Climate Change Effects In High-Latitude Environments: Examples From Northern Sweden
Event Type: Seminar
Event Date: 06 Feb 2018
Venue: ASE 3D Viz Laboratory Room (N2-B1c-16c)
Speaker: Reiner Giesler
About the speaker:
Reiner Giesler is currently a professor at Umeå University, Sweden. His research focuses on biogeochemical processes in terrestrial and aquatic ecosystems with special emphasis climate change effects in Arctic environments. In an on-going project, his team integrates spatial and temporal variation in stream and soil biogeochemical processes to generate knowledge that can be used to better understand how aquatic ecosystems are linked to the terrestrial environment and their potential response to climate change. They focus on catchments with upland soils; these tundra soils are relatively well-drained and often subjected to physical motion induced by frost processes (cryoturbation) and permafrost. A special interest is the influence of weathering as a source of dissolved inorganic carbon in high-latitude streams. Part of Prof Giesler's research is focused on phosphorus (P) dynamics across boreal and arctic landscape gradients with a special focus on organic phosphorus. Specifically, he is interested in how P availability may change with the on-going climate-induced changes in tundra landscapes.
About the event:
Climatic change is currently reshaping Arctic landscapes where enhanced permafrost thawing, arctic greening and shifts in seasonality are all examples of landscape-scale changes that will have regional as well as global consequences. One of the greatest concerns with regards to on-going ecosystem responses to climate change is the potential loss of carbon in the currently frozen permafrost soils; a pool that contains twice as much carbon as there currently is in the atmosphere. In Abisko, northernmost Sweden, research has been on-going for the last 100 years at the Abisko Scientific Research Station. This research has revealed clear climate-related changes in the Abisko region; permafrost affected palsa mires are eroding and have in some cases completely disappeared during the last decades. Further, the winter duration of the ice cover of the largest lake in the region has clearly decreased and there are also indications of upslope tree-line advancement. The ecological and biogeochemical implications of these changes still remain uncertain to a large extent despite a growing body of Arctic climate change research. For example, we are still lacking long-term experimental data that can help us better understand the on-going processes in these rapidly changing environments. In this presentation, I will give a broad overview of climate change effects in the Arctic and discuss some of our results from using natural climate gradients to understand the potential responses ecosystem processes to future climatic changes in the tundra across the region. These study systems encompass elevational gradients across different vegetation types as well as lakes and streams distributed across environmental conditions varying in the same landscape. Elevational gradients represent powerful natural experiments that may inform about community responses to variation in temperature at the landscape scale whenever other abiotic factors remain relatively constant. I will specifically emphasize the need for more integrated research on terrestrial-aquatic interactions and the importance of aquatic ecosystems for landscape carbon losses.
Permafrost - permanently frozen soils where only the upper soil thaw during the summer e.g. the active layer; Palsa – frost-heaved soil/peat; Mire – a wetland type dominated by peat-forming plants.