Effect of Climate change On The Arctic Benthos – ECOTAB

- Task 1: Seasonal variability in pelagic-benthic coupling. This task aims to describe the ecosystem structure and function throughout the entire year in greater details, combining both, pelagic and benthic perspectives. Organic matter fluxes from the water column to the sea floor and the benthic response will be studied as a function of biological and environmental factors by a multi-biomarker approach.
- Task 2: Impact of changes in food quality for the benthos. The goal of this second task is to address experimentally the impact of changes in food sources quality for the benthos. Based on the results from Task 1 and according to various climate change scenarios, intact benthic communities and key bivalve species will be fed with different food sources with different food quality (phytoplankton, ice algae, microphytobenthos, fecal pellets).
- Task 3: Impact of changes in temperature, pH and salinity, on key bivalves species. The Task 3 aims to address experimentally the impact of climate-induced changes in environmental parameters on key bivalves species. For doing so, perturbation experiments will be performed by changing salinity and pH.
- Task 4: Modelisation. This last task aims to better understand i) the energy allocation within the benthic species under different scenarios of food quality and abiotic parameters as temperature, pH and salinity by integrating data obtained from tasks 2 and 3 in a dynamic energy budget model (DEB, based on DEB theory) and ii) the matter fluxes in the coastal Arctic ecosystem by coupling data from task 1, 2, 3.

The following link contains up to date information about the project, in particular about the field work performed this year: www-iuem.univ-brest.fr/ecotab
Although the project recently started, it already permitted to create connections with other projects and researchers with complementary research interests, including the Norwegian funded Cleopatra II project, the team of Thomas Brown (Plymouth, UK), the team of Maria Wlodarska-Kowalczuk (IOPAS, Poland).

Not yet

The first samples obtained in the first missions are starting to be analyzed. Results will permit scientific publication in 2013.

It is now generally admitted that effects of climate change are enhanced in polar areas. Because of the ice-dependent character of Arctic marine ecosystems, climate-induced changes in sea-ice cover are expected to lead to shifts in primary production (decrease of ice algal production, increase in phytoplankton and microphytobenthos production) and changes in sea water chemistry (lower salinity and pH, higher temperature). Those changes will have repercussions on the entire ecosystem functioning and carbon cycling, although it is yet unclear how benthic organisms will respond to those changes in food sources and environmental conditions.

Traditionally, the study of the Arctic Ocean has mainly been carried out by countries surrounding the Arctic Ocean, i.e. Canada, USA, Norway, Denmark and Russia. However, since climate change is felt first and foremost in the Arctic, growing concerns for Arctic ecosystems and native populations living there have brought other countries to join research efforts. In particular France, which carries important polar activities in Antarctica, recently started to extend its polar marine ecosystem research efforts to the Arctic, with new projects and with the creation of an International Research Unit of the CNRS in Québec.

Although recent Arctic ecosystem studies have focused on describing the present state of either the "pelagic" or "benthic" compartment, the link between those two compartments, the "pelagic-benthic" coupling has often been underestimated. Moreover very few studies have included experimental approach in order to predict future scenarios, while this knowledge is crucial if we are to understand possible future changes and create models.

The overarching goal of this study is to investigate how climate-induced changes in biological (food sources) and environmental conditions will impact the Arctic benthos. This project will combine existing data, new field data, and a new experimental approach which will test various scenarios of food (i.e. high food quality, low food quality) and environmental parameters (pH, salinity, temperature) therefore improving understanding of present state Arctic coastal ecosystem function, and prediction of possible feedback scenarios of the ecosystem to changes in a less ice-rich Arctic due to climate warming. The work will be separated in 4 tasks:
- Description in great details of the seasonal variability in pelagic-benthic coupling, combining both pelagic and benthic perspectives
- Study experimentally the impact of changes in food quality for the benthos
- Study experimentally the impact of changes in temperature, pH and salinity, on key bivalves species
- Development and calibration of models of carbon and energy fluxes in the ecosystem and in the key bivalves species

This project will take place at the French/German research station in Ny-Alesund, Svalbard, which will provide adequate set up and background data insuring its success.

In addition to its scientific goals, this project aims to create international sustainable collaborations between France, Norway, Germany and Canada so experts can bring and share their expertise for a better understanding of the whole Arctic ecosystem functioning. In particular, this project will be held in tight collaboration with the French project Apolobis, aiming to establish an Arctic observatory based on bivalves in Ny-Alesund, and the Norwegian project Icicles, aiming to understand effect of climate change on key zooplanktonic organisms.