The Relationship between the Spatial and Temporal Evolution of Land Use Function and the Level of Economic and Social Development in the Yangtze River Delta.

To explore the spatiotemporal evolution characteristics of land use function and its correlation with social and economic development levels, taking the Yangtze River Delta region as an example, we quantified the multifunctional land use in the Yangtze River Delta region from 2000 to 2020 on a 5 km × 5 km grid and analyzed its spatiotemporal evolution characteristics. Each city's comprehensive measure of economic development used the projection tracing method. Person's method of interpretation was used for correlation between the spatial and temporal evolution of land use functions and the level of economic development and its coupling association. The study shows that: (1) from 2000 to 2020, the agricultural production function > ecological function > living function > non-agricultural production function in the Yangtze River Delta, but the non-agricultural production and living functions were gradually increasing, while the agricultural production and ecological functions were decreasing. In terms of spatial distribution, the agricultural production function decreases significantly around the built-up area due to the expansion of the built-up area. The non-agricultural production function strengthened around the central city in a network pattern and had a path-locking effect. Topography limits life functions, with high north and low south partially overlapping with non-agricultural production functions. Furthermore, the ecological function was high in the south and low in the north and continues to weaken due to the interference of human activities. (2) The spatiotemporal heterogeneity of different functions generated trade-offs/synergies. The trade-off relationship was prominent in agricultural production and non-farm production function and living function, and non-farm production and living function and ecological function during the study period. Conversely, agricultural production and ecological functions and non-farm production and subsistence functions were generally synergistic. Spatially, there was substantial spatial heterogeneity in the trade-off/synergy relationship between the two functions. (3) There was a clear correlation and spatial coupling between land use function indices and economic development levels in the whole region and sample zones. Still, the dynamic and regional nature of the evolution of land use functions results in sudden changes and jumps in different functions in space. Therefore, in the future integration of the Yangtze River Delta, it is necessary to pay comprehensive attention to the morphology of different land use functions and their synergy/trade-off relationship and to adjust the spatial governance strategy promptly according to the local conditions and the situation.