Examining Differentiation Regularity of Sea-Land Gradient in Spatiotemporal Evolution of Land Use in Fujian Province over the Past Three Decades

Abstract

Based on the land use data of Fujian Province in 1990, 2000, 2010, and 2020, we analyzed the spatiotemporal change characteristics of land use types, the spatial differentiation of cold and hot spots under the sea-land gradient using the buffer gradient zone method, and the reasons for spatial differentiation of land use change. The results showed that: 1) the area changes of main land use types had different trends with increased distance from the coastline in the past 30 years. Among them, the change of cultivated land and urban and rural construction land area showed a gradient trend of continuous decrease, and the changes in the area between them within 20 km from the coastline were the largest, which were -1,317.12 and 1,799.8 km2, respectively. The change of forestland and grassland area showed a trend of "decreasing, increasing and decreasing" and concentrated in the 140-240 km gradient zone; 2) from the perspective of conversion types, the proportion of the first 10 land use types changed mainly from cultivated land and grassland to forest and from cultivated, forest, and grassland to urban and rural construction land in the following order: coastal gradient zone (44.23%), transitional gradient zone (37.31%), and inland gradient zone (15.03%). Regarding spatial distribution, the decrease in cultivated land and the increase in urban and rural construction land were mainly distributed in the coastal gradient zone, while the grassland decrease and woodland increase were mainly distributed in the transition and inland gradient zones; 3) from the perspective of the comprehensive dynamic degree, the comprehensive dynamic degree within 20 km from the coastline was the highest (0.75%) in the past 30 years, and the degree of change was the most severe. Concerning a single dynamic degree, the dynamic degree of urban and rural construction land showed a gradient change that first increased and then decreased, and its rate of change was much higher than that of other types; 4) land use change has significant spatial heterogeneity under the land-sea gradient, and taking the year 2000 as the time boundary, the hot spots showed the spatial aggregation characteristics of "transferring from inland areas to coastal areas" and from "more in the north and less in the south" to "more in the south and less in the north". The characteristics of land-sea gradient differentiation of land use change are closely related to regional development strategies and ecological environment construction policies at different stages of Fujian Province from 1990 to 2020.

Keywords

• land use change
• sea-land gradient
• buffer gradient band method
• regional development strategy
• urbanization
• fujian