Research On Urban Land Expansion And Green Space Conflict Evolution In The Eco-economic Zone Around Poyang Lake

The Ecological Economic Zone around Poyang Lake is a special economic zone with an important strategic conception of protecting the ecology and developing the economy.In order to build it into a world-class demonstration zone for the coordinated development of ecological economy,it is necessary to grasp the law of conflict evolution between urban land expansion and green landscape.This paper adopts the methods of landscape expansion index(LEI),land use dynamics,pixel binary model,morphological spatial pattern analysis(MSPA)and regression analysis to analyze the temporal and spatial characteristics of urban land expansion,types of urban expansion,and green space in the study area.The spatial and temporal dynamic characteristics of morphology and the temporal and spatial characteristics of vegetation coverage,and the selection of night light data to fully explore the coupling relationship between urban land expansion and human activities.On this basis,the Bayesian model of urban expansion and ecological protection space in the study area was constructed separately,and the spatial compatibility area and spatial conflict area of the two were identified through parameter learning and sensitivity analysis,and the compatibility area from 1995 to 2020 was analyzed.And the land use change in the conflict zone and the priority of different urban ecological protection and urban development.From the perspective of UDI area,the characteristics and changes of different land use in different periods are discussed,in order to plan the ecological environment of Poyang Lake in the central region.The delineation of the "three zones and three lines" of the economic zone provides a certain reference.Research indicates:(1)From 1995 to 2020,the expansion of construction land in the Poyang Lake Ecological Economic Zone increased,and the expansion rate showed a "medium-fast-medium-rapid" trend,and construction land changed from "incremental expansion" to "stock optimization".The main types of urban expansion are marginal,accounting for 66.88% of the total expansion;infill and enclave expansion are supplemented,accounting for 17.00% and 16.12% of the total expansion,respectively.In the process of urbanization,it is necessary to try to curb the expansion of the "big pie" to prevent the occurrence of ecological environment damage.In the research on the coupling relationship between urban expansion and human activities,stable light data at night can better reflect the interrelation and function between the two,and it can also monitor the dynamic changes of urban development to avoid the relationship between urban land expansion and the scope of human activities.Mismatch,improve the level of land resource utilization.(2)The large-scale habitat patches in the Poyang Lake Eco-economic Zone lack connectivity and there are many transition zones.As an important place for biological migration,there are few bridging areas and low landscape connectivity.The spatial distribution of green patches transformed into non-ecological land in the study area showed different characteristics in different periods,showing the characteristics of "fill-in" and "marginal" expansion.From 2000 to 2020,the vegetation coverage in the study area is mainly high,followed by medium vegetation coverage,accounting for 59.41% and 18.77%of the total area respectively.The area of extremely high vegetation coverage is about 11.28%of the total area.In the past 20 years,the area where the vegetation coverage is significantly degraded accounts for 14.67% of the total area,and the area where the vegetation coverage is improved accounts for 12.34%.(3)The areas of compatibility and conflict zones for urban expansion and ecological protection identified based on the spatial Bayes model are 15281.67 km2 and 7 356.64 km2 respectively.The amount of change in construction land and green space in different cities in the compatible zone and conflict zone has certain regularities and differences.The difference between the amount of change in construction land and green space in the conflict zone can reflect the priority of land use in the region,and is of great significance to the construction of a green ecological and economic coordinated development of the ecological economic zone around Poyang Lake.In addition,the UDI area divided according to the intensity of urban development is a new perspective to explore the conflict between urban expansion and green landscape.Through the change characteristics of different land use in the UDI area,analyze how to determine the priority of urban land and green space when land use conflicts occur,which is conducive to promoting the construction of ecological cities.