Global high-resolution estimation of cropland suitability and its comparative analysis to actual cropland distribution

Abstract

: Global 500-m (18-arcsec) resolution cropland suitability was estimated using recently developed high-resolution global cropland data and a digital elevation model. The high-resolution estimation more precisely represented topo‐ graphical constraints to agriculture that were not adequately reflected in previous low-resolution estimates. It also suc‐ cessfully suppressed the overestimation of cropland suit‐ ability on areas with steep slopes. Furthermore, the distinc‐ tion of rainfed and irrigated cropland removed suitability overestimation induced by human agricultural intervention and enabled more natural and realistic estimation of crop‐ land suitability. The comparative analysis between the esti‐ mated land suitability and actual cropland distribution revealed that, if only natural condition is considered, it is possible to expand cropland area by 9.25 million km 2 , which is more than needed in the future while socio-economic factors controlling cropland suitability should be considered for more practical assessment. The newly developed highest-resolution cropland suitability map is expected to contribute to solving upcoming water, energy, and food issues, by integrating with water resource models and biomass studies.