A changing Arctic – What will future Arctic look like?
Permafrost is thawing at an extraordinary rate with rising temperatures in the Arctic. Climate change is closely linked with alteration of species composition and loss of biodiversity. This holds for plants, animals, and microorganisms. Permafrost thaw will expose large amount of nitrogen (N) and carbon (C) to microbial decomposition with strong implications for climate gas emission into the atmosphere. Presently, there is a large knowledge gap on the effects of climate change during the cold season on permafrost thaw. There is also a great urgency to understand how climate change will combine with the action of other important drivers of change. The frequency of extreme weather events is also increasing. The permafrost is covering 37% of the northern hemisphere and contains around 1/3 of the Earths carbon deposits. These carbon deposits are locked in the frozen Arctic tundra. Mosses, which often cover the entire soil surface in the Arctic, exert a strong control on soil temperature and moisture by keeping Arctic soils constantly cold and wet. Increasing temperatures and herbivore pressure will led to a reduction in the moss layer and its insulation effect and thus stimulate microbial activity and release large amounts of the greenhouse gases CO2 and CH4 into the atmosphere. TERRA aims to study the interactive effects of warming during the cold season and increased herbivory on permafrost thaw and the cascading effects on N and C cycling in the High Arctic. To achieve this, we will conduct field experiment in the High Arctic tundra of Svalbard, where spring and autumn warming, strong winter rainfall and goose grubbing are manipulated. Combining new field techniques and state-of-the-art chemical and DNA-based measurements, TERRA will investigate plants, soil animals, and microorganisms and how the experimental manipulations affect them. This will allow us to gain a holistic understanding of permafrost responses to climate change.
Permafrost is thawing at an unprecedented rate with rising temperatures in the Arctic. Permafrost thaw will expose large amount of nitrogen (N) and carbon (C) to microbial decomposition with strong implications for C emission into the atmosphere. Presently, there is a large knowledge gap on the effects of climate change during the cold season on permafrost thaw. There is also a great urgency to understand how climate change will combine with the action of other important drivers of change.
TERRA aims to study the interactive effects of warming during the cold season and increased herbivory on permafrost thaw and cascading effects on N and C cycling in the High Arctic.
We will set up a novel field experiment in the High Arctic tundra of Svalbard, where spring and autumn warming, strong winter rainfall and goose grubbing are manipulated. Combining new field techniques and state-of-the-art chemical and DNA-based measurements, TERRA will investigate how the experimental manipulations affect (1) permafrost thaw depth (2) soil organic C degradation and N mineralization; (3) root-associated organisms in relation to their role in plant uptake and soil C sequestration and (4) microbial diversity and function in relation to C emission and soil N transformations.
Our project faces challenges linked to the proposed experimental manipulations, the planned studies, and the complexity of year-round field work in the Arctic. The success of the project is guaranteed by the involvement of an interdisciplinary team of world-leading arctic researchers, the excellence of the research facilities, field logistic and infrastructure available to the team, and the high quality of the project organization.
TERRA will increase significantly our understanding of biogeochemical cycles in thawing permafrost under two of the largest threats to High Arctic ecosystems. The results will be of a global importance and relevant to the scientific community, stakeholders and to the public.