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James K, Macreadie PI, Burdett HL, Davies I, Kamenos NA. It's time to broaden what we consider a 'blue carbon ecosystem'. GLOBAL CHANGE BIOLOGY 2024; 30:e17261. [PMID: 38712641 DOI: 10.1111/gcb.17261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 01/10/2024] [Accepted: 02/18/2024] [Indexed: 05/08/2024]
Abstract
Photoautotrophic marine ecosystems can lock up organic carbon in their biomass and the associated organic sediments they trap over millennia and are thus regarded as blue carbon ecosystems. Because of the ability of marine ecosystems to lock up organic carbon for millennia, blue carbon is receiving much attention within the United Nations' 2030 Agenda for Sustainable Development as a nature-based solution (NBS) to climate change, but classically still focuses on seagrass meadows, mangrove forests, and tidal marshes. However, other coastal ecosystems could also be important for blue carbon storage, but remain largely neglected in both carbon cycling budgets and NBS strategic planning. Using a meta-analysis of 253 research publications, we identify other coastal ecosystems-including mud flats, fjords, coralline algal (rhodolith) beds, and some components or coral reef systems-with a strong capacity to act as blue carbon sinks in certain situations. Features that promote blue carbon burial within these 'non-classical' blue carbon ecosystems included: (1) balancing of carbon release by calcification via carbon uptake at the individual and ecosystem levels; (2) high rates of allochthonous organic carbon supply because of high particle trapping capacity; (3) high rates of carbon preservation and low remineralization rates; and (4) location in depositional environments. Some of these features are context-dependent, meaning that these ecosystems were blue carbon sinks in some locations, but not others. Therefore, we provide a universal framework that can evaluate the likelihood of a given ecosystem to behave as a blue carbon sink for a given context. Overall, this paper seeks to encourage consideration of non-classical blue carbon ecosystems within NBS strategies, allowing more complete blue carbon accounting.
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Affiliation(s)
| | - Peter I Macreadie
- Marine Research and Innovation Centre, School of Life and Environmental Sciences, Deakin University, Burwood, Victoria, Australia
| | - Heidi L Burdett
- Umeå Marine Sciences Centre, Umeå University, Norrbyn, Sweden
- Department of Ecology and Environmental Sciences, Umeå University, Umeå, Sweden
| | | | - Nicholas A Kamenos
- Umeå Marine Sciences Centre, Umeå University, Norrbyn, Sweden
- Department of Ecology and Environmental Sciences, Umeå University, Umeå, Sweden
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Antarctic Seabed Assemblages in an Ice-Shelf-Adjacent Polynya, Western Weddell Sea. BIOLOGY 2022; 11:biology11121705. [PMID: 36552215 PMCID: PMC9774262 DOI: 10.3390/biology11121705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/18/2022] [Accepted: 11/21/2022] [Indexed: 11/29/2022]
Abstract
Ice shelves cover ~1.6 million km2 of the Antarctic continental shelf and are sensitive indicators of climate change. With ice-shelf retreat, aphotic marine environments transform into new open-water spaces of photo-induced primary production and associated organic matter export to the benthos. Predicting how Antarctic seafloor assemblages may develop following ice-shelf loss requires knowledge of assemblages bordering the ice-shelf margins, which are relatively undocumented. This study investigated seafloor assemblages, by taxa and functional groups, in a coastal polynya adjacent to the Larsen C Ice Shelf front, western Weddell Sea. The study area is rarely accessed, at the frontline of climate change, and located within a CCAMLR-proposed international marine protected area. Four sites, ~1 to 16 km from the ice-shelf front, were explored for megabenthic assemblages, and potential environmental drivers of assemblage structures were assessed. Faunal density increased with distance from the ice shelf, with epifaunal deposit-feeders a surrogate for overall density trends. Faunal richness did not exhibit a significant pattern with distance from the ice shelf and was most variable at sites closest to the ice-shelf front. Faunal assemblages significantly differed in composition among sites, and those nearest to the ice shelf were the most dissimilar; however, ice-shelf proximity did not emerge as a significant driver of assemblage structure. Overall, the study found a biologically-diverse and complex seafloor environment close to an ice-shelf front and provides ecological baselines for monitoring benthic ecosystem responses to environmental change, supporting marine management.
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Shin Y, Midgley GF, Archer ERM, Arneth A, Barnes DKA, Chan L, Hashimoto S, Hoegh‐Guldberg O, Insarov G, Leadley P, Levin LA, Ngo HT, Pandit R, Pires APF, Pörtner H, Rogers AD, Scholes RJ, Settele J, Smith P. Actions to halt biodiversity loss generally benefit the climate. GLOBAL CHANGE BIOLOGY 2022; 28:2846-2874. [PMID: 35098619 PMCID: PMC9303674 DOI: 10.1111/gcb.16109] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 01/07/2022] [Accepted: 01/11/2022] [Indexed: 05/04/2023]
Abstract
The two most urgent and interlinked environmental challenges humanity faces are climate change and biodiversity loss. We are entering a pivotal decade for both the international biodiversity and climate change agendas with the sharpening of ambitious strategies and targets by the Convention on Biological Diversity and the United Nations Framework Convention on Climate Change. Within their respective Conventions, the biodiversity and climate interlinked challenges have largely been addressed separately. There is evidence that conservation actions that halt, slow or reverse biodiversity loss can simultaneously slow anthropogenic mediated climate change significantly. This review highlights conservation actions which have the largest potential for mitigation of climate change. We note that conservation actions have mainly synergistic benefits and few antagonistic trade-offs with climate change mitigation. Specifically, we identify direct co-benefits in 14 out of the 21 action targets of the draft post-2020 global biodiversity framework of the Convention on Biological Diversity, notwithstanding the many indirect links that can also support both biodiversity conservation and climate change mitigation. These relationships are context and scale-dependent; therefore, we showcase examples of local biodiversity conservation actions that can be incentivized, guided and prioritized by global objectives and targets. The close interlinkages between biodiversity, climate change mitigation, other nature's contributions to people and good quality of life are seldom as integrated as they should be in management and policy. This review aims to re-emphasize the vital relationships between biodiversity conservation actions and climate change mitigation in a timely manner, in support to major Conferences of Parties that are about to negotiate strategic frameworks and international goals for the decades to come.
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Affiliation(s)
| | - Guy F. Midgley
- School for Climate Studies, Department of Botany and ZoologyStellenbosch UniversityStellenboschSouth Africa
| | - Emma R. M. Archer
- Department of GeographyGeo‐Informatics and MeteorologyUniversity of PretoriaHatfield, PretoriaSouth Africa
| | - Almut Arneth
- Atmospheric Environmental ResearchKarlsruhe Institute of Technology (KIT)Garmisch‐PartenkirchenGermany
| | | | - Lena Chan
- International Biodiversity Conservation DivisionNational Parks BoardSingaporeSingapore
| | | | - Ove Hoegh‐Guldberg
- School of Biological Sciences and ARC Centre of Excellence for Coral Reef StudiesThe University of QueenslandBrisbaneQueenslandAustralia
| | - Gregory Insarov
- Institute of Geography of the Russian Academy for SciencesMoscowRussia
| | - Paul Leadley
- Laboratoire d’Ecologie Systématique EvolutionUniversité Paris‐Saclay, CNRS, AgroParisTechOrsayFrance
| | - Lisa A. Levin
- Center for Marine Biodiversity and Conservation and Integrative Oceanography DivisionScripps Institution of OceanographyUniversity of CaliforniaSan DiegoCaliforniaUSA
| | - Hien T. Ngo
- Office of Climate Change, Biodiversity and Environment, Food and Agriculture Organization of the United NationsRomeItaly
- Intergovernmental Science‐Policy Platform on Biodiversity and Ecosystem Services (IPBES)BonnGermany
| | - Ram Pandit
- Centre for Environmental Economics and PolicyUWA School of Agriculture and EnvironmentThe University of Western AustraliaCrawleyWestern AustraliaAustralia
- Global Center for Food, Land and Water ResourcesResearch Faculty of AgricultureHokkaido UniversitySapporoHokkaidoJapan
| | - Aliny P. F. Pires
- Department of Ecology – IBRAGRio de Janeiro State University (UERJ)Rio de JaneiroBrazil
| | - Hans‐Otto Pörtner
- Alfred Wegener Institute for Polar and Marine ResearchBremerhavenGermany
| | | | - Robert J. Scholes
- Global Change InstituteUniversity of the WitwatersrandJohannesburgSouth Africa
| | - Josef Settele
- Department of Conservation Biology and Social‐Ecological SystemsHelmholtz Centre for Environmental Research—UFZHalleGermany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐LeipzigLeipzigGermany
| | - Pete Smith
- Institute of Biological and Environmental SciencesUniversity of AberdeenAberdeenUK
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Benthic Biodiversity, Carbon Storage and the Potential for Increasing Negative Feedbacks on Climate Change in Shallow Waters of the Antarctic Peninsula. BIOLOGY 2022; 11:biology11020320. [PMID: 35205187 PMCID: PMC8869673 DOI: 10.3390/biology11020320] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 02/10/2022] [Accepted: 02/14/2022] [Indexed: 02/04/2023]
Abstract
The importance of cold-water blue carbon as biological carbon pumps that sequester carbon into ocean sediments is now being realised. Most polar blue carbon research to date has focussed on deep water, yet the highest productivity is in the shallows. This study measured the functional biodiversity and carbon standing stock accumulated by shallow-water (<25 m) benthic assemblages on both hard and soft substrata on the Antarctic Peninsula (WAP, 67° S). Soft substrata benthic assemblages (391 ± 499 t C km-2) contained 60% less carbon than hard substrata benthic assemblages (648 ± 909). In situ observations of substrata by SCUBA divers provided estimates of 59% hard (4700 km) and 12% soft (960 km) substrata on seasonally ice-free shores of the Antarctic Peninsula, giving an estimate of 253,000 t C at 20 m depth, with a sequestration potential of ~4500 t C year-1. Currently, 54% of the shoreline is permanently ice covered and so climate-mediated ice loss along the Peninsula is predicted to more than double this carbon sink. The steep fjordic shorelines make these assemblages a globally important pathway to sequestration, acting as one of the few negative (mitigating) feedbacks to climate change. The proposed WAP marine protected area could safeguard this ecosystem service, helping to tackle the climate and biodiversity crises.
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März C, Freitas FS, Faust JC, Godbold JA, Henley SF, Tessin AC, Abbott GD, Airs R, Arndt S, Barnes DKA, Grange LJ, Gray ND, Head IM, Hendry KR, Hilton RG, Reed AJ, Rühl S, Solan M, Souster TA, Stevenson MA, Tait K, Ward J, Widdicombe S. Biogeochemical consequences of a changing Arctic shelf seafloor ecosystem. AMBIO 2022; 51:370-382. [PMID: 34628602 PMCID: PMC8692578 DOI: 10.1007/s13280-021-01638-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 09/02/2021] [Accepted: 09/22/2021] [Indexed: 05/05/2023]
Abstract
Unprecedented and dramatic transformations are occurring in the Arctic in response to climate change, but academic, public, and political discourse has disproportionately focussed on the most visible and direct aspects of change, including sea ice melt, permafrost thaw, the fate of charismatic megafauna, and the expansion of fisheries. Such narratives disregard the importance of less visible and indirect processes and, in particular, miss the substantive contribution of the shelf seafloor in regulating nutrients and sequestering carbon. Here, we summarise the biogeochemical functioning of the Arctic shelf seafloor before considering how climate change and regional adjustments to human activities may alter its biogeochemical and ecological dynamics, including ecosystem function, carbon burial, or nutrient recycling. We highlight the importance of the Arctic benthic system in mitigating climatic and anthropogenic change and, with a focus on the Barents Sea, offer some observations and our perspectives on future management and policy.
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Affiliation(s)
- Christian März
- School of Earth and Environment, University of Leeds, Leeds, LS2 9JT UK
| | - Felipe S. Freitas
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol, BS8 1QE UK
| | - Johan C. Faust
- School of Earth and Environment, University of Leeds, Leeds, LS2 9JT UK
- MARUM—Center for Marine Environmental Sciences, University of Bremen, Leobener Strasse 8, 28359 Bremen, Germany
| | - Jasmin A. Godbold
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton, SO14 3ZH UK
| | - Sian F. Henley
- School of GeoSciences, University of Edinburgh, James Hutton Road, Edinburgh, EH9 3FE UK
| | - Allyson C. Tessin
- Department of Geology, Kent State University, 221 McGilvrey Hall, 325 S. Lincoln St., Kent, OH 44242 USA
| | - Geoffrey D. Abbott
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU UK
| | - Ruth Airs
- Plymouth Marine Laboratory, Prospect Place, Plymouth, PL1 3DH UK
| | - Sandra Arndt
- Department of Geosciences, Environment and Society, Université libre de Bruxelles, Brussels, Av. F.
Roosevelt 50, CP160/02, 1050 Brussels, Belgium
| | - David K. A. Barnes
- British Antarctic Survey, UKRI, High Cross, Maddingley Rd, Cambridge, CB3 0ET UK
| | - Laura J. Grange
- School of Ocean Sciences, Bangor University, Bangor, Gwynedd, LL57 2DG North Wales UK
| | - Neil D. Gray
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU UK
| | - Ian M. Head
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU UK
| | - Katharine R. Hendry
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol, BS8 1QE UK
| | - Robert G. Hilton
- Department of Geography, Durham University, Lower Mountjoy, South Rd, Durham, DH1 3LE USA
| | - Adam J. Reed
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton, SO14 3ZH UK
| | - Saskia Rühl
- Plymouth Marine Laboratory, Prospect Place, Plymouth, PL1 3DH UK
- Helmholtz Zentrum Hereon, Max-Planck-Straße 1, 21502 Geesthacht, Germany
| | - Martin Solan
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton, SO14 3ZH UK
| | - Terri A. Souster
- British Antarctic Survey, UKRI, High Cross, Maddingley Rd, Cambridge, CB3 0ET UK
- Department of Biosciences, Fisheries and Economics, UIT, Tromsø, Norway
| | - Mark A. Stevenson
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU UK
- Department of Geography, Durham University, Lower Mountjoy, South Rd, Durham, DH1 3LE USA
| | - Karen Tait
- Plymouth Marine Laboratory, Prospect Place, Plymouth, PL1 3DH UK
| | - James Ward
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol, BS8 1QE UK
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Climate Mitigation through Biological Conservation: Extensive and Valuable Blue Carbon Natural Capital in Tristan da Cunha's Giant Marine Protected Zone. BIOLOGY 2021; 10:biology10121339. [PMID: 34943254 PMCID: PMC8698552 DOI: 10.3390/biology10121339] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/07/2021] [Accepted: 12/09/2021] [Indexed: 11/17/2022]
Abstract
Simple Summary Solving biodiversity loss and climate change are part of the same problem; intact natural habitats can provide powerful and efficient climate mitigation if protected. Beyond the land (forests), there is little appreciation of just how important ocean nature is to climate mitigation. Carbon captured, stored and the rate at which it is buried (sequestration) by marine organisms is called blue carbon. We measured how much blue carbon occurs around the remote islands and seamounts of the Tristan da Cunha archipelago Marine Protected Zone (MPZ). We estimated that there are 300 tonnes of carbon (tC) captured in seaweed biomass each year, a proportion of which will sink and become a part of the long-term sediment carbon store. In deeper water we found a standing stock of ~2.3 million tC in the shallowest 1000 m depths, of which equivalent to 0.8 million t of carbon dioxide has the potential to be sequestered. At current carbon prices, and were it to attract blue carbon credits, £24 million worth of blue carbon can potentially be sequestered from the standing stock of this small United Kingdom Overseas Territory. This standing stock is protected and growth could, therefore, generate an additional £3.5 million worth of sequestered carbon a year, making it an unrecognized major component of the local economy. The economic return on this example MPZ probably ranks highly amongst climate mitigation schemes. The message is that placing meaningful protection to carbon-rich natural habitats can massively help society fight climate change and biodiversity loss. Nations who provide this protection should be fairly compensated, particularly where it comes at the detriment of other economic uses of marine habitats. Abstract Carbon-rich habitats can provide powerful climate mitigation if meaningful protection is put in place. We attempted to quantify this around the Tristan da Cunha archipelago Marine Protected Area. Its shallows (<1000 m depth) are varied and productive. The 5.4 km2 of kelp stores ~60 tonnes of carbon (tC) and may export ~240 tC into surrounding depths. In deep-waters we analysed seabed data collected from three research cruises, including seabed mapping, camera imagery, seabed oceanography and benthic samples from mini-Agassiz trawl. Rich biological assemblages on seamounts significantly differed to the islands and carbon storage had complex drivers. We estimate ~2.3 million tC are stored in benthic biodiversity of waters <1000 m, which includes >0.22 million tC that can be sequestered (the proportion of the carbon captured that is expected to become buried in sediment or locked away in skeletal tissue for at least 100 years). Much of this carbon is captured by cold-water coral reefs as a mixture of inorganic (largely calcium carbonate) and organic compounds. As part of its 2020 Marine Protection Strategy, these deep-water reef systems are now protected by a full bottom-trawling ban throughout Tristan da Cunha and representative no take areas on its seamounts. This small United Kingdom Overseas Territory’s reef systems represent approximately 0.8 Mt CO2 equivalent sequestered carbon; valued at >£24 Million GBP (at the UN shadow price of carbon). Annual productivity of this protected standing stock generates an estimated £3 million worth of sequestered carbon a year, making it an unrecognized and potentially major component of the economy of small island nations like Tristan da Cunha. Conservation of near intact habitats are expected to provide strong climate and biodiversity returns, which are exemplified by this MPA.
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Societal importance of Antarctic negative feedbacks on climate change: blue carbon gains from sea ice, ice shelf and glacier losses. Naturwissenschaften 2021; 108:43. [PMID: 34491425 PMCID: PMC8423686 DOI: 10.1007/s00114-021-01748-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/26/2021] [Accepted: 08/09/2021] [Indexed: 11/29/2022]
Abstract
Diminishing prospects for environmental preservation under climate change are intensifying efforts to boost capture, storage and sequestration (long-term burial) of carbon. However, as Earth’s biological carbon sinks also shrink, remediation has become a key part of the narrative for terrestrial ecosystems. In contrast, blue carbon on polar continental shelves have stronger pathways to sequestration and have increased with climate-forced marine ice losses—becoming the largest known natural negative feedback on climate change. Here we explore the size and complex dynamics of blue carbon gains with spatiotemporal changes in sea ice (60–100 MtCyear−1), ice shelves (4–40 MtCyear−1 = giant iceberg generation) and glacier retreat (< 1 MtCyear−1). Estimates suggest that, amongst these, reduced duration of seasonal sea ice is most important. Decreasing sea ice extent drives longer (not necessarily larger biomass) smaller cell-sized phytoplankton blooms, increasing growth of many primary consumers and benthic carbon storage—where sequestration chances are maximal. However, sea ice losses also create positive feedbacks in shallow waters through increased iceberg movement and scouring of benthos. Unlike loss of sea ice, which enhances existing sinks, ice shelf losses generate brand new carbon sinks both where giant icebergs were, and in their wake. These also generate small positive feedbacks from scouring, minimised by repeat scouring at biodiversity hotspots. Blue carbon change from glacier retreat has been least well quantified, and although emerging fjords are small areas, they have high storage-sequestration conversion efficiencies, whilst blue carbon in polar waters faces many diverse and complex stressors. The identity of these are known (e.g. fishing, warming, ocean acidification, non-indigenous species and plastic pollution) but not their magnitude of impact. In order to mediate multiple stressors, research should focus on wider verification of blue carbon gains, projecting future change, and the broader environmental and economic benefits to safeguard blue carbon ecosystems through law.
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Solan M, Archambault P, Renaud PE, März C. The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2020; 378:20200266. [PMID: 32862816 PMCID: PMC7481657 DOI: 10.1098/rsta.2020.0266] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Affiliation(s)
- Martin Solan
- School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK
- e-mail:
| | - Philippe Archambault
- ArcticNet, Québec Océan, Takuvik, Département de biologie, Université Laval, Québec, Canada
| | - Paul E. Renaud
- Akvaplan-niva, Fram Center for Climate and the Environment, 9296 Tromsø, Norway
- University Centre in Svalbard, Arctic Biology, 9171 Longyearbyen, Norway
| | - Christian März
- School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK
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Solan M, Ward ER, Wood CL, Reed AJ, Grange LJ, Godbold JA. Climate-driven benthic invertebrate activity and biogeochemical functioning across the Barents Sea polar front. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2020; 378:20190365. [PMID: 32862817 PMCID: PMC7481672 DOI: 10.1098/rsta.2019.0365] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Arctic marine ecosystems are undergoing rapid correction in response to multiple expressions of climate change, but the consequences of altered biodiversity for the sequestration, transformation and storage of nutrients are poorly constrained. Here, we determine the bioturbation activity of sediment-dwelling invertebrate communities over two consecutive summers that contrasted in sea-ice extent along a transect intersecting the polar front. We find a clear separation in community composition at the polar front that marks a transition in the type and amount of bioturbation activity, and associated nutrient concentrations, sufficient to distinguish a southern high from a northern low. While patterns in community structure reflect proximity to arctic versus boreal conditions, our observations strongly suggest that faunal activity is moderated by seasonal variations in sea ice extent that influence food supply to the benthos. Our observations help visualize how a climate-driven reorganization of the Barents Sea benthic ecosystem may be expressed, and emphasize the rapidity with which an entire region could experience a functional transformation. As strong benthic-pelagic coupling is typical across most parts of the Arctic shelf, the response of these ecosystems to a changing climate will have important ramifications for ecosystem functioning and the trophic structure of the entire food web. This article is part of the theme issue 'The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning'.
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Affiliation(s)
- Martin Solan
- School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK
- e-mail:
| | - Ellie R. Ward
- School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK
| | - Christina L. Wood
- School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK
| | - Adam J. Reed
- School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK
| | - Laura J. Grange
- School of Ocean Sciences, Bangor University, Bangor, Gwynedd LL57 2DG, UK
| | - Jasmin A. Godbold
- School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK
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