Climate warming represents one of the most complex issues of the present time. Soils worldwide harbor the largest terrestrial carbon pool, exceeding the amount of carbon stored in the atmosphere and plant biomass. Microbes are known to play key roles in both soil carbon stabilization and its release into the atmosphere as carbon dioxide or methane. The extent of microbial response to predicted climate change represents a major gap in current knowledge.
Exploration of microbial response to climate manipulation in tundra soils
Climate change is predicted to have the most pronounced effect in northern latitudes. Besides rising temperature, high latitudes are expected to experience increased winter precipitation in the form of snow during the coming decades as a result of climate change. The snow pack serves as an insulation layer for soil and vegetation and increased snow cover thus enhances the isolation effect resulting in higher soil temperature during winter. The project uses experimental sites in South and West Greenland with established snow fences and open top chambers (OTCs) that mimic increased winter precipitation and increased summer warming on tundra ecosystem, respectively. We aim to characterize microbial response to climate manipulation using amplicon sequencing, metatranscriptomics, DNA-stable isotope probing (DNA-SIP) and BONCAT-FACS approaches.
Assessment of the effect of fire on soil microbial community in tundra ecosystem
Wildfires are common ecosystem disturbance in the boreal forests, but until recently they have been relatively rare in Arctic tundra ecosystems. However rapid climate change in high latitudes causing increase of temperature and evapotranspiration have led to higher frequency and intensity of wildfires in Arctic regions. The project uses sites in West Greenland that were treated by fire of various intensity. Analysis of microbiome from the soil collected in different time points after the fire treatment provide information about changes in microbial community and microbial driven processes occurring during ecosystem recovery.
Identification of microbial drivers of shrub expansion in Greenland
Vegetation in Arctic tundra is represented by low-growing plants including several species of woody dwarf shrubs that serve as main carbon fixers in the Arctic ecosystem. Shrub expansion in Arctic represents one of the most dramatic changes in northern latitudes of past decades and is primarily associated with changes in air temperature and soil moisture however there is increasing evidence that other factors are also involved including soil microbial communities. The project investigates soil microbial communities associated with roots of dwarf shrubs collected along southwest, east and north coast of Greenland and their impact on shrub expansion.
The effect of long-term soil warming on microbial community in tundra soil
Increased summer temperatures in cold regions can stimulate the activity of soil microbes and boost their decomposing abilities and potentially increase the production of greenhouse gases. The project uses experimental site in Abisko (Northern Sweden) climate manipulation using open-top chambers. The experimental site was established more than 20 years ago and thus provide opportunity to study the effect of long-term soil warming on microbial communities.
Assessment of the responses of soil microbes to climate manipulations worldwide by meta-analytical synthesis of sequencing data
The global distribution of microbes is affected by temperature and thus potentially sensitive to warming. The effects of warming on soil microbes, however, largely varies with climate regions and ecosystem types. Despite a range of individual experiments examining the response of soil microbes under warming treatments, the effect of warming on microbial communities remains elusive. The project aims to synthesize available microbial sequencing data from manipulative warming experiments to examine the broad-scale responses of fungi and bacteria to warming treatment.
Microbial response to permafrost thaw
Increase in temperature leading to permafrost thaw and decomposition of previously frozen carbon pool that has been accumulating in permafrost for thousands years is considered as a key terrestrial ecosystem feedback to global climate change. Using the samples from permafrost cores collected along transects covering the major landscape types in Svalbard and Siberia, the project aims to determine the key environmental drivers of microbial communities in permafrost soils and changes in microbial communities in response to permafrost thaw.