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Bioenergy with carbon capture and storage (BECCS) is one of the key negative emission technologies (NETs). Large-scale implementation of BECCS has been criticized of the associated increase in land use. The existing large Nordic pulp and paper production units enable BECCS deployment without additional land use, as they currently release large amounts of bio-based carbon dioxide (CO2). The application of BECCS in pulp mills has been found technically feasible in earlier studies. This study explores key factors that affect the propensity to invest in BECCS in different types of existing European pulp and paper mills. The results give fresh understanding on the effects of BECCS on the market price of pulp and paper products and the required level of incentives. Based on statistical data, the marginal carbon dioxide credit (€ per ton CO2) to make BECCS profitable was derived. The results show that the required level of credit greatly depends on the mill type and details and that the feasibility of BECCS does not clearly correlate with the economic performance or the measured efficiency of the mill. The most promising mill type, a market kraft pulp mill, would find BECCS profitable with a credit in the range of 62–70 €/tCO2 and a credit of 80 €/tCO2 would decrease pulp production costs by 15 €/tproduct on average if 50% of CO2 emissions was captured. The EU Emission Trading System (ETS) is the main policy instrument to achieve the climate targets related to fossil energy use, but does not yet contemplate bio-based emissions. [ABSTRACT FROM AUTHOR]

In this work, a techno-economic assessment of carbon dioxide capture from limekiln flue gas of a pulp and paper mill (Mill A) and a linerboard mill (Mill B) using a Monoethanolamine (MEA) absorption desorption process was carried out. We coupled the ASPEN Plus simulator with a derivative-free optimization (DFO) tool to identify the optimal configuration for minimizing the total capture cost. The capture costs were calculated using CAPCOST, a modular program for equipment cost estimation, and appropriate coefficients. Eight degrees of freedom, the direct contact cooler stages, the absorber stages, the stripper stages, the solvent lean loading, the solvent weight concentration, the stripper inlet temperature, the flue gas inlet temperature, and the amount of CO2 captured, were selected for process and flowsheet optimization. Additionally, we evaluated the effect of steam integration and Sect. 45Q of the existing federal tax credit for carbon capture and sequestration on CO2 capture costs. The total capture costs per tonne of CO2 were $64.9 for Mill A and $69.7 for Mill B. When steam integration and Sect. 45Q are considered, the costs dropped to − $2.5 and $2.6 for Mill A and Mill B, respectively. The sensitivity of CO2 capture cost to changes in the inlet flue gas flowrate, flue gas CO2 mol%, and the electricity and MEA prices were investigated. The sensitivity analysis results revealed that the capture costs vary from − $5.9 to $5.9 per tonne of CO2 captured. [ABSTRACT FROM AUTHOR]

Carbon dioxide mineral carbonisation is a means to achieve permanent carbon dioxide storage, this paper to solid waste materials as the main raw material to prepare fly ash-based carbon dioxide storage materials. Through the design of carbon dioxide adsorption experimental setup to study the main factors affecting the adsorption capacity of the fly ash-based storage materials, the experimental results show that, the fly ash mass fraction decreased from 90 to 10%, the water-cement ratio increased from 0.4 to 0.8 when the CO2 adsorption of fly ash-based materials increased by 82% and 30%, respectively. The effect of strong alkali on CO2 adsorption capacity was also investigated in this paper, and the results showed that the CO2 adsorption of the fly ash-based material sample with 10 ml NaOH added increased by 197% compared with that of the sample with 5 ml NaOH added, whereas the adsorption amount was reduced by 85% when 25 ml NaOH was added instead, which was attributed to the accelerated hydration process of the material due to the excessive alkalinity that consumed the calcium and magnesium ions in the material, and at the same time the production of hydration products hindered the transport of CO2 within the material, which led to a decrease in CO2 adsorption. [ABSTRACT FROM AUTHOR]

The adverse effects of climate change calls for the rapid transformation of manufacturing processes to decrease the emissions of carbon dioxide. In particular, a lower carbon footprint can be achieved by capturing carbon dioxide at the site of emission. Here we review the use of industrial effluents, waste and residues to capture carbon dioxide. Waste include steelmaking slag, municipal solid waste incinerator ashes, combustion fly ash, black liquor, paper mill waste, mining waste, cement waste, construction and demolition waste, waste from the organic industry, and flue gas desulfurization gypsum waste. Capture capacities range from 2 to 800 kg of carbon dioxide per ton of waste, depending on processes, waste type and conditions. Cement waste and flue gas desulfurization gypsum waste show the highest capture capacity per ton of waste. [ABSTRACT FROM AUTHOR]

Inadequately treated effluents from industry have serious environmental and public health concerns. Even low level discharges create problems through accumulation in water and soil. In the present work, the pollutant accumulating capacity and the general environmental health status of soil which is a repository of treated and untreated effluent discharges and solid waste dumping of a giant pulp and paper mill have been evaluated with respect to some selected physicochemical parameters. The pollutant accumulating capacity of the soil in seven well-defined sites in and around the mill was found with reference to a 'control' site with no history of receiving effluent discharges or solid wastes. The changes in texture, bulk density, water-holding capacity, electrical conductivity, pH, organic carbon, cation exchange capacity, exchangeable sodium, etc. of the soil up to the normal tilled depth were observed in different seasons. In most sites, the soil organic carbon was poorly correlated to the bulk density, water-holding capacity, pH, and clay and sand contents, indicating an unhealthy state of the soil and, correspondingly, nearly exhausted pollutant accumulating capacity. Considerable differences in pH, electrical conductivity, bulk density, and water-holding capacity were observed between the soil receiving effluent discharge and solid waste dumping and the control soil. The soil had accumulated considerable amounts of the exchangeable cations (Ca, Mg, Na, and K). The work has found that industrial activities have worked against the normal behavior of the soil and reduced its capacity to serve as a natural repository of carbon. [ABSTRACT FROM AUTHOR]

Corporate image, European Emission Trading System and Environmental Regulations, encourage pulp industry to reduce carbon dioxide (CO2) emissions. Kraft pulp mills produce CO2 mainly in combustion processes. The largest sources are the recovery boiler, the biomass boiler, and the lime kiln. Due to utilizing mostly biomass-based fuels, the CO2 is largely biogenic. Capture and storage of CO2 (CCS) could offer pulp and paper industry the possibility to act as site for negative CO2 emissions. In addition, captured biogenic CO2 can be used as a raw material for bioproducts. Possibilities for CO2 utilization include tall oil manufacturing, lignin extraction, and production of precipitated calcium carbonate (PCC), depending on local conditions and mill-specific details. In this study, total biomass-based CO2 capture and storage potential (BECCS) and potential to implement capture and utilization of biomass-based CO2 (BECCU) in kraft pulp mills were estimated by analyzing the impacts of the processes on the operation of two modern reference mills, a Nordic softwood kraft pulp mill with integrated paper production and a Southern eucalyptus kraft pulp mill. CO2 capture is energy-intensive, and thus the effects on the energy balances of the mills were estimated. When papermaking is integrated in the mill operations, energy adequacy can be a limiting factor for carbon capture implementation. Global carbon capture potential was estimated based on pulp production data. Kraft pulp mills have notable CO2 capture potential, while the on-site utilization potential using currently available technologies is lower. The future of these processes depends on technology development, desire to reuse CO2, and prospective changes in legislation. [ABSTRACT FROM AUTHOR]

In recent years, much attention has been focused on carbon accounting for harvested wood products in national greenhouse gas inventories. The methods used for national accounting, however, are not suited to corporate or value chain accounting. This is largely due to the practical difficulties that companies face in assembling the historical production data and other information required by national accounting methods. In addition, national accounting methods produce results that are heavily influenced by historical data and past practices. As a result, these methods provide little insight into opportunities for improvement. In this paper, options are considered for corporate and value chain accounting of carbon in forest products in use. One method is identified that avoids many of the difficulties associated with national accounting methods. The method estimates the amount of carbon in products expected to remain in use for at least 100 years and, therefore, the method is called the 100-year method. A review of forest product time-in-use distributions being used in several countries to develop national carbon inventories reveals that many of them were not designed to produce realistic estimates of the amount of product remaining in use for 100 years. U.S. housing data are used to demonstrate, however, that the time-in-use information used to develop the U.S. national inventory can be used in the 100-year method without over estimating 100-year carbon sequestration in U.S. housing. [ABSTRACT FROM AUTHOR]

This study aimed to maximise the amount of CO2 storage by indirect carbonation using paper sludge ash (PSA), which is an alkaline industrial waste. The properties of the following three types of solvents were considered: acids (acetic acid and hydrochloric acid), ammonium salts (ammonium chloride and ammonium acetate) and others (sodium citrate and water). When carbon dioxide was injected into calcium leachates prepared from PSA using acids, carbonation did not occur, and using ammonium salts as solvent, the carbonation efficiency was low. However, after pH swing of the leachates using sodium hydroxide and ammonia solution for acid and ammonium salt solvents, up to 324 kg CO2/(ton PSA) and 175 kg CO2/(ton PSA) were stored, respectively. When carbon dioxide was injected into calcium leachates prepared from PSA using sodium citrate or water, solid was initially generated which later dissolved. In order to solve this problem, CO2 injection was stopped just before the pH of the solution reached 10.5 for sodium citrate and 8.3 for water, resulting in the storage of 136 kg CO2/(ton PSA) and 29 kg CO2/(ton PSA), respectively. Solids obtained through carbonation were pure calcium carbonate. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) in the soil have many positive effects on growth, nutrient acquisition, and stress tolerance of host plants, as well as soil fertility, soil structure, and soil ecology. Glomalin-related soil proteins (GRSP) are a mixture of humic substances and heat-stable glycoproteins, primarily of AMF origin. GRSP are as an important component of soil organic carbon (C) pools, which can stabilize and sequestrate C, thus reducing soil C emissions for slowing down global warming. Based on the CiteSpace software and the core collection of Web of Science as the database, this study made a visual analysis of GRSP's literature in the C field published from 1999 to 2022, including the number of publications, countries, institutions, co-cited literature, keywords, top cited papers, etc. The study regarding the GRSP in the C field could be divided into the initial stage (1999–2009), the steady stage (2010–2018), and the explosive stage (2019–2022). The Chinese Academy of Sciences is the organization with the most publications, and the United States, China, and India are the three leading nations in the C field of GRSP. However, there was little collaboration among the participating countries and the study's institutions. The focus of the research has shifted from the composition and content of GRSP in C to the question of whether C in GRSP affects soil properties. Future research was also prospected. [ABSTRACT FROM AUTHOR]

In the global ecosystem, wetlands are vital carbon sinks, playing a crucial role in absorbing greenhouse gases such as carbon dioxide and mitigating global warming. Accurate estimation of wetland carbon content is essential for research on wetland carbon sinks. However, the carbon cycle of wetlands is complex, and the carbon sinking of wetlands is affected by climate, topography, water level conditions, vegetation types, soil types, and other factors. This has caused significant challenges in the estimation of wetland carbon sinks. In current studies, most research has focused on the impact of individual factors on wetland carbon sinks, often ignoring the interaction between various factors, which further leads to uncertainty in wetland carbon measurements. This paper aims to elucidate the process of the wetland carbon cycle, summarize the factors affecting wetland carbon sinks, and explore the interplay between various factors and their influence on wetland carbon sinks, aiming to provide theoretical support for the study of wetland carbon sinks. Additionally, this paper reviews the advantages and disadvantages of current wetland carbon measurement methods, proposes research directions for combining machine learning methods, identifies existing difficulties in current wetland carbon measurement, and offers suggestions to serve as a reference for future wetland carbon sink estimation and wetland management.Highlights: The potential and significance of wetland carbon sinks are explained. The advantages and disadvantages of current wetland carbon measurement techniques are summarized. The prospective method for integrating machine learning into integrated wetland carbon measurement is proposed. [ABSTRACT FROM AUTHOR]

Carbon dioxide capture, utilization, and storage (CCUS) technology is an emerging technology with large-scale emission reduction potential and an essential component of the global response to climate change to achieve net-zero goals. As the two most important countries in global climate governance, it is necessary to review and examine the current status and trends of research in the field of CCUS in China and the USA. This paper uses bibliometric tools to review and analyze peer-reviewed articles in the Web of Science from both countries during 2000–2022. The results show a significant increase in research interest among scholars from both countries. The number of publications in the CCUS field in China and the USA was 1196 and 1302, respectively, showing an increasing trend. China and the USA have become the most influential countries in CCUS. And the USA has a more significant academic influence on a global scale. Furthermore, the research hotspots in the field of CCUS are diverse and differentiated. That is, China and the USA pay attention to different research hotspots or have different focuses in different periods. This paper also finds that new capture materials and technology development, geological storage monitoring and early warning, CO2 utilization and new energy development, sustainable business models, incentive policies and measures, and public awareness are critical directions for future research in the field of CCUS, to provide a comprehensive review and comparison of CCUS technology development in China and the USA. It helps to gain insight into the research differences and linkages between the two countries in the field of CCUS and identify the research gaps between them. And place some consensus that policymakers can use. [ABSTRACT FROM AUTHOR]

The double-carbon goal proposal has made it imperative for China's power industry to address the urgent issue of reducing greenhouse gas emissions from coal-fired power plants and promoting their clean and efficient use. A new approach to achieving peak-shaving and improving grid stability is the combination of carbon capture and storage (CCS) facilities with coal-fired power plants, which offers a strategic solution for mitigating climate change. Nonetheless, the viability of CCS retrofitting for coal-fired power plants in China hinges on its economic feasibility. The technical characteristics, economic analysis, and policy implications of clean coal-fired power plant equipped with CCS (CCP-CCS) technologies are evaluated in the paper. A comparison of the characteristics of different clean coal power generation technologies, including capacity, efficiency, coal consumption, and environmental performance, is conducted. The paper analyzes the economic feasibility of four typical clean coal power generation technologies, namely Supercritical (SC), Ultra-supercritical (USC), Integrated Gasification Combined Cycle (IGCC), and Circulating Fluidized Bed (CFB), both with and without CCS, using the levelized cost of electricity (LCOE) model. Financial parameters, investment parameters, operation and maintenance parameters, tax parameters, and capacity parameters are all considered in the LCOE model. The results indicate: (1) If CCS is not installed, the LCOE of USC power plants is the lowest at 0.37 yuan/kWh, while the LCOE of IGCC power plants is the highest at 0.44 yuan/kWh. (2) If CCS is installed, the LCOE of CFB units is the highest at 0.74 yuan/kWh, while the LCOE of USC units is the lowest at 0.60 yuan/kWh. (3) In sensitivity analysis, coal prices have the most significant impact on LCOE, followed by expected annual operating hours, while the cost of carbon capture equipment is the least sensitive. (4) The cost of retrofitting CCS on clean coal-fired power plants (CCP) is currently high, with an LCOE increase of around 40 to 70%, which is comparable to that of renewable energy electricity. This paper presents policy recommendations, including preferential loans, tax incentives, and R&D funding, to promote the development of CCP in China based on the economic analysis results and challenges faced by CCP. Additionally, the paper proposes relevant policy implications such as preferential loan policies, a diversified financing system, R&D and innovation, and the establishment of a carbon trading market for CCS in China to provide practical guidance for the promotion of CCP-CCS technologies in China. [ABSTRACT FROM AUTHOR]

The paper deals with the application of microalgae in building's façade, regard to the broader project comprising the aspects of the environmental comfort of academic spaces and the energy consumption with on-grid photovoltaic generation, as well as the investigation of alternatives for the improvement of the performance of the building envelopes. Thus, its main objective is the application of interdisciplinary concepts involving Architecture and Biotechnology, as known by Black Ecologies, referring to an investigative interest to explore a new approach of nature, not only related to architectural space, but an emergent environmental focus. This relationship is performed by using photobioreactors with microalgae, installed on the façades of buildings for educational use. The present work presents the methodological outline of the research, based on literature review and case studies; complementary experimental methodologies are also presented to contextualize the subject and its application and feasibility. The current state of art showed an emergent approach in terms of international level, but in the Brazilian context any further research was identified yet. In addition to thermal and energy performance, the strategies will allow the process of sequestration of carbon dioxide and other GHG (greenhouse gases) that impacts on the process of climate change and can contribute to reach the sustainable development. This subject coincides with the discussions of the 2050 scenarios and emission reduction, which were faced at the recent COP-27 and its connections with an integrative way to contribute to the United Nations Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

The persistent reliance on coal has resulted in the accumulation of substantial coal gangue, a globally recognized problematic solid waste with environmental risks. Given the coal gangue properties and global land degradation severity, the resourceful utilization of coal gangue as soil conditioners is believed to be a universally applicable, cost-effective, high-demand and environment-friendly model with broad application prospect. The direct application of raw coal gangue faces challenges of low active beneficial ingredients, inadequate water and fertilizer retention, presence of potentially toxic elements, resulting in limited efficacy and environmental contamination. This paper provided a comprehensive review of various modification methods (including mechanical, chemical, microbiological, thermal, hydrothermal and composite modifications) employed to enhance the soil improvement performance and reduce the environmental pollution of coal gangue. Furthermore, an analysis was conducted on the potential application of modified coal gangue as a muti-function soil conditioner based on its altered properties. The modified coal gangue is anticipated to effectively enhance soil quality, exhibiting significant potential in mitigating carbon emissions and facilitating soil carbon sequestration. This paper provided innovative ideas for future research on the comprehensive treatment of coal gangue and restoration of degraded soil in order to achieve the dual goals of zero-coal gangue waste and sustainable agriculture. [ABSTRACT FROM AUTHOR]

Estimating gross primary production (GPP) of terrestrial ecosystems is important for understanding the terrestrial carbon cycle. However, existed nationwide GPP datasets are primarily driven by coarse spatial resolutions (≥500 m) remotely sensed data, which fails to capture the spatial heterogeneity of GPP across different ecosystem types at land surface. This paper introduces a new GPP dataset, Hi-GLASS GPP v1, with a fine spatial resolution (30-m) and monthly temporal resolution from 2016 to 2020 in China. The Hi-GLASS GPP v1 dataset is generated from 30-m Landsat data using a process based light use efficiency model. The Hi-GLASS GPP v1 model integrates a detailed map of maize plantations, a crucial C4 crop in China known for its higher photosynthetic efficiency compared to C3 crops. This inclusion helps correct the underestimation of GPP that typically occurs when all croplands are categorized as C3. The Hi-GLASS GPP v1 dataset demonstrates a robust correlation with GPP data derived from eddy covariance towers, thereby enabling a more accurate assessment of terrestrial carbon sequestration across China. [ABSTRACT FROM AUTHOR]

Background: Reliable infrastructure is vital for Nordic societies, but they face escalating climate risks. Climate change is increasing magnitude and frequency of floods, storms, and landslides, making adaptive solutions crucial. Methods: This review explores Nature-Based Solutions (NbS) for mitigating natural hazards along Nordic linear infrastructure. The motivation of the review comes as result of a preliminary survey conducted among to the main infrastructure managers in the Fennoscandian peninsula. The objective was to pinpoint the natural hazards that pose greatest concern under future climate scenarios, as well as to understand which specific information is needed to adopt NbS Results: Floods, erosion, landslides and rockfalls emerged as primary hazards of concern for the infrastructure owners, hence the review process was focused only on NbS aimed at mitigating the effects of these specific hazards. A total of 78 documents were identified from the review process and were integrated with examples and case studies from other relevant on-going and past projects. Despite only a few of the NbS identified in these documents were directly implemented for linear infrastructure such as roads and railways, and none dealing with electric grids, several NbS were identified to have a potential for implementation for Nordic linear infrastructure. A list of NbS options, not all implemented along linear infrastructure but with potential for it, is provided. This list is meant to serve as "vade mecum" for a quick and easy access to NbS as mitigation options for linear infrastructure managers in the Nordic Countries. The NbS are classified in green, blue, green/blue and hybrid approaches, and supported by examples of case studies both in the Nordic Countries as well as countries having similar climates. Conclusions: This review underlines the challenges and opportunities of adopting NbS. Challenges such as the lack of expertise, space and climate constraints, and path dependency on adoption of traditional infrastructure must be addressed to mainstream NbS. The review highlights the importance of standardization, European guidelines, and technical manuals in promoting NbS adoption among infrastructure managers, as well as the necessity of accounting for the wider co-benefits of NbS, including carbon sequestration, biodiversity and ecosystem services. This paper contributes to the understanding of NbS as potential natural hazards mitigation options for Nordic infrastructure networks in the face of evolving climate risks, providing valuable insights for infrastructure managers and policymakers alike. [ABSTRACT FROM AUTHOR]

Bioenergy with carbon capture and storage (BECCS) is considered as a future key technology to provide baseload electricity, heat, pulp, paper, and biofuels, while also enabling atmospheric carbon dioxide removal (CDR). Sweden seeks to lead the way in bringing this technology up to scale, introducing a EUR 3.6 billion reverse auction scheme to facilitate market entry of companies producing BECCS. We explore instrument design preferences among politicians, regulators, and prospective BECCS operators to identify trade-offs and explore feasible policy design. Based on 35 interviews with experts in the latent BECCS sector in Sweden, we identify under which circumstances prospective operators would be willing to place bids and discuss how actor preferences both align with and challenge auction theory. The analysis concludes that at least four dilemmas need attention. These concerns how to: (1) balance the state's demand for BECCS to be implemented already in 2030 against the prospective BECCS operators' fear of the winner's curse, i.e., a fear of bidding for a contract that turns out to be too costly to implement; (2) allocate contracts at the margin of the auctioneer's demand for BECCS without driving up costs; (3) design compliance mechanism to achieve effectiveness without undermining efficiency, and; 4) integrate the auction with the voluntary carbon market—if at all—in a manner that safeguards the environmental integrity of the auctions. [ABSTRACT FROM AUTHOR]

Despite the extensive amount of evidence in the literature regarding the benefits of agroforestry systems including carbon sequestration, soil erosion reduction, climate change resilience, biodiversity conservation and other ecosystem services, the adoption of agroforestry practices presents several barriers for farmers and other stakeholders, thus requiring comprehensive examination from the scientific community. We performed a systematic literature review following the methodology described in the PRISMA framework, to provide a novel comprehensive and systematic overview of what is present in the literature regarding the obstacles stakeholders perceive with regards to agroforestry adoption, gathered through participatory research methods, which are methodologies that engage stakeholders in the research process. In this work, we highlighted and categorized 31 obstacles that stakeholders around the globe perceive according to the examined literature (n = 90) with regards to agroforestry adoption, pertaining to i) technical-agronomic, ii) socio-economic and iii) policy-legislative aspects. We produced a consultable database of the examined literature presenting the extracted and categorized data including 1) Region of interest; 2) Investigated agroforestry system; 3) Methodologies utilized in the papers; 4) Number, gender ratio and type of stakeholders; 5) Main relevant obstacles found in the paper. We highlighted the five most frequently encountered issues i) the availability or quality of knowledge or experience on technical and agronomic matters, or knowledge diffusion necessary to implement or maintain agroforestry systems ii) the perceived socio-economic issue related to the market, marketing of agroforestry products, supply chain or jobs in agroforestry; iii) issues related to the amount of labor or time necessary to implement or maintain agroforestry systems; iv) issues related to the upfront economic investment necessary to establish an agroforestry system and availability of capital; and v) issues related to the availability of technical support necessary to implement or maintain agroforestry systems. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of using circularity indicators is to show the effect of changes from linear to more circular systems. This paper contributes to highlighting the importance of methodological aspects of circularity indicators in the agricultural sector when using a life cycle thinking approach. Selected circularity indicators have been explored and compared with LCA impact categories by using them to evaluate the circularity of a livestock system. Methods: Circularity indicators were tested on a theoretical pig production system where several circularity strategies and associated mitigation actions were applied. The strategies and mitigation actions were as follows: anaerobic digestion of manure (closing resource loops), anaerobic digestion of bread waste (closing resource loops), precision fertilization (narrowing resource loops), use of cover crops in feed production (regenerating resource flows), and use of bread waste as feed (slowing resource loops). The functional unit was 1 kg pork as carcass weight, and the treatment of 1.1 kg bread waste for all impact categories and indicators. For each mitigation action, relevant circularity indicators were tested. Based on this, the functionality and suitability of these indicators were discussed. Results and discussion: Four of the circularity indicators were based on nitrogen (N) or phosphorus (P) substances: N recycling index, partial N balance, consumption of fossil-P fertilizers, and emissions to water bodies (P). Even if the indicators do not capture the impact of emissions of N and P as the eutrophication impact categories, they provide a useful indication of the circularity of a system. The other three circularity indicators tested were as follows: renewable energy production, soil organic carbon, and land use ratio. The renewable energy production indicator is easy to understand and communicate and provides unique information. Soil organic carbon presents a potential for soil carbon sequestration. Land use ratio is based on the same data as land occupation but provides an assessment of whether feed production competes for the suitable area for food production by including production of human-digestible protein. Conclusions: Circularity indicators provide valuable information about the circularity of an agricultural product system. The circularity indicators and LCA impact categories can be used either separately or together, or to complement each other. The choice of indicators depends on the questions raised, i.e., goals and scope, and it is therefore important to have a number of circular indicators to choose from in order to achieve a comprehensive assessment. [ABSTRACT FROM AUTHOR]

This study is a contribution to the ongoing debate about the selection of the approach for carbon accounting in wood products to be used, in the future, in the national greenhouse gas inventories under the UNFCCC (United Nations Framework Convention on Climate Change). Two accounting approaches are used in this analysis: the stock-change approach and the atmospheric-flow approach. They are applied to the Portuguese Eucalyptus globulus forest sector. To achieve this objective, the fluxes of wood removed from the forest are tracked through its life cycle, which includes products manufacture (mainly pulp and paper), use and final disposal (landfilling, incineration and composting). This study develops a framework to the estimation of carbon sequestration in the forest of E. globulus, a fast growing species, more specifically, in the calculation of the conversion factors such as bark and foliage percentages and densities, used to convert wood volumes into total biomass. A mass balance approach based on real data from mills is also proposed, in order to assess carbon emissions from wood processing. The results show that E. globulus forest sector was a carbon sink, but the magnitude of the carbon sequestration differs substantially depending on the accounting approach used. The contribution of the forest ecosystem was smaller than the aggregated contribution of wood products in use and in landfills (including industrial waste), which reinforces the role that wood products play in national carbon budgets. [ABSTRACT FROM AUTHOR]

A method is suggested for estimating additions to carbon stored in harvested wood products (HWP) and for evaluating uncertainty. The method uses data on HWP production and trade from several decades and tracks annual additions to pools of HWP in use, removals from use, additions to solid waste disposal sites (SWDS), and decay from SWDS. The method is consistent with IPCC guidance for estimating emissions from SWDS. Uncertainty is postulated in the form of probability density functions for 14 variables, using Monte Carlo simulation. Results for the United States suggest that uncertainty is most sensitive to uncertainty in production data for solidwood products, the factor used to convert products to carbon, and the proportion of solidwood and paper in SWDS. Uncertainty in the use (service) life of solidwood products has a limited effect because an error offsets changes in products in use and in SWDS. The method provides a starting point for meeting the aims of the IPCC Good Practice Guidance. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Quantification of density-driven natural convection for dissolution mechanism in CO2 Sequestration," by Rasoul Nazari Moghaddam and Behzad Rostami in the 2011 issue.

A response by Rasoul Nazari Moghaddam and Behzad Rostami to a letter to the editor on their article "Quantification of density-driven natural convection for dissolution mechanism in CO2 sequestration," in the 2011 issue, is presented.

Kirschbaum (Mitig Adapt Strat Glob Change 11:1151-1164, 2006) explores the climatic impact over time of temporarily sequestering carbon from the atmosphere. He concludes that temporary storage of carbon in the terrestrial biosphere ''achieves effectively no climate-change mitigation''. His strongly worded statement begs for a response. This paper argues that Kirschbaum's conclusion is an artifact of the specific perspective of his analysis and his choice of a definition for climate-change impact. Even temporary sinks put us on a lower path for climate change, a path that will not otherwise be accessible. For carbon sinks in the terrestrial biosphere, we argue that sooner is better and longer is better, but even known temporary sinks have value. [ABSTRACT FROM AUTHOR]

The challenges posed by climate change, biodiversity loss, and land-use are deeply interconnected and integrated solutions are needed. This paper presents results from 11 contributions to a special issue covering topics of integrated modeling and spatial prioritization, mass-balance studies, Earth Observation techniques, research infrastructure developments, and evaluation of policy measures and economic compensation schemes. The spatial scale of the studies ranges from detailed site-specific to a European scale. This paper briefly summarizes the main findings of these studies, makes some general overall conclusions, and identifies topics for further research and methods developments. [ABSTRACT FROM AUTHOR]

Rising atmospheric CO2 may stimulate future forest productivity, possibly increasing carbon storage in terrestrial ecosystems, but how tropospheric ozone will modify this response is unknown. Because of the importance of fine roots to the belowground C cycle, we monitored fine-root biomass and associated C fluxes in regenerating stands of trembling aspen, and mixed stands of trembling aspen and paper birch at FACTS-II, the Aspen FACE project in Rhinelander, Wisconsin. Free-air CO2 enrichment (FACE) was used to elevate concentrations of CO2 (average enrichment concentration 535 µl l–1) and O3 (53 nl l–1) in developing forest stands in 1998 and 1999. Soil respiration, soil pCO2, and dissolved organic carbon in soil solution (DOC) were monitored biweekly. Soil respiration was measured with a portable infrared gas analyzer. Soil pCO2 and DOC samples were collected from soil gas wells and tension lysimeters, respectively, at depths of 15, 30, and 125 cm. Fine-root biomass averaged 263 g m–2 in control plots and increased 96% under elevated CO2. The increased root biomass was accompanied by a 39% increase in soil respiration and a 27% increase in soil pCO2. Both soil respiration and pCO2 exhibited a strong seasonal signal, which was positively correlated with soil temperature. DOC concentrations in soil solution averaged ~12 mg l–1 in surface horizons, declined with depth, and were little affected by the treatments. A simplified belowground C budget for the site indicated that native soil organic matter still dominated the system, and that soil respiration was by far the largest flux. Ozone decreased the above responses to elevated CO2, but effects were rarely statistically significant. We conclude that regenerating stands of northern hardwoods have the potential for substantially greater C input to soil due to greater fine-root production under elevated CO2. Greater fine-root biomass will be accompanied by greater soil C efflux as soil respiration, but leaching losses of C will probably be unaffected. [ABSTRACT FROM AUTHOR]

The "Dual Carbon" initiative is a two-stage carbon reduction goal proposed by China, with significant implications for global climate change mitigation. This article examines the impact of the "Dual Carbon" strategy on China's forestry development and explores how to leverage this strategy to facilitate the transformation and advancement of the forestry sector. Current review indicated that forestry has the advantage of achieving higher emission reduction targets at a low cost. Starting with an overview of the "Dual Carbon" strategy, this paper analyzes the carbon sequestration potential of plants and soil, and the challenges and opportunities faced by forestry development under this framework. Furthermore, we outline implementation pathways for forestry development, aiming to provide insights for the progress of China's forestry sector. Overall, it should be noted that the priority is to vigorously develop timber resources, and we also need to vigorously develop and protect forestry talent with the support of China's policies. By trapping into the carbon storage capabilities and leveraging carbon trading mechanisms of forests, a favorable ecological environment can be created, thus achieving the goal of carbon neutrality. Highlights: • Forest development and its carbon sinks, attributed to plant and soil have the potential in carbon sequestration process, thus helping China achieve carbon neutrality. • The supply of forest products and the balance of economic growth and environmental protection are the key difficulties under the "Dual Carbon" strategy. • Trading forest carbon sinks can boost China's sequestration. [ABSTRACT FROM AUTHOR]

Sequestering CO2 in depleted oil reservoirs provides one of the most appealing measures to reduce greenhouse gases (GHG) concentration in the atmosphere. The remaining liquids after enhanced oil recovery (EOR) processes, including residual oil and remaining water, lead to the main challenges to this approach. How to effectively evacuate a depleted oil reservoir by recovering not only residual oil but also remaining water is a critical consideration for this type of CO2 sequestration. This paper presents conceptual investigations concerning the methods which effectively evacuate depleted oil reservoirs from both the displacement efficiency and the sweep efficiency points of view. To improve the displacement efficiency, surfactant slug and solvent slug injection was examined using a core scale numerical model. Investigations regarding improving sweep efficiency, such as horizontal well pattern infilling and foam injection, were carried out based on a typical row well pattern. Simulation results showed that surfactant slug which modified the relative permeability and capillary pressure remarkably reduced both residual oil saturation and remaining water saturation. A CO2 slug injected before surfactant slug can help improve the oil recovery. Solvent enriched CO2 slug also remarkably reduced the residual oil saturation to as low as 2%. Horizontal well pattern infilling had great advantage for thick or inclined reservoirs, and foam slug injection greatly improved CO2 storage capacity in thin reservoirs by improving the sweep efficiency. Maximum mobility reduction (MRF) is the most important parameter to maximize the storage capacity and the benefit. The variation of CO2 storage capacity along with CO2 slug size. Larger foam slug size will play a better storage performance. The conceptual simulation investigations confirmed that depleted oil reservoirs can be effectively evacuated for CO2 storage. Depleted oil reservoirs with maximum evacuation are the best candidates for CO2 sequestrations. [ABSTRACT FROM AUTHOR]

The current paper aims to assess the effects of landscape change in a mountain river basin in the north of Iran through quantifying, mapping, and assessing carbon storage. The analyses were performed based on previous alterations in land use and land cover (LULC) (1988–2018) and on expected changes determined by three LULC alteration setups for 2048. The Landsat imagery from 2018, 2008, 1998, and 1988 was used for evaluating and predicting the spatiotemporal distributions of LULC changes. The future LULC image prediction has been generated using Land Change Modeler (LCM) module of TerrSet software for the years 2028, 2038, and 2048. Validation was carried out by overlaying the actual and projected to 2018 map. We integrated the Markov Chain (MC) and InVEST Carbon Storage and Sequestration (InVEST-CSS) models for simulating the ecosystem carbon storage and the long-term monetary valuation. In this process, we considered social costs/economic value because of the area's loss and gain of stored carbon. The results show that forests and rangelands with good and poor conditions decreased by 631.2, 10,374, and 10,254 ha, respectively, from 1988 to 2018. Overall, modeling and mapping LULC changes showed a descending trend in forests (0.66%), agriculture (0.1%), and rangelands (4.1%) in 2048. In addition, carbon storage has already been lost by 9.9 million tons (76.98 ha−1) from 1988 to 8.8 million tons (68.86 ha−1) in 2018 and is expected to have an 8.4 million tons (65.25 ha−1) loss by 2048. Monitoring the economic value of carbon storage from 1988 to 2018 shows a loss of $US 15684338 (121.8 ha−1) and estimates a loss of $US6972622 (54.18 ha−1) by 2048. Therefore, spatiotemporal design of InVEST model by estimating the carbon value over time focuses on continuous monitoring actions for both the carbon pools dynamic and LULC pattern. This consideration causes reduction the uncertainty of estimated models and also increases the continuous cost of those changes. This will help government and decision makers for long-term and accurate carbon sequestration strategies for ecosystem. [ABSTRACT FROM AUTHOR]

The present energy demand of the world is increasing but the fossil fuels are gradually depleting. As a result, the need for alternative fuels and energy sources is growing. Fuel cells could be one alternative to address the challenge. The fuel cell can convert CO2 to value-added chemicals. The potential of bio-fuel cells, specifically enzymatic fuel cells and microbial fuel cells, and the importance of immobilization technology in bio-fuel cells are highlighted. The review paper also includes a detailed explanation of the microbial electrosynthesis system to reduce CO2 and the value-added products during microbial electrosynthesis. Future research in bio-electrochemical synthesis for CO2 conversion is expected to prioritize enhancing biocatalyst efficiency, refining reactor design, exploring novel electrode materials, understanding microbial interactions, integrating renewable energy sources, and investigating electrochemical processes for carbon capture and selective CO2 reduction. The challenges and perspectives of bio-electrochemical systems in the application of CO2 conversion are also discussed. Overall, this review paper provides valuable insights into the latest developments and criteria for effective research and implementation in bio-fuel cells, immobilization technology, and microbial electro-synthesis systems. [ABSTRACT FROM AUTHOR]

To accelerate the low-carbon transformation of the power industry, a range of carbon emission reduction policies and technologies have emerged. However, the current China's carbon emissions trading (CET) policy is inadequate in encouraging power generation enterprises to take proactive measures towards emission reduction due to challenges like fixed and low carbon prices. The high proportion of renewable energy in electricity consumption also faces significant challenges due to the unpredictable nature of wind and PV energy. Therefore, this paper applies stepped CET mechanism, energy storage system (ES) system and carbon capture and storage (CCS) mechanism together to hybrid renewable energy system, aiming to study their synergistic carbon emission reduction effect. Firstly, the paper constructs the stepped CET model considering incentives and penalties. Secondly, the stepped CET model, ES system and CCS are jointly introduced into the hybrid renewable energy system. Finally, a scenario analysis is conducted to investigate the synergistic effect of various carbon emissions reduction policies and technologies in the operation of power generation systems. The results show that: i) compared with traditional CET, the stepped CET increases renewable energy consumption by 0.12% and reduces carbon emissions by 0.6%; ii) the introduction of stepped CET and ES equipment together consumes an additional 36.1% of renewable energy and reduces carbon emissions by 32.4%; iii) based on stepped CET model and ES equipment, the introduction of CCS system reduces carbon emissions by 29.4%. [ABSTRACT FROM AUTHOR]

Integrated simulation models are commonly used to provide insight on the complex functioning of social-ecological systems, often drawing on earlier tools with a narrower focus. Forest sector models (FSM) encompass a set of simulation models originally developed to forecast economic developments in timber markets but now commonly used to analyse climate and environmental policy. In this paper, we document and investigate this evolution through the prism of the inclusion of several non-timber objectives into FSM. We perform a systematic, quantitative survey of the literature followed by a more in-depth narrative review. Results show that a majority of papers in FSM research today focuses on non-timber objectives related to climate change mitigation, namely carbon sequestration and bioenergy production. Habitat conservation, deforestation and the mitigation of disturbances are secondary foci, while aspects such as forest recreation and many regulation services are absent. Non-timber objectives closest to the original targets of FSM, as well as those for which economic values are easier to estimate, have been more deeply integrated to the models, entering the objective function as decision variables. Others objectives are usually modelled as constraints and only considered through their negative economic impacts on the forest sector. Current limits to a deeper inclusion of non-timber objectives include the models' ability to represent local environmental conditions as well as the formulation of the optimisation problem as a maximisation of economic welfare. Recent research has turned towards the use of model couplings and the development of models at the local scale to overcome these limitations. Challenges for future research comprise extensions to other non-timber objectives, especially cultural services, as well as model calibration at lower spatial scales. [ABSTRACT FROM AUTHOR]

Nature-based solutions are gaining momentum as approaches to address major environmental challenges, including markets for soil carbon (C) sequestration for mitigating climate change. This special collection of papers, stemming from a symposium of the 2021 Fall Meeting of the American Geophysical Union, poses several tough questions about the practical potential for significant C sequestration resulting from farmer participation in carbon markets. A common theme among these papers is that promotion of soil C sequestration through carbon markets has likely gotten ahead of the agronomic and biogeochemical science and especially the social science. We know a great deal about soil C dynamics and stabilization, but we know less about translating that knowledge to market-based solutions that have inherent challenges of validating sequestration rates and other potential pitfalls. Scientists can help provide rigor to carbon markets, although they must maintain objectivity and avoid conflicts of interests with well-intended evolving markets. Even when there is strong scientific support for the feasibility and the virtues of best management practices that provide numerous co-benefits while building soil organic matter, socio-economic barriers to farmer adoption remain poorly understood. Although soil markets currently focus almost exclusively on C, mitigation of methane and nitrous oxide emissions from agriculture could offer several advantages as well as challenges. The papers in this special collection offer a needed perspective urging soil scientists, biogeochemists, and social scientists to step up and offer honest appraisals of what is most likely to work, or not, and why. [ABSTRACT FROM AUTHOR]

The regulation of the pyrolysis process is a key step in increasing the carbon sequestration capacity of biochar. The effect of K3PO4 addition on the yield, chemical composition, characteristic functional groups, macromolecular skeleton, graphite crystallites, and stability of biochar was studied in this paper using two-dimensional infrared correlation spectroscopy (2D-PCIS), X-ray photoelectron spectroscopy, Raman spectrum, and other characterization methods combined with thermal/chemical oxidation analysis. It is discovered that adding K3PO4 may effectively minimize the graphitization temperature range and increase biochar's yield, aromaticity, H/C ratio, and proportion of refractory/recalcitrant organic carbon. The 2D-PCIS and Raman analysis revealed that K3PO4 mostly promoted the dehydrogenation and polycondensation process of the aromatic rings in the char precursor, transforming the amorphous carbon structure of biochar into an ordered turbostratic microcrystalline structure. K3PO4 enhanced biochar stability mostly at medium-high temperatures (350 ~ 750℃) by stimulating the transformation of unstable structures of biochar to stable carbon-containing structures or by inhibiting the interaction of its active sites with oxidants through the mineralization process. A 20% phosphorus addition increased biochar's refractory index (R50) by roughly 11%, and it also boosted biochar's oxidation resistance (H2O2 or K2CrO4) efficiency, reducing carbon oxidation loss by up to 7.31%. However, at higher temperatures (> 750 ℃), the doping of phosphorus atoms into the carbon skeleton degraded the biochar structure's stability. The results of this study suggest that using exogenous phosphorus-containing additives is an efficient way to improve the stability of biochar. Highlights: K3PO4 promoted biochar precursor's dehydrogenation/polycondensation process to form fused-ring aromatic structures. K3PO4 increased recalcitrant carbon proportion and shielded biochar's active sites through the mineralization process. By adding 20 wt% of K3PO4, the thermal and chemical stability of biochar were enhanced by 11% and 7%, respectively [ABSTRACT FROM AUTHOR]

Lowering the embodied carbon of building materials requires a transition away from fossil derived products towards bio-based alternatives, alongside the design and development of new clean tech biomaterials that can function as carbon sinks. This paper presents an overview of historical and existing uses of seaweeds in construction to identify gaps and opportunities for the development of seaweed-based construction materials that can support atmospheric carbon removal through algal photosynthesis. This study highlights the value of interdisciplinary research collaborations that can be situated within the expanding field of biodesign where design research and methods are used to influence the development materials science. It presents as a case study the design of seaweed bricks utilising a biorefinery framework that aims to valorise residual seaweed biomass being grown for waste-water management, identifying value-adding opportunities for this seaweed by-product and new possibilities for carbon storage in the built environment. It details the development of a 1:1 scale prototype for the purposes of an exhibition at the Art Gallery of South Australia in order to demonstrate what biomasonry products from macroalgae can look like, to build social acceptance and to encourage future uptake of sustainable seaweed construction products. [ABSTRACT FROM AUTHOR]

Cement production contributes significantly to anthropogenic greenhouse gas emissions (GHG), a major contributor to global carbon emissions. The environmental impacts of cement production have grown in recent years and it is urgent to reduce its carbon footprint. Systems dynamics (SD) is a simulation method used to understand the nonlinear behavior of complex systems over time. It is commonly used in various sectors to predict emissions and conduct policy experiments. Due to the poor implementation of carbon mitigation strategies within the cement industry, enhancing policymaking by employing more advanced decision-support tools is necessary. This paper reviews previous studies that use the SD approach to assess and compare different mitigation strategies proposed and implemented to reduce carbon emissions in the cement industry. These strategies encompass technological advancements and process improvements, including using alternative fuels and raw materials (adopting low-carbon cementitious materials), energy efficiency improvements, carbon capture and storage and waste heat recovery. The review examines the papers' scope, model descriptions, validation method and mitigation methods highlighted in each study, providing valuable insights for decision makers in the cement industry. Furthermore, the paper discusses the limitations and gaps related to SD modeling, highlighting important factors such as stakeholder engagement in designing effective carbon mitigation strategies. The reviewed studies constantly emphasized technical strategies for mitigating carbon emissions from the cement industry, as stated by the International Energy Agency (IEA) classification. Innovative and emerging technologies, such as WHR, depends on adequate funding, motivation and research and development. However, they frequently neglected to address the barriers hindering their implementation or provide detailed policy measures to overcome them using SD. Additional research is required to assess the practicality and costs of implementing these strategies. Navigating the way to sustainability in the cement industry: Exploring mitigation strategies through systems dynamics model [ABSTRACT FROM AUTHOR]

Context: Woody plant encroachment has remarkably altered the structure and functioning of savanna and grassland ecosystems and has become a major ecological concern globally. The majority of the studies/reviews on woody plant encroachment have overwhelmingly concentrated on the negative impacts of the phenomenon and have ignored its benefits to humans. Objectives: The current paper addresses the question whether woody plant encroachment is bad and goes further to discuss its benefits. Methods: This review is based primarily on published papers that were procured from the Google Scholar database, utilizing keywords that relate to woody plant encroachment and its impacts. Results: Woody plant encroachment usually reduces grass cover and results in substantial accumulation of carbon and nutrients in the soil and vegetation as grasslands/savannas become more densely wooded. It appears to have a more drastic impact on commercial farmers in North and South America than small-scale farmers and pastoralists in Africa, South America and Asia, who derive benefits such as increased supplies of fuelwood, medicine, food and browse for livestock from the phenomenon. Conclusion: Woody plant encroachment should not be regarded as patently unwholesome because of its overarching benefit of carbon sequestration in soil and woody plants in grasslands/savannas that help to mitigate climate change and global warming. Shade-loving grasses that provide fodder for livestock could be planted in rangeland to ameliorate the effect of reduced herbage production. [ABSTRACT FROM AUTHOR]

Wetlands provide numerous ecological and economic services to mankind. The soils of wetlands are one of the largest sinks of carbon (C) among the terrestrial ecosystems and can play an important role in offsetting the emission of C as a greenhouse gas (GHG) to the atmosphere. India is bestowed with enriched wetland ecosystems that support diverse and unique habitats. The potential of the wetlands in terms of C capture and sequestration has not been quantified. Therefore, in the present paper, an assessment of C capture from different sources and its ultimate deposition in soils leading to sequestration has been done in three different types of wetlands, one created sewage-fed and two natural floodplain oxbow lakes, in the West Bengal state of India. Multiple seasonal sampling of water, macrophytes, and soil was done to assess the primary productivity, dissolved C, and deposition of C in soils of the wetlands in comparison to reference upland sites. All these wetlands are productive ecosystems as indicated by the physicochemical parameters of water and soil. The quantity of C accumulated up to 0.3 m depth in the oxbow lakes was to the tune of 144–166 Mg/ha, which was 3.43–4.78 times higher than that in the corresponding reference upland sites. In the sewage-fed wetland, the C accumulation estimated as 50 Mg/ha was 1.27 times higher than its corresponding upland site. So, the wetland ecosystems, particularly the floodplains, are highly efficient in accumulating C in their soils and thus can somewhat negate the GHG emission. [ABSTRACT FROM AUTHOR]

Various industries around the world recognize the importance of achieving Net Zero Greenhouse Gases (GHG) emission by 2050. Industrial processes have been attributed to the increase in CO2 concentrations causing climate change. As the rate of emissions continues to increase, there becomes a pressing need to adopt new technologies that allow for a real shift towards emission reduction. In this paper, Carbon Capture (CC) technologies are explored and reviewed across various industries namely: cement, steel, ethanol and powerplants. A statistical representation of various CC implementations and facilities is presented with a supportive case study, including some evaluative discussions of energy demands, capture rates, and economic impacts of various technology adoptions. Moreover, the paper includes a comparative data analysis of various solvents and configurations used for carbon capture, to show their effectiveness in reducing CO2 and cost of implementation. The paper also discusses some crucial limitations and challenges of CC, including economic and technical aspects. However, with the success seen in CC applications across various industries, there remains scope for future work to address novel solvents, with reduced costs and minimum modifications to existing processes. A brief overview of life cycle assessment of carbon capture and storage is also presented. [ABSTRACT FROM AUTHOR]

Accounting for ecosystems is increasingly central to natural capital accounting. What is missing from this, however, is an answer to questions about how natural capital is distributed. That is, who consumes ecosystem services and who owns or manages the underlying asset(s) that give rise to ecosystem services. In this paper, we examine the significance of the ownership of land on which ecosystem assets (or ecosystem types) is located in the context of natural capital accounting. We illustrate this in an empirical application to two ecosystem services and a range of ecosystem types and land ownership in Scotland, a context in which land reform debates are longstanding. Our results indicate the relative importance of private land in ecosystem service supply, rather than land held by the public sector. We find relative concentration of ownership for land providing comparatively high amounts of carbon sequestration. For air pollution removal, however, the role of smaller to medium sized, mostly privately owned, land holdings closer to urban settlements becomes more prominent. The contributions in this paper, we argue, represent important first steps in anticipating distributional impacts of natural capital (and related) policy in natural capital accounts as well as connecting these frameworks to broader concerns about wealth disparities across and within countries. [ABSTRACT FROM AUTHOR]

To achieve the goal of urban carbon dioxide emission reduction, how to increase carbon sequestration has become a top priority. The biological sink is mainly divided into green carbon sink and blue carbon sink. Coastal cities have two kinds of carbon sinks. There, the study of carbon sinks in coastal cities is the primary choice to cope with climate change. Therefore, this study chooses coastal cities with primary industries including agriculture, fishery, and forestry as the study subjects. The LMDI (Log-Mean Divisia Index) method and multiple regression prediction models were used to explore the low-carbon countermeasures which increase urban net carbon sink from the perspective of influencing factors and future potential. The study found that the average output value of employees in the primary industry is the main driving factor, and the change in the purchasing power of unit carbon sinks and the change in the proportion of employees in the primary industry have inhibited the increase in net carbon sinks. Projections based on the primary industry's output and afforestation area as independent variables show an overall upward trend in net carbon sinks, reaching 15.70 million tons of net carbon sinks in 2060, offsetting 10–20% of total carbon emissions in the same year. Based on the calculation results, this paper puts forward some corresponding countermeasures to increase carbon sinks. This paper provides a theoretical reference for the low-carbon development of coastal cities in China, and the strategies can be also expanded to other cities with similar resources around the world. [ABSTRACT FROM AUTHOR]

The article discusses research by Simon Lewis and colleagues investigating the role of forests in carbon sequestration. Topics include an overview of the research methodology used by the team to monitor African forests over a ten-year period, where carbon dioxide goes when not sequestered by the world's oceans, and how the study impacted the importance of collecting and archiving standardized data. Also discussed is the challenge of identifying each species of tree and their growth rates.

The cement industry is undeniably critical for the global economy. However, they are also the largest energy consumers in the world. The clinker manufacturing process causes gaseous emissions like nitrogen oxides, sulfur dioxide, carbon dioxide and particulate matter. There is scope for various technologies to be used in the cement manufacturing process for reducing emissions and energy consumption. This paper presents an analysis of various emission reduction approaches using alternative techniques/raw materials, energy saving (thermal and electrical) methods, process optimization/modifications, carbon capture and storage. However, financial and technical challenges remain significant barriers against sustainability initiatives in the clinker manufacturing process. Practical and feasible methods were applied to reduce nitrogen oxides, carbon dioxide and particulate matter emissions during the clinker manufacturing process. This study also shows the application of pinch technology for more economical energy usage. This study was conducted in the premises of Emami Cement Limited, Balodabazar (Chhattisgarh State), India. [ABSTRACT FROM AUTHOR]

Countries have pledged to different national and international environmental agreements, most prominently the climate change mitigation targets of the Paris Agreement. Accounting for carbon stocks and flows (fluxes) is essential for countries that have recently adopted the United Nations System of Environmental-Economic Accounting - ecosystem accounting framework (UNSEEA) as a global statistical standard. In this paper, we analyze how spatial carbon fluxes can be used in support of the UNSEEA carbon accounts in five case countries with available in-situ data. Using global multi-date biomass map products and other remotely sensed data, we mapped the 2010–2018 carbon fluxes in Brazil, the Netherlands, the Philippines, Sweden and the USA using National Forest Inventory (NFI) and local biomass maps from airborne LiDAR as reference data. We identified areas that are unsupported by the reference data within environmental feature space (6–47% of vegetated country area); cross-validated an ensemble machine learning (RMSE=9–39 Mg C ha - 1 and R 2 =0.16–0.71) used to map carbon fluxes with prediction intervals; and assessed spatially correlated residuals (<5 km) before aggregating carbon fluxes from 1-ha pixels to UNSEEA forest classes. The resulting carbon accounting tables revealed the net carbon sequestration in natural broadleaved forests. Both in plantations and in other woody vegetation ecosystems, emissions exceeded sequestration. Overall, our estimates align with FAO-Forest Resource Assessment and national studies with the largest deviations in Brazil and USA. These two countries used highly clustered reference data, where clustering caused uncertainty given the need to extrapolate to under-sampled areas. We finally provide recommendations to mitigate the effect of under-sampling and to better account for the uncertainties once carbon stocks and flows need to be aggregated in relatively smaller countries. These actions are timely given the global initiatives that aim to upscale UNSEEA carbon accounting. [ABSTRACT FROM AUTHOR]

Okra (Abelmoschus esculentus L. Moench) is a beneficial vegetable and oil crop that has found valuable use as food, paper, medicine, and oil. However, because of climate change, a lack of better okra cultivars that can resist drought has hampered okra production in sub-Saharan Africa (SSA) and across the world. This study aimed to investigate the economic production of this vegetable in a forest setting. The okra (A. esculentus L.) experiment was conducted underneath three forest trees (i.e. Albizia lebbeck, Melia azedarach, and Leucaena leucocephala) in the agroforestry area. A single-factor Randomised Complete Block Design (RCBD) with three replications was utilised. The sample was then separated into three groups: okra-L. leucocephala agroforestry, okra-M. azedarach agroforestry, and okra-A. lebbeck agroforestry. The findings of the study revealed that okra production had differed significantly in three agroforestry practices. The fresh okra yield was highest (10.20 ton/ha) in the okra-A. lebbeck agroforestry. The okra-L. leucocephala agroforestry (9.10 ton/ha) came in second, while the lowest yield was in the okra-M. azedarach agroforestry (8.90 ton/ha). Moreover, the okra-A. lebbeck agroforestry recorded the maximum benefit–cost ratio (3.97) for economic performance. This ratio was 21% and 14% higher compared to the respective performance of the okra-M. azedarach agroforestry and okra-L. leucocephala agroforestry. However, the highest amount of carbon sequestration (238.90 ton/ha/yr) was measured in the okra-M. azedarach agroforestry as well as (229.80 ton/ha/yr) in the okra-A. lebbeck agroforestry practice. Finally, the okra-A. lebbeck agroforestry practice would significantly increase production, touching financial benefit and ensuring sound environmental quality using the vacant woodlot space. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Reply to the Comments on the paper ‘Quantification of density-driven natural convection for dissolution mechanism in CO2 sequestration" in the 2012 issue.

Mangrove wetlands are among the four most productive tropical and subtropical ecosystems. They are also a core component of the coastal blue carbon ecosystem, which is of great ecological significance to human beings, plants, animals, and the global carbon balance. There has been a global decrease in the distribution of mangrove forests, and their ecological function has gradually degenerated since the Holocene. Sediment from coastal mangrove wetlands can provide records of climate change and human activities, and multiple proxies including palynology, leaf fossil, biomarkers, DNA, phytolith and stable isotopes, can be used to reconstruct the evolutionary stages of paleo-mangroves and to identify the effect of natural processes and human activities on the distribution and evolution of mangroves. This information can provide theoretical support for mangrove protection and for improving carbon sequestration capacity. This paper summarizes and compares the multiple proxies for mangrove reconstruction, reviews progress in the study of natural succession of global mangroves since the Holocene, expands on the influence mechanisms of human activities on mangrove growth and development and uses past information to lay a foundation for a model to predict future mangrove development. [ABSTRACT FROM AUTHOR]

In the field of fuzzy sets, distance measures can effectively quantify the relevant uncertainty. Regarding hesitant fuzzy sets (HFSs), improved hesitant fuzzy distance measures have recently been proposed by fusing classical distance measures with hesitation degrees, and the corresponding information enrichment can be probabilistically advanced to pursue new distance measures of probabilistic hesitant fuzzy sets (PHFSs). Aiming at PHFSs, the improved distance measures of HFSs are simulated and extended in this paper, and thus improved distance measures of PHFSs are proposed; the new PHFSs distances are utilized to construct a new method of probabilistic hesitant fuzzy decision-making, called MEREC-TODIM. Firstly, the new probabilistic hesitant fuzzy Hamming distance and Euclidean distance are directly and parametrically established by incorporating hesitation degrees; accordingly, the improved distance measures exhibit a 2 × 2 system on (non-parameter, parameter) and (Hamming, Euclidean), and their distance property, measure size, parameter monotonicity, and promotion degeneration are investigated and acquired. Furthermore, a modified score function is proposed for MEREC to determine attribute weights, and thus a corresponding decision method with TODIM (i.e., MEREC-TODIM) is established for PHFSs applications on evaluation sorting and optimization selection. Finally, MEREC-TODIM is validated through parameter analyses and decision comparisons, and it is effectively applied to two practical examples: Carbon Capture Utilization Storage and PhD Admission Interviews. Highlights: PHF Hamming and Euclidean distances fusing hesitation degrees provide extensions on HFSs and improvements on PHFSs. An improved score function considering deviation degrees emerges to induce MEREC for attribute weight determination. Improved measures-based TODIM and MEREC constitute MEREC-TODIM decision making with validity and performance. [ABSTRACT FROM AUTHOR]

Carbon capture systems and the utilization of renewable energy are key ways to reduce carbon emissions, but their uncertainty seriously affects the stable operation and economic efficiency of power systems. To tackle this challenge, a low-carbon economic scheduling model for microgrid electric-thermal integrated energy systems(IES) considering uncertainties is proposed in this paper. The model suggests an ideal dispatch of the IES system that accounts for the disruption of the carbon capture system's integration into the grid belt and plans for the carbon capture plant's low carbon features. Mechanisms for operating and scheduling systems couple wind energy with carbon capture power plants. These mechanisms also invoke demand response resources on the load side. The system's low carbon performance is increased through cooperative source–load resource optimization. A well-established industrial automation optimal dispatch model is developed using YALMIP and CPLEX. The results show that this method is helpful to solve the problem of system adaptability and seek a balance between low-carbon and economy. When considering uncertainties, the ability to resist risks of the system is improved, but the cost will increase by about 3 % . [ABSTRACT FROM AUTHOR]

Carbon sequestration in terrestrial vegetation can't be underestimated in terms of offsetting CO2 emissions from energy consumption. However, it is not clear to what extent terrestrial vegetation can offset energy-related CO2 emissions, and how effective it is to achieve regional carbon neutrality through vegetation carbon sinks. To clarify the offsetting effect of vegetation carbon sink on energy carbon emissions and support the promotion of achieving the goal of carbon neutrality, we selected the Yangtze River basin (YRB) as the research area, and explored the spatial distribution and service coverage of vegetation-energy carbon balance (VECB) in the basin at the grid scale. We also analyzed the ability of vegetation to maintain carbon balance within the basin, and estimated spatial distribution of energy carbon emissions by using nighttime light images and panel data model. Spatial distribution of vegetation carbon sequestration was calculated by using net primary productivity (NPP) and the Intelligent Urban Ecosystem Management System (IUEMS). Finally, the ability of vegetation to maintain carbon balance was quantified by introducing gas diffusion coefficient. Results showed that, on the whole, energy carbon emissions in YRB are distributed along the main Yangtze River and its main tributaries. Vegetation carbon sink in YRB mainly circulates around the Sichuan Basin and aggregates in the Yunnan-Guizhou Plateau. From 2000 to 2019, VECB in 58% of the basin increased. In 85% of the basin, CO2 generated by energy consumption can be completely offset by vegetation carbon sinks alone. In 2000, 2010 and 2019, the average offset ratio of vegetation to energy carbon emissions in the carbon imbalance region was 51.8%, 40.5% and 39.7%, respectively. The ability of vegetation to maintain carbon balance in YRB decreased gradually from 2000 to 2019. Spatial service range of VECB in YRB decreased gradually in space, with a decrease of 175.22 km from 2000 to 2010 and 22.93 km from 2010 to 2019. [ABSTRACT FROM AUTHOR]