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Predators help protect carbon stocks in blue carbon ecosystems

Nature Climate Change volume 5, pages 10381045 (2015) | Download Citation

Abstract

Predators continue to be harvested unsustainably throughout most of the Earth's ecosystems. Recent research demonstrates that the functional loss of predators could have far-reaching consequences on carbon cycling and, by implication, our ability to ameliorate climate change impacts. Yet the influence of predators on carbon accumulation and preservation in vegetated coastal habitats (that is, salt marshes, seagrass meadows and mangroves) is poorly understood, despite these being some of the Earth's most vulnerable and carbon-rich ecosystems. Here we discuss potential pathways by which trophic downgrading affects carbon capture, accumulation and preservation in vegetated coastal habitats. We identify an urgent need for further research on the influence of predators on carbon cycling in vegetated coastal habitats, and ultimately the role that these systems play in climate change mitigation. There is, however, sufficient evidence to suggest that intact predator populations are critical to maintaining or growing reserves of 'blue carbon' (carbon stored in coastal or marine ecosystems), and policy and management need to be improved to reflect these realities.

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Acknowledgements

This work was supported by a working group grant from the Centre for Integrative Ecology at Deakin University, the Climate Change Consortium for Wales (C3W), CSIRO Marine and Coastal Carbon Biogeochemistry Cluster, and an Australian Research Council DECRA Grant awarded to P.I.M. (DE130101084). This is contribution no. 735 from the Southeast Environmental Research Center at Florida International University. We thank E. Hammill and R. Tackett for assistance with figures.

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Affiliations

  1. Global Change Institute, University of Queensland, St Lucia, Queensland 4072, Australia

    • Trisha B. Atwood
    •  & Catherine E. Lovelock
  2. Department of Watershed Sciences and Ecology Center, Utah State University, Logan, Utah 84322-5210, USA

    • Trisha B. Atwood
  3. Australian Rivers Institute – Coast & Estuaries, and School of Environment, Griffith University, Gold Coast, Queensland 4222, Australia

    • Rod M. Connolly
  4. Centre for Integrative Ecology, School of Life and Environmental Sciences, Faculty of Science Engineering and Built Environment, Deakin University, Victoria 3125, Australia

    • Euan G. Ritchie
    • , Graeme C. Hays
    •  & Peter I. Macreadie
  5. School of Biological Sciences, University of Queensland, St Lucia, Queensland 4072, Australia

    • Catherine E. Lovelock
  6. Department of Biological Sciences, Florida International University, Miami, Florida 33174, USA

    • Michael R. Heithaus
    •  & James W. Fourqurean
  7. Department of Biosciences, Swansea University, Singleton Park, Swansea, SA2 8PP, UK

    • Graeme C. Hays
  8. School of Plant Biology, University of Western Australia, Perth, Western Australia 6009, Australia

    • James W. Fourqurean
  9. Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, New South Wales 2007, Australia

    • Peter I. Macreadie

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Contributions

All authors helped to conceive the manuscript. T.B.A. led the writing with contributions from all authors. T.B.A., R.C., C.L. and J.F. contributed to data analyses.

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The authors declare no competing financial interests.

Corresponding author

Correspondence to Trisha B. Atwood.

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https://doi.org/10.1038/nclimate2763

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