Assessment Of Ecological Vulnerability In The Lakeside Of Songhua Lake And A Study On Its Ecological Restoration

The lakeside is a transitional and buffer zone between land and water ecosystems,it is an important part of the lake ecosystem.The lakeside ecosystem is relatively fragile.When exposed to external disturbances,it exhibits instability characteristics and weak self-recovery capabilities.Corresponding measures should be taken to strengthen the ecological restoration of the lakeside and promote the sustained and healthy development of the lakeside.Songhua Lake is a drinking water source in Jilin Province.It provides water for more than half of the population in Jilin Province.The overall water quality is relatively good.In recent years,unreasonable agricultural cultivation has occurred,resulting in the lakeside not only to accommodate the discharge of terrestrial and exogenous pollutants,but also to be affected by the leaching of pollutants from flooded land during the impoundmen.The water ecological environment is threatened.In order to provide technical support for the rehabilitation and rehabilitation of the Songhua Lake lakeside,the paper investigates and analyzes the land use of the Songhua Lake lakeside and the water quality from the lakeside to the water zone.Based on the“pressure-state-response” model,the ecological vulnerability of the lake is assessed,and thus the lakeside function regionalization was implemented.The main contents and achievements of this thesis are as follows:Based on the collection of hydrology,water quality,landforms and other data of the Songhua Lake lakeside,this paper interpret the remote sensing images and analyze statistical spatial distribution.The results show that the land use of the Songhua Lake lakeside is mainly by arable land,accounting for 44.91%,followed by water and water conservancy facilities land and grassland,accounting for 19.96% and 19.21% respectively.The woodland,transportation land and residential land is relatively low,accounting for7.97%,4.64%,and 3.30% respectively;For the lakeside with different land use types,this paper selects sampling points during the wet period and the peaceful water period,and conducts experimental analysis on the nutrient substances in the near-shore water.The total nitrogen concentration in the water is 2.04 mg/L,the total phosphorus concentration is 0.23 mg/L,and the concentration of chlorophyll is 6.25?g/L.The contents of total nitrogen,total phosphorus,and chlorophyll in the scenic spots and arable land are obviously higher than those in the other regions;This paper selects six indicators of artificial disturbance,lakeshore stability,lakeside vegetation cover,total nitrogen concentration,total phosphorus concentration,and chlorophyll concentration in the lakeside zone.Based on the pressure state response model,the ecological vulnerability assessment index system of Songhua Lake lakeside is established,and the AHP method was used to calculate the weight.The ecological vulnerability index of the Songhua Lake lakeside is distributed within the range of 1.412 to7.953.The average index is 3.78.It is mild fragile and the ecological system is relatively stable,but there is a potential ecological anomaly;Combining the ecological vulnerability assessment results and administrative divisions,this paper carries out functional zoning of the Songhua Lake lakeside.The northwest region named non-point source pollution control zone,and the main restoration measures are the construction of vegetation buffer belt and the repair of the hydro-fluctuation belt.The southwestern region named ecological experience tourism zone,and the main restoration measures are the repair of the hydro-fluctuation belt and ecological landscape construction and cultural protection.The southeastern region named wetland ecological protection zone,and the main restoration measures are the repair of the hydro-fluctuation belt and the construction of natural wetland.The northeastern region named Jiaohe ecological reserve zone,and the main restoration measures include the construction of vegetation buffer belts,repair of the hydro-fluctuation belt,construction of natural wetland,and development of green industry.