Studies of the decomposition, transformation and stabilization of soil organic matter (SOM) have dramatically increased in recent years owing to growing interest in studying the global carbon (C) cycle as it pertains to climate change. While it is readily accepted that the magnitude of the organic C reservoir in soils depends upon microbial involvement, as soil C dynamics are ultimately the consequence of microbial growth and activity, it remains largely unknown how these microorganism-mediated processes lead to soil C stabilization. Here, we define two pathways—ex vivo modification and in vivo turnover—which jointly explain soil C dynamics driven by microbial catabolism and/or anabolism. Accordingly, we use the conceptual framework of the soil ‘microbial carbon pump’ (MCP) to demonstrate how microorganisms are an active player in soil C storage. The MCP couples microbial production of a set of organic compounds to their further stabilization, which we define as the entombing effect. This integration captures the cumulative long-term legacy of microbial assimilation on SOM formation, with mechanisms (whether via physical protection or a lack of activation energy due to chemical composition) that ultimately enable the entombment of microbial-derived C in soils. We propose a need for increased efforts and seek to inspire new studies that utilize the soil MCP as a conceptual guideline for improving mechanistic understandings of the contributions of soil C dynamics to the responses of the terrestrial C cycle under global change.
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References
Lal, R. Soil carbon sequestration impacts on global climate change and food security. Science 304, 1623–1627 (2004).
Trumbore, S. E. Potential responses of soil organic carbon to global environmental change. Proc. Natl Acad. Sci. USA 94, 8284–8291 (1997).
Eswaran, H., Van Den Berg, E. & Reich, P. Organic carbon in soils of the world. Soil Sci. Soc. Am. J. 57, 192–194 (1993).
Balser, T. C. in Encyclopedia of Soils in the Environment (ed. Hillel, D. ) 195–207 (Elsevier, 2005).
Stockmann, U. et al. The knowns, known unknowns and unknowns of sequestration of soil organic carbon. Agr. Ecosyst. Environ. 164, 80–99 (2013).
Davidson, E. A. & Janssens, I. A. Temperature sensitivity of soil carbon decomposition and feedbacks to climate change. Nature 440, 165–173 (2006).
Rustad, L. E., Huntington, T. G. & Boone, R. D. Controls on soil respiration: implications for climate change. Biogeochemistry 48, 1–6 (2000).
Liang, C. & Balser, T. C. Warming and nitrogen deposition lessen microbial residue contribution to soil carbon pool. Nat. Commun. 3, 1222 (2012).
Bardgett, R. D., Freeman, C. & Ostle, N. J. Microbial contributions to climate change through carbon cycle feedbacks. ISME J. 2, 805–814 (2008).
Schimel, J. & Schaeffer, S. M. Microbial control over carbon cycling in soil. Front. Microbiol. 3, 1–11 (2012).
Liang, C. & Balser, T. C. Microbial production of recalcitrant organic matter in global soils: implications for productivity and climate policy. Nat. Rev. Microbiol. 9, 75 (2011).
Cotrufo, M. F., Wallenstein, M. D., Boot, C. M., Denef, K. & Paul, E. The Microbial Efficiency-Matrix Stabilization (MEMS) framework integrates plant litter decomposition with soil organic matter stabilization: do labile plant inputs form stable soil organic matter? Glob. Change Biol. 19, 988–995 (2013).
Benner, R. Biosequestration of carbon by heterotrophic microorganisms. Nat. Rev. Microbiol. 9, 75–75 (2011).
Miltner, A., Bombach, P., Schmidt-Brücken, B. & Kästner, M. SOM genesis: microbial biomass as a significant source. Biogeochemistry 111, 41–55 (2012).
Schaeffer, A., Nannipieri, P., Kästner, M., Schmidt, B. & Botterweck, J. From humic substances to soil organic matter–microbial contributions. In honour of Konrad Haider and James P. Martin for their outstanding research contribution to soil science. J. Soils Sediments 15, 1865–1881 (2015).
Ludwig, M. et al. Microbial contribution to SOM quantity and quality in density fractions of temperate arable soils. Soil Biol. Biochem. 81, 311–322 (2015).
Kindler, R., Miltner, A., Richnow, H.-H. & Kastner, M. Fate of gram-negative bacterial biomass in soil—mineralization and contribution to SOM. Soil Biol. Biochem. 38, 2860–2870 (2006).
Schweigert, M., Herrmann, S., Miltner, A., Fester, T. & Kästner, M. Fate of ectomycorrhizal fungal biomass in a soil bioreactor system and its contribution to soil organic matter formation. Soil Biol. Biochem. 88, 120–127 (2015).
Liang, C., Cheng, G., Wixon, D. & Balser, T. An absorbing Markov chain approach to understanding the microbial role in soil carbon stabilization. Biogeochemistry 106, 303–309 (2011).
Jiao, N. et al. Microbial production of recalcitrant dissolved organic matter: Long-term carbon storage in the global ocean. Nat. Rev. Microbiol. 8, 593–599 (2010).
Kögel-Knabner, I. & Amelung, W. in Treatise on Geochemistry 2nd edn (eds. Holland, H. & Turekian, K. ) 157–215 (Elsevier, 2014).
Schmidt, M. W. I. et al. Persistence of soil organic matter as an ecosystem property. Nature 478, 49–56 (2011).
Hayes, M. H. B. & Swift, R. S. An appreciation of the contribution of Frank Stevenson to the advancement of studies of soil organic matter and humic substances. J. Soils Sediments http://dx.doi.org/10.1007/s11368-016-1636-6 (2017).
Lehmann, J. & Kleber, M. The contentious nature of soil organic matter. Nature 528, 60–68 (2015).
Lehmann, J. et al. Spatial complexity of soil organic matter forms at nanometre scales. Nat. Geosci. 1, 238–242 (2008).
Oades, J. M. The retention of organic matter in soils. Biogeochemistry 5, 35–70 (1988).
Hedges, J. I. & Oades, J. M. Comparative organic geochemistries of soils and marine sediments. Org. Geochem. 27, 319–361 (1997).
Sollins, P. et al. Sequential density fractionation across soils of contrasting mineralogy: evidence for both microbial- and mineral-controlled soil organic matter stabilization. Biogeochemistry 96, 209–231 (2009).
Grandy, A. S. & Neff, J. C. Molecular C dynamics downstream: the biochemical decomposition sequence and its impact on soil organic matter structure and function. Sci. Tot. Environ. 404, 297–307 (2008).
Hagerty, S. B. et al. Accelerated microbial turnover but constant growth efficiency with warming in soil. Nat. Clim. Change 4, 903–906 (2014).
Cornwell, W. K. et al. Plant species traits are the predominant control on litter decomposition rates within biomes worldwide. Ecol. Lett. 11, 1065–1071 (2008).
Waldrop, M. P. & Firestone, M. K. Microbial community utilization of recalcitrant and simple carbon compounds: Impact of oak-woodland plant communities. Oecologia 138, 275–284 (2004).
Strickland, M. S., Lauber, C., Fierer, N. & Bradford, M. A. Testing the functional significance of microbial community composition. Ecology 90, 441–451 (2009).
Poll, C., Ingwersen, J., Stemmer, M., Gerzabek, M. H. & Kandeler, E. Mechanisms of solute transport affect small-scale abundance and function of soil microorganisms in the detritusphere. Eur. J. Soil Sci. 57, 583–595 (2006).
Schimel, J., Balser, T. C. & Wallenstein, M. Microbial stress-response physiology and its implications for ecosystem function. Ecology 88, 1386–1394 (2007).
Strickland, M. S. & Rousk, J. Considering fungal:bacterial dominance in soils – methods, controls, and ecosystem implications. Soil Biol. Biochem. 42, 1385–1395 (2010).
Liang, C., Fujinuma, R., Wei, L. & Balser, T. C. Tree species-specific effects on soil microbial residues in an upper Michigan old-growth forest system. Forestry 80, 65–72 (2007).
Zhang, X. et al. Land-use effects on amino sugars in particle size fractions of an Argiudoll. Appl. Soil Ecol. 11, 271–275 (1999).
Nakas, J. P. & Klein, D. A. Decomposition of microbial cell components in a semi-arid grassland soil. Appl. Environ. Microbiol. 38, 454–460 (1979).
Six, J., Frey, S. D., Thiet, R. K. & Batten, K. M. Bacterial and fungal contributions to carbon sequestration in agroecosystems. Soil Sci. Soc. Am. J. 70, 555–569 (2006).
Wardle, D. A. A comparative assessment of factors which influence microbial biomass carbon and nitrogen levels in soil. Biol. Rev. 67, 321–358 (1992).
Dalal, R. C. Soil microbial biomass: what do the numbers really mean? Aust. J. Exp. Agr. 38, 649–665 (1998).
Xu, X., Thornton, P. E. & Post, W. M. A global analysis of soil microbial biomass carbon, nitrogen and phosphorus in terrestrial ecosystems. Glob. Ecol. Biogeogr. 22, 737–749 (2013).
Potthoff, M., Dyckmans, J., Flessa, H., Beese, F. & Joergensen, R. Decomposition of maize residues after manipulation of colonization and its contribution to the soil microbial biomass. Biol. Fertil. Soils 44, 891–895 (2008).
von Lützow, M. et al. Stabilization of organic matter in temperate soils: Mechanisms and their relevance under different soil conditions – a review. Eur. J. Soil Sci. 57, 426–445 (2006).
Sollins, P., Homann, P. & Caldwell, B. A. Stabilization and destabilization of soil organic matter: mechanisms and controls. Geoderma 74, 65–105 (1996).
Lehmann, J., Kinyangi, J. & Solomon, D. Organic matter stabilization in soil microaggregates: implications from spatial heterogeneity of organic carbon contents and carbon forms. Biogeochemistry 85, 45–57 (2007).
Wan, J., Tyliszczak, T. & Tokunaga, T. K. Organic carbon distribution, speciation, and elemental correlations within soil microaggregates: applications of STXM and NEXAFS spectroscopy. Geochim. Cosmochim. Acta 71, 5439–5449 (2007).
Solomon, D. et al. Micro- and nano-environments of carbon sequestration: multi-element STXM–NEXAFS spectromicroscopy assessment of microbial carbon and mineral associations. Chem. Geol. 329, 53–73 (2012).
Chen, C., Dynes, J. J., Wang, J., Karunakaran, C. & Sparks, D. L. Soft X-ray spectromicroscopy study of mineral-organic matter associations in pasture soil clay fractions. Environ. Sci. Technol. 48, 6678–6686 (2014).
Kallenbach, C. M., Frey, S. D. & Grandy, A. S. Direct evidence for microbial-derived soil organic matter formation and its ecophysiological controls. Nat. Commun. 7, 13630 (2016).
Lechtenfeld, O. J., Hertkorn, N., Shen, Y., Witt, M. & Benner, R. Marine sequestration of carbon in bacterial metabolites. Nat. Commun. 6, 6711 (2015).
Cui, L. et al. Impacts of vegetation type and climatic zone on neutral sugar distribution in natural forest soils. Geoderma 282, 139–146 (2016).
Zhu, B. & Cheng, W. Rhizosphere priming effect increases the temperature sensitivity of soil organic matter decomposition. Glob. Change Biol. 17, 2172–2183 (2011).
Nottingham, A. T., Griffiths, H., Chamberlain, P. M., Stott, A. W. & Tanner, E. V. J. Soil priming by sugar and leaf-litter substrates: a link to microbial groups. Appl. Soil. Ecol. 42, 183–190 (2009).
Fan, Z. & Liang, C. Significance of microbial asynchronous anabolism to soil carbon dynamics driven by litter inputs. Sci. Rep. 5, 9575 (2015).
Wallenstein, M. D. et al. Litter chemistry changes more rapidly when decomposed at home but converges during decomposition–transformation. Soil. Biol. Biochem. 57, 311–319 (2013).
Angers, D. A. & Mehuys, G. R. Barley and alfalfa cropping effects on carbohydrate contents of a clay soil and its size fractions. Soil. Biol. Biochem. 22, 285–288 (1990).
Quideau, S. A., Chadwick, O. A., Benesi, A., Graham, R. C. & Anderson, M. A. A direct link between forest vegetation type and soil organic matter composition. Geoderma 104, 41–60 (2001).
Stewart, C. E., Neff, J. C., Amatangelo, K. L. & Vitousek, P. M. Vegetation effects on soil organic matter chemistry of aggregate fractions in a Hawaiian forest. Ecosystems 14, 382–397 (2011).
Filley, T. R., Boutton, T. W., Liao, J. D., Jastrow, J. D. & Gamblin, D. E. Chemical changes to nonaggregated particulate soil organic matter following grassland-to-woodland transition in a subtropical savanna. J. Geophys. Res. Biogeosci. 113, 10269–10269 (2008).
Wickings, K., Grandy, A. S., Reed, S. C. & Cleveland, C. C. The origin of litter chemical complexity during decomposition. Ecol. Lett. 15, 1180–1188 (2012).
Acknowledgements
We would like to thank X. Zhang, T. Balser, J. Tiedje, E. DeLucia, J. Kao-Kniffin and M. Kästner for their help with the evolution of ideas and concepts, along with the career development of C.L. We would like to thank K. Wickings and H. Gan for valuable inputs during preparation of the manuscript, and J. Lehmann for constructive comments and suggestions to improve the manuscript at a later stage. Particularly, we would like to thank X. Zhu for enhancing the visual quality of the figures. This work was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDB15010303), the National Natural Science Foundation of China (No. 41471218), the National Key Research and Development Program of China (No. 2016YFA0600802), and the US Department of Energy, Office of Science, Office of Biological and Environmental Research. The grants or other support to C.L. from the National Thousand Young Talents Program of China and the Alexander von Humboldt Foundation of Germany are also acknowledged with gratitude.
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C.L. conceived the ideas, developed the conceptual framework, and drafted the original manuscript. C.L., J.P.S. and J.D.J. contributed to concept polishing and critical revision of the manuscript. All authors read and approved the final manuscript.
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Liang, C., Schimel, J. & Jastrow, J. The importance of anabolism in microbial control over soil carbon storage. Nat Microbiol 2, 17105 (2017). https://doi.org/10.1038/nmicrobiol.2017.105
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DOI: https://doi.org/10.1038/nmicrobiol.2017.105
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