Study On The Multi-Objective Zoning Technology System Of Flood Discharge And Detention Function Of Wenanwa And Wetland Restoration

In view of the situation that the control function of reservoir engineering in Daqing River basin is further enhanced and the utilization probability of flood storage and detention area is further reduced,this paper aims to explore the ways and methods of ecological restoration in flood storage and detention area under the premise of fully guaranteeing the flood control safety of the upper and lower reaches.In the coordinated development of Beijing-Tianjin-Hebei and male vigorously construction under the background of the new district,highlighting the Daqing River basin ecological status,through the Daqing River ecological corridor is the important support of regional ecological construction tasks,as in the service of Daqing River downstream ecological corridor construction important node(wetland),Wenanwa wetland degradation problems to be solved of the flood storage and detention area,and Wenanwa located in lowlying areas,In the history,it was the place of flood inundation and natural flood storage,and the excellent hydraulic conditions were suitable for the restoration and maintenance of wetlands.This article,on the basis of the existing flood storage and detention Wenanwa,functional partition,by means of remote sensing and field exploration and the recognition of Wenanwa flood storage and detention area land use type and with the existing canal system arrangement,superposition of the DEM elevation data,combining ArcGIS water flooded analysis under different conditions of water and topography response relationship,the available land with water supply conditions,such as farmland,was taken as the priority area for wetland restoration.According to the water depth and inundation under different water inflow conditions,the principles and key points of vegetation restoration were determined based on the response relationship between plants and water.Wenanwa in fully ensure the flood storage and detention areas and on the basis of the upstream and downstream flood control safety of the river basin by means of partitioning technology and make full use of water resources and flood storage and detention area of wetland ecological restoration,the flood storage and detention areas and effectively using the multi-objective integrated with ecological restoration,so as to our country river basin flood storage and detention areas and find a feasible management and adjustment mode.The main work and understanding of this paper are as follows:(1)On the basis of this study Wenanwa terrain conditions and land use types and systems of the flood storage and detention area is decorated,in ensuring does not affect the premise of flood storage and detention areas and function,ecological function was proposed and expand the potential of wetland recognition and partitioning scheme,in Wenanwa flood storage and detention areas and identify potential wetland restoration area,and further divided into conventional area and expand the area of two parts,the conventional area consists of two parts:water area and buffer zone,while the expansion area consists of three parts: water area,land and water ecotone and buffer zone.(2)According to DEM of Wenanwa,ArcGIS software is used to identify the low-lying land;Then superposition irrigation and drainage canal system.According to the direction of canal system,further determine the depression that is convenient for water supply in the direct direction.At the same time,the land utilization is unused land or arable land,which meets the prerequisite land type requirements for restoration into wetland.(3)Taking the potential wetland restoration area as the center,overlaying the conventional water source conditions,including regional stormwater resources,reclaimed water and urban sewage discharge,verifying the recharging amount of the conventional water source in each depression,and calculating and allocating the regional rainfall amount according to the proportion of the production and congealing area of each depression in the total area of the whole region;Based on the principle of giving priority to replenish nearby depressions,the amount of reclaimed water and scattered domestic sewage discharged in cities and towns was allocated,so as to determine the water area of conventional areas and extended areas.(4)In view of the land and water ecotone in the development area,the water source conditions of rainwater discharge from the upstream Baiyangdian Lake are superimposed,and different water diversion conditions are set.The principle of passive flood evolution is adopted,and the hydrodynamic model and ArcGIS software are used to simulate the flooding situation of the depression under different water diversion conditions,and then the land and water ecotone is determined.(5)The width of buffer zone was determined by applying soil water characteristic curve and combining with the water physiological characteristics of restored wetland plants in conventional and extended zones.