Emergent Properties of Microbial Activity in Heterogeneous Soil Microenvironments: Different Research Approaches Are Slowly Converging, Yet Major Challenges Remain

Frontiers in Microbiology, Journal Year: 2018, Volume and Issue: 9

Published: Aug. 27, 2018

Over the last 60 years, soil microbiologists have accumulated a wealth of experimental data showing that usual bulk, macroscopic parameters used to characterize soils (e.g., granulometry, pH, organic matter and biomass contents) provide insufficient information describe quantitatively activity microorganisms some its outcomes, like emission greenhouse gases. Clearly, new, more appropriate are needed, which reflect better spatial heterogeneity at microscale (i.e., pore scale). For long time, spectroscopic microscopic tools were lacking quantify processes scale, but major technological advances over 15 years made suitable equipment available researchers. In this context, objective present article is review progress achieved date in significant research program has ensued. This can be rationalized as sequence steps, namely quantification modeling physical-, (bio)chemical-, microbiological properties soils, integration these different perspectives into unified theory, upscaling and, eventually, development new approaches measure characteristics. At stage, been on physical front, lesser extent (bio)chemical one well, both terms experiments modeling. microbial aspects, whereas lot work devoted bacterial fungal appropriateness model assumptions cannot readily assessed because relevant extremely scarce. overall move forward, it will crucial make sure components systems does not keep lagging behind Concerning subsequent steps program, very little various disciplinary occurred so far, result, researchers yet able tackle scaling up level. Many challenges, them daunting, remain path ahead.

Language: Английский

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Environmental and microbial controls on microbial necromass recycling, an important precursor for soil carbon stabilization

Communications Earth & Environment, Journal Year: 2020, Volume and Issue: 1(1)

Published: Oct. 22, 2020

Abstract There is an emerging consensus that microbial necromass carbon the primary constituent of stable soil carbon, yet controls on stabilization process are unknown. Prior to stabilization, may be recycled by community. We propose efficiency this recycling a critical determinant rates. Here we explore in 27 UK grassland soils using isotope tracing and indicator species analysis. found was unaffected land management. Instead, increased with growth rate necromass, highest low historical precipitation. identified bacterial fungal indicators efficiency, which could used clarify mechanisms. conclude environmental have strong influence recycling, suggest this, turn, influences stabilization.

Language: Английский

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Reviews and syntheses: The mechanisms underlying carbon storage in soil

Biogeosciences, Journal Year: 2020, Volume and Issue: 17(21), P. 5223 - 5242

Published: Oct. 30, 2020

Abstract. Soil organic matter (OM) represents a key C pool for climate regulation but also an essential component soil functions and services. Scientific research in the 21st century has considerably improved our knowledge of its dynamics, particularly under pressure global disruption carbon cycle. This paper reviews processes that control dynamics soil, representation these over time, their dependence on variations major biotic abiotic factors. The most recent advanced gained includes following. (1) Most is composed small molecules, derived from living organisms, without transformation via additional polymerization; (2) microbial compounds are predominant long term; (3) primary belowground production contributes more to than aboveground inputs; (4) contribution less biodegradable low (5) two factors determine “yield” initial substrates: yield used by microorganisms association with minerals, poorly crystalline which stabilize compounds; (6) interactions between plants regulate turnover time therefore stocks; (7) among only few considered current modeling approaches (i.e., temperature, water content, pH, particle size, sometimes N interactions); (8) although models assume involved linear, there now many indications nonlinear linked OM (e.g., priming). Farming practices, therefore, affect stocks not through inputs effect organomineral interactions, yet it still been possible properly identify main mechanisms loss (or gain). Greater insight into interdependencies, hierarchy sensitivity agricultural practices could provide future levers action sequestration soil.

Language: Английский

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Rice paddy soils are a quantitatively important carbon store according to a global synthesis

Communications Earth & Environment, Journal Year: 2021, Volume and Issue: 2(1)

Published: Aug. 6, 2021

Abstract Rice paddies account for ~9% or the world’s cropland area and are characterized by environmental conditions promoting soil organic carbon storage, methane emissions to a lesser extent nitrous oxide emissions. Here, we synthesize data from 612 sites across 51 countries estimate global stocks in paddy soils determine main factors affecting storage. Paddy (0–100 cm) contain 18 Pg worldwide. decrease with increasing mean annual temperature pH, whereas precipitation clay content had minor impacts. Meta-analysis shows that can be increased through several management practices. However, greenhouse gas mitigation storage is generally outweighed increases Our results emphasize key role of cycle, importance minimizing anthropogenic

Language: Английский

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Tillage Changes Vertical Distribution of Soil Bacterial and Fungal Communities

Frontiers in Microbiology, Journal Year: 2018, Volume and Issue: 9

Published: April 9, 2018

Tillage can strongly affect the long-term productivity of an agricultural system by altering composition and spatial distribution nutrients microbial communities. The impact tillage methods on vertical soil communities is not well understood, correlation between distributions also clear. In present study, we investigated effects conventional (CT: moldboard ploughing), reduced (RT: rotary tillage), no (NT) bacterial fungal within profile (0–5 cm, 5–10 10–20 20–30 cm) using high-throughput sequencing 16S/ITS gene. Microbial differed properties sampling depth. treatment affected community structure depth, changed differently. Depth decay were significantly smaller in CT than RT NT, that greater NT. presence/absence species was main contributing factor for variation communities, whereas difference relative abundance species, suggesting niche-based process more important structuring distribution. Soil total carbon correlated with (especially anaerobic facaltatively groups) community. These results suggested different roles bacteria fungi sequestration crop residue shaping distribution, which might fertility.

Language: Английский

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Nutrient addition reduces carbon sequestration in a Tibetan grassland soil: Disentangling microbial and physical controls

Soil Biology and Biochemistry, Journal Year: 2020, Volume and Issue: 144, P. 107764 - 107764

Published: Feb. 25, 2020

Language: Английский

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Deconstructing the microbial necromass continuum to inform soil carbon sequestration

Functional Ecology, Journal Year: 2022, Volume and Issue: 36(6), P. 1396 - 1410

Published: Feb. 3, 2022

Abstract Microbial necromass is a large, dynamic and persistent component of soil organic carbon, the dominant terrestrial carbon pool. Quantification stocks its susceptibility to global change becoming standard practice in research. However, typical proxies used for do not reveal nature flows transformations within that ultimately determine persistence. In this review, we define deconstruct four stages continuum: production, recycling, stabilization destabilization. Current understanding dynamics described each continuum stage. We highlight recent advances, methodological limitations knowledge gaps which need be addressed pool sizes transformations. discuss controls on process rates aspects microscale structure including biofilms food web interactions. The relative importance stage then compared contrasting ecosystems climate drivers. From perspective continuum, draw three conclusions inform future First, persistence are more clearly defined when viewed through lens continuum; second, destabilization least understood with recycling also poorly evidenced outside few ecosystems; third, response unresolved most ecosystems. Future mechanistic research focused role biotic abiotic determining organo–mineral organo–organo interactions can different scenarios. Our review demonstrates deconstructing key predicting vulnerability changing world. Read free Plain Language Summary article Journal blog.

Language: Английский

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Soil redox dynamics under dynamic hydrologic regimes - A review

The Science of The Total Environment, Journal Year: 2020, Volume and Issue: 763, P. 143026 - 143026

Published: Oct. 20, 2020

Language: Английский

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Fire effects on the persistence of soil organic matter and long-term carbon storage

Nature Geoscience, Journal Year: 2021, Volume and Issue: 15(1), P. 5 - 13

Published: Dec. 23, 2021

Language: Английский

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Microbial Necromass in Soils—Linking Microbes to Soil Processes and Carbon Turnover

Frontiers in Environmental Science, Journal Year: 2021, Volume and Issue: 9

Published: Dec. 14, 2021

The organic matter of living plants is the precursor material stored in terrestrial soil ecosystems. Although a great deal knowledge exists on carbon turnover processes plant material, some (SOM) formation, particular from microbial necromass, are still not fully understood. Recent research showed that larger part original converted into biomass, while remaining modified by extracellular enzymes microbes. At end its life, biomass contributes to molecular imprint SOM as necromass with specific properties. Next appropriate environmental conditions, heterotrophic microorganisms require energy-containing substrates C, H, O, N, S, P, and many other elements for growth, which provided nutrients contained SOM. As easily degradable often scarce resources soil, we can hypothesize microbes optimize their energy use. Presumably, able mobilize building blocks (mono oligomers fatty acids, amino sugars, nucleotides) stoichiometry This contrast mobilizing only consuming new synthesis primary metabolites tricarboxylic acid cycle after complete degradation substrates. Microbial thus an important resource SOM, mining could be life strategy contributing priming effects providing growth cycles. Due needs microorganisms, conclude formation through depends flux. However, details variability use decay cycles yet understood linked fields science. Here, summarize current gain, use, decay, relevant processes, e. g. pump, C storage, stabilization. We highlight factors controlling contribution implications efficiency (CUE) identify process-based modelling understanding these various types under different climates.

Language: Английский

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