Microbial diversity drives carbon use efficiency in a model soil

Abstract

Empirical evidence for the response of soil carbon cycling to the combined effects of warming, drought and diversity loss is scarce. Microbial carbon use efficiency (CUE) plays a central role in regulating the flow of carbon through soil, yet how biotic and abiotic factors interact to drive it remains unclear. Here, we combine distinct community inocula (a biotic factor) with different temperature and moisture conditions (abiotic factors) to manipulate microbial diversity and community structure within a model soil. While community composition and diversity are the strongest predictors of CUE, abiotic factors modulated the relationship between diversity and CUE, with CUE being positively correlated with bacterial diversity only under high moisture. Altogether these results indicate that the diversity × ecosystem-function relationship can be impaired under non-favorable conditions in soils, and that to understand changes in soil C cycling we need to account for the multiple facets of global changes.

Warming rather than elevated CO2 shifts the rhizobacterial community composition in four maize‐growing soils

“…The reduction of microbial diversity may be associated with the warming-induced reduction in C-use efficiency of microbes due to the reducing activity of enzymes and increasing energy demands for protein turnover and membrane repair (Gruner et al, 2017;Sihi, Inglett, Gerber, & Inglett, 2017). Moreover, recent studies also indicated a positive relationship between soil microbial diversity and microbial C-use efficiency that could be hindered by increasing temperature (Domeignoz-Horta et al, 2020;Qiao et al, 2019).…”

Saving the planet with appropriate biotechnology: 1. Diagnosing the problems

“…We cannot rely on forests to mitigate the effects of climate change; they're dying because of it! Despite all these negative reports and seemingly pessimistic facts regarding trees, there remains some hope that better management of forests and their carbon stocks can help improve overall terrestrial carbon cycle management providing knowledge of the role of fungi and soil microbes in carbon cycling is implemented into sustainable forest management practices (Soudzilovskaia et al, 2019;Domeignoz-Horta et al, 2020).…”

Saving the Planet with Appropriate Biotechnology: 5. An Action Plan

“…We cannot rely on forests to mitigate the effects of climate change while they are dying because of it! Despite all these negatives there remains some hope that better management of forests and their carbon stocks can help improve overall terrestrial carbon cycle management providing knowledge of the role of fungi and soil microbes in carbon cycling is implemented into sustainable forest management practices (Soudzilovskaia et al, 2019;Domeignoz-Horta et al, 2020). There is more to terrestrial plant cover than just trees, of course, but the limitation that plants only store carbon while they are alive applies to all photosynthetic organisms (including aquatic ones); wherever the plant dies, its stored carbon is returned to the atmosphere through the respiration of the animals, fungi and bacteria that digest its biomass.…”