title: Assessing the influence of historic net and gross land changes on the carbon fluxes of Europe.
abstract: Legacy effects of land cover/use on carbon fluxes require considering both present and past land cover/use change dynamics. To assess past land use dynamics, model-based reconstructions of historic land cover/use are needed. Most historic reconstructions consider only the net area difference between two time steps (net changes) instead of accounting for all area gains and losses (gross changes). Studies about the impact of gross and net land change accounting methods on the carbon balance are still lacking. In this study, we assessed historic changes in carbon in soils for five land cover/use types and of carbon in above-ground biomass of forests. The assessment focused on Europe for the period 1950 to 2010 with decadal time steps at 1-km spatial resolution using a bookkeeping approach. To assess the implications of gross land change data, we also used net land changes for comparison. Main contributors to carbon sequestration between 1950 and 2010 were afforestation and cropland abandonment leading to 14.6 PgC sequestered carbon (of which 7.6 PgC was in forest biomass). Sequestration was highest for old-growth forest areas. A sequestration dip was reached during the 1970s due to changes in forest management practices. Main contributors to carbon emissions were deforestation (1.7 PgC) and stable cropland areas on peaty soils (0.8 PgC). In total, net fluxes summed up to 203 TgC yr(-1) (98 TgC yr(-1) in forest biomass and 105 TgC yr(-1) in soils). For areas that were subject to land changes in both reconstructions (35% of total area), the differences in carbon fluxes were about 68%. Overall for Europe the difference between accounting for either gross or net land changes led to 7% difference (up to 11% per decade) in carbon fluxes with systematically higher fluxes for gross land change data.
authors.affiliation: Environmental Geography, Department of Earth Science, VU University Amsterdam, De Boelelaan, 1081 HV, Amsterdam, The Netherlands.|Laboratory of Geoinformation Science and Remote Sensing, Wageningen University, Droevendaalsesteeg 3, 6708PB, Wageningen, The Netherlands.
authors.forename: Richard
authors.initials: R
authors.lastname: Fuchs
authors.affiliation: Environmental Geography, Department of Earth Science, VU University Amsterdam, De Boelelaan, 1081 HV, Amsterdam, The Netherlands.
authors.forename: Catharina J E
authors.initials: CJ
authors.lastname: Schulp
authors.affiliation: Vegetation, Forest and Landscape Ecology, Alterra, Wageningen UR, Dorevendaalsesteeg 3, 6708PB, Wageningen, The Netherlands.
authors.forename: Geerten M
authors.initials: GM
authors.lastname: Hengeveld
authors.affiliation: Environmental Geography, Department of Earth Science, VU University Amsterdam, De Boelelaan, 1081 HV, Amsterdam, The Netherlands.
authors.forename: Peter H
authors.initials: PH
authors.lastname: Verburg
authors.affiliation: Laboratory of Geoinformation Science and Remote Sensing, Wageningen University, Droevendaalsesteeg 3, 6708PB, Wageningen, The Netherlands.
authors.forename: Jan G P W
authors.initials: JG
authors.lastname: Clevers
authors.affiliation: Vegetation, Forest and Landscape Ecology, Alterra, Wageningen UR, Dorevendaalsesteeg 3, 6708PB, Wageningen, The Netherlands.
authors.forename: Mart-Jan
authors.initials: MJ
authors.lastname: Schelhaas
authors.affiliation: Laboratory of Geoinformation Science and Remote Sensing, Wageningen University, Droevendaalsesteeg 3, 6708PB, Wageningen, The Netherlands.
authors.forename: Martin
authors.initials: M
authors.lastname: Herold
mesh_terms: D002244:Carbon / Q000032:analysis; D057486:Carbon Cycle; D003247:Conservation of Natural Resources; D005060:Europe; D065928:Forests
chemical_list: D002244:Carbon
keywords: carbon budget; carbon sequestration; data driven; historic land dynamic assessment; historical ecology; land cover; land use; soil organic carbon