The Changing Arctic Ocean Seafloor (ChAOS) - how changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems
The Changing Arctic Ocean Seafloor (ChAOS) project is a £2.1 million, four year (2017-2021) research programme funded by the Natural Environment Research Council (NERC) as part of the Changing Arctic Ocean (CAO) programme. The ChAOS project aims to quantify the effect of changing sea ice cover on organic matter quality, benthic biodiversity, biological transformations of carbon and nutrient pools, and resulting ecosystem function at the Arctic Ocean seafloor. The focal region is a N-S transect along 30°E in the Barents Sea.
Changes in sea ice are resulting in longer more extensive open water conditions which will prolong the growing season, influence primary production and the amount of organic matter reaching the sea floor. This results in a number of questions for the project:
- How will changes in the surface ocean influence seafloor processes?
- What are the consequences of this for carbon sequestration in seafloor sediments?
- How will seafloor biota respond to changes in food quantity and quality?
- Will there be changes to benthic ecosystem services, for example, the recycling of nutrients to overlying waters?
Further information can be found on the Changing Arctic Ocean ChAOS webpage.
Participants
There are nine organisations involved in the ChAOS project, these are:
- University of Leeds
- British Antarctic Survey (BAS)
- University of Newcastle
- University of Bristol
- University of Southampton
- Plymouth Marine Laboratory (PML)
- Durham University
- Université Libre de Bruxelles
- University of Edinburgh
In addition to these core organisations, there are 21 international collaborators involved in the project.
Research Details
The project consists of a detailed study of representative Arctic shelf sea habitats that intersect the ice edge with broad-scale in situ validation studies, shipboard experiments and manipulative laboratory experiments. The project also analyses highly spatially and temporally resolved data obtained by the Canadian, Norwegian and German Arctic programmes and integrates new understanding of controls and effects on biodiversity, biogeochemical pathways and nutrient cycles into modelling approaches.
The objectives of the project are to:
- Quantify the total amount and macronutrient stoichiometry of organic matter delivered to the Arctic seafloor, its source, bioavailability, age, and its fate below the sediment-water interface.
- Characterise the structure, activity and associated functioning of benthic infaunal assemblages under different ice cover scenarios.
- Experimentally determine how the benthic community structure, biogeochemical processes, and other ecosystem functions might change in a future, more ice free and warmer Arctic shelf.
- Analyse and monitor the amount and speciation of carbon and nutrient species recycled from the sediment into the water column under changing environmental conditions as induced by different sea ice scenarios.
- Provide data for improved modelling parameterisation of benthic carbon and nutrient cycling to allow for more reliable predictive tools of changes to Arctic Ocean benthic biological and biogeochemical processes and functions under future climate scenarios.
Fieldwork and Data Collection
The fieldwork will be primarily conducted onboard the NERC research vessel RRS James Clark Ross during the summer months of 2017, 2018 and 2019. The fieldwork will consist of extensive and multi-disciplinary sediment investigations and sampling using a variety of instrumentation and sampling devices such as trawls, boxcorer, megacorer at five benthic stations on a transect along 30°E that are variably influenced by winter sea ice cover. Additional cruises to locations that share similar sediment and water conditions in Norway and Canada will also be completed by international partners.
From the analyses of the field samples and data obtained by international partners, a range of well-constrained laboratory experiments will be conducted to collect further data. The experiments will expose incubated natural sediment to environmental conditions that are most likely to vary in response to changing sea ice cover and analyse the response of biology and biogeochemistry to these changes in present versus future environments.
These datasets will be complemented further by existing data provided by international partners in Norway, Canada, USA, Italy, Poland and Germany.
