Land use?related Changes in Aboveground Carbon Stocks of Austria?s Terrestrial Ecosystems

Abstract

Land-use changes considerably alter the patterns and processes of terrestrial ecosystems. In an attempt to assess the impact of the human domination of ecosystems, this study quantifies the effect of human activities on aboveground carbon stocks in vegetation, based on a comparison of potential and actual vegetation in Austria. Following an accounting approach, statistical and GIS data on vegetation, elevation, land use, biomass harvest, as well as forest inventories and real estate statistics, were entered into the assessment, which was performed at the level of municipalities (n = 2,350). The results show that aboveground carbon storage in Austria has been considerably reduced by human activities. Actual vegetation contains 64% less carbon than would be expected in potential vegetation. The conversion of forests to cropland, grasslands, and urban areas has contributed 77% to this reduction in carbon stocks, the remaining 23% is due to forest management. In Austria, aboveground carbon stocks in forests have been reduced by 30% due to reductions in stand age and changes in forest species composition. Placing the data in a historical context, this analysis suggests that the current terrestrial carbon sink is a reversal of past carbon losses.