Thermal adaptation of decomposer communities in warming soils
Top Cited Papers
Open Access
- 1 January 2013
- journal article
- review article
- Published by Frontiers Media SA in Frontiers in Microbiology
- Vol. 4, 333
- https://doi.org/10.3389/fmicb.2013.00333
Abstract
Temperature regulates the rate of biogeochemical cycles. One way it does so is through control of microbial metabolism. Warming effects on metabolism change with time as physiology adjusts to the new temperature. I here propose that such thermal adaptation is observed in soil microbial respiration and growth, as the result of universal evolutionary trade-offs between the structure and function of both enzymes and membranes. I review the basis for these trade-offs and show that they, like substrate depletion, are plausible mechanisms explaining soil respiration responses to warming. I argue that controversies over whether soil microbes adapt to warming stem from disregarding the evolutionary physiology of cellular metabolism, and confusion arising from the term thermal acclimation to represent phenomena at the organism- and ecosystem-levels with different underlying mechanisms. Measurable physiological adjustments of the soil microbial biomass reflect shifts from colder- to warmer-adapted taxa. Hypothesized declines in the growth efficiency of soil microbial biomass under warming are controversial given limited data and a weak theoretical basis. I suggest that energy spilling (aka waste metabolism) is a more plausible mechanism for efficiency declines than the commonly invoked increase in maintenance-energy demands. Energy spilling has many fitness benefits for microbes and its response to climate warming is uncertain. Modeled responses of soil carbon to warming are sensitive to microbial growth efficiency, but declines in efficiency mitigate warming-induced carbon losses in microbial models and exacerbate them in conventional models. Both modeling structures assume that microbes regulate soil carbon turnover, highlighting the need for a third structure where microbes are not regulators. I conclude that microbial physiology must be considered if we are to have confidence in projected feedbacks between soil carbon stocks, atmospheric CO2, and climate change.Keywords
This publication has 134 references indexed in Scilit:
- Measurement of soil bacterial colony temperatures and isolation of a high heat-producing bacteriumBMC Microbiology, 2013
- Prediction of Microbial Growth Rate versus Biomass Yield by a Metabolic Network with Kinetic ParametersPLoS Computational Biology, 2012
- Soil warming, carbon–nitrogen interactions, and forest carbon budgetsProceedings of the National Academy of Sciences of the United States of America, 2011
- On the ‘temperature sensitivity’ of soil respiration: Can we use the immeasurable to predict the unknown?Soil Biology and Biochemistry, 2010
- Warming alters the metabolic balance of ecosystemsPhilosophical Transactions B, 2010
- Global meta‐analysis of wood decomposition rates: a role for trait variation among tree species?Ecology Letters, 2008
- Resistance, resilience, and redundancy in microbial communitiesProceedings of the National Academy of Sciences of the United States of America, 2008
- Thermal acclimation and the dynamic response of plant respiration to temperatureTrends in Plant Science, 2003
- Acclimatization of soil respiration to warming in a tall grass prairieNature, 2001
- Responses of tree fine roots to temperatureNew Phytologist, 2000