The SLEUTH urban growth model was calibrated using two of the suitability maps: agriculture and environmental protection whereas the urbanization suitability layer was used for evaluating the results.
In the Discussion section below we note how our cropland suitability layer could be improved to capture the various forces of change that we have not included.
For example, one alternative cropland suitability layer in this analysis could relax the restriction on cropland development in protected areas according to data on the effectiveness of protected area management [87].
Our cropland suitability layer and the base yields (observed year 2000 yields) used in the crop production model are based on water availability trends of the late 20th century (and irrigation patterns when it comes to base yields).
Climate change and LULC change may result in shifts in water yield (precipitation less evapotranspiration), thereby making the cropland suitability layer and base yield estimates imperfect predictors of 2015 patterns in cropland productivity and base yields.
To begin to explore this issue we plot country-level changes in rainfed cropland grid cell area (cropland in cells assigned the potential rainfed yield on the cropland suitability layer) versus the projected change in average annual water yield on rainfed cropland grid cells (Figure 3).
