Spatiotemporal Patterns and Driving Factors of Non-Grain Cultivated Land in China’s Three Main Functional Grain Areas

Food security, fundamental to national security, is challenged by the non-grain conversion of cultivated land. Based on the social and economic statistical data in China, this paper explores the spatiotemporal patterns and driving factors of non-grain cultivated land nationwide and in China’s three main functional grain areas during 2000–2020 with the help of the GIS Spatial Analysis and Spatial Metrology Model. The results show, first, that non-grain conversion initially increased but later decreased, with the non-grain level increasing from 30.61% in 2000 to 34.78% in 2003 and then decreasing to 30.28% in 2020; vegetables, fruits, and medicinal herbs were the main non-grain crops in most areas. Second, the non-grain levels showed an obvious spatial agglomeration state; the regions with low non-grain levels were located in the main grain-producing areas, and although the non-grain conversion levels in the main grain-producing areas decreased, the non-grain levels in these areas were clearly lower in the north than in the south. Moreover, the non-grain conversion levels in the main grain-sales areas and the grain production and sales balance areas increased. Third, rural population size, per capita GDP, the proportion of primary industry, and the land transfer rate are important drivers of the non-grain conversion of cultivated land nationally, but there are also significant spatial differences in the influence of these driving factors in different functional grain areas. This paper provides a new research perspective for analyzing the influencing mechanisms of cultivated non-grain land from the three functional grain areas. At the same time, it reveals the roots of the government’s predicament in the governance of non-grain cultivated land. It provides a reference for the government to formulate new policies for managing non-grain cultivated land.