Coupling Coordination and Spatial-Temporal Evolution of Water-Land-Food Nexus: A Case Study of Hebei Province at a County-Level.

Exploring the interaction between water, land, and food (WLF) is a premise guaranteeing to ease resource restrictions and achieve sustainable development in major agricultural production areas. We chose 26 indicators to build a WLF nexus evaluation index system. We used the coupling coordination model to measure the coupling coordination degree of the WLF nexus in 15 prefecture-level cities and 151 counties under the jurisdiction of Hebei Province in 2000, 2005, 2010, 2015, and 2020. Then, the spatial correlation was analyzed using the global and local Moran's I. Finally, the regional differences and spatiotemporal patterns were analyzed using a spatial gravity center model and kernel density estimation. The results are as follows: (1) In 11 cities, the comprehensive evaluation index of the WLF and of each subsystem shows a fluctuating upward trend. More than 95% of the counties' comprehensive evaluation indices improved, and the difference between counties in the north and south narrowed after 2010. (2) The spatial pattern of the WLF in counties has evolved from a pattern of "high in the south and low in the north" to "high in the north and low in the south", with the development speed of the north being higher than that of the south. (3) The coupling coordination degree of the WLF has a positive spatial autocorrelation relationship in different counties; however, the spatial connection eventually deteriorates, and the geographic pattern exhibits "agglomeration decrease" characteristics. In Hebei Province, the WLF coupling coordination rate slowly improves, and there is a significant development gap between counties. Therefore, local conditions should be taken into consideration when implementing measures to reduce the conflict between water, land, and food in actual regional conditions. [ABSTRACT FROM AUTHOR]