Grassland soil carbon sequestration: Current understanding, challenges, and solutions

Science, Journal Year: 2022, Volume and Issue: 377(6606), P. 603 - 608

Published: Aug. 4, 2022

Grasslands store approximately one third of the global terrestrial carbon stocks and can act as an important soil sink. Recent studies show that plant diversity increases organic (SOC) storage by elevating inputs to belowground biomass promoting microbial necromass contribution SOC storage. Climate change affects grassland modifying processes catabolism anabolism. Improved grazing management biodiversity restoration provide low-cost and/or high-carbon-gain options for natural climate solutions in grasslands. The achievable sequestration potential grasslands is 2.3 7.3 billion tons dioxide equivalents per year (CO2e year-1) restoration, 148 699 megatons CO2e year-1 improved management, 147 sown legumes pasturelands.

Language: Английский

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Microbial necromass as the source of soil organic carbon in global ecosystems

Soil Biology and Biochemistry, Journal Year: 2021, Volume and Issue: 162, P. 108422 - 108422

Published: Sept. 14, 2021

Language: Английский

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Global stocks and capacity of mineral-associated soil organic carbon

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: July 1, 2022

Abstract Soil is the largest terrestrial reservoir of organic carbon and central for climate change mitigation carbon-climate feedbacks. Chemical physical associations soil with minerals play a critical role in storage, but amount global capacity storage this form remain unquantified. Here, we produce spatially-resolved estimates mineral-associated stocks carbon-storage by analyzing 1144 globally-distributed profiles. We show that current total 899 Pg C to depth 1 m non-permafrost mineral soils. Although constitutes 66% 70% surface deeper layers, respectively, it only 42% 21% mineralogical capacity. Regions under agricultural management layers undersaturation carbon. Critically, degree indicates sequestration efficiency over years decades. that, across 103 carbon-accrual measurements spanning interventions globally, soils furthest from their are more effective at accruing carbon; rates average 3-times higher one tenth compared half Our findings provide insights into world’s soils, store carbon, priority regions actions management.

Language: Английский

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Soil carbon sequestration by root exudates

Trends in Plant Science, Journal Year: 2022, Volume and Issue: 27(8), P. 749 - 757

Published: May 20, 2022

Language: Английский

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Changes in plant inputs alter soil carbon and microbial communities in forest ecosystems

Global Change Biology, Journal Year: 2022, Volume and Issue: 28(10), P. 3426 - 3440

Published: Jan. 29, 2022

Global changes can alter plant inputs from both above- and belowground, which, thus, may differently affect soil carbon microbial communities. However, the general patterns of how input them in forests remain unclear. By conducting a meta-analysis 3193 observations 166 experiments worldwide, we found that alterations aboveground litter and/or root had profound effects on communities forest ecosystems. Litter addition stimulated organic (SOC) pools biomass, whereas removal litter, roots or (no inputs) decreased them. The increased SOC under suggested benefit sequestration despite accelerated decomposition. Unlike removal, no altered particulate carbon, all detrital treatments did not significantly change mineral-associated carbon. In addition, contrastingly community, with shifting it toward fungi, bacteria. Furthermore, responses biomass to positively correlated rate total input, suggesting quantity is critical controller belowground processes. Taken together, these findings provide insights into understanding productivity allocation affects cycling, functioning ecosystems global changes. Future studies take full advantage existing detritus should focus relative roles forming its fractions.

Language: Английский

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Clarifying the evidence for microbial‐ and plant‐derived soil organic matter, and the path toward a more quantitative understanding

Global Change Biology, Journal Year: 2022, Volume and Issue: 28(24), P. 7167 - 7185

Published: Aug. 31, 2022

Predicting and mitigating changes in soil carbon (C) stocks under global change requires a coherent understanding of the factors regulating organic matter (SOM) formation persistence, including knowledge direct sources SOM (plants vs. microbes). In recent years, conceptual models have emphasized primacy microbial-derived inputs, proposing that microbial physiological traits (e.g., growth efficiency) are dominant controls on quantity. However, quantitative studies challenged this view, suggesting plants make larger contributions to than is currently recognized by paradigm. review, we attempt reconcile these perspectives highlighting variation across estimates plant- versus may arise part from methodological limitations. We show all major methods used estimate plant substantial shortcomings, uncertainty our current estimates. demonstrate there significant overlap chemical signatures compounds produced microbes, roots, through extracellular decomposition litter, which introduces into use common biomarkers for parsing SOM, especially mineral-associated (MAOM) fraction. Although review contributed deeper limitations with constrain light advances, suggest now critical time re-evaluate long-standing methods, clearly define their limitations, develop strategic plan improving quantification SOM. From synthesis, outline key questions challenges future research mechanisms stabilization pathways.

Language: Английский

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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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Regenerative Agriculture—A Literature Review on the Practices and Mechanisms Used to Improve Soil Health

Sustainability, Journal Year: 2023, Volume and Issue: 15(3), P. 2338 - 2338

Published: Jan. 27, 2023

Conventional farming practices can lead to soil degradation and a decline in productivity. Regenerative agriculture (RA) is purported by advocates as solution these issues that focuses on health carbon sequestration. The fundamental principles of RA are keep the covered, minimise disturbance, preserve living roots year round, increase species diversity, integrate livestock, limit or eliminate use synthetic compounds (such herbicides fertilisers). overall objectives rejuvenate land provide environmental, economic, social benefits wider community. Despite RA, vast majority growers reluctant adopt due lack empirical evidence claimed profitability. We examined reported mechanisms associated with against available scientific data. literature suggests agricultural such minimum tillage, residue retention, cover cropping improve carbon, crop yield, certain climatic zones types. Excessive chemicals biodiversity loss ecosystem degradation. Combining livestock agroforestry same landscape several co-benefits. However, vary among different agroecosystems may not necessarily be applicable across multiple agroecological regions. Our recommendation implement rigorous long-term system trials compare conventional order build knowledge regional scales. This will policy-makers an base from which make informed decisions about adopting realise their economic achieve resilience climate change.

Language: Английский

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Beyond bulk: Density fractions explain heterogeneity in global soil carbon abundance and persistence

Global Change Biology, Journal Year: 2021, Volume and Issue: 28(3), P. 1178 - 1196

Published: Dec. 4, 2021

Understanding the controls on amount and persistence of soil organic carbon (C) is essential for predicting its sensitivity to global change. The response may depend whether C unprotected, isolated within aggregates, or protected from decomposition by mineral associations. Here, we present a synthesis relative influence environmental factors partitioning among pools, abundance in each pool (mg g-1 soil), (as approximated radiocarbon abundance) relatively unprotected particulate mineral-bound pools. We show that mineral-associated pools consistently differed one another degree relationship factors. Soil depth was best predictor persistence, though it accounted more variance persistence. Persistence all decreased with increasing mean annual temperature (MAT) throughout profile, whereas increased wetness index (MAP/PET) subsurface soils (30-176 cm). soil) climate varied depth. Mineral-associated surface (<30 cm) strongly than free C, but both showed attenuated responses at Overall, these relationships suggest strong properties, potential loss areas decreasing wetness. Relative significantly land cover types parent material lithologies. This variability pool's suggests not equally vulnerable Therefore, projections future based patterns bulk be misleading.

Language: Английский

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The role of large wild animals in climate change mitigation and adaptation

Current Biology, Journal Year: 2022, Volume and Issue: 32(4), P. R181 - R196

Published: Feb. 1, 2022

Language: Английский

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