Bacterial and fungal community structure in tundra and mountain birch forest soils after two decades of experimental warming. Impact of long-term warming on microbial communities in subarctic ecosystems

Arctic ecosystems are undergoing drastic changes due to climate change. Expansion and increased plant growth (“Arctic greening”) leading to increased carbon and nutrient pools to soil as well as increased decomposition rates of stored organic matter are predicted to turn the Arctic soils from carbon sinks to carbon sources. However, forecasting the direct and indirect effects of global climate change are challenged by our poor understanding of the soil microbial communities and drivers that affect the community structure and activities. We characterized bacterial and fungal communities in litter, organic and mineral soil layers in tundra and mountain birch forest soils exposed to two decatal experimental warming in northern Fennoscandia (Abisko, Sweden).