Global distribution, formation and fate of mineral‐associated soil organic matter under a changing climate: A trait‐based perspective

Functional Ecology, Journal Year: 2022, Volume and Issue: 36(6), P. 1411 - 1429

Published: March 7, 2022

Abstract Soil organic matter (SOM) is the largest actively cycling reservoir of terrestrial carbon (C), and majority SOM in Earth's mineral soils (~65%) mineral‐associated (MAOM). Thus, formation fate MAOM can exert substantial influence on global C cycle. To predict future changes to climate, it critical mechanistically understand processes by which formed decomposed, accurately represent this process‐based understanding biogeochemical Earth system models. In review, we use a trait‐based framework synthesize interacting roles plants, soil micro‐organisms, matrix regulating decomposition. Our proposed differentiates between plant microbial traits that total OM inputs (‘feedstock traits’) versus proportion are ultimately incorporated into (‘MAOM traits’). We discuss how these feedstock may be altered warming, precipitation elevated dioxide. At planetary scale, help shape distribution across biomes, modulate biome‐specific responses climate change. leverage synthesis measurements provide estimates amount MAOM‐C globally (~840–1540 Pg C; 34%–51% C), its biomes. show concentration highest temperate forests grasslands, lowest shrublands savannas. Grasslands croplands have (SOC) fraction (i.e. MAOM‐C:SOC ratio), while boreal tundra ratio. Drawing our trait framework, then review experimental data posit effects change pools different conclude discussing integrated models, included also summarize projected under scenarios (Representative Concentration Pathways 4.5 8.5) key model uncertainties. Read free Plain Language Summary for article Journal blog.

Language: Английский

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The role of plant input physical-chemical properties, and microbial and soil chemical diversity on the formation of particulate and mineral-associated organic matter

Soil Biology and Biochemistry, Journal Year: 2022, Volume and Issue: 168, P. 108648 - 108648

Published: March 26, 2022

Language: Английский

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Where and why do particulate organic matter (POM) and mineral-associated organic matter (MAOM) differ among diverse soils?

Soil Biology and Biochemistry, Journal Year: 2022, Volume and Issue: 172, P. 108756 - 108756

Published: June 13, 2022

Language: Английский

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Nitrogen increases soil organic carbon accrual and alters its functionality

Global Change Biology, Journal Year: 2023, Volume and Issue: 29(7), P. 1971 - 1983

Published: Jan. 6, 2023

Abstract Nitrogen (N) availability has been considered as a critical factor for the cycling and storage of soil organic carbon (SOC), but effects N enrichment on SOC pool appear highly variable. Given complex nature pool, recent frameworks suggest that separating this into different functional components, example, particulate (POC) mineral‐associated (MAOC), is great importance understanding predicting dynamics. Importantly, little known about how these N‐induced changes in components (e.g., ratios among fractions) would affect functionality given differences nutrient density, resistance to disturbance, turnover time between POC MAOC pool. Here, we conducted global meta‐analysis 803 paired observations from 98 published studies assess effect addition fractions. We found addition, average, significantly increased pools by 16.4% 3.7%, respectively. In contrast, both were remarkably decreased (4.1% 10.1%, respectively). Increases positively correlated with aboveground plant biomass hydrolytic enzymes. However, positive responses increases microbial biomass. Our results although reactive deposition could facilitate C sequestration some extent, it might decrease time, disturbance study provides mechanistic insights its at scale, which pivotal dynamics especially future scenarios more frequent severe perturbations.

Language: Английский

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Cover crop functional types differentially alter the content and composition of soil organic carbon in particulate and mineral‐associated fractions

Global Change Biology, Journal Year: 2022, Volume and Issue: 28(19), P. 5831 - 5848

Published: June 17, 2022

Cover crops (CCs) can increase soil organic carbon (SOC) sequestration by providing additional OC residues, recruiting beneficial microbiota, and improving aggregation structure. The various CC species that belong to distinct plant functional types (PFTs) may differentially impact SOC formation stabilization. Biogeochemical theory suggests selection of PFTs with litter quality (C:N ratio) should influence the pathways magnitude sequestration. Yet, we lack knowledge on effect CCs from different quantity composition physiochemical pools SOC. We sampled soils under monocultures three (legume [crimson clover]; grass [triticale]; brassica [canola]) a mixture these species, long-term experiment in Pennsylvania, USA. measured C content bulk contrasting physical fractions: particulate matter, POM; mineral-associated MAOM. was higher all treatments compared fallow. Compared legume, lower (wider C:N) had proportion plant-derived POM, indicating selective preservation complex structural compounds. In contrast, legumes greater accumulation microbial-derived Our results for first time, revealed contributed concentration compounds POM relative MAOM brassica. Mixtures thus short- persistence balancing effects chemistries imposed monoculture PFTs. Thus, despite cumulative inputs PFTs, total stocks did not vary between rather impacted whether accumulated or fractions. This highlights shift dominant (POM vs. MAOM), subsequently impacting stabilization stocks. work provides strong applied field test biogeochemical linking accrual soil.

Language: Английский

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Moisture-driven divergence in mineral-associated soil carbon persistence

Proceedings of the National Academy of Sciences, Journal Year: 2023, Volume and Issue: 120(7)

Published: Feb. 6, 2023

Mineral stabilization of soil organic matter is an important regulator the global carbon (C) cycle. However, vulnerability mineral-stabilized (OM) to climate change currently unknown. We examined profiles from 34 sites across conterminous USA investigate how abundance and persistence mineral-associated C varied with at continental scale. Using a novel combination radiocarbon molecular composition measurements, we show that relationship between (MAOM) appears be driven by moisture availability. In wetter climates where precipitation exceeds evapotranspiration, excess leads deeper more prolonged periods wetness, creating conditions which favor greater root also allow for diffusion interaction inputs MAOM. these humid soils, concentration are strongly linked, whereas this absent in drier climates. arid lower, mineral surfaces limited shallower briefer moisture, resulting disconnect persistence. Data suggest tipping point cycling threshold equals evaporation. As patterns shift, our findings emphasize divergence mechanisms OM associated historical legacies need considered process-based models.

Language: Английский

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The Deep Soil Organic Carbon Response to Global Change

Annual Review of Ecology Evolution and Systematics, Journal Year: 2023, Volume and Issue: 54(1), P. 375 - 401

Published: Aug. 22, 2023

Over 70% of soil organic carbon (SOC) is stored at a depth greater than 20 cm belowground. A portion this deep SOC actively cycles on annual to decadal timescales and sensitive global change. However, responses change likely differ from surface because biotic controls cycling become weaker as mineral predominate with depth. Here, we synthesize the current information drivers warming, shifting precipitation, elevated CO 2 , land use cover Most can only be hypothesized few studies measure soils, even fewer experiments manipulate soils. We call scientists incorporate soils into their manipulations, measurements, models so that response accounted for in projections nature-based climate solutions terrestrial feedbacks

Language: Английский

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Particulate organic carbon is more sensitive to nitrogen addition than mineral-associated organic carbon: A meta-analysis

Soil and Tillage Research, Journal Year: 2023, Volume and Issue: 232, P. 105770 - 105770

Published: May 20, 2023

Language: Английский

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Distinct, direct and climate‐mediated environmental controls on global particulate and mineral‐associated organic carbon storage

Global Change Biology, Journal Year: 2023, Volume and Issue: 30(1)

Published: Dec. 25, 2023

Abstract Identifying controls on soil organic carbon (SOC) storage, and where SOC is most vulnerable to loss, are essential managing soils for both climate change mitigation global food security. However, we currently lack a comprehensive understanding of the drivers especially with regards particulate (POC) mineral‐associated (MAOC). To better understand hierarchical POC MAOC, applied path analyses fractions, (i.e., mean annual temperature [MAT] precipitation minus potential evapotranspiration [MAP‐PET]), (C) input net primary production [NPP]), property data synthesized from 72 published studies, along generated National Ecological Observatory Network pits ( n = 901 total observations). assess utility investigating MAOC separately in storage controls, then compared these results another analysis predicting bulk storage. We found that negatively related MAT pH, while positively NPP MAP‐PET, but % sand. Our revealed similar trends explained less variation C than our analyses. Given pH impose constraints microbial decomposition, this indicates primarily controlled by loss processes. In contrast, strong relationships variables plant productivity constraints, moisture, mineral surface availability sorption indicate climate‐driven variations inputs soil, as well stabilization mechanisms. Altogether, demonstrate separate environmental variables, further justifying need quantify model fractions forecast responses change.

Language: Английский

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Emergent temperature sensitivity of soil organic carbon driven by mineral associations

Nature Geoscience, Journal Year: 2024, Volume and Issue: 17(3), P. 205 - 212

Published: Feb. 20, 2024

Abstract Soil organic matter decomposition and its interactions with climate depend on whether the is associated soil minerals. However, data limitations have hindered global-scale analyses of mineral-associated particulate carbon pools their benchmarking in Earth system models used to estimate cycle–climate feedbacks. Here we analyse observationally derived global estimates quantify relative proportions compute climatological temperature sensitivities as decline increasing temperature. We find that sensitivity average 28% higher than carbon, up 53% cool climates. Moreover, distribution between these underlying drives emergent bulk stocks. vary widely predictions pool distributions. show proportion model are conceptually similar mineral-protected ranges from 16 85% across Coupled Model Intercomparison Project Phase 6 offline land models, implications for ages ecosystem responsiveness. To improve projections feedbacks, it imperative assess accurately predict vulnerability carbon.

Language: Английский

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