GC23C-0652:
CARBON POOLS IN A TEMPERATE HEATHLAND RESIST CHANGES IN A FUTURE CLIMATE
Tuesday, 16 December 2014
Per Ambus1, Sabine Reinsch2, Pia L Nielsen3, Anders Michelsen4, Inger K Schmidt3 and Teis N Mikkelsen5, (1)Technical University of Denmark, Chemical Engineering, Kgs. Lyngby, Denmark, (2)Centre for Ecology and Hydrology, Bangor, United Kingdom, (3)Copenhagen University, Department of Geoscience and Natural Resource Management, Copenhagen, Denmark, (4)Copenhagen University, Department of Biology, Copenhagen, Denmark, (5)Technical University of Denmark, Chemical Engineering, Roskilde, Denmark
Abstract:
The fate of recently plant assimilated carbon was followed into ecosystem carbon pools and fluxes in a temperate heathland after a 13CO2 pulse in the early growing season in a 6-year long multi-factorial climate change experiment. Eight days after the pulse, recently assimilated carbon was significantly higher in storage organs (rhizomes) of the grass Deschampsia flexuosa under elevated atmospheric CO2 concentration. Experimental drought induced a pronounced utilization of recently assimilated carbon belowground (roots, microbes, dissolved organic carbon) potentially counterbalancing limited nutrient availability. The fate of recently assimilated carbon was not affected by moderate warming. The full factorial combination of elevated CO2, warming and drought simulating future climatic conditions as expected for Denmark in 2075 did not change short-term carbon turnover significantly compared to ambient conditions. Overall, climate factors interacted in an unexpected way resulting in strong resilience of the heathland in terms of short-term carbon turnover in a future climate.
