Identifying the spatiotemporal heterogeneity of the relationships between grain production and its determinants using the GTWR model across China.

Background: Ensuring adequate food production is essential to the stability and security of a country. This study aims to assess China's grain production (GP) from 2000 to 2020 and explore the dominant factors affecting the spatiotemporal dynamics of GP.

Results: The present study reveals a significant rise in China's GP capacity over the last two decades, although the growth rate has recently slowed. The GP in China is primarily concentrated north of the 'Qinling-Huaihe' line, with main grain-producing areas in Heilongjiang, Henan and Shandong Province. The gravity center of China's GP has shifted northeastward, and the regional disparities have increased, exhibiting a pronounced agglomeration effect, although the bipolar effect is gradually weakening. There is significant spatiotemporal heterogeneity in the influence intensity of each factor on GP, among which the grain yield per unit area was the most positive influential factor, followed by the proportion of fiscal expenditure support for agriculture, amount of agricultural chemical fertilizer and grain sown area. By contrast, the disaster-affected grain area and the number of grain growers have a weak negative impact on GP.

Conclusion: It is suggested that a combination of optimized agricultural fertilization practices and targeted policy support is the key to increasing grain yield per unit area and thus improving GP in China. © 2025 Society of Chemical Industry.