Impact of Climate Change on Crop-cropland Coupling Relationship: A Case Study of the Loess Plateau in China

Climate change brings new challenges to the sustainable development of agriculture in the new era. Accurately grasping the patterns of climate change impacts on agricultural systems is crucial for ensuring agricultural sustainability and food security. Taking the Loess Plateau (LP), China as an example, this study used a coupling coordination degree model and spatial autocorrelation analysis to portray the spatial and temporal features of crop-cropland coupling relationship from 2000 to 2020 and explored the impact law of climate change through geographically and temporally weighted regression (GTWR). The results were as follows: 1) the crop-cropland coupling coordination degree of the LP showed a gradual upward trend from 2000 to 2020, forming a spatial pattern with lower values in the central region and higher values in the surrounding areas. 2) There was a positive correlation in the spatial distribution of crop-cropland coupling coordination degree in the LP from 2000 to 2020, and the high value-low value (H-L) and low value-low value (L-L) agglomerations continued to expand eastward, while the spatial and temporal evolution of the high value-high value (H-H) and low value-high value (L-H) agglomerations was not obvious. 3) The impacts of climatic elements on crop-cropland coupling coordination degree in the LP showed strong heterogeneity in time scales. The inhibitory impacts of summer days (SU) and frost days (FD) accounted for a higher proportion, while the annual average temperature (TEM) had both promoting and inhibiting impacts. The impacts proportion and intensity of extreme heavy precipitation day (R25), continuous drought days (CDD), and annual precipitation (PRE) all experienced significant changes. 4) In space, the impacts of SU and FD on the crop-cropland coupling coordination degree varied with latitude and altitude. The adaptability of the LP to R25 gradually strengthened, and the extensions of CDD and increase of PRE led to the increasing inhibition beyond the eastern region of LP, and TEM showed a promoting impact in the Fenwei Plain. As an important grain-producing area in China, the LP should actively deal with the impacts of climate change on the crop-cropland coupling relationship, vigorously safeguard food security, and promote sustainable agricultural development.