Examining Urban-rural Construction Expansion And Driving Forces In Fujian Province During 1990 And 2020

Urban-rural construction land is one of the land use/cover types,and its expansion is an important part of land use/cover change(LUCC)research.With the accelerated development of urbanization in China,the spatial structure of land use/cover has undergone tremendous changes in Fujian Province,especially the sharp increase in urban-rural construction land.Quantitative analysis of the dynamic changes of land use/cover,urbanrural construction expansion and its driving forces in coastal provinces at different scales can provide a scientific basis for the rational allocation of provincial land use resources and territorial space planning.Based on the land use/cover datasets in 1990,2000,2010,and 2020,this paper takes Fujian Province,which is located on the southeast coast of China,as the research area.Firstly,it was analyzed by using the buffer gradient band method,dynamic index,transition matrix,spatial autocorrelation and hot spot analysis for the spatial-temporal evolution characteristics and spatial differentiation of LUCC under the sea-land gradient in Fujian Province during 1990-2020.Secondly,it was analyzed by using the methods of expansion area,average annual expansion rate,annual average growth rate and annual average expansion intensity index for the spatiotemporal variation characteristics of urban-rural construction expansion in Fujian Province.Finally,a combination of qualitative and quantitative analysis methods was used to explore the influence of factors such as nature,social economy,location and transportation,and policies on urban-rural construction expansion in Fujian Province at different scales,and obtained the dominant driving factors for the expansion of urban and rural construction land at different scales.The results show:(1)The main land use/cover types had a significant gradient change law,and there are obvious time series characteristics in the past 30 years.In terms of conversion types,the types of land use/cover change were mainly cultivated land,forest land,grassland,and urban-rural construction land,and the proportion of transfer change increases with the distance from the coastline.In terms of spatial distribution,there were significant northsouth differences in land use/cover type changes within different gradients.In terms of dynamics,comprehensive land use dynamics between different gradient zones showed a“decrease-increase-decrease” variation rule during 1990 and 2020.(2)The LUCC had significant spatial aggregation under the sea-land gradient in Fujian Province during 1990 and 2020.The results of cold and hot spots show that,it can be seen that spatially,the LUCC along sea-land direction of Fujian Province in each period had significant spatial differentiation characteristics and regional differences between north and south.In terms of time,the changes of hotspot areas in different periods showed spatial aggregation characteristics of “shifting from inland areas to coastal areas,and from south to north”.(3)Expansion degree of urban-rural construction land at different scales was different during 1990 and 2020.At the provincial scale,the index of urban-rural construction land expansion in different periods showed a trend of sharp rise and then slow decline.At the city scale,there are obvious regional differences between changes of urban-rural construction land expansion.At the sea-land gradient scale,expansion degree of urbanrural construction land in the coastal gradient zone was significantly higher than that in other gradient zones.In terms of spatial expansion,urban-rural construction land expansion in the municipal districts of Fujian Province could be divided into five types of expansion:single-core closed annular expansion,semi-closed annular expansion,linear expansion,core area expansion to the coast,and radial expansion type.(4)The dominant driving forces for urban-rural construction land expansion at different scales were similar and different durng 1990 and 2020,.At the provincial scale,GDP,the total population at the end of the year,and the distance to the city center are the dominant driving forces for urban-rural construction land expansion.At the sea-land gradient scale,the total population at the end of the year,GDP,and elevation are the dominant driving forces for urban-rural construction land expansion in the coastal gradient zone.Local fiscal revenue and expenditure,total retail sales of consumer goods,and the distance to major railways are the dominant driving forces for urban-rural construction land expansion in the transitional land zone.s The total population at the end of the year,the total retail sales of consumer goods,and the distance to the district center are dominant driving forces for urban-rural construction land expansion in the inland gradient zone.(5)Policy factors play a role in promoting urban-rural construction land expansion in Fujian Province,and it is also one of the reasons for the difference urban-rural construction land expansion under sea-land gradients in Fujian Province.National macro policies or regional development strategies have promoted the development of major counties and urban areas in the coastal gradient zone.Administrative division adjustment plays an important role in promoting urban-rural construction land expansion in some counties and urban areas in the transitional gradient zone.