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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]

• 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]

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]

• 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]

• Substitution factors for forest products for the Canadian context were developed. • Substitution factors ranging from 0.51 to 0.91 tC/tC were found. • They will lead to more accurate assessments of the forest GHG mitigation potential. • These factors will help governments to manage forest and fight climate change. Evaluating the climate change mitigation potential of the forest sector requires a holistic approach based on forest carbon (C) sequestration, C storage in harvested wood products (HWP) and substitution on markets. High uncertainty is associated with substitution factors, that express avoided fossil greenhouse gas (GHG) emissions from the use of forest-based products in replacement of GHG-intensive materials and fossil fuels. Few studies have focused on the development of substitution factors in Canada, resulting in the use of unrepresentative generic data. Here, we provide a framework to reduce uncertainties related to substitution factors for primary wood products in a Canadian context. A life cycle assessment framework is used to quantify fossil GHG emissions for a baseline and a wood-intensive scenario. For solid product substitution, we focused on the construction sector and analyzed a range of innovative wood buildings with steel and reinforced concrete as alternative materials. We found non-weighted averages of 0.80 tC/tC for sawnwood and 0.81 tC/tC for panels. For energy substitution, we analyzed cases with different specifications on biomass product, facility type and alternative fossil fuel source in non-residential heat production and biofuel transportation sectors. We found a non-weighted average of 0.80 tC/tC for non-residential heat production and 0.51 tC/tC for biofuel transportation, that can be interpreted as 0.91 tC/tC for heavy fuel oil, 0.69 tC/tC for light fuel oil and 0.68 tC/tC for natural gas substitution. These results provide a benchmark for substitution factors in Canada, to help guide forest management strategies for climate change mitigation. [ABSTRACT FROM AUTHOR]

In the face of escalating global climate challenges, effective carbon dioxide (CO₂) capture techniques remain at the forefront of mitigating anthropogenic greenhouse gas emissions. This comprehensive review elucidates the latest advancements in CO₂ capture, emphasizing two predominant methodologies: absorption and adsorption. We delve into the mechanisms underlying each process, highlighting the novel materials and technologies that have emerged over recent years. For absorption, the focus is placed on the material design strategy, and identifying new materials in the class of amines, ionic liquids (ILs) and nanofluids for enhanced CO 2 capture capacities and reduced energy requirements. In the realm of adsorption, the synthesis of innovative adsorbents, such as metal organic framework (MOF), organic polymers, inorganic adsorbents, silicon-based adsorbents, and biochar and byproducts from biomass with superior selectivity and stability, is explored. Additionally, the review addresses the challenges associated with each method, offering insights into potential avenues for further research. By providing a holistic overview of the current landscape of CO₂ capture, this article serves as a pivotal resource for researchers and industry professionals aiming to advance sustainable solutions to combat climate change. [Display omitted] • Absorption and adsorption materials are at the forefront of CO 2 capture technologies. • Ionic-liquids and nanofluids can be comparable to amines with improvements in scalability and stability. • Biomass byproducts as adsorbents offers a sustainable solution to CO 2 capture. [ABSTRACT FROM AUTHOR]

Despite numerous prior studies regarding public acceptance of climate change mitigation technologies, most academic papers focus on individual technologies in their analyses. Little is known about the acceptance of multiple low-carbon energy technologies. This study bridges this research gap and explores the cross-technology acceptance of various energy solutions at different locations. Thus, we provide a comprehensive understanding of public acceptance patterns by analysing a broader range of technologies concurrently, focusing on: (a) nuclear power, (b) district heating, (c) energy-saving technologies, (d) onshore, nearshore, and offshore wind power (WP), (e) photovoltaics (PV) installed on agricultural land, industrial roofs, and private roofs, and (f) carbon capture and storage (CCS) in offshore, nearshore, rural onshore, and urban onshore locations. Based on Danish nationally representative survey data, our results give strong policy indications that PV on industrial rooftops is accepted at the highest level. In contrast, nuclear power, onshore rural and urban CCS, and nearshore CCS are the least accepted technologies to combat climate change among the Danish public. Additionally, we discover that the acceptance of a specific technology is contingent on locations. Specifically, the public acceptance of PV, WP, and CCS depends on the place of living and the potential location of technology placement. Finally, this study explores subgroup analyses to compare acceptance differences according to gender, age, education, income, and location of residence. [Display omitted] [ABSTRACT FROM AUTHOR]

Plants capture atmospheric carbon dioxide (CO 2) for carbon (C) assimilation through photosynthesis, with the photosynthates stored as plant biomass (above- and below-ground plant parts). The C stored as living biomass is a short-term C sequestration strategy, whereas soil organic carbon (SOC) is a long-term C sequestration strategy. In this regard, plant roots are the primary route of C entry into the SOC pool. Through establishing a recalcitrant SOC pool, long-term sequestration can potentially offset the C losses caused by soil degradation in industrial and pre-industrial eras. Over the next 50–100 years, implementing effective agricultural practices could sequester 80–130 GT (109) C as SOC. Carbon, as the primary elemental component of soil organic matter, plays a significant role in shaping the soil's physical, chemical, and biological properties, ultimately influencing soil biomass productivity. By enhancing crop productivity and biomass production, farmers can increase C sequestration, creating a positive feedback loop that contributes to overall C sequestration. Carbon sequestration has numerous co-benefits, including climate change mitigation, ecosystem health, food security, and farm profitability. Adopting conservation agriculture and site-specific practices and developing crop and pasture genotypes with high yields and C sequestration potential should significantly improve crop productivity and C sequestration simultaneously. This opinion article delves into the nexus between photosynthesis and soil C sequestration, highlighting its significance in enhancing farm productivity while mitigating climate change. [Display omitted] • Good agricultural practices could sequester 80–130 GT (109) C as soil organic carbon (SOC). • Engineering of carbon-concentrating mechanisms can enhance carbon assimilation potential of plants. • Afforestation and restoration of degraded lands can improve SOC besides other ecosystem services. [ABSTRACT FROM AUTHOR]