Conceptualizing soil organic matter into particulate and mineral‐associated forms to address global change in the 21st century

Global Change Biology, Journal Year: 2019, Volume and Issue: 26(1), P. 261 - 273

Published: Oct. 6, 2019

Managing soil organic matter (SOM) stocks to address global change challenges requires well-substantiated knowledge of SOM behavior that can be clearly communicated between scientists, management practitioners, and policy makers. However, is incredibly complex separation into multiple components with contrasting in order study predict its dynamics. Numerous diverse schemes are currently used, making cross-study comparisons difficult hindering broad-scale generalizations. Here, we recommend separating particulate (POM) mineral-associated (MAOM) forms, two fundamentally different terms their formation, persistence, functioning. We provide evidence highly physical chemical properties, mean residence times soil, responses land use change, plant litter inputs, warming, CO2 enrichment, N fertilization. Conceptualizing POM versus MAOM a feasible, well-supported, useful framework will allow scientists move beyond studies bulk SOM, but also consistent scheme across studies. Ultimately, propose the as best way forward understand dynamics context necessary recommendations managers

Language: Английский

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Digging deeper: A holistic perspective of factors affecting soil organic carbon sequestration in agroecosystems

Global Change Biology, Journal Year: 2018, Volume and Issue: 24(8), P. 3285 - 3301

Published: Jan. 17, 2018

Abstract The global magnitude (Pg) of soil organic carbon ( SOC ) is 677 to 0.3‐m, 993 0.5‐m, and 1,505 1‐m depth. Thus, ~55% lies below 0.3‐m Soils agroecosystems are depleted their stock have a low use efficiency inputs agronomic yield. This review collation synthesis articles published in peer‐reviewed journals. rates sequestration scaled up the level by linear extrapolation. Soil C sink capacity depends on depth, clay content mineralogy, plant available water holding capacity, nutrient reserves, landscape position, antecedent stock. Estimates historic depletion world soils, 115–154 (average 135) Pg equivalent technical potential or maximum need be improved. A positive budget created increasing input biomass‐C exceed losses erosion mineralization. hotspots sequestration, soils which farther from saturation, include eroded, degraded, desertified, soils. Ecosystems where feasible 4,900 Mha agricultural land including 332 equipped for irrigation, 400 urban lands, ~2,000 degraded lands. rate (Mg ha −1 year 0.25–1.0 croplands, 0.10–0.175 pastures, 0.5–1.0 permanent crops 0.3–0.7 salt‐affected chemically 0.2–0.5 physically prone erosion, 0.05–0.2 those susceptible wind erosion. Global 1.45–3.44 C/year (2.45 C/year).

Language: Английский

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Pathways of mineral‐associated soil organic matter formation: Integrating the role of plant carbon source, chemistry, and point of entry

Global Change Biology, Journal Year: 2018, Volume and Issue: 25(1), P. 12 - 24

Published: Oct. 19, 2018

To predict the behavior of terrestrial carbon cycle, it is critical to understand source, formation pathway, and chemical composition soil organic matter (SOM). There emerging consensus that slow-cycling SOM generally consists relatively low molecular weight substrates enter mineral as dissolved associate with surfaces (referred "mineral-associated OM," or MAOM). However, much debate contradictory evidence persist around: (a) whether C within MAOM pool primarily originate from aboveground vs. belowground plant sources (b) directly sorb undergo microbial transformation prior their incorporation into MAOM. Here, we attempt reconcile disparate views on by proposing a spatially explicit set processes link source pathway. Specifically, because distinct regions soil, propose fine-scale differences in abundance should determine probability substrate-microbe substrate-mineral interaction. Thus, areas high density (e.g., rhizosphere other hotspots) occur through an vivo turnover pathway favor are first biosynthesized carbon-use efficiency pool. In contrast, certain bulk soil), direct sorption intact partially oxidized compounds uncolonized surfaces, minimizing importance efficiency, favoring strong "sorptive affinity." Through this framework, thus describe how primacy biotic abiotic controls dynamics not mutually exclusive, but rather dictated. Such understanding may be integral more accurately modeling across different spatial scales.

Language: Английский

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The interplay between microbial communities and soil properties

Nature Reviews Microbiology, Journal Year: 2023, Volume and Issue: 22(4), P. 226 - 239

Published: Oct. 20, 2023

Language: Английский

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Iron-mediated organic matter decomposition in humid soils can counteract protection

Nature Communications, Journal Year: 2020, Volume and Issue: 11(1)

Published: May 7, 2020

Soil organic matter (SOM) is correlated with reactive iron (Fe) in humid soils, but Fe also promotes SOM decomposition when oxygen (O2) becomes limited. Here we quantify Fe-mediated OM protection vs. by adding 13C dissolved (DOM) and 57FeII to soil slurries incubated under static or fluctuating O2. We find uniformly protects only oxic conditions, DOM are added together: de novo FeIII phases suppress mineralization 35 47%, respectively. Conversely, alone increases 8% following oxidation 57FeIII. Under O2 limitation, 57FeIII preferentially reduced, increasing anaerobic of 74% 32‒41%, Periodic limitation common so does not intrinsically protect OM; rather require their own physiochemical contribute persistence.

Language: Английский

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Soil organic matter formation, persistence, and functioning: A synthesis of current understanding to inform its conservation and regeneration

Advances in agronomy, Journal Year: 2022, Volume and Issue: unknown, P. 1 - 66

Published: Jan. 1, 2022

Language: Английский

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Microbial spatial footprint as a driver of soil carbon stabilization

Nature Communications, Journal Year: 2019, Volume and Issue: 10(1)

Published: July 16, 2019

Abstract Increasing the potential of soil to store carbon (C) is an acknowledged and emphasized strategy for capturing atmospheric CO 2 . Well-recognized approaches C accretion include reducing disturbance, increasing plant biomass inputs, enhancing diversity. Yet experimental evidence often fails support anticipated gains, suggesting that our integrated understanding remains insufficient. Here we use a unique combination X-ray micro-tomography micro-scale enzyme mapping demonstrate first time plant-stimulated pore formation appears be major, hitherto unrecognized, determinant whether new inputs are stored or lost atmosphere. Unlike monocultures, diverse communities favor development 30–150 µm pores. Such pores micro-environments associated with higher activities, greater abundance such translates into spatial footprint microorganisms make on consequently storage capacity.

Language: Английский

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Soil Microbiomes Under Climate Change and Implications for Carbon Cycling

Annual Review of Environment and Resources, Journal Year: 2020, Volume and Issue: 45(1), P. 29 - 59

Published: June 2, 2020

Communities of soil microorganisms (soil microbiomes) play a major role in biogeochemical cycles and support plant growth. Here we focus primarily on the roles that microbiome plays cycling organic carbon impact climate change cycle. We first discuss current challenges understanding carried out by highly diverse heterogeneous microbiomes review existing knowledge gaps how will microbiome. Because stability is key metric to understand as changes, different aspects stability, including resistance, resilience, functional redundancy.We then recent research pertaining perturbations functions they carry out. Finally, new experimental methodologies modeling approaches under development should facilitate our complex nature better predict its future responses change.

Language: Английский

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Contrasting pathways of carbon sequestration in paddy and upland soils

Global Change Biology, Journal Year: 2021, Volume and Issue: 27(11), P. 2478 - 2490

Published: March 13, 2021

Paddy soils make up the largest anthropogenic wetlands on earth, and are characterized by a prominent potential for organic carbon (C) sequestration. By quantifying plant- microbial-derived C in across four climate zones, we identified that accrual is achieved via contrasting pathways paddy upland soils. Paddies 39%-127% more efficient soil (SOC) sequestration than their adjacent counterparts, with greater differences warmer cooler climates. Upland replenished C, whereas enriched proportion of plant-derived because retarded microbial decomposition under anaerobic conditions induced flooding paddies. Under both land-use types, maximal contribution plant residues to SOC at intermediate mean annual temperature (15-20°C), neutral (pH~7.3), low clay/sand ratio. contrast, high (~24°C), pH (~5), large ratio favorable strengthening necromass. The necromass waterlogged paddies climates likely due fast anabolism from bacteria, fungi unlikely be involved as they aerobic. In scenario conversion upland, total 504 Tg may lost CO

Language: Английский

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Global ecological predictors of the soil priming effect

Nature Communications, Journal Year: 2019, Volume and Issue: 10(1)

Published: Aug. 2, 2019

Identifying the global drivers of soil priming is essential to understanding C cycling in terrestrial ecosystems. We conducted a survey soils across 86 globally-distributed locations, spanning wide range climates, biotic communities, and conditions, evaluated apparent effect using 13C-glucose labeling. Here we show that magnitude positive (increase CO2 release through accelerated microbial biomass turnover) was negatively associated with SOC content respiration rates. Our statistical modeling suggests effects tend be negative more mesic sites higher contents. In contrast, single-input labile causes arid locations low results provide solid evidence plays critical role regulating effects, important implications for improvement models under change scenarios.

Language: Английский

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