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There has been a growing recognition in recent years that Electrofuels (e-fuels), also known as renewable and sustainable fuels, which are produced from hydrogen and carbon dioxide as the primary feedstocks, have great potential to reduce carbon footprint and address climate change. In the present study, contrary to most previous studies in which the sources of feedstock's preparation were considered as block boxes, two stand-alone processes are taken into account and incorporated into the e-fuels production system. H 2 is obtained by a high-temperature electrolysis system having an overall efficiency nearly twice that of a low-temperature electrolysis system. CO 2 is captured from a power plant flue gas stream with a purity of 99.81%. Investigating heat integration potential in such an integrated plant is an up-to-date and interesting topic and has not yet been well explored. Therefore, a heat integration within the three individual processes is implemented to reduce energy consumption. The design of the process-to-process heat transfer section is carried out using pinch design rules. By integrating individual units, approximately 42% of the required cold utility, traditionally supplied by chilled water and refrigerants, is allocated to generate high and medium-pressure steams. Having used the high-temperature steam electrolysis for H 2 production, a process that requires less external electricity compared to low-temperature water electrolysis, a power-to-liquid efficiency of 70% is achieved. Furthermore, the results reveal a carbon conversion ratio of 98.6%, indicating the effective converting the carbon from the feedstock into liquid hydrocarbons. [Display omitted] • Heat integration between e-fuels unit and its feedstocks supplier units is done. • Shell-and-tube and plate-fin exchangers are used to design heat exchanger network. • Required cold utilities in the processes decreases by 42% by steam generation. • Power-to-liquid efficiency is improved by 70% through the integration. • Effective converting carbon from the feedstock into liquid hydrocarbons by 98.62%. [ABSTRACT FROM AUTHOR]

• This study was conducted to estimate the carbon stocks of the Geramo forest. • The biomass of 73 woody species (trees and shrubs) was estimated using appropriate allometric equations. • The four forest carbon pools (AGB, BGB, LHG and SOC) were considered to determine carbon stock density in this study. • The estimated total carbon stock of the Geramo forest was about 57,994 Mg h−1. • The estimated climate change mitigation potential of the study forest was about 212,838.1 Mg h−1. Forests play a vital role in the global carbon balance and combating global climate change by sequestering and retaining carbon from the atmosphere in their biomass and soil. Thus, this study aims to estimate the carbon stocks in the biomass and soil along with various environmental factors in the Geramo forest in southern Ethiopia. Ninety-six plots (20 × 20 m2) were laid at a distance of 250 m along 16 line transects that were laid 300 m apart. Five 1 × 1 m2 subplots (4 at the corner and 1 at the center) were laid inside each main plot for LHG and soil data collection. The results revealed that the estimated total carbon stocks and mean carbon stock densities of the study forest were 57994 Mg h−1and 604 ± 344 Mg h−1, respectively, with a mean CO 2 equivalent of 2217 ± 1262 Mg h−1. This result indicates the remarkable role of the Geramo forest in carbon stock and sequestration potential compared with other remnant forests in Ethiopia. Thus, the Geramo forest plays a crucial role in climate change mitigation through carbon sequestration, and hence, this forest can generate carbon credits as financial benefits to the nearby population in the future. The results also revealed that anthropogenic disturbances were negatively associated with the carbon stocks of the forest. Therefore, sustainable forest conservation activities are needed to conserve forest resources, protect the forest from growing anthropogenic disturbances, and sustain its current global climate change mitigation and adaptation benefits. [ABSTRACT FROM AUTHOR]

To limit the effects of global warming, arid lands, which constitute approximately one-third of terrestrial surfaces and are not utilized for agriculture, could serve as an effective method for long-term carbon (C) storage. We propose that soil–plant–microbiome engineering with oxalogenic plants and oxalotrophic microbes could facilitate C sequestration on a global scale. [ABSTRACT FROM AUTHOR]

Carbon dioxide removal (CDR) technologies at a gigaton scale need to be developed and implemented within the next decades to keep global warming below 1.5 °C. Coastal enhanced silicate weathering is one of the proposed CDR techniques that aims to accelerate the natural process of CO 2 -sequestration during marine chemical weathering of silicate minerals. To this end, finely ground rock containing olivine (Mg x Fe 2− x SiO 4) could be dispersed in dynamic coastal environments, where local biotic and abiotic factors potentially enhance the weathering process. However, accurate predictions of the olivine dissolution rate and the associated CO 2 sequestration under in situ conditions are currently lacking and ecosystem impacts remain to be assessed. Previously, it has been hypothesized that in situ grain collisions, induced by bed load transport due to currents and waves, could accelerate the in situ chemical weathering of olivine particles. To examine this, we investigated the effects of continuous grain tumbling on olivine dissolution in natural seawater. A 70-day experiment was conducted in which forsterite olivine sand was continuously tumbled in filtered seawater at different rotation speeds, and dissolution rates were measured on a weekly basis. Results showed that continuously tumbled olivine dissolved 8 to 19 times faster compared to stagnant (no rotation) conditions. Olivine dissolution was complete and stoichiometric (except for Ni release), air-seawater CO 2 exchange was not significantly rate limiting, and minimal particle fragmentation and secondary mineral formation were observed. Hence, we infer that olivine weathering was mainly enhanced via advective pore water flushing, which limits saturation effects at the grain scale. Overall, this study provides evidence that ambient physical stresses in coastal environments could enhance marine silicate weathering, which has implications for both the natural silicon cycle as well as the use of enhanced coastal weathering of silicates as a CDR technique. [ABSTRACT FROM AUTHOR]

Forests are the largest pool of carbon in terrestrial ecosystems and are important for climate change mitigation. By analyzing the carbon sequestration process of forest ecosystem, the carbon sequestration amount of forest can be modeled as a nonlinear function, and the mechanism of forest carbon sequestration can be discussed on this basis. The research first introduced the relevant theories of forest carbon sequestration, followed by the preparation of the visualization system construction based on the research area and data sources, and then the construction of the visualization system, and finally carried out the simulation verification. The results show that the system is effective and accurate. [ABSTRACT FROM AUTHOR]

Agriculture contributes to global climate change by producing 20–25% of greenhouse gases (GHGs). CO 2 is released from deforestation and land conversion, methane from rice paddy fields, and nitrous oxides from overfertilization. An increasing world population requires a change in the agro food systems, including a reduction in chemical fertilizers and pesticides as well as the production and access to food. Greenhouse gas (GHG) emissions have created a global climate crisis which requires immediate interventions to mitigate the negative effects on all aspects of life on this planet. As current agriculture and land use contributes up to 25% of total GHG emissions, plant scientists take center stage in finding possible solutions for a transition to sustainable agriculture and land use. In this article, the PlantACT! (Plants for climate ACTion!) initiative of plant scientists lays out a road map of how and in which areas plant scientists can contribute to finding immediate, mid-term, and long-term solutions, and what changes are necessary to implement these solutions at the personal, institutional, and funding levels. [ABSTRACT FROM AUTHOR]

Mitigation pathways that stabilise global warming to 1.5 °C describe rapidly increasing deployment of land-based solutions, including increased carbon sequestration in soils and biomass. This places additional demands on land, which is also required to provide food security and other ecosystem services. Sustainable Intensification (SI) of agriculture has the potential to facilitate meeting demands for food and fibre, while simultaneously meeting environmental and ecological goals. The scientific literature has most often addressed the challenge of SI separately to climate change mitigation objectives in agricultural systems. Using a systematic review approach, we explored the compatibility of SI and carbon sequestration research through two contrasting case studies: Case Study I on Grassland Agriculture in Europe, and Case Study II on Smallholder Agriculture in Africa. We find contrasting levels of research theme similarity for SI and carbon sequestration, with European grassland agriculture research having lower similarity compared with African smallholder agriculture research. There was a focus on minimising biodiversity loss and environmental impacts in Europe, in contrast to a food security emphasis in Africa, reflecting regional and development differences. While there are clear context and agricultural-system specific differences between both case studies, both suggest that sustainable land use policies can be used to achieve SI integrated with climate mitigation in agriculture. • Climate mitigation pathways increasingly incorporate land-based carbon storage. • Sustainable intensification (SI) of agriculture may reduce demand for land. • We investigated the compatibility of research on SI and carbon sequestration. • There were significant contrasts reflecting a need for better integration. • Sustainable land use policies can help achieve mitigation where integrated with SI. [ABSTRACT FROM AUTHOR]

• Biogas upgrading is environmentally and energetically favourable over combustion. • Storage or utilisation of the captured CO 2 has larger savings than biogas upgrading. • Upgrading, CO 2 storage or utilisation perform well in all impact categories. • The energy system has a substantial impact on the environmental performance. • Methanation provides large climate change savings only in renewable energy systems. Biogas from anaerobic digestion is an important renewable energy source. Combining its utilisation with carbon capture and storage (CCS) or carbon capture and utilisation (CCU) may improve climate change performance. This study uses life cycle assessment to evaluate the environmental impacts of 17 biogas management technology configurations (TCs). The technologies include biogas combustion, upgrading to natural gas quality, CCS, direct utilisation of CO 2 and methanation. The focus is mainly on energy balances and climate change impacts, and the results are subjected to sensitivity-, uncertainty-, and energy system analysis. The TCs with CCS and CCU provide the largest climate change savings (-1400 to - 2100 kg CO 2 -eq/1000 Nm3 biogas). Specifically, the methanation TCs provide the highest savings, but they also depend strongly on the energy sources. When combustion and upgrading TCs are amended with CCS, the resulting climate change savings are robust across the energy systems. The biogas upgrading TCs exhibit substantial climate change savings, mainly due to the natural gas substitution. Combustion TCs without CCS have the lowest climate change savings and the highest quantified uncertainties. The biogas upgrading TCs with storage or direct utilisation of CO 2 provide a good compromise between climate change savings and energy recovery. In the remaining impact categories, the CCU TCs generally perform best, followed by the upgrading TCs and finally, the combustion TCs. The CCS TCs consistently perform worse than their counterparts without CCS, opposite to the climate change results. Overall, amending biogas utilisation with CCS or CCU can contribute to climate change mitigation. [ABSTRACT FROM AUTHOR]

Direct air capture (DAC) of CO 2 is considered one of the most promising carbon capture methods to reduce ambient CO 2 concentration for climate change mitigation. Biochar represents an attractive adsorbent for DAC because it is environmentally friendly and cost-effective. In this work, KOH-activated bamboo biochar shows the CO 2 capture capacity of 3.49 mmol g−1 (25 °C, 1 bar), and it is used as an adsorbent to perform direct air capture using a fixed-bed reactor with an ambient CO 2 capture capacity of up to 51.74 μmol g−1. Furthermore, the effect of relative humidity on CO 2 adsorption by biochar was investigated and exhibited promising stability under 2.7% relative humidity. However, the biochar activity for CO 2 capture is reduced to 63.88% under 67.1% humidity after 50 cycles. [Display omitted] • KOH was used to activate bamboo-derived biochar. • Bamboo biochar was investigated in direct air capture of CO 2. • Gas selectivity of biochar during direct air capture. • Effect of relative humidity on direct air capture efficiency. [ABSTRACT FROM AUTHOR]

This study evaluates the environmental impacts associated with the conversion of garden organic waste into value-added products, namely compost or biochar, employing various processes. Three distinct scenarios are considered: composting garden organic waste followed by screening of oversized materials (CBP), pyrolysis of oversized screenings of compost into biochar AP(I), and in-situ conversion of garden organics into biochar AP(II). A comprehensive Life Cycle Assessment (LCA) was conducted using OpenLCA software and life cycle impact assessment was conducted using Recipe 2016 midpoint methodology. The environmental ramifications of each scenario were assessed, optimising transport distances in AP(II) to achieve a functional unit of one tonne of biochar produced within a cradle-to-gate system boundary. For the first time, this study offers a holistic exploration of the benefits of soil biochar application, extending its scope to climate change mitigation, incorporating the optimisation of transport distance and its influence when scaling up the technology. The results revealed that global warming was increased from 125 kgCO 2 eq during composting of garden waste to 232 kgCO 2 eq where oversized screenings of compost is converted to biochar at an off-site facility. However, direct conversion of the oversized organic waste to biochar, without composting, showed reduced global warming impact of 56 kgCO 2 eq, and is thus the most favourable scenario to limit climate impacts of this fraction of organic garden waste. However, among 18 environmental impact indicators studied, eight indicators were either not influenced or did not significantly increase by transport distance to an off-site pyrolysis facility, while the magnitude of 10 impact indicators increased with transport distance. The insights and methodologies presented in this study hold global relevance, based on an actual case study in regional Australia, offering valuable recommendations for sustainable waste management practices and establishing biochar as a carbon-neutral or carbon-negative solution. The findings contribute to existing waste management knowledge and provide guidance for accessible carbon dioxide removal and soil carbon sequestration technologies. [Display omitted] • A comprehensive LCA for valorisation of garden organics was conducted. • Direct conversion of garden organics to biochar showed least potential environmental impacts. • Biochar provides opportunities for avoided, reduced, and removed carbon from atmosphere. • Maximum transport distance has been identified for individual impact categories. [ABSTRACT FROM AUTHOR]

• Novel CO 2 capture technology using three-phase gas-solid-liquid fluidization. • Process intensification of CO 2 capture through mass transfer enhancement. • Reduced capital cost for absorption unit by 40 % compared to packed bed systems. • Lower capital cost of CO 2 capture unit by 15 % compared to traditional technologies. • Reduced power production cost in a 1000 MW plant with integrated CO 2 capture. This study addresses the pressing need to mitigate anthropogenic carbon dioxide emissions from energy-intensive industrial sectors to achieve climate neutrality goals. The focus of this paper is on evaluating the industrial feasibility of a novel three-phase gas-solid-liquid fluidized bed absorption column using mono-ethanol-amine for carbon capture and comparing it with conventional packed-bed technology. The findings show that the fluidized bed configuration reduces capital costs of the absorber by 40 % and of the carbon capture unit by 15 % compared to the packed-bed technology, leading to decreased electricity costs when used as additional unit for a 1000 MW power plant. The proposed mathematical model incorporates key factors such as hydrodynamics, mass transfer, and chemical reactions, accurately describing the intensified carbon dioxide absorption process. This intensified system enhances the transferred carbon dioxide flowrate between phases, increasing overall decarbonization capacity while reducing capital and operational costs, offering a promising solution for industrial carbon capture. [ABSTRACT FROM AUTHOR]

Mangrove forests play a crucial role in the coastal environment. A plethora of research is focusing on mangroves' role in climate mitigation through sequestering and storing CO 2. This study aims to assess the organic carbon (OC) stocks and carbon sequestration rate (CSR) of the largest stands of mangroves in the Red Sea Coast of Egypt, to evaluate their significance in climate mitigation strategies. Intensive sampling was conducted in mangrove stands of Safaga, Qulaan, and Hamata to investigate OC and sediment properties along depth intervals to 1 m deep. Additionally, OC stored in the above- and below-ground biomass was estimated using Landsat 9 OLI/TIRS satellite images. TOC content (∼0.50%) and stocks in the sediments (54.49 ± 31.71–86.00 ± 29.00 MgC/ha) were very low compared to the global average for mangrove stands, and comparable to the mangrove forest in the Middle East region. This can be attributed to the desert and semi-desert conditions, limited riverine input, and low precipitation rates. Moreover, the above-ground biomass, estimated from Normalized Difference Vegetation Index, exhibited extremely low OC storage. Therefore, the sediment acted as the main pool of organic carbon in these mangrove ecosystems. The research findings revealed that mangrove stands in Egypt exhibit low CSR, ranging from 11.94 to 18.02 g C m−2 year−1. Additionally, the study determined that the stable nature of mangrove stands in Egypt makes their annual CO 2 emissions negligible. Despite local studies suggesting otherwise, it is highly unlikely that mangroves in Egypt contribute to the climate mitigation related to CO 2 sequestration. Therefore, it is important to implement restoration plans to ensure the preservation of other ecological services provided by mangroves along the Red Sea Coast. • Sediments OC stock ranged from 54.49 ± 31.71 to 86 ± 29 Mg C/ha, in 1m-cores in mangroves of Egypt. • Above- and below-ground carbon stock ranged from 0.08 to 0.45 Mg C/ha as estimated by Landsat 9 OLI/TIRS satellite. • CSR ranged from 11.97 to 18.02 g OC/m2/year. • Mangroves of Egypt showed insignificant contribution to climate mitigation related to CO 2 sequestration. [ABSTRACT FROM AUTHOR]

• First study to comprehensively address climate strategies for the O&G upstream sector in Brazil. • Decarbonization scenarios are simulated using a national Integrated Assessment Model (IAM). • O&G production can be sustained without compromising national decarbonization goals, but CO 2 and CH 4 emissions reductions must exceed simulated efforts to match industry leaders. • Ample potential to offset emissions through reforestation (∼ 500MtCO 2 /2050) and BECCS (∼ 400MtCO 2 /2050), presenting appealing business prospects for the industry. • CCS can play a vital role in advancing the decarbonization goals of both the sector and the country. Future projections of oil and gas demand suggest that some production will remain necessary. Although attention often focuses on CO 2 emissions from the combustion of their products, oil and gas production is also a relevant global emission source of both CO 2 and CH 4. Hence, understanding the carbon performance of upstream activities in producing nations is vital for distinguishing producers in a climate-pressured global market. This work explores climate strategies for the oil and gas upstream sector, using Brazil as a case study. The sector´s emissions profile is evaluated under distinct national climate scenarios. The analysis employs BLUES, a national Integrated Assessment Model (IAM), to access production volumes, mitigation measures applicable to the sector, and carbon dioxide removal potentials within the country to eventually offset the sector's remaining emissions. Results indicate sustained oil and gas production over the evaluated horizon (2020–2050) without compromising national climate goals, yet the sector's future emissions trajectory does not align with decarbonization targets pursued by more ambitious oil-producing nations and industry players. Despite sectoral mitigation measures indicated by the model, considerable emissions remain until 2050. Conversely, the country offers ample offsetting opportunities with potential synergies for the sector, especially through BECCS. Furthermore, the acceptability of offsets is discussed. [ABSTRACT FROM AUTHOR]

• The maximum pressure-limited global storage achievable after thirty years of continuous injection is 3640 GtCO 2 (121 GtCO 2 yr-1), increasing to 5630 GtCO 2 (70 GtCO 2 yr-1) at the end of the century. • Applying simplified physics models to estimate injectivity limited storage resources and rates allows for a self-consistent estimate of storage resources across the globe, resolved at the scale of geological basins, and including areas where no resource assessments have yet been carried out. • To achieve the global storage injection rates implied by scaleup trajectories included in the IPCC sixth assessment Report, injectivity limitations mean that deployment will have to expand beyond the ten countries with the most active CCS development today. Limiting global warming to a 2 °C rise may require large-scale deployment of carbon capture and storage (CCS). Due to the key role CCS plays in integrated assessment models of climate change mitigation, it is important that fundamental physical constraints are accounted for. We produce a global estimate of CO 2 storage resource that accounts for pressure-limits within basin-scale reservoir systems. We use a dynamic physics model of reservoir pressurisation that is sufficiently simple to be incorporated into energy systems models. Our estimates address regionally inconsistent methodologies and the general lack of consideration for pressure limitations in global storage resource estimates. We estimate a maximum pressure-limited resource base and explore scenarios with different injection patterns, and scenarios where the extent of CCS deployment is limited by the history of regional hydrocarbon exploration and the readiness of countries for deployment. The maximum pressure-limited global storage achievable after thirty years of injection is 3640GtCO 2 (121GtCO 2 yr-1), increasing to 5630GtCO 2 (70 GtCO 2 yr-1) at the end of the century. These represent an update to volumetric-based estimates that suggest in excess of 10,000Gt of storage resource available. When CCS deployment is limited to the top ten countries ranked by the GCCSI Storage Readiness Index, our maximum storage estimate decreases to 780GtCO 2 (26GtCO 2 yr-1) at the mid-century and 1177GtCO 2 (15GtCO 2 yr-1) at the end of the century. These latter results fall within the range of projected deployment by the IPCC and IEA and suggest that reservoir pressurisation will limit CCS deployment if development does not rapidly expand beyond the current implementation. [ABSTRACT FROM AUTHOR]

• Localized socioeconomic and natural narratives are applied on the regional scale. • Propose ecological zoning management in mountainous agglomerations. • POP, GDP, DEM, and Slope have an inverted U-shaped relationship with carbon storage. • Urbanization expands into the western mountainous under the localized SSP5–8.5 narrative. Ecological carbon storage is critical to climate change mitigation by absorbing CO 2 from the atmosphere. Mountainous ecosystems, crucial carbon reservoirs, are experiencing persistent carbon storage declines, yet management mechanisms targeting such complex terrains remain challenging. Focusing on the Sichuan-Chongqing urban agglomeration, interwoven as mountains and basins, we employed the MPI-coupled (Improved Markov-PLUS-InVEST) model and localized "socio-economic-climatic" narratives to simulate the dynamic evolution of carbon storage over extended periods. Diverse impacts and gradient effects of social, economic, and natural (incl. terrain, climate) drivers on carbon storage are further examined. The findings revealed that: (1) The most carbon storage growth projected from 2030 to 2060 reaches 1.53 %, but of which localized SSP5–8.5 narrative the urbanization encroached upon the undeveloped mountainous, severely impairing carbon sequestration by 81.5Tg. (2) In addition to landscape types, carbon storage exhibits complex spatial responses to economic development, population size, and terrain with an inverted U-shaped relationship. The proposed methodology offers more accurate carbon storage estimates and assists policy-makers in similar terrains to effectively manage the spatial heterogeneity of carbon storage. This study facilitates the implementation of tailored ecological conservation through urban zoning, thus contributing to enhanced subregional climate change mitigation efforts globally. [ABSTRACT FROM AUTHOR]

Effective municipal solid waste (MSW) management is a crucial component for sustainable cities, as inefficient waste disposal contributes to the release of about a billion tons of CO 2 -eq in greenhouse gases (GHG) annually. With escalating global waste generation, there is an untapped opportunity to integrate carbon dioxide removal (CDR) technologies into existing MSW management processes. This review explores current research on utilizing MSW for CDR, emphasizing its potential for both energy generation and carbon sequestration. The investigation covers three waste management practices: landfilling, waste-to-energy (WtE), and biochar production, revealing two paths for carbon sequestration. First, MSW serves as a feedstock in bioenergy with carbon capture and storage (BECCS), acting as a carbon-neutral resource that avoids fossil fuel and energy crop use, reducing GHG emissions and generating value through energy production. Second, direct storage of organic MSW and its derivatives, like biochar, in various carbon sinks allows for extended sequestration, offering a comprehensive approach to address the challenges of waste management and climate change mitigation. Moreover, this review advocates for an extended exploration into several subjects including in-depth analysis of waste, research on MSW-derived biochar recalcitrance across different carbon sinks, and understanding the symbiotic connections with GHG-emitting sectors like agriculture and energy. Finally, this review emphasizes the necessity of conducting life-cycle assessment studies to fully discern the benefits and assess the impacts of any future endeavors exploring the role of MSW in carbon sequestration. [Display omitted] • Municipal solid waste (MSW) is an untapped resource for carbon dioxide removal. • Three strategies to utilize MSW for CO 2 removal include landfilling, waste-to-energy, and biochar production. • Carbon sequestration is achieved through MSW-burial and energy recovery with CCS. • Auditing carbon emissions and LCA are necessary to illuminate the impacts of MSW. [ABSTRACT FROM AUTHOR]

• Revealing regional differences in the drivers' contribution to global carbon sequestration and oxygen release is urgent. • Regional differences may cause drivers' contributions to carbon sequestration and oxygen release to offset each other. • Clarified the scale transmission of the drivers underlying carbon sequestration and oxygen release. • Provides a conceptual framework and decision-making aid to address the negative impacts of global climate change. • Climate change decision-making needs to consider both top-down and bottom-up scaling transmissions. Understanding the scale transmission of the drivers underlying carbon sequestration and oxygen release (CSOR) is essential for climate change mitigation. However, the regional differences in the global contribution of the drivers remain unknown, limiting the effectiveness of climate policies. Based on the United Nations' geographical divisions and data from 2000 to 2020, we show that vegetation, evapotranspiration, and temperature are the main contributors to CSOR in more than 70 % of the world and that there are spatial differences in their action direction (facilitating or inhibiting). Drivers show nonlinear effects on CSOR and have different thresholds in different regions. Significant interactions existed among the factors, either superimposed enhancement or mutual offset, depending on the regions. If regional differences in drivers' global contributions are neglected, attempts to address climate change in various regions may offset each other. Considering both top-down and bottom-up scale transmission can improve the effectiveness of policy objectives. [Display omitted] [ABSTRACT FROM AUTHOR]

• Energy & chemical inputs, biogenic emissions, and product substitutions dominate environmental performance of biorefineries. • More transparency needed for product substitution modelling to avoid misleading conclusions. • Biogenic carbon capture use/storage could enhance future climate mitigation efficacy of biorefineries. • Accurate representation of biogenic carbon cycling essential to identify role of biorefineries in net zero strategies. Anaerobic digestion (AD) has gained attention in the last decade as a strategic component of the circular bioeconomy (CBE), and Life Cycle Assessment (LCA) has been used to explore the environmental performance of prospective AD-biorefineries. A detailed review of 76 studies underpinned systematic evaluation of environmental hotspots and LCA modelling challenges for AD-biorefinery configurations. Crops constitute the most frequently used feedstocks, while electricity, bioethanol, digestate, animal feed, additives, and platform chemicals represent the most reported products. Feedstock cultivation, energy and chemical inputs, biogenic emissions, and avoided burdens due to product substitution are the main drivers of environmental performance. However, modelling of product substitution, biogas upgrading, digestate management and biogenic carbon cycling is patchy, inconsistent, and often inadequately evidenced. Prospective and dynamic LCA coupled with transparent scenario analysis could address some of these shortcomings, and better represent, inter alia , the climate mitigation efficacy of carbon capture use and storage technologies integrated into AD-biorefineries. These findings provide a guide for LCA practitioners and researchers engaged in the study of biorefinery systems and other CBE measures. [ABSTRACT FROM AUTHOR]

CO 2 concentration in the atmosphere has crossed an unprecedented level of 420 ppm, causing catastrophic events like climate change. Climate change mitigation via carbon capture is crucial for reducing CO 2 emissions. Among various CO 2 capture technologies, adsorption is considered one of the most efficient and promising techniques. In recent times, substantial research has been conducted on producing cost-effective and efficient adsorbents for CO 2 capture via the thermal and chemical treatments of biomass. In this review, we discuss key scientific results to give broad insight into the recent progress in biomass conversion to activated porous carbon (APC). The effects of various chemical and thermal treatments on the textural properties and CO 2 adsorption capacity of APC are comprehensively discussed. CO 2 adsorption mechanism based on interaction with the surface functionality is thoroughly explained. The economic aspects of APC synthesis and post-combustion CO 2 capture using APC are systematically reviewed. [Display omitted] • Use of biomass based activate porous carbon (APC) for CO 2 capture is reviewed. • CO 2 adsorption mechanism on APC surface is thoroughly explained. • APC surface functionalization via metal doping and heteroatom doping is discussed. • Economics of APC synthesis & large-scale CO 2 capture on APC is critically reviewed. [ABSTRACT FROM AUTHOR]

This research aims to explore the current evidence on the sustainability of Bioenergy with Carbon Capture and Storage under a life cycle approach and to understand how research on this topic has evolved in the last decade. A systematic literature review was performed, and the main focus was identifying methodological shortcomings and analysing Global Warming Potential results. Forty-seven studies were selected for in-depth revision. Results show that the number of Life Cycle Assessment (LCA) studies on BECCS has increased in the last couple of years and that most of these studies report near-carbon neutral or carbon-negative results for electricity, biofuel energy, and other products. However, in many cases, some aspects have been omitted from the discussion, such as proper accounting of land use impacts, impact allocation procedure, accounting of leakage from storage sites, and impacts related to carbon utilisation. Despite this methodological variability, Global Warming Potential results are mostly carbon-negative and carbon-neutral for both power BECCS and industrial BECCS systems. Consequently, current scientific evidence suggests climate change mitigation benefits from BECCS despite methodological variability. However, it is still insufficient to reach a consensus on the sustainability of this technology as a solution for a global energy transition. It is recommended that further LCA research deals carefully with methodological and product systems variability, which may affect environmental impact results. Moreover, carbon capture approaches with high potential benefits should be further analysed, and the most optimal BECCS typologies should be identified. Finally, additional life cycle impact categories should be reported, along with the assessment of the economic and social dimensions of BECCS. [Display omitted] • Life Cycle Assessment (LCA) of Bioenergy with Carbon Capture and Storage (BECCS) was reviewed. • LCA methodology choices were discussed. • Global Warming Potential ranges between −3.873 and 0.366 kg CO 2 eq per MJ. • Current evidence is insufficient to confirm that BECCS is a sustainable solution for climate change mitigation. [ABSTRACT FROM AUTHOR]

Mangroves are under immense anthropogenic pressures globally which are further exacerbated by their accessibility to humans. To minimize human access hence pressures to the ecosystem, establishment of protected areas is often employed. However, the ecological effectiveness of protected areas, which influences their legal durability, is rarely assessed beyond curbing deforestation. Furthermore, little is known about whether protection could still provide a positive ecological impact if the sites are easily accessible, i.e., adjacent to urban areas, near roads, small in area and/or fragmented. To improve our understanding thereon, this study compares anthropogenic disturbance severity, forest structures and ecosystem carbon (C) stocks of protected and unprotected mangroves near Barranquilla, Colombia's largest coastal city. The outcomes suggest that accessible, yet protected mangrove has a mean disturbance index of 5.3, lower than unprotected mangrove (mean 11). Protected mangrove also has higher mean (± SD) tree basal area (26.5 ± 15.6 m2 ha−1), mean densities of tree, sapling and seedling (899 ± 398, 5155 ± 7860, and 68,837 ± 73,899 individual ha−1, respectively) and biomass C stock (mean 89.5 ± 39 Mg ha−1) than those of accessible unprotected mangrove (mean basal area 19.3 ± 5 m2 ha−1; mean tree, sapling and seedling densities 823 ± 215, 749 ± 94, and 33,727 ± 44,882 individual ha−1, respectively; mean biomass C stock 60.2 ± 14.5 Mg ha−1). Results suggest that the current sediment C stocks, that is higher in unprotected than protected mangroves (396.8 ± 552.6 and 142.4 ± 205.7 Mg ha−1, respectively), are not primarily driven by conservation status, but by long-term processes that likely pre-date the protected status designation. Mangrove protection, however, could help maintain carbon stocks in soils and biomass and the potential for further soil carbon sequestration, and thus are pivotal in determining future trajectories of mangrove climate mitigation potential. This study shows that even imperfect protection offers ecological benefits to highly accessible ecosystems. Hence, focus should be placed on optimizing these benefits and minimizing their vulnerability to downgrading, downsizing and degazettement. • influence of protection on mangroves is assessed beyond curbing deforestation. • protection effectively limit anthropogenic disturbance on mangroves. • protection promotes mangrove biomass C and regeneration potential. • mangrove sediment C stocks is largely influenced by sediment properties. • mangrove protection is ecologically beneficial even for highly accessible systems. [ABSTRACT FROM AUTHOR]

Carbon neutrality strategies have a significant role in climate mitigation efforts. As global concerns regarding climate change continue to increase, achieving carbon neutrality has emerged as a paramount objective for reducing greenhouse gas emissions and limiting the adverse impacts of anthropogenic activities on the environment. This research investigates a wide range of scholarly works to conduct an in-depth analysis and synthesis of the relevant information about carbon neutrality strategies. The review introduces carbon neutrality principles and terminologies, highlighting their importance in climate mitigation. It then proceeds to explore the wide range of strategies employed across different sectors and industries, investigating their effectiveness, scalability, and potential challenges. A multidimensional analysis contrasts the United States Nationally Determined Contributions pathway 2023, China's Nationally Determined contributions 2023, and the EU Directive 2023/2413, assessing their economic, environmental, political, and social impacts. The study evaluates strategies' effectiveness, scalability, and innovation for transitioning to a sustainable, low-carbon future. It fills a gap by analyzing global approaches across the US, China, and the EU, which account for about 50% of the world's total GHG emissions. It evaluates the novel application of diverse strategies, from renewable energy transitions to innovative policy measures, highlighting their potential to mitigate climate change effectively. By providing a multidimensional analysis of these strategies' impacts, the research not only enhances understanding of effective carbon neutrality tactics but also underscores the importance of international cooperation in realizing a sustainable, low-carbon future. • Identifies and analyzes carbon neutrality strategies, emphasizing the need for diverse US, Chinese, and EU approaches. • Evaluate renewable energy, carbon capture, and policy tools for carbon reduction effectiveness, scalability, and innovation. • Highlights the study's novelty in synthesizing current knowledge on carbon neutrality, addressing a significant research gap. • Concludes with strategic ideas for international collaboration and policy development for low-carbon futures. [ABSTRACT FROM AUTHOR]

Carbon capture and storage (CCS) in basalt is being actively investigated as a scalable climate change mitigation option. Accurate geochemical modeling prediction of the extent and rate of CO 2 mineralization is a critical component in assessing the local and global feasibility and efficacy of this strategy. In this study, we review basalt-CO 2 -water interaction experimental studies conducted during the last two decades to determine whether they provide useable information for geochemical modeling. Most of the cited experiments generate data on the temporal evolution of water composition, and a few provide identification of secondary precipitates and their compositions, offering information about the reactivity of basalts and the likelihood of secondary carbonate mineralization at various temperatures, pHs, and p CO 2 conditions. However, most experiments provide insufficient information on the properties and quantity of secondary minerals formed, prohibiting accurate mass balance calculations and hence more quantitative geochemical modeling studies. Primary Ca, Mg, and Fe-bearing minerals in basalt control the availability of major ions released into aqueous solution for carbonate precipitation, and many secondary minerals, i.e., smectites, Ca-Mg-Fe carbonates, and zeolites, provide sinks for the same major ions, some of which are difficult to quantify experimentally. Thus, we have a "multi-source and multi-sink" inverse mass balance modeling problem with insufficient constraints on the bulk system in which the temporal evolution of major ions does not provide sufficient information on which mineral(s) dissolve or the sequence of dissolution and precipitation reactions. Going forward, this review highlights the need for providing better-constrained experimental data to calibrate basalt-CO 2 -water geochemical models. Hence, we propose that future experimental work should focus on trace elements and multiple isotopic tracers as well as emphasize the need for better characterization of the solid reaction products with modern analytical instruments. [ABSTRACT FROM AUTHOR]

• CO 2 flows by forest dynamics and forest operations in one simulation tool. • Generic meta -model for plugging in any silvicultural concept of interest. • Freely available as an open source R-package on CRAN. Carbon stocks and flows in forest ecosystems play an important role in the context of climate change mitigation. Different aspects of the forest carbon balance, however, are often treated independently, leading to a fragmented, disciplinary knowledge. With the R-package care4cmodel we want to support a consolidated view of forest growth and forest operations with respect to carbon flows. The software is, in essence, a pragmatic simulation tool that allows juxtaposing the CO 2 uptake due to wood increment and the CO 2 emissions due to forest operations for given silvicultural concepts in an arbitrary area, over time. At the core, the approach is a dynamic forest area model where forest development stages are represented in a cyclical sequence, which can be broken by disturbances. The model scales up growth and yield information given per forest development stage and unit area to the dynamically simulated development stage areas. This allows to quantify the total forest area's CO 2 uptake, and to estimate the CO 2 emissions caused by forest operations. The forest operations in our implementation include the maintenance of the forest road network, felling trees, debranching and bucking the stems, and extracting the timber to a landing at a forest road. The transport from there to the industry is beyond the system boundary. For the CO 2 uptake of the forest system, the current model version focuses on the wood increment only. We use a practical example to demonstrate the basic features of the model and its plausible behaviour. Beyond the current focus of the model, we see a broad field of applications as a generic meta model, especially in the context of ecosystem service provision. [ABSTRACT FROM AUTHOR]

• Willingness to pay for BECCS in Denmark and factors influencing it are investigated. • Willingness to pay is linked to the view of BECCS as necessary for mitigation. • View of BECCS as a necessity reveals either support or reluctant acceptance. • Preference for renewable energies revealed by respondents unwilling to pay. • Age, views on climate change and sustainability of biomass influence WTP. Most climate change mitigation scenarios rely on negative emissions technologies like bioenergy with carbon capture and storage (BECCS). However, little is known about public support for BECCS. This paper gauges Danes' willingness to pay (WTP) for biomass with carbon capture and storage and examines factors influencing it. Denmark is a suitable case study given its reliance on biomass and negative emissions to achieve climate targets. Results from a questionnaire-based survey indicate a mean WTP of 3072 DKK (412 EUR) per household per year. This correspondents to a 12% increase in heat and electricity expenses. The need for negative emissions is the main stated reason for WTP. This may be interpreted as reflecting either support for, or reluctant acceptance of, BECCS. Results show that being younger, being concerned about climate change and believing that it is mainly caused by human activity, and believing in the mitigation potential of biomass and that sustainability is a precondition of its use have a significant effect on WTP. Public views on BECCS are complex but must be acknowledged if discussion of the role of BECCS in the decarbonisation agenda is to move forward. [ABSTRACT FROM AUTHOR]

• Analyses CCS technological innovation system dynamics in Norway. • Employs the technological innovation system (TIS) framework. • Overall the CCS innovation system has intermediate-weak performance. • Momentum is however positive, albeit future prospects being uncertain. CO 2 Capture and Storage (CCS) is today seen as a key technology to cut carbon emissions in many hard-to-abate sectors such as energy-intensive processing industries and the waste sector. Although CO 2 capture is technically possible, key challenges for realizing CCS persist. Over the past decade, CCS has taken a new direction with more focus on application in energy-intensive industries rather than the energy sector. For CCS value chains to materialize, innovation and implementation thus needs to occur amongst an array of actors, with different innovation modes, institutions, and policy regimes, and with varying sectoral capacities for adaptation and change. There has so far been limited social science research on CCS innovation dynamics, which we suggest approaching as a socio-technical change process. To better understand this process, we draw on the sustainability transitions research field and employ the Technological Innovation System (TIS) framework to study the CCS innovation system in Norway. We find that, overall, the Norwegian CCS TIS displays systemic weaknesses for example in the form of market formation and resource mobilization, yet recent developments suggest a relatively positive momentum for this technological field which is key to meeting Norwegian and global climate mitigation targets. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) is a critical measure for ecosystem health and offers opportunities to understand carbon fluxes and associated implications. However, SOC can be significantly influenced by anthropogenic land use change, with intensive and extensive disturbances resulting in considerable SOC loss. Consequently, understanding the spatial distribution of SOC across different land uses, particularly at national level characterised by different biomes, is vital for integrated land-use planning and climate change mitigation. Remote sensing and deep learning (DL) offer a reliable largescale mapping of SOC by leveraging on their big data provision and powerful analytical prowess, respectively. This study modelled SOC stocks across South Africa's major land uses using Deep Neural Networks (DNN) and Sentinel-3 satellite data. Based on 1936 soil samples and 31 spectral predictors, results show a relatively high accuracy with an R2 and RMSE value of 0.685 and 10.15 t/h (26% of the mean), respectively. From the seven land uses evaluated, grasslands (31.36%) contributed the most to the overall SOC stocks while urban vegetation (0.04%) contributed the least. Moreover, although SOC stock was found to be relatively proportional to land coverage, commercial (46.06 t/h) and natural (44.34 t/h) forests showed a higher carbon sequestration capacity. These findings provide an important guideline to managing SOC stocks in South Africa, useful in climate change mitigation through sustainable land-use practices. Whereas landscape restoration, and other relevant interventions are encouraged to improve SOC storage, care must be taken within land-use decision making to maintain an appropriate balance between carbon sequestration, biodiversity, and general ecosystem functions. [ABSTRACT FROM AUTHOR]

Small Island Developing States (SIDS) face complex socio-economic and environmental threats, making them particularly vulnerable to climate change. Blue Carbon (BC) ecosystems (mangrove forests, tidal marshes, and seagrass meadows) provide climate regulation services by sequestering and storing carbon, presenting an opportunity for SIDS to address climate change and implement Paris Agreement commitments in their Covid-19 recovery. BC habitat decline not only reduces carbon sequestration benefits provided, but can also result in sediment disturbance and the release of previously stored carbon back into the atmosphere. In this work, a scenario analysis informed by a stakeholder workshop and scientific and socio-economic expectations is used to assess the economic importance of Grenada's BC (mangroves and seagrasses) over the next 10, 25 and 50 years. Our findings indicate that sequestration benefits are severely diminished under Business-as-Usual habitat loss, but still marginally outweigh losses from carbon emissions, with overall welfare gains of US$0.5–1.9 million over 50 years. To stimulate economic recovery post-pandemic, stakeholders anticipated a realistic scenario of increased habitat decline resulting in overall losses of US$5.4–19.4 million in the next 50 years. However, if ecosystems are maintained, overall carbon benefits could reach US$10.7 million, while a 20% increase in mangroves over the next 25 years provides benefits reaching US$11.1 million between 2020 and 2070. These results demonstrate a significant increase in value when BC ecosystems are maintained and not disturbed, preventing the release of previously stored carbon and enhancing sequestration capacity. Restoration benefits are marginal, compared to conservation, supporting claims that conservation is more cost effective. • A scenario analysis is used to value Grenada's BC climate mitigation service. • Maintaining BC extents retains sequestration worth up to $10.7million over 50 years. • BAU habitat loss lowers sequestration and releases stored carbon, reducing benefits. • More severe habitat declines result in welfare losses up to US$19.4million by 2070. • Integrating BC into SIDS' Paris Agreement commitments can enrich climate mitigation. [ABSTRACT FROM AUTHOR]

Rising greenhouse gas emissions, especially CO 2 , intensify global warming. Carbon Capture and Storage (CCS) is vital for reducing emissions from industrial sources, crucial for addressing climate change urgently. This study explores reservoir characterization challenges for CCS in the Penobscot field, offshore Nova Scotia. We used to cross-plots of geophysical logs to establish relationships between petrophysical properties and subsurface litho-facies, differentiating sand and shale facies within the Mississauga Formation (Early to Middle Cretaceous). Seismic impedance inversion distinguished between reservoir and non-reservoir facies. Multi-attribute assisted transformed seismic data and a support vector machine algorithm predicted litho-facies probabilities and effective porosity volumes in 3D space. The permutation predictor importance analysis was performed to assess the relative importance of input features in facies probabilities and effective porosity prediction. The structural component delineated the CO 2 injection trap boundary. Integrated analysis of structural configuration, litho-facies probability, effective porosity, and cap-rock sealing integrity validated zones for CO 2 storage. The dry, abandoned well L-30 in the structural high zone is recommended as a pilot CO 2 injector well. This study provides critical insights into reservoir characterization for CO 2 sequestration, aiding climate change mitigation through effective CCS, and recommends geomechanical studies and time-lapse seismic monitoring. • Identified promising sites for CO 2 storage in Penobscot field, Canada Offshore. • Predicted impedance, facies probabilities, and effective porosity with high accuracy. • Enhanced discrimination between the reservoir and non-reservoir facies. • Assessed lithological and petrophysical characteristics of the reservoir and cap rocks. • Emphasised storage site identification as a strategy to mitigate climate change. [ABSTRACT FROM AUTHOR]

• Intercropping with reduced N input increases deep C storage while reducing GHG emissions. • Double-legume rotation increases C content in management-sensitive SOC pools. • Alley cropping in Mediterranean regions achieved the goals of 4 ‰ initiative. • Deep burial of straw sequestered SOC primarily by increasing POC and MAOC. • No-till maintains soil quality more than it mitigates climate change. [ABSTRACT FROM AUTHOR]

Decarbonizing the EU's district heating is crucial for meeting climate goals and securing a sustainable energy future. Currently, district heating suffers from inefficiency, high operating temperatures, significant distribution losses, and reliance on fossil fuels. Literature highlights strategies for reducing emissions, including integrating low-carbon heat sources, lowering supply temperatures, and employing efficient technologies like heat pumps and combined heat and power (CHP). However, the individual effectiveness of these strategies in reducing emissions within existing networks remains unassessed. This study addresses the gap by applying a comprehensive model that evaluates energy and emissions across the district heating supply chain, coupled with a derivative-based sensitivity analysis. We apply this methodology to the national-level district heating systems of Sweden, France, Germany, and Poland. Results indicate that the impact of decarbonization strategies on district heating emissions varies significantly by the system's characteristics, i.e., the energy mix in power and district heating supply and the presence of CHP plants. Primarily, incorporating more low-carbon heat sources emerges as the most effective method for emission reduction across nearly all examined countries. A 1 % increase in the share of low-carbon heat sources can potentially cut emissions by 0.8–1.3 kg CO 2 e per GJ of heat. In countries like Sweden and France, where the power generation already relies heavily on low-carbon resources, technologies which convert electricity to heat—such as heat pumps and electric boilers—rank as the second most effective approach. In contrast, for countries like Germany and Poland, with their moderate to low use of low-carbon power, reducing distribution losses and decreasing heat demand prove more effective, with emission reductions ranging between 0.8-1.3 and 0.7–1.2 kg CO 2 e per GJ in these countries, respectively. Additionally, cutting down power generation in fossil fuel-based CHP plants significantly reduces emissions in these regions. While green hydrogen and carbon capture and storage (CCS) also contribute to emission reductions, a 1 % increase in green hydrogen's share might decrease emissions by just 0.3–0.5 kg CO 2 e per GJ of heat, highlighting their lower effectiveness compared to the aforementioned strategies. These insights hold value for both district heating operators and for technology suppliers seeking decarbonization pathways. This is also true for policymakers focused on climate change mitigation, guiding the distribution of subsidies and R&D investments. • Creation of a framework to evaluate the effectiveness of strategies to reduce emissions in district heating. • Application of the method to the national-level systems of Sweden, France, Germany, and Poland. • Effectiveness of strategies varies significantly by the system's characteristics. • Identification of most effective strategies by country and policy recommendations. [ABSTRACT FROM AUTHOR]

Cocoa production is a leading driver of deforestation in the humid-tropics of West Africa. Reconciling climate change mitigation with livelihoods of farmers requires identification of production strategies to concurrently improve yield and profit while curtailing emissions of greenhouse gases (GHG). Using a 2021 plot-survey conducted in Ghana's Eastern region, we evaluated yields, GHG emissions, and value of production (VOP) (a profit indicator) across a typology representing the diversity of systems at plot-level. The typology was constructed by first stratifying plots according to shade levels and variety (hybrid vs. Amazonia) which resulted in three systems: Hybrid sun , hybrid variety under full-sun (little to no shade); Hybrid shade , hybrid and moderate shade (13–25 shade trees ha−1); and Amazonia, Amazonia under predominantly moderate shade. Next, factor analysis and clustering were used to group plots within each system according to cocoa yield, vegetation, management, and (local) climate conditions. Cluster analysis showed that fertiliser, weeding, pruning, hand pollination, cocoa tree density, and shade tree densities of differing heights were most influential for determination across systems. Hybrid shade had the highest net GHG removal rate at −6.8 ± 1.7 (± 95% CI) Mg CO 2 eq ha−1 yr−1: 48% and 127% higher (emissions more negative) respectively over Amazonia and Hybrid sun. Hybrid shade additionally had the highest average and least variable VOP among production systems at 669 ± 564 USD ha−1 yr−1, compared to Hybrid sun and Amazonia at 404 ± 442 and 213 ± 280 USD ha−1 yr−1 respectively. These results point to hybrid cocoa grown under moderate shade of 13–25 shade trees ha−1 as optimal for reconciling climate change mitigation with development in West African cocoa. • Study concurrently evaluates financial profits and GHG balances (N 2 O & CH 4 emissions, CO 2 removals) in West African cocoa. • Plot-level indicators are evaluated across a typology obtained from sample-stratification and clustering. • Hybrid cocoa under moderate shade (13-25 shade trees ha-1) had GHG removal increment of 127% over same variety without shade. • This system too had higher mean profits, thus best reconciling GHG mitigation and economic development for the region. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of amine-impregnated polymer aerogels for CO 2 capture represents a groundbreaking advancement in combating the urgent challenges of carbon dioxide (CO 2) emissions and climate change mitigation. The traditional way of synthesizing aerogels for CO 2 capture is to use a one-step gelation process without functionalizing the aerogel, which, to some extent, has low CO 2 capture capacity and kinetics. This study finds a method of synthesizing the functionalized aerogel, which has high CO 2 adsorption capacity, faster kinetic, and is more stable. The polymer aerogel was developed using an oil-water emulsion polymerization method, followed by freeze-drying. It was impregnated with a mono-ethanolamine (MEA) solution to enhance CO 2 adsorption. The performance of the amine-impregnated poly (AAm-co-AAc) aerogels was tested in a continuous adsorption column filled with aerogel. The adsorption results showed the amine-impregnated aerogels having an amine equilibrium uptake value of 40% had significantly improved CO 2 capture capacity up to 2.34 mmole g−1 at 1 bar pressure, 25 °C reaction temperature, and 10 ml/min flow rate. The polymeric aerogel has a very fast adsorption rate, as it can capture 90% of its maximum capacity within just 10 minutes. Then the kinetic data of the CO 2 adsorption was modelled and found to best fit on both pseudo-1st and 2nd-order kinetic models, proposing that the adsorption mechanism on aerogel was controlled by surface diffusion and chemisorption. Furthermore, the isotherm data were evaluated and observed to be best represented by the Langmuir isotherm model, suggesting monolayer formation on the aerogel. After five adsorption-desorption cycles, the amine impregnated poly (AAm-co-AAc) aerogel was able to preserve the initial capacity without a significant decrease. These findings underscore the immense ability of amine-impregnated poly (AAm-co-AAc) aerogels as highly efficient adsorbents for CO 2 capture, thus offering a speedy adsorption process and showing stable regeneration capacity, thereby exhibiting greater industrial application potential. [Display omitted] • An emulsion polymerization method was used to synthesize aerogels for CO 2 capture capacity. • The morphology of the aerogel is fibrous, contributing to its high amine uptake. • Its CO 2 adsorption capacity is up to 2.34 mmole g−1 at 25°C, and regeneration stability is five cycles. • The aerogel exhibits a rapid adsorption rate, capturing 90% of its capacity within 10 minutes. [ABSTRACT FROM AUTHOR]

The Andalusian olive grove in South Spain is employed as a case study to assess the environmental and economic effects of the green architecture (eco-schemes) of the Common Agricultural Policy in relation to low carbon agriculture under different soil management policy scenarios to support more efficient agri-environmental policy making. To do so, we adopted a multidisciplinary approach in which we used: (i) an integrated modelling framework comprising geographic information systems (GIS); (ii) the RothC model; and (iii) a cost-benefit analysis. Results show that eco-schemes provide a significant increase of soil organic carbon (SOC) relative to cross-compliance. Practices involving vegetation covers are more efficient than using pruning residues as mulching. SOC accumulation increases rapidly in the first five-ten years to slow down afterwards. The cost-benefit ratios of eco-schemes policy implementation are higher than one when only SOC is considered. Nonetheless, the inclusion of additional co-benefits has the potential to invert this scenario and enhance policy efficacy. Various insights on optimizing the design and application of eco-scheme efficiency are provided. • The new eco-schemes CAP instrument proposed for woody crops contribute to increase SOC • Mowing cover crops leads to the highest SOC stocks, whereas pruning debris maintains SOC stocks. • Tillage and no-tillage with bare soil systems lead to a significant depletion of SOC stocks. • The economic benefits of eco-schemes would not off-set the costs borne by public authority • Environmental externalities are key to reach the profitability of the policy instruments. [ABSTRACT FROM AUTHOR]

Residential green spaces are an integral part of urban green infrastructure and its role in climate change adaptation and mitigation. Various urban typologies and changing planning practices affect the amount and structure of residential greenery, which has a direct impact on climate benefits. While urban green and its climate benefits have received increasing attention, there is still limited knowledge on how changing planning practices and related urban typologies impact residential vegetation and its capacity to deliver climate benefits. This paper aims to address this gap by determining the impact of planning practices on residential vegetation, focussing specifically on climate mitigation and adaptation. With the case study of Helsinki, characterized by a high share of green areas, the paper first examines how construction year and urban density affect the amount and structure of vegetation on residential properties. Second, it estimates the carbon sequestration and summer temperatures in the present-day climate. The paper applies spatial modelling and regression analysis to estimate the impact of construction year on the studied dependent variables, while controlling density via gross floor area of buildings. The study demonstrates that the average amount of residential vegetation, as measured using canopy and vegetation cover, has declined 15 percentage points from the 1970 s to early 2010 s and the canopy to low vegetation ratio has decreased constantly over the periods studied. The decline of the canopy cover in particular has reduced the climate benefits of residential vegetation. The paper highlights the significant impact of gross floor area and planning practices on urban vegetation cover and the climate benefits it provides. It also stresses the importance of ensuring sufficient tree cover and permeable surfaces in cities with progressive climate mitigation agenda throughout the chain of urban planning, construction, and subsequent property management stages. [Display omitted] • Residential areas are a vital but understudied part of urban green infrastructure. • The amount of residential vegetation has diminished since the late 1970 s • The decline in canopy cover has reduced the climate benefits of residential areas. • Density and spatial patterns affect the climate benefits of residential vegetation. • Climate-wise, residential areas require sufficient vegetated and permeable surfaces. [ABSTRACT FROM AUTHOR]

• CO 2 injection for EOR in shales can be optimized to adapt CO 2 storage simultaneously. • Dual-lateral wells improved oil recovery by 26 % more than Huff-n-Puff and stored an extra 62 % of the injected CO 2. • The optimization design of the dual lateral injection improved NPV. • Well vertical separation showed a high impact on the efficiency of the injection. The dual challenge of enhancing oil recovery while sequestering carbon dioxide (CO 2) in oil reservoirs is a pivotal concern in the energy sector. CO 2 injection is recognized for its ability to decrease oil density and viscosity, thereby improving oil mobility and recovery rates. Traditionally, efforts have been concentrated either on enhancing oil recovery (EOR) or carbon storage, but not many efforts spent to couple EOR and CO 2 sequestration. Hence, novel techniques to optimize engineering designs to synergize EOR with CO 2 sequestration is the best approach to maximize the opportunities of storing emission gas and contribute to the global world decarbonization goals. This study introduces an innovative dual lateral horizontal well design, aimed at simultaneously boosting oil recovery from shale reservoirs and enhancing CO 2 retention. By integrating a conceptual understanding of oil recovery mechanisms with empirical data from the field, this research contrasts the proposed dual lateral design with the conventional Huff-n-Puff gas injection technique, commonly employed in shale oil formations. Our findings demonstrate that the dual lateral horizontal wells significantly outperform other injection methods in both oil recovery and CO 2 storage. Upon optimization, the dual lateral injection design continues to surpass the Huff-n-Puff method in terms of CO 2 storage, oil recovery, and net present value (NPV). This investigation not only presents innovative gas injection strategies in shale reservoirs but also provides insights into optimizing gas injection methods to enhance production efficiency and contribute to climate change mitigation through improved carbon capture and storage capacities. Through comprehensive numerical simulations and empirical data analysis, the study explores the optimization of well spacing, revealing that a dual lateral well with optimized spacing between 20 and 30 feet achieves the best outcomes in terms of oil recovery, CO 2 retention, and net present value (NPV). The research presents a unique coupling of economic and environmental benefits, supported by economic analysis that includes the potential impact of CO 2 tax credits. The novelty of this research is underscored by its integrated approach to CO 2 -EOR, the development of a dual lateral well design, and the optimization of well spacings for maximized efficiency. By providing a scalable solution that is both economically viable and environmentally sustainable, this research contributes a significant paradigm shift in the field of EOR and CO 2 sequestration, with implications for policy and investment strategies in the energy sector. The findings propose a new direction for shale reservoir exploitation, promising to enhance production efficiency while contributing to global efforts in greenhouse gas reduction. [ABSTRACT FROM AUTHOR]

Achieving a precise assessment of the aboveground biomass (AGB) in mangroves is a critical foundation for sustainable management and carbon sequestration assessment within climate change mitigation strategies. Conserving existing mangrove forests can maintain and enhance AGB over time. This study used a support vector regression (SVR) model, and vegetation indices derived from Sentinel-2 data for a comparative analysis of mangrove AGB within conservation and restoration projects in Madagascar and Abu Dhabi Emirate. The results confirmed that the SVR model based on vegetation indices, once calibrated against the field inventory data, was effective for estimating mangrove AGB at project scale. For the Madagascar project, the model achieved an R2 of 0.81 and RMSE of 27.99 Mg ha−1 for the 2015 timepoint, and an R2 of 0.79 and RMSE of 32.82 Mg ha−1 for 2019. In Abu Dhabi, an R2 of 0.76 and RMSE of 20.51 Mg ha−1 in 2015 and R2 of 0.75 and RMSE of 22.29 Mg ha−1 in 2020 were obtained. The SVR model estimated a decline in AGB from 116.78 Mg ha−1 to 109.63 Mg ha−1 during 2015–2019 in Madagascar, representing a decrease of 7.15 Mg ha−1 (6.13%). While in Abu Dhabi, the average AGB was estimated at 37.51 Mg ha−1 in 2015 and 42.69 Mg ha−1 in 2020, indicating an increase of 5.18 Mg ha−1 (13.76%) which can be attributed to conservation efforts in this region. This study suggested that Sentinel-2 can facilitate the comparison of AGB changes before and after conservation efforts, enabling the quantification of long-term shifts in mangrove AGB. • The SVR model and vegetation indices obtained from Sentinel-2 was used for monitoring mangrove AGB changes. • Red, NIR, red-edge bands and SWIR2 demonstrated higher correlation with AGB. • The deforestation is major driver of the decrease in AGB in Madagascar Bay of Assassins. • Monitoring AGB is crucial for mangrove sustainable management and conservation. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are one of the most promising functional materials for CO 2 adsorption and transformation owing to their abundant active sites, easily functionalized surface, and highly adjustable pore structure, among others. This review discussed the recent research outputs in the synthesis and catalytic applications of MOFs – based nanocatalysts for CO 2 capture and conversion. The focus was on papers published in the last five years. The different synthetic methods of MOFs and MOF-based nanocomposites were elaborated. More so, the performance of MOFs as adsorbents in CO 2 capture and the proven performance enhancement strategies which include functionalization and compounding with other materials as nanocomposites were discussed in detail. Special emphasis was given to the different transformation routes of CO 2 viz. hydrogenation, photocatalysis, electrocatalysis, photoelectrocatalysis, and chemical fixation. As against what is obtainable in most similar reviews, the review provides insight into the application of MOF-based materials in integrated CO 2 capture and transformation. The work further provides an elaborate discussion of the current challenges and future perspectives. The reported works indicated that these MOF-based materials possessed the required competence for the adsorption and transformation of CO 2 into valuable products, making them excellent choices for practical applications. [Display omitted] • The uncontrolled release of CO2 into the atmosphere is a threat to human survival. • CO2 capture and transformation are one of the significant climate change mitigation options. • MOFs are one of the most promising functional materials for CO2 adsorption and transformation. • MOF synthesis methods are solvothermal, microwave-assisted, mechanochemical, electrochemical, and sonochemical. • CO2 transformation techniques are hydrogenation, photocatalysis, electrocatalysis, photoelectrocatalysis, and chemical fixation. [ABSTRACT FROM AUTHOR]

Existing assessments of climate mitigation technologies, like carbon capture utilisation and storage (CCUS), often rely on life cycle assessments (LCA), which are helpful for quantification but may not always be the most complete tools for decision-making. The novel contribution of this study is to provide the first application of a consequential carbon accounting approach, presented as a time-series analysis, to measure the system-wide change in emissions from CCUS linked to CO 2 -enhanced oil recovery. This method includes emissions from marginal oil production, a variable typically excluded in other LCA methods. The method was applied to a hypothetical CCUS project in Mexico to understand critical factors determining whether such an intervention can effectively contribute to emissions reduction in alignment with net-zero goals. Four intervention scenarios were assessed, comparing two distinct CO 2 injection strategies in oil reservoirs (water alternating gas and continuous gas injection) and two energy policy scenarios (current and sustainability). The findings suggest that the energy grid's role in overall emissions is relatively minor, with only a ∼2% difference between the compared scenarios, in contrast, the injection strategy has a significant impact on emissions. Scenarios 1 and 3 report a total change in emissions of −28.39 and −29.87MtCO 2 e, and scenarios 2 and 4 account for −19.63 and −21.22MtCO 2 e, respectively. The results highlight the importance of conducting system-wide analysis and comparing different scenarios to identify the critical components that drive changes in emissions and, therefore, support decision-making and project planning. • Consequential carbon accounting quantifies the system-wide change caused by CCUS. • A time-series provides decision-relevant information on climate change mitigation. • Market-mediated effects are highly relevant for CCUS projects. • CCUS is not consistent with net zero due to as remaining emissions. [ABSTRACT FROM AUTHOR]

Desertification, the process of land degradation in arid, semi-arid, and dry sub-humid areas, poses significant environmental, social, and economic challenges worldwide. As desertification continues to threaten ecosystems and livelihoods, innovative strategies for its management are urgently needed. The article begins by elucidating the causes and consequences of desertification, emphasizing its complex interplay with human activities and natural factors. It highlights the growing recognition of soil microbes as a critical component in combatting desertification. Soil microbes, encompassing a diverse community of bacteria, fungi, archaea, and other microorganisms, play multifaceted roles in soil health, ecosystem function, and sustainable land management. This review delves into the mechanisms through which soil microbes can contribute to desertification management. It discusses their roles in nutrient cycling, soil fertility enhancement, carbon sequestration, soil stabilization, erosion control, and biodiversity conservation. Drawing on case studies and real-world examples, it offers insights into successful applications of soil microbe-based strategies across different geographical regions and ecosystems. Challenges and limitations in implementing these strategies are also examined, including factors such as environmental variability, scale of application, and potential risks. Furthermore, research gaps and areas for improvement in understanding the intricate relationships between soil microbes and desertification management are identified. The review explores prospects and research directions in soil microbe-based desertification management. It highlights innovative approaches, emerging technologies, and the importance of interdisciplinary collaboration. Additionally, it discusses policy implications and the potential of these strategies to contribute to sustainable land use practices. [ABSTRACT FROM AUTHOR]

• The 57.00% of the Yangtze River Economic Belt area exhibited a significant increase in annual NPP. • The response of NPP on climate factors was nonlinear, with greater sensitivity to temperature. • The impact of topographic factors on NPP changes had a threshold effect. Net primary productivity (NPP) of terrestrial ecosystems serves as a crucial carbon sink, playing a significant role in mitigating climate change. This study, focusing on the Yangtze River Economic Belt (YREB), a key area for both economic development and ecological conservation in China, evaluates the temporal and spatial changes in regional NPP and its responses to climatic factors against the backdrop of global change. Utilizing long-term NPP and meteorological grid data from 1981 to 2017, we analyzed the annual change patterns of NPP and its linear and nonlinear responses to climatic factors using copula functions. Our findings indicate that 57.00 % of the YREB has experienced a significant increase in NPP, with the most substantial decreases observed in Shanghai and its surrounding areas (P < 0.05). Temperature emerged as the primary climatic driver, positively correlating with NPP changes in over half of the study area (P < 0.05). Moreover, the nonlinear response of NPP to temperature and precipitation underscores the complex interactions between these factors, revealing a sensitivity to temperature variations that surpasses that to precipitation. The study also highlights the influence of solar radiation and topographic factors, with a significant positive correlation between NPP and solar radiation observed in 15.85 % of the area (P < 0.05). The practical significance of these findings lies in their implications for regional ecological management and climate resilience strategies. The positive correlation between temperature and NPP underscores the potential for targeted temperature management to optimize carbon sequestration across the YREB. Furthermore, the identified nonlinear responses and the role of solar radiation and topography in influencing NPP offer valuable insights for the formulation of adaptive strategies that enhance ecosystem productivity and contribute to achieving carbon neutrality goals. By elucidating the dynamics of NPP in response to a range of environmental factors, this study provides a foundation for informed decision-making in ecological conservation and climate change mitigation efforts within the YREB and similar regions globally. [ABSTRACT FROM AUTHOR]

Boreal forests are often managed to maximize wood production, but other goals, among which climate change mitigation, are increasingly important. Hence, it is necessary to examine synergies and trade-offs between forest production and its potential for carbon sequestration and climate change mitigation in forest stands. To this aim, we develop a novel mass-balanced process-based compartmental model that allows following the carbon path from its photosynthetic fixation until its return to the atmosphere by autotrophic or heterotrophic respiration, or by being burnt as wood product. Following carbon in the system allows to account for how long forest ecosystems and wood products retain carbon away from the atmosphere (i.e., the carbon transit time). As example, we apply the model to four management scenarios, i.e., mixed-aged pine, even-aged pine, even-aged spruce, and even-aged mixed forest, and contrast metrics of performance relative to wood production, carbon sequestration, and climate change mitigation potential. While at the end of an 80 yr rotation the even-aged forests held up to 31% more carbon than the mixed-aged forest, the mixed-aged forest was superior during almost the entire rotation when factoring in the carbon retention time away from the atmosphere, i.e., in terms of climate change mitigation potential. Importantly, scenarios that maximize production or amount of carbon stored in the ecosystems are not necessarily the most beneficial for carbon retention away from the atmosphere. These results underline the importance of considering carbon transit time when evaluating forest management options for potential climate change mitigation. [Display omitted] • We evaluate wood production and climate change mitigation potential of boreal forests. • We combine an ecophysiological growth model with forest inventory tree allometries. • Higher carbon sequestration does not ensure higher climate change mitigation potential. • Potential climate change mitigation depends on carbon time away from the atmosphere. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hedgerows and adjacent croplands at 23 sites across Germany were sampled. • Under hedgerows, 36 ± 49 % more soil organic carbon (SOC) was stored compared to cropland. • 41 % of absolute SOC stock increase was found in subsoil below 30 cm soil depth. • SOC stocks were also increased along the transect from the hedgerow to the cropland. • Planting hedgerows on 3 % of German cropland could increase SOC stocks by 13 Tg C. Carbon dioxide removal strategies are becoming increasingly important as a fundamental component of comprehensive climate policies. One strategy to increase carbon (C) sinks is the integration of hedgerows into agricultural landscapes. Besides additional C storage in above-ground and below-ground hedgerow biomass, the establishment of hedgerows has the potential to increase soil organic carbon (SOC) stocks. However, empirical data regarding the magnitude of SOC accrual with hedgerow establishment are still limited. We sampled 23 sites across Germany in a paired-plot approach with the aim of estimating SOC stock change with hedgerow establishment on cropland. At 21 sites, SOC stocks were higher beneath hedgerows than in the reference cropland. On average, SOC stock accrual was 29 ± 22 Mg ha−1 (36 ± 49 %) in 0–100 cm soil depth. SOC stocks were significantly different in both topsoil and subsoil. Subsoils below 30 cm depth contributed 41 % (12 ± 17 Mg C ha−1) of the total SOC stock change, stressing the importance of subsoil SOC for the total SOC stocks of hedgerow systems. The positive effect of hedgerows on SOC stocks extended laterally beyond the hedgerow area itself. SOC stock in the grassy hedgerow edge also increased significantly by 22 ± 22 Mg C ha−1 (28 ± 30 %) and SOC stock in the cropland directly adjacent to the hedgerow were 9 ± 19 Mg C ha−1 (12 ± 25 %) higher than in the reference cropland. Particularly high C stock differences between hedgerows and reference cropland soils were found in old hedgerows (>200 years) planted on hedgebanks, which are typically found in northern Germany. Our study confirmed that SOC stocks increase with hedgerow establishment on cropland throughout the whole soil profile. If hedgerows were to be established on 3 % of Germany's cropland area, SOC stocks would increase by 13 Tg C equivalent 48 Mio. t CO 2 , highlighting that hedgerows are a promising and multi-functional climate change mitigation option. [ABSTRACT FROM AUTHOR]

Article 6 of the Paris Agreement establishes the foundation for international carbon markets by allowing Parties to cooperate to achieve their nationally determined contributions (NDCs). The Paris Agreement also embeds the concept of 'net zero' by calling for a balance between anthropogenic emissions of GHGs and removals of GHGs by sinks to be reached in the latter part of this century. All signatory Parties therefore tacitly acknowledge that meeting the Agreement's ambitious climate change mitigation goals relies not only on deep cuts in anthropogenic GHG emissions, but also on the offsetting of residual, hard-to-abate, GHG emission sources through significant increases in carbon removal from the active climate system and the storage of CO 2 in enhanced sinks and reservoirs. In these respects, Article 6 potentially offers a variety of routes to incentivize CO 2 capture and storage (CCS) including through emissions trading but also more novel means of cooperation that focus more specifically on carbon storage and which could potentially address some of the challenges posed for CCS over the past 15 years or so. In order to assess the status and outlook for Article 6 with a focus on CCS activities, we define three potential models for cooperation and undertake a comparative evaluation against the key criteria of effectiveness, environmental integrity, commercial and financial viability, progression and policy performance. We conclude with some observations regarding the factors that may influence the likelihood of these different market models evolving over coming years. [ABSTRACT FROM AUTHOR]

• A CGE model elaborately depicting six CCS technologies was developed. • Impacts of four CCS incentive scenarios on decarbonization pathways were simulated. • CCS can sequester 960 ∼ 1,604 MtCO 2 annually in China by 2060 with policy incentives. • CCS incentives can reduce China's future primary energy demand by 7.7 ∼ 17.4 %. • CCS incentives can increase GDP by 5.64 ∼ 6.59 % compared to no policy scenario. Carbon capture and storage (CCS) technology, considered as a pivotal tool in mitigating climate change within the fossil energy system, particularly in China, has experienced slower development than expected. The exploration of direct incentive policies to facilitate its growth remains relatively underdeveloped. This study developed a hybrid dynamic computable general equilibrium (CGE) model to simulate the substantial impacts of CCS incentive policies on China within the context of carbon neutrality target. Two potential incentive policies, carbon emission trading system (ETS) and 45Q tax credit, were simulated, with different sectoral coverage. The results indicate that CCS technologies can reduce carbon emissions by 960 ∼ 1,604 MtCO 2 annually by 2060 through the strategic implementation of these incentive policies. The 45Q tax credit demonstrates its effectiveness in promoting early-stage research and development (R&D) and demonstration of CCS, while the ETS policy facilitates the commercial development of CCS in the later stage of development. By 2060, the implementation of CCS incentive policies could potentially result in 7.7 ∼ 17.4 % reduction in China's primary energy consumption, 71.2 ∼ 82.7 % decrease in the carbon price of ETS and 5.64 ∼ 6.59 % increase in the GDP compared with the no-policy scenario. In addition, the sectoral output in various sectors and the welfare of urban and rural households also increase. This paper provides an important reference for the realization of China's carbon neutrality goal and the model framework can be applied to other countries. [ABSTRACT FROM AUTHOR]

Soil-based carbon farming has been identified in previous research as a win-win for farm productivity and the mitigation of climate change through carbon sequestration. However, it faces numerous barriers to adoption, including low carbon prices, high transaction costs, information barriers and high uncertainty around future outcomes, markets and policy conditions. Collaboration between landholders and other stakeholders has been proposed as a potential means of overcoming some of these barriers, while maximising the benefits of soil-based carbon farming. In this article, we present the results of a two-stage process investigating collaborative soil-based carbon farming in Australia, involving national-scale key informant interviews and a regional-scale Participatory Rural Appraisal. Fifty-three interviews were undertaken with key carbon farming stakeholders, including landholders, landholder groups, carbon service providers, government, researchers and the financial sector. Collaboration was seen to offer the greatest advantages in relation to knowledge-sharing and social support, followed by its potential to increase carbon income through enhanced bargaining power and the optimisation of co-benefits. The advantages of collaboration were less clear in relation to reducing costs or maximising farm productivity and collaboration also presents new challenges around risk and complexity. Under current conditions, informal collaboration models were seen to offer the best balance between the benefits and risks, with existing cooperatives also well-placed to diversify into carbon. Alternative conditions in the future or in other locations would be needed to facilitate models involving joint projects, pooled credits, shared land management and/or the creation of new carbon-specific cooperatives. • Soil-based carbon farming benefits both carbon sequestration and farm productivity. • Advantages of collaboration are greatest for knowledge-sharing and social support. • Collaboration less beneficial in relation to cost-reduction and farm productivity. • Informal models for collaboration preferred by study participants. • Existing agricultural cooperatives are well-placed to diversify into carbon farming. [ABSTRACT FROM AUTHOR]

Fire and overgrazing reduce aboveground biomass, leading to land degradation and potential impacts on soil organic carbon (SOC) and total nitrogen (TN) dynamics. However, empirical data are lacking on how prescribed burning and livestock exclusion impact SOC in the long-term. Here we analyse the effects of 19 years of prescribed annual burning and livestock exclusion on tree density, SOC and TN concentrations in the Sudanian savanna ecoregion at two sites (Tiogo and Laba) in Burkina Faso. Results revealed that neither livestock exclusion nor prescribed burning had significant impact on SOC and TN concentrations. The results at both sites indicate that 19 years of livestock and fire exclusion did not result in a significant increase in tree density compared to grazing and annual prescribed burning. The overall mean (± SEM) of SOC stocks in the 0–50 cm depth increment in the unburnt (53.5 ± 4.7 Mg C ha−1) and annually burnt (56.4 ± 4.3 Mg C ha−1) plots at Tiogo were not statistically different. Similarly, at Laba there was no significant difference between the corresponding figures in the unburnt (37.9 ± 2.6 Mg ha−1) and in the annually burnt plots (38.6 ± 1.9 Mg ha−1). Increases in belowground inputs from root turnover may have countered changes in aboveground biomass, resulting in no net change in SOC and TN. We conclude that, contrary to our expectation and current policy recommendations, restricting burning or grazing did not result in increase in SOC stocks in this dry savanna ecosystem. [ABSTRACT FROM AUTHOR]

• Climate change threatens the carbon sink capacity of forests in Chile. • Industrial plantations do not contribute towards achieving carbon neutrality. • Wildfire emissions exceed the nationally determined contributions mitigation. • Climate actions should diversify including a wider range of nature based solutions. • Conservation and restauration of wetlands can contribute to carbon neutrality. As president of the Climate Change Conference of the Parties, Chile has advocated for developing ambitious commitments to mitigate greenhouse gas emissions to achieve carbon-neutrality by 2050. However, Chile's motivations and ambitious push to reach carbon-neutrality are complicated by a backdrop of severe drought, climate change impacts (i.e., wildfires, tree mortality), and the use of industrial plantations as a mitigation strategy. This has become more evident as widespread and severe wildfires have impacted large areas of industrial plantations, transforming the land-use, land-use change, and forestry sector from a carbon sink to a net carbon source. Consequently, Chile must diversify its climate actions to achieve carbon-neutrality. Nature-based solutions, including wetlands-peatlands and oceans, represent alternative climate actions that can be implemented to tackle greenhouse gas emissions at a national level. Diversification, however, must guarantee Chile's long-term carbon sequestration capacity without compromising the ecological functionality of biodiverse tree-less habitats and native forest ecosystems. [ABSTRACT FROM AUTHOR]

Over millions of years, the interaction of marine basalt with percolating seawater in low-temperature ocean floor hydrothermal systems leads to the formation of calcite and aragonite. The presence of these minerals in marine basalts provides evidence for substantial CO 2 fixation in these rocks. Here, we report on laboratory experiments to study this process under enhanced CO 2 partial pressures (p CO 2) at 130 °C. Mid-ocean-ridge-basalt (MORB) glass was reacted with North Atlantic Seawater charged with CO 2 in batch experiments lasting up to 7 months. For experiments initiated with seawater charged with ~2.5 bar p CO 2 , calcite and aragonite are the first carbonate minerals to form, later followed by only aragonite (±siderite and ankerite). For experiments initiated with seawater charged with ~16 bar p CO 2 , magnesite was the only carbonate mineral observed to form. In total, approximately 20% of the initial CO 2 in the reactors was mineralized within five months. This carbonation rate is similar to corresponding rates observed in freshwater-basalt-CO 2 interaction experiments and during field experiments of the carbonation of basalts in response to CO 2 -charged freshwater injections in SW-Iceland. Our experiments thus suggest that CO 2 -charged seawater injected into submarine basalts will lead to rapid CO 2 mineralization. Notably, at p CO 2 of tens of bars, magnesite will form, limiting the formation of Mg-rich clays, which might otherwise compete for the Mg cation and pore-space in the submarine basaltic crust. This suggests that the injection of CO 2 -charged seawater into subsurface basalts can be an efficient and effective approach to the long-term safe mineral storage of anthropogenic carbon. [ABSTRACT FROM AUTHOR]