Application of a Gridded Population Dataset to the Projection of Cropland Potential under Workforce Constraints

While ongoing climate change is projected to expand environmentally suitable cropland toward high-latitude regions, the practical utilization of this potential is increasingly shaped by socio-economic constraints. Previous studies have suggested that agricultural workforce availability, as a proxy for socio-economic transitions and interactions, acts as a bottleneck for cropland supply potential. In this study, we assess spatially explicit practical cropland supply potential by incorporating agricultural workforce constraints using gridded population datasets from WorldPop. A weighting map of agricultural workforce distribution was constructed based on national-level minimum distance thresholds between population pixels and cropland pixels, and was used to allocate agricultural labor spatially. Future cropland potential was then derived by applying land-to-labor ratios that represent technological advancement. Within this workflow, urbanization levels were reviewed by comparing WorldPop Global 1 and Global 2 datasets and population projection datasets, all classified based on DEGURBA definitions (EUROSTAT), with national urbanization statistics from the World Bank. In addition, agricultural workforce shares between rural and urban pixels were evaluated through comparison with ILO statistics. Our results indicate that agricultural workforce availability constrains the northward expansion of cultivable land. A southward retreat of workforce-available cropland potential is also projected in some regions, such as Central Asia, despite increasing environmental suitability. Beyond regional projections, this study further demonstrates an application channel through which high-resolution population datasets can be used to constrain and quantify human influences on the Earth system.

Acknowledgment: This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Ministry of Science and ICT (RS-2021-NR055516, RS-2025-02312954).