Remaining Loyal to Our Soil: A Prospective Integrated Assessment of Soil Erosion on Global Food Security

Abstract

Soil loss by water erosion represents a key threat to land degradation worldwide. This study employs an integrated quantitative modelling approach to estimate the long-term global sustainability impacts of soil erosion. The global biophysical model estimates a mean increase of soil erosion rates of between 30-66% over the period 2015-2070 under alternative climate-economic scenarios, assuming different greenhouse gas concentration trajectories. In a subsequent step, projected soil erosion rates are converted into land productivity losses and inputted into an economic global simulation model to identify those regional hotspots where the greatest market tensions are expected to occur.The headline result is that soil erosion presents a major challenge to food security in vulnerable regions (Africa and some tropical regions). Indeed, for certain crops (particularly oilseeds) the threat of shortages is potentially significant. Secondly, exploring different long-term socioeconomic-environmental pathways quantitatively confirms the merits of sustainable management practises in coping with anticipated market and environmental stresses arising from soil erosion. Finally, free (and fair) trade is essential to allow less affected regions to expand (marginally) their production, thereby cushioning the market tensions that are expected to occur in more acutely affected areas of the world.

Keywords: Soil erosion, prospective interdisciplinary/integrated modelling, land productivity loss, computable general equilibrium, land footprints, climate-economic scenarios