| With the expansion of population and the growth of economy,the demand for resources increases dramatically,and human beings constantly allocate and utilize various resources.Frequent human activities will lead to changes in the area,shape and spatial distribution of various landscapes,which will affect the structure and function of the ecosystem,material circulation and energy flow,and ultimately affect the supply and maintenance of ecosystem services.It is of great significance to elucidate the influence mechanism of landscape pattern evolution on ecosystem services for regional landscape ecological construction,land use structure optimization and social and economic sustainable development.Based on land use data,meteorological data and soil data in 1990,2000,2010 and2020,the evolution characteristics of three typical ecosystem services（water conservation,soil conservation and carbon storage）in the Ganjiang River Basin were quantitatively evaluated by In VEST model.Based on Fragstats 4.2,landscape index method was introduced to analyze the change of landscape pattern in the study area.On this basis,bivariate Moran’s I method was used to test the spatial correlation between landscape index and typical ecosystem services,and the spatial regression model was further used to express the response degree of each typical ecosystem service to landscape index.The main conclusions are as follows:（1）From 1990 to 2020,the cultivated land in Ganjiang River Basin decreased and the construction land increased in a large area,the construction land increased by82.70%.The transfer between landscapes mainly occurred between cultivated land,forest land,grassland and construction land,and the change of cultivated land,forest land,grassland and water area were not obvious,PS all approached 0,two-way equilibrium conversion,the overall fluctuation was small,but showed a certain volatility in the process.The development of construction land is close to the sub-extreme unbalanced situation,which is mainly transferred and expanded obviously.The landscape pattern was fragmented on both the type scale and landscape scale,the patch shape tended to be complex,and the landscape diversity increased.（2）The water conservation and soil retention in the Ganjiang River Basin showed an upward trend,and the carbon storage showed a downward trend,with changes of10.56 mm,16.24 t hm–2 a–1 and 1.22 t hm–2 a–1,respectively.In terms of spatial changes,53.11%of the regional water conservation and 69.23%of the regional soil conservation in the study area showed an increasing trend,and 70.74%of the regional carbon storage showed a decreasing trend,among which,the areas with obvious increase in water conservation and soil conservation were mainly located at the junction of Longnan County,Ningdu County and Xingguo County,the junction of Lianhua County and Yongxin County,and the areas with obvious carbon storage reduction were mainly located in various urban districts,such as Nankang District,Zhanggong District,Jizhou District,Yuanzhou District,etc.（3）The Shannon Diversity Index（SHDI）and patch density（PD）are the main landscape indicators affecting water conservation,soil conservation and carbon storage in the Ganjiang River Basin,and they are negatively correlated with each ecosystem service.In addition,water conservation is also sensitive to the separation index（SPLIT）,which is negatively correlated in space.The responses of soil conservation and carbon storage to mean patch area（AREA＿MN）were strong,and there was a positive spatial correlation with AREA＿MN.（4）In the territorial spatial planning of the river basin,the bivariate LISA cluster map identified four clustering patterns among the landscape pattern and ecosystem services of the Gan River Basin,and corresponding measures can be taken according to local conditions in different regions.For example,strict ecological protection measures should be taken in the"low heterogeneity and fragmentation-high ecological service"area;the expansion of construction land should be avoided in the"high heterogeneity and fragmentation-high ecological service"area;more ecological space can be created in the"high heterogeneity and fragmentation-low ecological service"area;consideration should be given to more ecological restoration projects and to prevent the sprawl of construction land in the"low heterogeneity and fragmentation-low ecological service"area. |
PDF Full Text Request