Global bioenergy potentials of degraded lands

Abstract

Biomass production for energy may serve to mitigate climate change. However, using productive lands for bioenergy production may result in carbon debts, biodiversity losses and competition with food production. Using degraded lands, characterized by a reduced agricultural productivity, can serve to avoid theses issues, to achieve more green house gas reduction by storing carbon in the soil and to mitigate soil degradation. However, up-to date no detailed studies were available on the global bioenergy potentials of degraded lands. Therefore, we assessed the potential, i.e. the upper limit, of global bioenergy production on degraded lands that were not classified as forest, cropland, pastoral land or urban area. Geographically explicit degradation information downscaled to a 5 minute grid was used and the current land use of degraded lands was examined. Potential yields of perennial energy crops based on soil and climate were used and yield reductions were applied based on perennial energy crops, specific for different types and degrees of degradation. Results showed a potential of 32-42 EJ/yr of dergaded lands that were not in use as forest, cropland, pastoral land or urban area, Bioenergy production on these lands comprises a promising option in the light of sustainable development.