Review Article | Published:

Microorganisms and climate change: terrestrial feedbacks and mitigation options

Nature Reviews Microbiology volume 8, pages 779790 (2010) | Download Citation

Abstract

Microbial processes have a central role in the global fluxes of the key biogenic greenhouse gases (carbon dioxide, methane and nitrous oxide) and are likely to respond rapidly to climate change. Whether changes in microbial processes lead to a net positive or negative feedback for greenhouse gas emissions is unclear. To improve the prediction of climate models, it is important to understand the mechanisms by which microorganisms regulate terrestrial greenhouse gas flux. This involves consideration of the complex interactions that occur between microorganisms and other biotic and abiotic factors. The potential to mitigate climate change by reducing greenhouse gas emissions through managing terrestrial microbial processes is a tantalizing prospect for the future.

Key points

  • Microorganisms are the most diverse and dominant organisms on the planet and are vital for ecosystem functioning. However, most of them cannot yet be cultured in the laboratory.

  • Microbial processes have a central role in the global fluxes of the key greenhouse gases carbon dioxide, methane and nitrous oxide, and these processes are likely to respond rapidly to climate change.

  • An improved mechanistic understanding of microbial controls of terrestrial greenhouse gas fluxes is essential to improve the prediction of climate models.

  • New and emerging molecular tools are now available to quantify the diversity of uncultivable microorganisms and their metabolic processes, which will help to improve our manipulation of their feedback responses to climate change.

  • There is huge potential to manage and manipulate microbial processes to mitigate climate change by reducing greenhouse gas emissions from terrestrial ecosystems.

  • To achieve this, an interdisciplinary approach is required that includes microbial ecology, environmental genomics, soil and plant science, and ecosystem modelling.

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Acknowledgements

The authors thank C. Campbell, G. Grelet and C. Macdonald for detailed discussions and comments on the manuscript. P.S. holds a Royal Society Wolfson Research Merit Award.

Author information

Affiliations

  1. Macaulay Land Use Research Institute, Aberdeen AB15 8QH, UK.

    • Brajesh K. Singh
  2. Centre for Plants and the Environment, University of Western Sydney, Penrith South, DCNSW 1797, Australia.

    • Brajesh K. Singh
  3. Institute of Biological and Environmental Sciences, Cruickshank Building, St Machar Drive, Aberdeen AB24 3UU, UK.

    • Brajesh K. Singh
    •  & Pete Smith
  4. Soil and Ecosystem Ecology Laboratory, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK.

    • Richard D. Bardgett
  5. School of GeoSciences, University of Edinburgh, Edinburgh EH9 3JW, UK.

    • Dave S. Reay

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Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Brajesh K. Singh.

Glossary

Radiative forcing

A measure of the influence that a factor has in altering the balance of incoming and outgoing energy in the Earth–atmosphere system. It is an index of the importance of the factor as a potential climate change mechanism.

Heterotrophic

Of an organism: able to use organic compounds as nutrients to produce energy for growth.

Autotrophic

Of an organism: able to synthesize organic carbon from the fixation of inorganic carbon (for example, by photosynthesis or chemosynthesis).

Dissolved inorganic carbon pool

The sum of inorganic carbon in solution.

Net primary production

The part of the total energy fixed by autotrophic organisms that remains after the losses through autotrophic respiration.

Methanogenesis

The process by which methane is produced by microorganisms (mainly archaea).

Methanotrophic

Of an organism: able to use methane as a nutrient to produce energy for growth.

Nitrification

The conversion of NH3 into a more oxidized form such as nitrate or nitrite.

Denitrification

The reduction of oxidized forms of nitrogen to N2O and dinitrogen.

Reactive nitrogen

Nitrogen in a form that can undergo biological transformations, such as nitrite and nitrate.

Permafrost

Soil that remains permanently frozen.

Recalcitrant carbon

A form of carbon that is resistant to microbial decomposition owing to its chemical structure and composition.

Peatland

An area dominated by deep organic soils.

Water table

The level at which the groundwater pressure is the same as the atmospheric pressure.

Arable land

Land that is used for growing crops.

Mineralization

The conversion of organic carbon into inorganic forms, mainly CO2.

Grassland

Land that has grass as the dominant vegetation.

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