Identification of Spatiotemporal Dynamics of Non-Grain Cropland and Its Geographical Differentiation Characteristics in the Guanzhong Region, China

Ensuring food security is a top priority for China, and non-grain production (NGP) of cropland can substantially reduce food production. As the core grain production base in Shaanxi Province and even Northwest China, the Guanzhong region’s evolution of NGP is very important. Based on the single-phase remote sensing data and the time-series curve, this study identifies explicit non-grain production (E-NGP) and implicit non-grain production (I-NGP) of cropland in the Guanzhong region from 2001 to 2020. Spatial analysis and gradient analysis are applied to characterize the spatiotemporal dynamics, differences in reversibility, grain loss, and driving factors of E-NGP and I-NGP. The results show that the area of cropland used for NGP in the Guanzhong region has gradually increased over the past two decades. In 2020, the area of E-NGP reached 4212.06 km2, while that of I-NGP accounted for 8300.16 km2. The total cumulative loss attributed to NGP in 2020 reached 11.58 million tons, and the grain loss caused by I-NGP was approximately twice that of E-NGP. Moreover, cropland used for I-NGP exhibits greater instability and reversibility, making it more susceptible to human intervention than that under E-NGP. The cropland used for E-NGP is mainly distributed around urban areas, where it is often converted into construction land. The cropland used for I-NGP gradually expands from north to south, with areas south of the Weihe River increasingly converted into economic fruit forests. E-NGP is driven by both terrain and socioeconomic factors, while I-NGP shows a stronger natural geographical dependence. This study defines the scale boundaries and driving factors of NGP in the Guanzhong region, reveals its substantial threat to grain production capacity, and provides theoretical support for regional policy implementation and the formulation of refined cropland protection policies in the Guanzhong region.