Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing techniques.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their Soft X-ray Imager(SXI)instruments.While earlier modeling works have already simulated soft X-ray images as might be obtained by SMILE SXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space plasma.To investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator model.The simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic field.We first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial views.We then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the magnetopause.Our results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the SMILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray images.For instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this region.Likewise,a proton density increase by 14%in the magnetosheath associated with mirror-mode structures can result in an enhancement in the soft X-ray signal by 4%.These are likely conservative estimates,given that the solar wind conditions used in the Vlasiator run can be expected to generate weaker soft X-ray emissions than the more common denser solar wind.These results will contribute to the preparatory work for the SMILE and LEXI missions by providing the community with quantitative estimates of the effects of small-scale,transient phenomena occurring on the dayside.

Repositioning fertilizer manufacturing subsidies for improving food security and reducing greenhouse gas emissions in China

China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable practices.However,the impact of this policy reform on food security and the environment remains inadequately evaluated.Moreover,although green and low-carbon technologies offer environmental advantages,their widespread adoption is hindered by prohibitively high costs.This study analyzes the impact of removing fertilizer manufacturing subsidies and explores the potential feasibility of redirecting fertilizer manufacturing subsidies to invest in the diffusion of these technologies.Utilizing the China Agricultural University Agri-food Systems model,we analyzed the potential for achieving mutually beneficial outcomes regarding food security and environmental sustainability.The findings indicate that removing fertilizer manufacturing subsidies has reduced greenhouse gas(GHG)emissions from agricultural activities by 3.88 million metric tons,with minimal impact on food production.Redirecting fertilizer manufacturing subsidies to invest in green and low-carbon technologies,including slow and controlled-release fertilizer,organic-inorganic compound fertilizers,and machine deep placement of fertilizer,emerges as a strategy to concurrently curtail GHG emissions,ensure food security,and secure robust economic returns.Finally,we propose a comprehensive set of government interventions,including subsidies,field guidance,and improved extension systems,to promote the widespread adoption of these technologies.

Effect of speed humps on instantaneous traffic emissions in a microscopic model with limited deceleration capacity

As a common transportation facility, speed humps can control the speed of vehicles on special road sections to reduce traffic risks. At the same time, they also cause instantaneous traffic emissions. Based on the classic instantaneous traffic emission model and the limited deceleration capacity microscopic traffic flow model with slow-to-start rules, this paper has investigated the impact of speed humps on traffic flow and the instantaneous emissions of vehicle pollutants in a single lane situation. The numerical simulation results have shown that speed humps have significant effects on traffic flow and traffic emissions. In a free-flow region, the increase of speed humps leads to the continuous rise of CO_(2), NO_(X) and PM emissions. Within some density ranges, one finds that these pollutant emissions can evolve into some higher values under some random seeds. Under other random seeds, they can evolve into some lower values. In a wide moving jam region, the emission values of these pollutants sometimes appear as continuous or intermittent phenomenon. Compared to the refined Na Sch model, the present model has lower instantaneous emissions such as CO_(2), NO_(X) and PM and higher volatile organic components(VOC) emissions. Compared to the limited deceleration capacity model without slow-to-start rules, the present model also has lower instantaneous emissions such as CO_(2), NO_(X) and PM and higher VOC emissions in a wide moving jam region. These results can also be confirmed or explained by the statistical values of vehicle velocity and acceleration.

Effect of rice cultivar on greenhouse-gas emissions from rice-fish co-culture

In aquaculture,co-culturing rice with fish may mitigate greenhouse-gas emissions.In this study,co-culture of four rice cultivars in a laboratory-scale rice–fish system reduced CH_(4)and N_(2)O emissions relative to fish monoculture.Differences in CH_(4)and N_(2)O emissions among rice cultivars primarily stem from the differential effects of rice plants on plant-mediated CH_(4)transport,CH_(4)oxidation and nitrogen absorption.

A combination of straw incorporation and polymer-coated urea offsets soil ammonia and nitrous oxide emissions in winter wheat fields

The combined effects of straw incorporation(SI)and polymer-coated urea(PCU)application on soil ammonia(NH_(3))and nitrous oxide(N_(2)O)emissions from agricultural fields have not been comprehensively evaluated in Northwest China.We conducted a two-year field experiment to assess the effects of combining SI with either uncoated urea(U)or PCU on soil NH_(3)emissions,N_(2)O emissions,winter wheat yields,yield-scaled NH_(3)(/NH_(3)),and yield-scaled N_(2)O(/N_(2)O).Five treatments were investigated,no nitrogen(N)fertilizer(N_(0)),U application at 150 kg N ha-1 with and without SI(SI+U and S_(0)+U),and PCU application at 150 kg N ha^(-1) with and without SI(SI+PCU and S_(0)+PCU).The results showed that the NH_(3);emissions increased by 20.98-34.35%following Sl compared to straw removal,mainly due to increases in soil ammonium(NH_(4)^(+)-N)content and water-flled pore space(WFPS).SI resulted in higher N_(2)O emissions than under the So scenario by 13.31-49.23%due to increases in soil inorganic N(SIN)contents,WFPS,and soil microbial biomass.In contrast,the PCU application reduced the SIN contents compared to the U application,reducing the NH_(3)and N_(2)O emissions by 45.99-58.07 and 18.08-53.04%,respectively.Moreover,no significant positive effects of the SI or PCU applications on the winter wheat yield were observed.The lowest /NH_(3) and /N_(2)O values were observed under the S_(0)+PCU and SI+PCU treatments.Our results suggest that single PCU applications and their combination with straw are the optimal agricultural strategies for mitigating gaseous N emissions and maintaining optimal winter wheat yields in Northwest China.

Mitigating Carbon Emissions:A Comprehensive Analysis of Transitioning to Hydrogen-Powered Plants in Japan’s Energy Landscape Post-Fukushima

One of the impacts of the Fukushima disaster was the shutdown of all nuclear power plants in Japan,reaching zero production in 2015.In response,the country started importing more fossil energy including coal,oil,and natural gas to fill the energy gap.However,this led to a significant increase in carbon emissions,hindering the efforts to reduce its carbon footprint.In the current situation,Japan is actively working to balance its energy requirements with environmental considerations,including the utilization of hydrogen fuel.Therefore,this paper aims to explore the feasibility and implications of using hydrogen power plants as a means to reduce emissions,and this analysis will be conducted using the energy modeling of the MARKAL-TIMES Japan framework.The hydrogen scenario(HS)is assumed with the extensive integration of hydrogen into the power generation sector,supported by a hydrogen import scheme.Additionally,this scenario will be compared with the Business as Usual(BAU)scenario.The results showed that the generation capacities of the BAU and HS scenarios have significantly different primary energy supplies.The BAU scenario is highly dependent on fossil fuels,while the HS scenario integrates hydrogen contribution along with an increase in renewable energy,reaching a peak contribution of 2,160 PJ in 2050.In the HS scenario,the target of reducing CO_(2) emissions by 80%is achieved through significant hydrogen penetration.By 2050,the total CO_(2) emissions are estimated to be 939 million tons for the BAU scenario and 261 million tons for the Hydrogen scenario.In addition,the contribution of hydrogen to electricity generation is expected to be 153 TWh,smaller than PV and wind power.

Spatiotemporal Differentiation of Urban Spatial Form and Carbon Emissions in Poyang Lake City Group

In response to the inherent requirements of low-carbon land spatial planning in Jiangxi Province and the lack of existing research,this paper explored the mechanism of spatial form elements of Poyang Lake urban agglomeration on urban carbon emissions.Based on generalized linear regression and geographically weighted regression models,this paper analyzed the spatiotemporal distribution characteristics of carbon emissions,the spatiotemporal relationship between urban form index and carbon emissions,and the spatial differentiation of the intensity of dominant factors from 63 county-level administrative units in the Poyang Lake city group from 2005 to 2020.The results showed that:①The carbon emissions of urban agglomerations around Poyang Lake are generally increasing,and the spatial distribution of carbon emissions is characterized by high-value concentration in the middle and low-value agglomeration in pieces;②The main driving factor for the spatial heterogeneity of carbon emissions was the expansion of built-up area;③Improving urban compactness and optimizing urban form could effectively reduce urban carbon emissions.The results showcased the correlation between urban spatial landscape pattern and the spatiotemporal distribution of carbon emissions,which could make the low-carbon land spatial planning in the Poyang Lake city group more reasonable and practical.

Global hybrid simulations of soft X-ray emissions in the Earth’s magnetosheath

Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a satellite.By performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of Earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic field.In all cases,magnetic reconnection occurs at low latitude magnetopause.The soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the magnetosheath.Local X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray images.Moreover,the magnetopause boundary can be identified using multiple viewing geometries.We also find that solar wind conditions have little effect on the magnetopause identification.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered.

Prospects for green steelmaking technology with low carbon emissions in China

The steel industry is a major source of CO_(2) emissions,and thus,the mitigation of carbon emissions is the most pressing challenge in this sector.In this paper,international environmental governance in the steel industry is reviewed,and the current state of development of low-carbon technologies is discussed.Additionally,low-carbon pathways for the steel industry at the current time are proposed,emphasizing prevention and treatment strategies.Furthermore,the prospects of low-carbon technologies are explored from the perspective of transitioning the energy structure to a“carbon-electricity-hydrogen”relationship.Overall,steel enterprises should adopt hydrogen-rich metallurgical technologies that are compatible with current needs and process flows in the short term,based on the carbon substitution with hydrogen(prevention)and the CCU(CO_(2) capture and utilization)concepts(treatment).Additionally,the capture and utilization of CO_(2) for steelmaking,which can assist in achieving short-term emission reduction targets but is not a long-term solution,is discussed.In conclusion,in the long term,the carbon metallurgical process should be gradually supplanted by a hydrogen-electric synergistic approach,thus transforming the energy structure of existing steelmaking processes and attaining near-zero carbon emission steelmaking technology.

Regulatory potential of soil available carbon,nitrogen,and functional genes on N_(2)O emissions in two upland plantation systems

Dynamic nitrification and denitrification processes are affected by changes in soil redox conditions,and they play a vital role in regulating soil N_(2)O emissions in rice-based cultivation.It is imperative to understand the influences of different upland crop planting systems on soil N_(2)O emissions.In this study,we focused on two representative rotation systems in Central China:rapeseed–rice(RR)and wheat–rice(WR).We examined the biotic and abiotic processes underlying the impacts of these upland plantings on soil N_(2)O emissions.The results revealed that during the rapeseed-cultivated seasons in the RR rotation system,the average N_(2)O emissions were 1.24±0.20 and 0.81±0.11 kg N ha^(–1)for the first and second seasons,respectively.These values were comparable to the N_(2)O emissions observed during the first and second wheat-cultivated seasons in the WR rotation system(0.98±0.25 and 0.70±0.04 kg N ha^(–1),respectively).This suggests that upland cultivation has minimal impacts on soil N_(2)O emissions in the two rotation systems.Strong positive correlations were found between N_(2)O fluxes and soil ammonium(NH_(4)^(+)),nitrate(NO_(3)^(–)),microbial biomass nitrogen(MBN),and the ratio of soil dissolved organic carbon(DOC)to NO_(3)^(–)in both RR and WR rotation systems.Moreover,the presence of the AOA-amoA and nirK genes were positively associated with soil N_(2)O fluxes in the RR and WR systems,respectively.This implies that these genes may have different potential roles in facilitating microbial N_(2)O production in various upland plantation models.By using a structural equation model,we found that soil moisture,mineral N,MBN,and the AOA-amoA gene accounted for over 50%of the effects on N_(2)O emissions in the RR rotation system.In the WR rotation system,soil moisture,mineral N,MBN,and the AOA-amoA and nirK genes had a combined impact of over 70%on N_(2)O emissions.These findings demonstrate the interactive effects of functional genes and soil factors,including soil physical characteristics,available carbon and nitrogen,and their ratio,on soil N_(2)O emissions during upland cultivation seasons under rice-upland rotations.

Rolling Decision Model of Thermal Power Retrofit and Generation Expansion Planning Considering Carbon Emissions and Power Balance Risk

With the increasing urgency of the carbon emission reduction task,the generation expansion planning process needs to add carbon emission risk constraints,in addition to considering the level of power adequacy.However,methods for quantifying and assessing carbon emissions and operational risks are lacking.It results in excessive carbon emissions and frequent load-shedding on some days,although meeting annual carbon emission reduction targets.First,in response to the above problems,carbon emission and power balance risk assessment indicators and assessment methods,were proposed to quantify electricity abundance and carbon emission risk level of power planning scenarios,considering power supply regulation and renewable energy fluctuation characteristics.Secondly,building on traditional two-tier models for low-carbon power planning,including investment decisions and operational simulations,considering carbon emissions and power balance risks in lower-tier operational simulations,a two-tier rolling model for thermal power retrofit and generation expansion planning was established.The model includes an investment tier and operation assessment tier and makes year-by-year decisions on the number of thermal power units to be retrofitted and the type and capacity of units to be commissioned.Finally,the rationality and validity of the model were verified through an example analysis,a small-scale power supply system in a certain region is taken as an example.The model can significantly reduce the number of days of carbon emissions risk and ensure that the power balance risk is within the safe limit.

Analysis of Emissions Profiles of Hydraulic Fracturing Engine Technologies

Today, the oil and gas industry, and in particular hydraulic fracturing operations, have come under increasing pressure from regulators and the public to reduce emissions. As the industry evolves, oil and gas producers are in the position of evaluating alternative technologies which will support their objectives of reducing their overall emissions profile and carbon footprint. As a response, the deployment of technology and solutions to reduce emissions related to hydraulic fracturing applications has recently accelerated, creating various options to address these industry challenges. BJ Energy Solutions and West Virginia University have been working on the application and emissions characterization of various hydraulic fracturing technologies. A study was conducted to evaluate the efficiency and resultant emissions from various technologies, including natural gas reciprocating engines, diesel-natural gas dual-fuel engines, large (>24 MW) gas turbines, and direct drive turbines. The study involved the development of an emissions model with the purpose of estimating total emissions of carbon dioxide (CO2), nitrous oxide (N2O) and exhaust methane (CH4) slip, all Greenhouse Gases (GHGs), and converted to tons of CO2 equivalent emissions per day of operation. The model inputs are the required Hydraulic Horsepower (HHP) based on pumping rate and pressure for various shale play scenarios. The model calculates emissions from the TITAN, which is a direct-drive turbine model fielded by BJ, using data collected following U.S. Environmental Protection Agency (EPA) testing protocols. The model also calculates and compares other hydraulic fracturing technologies utilizing published Original Equipment Manufacturer (OEM) data. Relevant EPA-regulated criteria emissions of oxides of nitrogen (NOx), Carbon Monoxide (CO) and Particulate Matter (PM) are also reported. Modeling results demonstrated that in most cases, the TITAN gas turbine system has lower total GHG emissions than conventional diesel and other next-generation technologies, and also has lower criteria emissions. The benefits of the TITAN gas turbine system compared to the other technologies stems from significantly lower methane slip, and the high-power transfer efficiency resulting from directly connecting a turbine to a reciprocating pump, despite the comparatively lower thermal efficiency.

Dietary supplementation with xylooligosaccharides and exogenous enzyme improves milk production,energy utilization efficiency and reduces enteric methane emissions of Jersey cows

Background Sustainable strategies for enteric methane(CH_(4))mitigation of dairy cows have been extensively explored to improve production performance and alleviate environmental pressure.The present study aimed to investigate the effects of dietary xylooligosaccharides(XOS)and exogenous enzyme(EXE)supplementation on milk production,nutrient digestibility,enteric CH_(4) emissions,energy utilization efficiency of lactating Jersey dairy cows.Forty-eight lactating cows were randomly assigned to one of 4 treatments:(1)control diet(CON),(2)CON with 25 g/d XOS(XOS),(3)CON with 15 g/d EXE(EXE),and(4)CON with 25 g/d XOS and 15 g/d EXE(XOS+EXE).The 60-d experimental period consisted of a 14-d adaptation period and a 46-d sampling period.The enteric CO_(2)and CH_(4) emissions and O2 consumption were measured using two GreenFeed units,which were further used to determine the energy utilization efficiency of cows.Results Compared with CON,cows fed XOS,EXE or XOS+EXE significantly(P<0.05)increased milk yield,true protein and fat concentration,and energy-corrected milk yield(ECM)/DM intake,which could be reflected by the significant improvement(P<0.05)of dietary NDF and ADF digestibility.The results showed that dietary supplementation of XOS,EXE or XOS+EXE significantly(P<0.05)reduced CH_(4) emission,CH_(4)/milk yield,and CH_(4)/ECM.Furthermore,cows fed XOS demonstrated highest(P<0.05)metabolizable energy intake,milk energy output but lowest(P<0.05)of CH_(4) energy output and CH_(4) energy output as a proportion of gross energy intake compared with the remaining treatments.Conclusions Dietary supplementary of XOS,EXE or combination of XOS and EXE contributed to the improvement of lactation performance,nutrient digestibility,and energy utilization efficiency,as well as reduction of enteric CH_(4) emissions of lactating Jersey cows.This promising mitigation method may need further research to validate its long-term effect and mode of action for dairy cows.

Current situation of carbon emissions and countermeasures in China's ironmaking industry

The iron and steel industry(ISI) involves high energy consumption and high pollution. ISI in China, a leading country in the ISI,consumed 15% of the country’s total energy and produced more than 50% of the global ISI’s carbon emissions. Therefore, in the context of global low-carbon economy and emission reduction requirements, low-carbon smelting technology in the ISI has attracted increasingly more attention in China. This review summarizes the current status of carbon emissions and energy consumption in China’s ISI and discusses the development status and prospects of low-carbon ironmaking technology. The main route to effectively reducing carbon emissions is to develop a gas-based direct reduction process and replace sintering with pelletizing, both of which focus on developing pelletizing technology. However,the challenge of pelletizing process development is to obtain high-quality iron concentrates. Consequently, the present paper also summarizes the development status of China’s mineral processing technology, including fine-grained mineral processing technology, magnetization roasting technology, and flotation collector application. This paper aims to provide a theoretical basis for the low-carbon development of China’s ISI in terms of a dressing–smelting combination.

Toward inclusive list-making for trade liberalization in environmental goods to reduce carbon emissions

The Asia-Pacific Economic Cooperation(APEC)is contemplating expanding its list of environmental goods(EG)for trade liberalization to fight climate change.In support of doing so,this study proposes that a long list that retains controversies is better for carbon emission reduction than a short common list.This study examines four mechanisms of longer lists:enlarging market scales,enriching product mixes,enhancing product sophistication,and enriching trade patterns.Using China’s emerging EG trade during the 2001-2015 period as a case study,this study compares four EG lists with different EG.The results show that:(1)a longer list reduces carbon emissions from both imports and exports,making domestic regions with different advantages have better chances of improving carbon efficiencies.(2)Product sophistication reduces the emission gap between trading partners,regardless of the length of EG lists.(3)China’s EG exports contribute to carbon reduction in leading regions,while EG imports provide laggard regions with better chances of reducing carbon emissions.These findings provide three implications for future list-making:it is important to(1)seek a long and inclusive list rather than a short common list,(2)shift the focus from environmental end-use to the technological contents of products,and(3)balance the demand of laggard regions to import and the capacity of leading regions to export.

Revisiting the nexus between fiscal decentralization and CO_(2)emissions in South Africa:fresh policy insights

The argument over fiscal decentralization and carbon dioxide emission(CO_(2))reduction has received much attention.However,evidence to back this claim is limited.Economic theory predicts that fiscal decentralization affects environmental quality,but the specifics of this relationship are still up for debate.Some scholars noted that fiscal decentralization might lead to a race to the top,whereas others contended that it would result in a race to the bottom.In light of the current debates in environmental and development economics,this study aims to provide insight into how this relationship may function in South Africa from 1960 to 2020.In contrast to the existing research,the present study uses a novel dynamic autoregressive distributed lag simulation approach to assess the positive and negative changes in fiscal decentralization,scale effect,technique effect,technological innovation,foreign direct investment,energy consumption,industrial growth,and trade openness on CO_(2)emissions.The following are the main findings:(i)Fiscal decentralization had a CO_(2)emission reduction impact in the short and long run,highlighting the presence of the race to the top approach.(ii)Economic growth(as represented by the scale effect)eroded ecological integrity.However,its square(as expressed by technique effect)aided in strengthening ecological protection,validating the environmental Kuznets curve hypothesis.(iii)CO_(2)emissions were driven by energy utilization,trade openness,industrial value-added,and foreign direct investment,whereas technological innovation boosted ecological integrity.Findings suggest that further fiscal decentralization should be undertaken through further devolution of power to local entities,particularly regarding environmental policy issues,to maintain South Africa’s ecological sustainability.South Africa should also establish policies to improve environmental sustainability by strengthening a lower layer of government and clarifying responsibilities at the national and local levels to fulfill the energy-saving functions of fiscal expenditures.

Asymmetric nexus between commercial policies and consumption‑based carbon emissions:new evidence from Pakistan

The current study extends the previous literature by exploring the effects of a newly discovered driver,i.e.,import taxes(as a proxy for commercial policies),on the consumption-based carbon emissions(CCO2e)for 1990Q1-2017Q4.For empirical analysis,several tests and methods,including Augmented Dickey–Fuller unit root test,Zivot–Andrews unit root test,asymmetric cointegration bound testing approach,non-linear ARDL,Wald-test,Granger causality test and wavelet quantile correlation(WQC)method are utilized.Furthermore,NARDL technique estimates reveal that contractionary commercial policy enhances the environmental quality by disrupting the detrimental effects of CCO2e.However,expansionary commercial policy escalates the environmental pollution by boosting the carbon emissions.Also,the exports and the renewable energy improve the ecological quality;however,GDP deteriorates the atmospheric quality by increasing the CCO2e.Besides,WQC method and the trivariate Granger causality test are deployed to confirm the robustness of the results.Based on the findings,some crucial policies are also recommended for sustainable and green development in Pakistan.

Does enterprise digitization reduce carbon emissions? Evidence from China

The digital transformation and expansion of businesses will provide China’s low-carbon economic develop‐ment strategy with fresh impetus in the backdrop of the emerging digital economy and environmentally friendly growth.This article measures the level of enterprise digitization using two methods:the enterprise digitization index and text analysis word frequency statistics.Additionally,carbon emissions are obtained by measuring various types of emissions according to the carbon emission classification range standard.To ac‐count for endogeneity and unobservable variables,relative indicators,such as the rate of increase for company emissions of carbon,are utilized.Using microdata from Chinese listed firms from 2011 to 2021,this study ex‐amines the implications of corporate digitization on enterprise carbon emissions.This study further analyzes the transmission mechanism and investigates the function of green finance in controlling corporate digitiza‐tion and reducing corporate carbon emissions by distinguishing between two types of green patents.Research shows that businesses’carbon emissions are greatly reduced as a consequence of getting digital.Even after performing several robustness and endogeneity tests,the conclusion still remains valid.According to mecha‐nism analysis,which demonstrates that the main strategy for reducing corporate emissions of carbon through the digitalization of enterprises is to promote innovation in green technology.The regulation of green finance in enterprise digitalization will further reduce corporate carbon emissions.According to the analysis of hetero‐geneity,state-owned businesses and those situated in areas with stringent environmental regulations are more significantly impacted by enterprise digitization on corporate carbon emissions.This article discusses the mechanism of promoting corporate carbon emissions through digitalization,expands on relevant research on corporate digitalization,and analyzes the achievable paths of corporate digitalization and low-carbon develop‐ment strategies.

The relationship between fire severity and burning efficiency for estimating wildfire emissions in Mediterranean forests

Forests are exposed to changing climatic conditions reflected by increasing drought and heat waves that increase the risk of wildfire ignition and spread.Climatic variables such as rain and wind as well as vegetation structure,land configuration and forest management practices are all factors that determine the burning potential of wildfires.The assessment of emissions released by vegetation combustion is essential for determining greenhouse gases and air pollutants.The estimation of wildfire-related emissions depends on factors such as the type and fraction of fuel(i.e.,live biomass,ground litter,dead wood)consumed by the fire in a given area,termed the burning efficiency.Most approaches estimate live burning efficiency from optical remote sensing data.This study used a data-driven method to estimate live burning efficiency in a Mediterranean area.Burning severity estimations from Lands at imagery(dNBR),which relate to fuel consumption,and quantitative field data from three national forest inventory data were combined to establish the relationship between burning severity and live burning efficiency.Several proxies explored these relationships based on dNBR interval classes,as well as regres sion models.The correlation results between live burning efficiency and dNBR for conifers(R=0.63)and broad-leaved vegetation(R=0.95)indicated ways for improving emissions estimations.Median estimations by severity class(low,moderate-low,moderate-high,and high)are provided for conifers(0.44-0.81)and broad-leaves(0.64-0.86),and regression models for the live fraction of the tree canopy susceptible to burning(<2 cm,2-7 cm,>7 branches,and leaves).The live burning efficiency values by severity class were higher than previous studies.

Benchmark Dose Assessment for Coke Oven Emissions-Induced Mitochondrial DNA Copy Number Damage Effects

Objective The study aimed to estimate the benchmark dose(BMD)of coke oven emissions(COEs)exposure based on mitochondrial damage with the mitochondrial DNA copy number(mtDNAcn)as a biomarker.Methods A total of 782 subjects were recruited,including 238 controls and 544 exposed workers.The mtDNAcn of peripheral leukocytes was detected through the real-time fluorescence-based quantitative polymerase chain reaction.Three BMD approaches were used to calculate the BMD of COEs exposure based on the mitochondrial damage and its 95%confidence lower limit(BMDL).Results The mtDNAcn of the exposure group was lower than that of the control group(0.60±0.29 vs.1.03±0.31;P<0.001).A dose-response relationship was shown between the mtDNAcn damage and COEs.Using the Benchmark Dose Software,the occupational exposure limits(OELs)for COEs exposure in males was 0.00190 mg/m^(3).The OELs for COEs exposure using the BBMD were 0.00170 mg/m^(3)for the total population,0.00158 mg/m^(3)for males,and 0.00174 mg/m^(3)for females.In possible risk obtained from animal studies(PROAST),the OELs of the total population,males,and females were 0.00184,0.00178,and 0.00192 mg/m^(3),respectively.Conclusion Based on our conservative estimate,the BMDL of mitochondrial damage caused by COEs is0.002 mg/m^(3).This value will provide a benchmark for determining possible OELs.