Spatially explicit life cycle impact assessment for soil erosion from global crop production.

We derived spatially explicit erosion rates in kg of soil lost per kg of crop as a function of crop choice and management practice on a global scale. These so-called characterization factors (CFs) can be used in product life cycle assessment studies to determine the impact of crop cultivation on soil erosion. We used the biophysical crop model EPIC to determine yields and erosion rates for cassava, corn, rapeseed, soybean, sugarcane, sunflower, and wheat under subsistence, rainfed with fertilizer, and high input (irrigation and fertilizer) farming. Yields varied considerably and contributed to variation in CFs to the same extent as erosion rates. Variation in CFs was mainly attributable to geographic location. Crop type and management scenario still lead to variation in CFs of 2 orders of magnitude, and a factor of 6, respectively. Lowest CFs were predicted for sugarcane worldwide, while largest impacts were seen for rapeseed. Largest median CFs were predicted for subsistence farming, while smallest CFs were obtained for high input systems. Median estimated damage in 2014 erosion costs ranged from 0.5 $/t sugarcane to 526 $/t rapeseed. Farmers can minimize erosion by carefully selecting management strategies, while purchasers can carefully select source locations to help reduce erosion related environmental damage. [ABSTRACT FROM AUTHOR]