Research On Soil Conservation And Habitat Quality Changes In Poyang Lake Basin Based On In VEST Model

Soil conservation and habitat quality are two important regulatory service functions provided by the ecosystem.Among them,soil conservation is of great significance for maintaining the safety of the regional ecosystem and ensuring the healthy development of the regional economy and society.In recent years,with the rapid social and economic development,the ecological environment in the Poyang Lake basin has gradually declined,which will seriously threaten the ecological security of the middle and lower reaches of the Yangtze River.This article will take the Poyang Lake basin as an example,combining land use data,rainfall data,soil data,slope data,and altitude gradients and other data,based on the InVEST model soil conservation module(SDR)and habitat quality module(Habitat Quality)to analyze the Poyang Lake basin Quantitative assessment of soil conservation function and habitat quality.The effects of different influencing factors on the characteristics of soil erosion,soil conservation and habitat quality changes in the watershed are discussed.The main conclusions of this paper are as follows:(1)Different altitudes,different slopes,and different types of land use have a greater impact on soil erosion in the Poyang Lake Basin from 1980 to 2018.The soil erosion modulus of the watershed in each year increased first and then decreased as the altitude increased,and the total amount of soil erosion showed a downward trend;the soil erosion modulus of the watershed in each year increased with the elevation of the altitude;The soil erosion modulus corresponding to different land use types in the year is from small to large: water area<unused land<construction land<cultivated land<forest land<grassland.(2)Different altitudes,different slopes,and different land use types have a greater impact on soil conservation in the Poyang Lake Basin from 1980 to 2018.The soil retention modulus in each year increased first and then decreased with the increase in altitude.The soil retention modulus in the area between 1200-1500 m above sea level was the largest;the soil retention modulus in each year showed an increase in slope Significant upward trend;the soil conservation modulus corresponding to different land use types in each year in descending order is: forest land> arable land> grassland>construction land> water area> unused land.(3)The habitat degradation in the Poyang Lake basin from 1980 to 2018 was greatly affected by other factors such as altitude gradient,slope,land use type and so on.The order of habitat degradation in different land use types in each year is:construction land> arable land> unused land> grassland> water area> forest land;the average habitat degradation in each year shows a decreasing trend with the increase in altitude;The average habitat degradation in the Poyang Lake Basin showed a trend of first decline and then increase with the increase of the slope.The area where the slope was less than 4.5° had the largest habitat degradation;the average degradation of the habitat in each year showed a first decrease with the increase of soil erosion intensity After increasing changes,the degree of degradation of the micro-erosion habitat is the highest,and the degree of degradation of the intensive-erosion habitat is the lowest.(4)From 1980 to 2018,the habitat quality of the Poyang Lake basin was greatly affected by other factors such as altitude gradient,slope,land use type and so on.Among the different land use types in each year,the habitat quality index in descending order is forest land>water area>grassland>cultivated land>construction land>unused land;the average habitat quality index in each year increases first and then decreases with the increase in altitude The habitat quality in areas below 300 m above sea level is the smallest;the habitat quality in the Poyang Lake basin in each year shows an upward trend with the increase in slope,and the habitat quality index in regions with a slope greater than 18° is the largest;the average habitat quality in each year generally varies With the increase of soil retention intensity,there is a rising change,and the extremely high retention intensity habitat has the highest quality.