Study On Simulation And Restoration Of Wetland Vegetation Community In Huangjinxia

The Han-to-Weihe River Diversion Project is a very complex water resources allocation system project.The project is extremely difficult,involves a wide range of areas,and has many influencing factors.Such a large-scale project will inevitably bring a series of impacts on the environment and biology.After the completion and operation of the Golden Gorge Reservoir,the water level,flow velocity,pollutant concentration and other factors in the river have changed to varying degrees due to changes in reservoir storage and operation scheduling methods.This will affect the growth of vegetation communities on both sides of the wetland in the reservoir area,and even lead to the death of some vegetation communities that are sensitive to flooding and water quality changes,resulting in soil erosion,water quality deterioration,and vegetation community ecosystem degradation.The ecological functions and landscape patterns of both sides of the strait pose a serious threat.Therefore,it is particularly important to analyze the relationship between water flow and vegetation.The ecological restoration of vegetation communities plays a vital role in maintaining local species,biodiversity,and ecological stability.Relying on the Shaanxi Provincial Water Conservancy Science and Technology Project Fund,this paper uses the methods of field investigation,MIKE simulation,hydraulic model test,Meta analysis,and theoretical analysis to study the vegetation community restoration of the Golden Gorge Wetland.The impact of hydrodynamic and water quality changes on the vegetation community after the construction of the reservoir has many functions such as soil consolidation and water purification,water purification,slowing down the flow rate,maintaining the balance of species diversity in the study area,and protecting the habitat of precious birds such as the crested ibis.The main research results of this study are as follows:(1)Use the MIKE model to analyze the changes in the water level,flow velocity,submerged range,and water quality indicators(nitrogen,phosphorus,chemical oxygen demand)in the Yangxian section of the upstream river before and after the construction of the Golden Gorge reservoir,and analyze the changes due to the water level and water quality.The negative impact of changes on vegetation.(2)Based on hydraulic experiments to simulate the slow flow effect of emergent plant communities under different flow rates and densities,it is found that when the emergence vegetation density is 108 plants/m2,the slow flow effect is better than 202 plants/m2,54 plants/m2;Based on Meta analysis to study the water purification and decontamination ability of six emergent plants,it is found that the emergent plants with better water purification ability are reeds,cattails,and canna.The two research results are applied to the ecological restoration design of the vegetation community in the Golden Gorge Wetland.(3)In view of the current problems in the wetland in the Golden Gorge reservoir area and the impact of changes in water flow after the construction of the reservoir,the arrangement of emergent plant communities+terrestrial plant communities was proposed;three types of revetment designs and spatial arrangements were proposed Methods:The study area was divided into four different types according to the degree of impact of water flow:Crested Ibis Habitat Wetland Vegetation Community Restoration Design,River Turbulent Bend Vegetation Community Restoration Design,Normal River Floodplain Vegetation Community Restoration Design,and Reservoir Bay Section Vegetation Community Restoration Design The regional vegetation community restoration design plan,and the vegetation community management plan is proposed according to different periods.To ensure that the impact of the construction of the reservoir on the wetland vegetation community is minimized,and at the same time,it can better play a number of functions such as water and soil conservation,water purification,protection of the crested ibis habitat,and maintenance of species diversity.