Landfilling is one of the most effective and responsible ways to dispose of municipal solid waste(MSW).Identifying landfill sites,however,is a challenging and complex undertaking because it depends on social,environme...Landfilling is one of the most effective and responsible ways to dispose of municipal solid waste(MSW).Identifying landfill sites,however,is a challenging and complex undertaking because it depends on social,environmental,technical,economic,and legal issues.This study aims to map the optimal sites that were environmentally suitable for locating a landfill site in Butuan City,Philippines.With reference to the policy requirements from DENR Section I,Landfill Site Identification Criteria and Screening Guidelines of National Solid Waste Management Commission,the integration of a Geographic Information System(GIS)model builder and Analytical Hierarchy Process(AHP)has been used in this study to address the aforementioned challenges related to the landfill site suitability analysis.Based on the generated sanitary landfill suitability map,results showed that Barangay Tungao(1131.42967 ha)and Florida(518.48 ha)were able to meet and consider the three(3)main components,namely economic,environmental,and physical criteria,and are highly suitable as landfill site locations in Butuan City.It is recommended that there will conduct a geotechnical evaluation,involving rigorous geological and hydrogeological assessment employing a combination of site investigation and laboratory techniques.In addition,additional specific social,ecological,climatic,and economic factors need to be considered(i.e.including impact on humans,flora,fauna,soil,water,air,climate,and landscape).展开更多
In the United Republic of Tanzania (URT), all environmental issues related to the mining industry are regulated according to two principle Acts: The Mining Act and the Environmental Management Act, and their respectiv...In the United Republic of Tanzania (URT), all environmental issues related to the mining industry are regulated according to two principle Acts: The Mining Act and the Environmental Management Act, and their respective regulations. The current acts were enacted in 2010 and 2004 respectively. Mineral exploration (that includes all on-site activities performed before a mining project is declared feasible) projects in URT appears to be “unforgotten phenomena” in the two major legislative documents, when it comes to environmental considerations. This phenomenon is believed to be causing detrimental effects to the environment. This paper, therefore, analyzes the current environmental regulatory framework on mineral exploration projects in URT and discusses few examples in which mineral exploration projects have caused damage to the indigenous environment. Furthermore, this study reviews environmental regulatory frameworks from other few countries in comparison with existing environmental regulatory framework prevailing in URT.展开更多
This research paper presented the potential of Corchuros olitorius L.as a natural coagulant in the removal of turbidity,total suspended solids,and biochemical oxygen demand from the domestic wastewater of the Universi...This research paper presented the potential of Corchuros olitorius L.as a natural coagulant in the removal of turbidity,total suspended solids,and biochemical oxygen demand from the domestic wastewater of the University of Science and Technology of Southern Philippines.Optimization of the natural coagulant and synthetic coagulant was employed prior to the treatment design.The jar test method was used in the optimization and lab analysis including the gravimetric method,dilution technique,and digital measurements.The optimization results of Corchuros olitorius L.using the jar test method revealed better removal at a lower dosage of 50 mg/L and a higher settling time of 90 minutes.The characterization using FTIR analysis also suggests a functional group that influences coagulation activity.Using the optimum dose and optimum settling time,results with the different treatment designs showed the highest removal at pH 7 showed%BOD removal of 89.78%(A75C25);85.98%(A25C75);88.76%(A50C50).TSS removal measured values of 88.50%(A75C25),85.56%(A25C75),and 87.16%(A50C50),while turbidity removal of 83.47%(A75C25),80.27%(A25C75),and 80.27%(A50C50).Statistically,measured values differ between treatment designs.It is suggested to investigate removal efficiency in more varied pH conditions,different settling times,stirring speed,and other variables for future studies.展开更多
In order to verify the effectiveness of electrolytic treatment on ships’ ballast water, experiments are carried out by a pilot system in laboratory. The raw seawater and seawater with different concentrations of diff...In order to verify the effectiveness of electrolytic treatment on ships’ ballast water, experiments are carried out by a pilot system in laboratory. The raw seawater and seawater with different concentrations of different algae are simulated as ships’ ballast water. The algae in the raw seawater can be killed if it is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L. If the seawater with one kind of algae (Nitzschia closterum, Dicrateria spp., or Pyramidomonnas sp.105cells/mL) is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L, the alga can be sterilized. If the seawater with one kind of algae (Dunaliella sp., Platymonas or Chlorella spp.) is directly treated by electrolyzing with an initial residual chlorine concentration of 4 mg/L, the instant mortality changes with the concentration of different algae. However, after 72 hours, in all treated samples, there are no live algal cells found.展开更多
Soil phosphomonoesterase plays a critical role in controlling phosphorus(P) cycling for crop nutrition,especially in P-deficient soils.A 6-year field experiment was conducted to evaluate soil phosphomonoesterase activ...Soil phosphomonoesterase plays a critical role in controlling phosphorus(P) cycling for crop nutrition,especially in P-deficient soils.A 6-year field experiment was conducted to evaluate soil phosphomonoesterase activities,kinetics and thermodynamics during rice growth stages after consistent swine manure application,to understand the impacts of swine manure amendment rates on soil chemical and enzymatic properties,and to investigate the correlations between soil enzymatic and chemical variables.The experiment was set out in a randomized complete block design with three replicates and five treatments including three swine manure rates(26,39,and 52 kg P ha^(-1),representing low,middle,and high application rates,respectively) and two controls(no-fertilizer and superphosphate at 26 kg P ha^(-1)).The results indicated that the grain yield and soil chemical properties were significantly improved with the application of P-based swine manure from 0 to 39 kg P ha^(-1);however,the differences between the 39(M_(39)) and 52 kg P ha^(-1) treatments(M_(52)) were not significant.The enzymatic property analysis indicated that acid phosphomonoesterase was the predominant phosphomonoesterase in the tested soil.The M_(39) and M_(52) treatments had relatively high initial velocity(V_0),maximal velocity(V_(max)),and activation grade(lgN_a) but low Michaelis constant(K_m),temperature coefficient(Q_(10)),activation energy(E_a),and activation enthalpy(ΔH),implying that the M_(39) and M_(52) treatments could stimulate the enzyme-catalyzed reactions more easily than all other treatments.The correlation analysis showed that the distribution of soil phosphomonoesterase activities mainly followed the distributions of total C and total N.Based on these results,39 kg P ha^(-1) could be recommended as the most appropriate rate of swine manure amendment.展开更多
The combination of two bacteria (Bacillus sp. PY1 and Sphingomonas sp. PY2) and a fungus (Fusarium sp. PY3), isolated from contaminated soils near a coking plant, were investigated with respect to their capability...The combination of two bacteria (Bacillus sp. PY1 and Sphingomonas sp. PY2) and a fungus (Fusarium sp. PY3), isolated from contaminated soils near a coking plant, were investigated with respect to their capability to degrade pyrene and volatilize arsenic. The results showed that all strains could use pyrene and arsenic as carbon and energy sources in a basal salts medium (BSM), with the combined potential to degrade pyrene and volatilize arsenic. Bacillus sp. PY1, Sphingomonas sp. PY2 and Fusarium sp. PY3 were isolated from the consortium and were shown to degrade pyrene and volatilize arsenic independently and in combination. Fungal-bacterial cocul- ture has shown that the most effective removal of pyrene was 96.0% and volatilized arsenic was 84.1% after incubation in liquid medium after 9 days culture, while bioremediation ability was 87.2% in contaminated soil with 100 mg-kg-1 pyrene. The highest level of arsenic volatilization amounted to 13.9% of the initial As concentration in contaminated soil after 63 days. There- fore, a synergistic degradation system is the most effective approach to degrade pyrene and remove arsenic in contaminated soil. These findings highlight the role of these strains in the bioremediation of environments contaminated with pyrene and arsenic.展开更多
This study was designed to evaluate whether the decentralized rural kitchen waste(KW)composting technologies used in China can be widely applied.To this end,we completed a techno-economic analysis of three typical typ...This study was designed to evaluate whether the decentralized rural kitchen waste(KW)composting technologies used in China can be widely applied.To this end,we completed a techno-economic analysis of three typical types of KW compositing,namely solar-assisted(SAC),bio-enhanced(BEC),and heat-dewatering composting(HDC).These evaluations revealed that all three technologies produce composting products that meet China’s organic fertilizer standard and that both SAC and BEC are economically self-sustaining and generate net profits(18824.94 and 17791.52 US$/a)and positive net present values(32133.11 and 25035.93 US$).Subsequent sensitivity analysis demonstrated that the KW-handling subsidy plays a critical role in making decentralized composting economically attractive.Based on these analyses,we believe that reducing the coverage area of SAC,reducing the operating cost of BEC and HDC,upgrading composting products,and strengthening secondary pollution control would aid in supporting the technological improvement of these processes.Moreover,providing appropriate subsidies and promulgating specific standards and policies for KW fertilizer are key strategies for decentralized rural KW composting management.展开更多
Biochar has been reported to mitigate short-term methane(CH4)emissions from paddy soil.Currently,CH4 mitigation by biochar has primarily focused on the abundance and variations of methanogens and methanotrophs,and cha...Biochar has been reported to mitigate short-term methane(CH4)emissions from paddy soil.Currently,CH4 mitigation by biochar has primarily focused on the abundance and variations of methanogens and methanotrophs,and changes in their activities during methane production and consumption.However,long-term effects of biochar on methane mitigation from paddy soil remain controversial.This review overviewed the existing mechanisms for CH4 mitigation as a result of biochar application.In addition,the two existing opinions on the long-term CH4 mitigation effect upon biochar application were highlighted.Combining the already explored mechanisms of fresh biochar on CH4 mitigation from paddy soil and a novel discovery,the potential mechanisms of biochar on long-term methane emission response were proposed.This review also revealed the uncertain responses of biochar on long-term CH4 mitigation.Therefore,to achieve carbon neutral goal,it is important to further explore the mechanisms of long-term CH4 mitigation under biochar application.展开更多
Field experiments provide an opportunity to study the effects of fertilization on soil organic carbon(SOC) sequestration.We sampled soils from a long-term(25 years) paddy experiment in subtropical China.The experiment...Field experiments provide an opportunity to study the effects of fertilization on soil organic carbon(SOC) sequestration.We sampled soils from a long-term(25 years) paddy experiment in subtropical China.The experiment included eight treatments:(1) check,(2) PK,(3) NP,(4) NK,(5) NPK,(6) 7F:3M(N,P,K inorganic fertilizers+30% organic N),(7) 5F:5M(N,P,K inorganic fertilizers+50% organic N),(8) 3F:7M(N,P,K inorganic fertilizers+70% or-ganic N).Fertilization increased SOC content in the plow layers compared to the non-fertilized check treatment.The SOC density in the top 100 cm of soil ranged from 73.12 to 91.36 Mg/ha.The SOC densities of all fertilizer treatments were greater than that of the check.Those treatments that combined inorganic fertilizers and organic amendments had greater SOC densities than those receiving only inorganic fertilizers.The SOC density was closely correlated to the sum of the soil carbon converted from organic amendments and rice residues.Carbon sequestration in paddy soils could be achieved by balanced and combined fertilization.Fertilization combining both inorganic fertilizers and organic amendments is an effective sustainable practice to sequestrate SOC.展开更多
Herein,we use an oxidation flow reactor,Gothenburg:Potential Aerosol Mass(Go:PAM)reactor,to investigate the secondary organic aerosol(SOA)formation from wheat straw burning.Biomass burning emissions are exposed to hig...Herein,we use an oxidation flow reactor,Gothenburg:Potential Aerosol Mass(Go:PAM)reactor,to investigate the secondary organic aerosol(SOA)formation from wheat straw burning.Biomass burning emissions are exposed to high concentrations of hydroxyl radicals(OH)to simulate processes equivalent to atmospheric oxidation of 0-2.55 days.Primary volatile organic compounds(VOCs)were investigated,and particles were measured before and after the Go:PAM reactor.The influence of water content(i.e.5%and 11%)in wheat straw was also explored.Two burning stages,the flaming stage,and non-flaming stages,were identified.Primary particle emission factors(EFs)at a water content of 11%(~3.89 g/kg-fuel)are significantly higher than those at a water content of 5%(~2.26 g/kg-fuel)during the flaming stage.However,the water content showed no significant influence at the non-flaming stage.EFs of aromatics at a non-flaming stage(321.8±46.2 mg/kg-fuel)are larger than that at a flaming stage(130.9±37.1 mg/kg-fuel).The OA enhancement ratios increased with the increase in OH exposure at first and decreased with the additional increment of OH exposure.The maximum OA enhancement ratio is~12 during the non-flaming stages,which is much higher than~1.7 during the flaming stages.The mass spectrum of the primary wheat burning organic aerosols closely resembles that of resolved biomass burning organic aerosols(BBOA)based on measurements in ambient air.Our results show that large gap(0%-90%)still remains to estimate biomass burning SOA if only the oxidation of VOCs were included.展开更多
文摘Landfilling is one of the most effective and responsible ways to dispose of municipal solid waste(MSW).Identifying landfill sites,however,is a challenging and complex undertaking because it depends on social,environmental,technical,economic,and legal issues.This study aims to map the optimal sites that were environmentally suitable for locating a landfill site in Butuan City,Philippines.With reference to the policy requirements from DENR Section I,Landfill Site Identification Criteria and Screening Guidelines of National Solid Waste Management Commission,the integration of a Geographic Information System(GIS)model builder and Analytical Hierarchy Process(AHP)has been used in this study to address the aforementioned challenges related to the landfill site suitability analysis.Based on the generated sanitary landfill suitability map,results showed that Barangay Tungao(1131.42967 ha)and Florida(518.48 ha)were able to meet and consider the three(3)main components,namely economic,environmental,and physical criteria,and are highly suitable as landfill site locations in Butuan City.It is recommended that there will conduct a geotechnical evaluation,involving rigorous geological and hydrogeological assessment employing a combination of site investigation and laboratory techniques.In addition,additional specific social,ecological,climatic,and economic factors need to be considered(i.e.including impact on humans,flora,fauna,soil,water,air,climate,and landscape).
文摘In the United Republic of Tanzania (URT), all environmental issues related to the mining industry are regulated according to two principle Acts: The Mining Act and the Environmental Management Act, and their respective regulations. The current acts were enacted in 2010 and 2004 respectively. Mineral exploration (that includes all on-site activities performed before a mining project is declared feasible) projects in URT appears to be “unforgotten phenomena” in the two major legislative documents, when it comes to environmental considerations. This phenomenon is believed to be causing detrimental effects to the environment. This paper, therefore, analyzes the current environmental regulatory framework on mineral exploration projects in URT and discusses few examples in which mineral exploration projects have caused damage to the indigenous environment. Furthermore, this study reviews environmental regulatory frameworks from other few countries in comparison with existing environmental regulatory framework prevailing in URT.
文摘This research paper presented the potential of Corchuros olitorius L.as a natural coagulant in the removal of turbidity,total suspended solids,and biochemical oxygen demand from the domestic wastewater of the University of Science and Technology of Southern Philippines.Optimization of the natural coagulant and synthetic coagulant was employed prior to the treatment design.The jar test method was used in the optimization and lab analysis including the gravimetric method,dilution technique,and digital measurements.The optimization results of Corchuros olitorius L.using the jar test method revealed better removal at a lower dosage of 50 mg/L and a higher settling time of 90 minutes.The characterization using FTIR analysis also suggests a functional group that influences coagulation activity.Using the optimum dose and optimum settling time,results with the different treatment designs showed the highest removal at pH 7 showed%BOD removal of 89.78%(A75C25);85.98%(A25C75);88.76%(A50C50).TSS removal measured values of 88.50%(A75C25),85.56%(A25C75),and 87.16%(A50C50),while turbidity removal of 83.47%(A75C25),80.27%(A25C75),and 80.27%(A50C50).Statistically,measured values differ between treatment designs.It is suggested to investigate removal efficiency in more varied pH conditions,different settling times,stirring speed,and other variables for future studies.
文摘In order to verify the effectiveness of electrolytic treatment on ships’ ballast water, experiments are carried out by a pilot system in laboratory. The raw seawater and seawater with different concentrations of different algae are simulated as ships’ ballast water. The algae in the raw seawater can be killed if it is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L. If the seawater with one kind of algae (Nitzschia closterum, Dicrateria spp., or Pyramidomonnas sp.105cells/mL) is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L, the alga can be sterilized. If the seawater with one kind of algae (Dunaliella sp., Platymonas or Chlorella spp.) is directly treated by electrolyzing with an initial residual chlorine concentration of 4 mg/L, the instant mortality changes with the concentration of different algae. However, after 72 hours, in all treated samples, there are no live algal cells found.
基金supported by the National Natural Science Foundation of China(Nos.21077088,41271314and 51008107)
文摘Soil phosphomonoesterase plays a critical role in controlling phosphorus(P) cycling for crop nutrition,especially in P-deficient soils.A 6-year field experiment was conducted to evaluate soil phosphomonoesterase activities,kinetics and thermodynamics during rice growth stages after consistent swine manure application,to understand the impacts of swine manure amendment rates on soil chemical and enzymatic properties,and to investigate the correlations between soil enzymatic and chemical variables.The experiment was set out in a randomized complete block design with three replicates and five treatments including three swine manure rates(26,39,and 52 kg P ha^(-1),representing low,middle,and high application rates,respectively) and two controls(no-fertilizer and superphosphate at 26 kg P ha^(-1)).The results indicated that the grain yield and soil chemical properties were significantly improved with the application of P-based swine manure from 0 to 39 kg P ha^(-1);however,the differences between the 39(M_(39)) and 52 kg P ha^(-1) treatments(M_(52)) were not significant.The enzymatic property analysis indicated that acid phosphomonoesterase was the predominant phosphomonoesterase in the tested soil.The M_(39) and M_(52) treatments had relatively high initial velocity(V_0),maximal velocity(V_(max)),and activation grade(lgN_a) but low Michaelis constant(K_m),temperature coefficient(Q_(10)),activation energy(E_a),and activation enthalpy(ΔH),implying that the M_(39) and M_(52) treatments could stimulate the enzyme-catalyzed reactions more easily than all other treatments.The correlation analysis showed that the distribution of soil phosphomonoesterase activities mainly followed the distributions of total C and total N.Based on these results,39 kg P ha^(-1) could be recommended as the most appropriate rate of swine manure amendment.
文摘The combination of two bacteria (Bacillus sp. PY1 and Sphingomonas sp. PY2) and a fungus (Fusarium sp. PY3), isolated from contaminated soils near a coking plant, were investigated with respect to their capability to degrade pyrene and volatilize arsenic. The results showed that all strains could use pyrene and arsenic as carbon and energy sources in a basal salts medium (BSM), with the combined potential to degrade pyrene and volatilize arsenic. Bacillus sp. PY1, Sphingomonas sp. PY2 and Fusarium sp. PY3 were isolated from the consortium and were shown to degrade pyrene and volatilize arsenic independently and in combination. Fungal-bacterial cocul- ture has shown that the most effective removal of pyrene was 96.0% and volatilized arsenic was 84.1% after incubation in liquid medium after 9 days culture, while bioremediation ability was 87.2% in contaminated soil with 100 mg-kg-1 pyrene. The highest level of arsenic volatilization amounted to 13.9% of the initial As concentration in contaminated soil after 63 days. There- fore, a synergistic degradation system is the most effective approach to degrade pyrene and remove arsenic in contaminated soil. These findings highlight the role of these strains in the bioremediation of environments contaminated with pyrene and arsenic.
基金This work was financially supported by the Zhejiang Province Key Research and Development Project(Nos.2019C03006 and 2021C03024).
文摘This study was designed to evaluate whether the decentralized rural kitchen waste(KW)composting technologies used in China can be widely applied.To this end,we completed a techno-economic analysis of three typical types of KW compositing,namely solar-assisted(SAC),bio-enhanced(BEC),and heat-dewatering composting(HDC).These evaluations revealed that all three technologies produce composting products that meet China’s organic fertilizer standard and that both SAC and BEC are economically self-sustaining and generate net profits(18824.94 and 17791.52 US$/a)and positive net present values(32133.11 and 25035.93 US$).Subsequent sensitivity analysis demonstrated that the KW-handling subsidy plays a critical role in making decentralized composting economically attractive.Based on these analyses,we believe that reducing the coverage area of SAC,reducing the operating cost of BEC and HDC,upgrading composting products,and strengthening secondary pollution control would aid in supporting the technological improvement of these processes.Moreover,providing appropriate subsidies and promulgating specific standards and policies for KW fertilizer are key strategies for decentralized rural KW composting management.
基金supported by National Natural Science Foundation of China[Grant numbers 42077032 and 41571241]the National Key Technology Research and Development Program of the Ministry of Science and Technology of China[Grant number 2015BAC02B01]We thank the editors and reviewers for their constructive comments.
文摘Biochar has been reported to mitigate short-term methane(CH4)emissions from paddy soil.Currently,CH4 mitigation by biochar has primarily focused on the abundance and variations of methanogens and methanotrophs,and changes in their activities during methane production and consumption.However,long-term effects of biochar on methane mitigation from paddy soil remain controversial.This review overviewed the existing mechanisms for CH4 mitigation as a result of biochar application.In addition,the two existing opinions on the long-term CH4 mitigation effect upon biochar application were highlighted.Combining the already explored mechanisms of fresh biochar on CH4 mitigation from paddy soil and a novel discovery,the potential mechanisms of biochar on long-term methane emission response were proposed.This review also revealed the uncertain responses of biochar on long-term CH4 mitigation.Therefore,to achieve carbon neutral goal,it is important to further explore the mechanisms of long-term CH4 mitigation under biochar application.
基金Project supported by the Special Fund for Agro-scientific Research in the Public Interest (No. 201003059)the National Natural Science Foundation of China (Nos. 21077088,40901142,51008107,and 31000296)+1 种基金the National Key Science and Technology Special Projects of Water Body Pollution Control and Management (Nos.2008ZX 07101-006 and 2008ZX 07528-005-003)the National Science and Technology Support Program of China (No.2011BAD41B01)
文摘Field experiments provide an opportunity to study the effects of fertilization on soil organic carbon(SOC) sequestration.We sampled soils from a long-term(25 years) paddy experiment in subtropical China.The experiment included eight treatments:(1) check,(2) PK,(3) NP,(4) NK,(5) NPK,(6) 7F:3M(N,P,K inorganic fertilizers+30% organic N),(7) 5F:5M(N,P,K inorganic fertilizers+50% organic N),(8) 3F:7M(N,P,K inorganic fertilizers+70% or-ganic N).Fertilization increased SOC content in the plow layers compared to the non-fertilized check treatment.The SOC density in the top 100 cm of soil ranged from 73.12 to 91.36 Mg/ha.The SOC densities of all fertilizer treatments were greater than that of the check.Those treatments that combined inorganic fertilizers and organic amendments had greater SOC densities than those receiving only inorganic fertilizers.The SOC density was closely correlated to the sum of the soil carbon converted from organic amendments and rice residues.Carbon sequestration in paddy soils could be achieved by balanced and combined fertilization.Fertilization combining both inorganic fertilizers and organic amendments is an effective sustainable practice to sequestrate SOC.
基金supported by National Natural Science Foundation of China(Nos.51636003,91844301,41977179)Beijing Municipal Science and Technology Commission(No.Z201100008220011)+2 种基金Natural Science Foundation of Beijing(No.8192022)China Postdoctoral Science Foundation(No.2020M680242)the Open Research Fund of State Key Laboratory of Multi-phase Complex Systems(No.MPCS-2021-D-12)
文摘Herein,we use an oxidation flow reactor,Gothenburg:Potential Aerosol Mass(Go:PAM)reactor,to investigate the secondary organic aerosol(SOA)formation from wheat straw burning.Biomass burning emissions are exposed to high concentrations of hydroxyl radicals(OH)to simulate processes equivalent to atmospheric oxidation of 0-2.55 days.Primary volatile organic compounds(VOCs)were investigated,and particles were measured before and after the Go:PAM reactor.The influence of water content(i.e.5%and 11%)in wheat straw was also explored.Two burning stages,the flaming stage,and non-flaming stages,were identified.Primary particle emission factors(EFs)at a water content of 11%(~3.89 g/kg-fuel)are significantly higher than those at a water content of 5%(~2.26 g/kg-fuel)during the flaming stage.However,the water content showed no significant influence at the non-flaming stage.EFs of aromatics at a non-flaming stage(321.8±46.2 mg/kg-fuel)are larger than that at a flaming stage(130.9±37.1 mg/kg-fuel).The OA enhancement ratios increased with the increase in OH exposure at first and decreased with the additional increment of OH exposure.The maximum OA enhancement ratio is~12 during the non-flaming stages,which is much higher than~1.7 during the flaming stages.The mass spectrum of the primary wheat burning organic aerosols closely resembles that of resolved biomass burning organic aerosols(BBOA)based on measurements in ambient air.Our results show that large gap(0%-90%)still remains to estimate biomass burning SOA if only the oxidation of VOCs were included.