Two Decades of Experimental Manipulations of Heaths and Forest Understory in the Subarctic
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Current atmospheric warming due to increase of greenhouse gases will have severe consequences for the structure and functioning of arctic ecosystems with changes that, in turn, may feed back on the global-scale composition of the atmosphere. During more than two decades, environmental controls on biological and biogeochemical processes and possible atmospheric feedbacks have been intensely investigated at Abisko, Sweden, by long-term ecosystem manipulations. The research has addressed questions like environmental regulation of plant and microbial community structure and biomass, carbon and nutrient pools and element cycling, including exchange of greenhouse gases and volatile organic compounds, with focus on fundamental processes in the interface between plants, soil and root-associated and free-living soil microorganisms. The ultimate goal has been to infer from these multi-decadal experiments how subarctic and arctic ecosystems will respond to likely environmental changes in the future. Here we give an overview of some of the experiments and main results.
KeywordsTundra Warming Field experiments Plant–microbe interactions Carbon and nitrogen cycling
We are grateful to the staff at the Abisko Scientific Research Station for excellent facilities and support, and to the Director through many years, Prof. Terry V. Callaghan, for his encouragement and enthusiastic work in arctic ecological research. The studies have been supported by multiple grants from The Danish Council for Independent Research. We also wish to thank The Danish National Research Foundation for funding the activities within the Center for Permafrost (CENPERM). Numerous colleagues, students and field assistants are thanked for enthusiastic collaboration during the field and analytical work.
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