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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]

• 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]

• 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]

• UCCS research, initiated in the 1990s, is following a sigmoidal growth pattern. • No highly active research group has been identified in UCCS research. • USA and China are currently leading countries in UCCS research. • More systematic studies are required to promote UCCS for real applications. • Findings can be used by stakeholders such as governments, among others. In this study, a scientometric comprehensive analysis has been executed in order to explore the scientific situation of research efforts performed previously with regard underground CO 2 sequestration and encapsulation. To this end, a total of 1280 bibliographic records from the Web of Science (WoS) database were extracted and analysed to report the analysis of scientific state of the authors, journals, countries, and categories. Eventually, geospatial maps of the progress in this field are created and presented. As per the results obtained, efforts on this subject have been initiated significantly since 1990s. Scientific articles and proceeding papers share nearly 63% and 31% of the documents published. The results indicate that USA and China are the most contributing countries. Among the active journals, international journal of greenhouse gas control impact is the most active journal. It may be concluded that no highly active research group has yet been emerged. Hence, more supports and scientific efforts are needed to promote carbon dioxide capture and storage technologies. [ABSTRACT FROM AUTHOR]

Whilst carbon capture and storage (CCS) has been promoted as a direct countermeasure against global warming, there remains much debate about what its final role as a climate change mitigation strategy will be. One key criticism directed towards CCS has been its inability to gain public support. This study compares public attitudes to the range of low carbon energy sources and technologies across Australia and China, and is the first study to compare primary data across these two countries on this topic. An online survey encompassing a broad set of questions was used to identify the factors that are associated with support for CCS compared to other energy technologies. Data were collected from a nationally representative Australian sample (n = 2383) and from Chinese urban residents across six regions (n = 1266). The survey confirmed low levels of knowledge and support for CCS in both countries. However, male respondents, those who perceived themselves to have higher knowledge of CCS, and those who valued economic outcomes over environmental protection were more likely to support CCS - as long as the risks were not perceived to outweigh the benefits. The results found that for Australians who believed in human-induced climate change they were likely to be unsupportive of CCS. This opposition appears to be linked to no tolerance for extending fossil fuels as in our factor analysis CCS was aligned to fossil fuels in Australia. In both countries, support for renewable energy technologies remains strong. Given the International Energy Agency's future energy demand projections, combined with slow progress towards meeting the Paris Climate Agreement, the lack of knowledge and support for CCS is concerning. While there have been some technological advances, without parallel improvements in public acceptance of CCS, it will be difficult to see any commercial projects going forward in the near future. Although, the Chinese government's success in educating on climate science, as evidenced in these results, suggests that they may be more effective at informing the public of the benefits of CCS and take the lead on its deployment for climate change mitigation. Based on the latest climate models, it is almost crunch time for governments to decide if CCS has a role to play as part of an energy transition to a low carbon future or perhaps it may be time to turn their focus to climate adaptation. [ABSTRACT FROM AUTHOR]

Coastal salt marshes suffering from anthropogenic coastal development and sea level rise have attracted much attention because of their capacity for carbon sequestration and global climate change mitigation. Accurate mapping of coastal salt marshes is always the first step for their protection, management, and restoration. The inherent complexities of vegetation, dynamics of tides, and anthropogenic disturbances pose challenges for remote sensing-based approaches. Existing studies have utilized phenology information and various black-box algorithms to reduce misclassifications. However, the approaches with dual-temporal images containing phenology information have suffered from inefficiency; the misclassifications have been objectively post-processed rather than considered in the method design, and the tacit knowledge of the trained black-box models has not been revealed. To address the above issues, we proposed a new approach with solid improvements in dual-temporal image construction, misclassification processing, and tacit knowledge analysis, including an efficient method to synthesize dual-temporal images based on the common divisor of the green-up season or senescence season resulting from latitudinal gradients in narrow coastal areas of China, a detailed classification scheme by interpretation of iteratively collected samples, and a key decision rule approximating the trained model. We applied the approach to Sentinel-1/2 images and DEM data, thus deriving a 10-m resolution coastal salt marsh map of China with an overall accuracy of 92.5%. A qualitative comparison showed that the map produced in this study was fitted well with actual salt marsh distributions, resulting in improved accuracy when compared to recently generated maps. The most important contribution is that the overall nature of the trained model observed from the training samples was approximated by a four-feature decision rule following the principle of explainable artificial intelligence, i.e., B8 senescence /B4 senescence < 2.06 & B4 green /B8 green < 0.78 & B12 green /B11 green < 0.72 & elevation < 2.13 , and thus established a new potential classification mechanism for dual-temporal black-box algorithms, i.e., the water signal was covered up by flourishing vegetation, but the situation changed when vegetation withered. This study not only generates an accurate coastal salt marsh map at a national scale but also provides a classification mechanism for dual-temporal image-based coastal salt marsh identification and mapping. • Developed an efficient method for constructing senescence and green images. • Established a mechanism for dual-temporal image-based coastal salt marsh mapping. • Provided a coastal salt marsh map with solid improvements on the most recent one. • Explored a case of explainable artificial intelligence (XAI) in the coastal. [ABSTRACT FROM AUTHOR]

• Revealing superliner link between CFP and population density in the lower CFP cities. • Population clustering may mitigate CFP in the higher CFP cities. • Presenting policy implication of differentiated population density regulation. The growing imbalance between anthropogenic carbon emissions and vegetation carbon sequestration is impeding cities' sustainability. However, previous research has not reached a consensus on whether population density regulation can mitigate this growing imbalance. In this study, we first used the carbon footprint pressure (CFP) indicator to examine the temporal and spatial characteristics of the imbalance in 370 Chinese cities over the last 20 years. Second, we demonstrated the favorable but limited effect of existing technology on CFP mitigation using the IPAT equation, the Logarithmic Mean Divisia Index decomposition approach, and the Kaya identity. Further, we emphasized the dominant effect of the population on CFP in urban agglomerations and provincial capital cities through Maxwell's triangle. Finally, using a built panel data model, we identified an inverted U-curve relationship between CFP and population density at the middle and low quartiles, whereas population clustering promoted CFP mitigation at the upper quartiles. Given the limited effectiveness of current climate actions, as well as the coexistence of urban diseases and unoccupied buildings, we provided differentiated policy implications in city-scale for population density regulation. This study provides some inspiration for authorities to formulate city-scale population policies to mitigate climate change and achieve sustainable development. [ABSTRACT FROM AUTHOR]

Although post-combustion carbon capture (PCC) has been regarded as a near-commercial technology, the scale-up development of PCC the technology remains hindered by its severe thermodynamic and economic penalties. As a consequence, the solar-assisted carbon capture and storage (CCS) technology is emerging recently, which poses a promising possibility to offset the power generation loss caused by the intensive energy consumption from PCC process. Nevertheless, the application potential of the solar-assisted CCS technology would highly depend on its realistic greenhouse gas (GHG) mitigation benefit as well as its cost relative to alternative low carbon technologies. Thus, it is required to apply an improved assessment practice to recognize solutions for such sustainable power supply chains, considering an increasing threatening from climate change. In this study, solar-assisted post-combustion CCS processes are analyzed trough a life cycle approach, combing life cycle GHG assessment and life cycle cost analysis. A typical 300MWe coal-fired power plant in China is taken as the case study. Three scenarios are further analyzed: (1) base case integrated with CCS process; (2) base case integrated with CCS and solar-assisted reboiler heating process; (3) base case extended to CCS and solar-assisted repowering process. Results show that the solar-assisted repowering case has considerable advantage in both GHG mitigation potential and cost aspect with superior life cycle GHG reduction rate and life cycle cost of energy removed (LCOR) at 73.7% and 37.2$/ t c o 2 − e q respectively. While the solar-assisted reboiler heating case does not have evident competition superiority. It is further highlighted that the GHG emissions from the upstream and transportation stages are also critical for Chinese CCS chains. [ABSTRACT FROM AUTHOR]

Carbon capture, utilization, and storage (CCUS) is a crucial technology for global climate mitigation. To implement large-scale CCUS, decisions about where and how to build a CO 2 transportation network are urgently required. However, previous studies are limited in proposing the economical transportation network for CCUS that considered comprehensive risks from socio-economic, geographical and geological factors. Here, we develop a pipeline layout planning model to investigate the cost-effective and reliable transportation network for CCUS. Results show that to meet the annual CO 2 emission reduction target of 654 million tons for CCUS in the coal-fired power sector under China's carbon neutral goal, pipelines with a total length of 17,589 km need to be constructed. The emission sources can be transported in pipelines with an average radius of 58 km, and with diameters of 8, 12, and 16 inches. Northeast, north, and northwest China are the main areas suitable for pipeline construction. • Northeast, North, and Northwest in China are vital areas for capture, transport, and storage. • Five large-scale pipeline network groups can be constructed in China. • Pipeline construction is greatly affected by a variety of practical factors. [ABSTRACT FROM AUTHOR]

Using the DeNitrification-DeComposition (DNDC, version 9.5) model, we investigated the soil organic carbon (SOC) changes from 1980 to 2009 in Eastern China's upland-crop fields in northern Jiangsu Province. A currently most detailed high-resolution soil database, containing 17,024 polygons at a scale of 1:50,000, derived from 983 unique upland soil profiles, was used. A coarser county-level soil database was also used for a pair-wise simulation for comparison. We found that SOC changes modeled with the county-level soil database differ significantly from those with high-resolution soil data, with the deviation ranging from −64% to 8.0% in different counties. This implies that coarse soil data may lead to large biases in SOC simulation. With the high-resolution database, the model estimates a SOC increase of 37.89 Tg C in the top soils (0–50 cm) over the study area of 3.93 Mha for the past three decades, with an average rate of 322 kg C ha −1 year −1 . The SOC accumulation in the study region accounts for 10.2% of annual national carbon sequestration of upland soils, compared with the fraction of 3.7% in the total upland area of China. This underscores its significance to national climate mitigation. The annual SOC change varied between 61 to 519 kg C ha −1 year −1 , mainly driven by the variations in N-fertilizer and manure applications. This study highlights the significance of high-resolution soil databases in quantifying SOC changes. Our high-resolution estimates of SOC will support farming and carbon management in this region. [ABSTRACT FROM AUTHOR]

• CO 2 sequestration and EGR are experimentally evaluated in two shale gas reservoirs. • Pore heterogeneity and connectivity are evaluated via multifractal analysis. • Shale composition controls on gas storage is evaluated from gas adsorption measurements. • Links between MICP and gas adsorption measurements were used to evaluate EGR suitability. In the global effort toward climate change mitigation, geologic storage of CO 2 in shale plays is becoming critical while it can improve production from these reservoirs. In this study, the gas storage capacity and CO 2 sequestration suitability of the Longmaxi and Niutitang shale gas reservoirs is investigated and compared via XRD analysis, programmed pyrolysis, low pressure N 2 and CO 2 adsorption, high pressure CH 4 adsorption, and MICP analysis. Results showed that clay and TOC controls on micropore heterogeneity and connectivity happens only within the Longmaxi Formation. Furthermore, both components play a role in the adsorbed quantities of gas in the formation which revealing a higher storage capacity in mesopore-macropores. This was verified by a positive correlation between adsorbed volume within the mesopore-macropore space. The Longmaxi Formation was also found to own better pore connectivity and PSD homogeneity of mesopore-macropores, indicating easier pathways for CO 2 movement channels within the pore network. Furthermore, the samples from the Longmaxi exhibited a positive relationship between adsorbed volume with the CO 2 breakthrough pressure and median pore diameter, alike between the mesopore-macropore volume and CO 2 breakthrough pressure. This means, the injected CO 2 will displace adsorbed methane within the mesopore-macropore and will be adsorbed and stored in such pores. Overall, superiority of the Longmaxi shale over the Niutitang for CO 2 storage and EGR would be significant for future operations in similar shale gas reservoirs in China and around the globe. [ABSTRACT FROM AUTHOR]

• We construct a multi-model comparison framework by employing typical IAMs. • We examine how China will contribute to the global 1.5 °C climate target. • China could contribute nearly one-fifth of the global negative emissions by 2100. • The proportion of BECCS could dramatically increase to 29% under the 1.5 °C case. • Energy demand control may rely more on coordination between CCS and clean energy. Enhancing the warm-limiting targets to from below 2 °C to 1.5 °C is of great significance for climate change mitigation, during which the carbon capture and storage (CCS) of China is playing an important role. By framing a multi-model analysis to compare IAMs, this study aims to explore how China can contribute to the global 1.5 °C target, consistent with achieving its carbon neutrality goal. Our multi-model assessment shows that the enhanced targets will advance the reach time of China's carbon peak and neutrality. Under a relatively smooth emission path curve with CCS, China's carbon emissions will decrease sharply by the end of this century. It is estimated that China's negative carbon emissions will contribute nearly one-fifth of the global negative emissions in 2100, with its CCS-captured emissions accounting for 14%. In the energy system, fossil- and biomass-CCS will develop rapidly, with the proportion of biomass with CCS dramatically increasing to 29% and 17% under the 1.5 °C and 2 °C scenarios, respectively. There will be a relatively large gap between the capital and final use costs of CCS, which may weaken the technical advantage when competing with renewables during the life cycle. While the overall control of the energy consumption in the later period will rely more on the proportional adjustment and the coordination between biomass with CCS and clean energy. [ABSTRACT FROM AUTHOR]

The carbon balance in urban areas has become a major research challenge and a principal policy concern in efforts to address anthropogenic climate change. Rapid urbanization and industrialization in China urge the search for integrated strategies to mitigate and adapt to climate change, which not only limit to traditional infrastructure sectors, but also cover urban green infrastructure, because plants and soils function as carbon sinks through biotic sequestration. This study presents a nationwide study about how urban green infrastructure could contribute to the carbon balance in 35 major Chinese cities. By the end of 2010, the total area of urban green spaces (the dominant components of urban green infrastructure) accounts for 6.38% of the total land area of these cities and represented 51.7% of the total urban green spaces of all 657 cities in China. Based on empirical data from the literature, the total amount of carbon stored in the vegetation of the urban green infrastructure of 35 cities was estimated at 18.7 million tons, with an average carbon density of 21.34 t/ha. In 2010, the amount of carbon sequestration totaled 1.90 million tons with an average carbon sequestration rate of 2.16 t/ha/year. Collectively, only 0.33% of the carbon emissions from fossil fuel combustion can be offset, ranging from 0.01% in Hohhot to 22.45% in Haikou. Nevertheless, the dominance of young vegetation stands in Chinese urban green infrastructure suggests this small carbon sequestration efficiency could become substantial in the near future, given that appropriate policies and management practices are adopted to promote urban green infrastructure for climate change mitigation and adaptation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A bi-level joint-probabilistic programming approach is developed. • It can handle leader–follower issues and joint-probabilistic constraints. • The proposed approach is applied to China's multi-regional energy system model. • The optimal schemes during 2021–2050 under three mitigation scenarios are obtained. • Results are helpful to achieve low-carbon goals in multi-regional energy system. Climate change mitigation and renewable resources utilization are becoming particularly urgent for energy system management. In this study, a bi-level joint-probabilistic programming (BJPP) method is developed for planning multi-regional energy system under different mitigation policies and uncertainties. BJPP can handle leader–follower issues in decision-making process as well as examine the risk of violating joint-probabilistic constraints. Based on the BJPP method, a China's multi-regional energy system (named as BJPP_CMES) model is formulated to provide optimal scheme for energy system planning of China over a long-term horizon (2021–2050) by synergistically minimizing carbon dioxide (CO 2) emission and system cost. A series of scenarios associated with different carbon capture and storage (CCS) levels and violation risks of energy-demand constraints are examined. Results reveal that: (i) the share of non-fossil energy in China's energy supply would keep increasing in 2021–2050, and the highest growth of the renewable supply would occur in Ningxia (rising 47.7%); (ii) Sichuan, Inner Mongolia, and Gansu would be the top three suppliers of renewable electricity; (iii) the CO 2 emission of China would reach a peak of [44.3, 54.8] billion tonnes during the period of 2026–2030; Shandong, Inner Mongolia, and Shanxi would be main contributors of CO 2 emission in the future; (iv) compared with the single-level model, the CO 2 emission from the BJPP_CMES model would reduce by [2.7, 5.7]%; (v) among developed regions, the individual probability level of Jiangsu-Zhejiang-Shanghai is the most significant parameter for both CO 2 emission and system cost. The findings are helpful for decision makers to optimize multi-regional energy system (MES) with a low-carbon and cost-effective manner, as well as to provide useful information for renewable energy utilization and regional sustainable development. [ABSTRACT FROM AUTHOR]

Abstract: Mixed-tree plantations can be a good silvicultural alternative to large-scale monoculture coniferous plantations for climate change mitigation, which is facilitated by the sequestration of atmospheric carbon dioxide. To evaluate the impacts of tree species compositions on the carbon storage capacity of plantation ecosystems, we measured the above and belowground biomass, as well as the carbon content, in three 27-year old forest plantations of monoculture Castanopsis hystrix (CH stand), monoculture Pinus massoniana (PM stand), and mixed C. hystrix and P. massoniana (mixed CH/PM stand) stands. We developed an allometric equation to estimate tree carbon storage. The carbon storage levels of understory, litter, and soil components were also estimated. Results show that biomass is positively correlated with carbon storage. The ecosystem carbon storage of the mixed CH/PM stand (327.03Mgha−1) was higher than those of the CH (314.59Mgha−1) and PM (293.60Mgha−1) stands. The majority of carbon storage was found in the soil pool (84.73%, 63.54%, and 75.80% in the CH, PM and mixed CH/PM stands, respectively). Almost 40% of soil carbon at a depth of 0–60cm was stored in the upper 20cm of the soil pool. Except for the vegetation layer, each layer of the CH and mixed CH/PM stands consisted of a higher amount of carbon than did the layers of the PM stand. These findings suggest that mixed CH/PM plantation stands or valuable indigenous CH plantation stands more substantially improve carbon storage in litter, soil, and ecosystems than do monoculture PM plantation stands. The results also imply that developing valuable indigenous tree species is a good silvicultural option for enhancing carbon sequestration and valuable timber cultivation in subtropical China. [Copyright &y& Elsevier]

Abstract: Soil C sequestration in cropland could play an important role in mitigating the rapidly increasing CO2 emissions in China. Many efforts had been dedicated to estimating the potential for C sequestration in croplands. Potential increases in SOC in China''s croplands had been recently evaluated using inventory-up-scaling simulation and crop-soil C process-based modeling. In this study, data of SOC change at monitoring sites from croplands across mainland China were collected from publications available from 1985 to 2006 to perform a statistical analysis. The data set comprises 1081 observations (404 from rice paddies, RPs and 677 from dry croplands, DCs). Frequency analysis indicates that over 70% of observations show an increase in SOC, which is higher among RPs than DCs. To quantify SOC dynamics, a Relative Annual Change Index in gkg−1 year−1 (RAC, gkg−1 year−1) is defined and calculated using the initial and final SOC values for the duration of monitored observations. RAC values ranged from −0.806 to 0.963gkg−1 year−1 for DCs and from −0.597 to 0.959gkg−1 year−1 for RPs, respectively. From this data, the average is estimated to be 0.056±0.200gkg−1 year−1 for DCs, and 0.110±0.244gkg−1 year−1 for RPs, with an overall estimate for China''s croplands, with RPs and DCs combined, of 0.076±0.219gkg−1 year−1. A mean increase in topsoil C (0–20cm) stock of China''s croplands was estimated to be 25.5TgCyear−1 (8TgCyear−1 in RPs and 17.5TgCyear−1 in DCs) between 1985 and 2006, with a total topsoil C stock increase of 0.64 Pg C over the whole period. The annual stock increase may offset ∼20%, on average, of the total CO2 emissions of China for 1994. This study suggests an important role of China''s croplands, especially rice paddies, for C sequestration to mitigate climate change. [Copyright &y& Elsevier]

• An integrated top-down and bottom-up modeling framework was developed. • Analyze low-carbon pathways for Chinese iron & steel industry towards carbon neutrality. • Both the supply-side and demand-side contributions to decarbonization are explored. • Energy-saving retrofitting technologies help short-term CO 2 emissions reduction. • Breakthrough technologies are crucial in achieving carbon neutrality. Iron and steel production in China contributes to 14% of China's total energy-related CO 2 emissions. Decarbonizing the iron and steel sector will therefore play an important role in achieving the goal of carbon neutrality. This study explored possible low-carbon transition pathways for China's iron and steel industry to achieve carbon neutrality by 2050. An integrated approach was developed that combined a computable general equilibrium model and a bottom-up technology-selection module. The results indicated that although energy-saving technologies can reduce CO 2 emissions in the short term, in the long term, adopting breakthrough technologies (e.g., carbon capture and storage (CCS) and hydrogen-based direct reduction (DR)), increasing the share of scrap-based electric arc furnace (EAF) steel production, and decarbonizing upstream energy-supply sectors will be crucial for climate change mitigation. Hydrogen-based DR could be an effective option for CO 2 emission reduction in scenarios where CCS is not available, with its share increasing to 23%–25% by 2050. System-wide cross-sector decarbonization can help achieve climate targets at lower costs through flexible technology combinations and avoid carbon leakage into upstream energy-supply sectors. [ABSTRACT FROM AUTHOR]

Carbon Capture, Utilization and Storage (CCUS) is considered a critical carbon dioxide reduction technology for climate change mitigation. More recently, it has been attracting significant attention from the Chinese government, industry and academia in relation to its research, development and deployment. This paper screens 1,202 unique scientific articles from Web of Science related to China's CCUS and employs Citespace to conduct a knowledge mapping of the domain. The results show that the number of publications have increased and CCUS has become a multidisciplinary area of study. The paper visually demonstrates the most productive institutions, main authors, and primary sources of China's CCUS research domain. Moreover, the paper explains how the research topics have changed over time and discovers the current research frontiers including "pipeline", "shale gas" and "steel". Of significant interest is the finding that China's CCUS research progress appears to be directly related to the increasing policy support through China's five-year planning process. However, research regarding public perception, financial mechanisms and appropriate business models for CCUS deployment is found to be less prevalent. Recommendations to improve research in these areas are provided from the perspective of government intervention. This paper also highlights the importance of continued government support for CCUS as part of the national development strategy for carbon emissions reduction and transitioning towards a low carbon future. • The evolution of China's CCUS research is identified using a bibliometric method. • Outlines research foci, most productive organizations, main authors and top-tier journals. • Government intervention appears the most significant driver for CCUS development in China. • Three research areas−"pipeline", "shale gas" and "steel"− are receiving strongest policy support. • The topics "public perception", "financial mechanisms", and "business models"− lack sufficient focus in China. [ABSTRACT FROM AUTHOR]

As bioenergy produces neutral or even negative carbon emissions, the assessment of biomass resources and associated emissions mitigation is a key step toward a low carbon future. However, relevant comprehensive estimates lack in China. Here, we measure the energy potential of China's domestic biomass resources (including crop residues, forest residues, animal manure, municipal solid waste and sewage sludge) from 2000 to 2016 and draw the spatial-temporal variation trajectories at provincial resolution. Scenario analysis and life cycle assessment are also applied to discuss the greenhouse gas mitigation potentials. Results show that the collectable potential of domestic biomass resources increased from 18.31 EJ in 2000 to 22.67 EJ in 2016 with overall uncertainties fluctuating between (−26.6%, 39.7%) and (−27.6%, 39.5%). Taking energy crops into account, the total potential in 2016 (32.69 EJ) was equivalent to 27.6% of China's energy consumption. If this potential can be realized in a planned way to displace fossil fuels during the period 2020–2050, cumulative greenhouse gas emissions mitigation would be in the range of 1652.73–5859.56 Mt CO 2 -equivalent, in which the negative greenhouse gas emissions due to the introduction of bioenergy with carbon capture and storage would account for 923.78–1344.13 Mt CO 2 -equivalent. Contrary to increasing bioenergy potentials in most provinces, there are declining trends in Tibet, Beijing, Shanghai and Zhejiang. In addition, Yunnan, Sichuan and Inner Mongolia would have the highest associated greenhouse gas mitigation potentials. This study can provide valuable guidance on the exploitation of China's untapped biomass resources for the mitigation of global climate change. • China's bioenergy potential in 2016 accounted for 27.6% of its energy consumption. • The bioenergy potential in Tibet, Beijing, Shanghai and Zhejiang was declining. • GHG mitigation potentials of China's bioenergy would be 1653–5860 Mt CO 2 e by 2050. • China's bioenergy can contribute 6–21% to a global carbon mitigation goal in 2050. [ABSTRACT FROM AUTHOR]

Petroleum refining is a technology complex, energy- and CO 2 emission-intensive industrial process, which is affected by the type and property of the crude oil. China has been the exploitation of crude oil to paraffinic most. This paper targets to quantify and evaluate the material or energy metabolism and environment loads of paraffin-based petroleum at refining process unit-level through the established petroleum flow and energy flow on the CO 2 emissions accounting framework, and explores energy conservation and CO 2 emission reduction pathways and policy implications, using a typical paraffin-based petroleum refining enterprise in China as a case. The results indicated that the crude oil from the inputs were fractionated in the atmospheric and vacuum distillation (AVD) unit, and its energy consumption and CO 2 emissions accounted for 14.38% and 13.2% of the total energy consumption and CO 2 emissions in the case study, respectively. With the transformation of petroleum refinery plant structure, fluid catalytic cracking (FCC), ketone benzol dewaxing (KBD), and delayed coking units dominated more energy consumption and CO 2 emissions. FCC unit was both the largest energy consumer and supplier, flue gas waste heat recovery efficiency of which was an important factor affecting energy conservation and CO 2 emission reduction for FCC unit and even enterprise. KBD unit records the largest energy and CO 2 emission intensities, which are 67.95 kgce/t product and 256.82 kgCO 2e /t product respectively, due to the high wax content of paraffin-based crude oil and the coal-dominated power generation structure. Based on these research findings, three mitigation policy recommendations were proposed, including the improvement of energy efficiency, optimization of energy consumption structure and product output structure. Carbon capture and storage can reduce CO 2 emission by about a third in the concentrated units of primary energy consumption (i.e. AVD, FCC, and DC). The results of this paper are key components of the life cycle assessment of the CO 2 emissions of petroleum fuels produced by domestic paraffin-based crude oil. [ABSTRACT FROM AUTHOR]

Coal-fired power plays an important role in China's power supply, even though the photovoltaic (PV) power has developed rapidly in recent years. Carbon capture and storage (CCS) technology is essential for achieving anticipated long-term climate change mitigation targets. However, China's government subsidy policies tend to support PV, while incentives for CCS are few. Given this situation, a trinomial tree modeling-based real options approach was developed to evaluate CCS retrofitting investment in coal-fired power plants versus PV power investment. This model includes setting different policy scenarios by considering electricity tariff subsidies and Chinese emission trading scheme (CN-ETS). The results showed that coal-fired power with CCS has a cost advantage over PV power in most provinces in China, if the electricity tariff and other subsidy policies remain the same; however, PV power will be cheaper than coal-fired power with CCS in Yunnan, Tianjin, Hebei, Shanghai and Shanxi provinces in the above cases. Incorporating CCS into CN-ETS could cut the former's application cost, but the incentive effect of CN-ETS is not obvious, because the carbon price in China is currently too cheap, and the incentive effect of a power tariff subsidy (subsidy at the PV power tariff level) is much better for PV than for CN-ETS. Increasing the load factor is an important way to reduce the CCS application cost for power plants. The results of this study provide reference and guidance for the collaborative development of CCS and PV. • Trinomial tree model was used to evaluate CCS and PV investment. • CCS and PV investment were compared in different provinces in China. • Regional factors and policy factors were taken into account. • Suggestions on CCS and PV development in China were put forward. [ABSTRACT FROM AUTHOR]