Agricultural policy and crop location: Long-run output and spatial climate risk consequences

Choices by farmers—notably what crop to grow, where—are not only influenced by spatially sensitive environmental attributes but also economic factors that respond to changes in government policies. In South Africa, the policy stance toward agriculture swung toward an extended period of support spanning the middle of the 20th century. Subsequently, the agricultural support policies were eliminated in the post-Apartheid period beginning in the 1990s. Using a purpose-built, spatially explicit data set for South African agriculture spanning the period 1918–2015, we show these structural shifts in agricultural policy regimes concord with major shifts in national corn price trends and variability, and the area planted to corn (accounting for half the country's cropped area). More subtly, and much less studied, we reveal that these switching policy regimes also aligned with changes in the location of crop production, with pronounced consequences for crop output and climate risk. At its peak, policy-aligned crop movement in South Africa reduced corn output by between 7.9% and 15.3%, and placed production in areas with reduced and riskier rainfall patterns. Upon removal of the policy distortions, the decline in total corn area continued, and the crop largely reverted to its predistorted, less climate-risky geographical locations. The geographical sensitivities of the agricultural policy–production–climate risk nexus we reveal suggest these locational aspects deserve more concerted analytical and policy design attention, especially in light of the longer run, spatially sensitive production and food security risk implications of the changing climate realities facing agriculture the world over.