Search

Globally, the increasing fire events in addition to climate change due to the emission of carbon dioxide (CO2) as well as other greenhouse gases exerts huge pressure on natural resources and their management. This phenomenon is more severe in the tropical region due to increasing population, urbanization, industrialization, existing pressures, and limiting conditions. In the present study, carbon (C) stock, carbon sequestration (Cseq), CO2 mitigation potential, C budget, and C flux of the seasonally dry forest ecosystem of Chhattisgarh under the influence of wildfire in the protected area and its proximity were evaluated. Four sites namely, high fire zone (HFZ), medium fire zone (MFZ), low fire zone (LFZ), and non‐fire zone (NFZ) were selected and marked based on fire return intervals (frequency) and extent of damage. The present work is a novel approach that assesses the impact of different fire frequencies on C dynamics of fire‐affected zones. The stratified sampling technique was used within a permanent plot of 1 hectare. Forest stands on each site were analyzed using 10 randomly placed quadrats (each 10 × 10 m in size) and data were collected from each site. Across the sites higher tree density was observed at NFZ and the lowest at HFZ.Total tree biomass ranged between 116.0 and 358.4 t ha−1 across the fire regimes. Total vegetation C stock ranged between 59.1 and 169.5 t ha−1 in different sites. The C mitigation and Cseq potential ranged between 186.2 and 575.3 t ha−1, and 7.1 and 15.9 t ha−1, respectively being highest in NFZ and lowest in HFZ. The species such as Anogeissus latifolia, Buchanania lanzan, Shorea robusta, Lannea coromandelica, Lagerstroemia parviflora, Ougeinia oojeinensis, Terminalia chebula, Terminalia tomentosa are the major contributor in biomass, C stock, C mitigation, and Cseq potential in different fire regimes. Thus, our findings would be highly useful in the restoration process of fire‐affected zones through the plantation of selective plant species. Therefore, the aforementioned species could be effectively utilized while going for an afforestation/reforestation program, and will be helpful in climate change adaptation and mitigation strategies under different fire zones. [ABSTRACT FROM AUTHOR]

Biomass estimation forms the foundation for tackling global climate issues across diverse land use systems (LUSs). A research initiative was undertaken to identify the maximum biomass allocation using an allometric approach, and to assess the carbon stock, CO2 sequestration, and carbon credit across diverse land use systems (LUSs) in the Vindhyan region of Mirzapur, Uttar Pradesh, India. This study aims to address climate change by identifying land‐use strategies that stabilize income and are easily adoptable by farmers. Tropical dry deciduous forest, agriculture, plantation, horticulture and agri‐horticulture LUSs were investigated using three combinations of custard apple (Annona squamosa), guava (Psidium guajava), bael (Aegle marmelos), mustard (Giriraj) (Brassica nigra), mustard (Pitambri) (Brassica juncea), and lentil (Lens culinaris) in an agri‐horticulture system. Seven treatments with varying carbon stocks were identified: tropical dry deciduous forest (T1) LUS (TDDFLUS); wheat based agriculture (T2) LUS (WBALUS); plantation based on teak (Tectona grandis) (T3) LUS (TBPLUS); horticulture based on karonda (Carissa carandas) (T4) LUS (KBHLUS); bael + lentil (Hul‐57) (T5) LUS (BLBLUS); guava + mustard (Giriraj) (T6) LUS (GMBLUS); and custard apple + mustard (Pitambri) (T7) LUS (CAMBLUS). The results indicate that the lowest and the highest bulk densities (ρb) were recorded in TDDFLUS and WBALUS at the depths of 0–20 cm and 20‐40 cm, respectively. The mean value of the soil organic carbon (SOC) stock ranged from 11.24–18.09 t ha−1. The average value of biomass, biomass carbon stock and biomass CO2 sequestration of seven treatments varied from 9.76–88.49 t ha−1, 4.88–44.25 t ha−1, and 17.91–162.39 t ha−1, respectively. The total carbon stock, CO2 sequestration, and carbon credit for the seven treatments varied from 16.57–64.64 t ha−1, 60.82–237.28 t ha−1 and 3040.821–11 863.89US$ ha−1, respectively. The results demonstrated that different LUSs have specific advantages and their application at farm level can encourage sustainability and increase biomass accumulation, leading to carbon sequestration. Agri‐horticulture‐based LUSs can lead to better livelihoods and can also offer numerous advantages such as increased yields of staple food crops and fruits, improved soil health, reduced soil erosion, and significant contributions to the mitigation of anthropogenic warming through CO2 sequestration. [ABSTRACT FROM AUTHOR]

Forestation is a key strategy for climate mitigation in China through its biogeochemical (BGC) effect of ecosystem carbon sequestration. Additionally, the BGC effect of forestation can be either reinforced or counteracted by concurrent biogeophysical processes (BGP effect) resulting in local land surface warming or cooling, which can be translated into CO2e (i.e., BGC effect) using a local transient climate response. Previous evaluations of the climate mitigation potential of future forestation in China have, however, focused on the BGC effect only and neglected the BGP effect, potentially leading to suboptimal forestation areas. Here, we determined priority forestation areas in China by incorporating both effects to maximize its global climate mitigation effect. Our results suggest an additional 167.2 Mha potentially suitable for forestation in China, exceeding the largest forestation target (86.8 Mha) possibly assumed by the government in 2060. The forestation‐induced BGP effect (18.7 ± 61.9 tCO2e ha−1) largely reinforces the BGC effect (458.2 ± 92.6 tCO2e ha−1) in China, yielding a total climate mitigation effect of 476.9 ± 114.2 tCO2e ha−1 over 40 years (2021–2060). Under the 2060 forestation target, considering both BGC and BGP effects will displace 17.7% (15.3 Mha) of the forestation area derived by considering the BGC effect alone. Integrating both BGC and BGP effects will lead to a CO2 uptake of 28.8 GtCO2e by 2060, 3.9 GtCO2e higher than the value obtained when considering the BGC effect only. Our results highlight the importance of considering BGP effect when making forestation policies for climate mitigation. Plain Language Summary: Forestation plays a crucial role in mitigating climate change through both carbon sequestration (biogeochemical or BGC effect) and modification of land surface temperature (biogeophysical or BGP effect). Maximizing forestation contribution to global climate mitigation requires maximizing the collective effects of both BGC and BGP through converting BGP to BGC, as temperature change is fundamentally driven by atmospheric CO2 changes which are further influenced by forestation BGC effect. However, previous evaluations of China's forestation potential almost completely focused on the BGC effect. This study identified optimal forestation areas to maximize their global climate mitigation effect in China by considering both BGC and BGP effects. Considering both effects will displace 17.7% (15.3 Mha) of forestation areas determined by considering only the BGC effect under the 2060 forestation target. Considering both effects also leads to a higher CO2 uptake of 3.9 GtCO2e than the value when considering the BGC effect only by 2060. Forestation‐induced BGC and BGP effects mostly work in synergy in China, mutually enhancing the overall climate benefits. Our findings have implications for future forestation policy in China to maximize its contribution to global climate mitigation. Key Points: The biogeophysical (BGP) effect should be included in the traditional forestation policies considering only biogeochemical (BGC) effectConsidering BGC and BGP effects will lead to 17.7% of forestation area being displaced, compared to considering the BGC effect only by 2060Integrating BGC and BGP effects exhibits a 15.8% (3.9 GtCO2e) increase in CO2 uptake by 2060 [ABSTRACT FROM AUTHOR]

Although afforestation is a potential strategy to mitigate climate change by sequestering carbon, its potential biophysical effects on climate, such as regulating surface albedo, evapotranspiration, and energy balance, have not been fully incorporated into climate change mitigation strategies. This is partly due to the challenges associated with modeling the complex bidirectional interactions between vegetation and climate. In this study, we assess the impact of afforestation on low cloud cover using a regional climate model (RCM) and Earth observation data, applying a space‐for‐time approach to overcome limitations that may arise from comparing satellite and RCM results, such as different background climate conditions or different extents of land cover change. Our results show a consistent increase in low cloud cover in Europe due to afforestation in both datasets (3.71% and 3.56% on average, respectively), but the magnitude and direction of this effect depend on various factors, including location, seasonality, and forest type. These results suggest that afforestation can have important feedbacks on the climate system, and that its biophysical effects must be considered in climate change mitigation strategies. Furthermore, we emphasize the role of the modeling community in developing accurate and reliable approaches to assess the biophysical effects of land cover change on climate. Plain Language Summary: Although forests can help combat climate change by capturing carbon dioxide, we haven't fully considered the potential impact they can have on the climate in terms of biophysical factors such as surface reflectivity, evaporation, and energy balance. This is because it's challenging to accurately model the complex interactions between forests and climate. In this study, we used a regional climate model and Earth observation data to examine how forests affect the amount of low‐lying clouds. We used a method that compares satellite and model data to overcome limitations arising from different climate conditions and changes in land cover. Our findings consistently show that forests increase the coverage of low clouds in Europe. However, the specific effects depend on factors such as the location, season, and forest type. These results indicate that forests can have significant impacts on the climate system, and it is important to consider these effects when developing climate change strategies. We also emphasize the need for accurate modeling to better understand how changes in forest cover influence the climate. Key Points: Forests increase the amount of low clouds in EuropeForests impact climate beyond carbon sequestration [ABSTRACT FROM AUTHOR]

Existing estimates of the climate mitigation potential from cropland carbon sequestration (C‐sequestration) are limited because they tend to assume constant rates of soil organic carbon change over all available cropland area, use relatively coarse land delineations, and often fail to adequately consider the agronomic and socioeconomic dimensions of agricultural land use. This results in an inflated estimate of the C‐sequestration potential. We address this gap by defining a more appropriate land base for cover cropping in the United States for C‐sequestration purposes: stable croplands in annual production systems that can integrate cover cropping without irrigation. Our baseline estimate of this suitable stable cropland area is 32% of current U.S. cropland extent. Even an alternative, less restrictive definition of stability results in a large reduction in area (44% of current U.S. croplands). Focusing cover crop implementation to this constrained land base would increase durability of associated C‐sequestration and limit soil carbon loss from land conversion to qualify for carbon‐specific incentives. Applying spatially‐variable C‐sequestration rates from the literature to our baseline area yields a technical potential of 19.4 Tg CO2e yr−1 annually, about one‐fifth of previous estimates. We also find the cost of realizing about half (10 Tg CO2e yr−1) of this potential could exceed 100 USD Mg CO2e−1, an order of magnitude higher than previously thought. While our economic analyses suggest that financial incentives are necessary for large‐scale adoption of cover cropping in the U.S., they also imply any C‐sequestration realized under such incentives is likely to be additional. Plain Language Summary: As a "Nature‐based Climate Solution" (NCS), the practice of cover cropping has received widespread attention and investment recently. Through cover cropping, croplands may be able to absorb and hold more carbon in soil, drawing down CO2 in the atmosphere (i.e., sequester carbon). However, the sequestration that is feasible, which reflects socioeconomic and land use considerations, remains unquantified. We estimate this feasible potential for carbon sequestration in the U.S. croplands from cover cropping and find it to be a fraction of previous estimates. A large portion of the reduction is due to our use of a more realistic and rigorous definition of the land area suitable for cover cropping for climate mitigation purposes. This land area comprises "croplands remaining croplands" (or stable croplands) that are planted to annual crops, like corn and soybeans, because they can more easily integrate the practice. We exclude irrigated croplands to conserve water resources. At just under 44 million ha, our baseline area estimate is 32% of the current U.S. cropland extent. The rest of the reduction is associated with our use of more conservative rates of increase in soil carbon from cover cropping than earlier studies that are more realistic for assessing soil carbon sequestration potential over large areas. Our economic analyses suggests that without financial incentives, implementing cover cropping could be expensive for most U.S. farmers. This high cost hurdle needs to be evaluated against the cost‐effectiveness of alternatives that compete for the same limited resources for climate mitigation. Key Points: For U.S. croplands, the feasible potential of carbon sequestration from cover cropping is a fraction of previous estimatesDefining the land base suitable for mitigation practices more realistically and rigorously is critical to estimating the feasible potentialCover cropping, though beneficial for soil health, may not be a low‐cost pathway for climate mitigation at scale in the U.S. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) sequestration in agricultural soils is an important tool for climate change mitigation within the EU soil strategy for 2030 and can be achieved via the adoption of soil management strategies (SMS). These strategies may induce synergistic effects by simultaneously reducing greenhouse gas (GHG) emissions and/or nitrogen (N) leaching. In contrast, other SMS may stimulate emissions of GHG such as nitrous oxide (N2O) or methane (CH4), offsetting the climate change mitigation gained via SOC sequestration. Despite the importance of understanding trade‐offs and synergies for selecting sustainable SMS for European agriculture, knowledge on these effects remains limited. This review synthesizes existing knowledge, identifies knowledge gaps and provides research recommendations on trade‐offs and synergies between SOC sequestration or SOC accrual, non‐CO2 GHG emissions and N leaching related to selected SMS. We investigated 87 peer‐reviewed articles that address SMS and categorized them under tillage management, cropping systems, water management and fertilization and organic matter (OM) inputs. SMS, such as conservation tillage, adapted crop rotations, adapted water management, OM inputs by cover crops (CC), organic amendments (OA) and biochar, contribute to increase SOC stocks and reduce N leaching. Adoption of leguminous CC or specific cropping systems and adapted water management tend to create trade‐offs by stimulating N2O emissions, while specific cropping systems or application of biochar can mitigate N2O emissions. The effect of crop residues on N2O emissions depends strongly on their C/N ratio. Organic agriculture and agroforestry clearly mitigate CH4 emissions but the impact of other SMS requires additional study. More experimental research is needed to study the impact of both the pedoclimatic conditions and the long‐term dynamics of trade‐offs and synergies. Researchers should simultaneously assess the impact of (multiple) agricultural SMS on SOC stocks, GHG emissions and N leaching. This review provides guidance to policymakers as well as a framework to design field experiments and model simulations, which can address knowledge gaps and non‐intentional effects of applying agricultural SMS meant to increase SOC sequestration. [ABSTRACT FROM AUTHOR]

There is a cross‐sectoral push among conservationists to simultaneously mitigate biodiversity loss and climate change, especially as the latter increasingly threatens the former. Growing evidence demonstrates that animals can have substantial impacts on carbon cycling. As such, there are increasing calls to use animal conservation and rewilding to dually overcome biodiversity loss and mitigate climate change.Specifically, trophic rewilding—which involves restoring intact animal communities, functional roles and trophic structure within food webs, and natural ecosystem processes—utilizes a rewilding framework to simultaneously support biodiversity conservation and carbon capture and storage. Trophic rewilding is a complex conservation approach to mitigating climate change, involving accurate estimations of baseline conditions and continuous monitoring of carbon cycling and species impacts within a system. It is also predicated on garnering social support for both the reintroduction and monitoring of a species, and obtaining the animals themselves.We are excited by the growing interest in this potential, but emphasize that a species' net impact on ecosystem carbon dynamics is context‐dependent. Caution is required whenever biodiversity conservation (including rewilding), climate change mitigation, and human welfare do not readily align. Hence—similar to other nature‐based solutions—these burgeoning efforts must avoid sweeping generalizations.To bolster successful trophic rewilding, we highlight a range of social and ecological context dependencies that can vary outcomes in a rewilded carbon cycle and provide ethical considerations for successful implementation.We conclude with an overview of the available technology to predict and monitor progress toward both biodiversity and climate mitigation goals. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The effects of releasing carbon from the terrestrial pool into the atmosphere have significant long‐term and short‐term implications that affect many parts of our globe. Agricultural fields might help to address these concerns and provide cost‐effective solutions, such as lowering carbon dioxide levels (CO2) in the atmosphere while raising carbon levels in the soil. In order to increase agricultural land's potential to absorb and store carbon, the proper selection of suitable microbial inoculants with the capability to sequester carbon into soils is critical. Soil quality and characteristics would improve as a result, and atmospheric carbon would therefore be reduced. Soil microbes have the potential to influence the level of organic matter, which has an impact on the soil's ecological system and characteristics. Soil microbes play a role in carbon sequestration in soils by regulating multiple and distinct pathways for CO2 inputs and losses, such as biochemical processes that could sequester CO2, the capacity to sediment carbonates, the rigid nature of their components and vegetative tissues, or the composition of complex substances that preserve carbon in the soil. Further research is needed to investigate if particular microbial strains that can sequester carbon will help enhance soil quality and prevent climate change. [ABSTRACT FROM AUTHOR]

Bioenergy with carbon capture and storage (BECCS) plays a vital role in most climate change mitigation scenarios, where a solution for sustainable near‐term bioenergy expansion is to grow energy crops such as perennial grasses on recently abandoned cropland. There is a need to combine model‐based insights into theoretical potential and future biomass supply with more fine‐grained sociotechnical analysis to move toward realistic policies and innovation strategies. We combine natural science insights anchored in quantitative bioenergy modeling with qualitative social science anchored in the multi‐level perspective. Using these mixed methods enables a global‐to‐local‐to‐global level assessment of near‐term bioenergy recultivation opportunities for abandoned cropland. Norway is the local case. There are three main findings. First, the ongoing recultivation trends for food/feed production risks making gains in aboveground carbon stocks from natural regrowth on the mapped abandoned cropland over a 30‐year evaluation period almost negligible. Second, delaying a BECCS recultivation of abandoned cropland will make it impossible to reach high‐end mitigation potentials, and an accelerated BECCS recultivation guided by a policy push is needed to ensure stronger mitigation. Third, we unravel several real‐world challenges associated with bioenergy resource and supply modeling. Remote‐sensing techniques alone cannot capture actual land availability for land‐based climate change mitigation strategies. Local‐level sociotechnical conditions are generally found insufficiently supportive to align with the rapid near‐term bioenergy crop expansion found in 2°C scenarios from integrated assessment. The integration of mixed quantitative and qualitative methods is key to better understand the role of BECCS in climate change mitigation. Plain Language Summary: Bioenergy with carbon capture and storage (BECCS) is a key option for mitigating climate change. The idea is to capture the carbon emitted when biomass is converted into fuels or burned for energy production and store it underground. One proposed solution to ramp‐up biomass supply involves growing energy crops, like perennial grasses, on recently abandoned farmland. To make realistic policies and strategies for the future, we need to connect the theoretical potential of BECCS with local context, considering social and technical factors. We combine two approaches: using numbers to model bioenergy and using social science to understand the human and political side. By using a mix of methods, we can assess the potential for a near‐term recultivation of abandoned cropland for bioenergy and BECCS. There were three main findings. First, the combined use of both natural science and social science methods can help us better understand the role of BECCS in climate change mitigation. Second, re‐using abandoned farmland for growing food or animal feed reduces the effectiveness of letting the land naturally recover for fighting climate change. Third a rapid BECCS recultivation of abandoned cropland increases achieved climate change mitigation relative to a delayed BECCS recultivation. Key Points: Mixed quantitative and qualitative methods are key to unravel the role of bioenergy and bioenergy with carbon capture and storage (BECCS) in climate change mitigationOngoing recultivation of abandoned cropland for food production limits aboveground carbon accumulation from natural regrowthPolicies to redirect recultivation toward BECCS are needed to maximize climate change mitigation [ABSTRACT FROM AUTHOR]

Mangroves are one of the most carbon‐dense forests on the Earth and have been highlighted as key ecosystems for climate change mitigation and adaptation. Hundreds of studies have investigated how mangroves fix, transform, store, and export carbon. Here, we review and synthesize the previously known and emerging carbon pathways in mangroves, including gains (woody biomass accumulation, deadwood accumulation, soil carbon sequestration, root and litterfall production), transformations (food web transfer through herbivory, decomposition), and losses (respiration as CO2 and CH4, litterfall export, particulate and dissolved carbon export). We then review the technologies available to measure carbon fluxes in mangroves, their potential, and their limitations. We also synthesize and compare mangrove net ecosystem productivity (NEP) with terrestrial forests. Finally, we update global estimates of carbon fluxes with the most current values of fluxes and global mangrove area. We found that the contributions of recently investigated fluxes, such as soil respiration as CH4, are minor (<1 Tg C year−1), while the contributions of deadwood accumulation, herbivory, and lateral export are significant (>35 Tg C year−1). Dissolved inorganic carbon exports are an order of magnitude higher than the other processes investigated and were highly variable, highlighting the need for further studies. Gross primary productivity (GPP) and ecosystem respiration (ER) per area of mangroves were within the same order of magnitude as terrestrial forests. However, ER/GPP was lower in mangroves, explaining their higher carbon sequestration. We estimate the global mean mangrove NEP of 109.1 Tg C year−1 (7.4 Mg C ha−1 year−1) or through a budget balance, accounting for lateral losses, a global mean of 66.6 Tg C year−1 (4.5 Mg C ha−1 year−1). Overall, mangroves are highly productive, and despite losses due to respiration and tidal exchange, they are significant carbon sinks. [ABSTRACT FROM AUTHOR]

Global concerns about climate change were once again expressed at the COP27 in Sharm El-Sheikh. Seaweed is frequently presented as a solution for climate mitigation. For a proper appraisal of its contribution to mitigating climate change, it is necessary to distinguish between, and critically scrutinize, the various pathways seaweed-based climate mitigations can take. This article identifies four different climate mitigation pathways and critically reflects on each. First, carbon sequestration, occurring when grown seaweed is left in the seas or, second, purposefully sunk. Third, carbon emission reduction, resulting when seaweed-based products replace products with a higher carbon footprint, either fossil based products or other organic material. Fourth, carbon emission avoidance, taking place when seaweed products are used to avoid greenhouse gas emissions in other production processes. Each of these pathways requires specific methods to quantify their magnitude and comes with critical questions to ask. The sequestration pathway requires monitoring of net carbon production and the amount of carbon that is eventually exported to the deep sea. Pathways 3 and 4 require Life Cycle Assessment and/or Carbon Footprint with system boundaries set to include the production system itself and installation thereof. We propose an unequivocal categorization in a belief that confusion on the benefits of seaweed will eventually impede development of seaweedbased solutions. [ABSTRACT FROM AUTHOR]

Forests play an essential role in climate change mitigation by absorbing carbon dioxide from the atmosphere and storing carbon in biomass. Carbon sequestration can be increased by the extension of rotation cycles in existing plantation forests. This study examines the cost‐effectiveness of the remuneration scheme employed by Verified Carbon Standard (VCS), a commonly used carbon accounting method based on the average amount of carbon stored in the forest. We compare the net present value of carbon remuneration under VCS with that of a scheme that remunerates actual carbon storage in each year which we call "current carbon accounting." We use data for an Acacia mangium plantation in Indonesia where the forestry sector is expected to contribute more than half of the reductions of carbon emissions according to Indonesia's Nationally Determined Contribution (NDC) under the Paris Agreement. For our baseline scenario, we find, first, that the payments needed to incentivise additional carbon storage under VCS are considerably higher than under current carbon accounting. Second, the inefficiency is more pronounced at lower discount rates. Third, recent prices reported for VCS forest credits are not sufficient to incentivise forest managers to lengthen the forest rotation in Indonesian plantation forests. Recommendations for Resource Managers: Older forests store more carbon. Using a multiple rotations model our study determines how carbon payments incentivise forest managers to lengthen the forest rotation and, hence, to sequester and store more carbon. Forest managers should consider carbon remuneration options in their forest management decisions, in particular when choosing the length of the rotation period.Optimal forest management is impacted by the design of the remuneration scheme. It matters in particular whether carbon sequestration or carbon storage is paid for.Fund managers can incentivise larger amounts of carbon storage through careful design of the carbon remuneration scheme. [ABSTRACT FROM AUTHOR]

Soils store large quantities of carbon in the subsoil (below 0.2 m depth) that is generally old and believed to be stabilized over centuries to millennia, which suggests that subsoil carbon sequestration (CS) can be used as a strategy for climate change mitigation. In this article, we review the main biophysical processes that contribute to carbon storage in subsoil and the main mathematical models used to represent these processes. Our guiding objective is to review whether a process understanding of soil carbon movement in the vertical profile can help us to assess carbon storage and persistence at timescales relevant for climate change mitigation. Bioturbation, liquid phase transport, belowground carbon inputs, mineral association, and microbial activity are the main processes contributing to the formation of soil carbon profiles, and these processes are represented in models using the diffusion–advection–reaction paradigm. Based on simulation examples and measurements from carbon and radiocarbon profiles across biomes, we found that advective and diffusive transport may only play a secondary role in the formation of soil carbon profiles. The difference between vertical root inputs and decomposition seems to play a primary role in determining the shape of carbon change with depth. Using the transit time of carbon to assess the timescales of carbon storage of new inputs, we show that only small quantities of new carbon inputs travel through the profile and can be stabilized for time horizons longer than 50 years, implying that activities that promote CS in the subsoil must take into consideration the very small quantities that can be stabilized in the long term. [ABSTRACT FROM AUTHOR]

The term carbon (C) sequestration has not just become a buzzword but is something of a siren's call to scientific communicators and media outlets. Carbon sequestration is the removal of C from the atmosphere and the storage, for example, in soil. It has the potential to partially compensate for anthropogenic greenhouse gas emissions and is, therefore, an important piece in the global climate change mitigation puzzle. However, the term C sequestration is often used misleadingly and, while likely unintentional, can lead to the perpetuation of biased conclusions and exaggerated expectations about its contribution to climate change mitigation efforts. Soils have considerable potential to take up C but many are also in a state of continuous loss. In such soils, measures to build up soil C may only lead to a reduction in C losses (C loss mitigation) rather than result in real C sequestration and negative emissions. In an examination of 100 recent peer‐reviewed papers on topics surrounding soil C, only 4% were found to have used the term C sequestration correctly. Furthermore, 13% of the papers equated C sequestration with C stocks. The review, further, revealed that measures leading to C sequestration will not always result in climate change mitigation when non‐CO2 greenhouse gases and leakage are taken into consideration. This paper highlights potential pitfalls when using the term C sequestration incorrectly and calls for accurate usage of this term going forward. Revised and new terms are suggested to distinguish clearly between C sequestration in soils, SOC loss mitigation, negative emissions, climate change mitigation, SOC storage, and SOC accrual to avoid miscommunication among scientists and stakeholder groups in future. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) sequestration is a key function of natural and semi-natural ecosystems. Restoring this property in terrestrial ecosystems has become central to the EU's climate change mitigation and adaptation strategies. However, SOC sequestration is a widely misunderstood concept. The different methodological approaches used to investigate and compare SOC stock under sustainable agricultural practices play a key role in reinforcing misconceptions about this complex process. This commentary paper aimed not only to provide a clear definition of SOC sequestration, but also to interpret the results that can be obtained for SOC stock change estimation using the SOC stock difference and the paired comparison methods, as well as to identify the soil carbon-related processes that achieve climate mitigation. SOC sequestration can be defined as the progressive increase in a site's SOC stock compared with pre-intervention via a net depletion and transfer of atmospheric CO2 into the soil, where it is retained as soil organic matter (SOM), by plants, plant residues, or other organic solids such as the material derived from the organic fraction of farming solid waste, which can be used as a fertilizer (e.g., manure, compost, biochar, and digestate), and that is produced or derived from that land unit. To date, the most appropriate way to determine whether a land unit's soil is a sink or rather a source of atmospheric CO2 is to implement the SOC stock difference method, provided the non-occurrence of carbon exchange between ecosystems. [ABSTRACT FROM AUTHOR]

The article discusses the importance of time in accurately defining and quantifying carbon sequestration in soils for climate change mitigation. The authors argue that the definition proposed by Don et al. is incomplete because it does not explicitly consider the time that carbon remains stored in an ecosystem. They emphasize that a comprehensive definition should include both the amount of carbon sequestered and the duration of its storage. The authors suggest that considering time in the definition of carbon sequestration is crucial for effective climate change actions. [Extracted from the article]

The article discusses the importance of soil carbon sequestration (SCS) as a tool to mitigate climate change. The authors estimate that agricultural soils have the potential to sequester 3-14 Gt CO2/year by 2050 through SCS practices. They emphasize that SCS should be implemented alongside emission reductions in all sectors. The article also highlights the need for better estimates of biomass availability for SCS practices and acknowledges the variability in carbon loss and saturation levels. The authors argue that undervaluing the potential of SCS can lead to inaction on climate change. [Extracted from the article]

The article "Climate change mitigation through soil carbon sequestration in working lands: A reality check" questions the validity and realism of claims made by Almaraz et al. regarding the potential magnitude of soil carbon sequestration (SCS) in agricultural soils. The authors argue that Almaraz et al. overestimate the availability of organic matter for compost and biochar, inaccurately interpret carbon sequestration rates, and make premature assumptions about the applicability of enhanced rock weathering. They emphasize the need for realistic evaluations of the limitations and trade-offs of SCS practices and caution against overly optimistic estimates that can mislead policymakers. The authors declare no conflicts of interest. [Extracted from the article]

Munoz et al. (2024) raised concerns regarding our recent contribution and the definition of the term C sequestration in soils (Don et al., 2024). We performed a review and therefore based our analysis on existing definitions of C sequestrations, mainly by the IPCC. We recommend sticking with terminologies around C sequestration and climate mitigation, as outlined in our review, in order to keep it consistent and manageable. [ABSTRACT FROM AUTHOR]