Decomposition and transformations along the continuum from litter to soil organic matter in forest soils

Forest Ecology and Management, Journal Year: 2021, Volume and Issue: 498, P. 119522 - 119522

Published: July 31, 2021

Until recently, the processes of litter decomposition and soil organic matter formation in forests have been studied isolation, which has hindered development a comprehensive understanding entire process. The last decade brought considerable progress this scientific endeavour response to challenge sequester atmospheric C forest soils. In paper we review key recent developments field describe our current collective transformation pathways ecosystems. Compelling evidence that most slow-cycling SOM microbially transformed forces us rethink standard technique measuring mass remaining litterbags during incubation indicate rates. Rather than indicating remains undecomposed, these measurements reflect net outcome two simultaneous processes: plant material accumulation microbial faunal products. Measurement both pools, rather just total is necessary understand processes. For example, apparent retarding effect available N on loss late-stage may actually result from promoting production biomass necromass, thereby increasing products decay. We recommend referring as ‘net remaining’ or ‘residue mass’ ‘litter mass’, acknowledge its changing composition proceeds. Decomposition with abundant detritivorous meso- macrofauna remain poorly understood consequence inability litterbag capture their influences (even differing mesh sizes). Long-term studies monitoring faecal subsequent transformations are urgently needed. Roots mycorrhizal fungal hyphae important sources SOM, including stable SOM. Fine roots (orders 1 2) decompose particularly slowly, do some hyphae, attributed cell-wall constituents such lignins, melanin glycoproteins. Convergence curves litters initially quickly slowly indicates leaf litter, root residues large labile contents can generate much recalcitrant litters. Transformation into follow many pathways, depending characteristics site. Key site properties influence biotic community present together determine pathway follows As such, occur along continuum between situations aboveground mainly humus accumulates surface, partially decomposed transferred mineral via bioturbation. Predicting likely should inform decisions how measure interpret particular

Language: Английский

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Carbon farming: Are soil carbon certificates a suitable tool for climate change mitigation?

Journal of Environmental Management, Journal Year: 2023, Volume and Issue: 330, P. 117142 - 117142

Published: Jan. 4, 2023

Increasing soil organic carbon (SOC) stocks in agricultural soils removes dioxide from the atmosphere and contributes towards achieving neutrality. For farmers, higher SOC levels have multiple benefits, including increased fertility resilience against drought-related yield losses. However, increasing requires management changes that are associated with costs. Private certificates could compensate for these In schemes, farmers register their fields commercial certificate providers who certify increases. Certificates then sold as voluntary emission offsets on market. this paper, we assess suitability of an instrument climate change mitigation. From a soils' perspective, address processes enrichment, potentials limits, options cost-effective measurement monitoring. farmers' likely to increase SOC, discuss synergies trade-offs economic, environmental social targets. governance requirements guarantee additionality permanence while preventing leakage effects. Furthermore, questions legitimacy accountability. While is cornerstone more sustainable cropping systems, private fall short expectations mitigation sequestration cannot be guaranteed. Governance challenges include lack long-term monitoring, problems ensure additionality, safeguard effects, accountability if stored re-emitted. We conclude soil-based unlikely deliver offset attributed them benefit uncertain. Additional research needed develop standards metrics better understand impact term, non-permanent removals peaks atmospheric greenhouse gas concentrations probability exceeding climatic tipping points.

Language: Английский

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Forensic carbon accounting: Assessing the role of seaweeds for carbon sequestration

Journal of Phycology, Journal Year: 2022, Volume and Issue: 58(3), P. 347 - 363

Published: March 14, 2022

Carbon sequestration is defined as the secure storage of carbon‐containing molecules for >100 years, and in context carbon dioxide removal climate mitigation, origin this CO 2 from atmosphere. On land, trees globally sequester substantial amounts woody biomass, an analogous role seaweeds ocean has been suggested. The purposeful expansion natural seaweed beds aquaculture systems, including into open (ocean afforestation), proposed a method increasing use trading offset schemes. However, to verify whether fixed by through photosynthesis leads extremely complex marine environment compared terrestrial because need jointly consider: comparatively rapid turnover tracing fate via particulate dissolved organic pathways dynamic coastal waters, key atmosphere–ocean exchange. We propose Forensic Accounting approach, which thorough analysis flows between atmosphere ocean, out would be undertaken, assessing magnitude robust attribution seaweeds.

Language: Английский

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Roadmap for achieving net-zero emissions in global food systems by 2050

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: Sept. 5, 2022

Abstract Food systems (FSs) emit ~ 20 GtCO 2 e/y (~ 35% of global greenhouse gas emissions). This level tends to raise given the expected increases in food demands, which may threaten climate targets. Through a rapid assessment, evaluating 60+ scenarios based on existing low-emission and carbon sequestration practices, we estimate that intensifying FSs could reduce its emissions from 21.4 − 2.0 address increasing demands without relying offsets (e.g., related afforestation reforestation programs). However, historical trends regional contexts, more diverse portfolio including diet shifts new-horizon technologies, will be needed increase feasibility achieving net-zero FSs. One likely pathway consists implementing practices shift production 30th-percentile least emission-intensive 45% reduction), sequester at 50% potential 5 e/y) adopt technologies 6 e/y). For successful transition happen, would, next decade (2020s), need implement cost-effective mitigation supported by improvements countries’ governance technical assistance, innovative financial mechanisms research focused making affordable following two decades (2030–2050). work provides options vision guide 2050.

Language: Английский

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Handling the impacts of climate change on soil biodiversity

The Science of The Total Environment, Journal Year: 2023, Volume and Issue: 869, P. 161671 - 161671

Published: Jan. 16, 2023

Language: Английский

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Arbuscular mycorrhiza convey significant plant carbon to a diverse hyphosphere microbial food web and mineral‐associated organic matter

New Phytologist, Journal Year: 2024, Volume and Issue: 242(4), P. 1661 - 1675

Published: Feb. 15, 2024

Arbuscular mycorrhizal fungi (AMF) transport substantial plant carbon (C) that serves as a substrate for soil organisms, precursor of organic matter (SOM), and driver microbial dynamics. Using two-chamber microcosms where an air gap isolated AMF from roots, we

Language: Английский

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Carbon sequestration potential, challenges, and strategies towards climate action in smallholder agricultural systems of South Asia

Crop and Environment, Journal Year: 2022, Volume and Issue: 1(1), P. 86 - 101

Published: March 1, 2022

South Asia is a global hotspot for climate change with enormous pressure on land and water resources feeding the burgeoning population. The agricultural production systems are highly vulnerable in region primarily dominated by small marginal farmers intensive farming practices that had favored loss of carbon (C) from soil. This review discusses potential soil crop management such as minimum/reduced/no-tillage, use organic manure, balanced integrated plant nutrient application, precision levelling, pest management, residue cropping system optimization to maintain C-equilibrium between atmosphere enhance C-sequestration long run. Results meta-analysis show 36% increase C stock top 0–15 cm layer this which amounts ∼18 Mg stocks ha−1. Improved across crops environment may reduce methane em0ission 12% resulting an 8% reduction warming (GWP), while non-submerged condition led 51% GWP rice. Conservation agriculture fertilization also reduced 11 14%, respectively. Although several innovative resilient technologies having significant have been developed, there urgent need their scaling accelerated adoption C-sequestration. Policies programs be devised incentivizing adopt more C-neutral or C-positive practices. national governments other agencies should work towards together initiatives "4 per 1000" Initiative Global Soil Partnership, regional public-private partnership credits Regenerative Agriculture Grow Indigo-CIMMYT-ICAR India, addition research policy changes. will vital success sequestration action Asia.

Language: Английский

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Influence of Organic and Mineral Fertilizers on Soil Organic Carbon and Crop Productivity under Different Tillage Systems: A Meta-Analysis

Agriculture, Journal Year: 2022, Volume and Issue: 12(4), P. 464 - 464

Published: March 25, 2022

The intensive use of mineral (M) fertilizers may cause harm the environment via leaching or greenhouse gas emissions, destroy soil fertility as a consequence loss organic matter, and, due to their high price, they are economically unviable for producers. It is widely accepted that (O) deal with pressing challenges facing modern agriculture, even if farmers need improve knowledge applying in fertilization programs. A meta-analysis approach has been adopted evaluate effects on carbon (SOC) and crop yield O fertilizers, applied alone combination (MO) under conventional (CT), reduced (RT), no-tillage (NT) regimes. analysis was performed different climatic conditions, properties, species, irrigation management. Organic have positive influence increasing SOC compared M (on average 12.9%), values were observed NT (20.6%). results highlighted flexible environment-specific systems when considering subjected tillage Similarly, MO application showed better response CT RT coarse soils fertilizer 13.4 12.7%, respectively), while medium-textured soils, yielded than (9.5 11.2 vs. 2.5%, respectively). Among legumes 15.2%), among other few differences detected Under irrigated systems, led higher productivity CT, especially treatments 9.2 3.4%, importance environmental agronomical factors how understanding could affect impact these conservation farming practices sustainability system specific region.

Language: Английский

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Current controversies on mechanisms controlling soil carbon storage: implications for interactions with practitioners and policy-makers. A review

Agronomy for Sustainable Development, Journal Year: 2023, Volume and Issue: 43(1)

Published: Feb. 1, 2023

Abstract There is currently an intense debate about the potential for additional organic carbon storage in soil, strategies by which it may be accomplished and what actual benefits might agriculture climate. Controversy forms essential part of scientific process, but on topic soil storage, confuse agricultural community general public delay actions to fight climate change. In attempt shed light this topic, originality article lies its intention provide a balanced description contradictory opinions examine how can support decision-making despite controversy. first part, we review reconcile conflicting views mechanisms controlling dynamics soil. We discuss divergent chemical recalcitrance, microbial or plant origin persistent matter, contribution particulate matter spatial energetic inaccessibility decomposers. second advantages limitations big data management modeling, are tools link latest theories with taken stakeholders. Finally, show analysis discussion controversies guide scientists supporting stakeholders design (i) appropriate trade-offs biomass use forestry (ii) climate-smart practices, keeping mind their still unresolved effects storage.

Language: Английский

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TAMM review: Continuous root forestry—Living roots sustain the belowground ecosystem and soil carbon in managed forests

Forest Ecology and Management, Journal Year: 2023, Volume and Issue: 532, P. 120848 - 120848

Published: Feb. 9, 2023

An estimated half of the carbon fixed by trees is transported belowground, a portion which exuded into soil where it fuels complex belowground food web. The biological transformation exudates microbial metabolites and necromass major source organic matter (SOM), including persistent mineral-associated (MAOM). Recent recognition fundamental importance these inputs from living roots for sustaining life replenishing SOM demands rethinking how we harvest forests. By severing lifeline roots, clearcut harvesting devastates much biodiversity in forests, prohibits principal pathway through C stocks are replenished. Retention retains influence within retention patches potentially throughout harvested area, but only if inter-tree distances 15 m or less. sustain support re-establishment function following forest may mitigate post-harvest losses. Sustaining ecosystem via an underappreciated benefit continuous-cover forestry.

Language: Английский

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