Articles | Volume 7, issue 3
Research article
15 Sep 2016
Research article |  | 15 Sep 2016

Impacts of land-use history on the recovery of ecosystems after agricultural abandonment

Andreas Krause, Thomas A. M. Pugh, Anita D. Bayer, Mats Lindeskog, and Almut Arneth

Abstract. Land-use changes have been shown to have large effects on climate and biogeochemical cycles, but so far most studies have focused on the effects of conversion of natural vegetation to croplands and pastures. By contrast, relatively little is known about the long-term influence of past agriculture on vegetation regrowth and carbon sequestration following land abandonment. We used the LPJ-GUESS dynamic vegetation model to study the legacy effects of different land-use histories (in terms of type and duration) across a range of ecosystems. To this end, we performed six idealized simulations for Europe and Africa in which we made a transition from natural vegetation to either pasture or cropland, followed by a transition back to natural vegetation after 20, 60 or 100 years. The simulations identified substantial differences in recovery trajectories of four key variables (vegetation composition, vegetation carbon, soil carbon, net biome productivity) after agricultural cessation. Vegetation carbon and composition typically recovered faster than soil carbon in subtropical, temperate and boreal regions, and vice versa in the tropics. While the effects of different land-use histories on recovery periods of soil carbon stocks often differed by centuries across our simulations, differences in recovery times across simulations were typically small for net biome productivity (a few decades) and modest for vegetation carbon and composition (several decades). Spatially, we found the greatest sensitivity of recovery times to prior land use in boreal forests and subtropical grasslands, where post-agricultural productivity was strongly affected by prior land management. Our results suggest that land-use history is a relevant factor affecting ecosystems long after agricultural cessation, and it should be considered not only when assessing historical or future changes in simulations of the terrestrial carbon cycle but also when establishing long-term monitoring networks and interpreting data derived therefrom, including analysis of a broad range of ecosystem properties or local climate effects related to land cover changes.

Short summary
We used a vegetation model to study the legacy effects of different land-use histories on ecosystem recovery in a range of environmental conditions. We found that recovery trajectories are crucially influenced by type and duration of former agricultural land use, especially for soil carbon. Spatially, we found the greatest sensitivity to land-use history in boreal forests and subtropical grasslands. These results are relevant for measurements, climate modeling and afforestation projects.
Final-revised paper