Spatiotemporal evolution and driving mechanism of rural multi-functions in the Yangtze River Delta

Rural is a spatial regional system concept, referring to the region outside the city. The rural regional system in China has changed gradually under the impact of rapid urbanization, particularly from the traditional single agricultural production to the industry, leisure service, and commodity retail multiple functions. Much more emphasis has also been posed on the multiple functions of agriculture and countryside. It is very necessary to scientifically evaluate the level of rural multi-function for the regional differentiation and type characteristics in the context of rural revitalization strategy. The formation and evolution of driving mechanism can also be of practical significance to promote the implementation of rural revitalization. Taking the Yangtze River Delta as a case study and the county as a research scale, an evaluation index system was constructed to quantitatively measure the rural multi-function level using the entropy weight TOPSIS. The connotation and characteristics of rural multi-function were also defined during this time. The spatial-temporal evolution and driving mechanism of rural multi-function during the study period were then analyzed to integrate the GIS spatial analysis, spatial autocorrelation, and geographic detector model. The results showed that: (1) The rural multi-functional level was ever improving since 2000. There were significant regional differences in the rural multi-functional level, indicating an overall feature of "high in the south and low in the north". The difference in functional level was ranked in the order of the rural production function > rural living function > rural ecological function. (2) There was a significant positive autocorrelation in the overall spatial distribution of rural multi-functional functions, indicating a high (low) - high (low) agglomeration pattern. Locally, the H-H type of rural production function was mainly concentrated in northern Anhui, whereas, the H-H type of rural living function was in southern Jiangsu, and the H-H type of rural ecological function was distributed in southwest Zhejiang. (3) The evolution of rural multi-function depended mainly on the natural and geographical environment, as well as the economic and social development factors. There was a gradually increased effect of economic and social factors on the evolution of rural multi-function. By contrast, the natural environmental factors gradually decreased the effect intensity. Among them, the regional economic strength, urbanization level, and fixed asset investment were the leading factors in the evolution of rural multi-function. The interaction driving force with some factors was stronger than that with the single factor. The interaction type was mainly enhanced by two factors. Therefore, the rural transformation can highlight the dominant functions of different regions in the future, according to the evolution characteristics and driving mechanism of rural multi-function since the 21st century. An optimization mode was also constructed for the dominant function of rural regions. A combination was made for the functional status of each regional type, resource, and environment characteristics, as well as the regional development background. A differentiated optimization strategy of rural regional functions can also be expected to serve as the rural revitalization, according to local conditions in the Yangtze River Delta.