Research On The Relationship Between Beijing-Tianjin-Hebei Ecological Space Network And Regional

Under the background of global warming,with the continuous advancement of urbanization process,the proportion of urban land was increasing,the proportion of ecological land was decreasing,and the landscape tend to be fragmented,resulting in a large number of ecological environmental problems,among which the urban thermal environment problem is very serious.However,the ecological space of urban agglomerations could effectively alleviate the thermal environment problems of urban agglomerations,and the reasonable planning of ecological space pattern and network structure could effectively reduce the temperature,which was of great significance to alleviate the thermal environment problems.This paper focused on the impact of vegetation and water evolution,landscape ecological risk on land surface temperature in Beijing-Tianjin-Hebei Urban Agglomeration,and discussed the influence mechanism of ecological spatial pattern and ecological spatial network structure on land surface temperature.The research methods and results were as follows:(1)The spatial and temporal variation characteristics of vegetation,bare land and water were analyzed by using a linear regression model.This paper studied the degree of urban expansion of Beijing Tianjin Hebei Urban Agglomeration by using urban expansion index.According to the actual situation of Beijing-Tianjin-Hebei,the landscape ecological risk index was constructed.Spatial autoregression and geographically weighted regression were used to analyze the spatial aggregation pattern and local correlation of landscape ecological risk.In the past 15 years,the expansion of architectural space in Beijing-Tianjin-Hebei Urban agglomeration had directly or indirectly changed the original landscape pattern.Low ecological risk areas were mainly distributed in the city and its surrounding areas.The accelerated expansion of urban space will cause the decline of landscape ecological risk.The landscape ecological risk in 2003,2008,2013 and 2018 was positively correlated with land surface temperature.(2)Based on landscape ecology and spatial econometrics,the pattern characteristics of ecological space and land surface temperature in Beijing-Tianjin-Hebei Urban Agglomeration were analyzed.Landscape type percentage index(PLAND)had a great impact on land surface temperature,and the land surface temperature in the area with high ecological space patch abundance was lower.The larger the patch area was,the more obvious the cooling effect was.The more complex the patch shape was and the longer the patch boundary was,the better the cooling effect was.The higher the aggregation index(AI)of ecological space patches was,the lower the surface temperature was.(3)The potential ecological corridors were extracted based on the cost-path model.The relationship between the topological structure of the ecological space network and the land surface temperature was explored.The ecological corridor could reduce the temperature of the surrounding land surface.In a certain area,the denser the corridor was,the lower the surface temperature was,and the higher the degree value of ecological space patches was,the lower the surface temperature was.The higher the value of cluster coefficient,the higher the surface temperature.