Spatiotemporal Reconstruction of Cropland Cover on the Korean Peninsula over the Past Millennium from Historical Archives and Remote-Sensing-Based Data

Historical cropland reconstruction is crucial for modeling long-term agricultural dynamics and assessing their climatic and ecosystem impacts, while also providing critical regional benchmarks for improving global land-use datasets. This study presents a millennium-long reconstruction of cropland area at the provincial level for the Korean Peninsula by integrating multi-source historical cropland records, land surveys, and modern statistical and remote-sensing-based data. Then, a land suitability model for cultivation and a spatial allocation model were developed by incorporating topographic, climatic, and soil variables to generate 10 km resolution gridded cropland data over the past millennium. Our analysis revealed a long-term increasing trend in cropland area at the provincial level over the past millennium, with significant spatial and temporal variations. Spatially, cropland was primarily distributed in western coastal areas, with historical southward expansion. After the peninsula’s division, trends diverged, with continued growth in the north Korea but a decrease in the south Korea by 2000. The spatial allocation model validation results show strong spatial and quantitative agreement between the reconstructed historical cropland and the remote-sensing-based data, with 72.12% of grids differing by less than ±20%. This high consistency confirms the feasibility of the applied reconstruction method.