Spatiotemporal variations and driving factors of crop productivity in China from 2001 to 2020.

Abstract

Human activities have altered the quantity and distribution of cropland, and climate change profoundly affects crop productivity. However, the spatiotemporal patterns and driving mechanisms of crop productivity remain unclear. Here, we analyze the spatiotemporal evolution of Chinese crop productivity using long-term satellite observation data. We employ the residual trend analysis method to separate the relative contributions of climate change and non-climate factors to crop productivity. Our results indicate the following: (1) from 2001 to 2020, China's crop productivity increased by approximately 0.11 kgCm^-2yr^-1, which compensated for the decline in crop yields caused by a reduction in cropland area. (2) Crop productivity exhibits significant spatial heterogeneity, with notable differences between the southern and northern regions of China. Both cropland and crop productivity show a northward shift, with the migration distance of the mean center of crop productivity exceeding that of cropland. (3) Agricultural production inputs are closely related to crop productivity, but climate change remains the primary factor influencing changes in Chinese crop productivity. Crop productivity in northern China is more sensitive to climate change, and the dominant factors vary among different agricultural districts. (4) Over the study period, long-term crop cultivation in northern China has benefited the net primary productivity of surface vegetation, though the sustainability of production faces challenges. This study is of great importance for maintaining food security and promoting sustainable agricultural development, offering guidance for cross-regional cropland compensation.