance.According to the principle of "discover problems-analyze problems-solve problems",select the assessment section and evaluate the health of the Weihe Shaanxi section from the aspects of water ecological integrity and social service function integrity;select the control corresponding to the assessment section Section,calculate ecological water demand,analyze the critical section's ecological water satisfaction status and the competitive water situation among various water users;on this basis,based on the problem,study the water scheduling and safeguard measures that serve ecological water demand,introduce Based on the concept of interval coordination,to meet the water requirements of multiple stakeholders,establish an ecological scheduling mechanism that adapts to strong competition conditions.The main contents are as follows:(1)Established a health assessment index system for the Shaanxi reach of the Weihe River and evaluated the water ecology.On the basis of an in-depth investigation of the river channel and the engineering profile,basic water ecological situation,and social and economic development of the Shaanxi section of the Weihe River,the Shaanxi section of the Weihe River is divided into 10 based on the landform changes,land use conditions,administrative divisions,and water function divisions of Shaanxi Province.Evaluate the reach;establish an evaluation index system in accordance with the requirements of the "Technical Guidelines for River and Lake Health Assessment",in which the indexes are independent,representative and scientific;assign weights to different indexes and select corresponding evaluation methods;Comprehensive evaluation of the water ecology of the Shaanxi section of the Weihe River from the integrity of the five aspects of hydrology and water resources,physical structure,chemistry,biology and social service functions,analysis of the evaluation results,and summary of the water shortage and poor water quality in the Shaanxi section of the Weihe River problem.(2)An appropriate ecological water demand calculation method is selected,and the ecological water demand of the Shaanxi reach of the Weihe River is calculated by item and its satisfaction is analyzed.Combined with the water function zoning of the Shaanxi Reach,select the control section that is suitable for the evaluation section,and calculate the sub-item ecological water requirements for each section;including ecological base flow,non-flood channel leakage and evaporation,and ecological flow in the spawning period of key sections 6 items including process,water demand for sediment transport in rivers,ecological water demand for wetlands and landscapes,and environmental flow,obtained the ecological water demand under different temporal and spatial distributions and different guarantee rates,and analyzed the satisfaction of ecological water demand with long series as the research object Degree;Finally,the ecological water demand of the key section is compared with the water consumption of other water users,and it is found that the competitive water situation will show a normalized trend,highlighting the urgency of the problem that needs to be solved urgently(3)Established an ecological water demand scheduling model,proposed a process for preparing long-,medium-and short-term water scheduling schemes,and constructed a multi-stakeholder coordination mechanism that adapts to strong competition conditions.Aiming at the problem that the ecological water demand is difficult to guarantee,the WROM model is used to analyze and calculate the ecological water flow scheduling,and the process of preparing the annual,monthly,and ten-year water flow scheduling plan is given.Based on this,the water flow scheduling plan during the dry season scheduling period is compiled and used as For example,the effectiveness of the model was evaluated;considering the water needs of multi-stakeholders,the concept of interval coordination was adopted,and a highly adaptive ecological scheduling mechanism was proposed;on this basis,from the construction of storage projects,water quality assurance measures,scheduling management,Informatization construction and water-saving society construction,etc.,elaborated measures to ensure ecological water demand,with comprehensive contents and effective methods.