简介:AftertheKyotoProtocolwasimplemented,carbonleakageexertsgreatinfluencesoninternationaltradeandeconomy.Tradecreatesamechanismforconsumerstoshiftenvironmentalpollutionassociatedwiththeirconsumptiontoothercountries.ChinahasovertakentheU.S.astheworld'sbiggestCO2emittersince2006.AsChina'ssecondlargesttradepartner,theU.S.hasthebiggesttradedeficitwithChinawhichhasarousedalotofdisputesbetweenthetwoparties.ButsofartheassessmentsofthetradeimbalanceofChina-U.S.havepaidlittleattentiontoenvironmentalimpactsassociatedwiththetradeimbalance.Appliedaninput-outputapproach,thearticleestimatestheamountofCO2embodiedinChina-U.S.tradeduring1997-2007.ItwasfoundthatthroughtradewithChina,theU.S.reduceditsCO2emissionscomparedwithanon-tradescenario.Duetothegreatercarbon-intensityandrelativelylessefficientproductionprocessesofChineseindustry,China-U.S.traderesultedinmoreCO2emissionsinChinaandtheworld.Intheend,thearticlegivessomesuggestions:itisequalandsustainablethattheinternationalaccountingmethodologiesshouldbeimproved,forCO2emissionsresponsibilitymustbedesignedtoaccountforthedynamicnatureofinternationaltrade.
简介:EstablishingpositiveandurgenttargetsforCO2reductionandemissionpeak,andpromotingenergyconservationandenergystructureadjustmentareamongthestrategiestoaddressglobalclimatechangeandCO2emissionsreduction.Theyarealsomeanstobreakthroughtheconstraintsofdomesticresourcesandenvironment,andinternalneeds,toachievesustainabledevelopment.Generallyspeaking,acountry’sCO2emissionpeakappearsafterachievingurbanizationandindustrialization.Bythen,connotativeeconomicgrowthwillappear,GDPwillgrowslowly,energyconsumptionelasticitywilldecrease,andenergyconsumptiongrowthwillslowdown-dependentmainlyonnewandrenewableenergies.Fossilfuelconsumptionwillnotincreasefurther.WhenCO2emissionreachesitspeak,theannualreductionrateofCO2intensityofGDPisgreaterthanGDPannualgrowthrate;andtheannualreductionrateofCO2intensityofenergyuseisgreaterthantheannualgrowthrateofenergyconsumption.Therefore,threeimportantapproachestopromotionofCO2emissionpeakcanbeconcluded:maintainingreasonablecontrolofGDPgrowth,strengtheningenergyconservationtosignificantlyreducetheGDPenergyintensity,andoptimizingtheenergymixtoreducetheCO2intensityofenergyuse.Byaround2030,Chinawillbasicallyhavecompleteditsrapiddevelopmentphaseofindustrializationandurbanization.ConnotativeeconomicgrowthwillappearwiththeaccelerationofindustrialstructureadjustmentThetargetofGDPenergyintensitywillstillbetomaintainanaverageannualreductionof3%orhigher.Theproportionofnon-fossilfuelswillreach20-25%,andtheaimwillbetomaintainanaverageannualgrowthrateof6-8%.Thetotalannualenergydemandgrowthof1.5%willbesatisfiedbythenewlyincreasedsupplyofnon-fossilfuels.TheannualdeclineinCO2intensityofGDPwillreach4.5%orhigher,whichiscompatiblewithanaverageannualGDPgrowth
简介:Inthispaper,weconstructamodelinwhichtheimpactofpollutiononhealthisexertedthroughbothdirectandindirectchannels.Theindirectchanneliscapturedbyaproductionfunc-tioninwhichtheprincipalhealth-improvingfactor,incomegrowth,canberealizedonlyinthecostofpollutionincrease.Thismodelisthentestedbytheaggregatedchroniclediseasedatainover78Chinesecounties.Ourresultsshow,afterattainingthethresholdof8μg/m2,continuousincreaseinindustrialSO2emissiondensitywillleadtheratioofpopulationsufferingchroniclediseases,amongwhichrespiratorydiseasesoccupyasignificantproportion,torise.However,owingtotechnologicalprogressinpollutioncontrolactivities,theneededSO2emissiontoproduceoneunitofGDPdiminisheswithtime.Therefore,thenegativeeffectfrompollutionaugmentationonpublichealthseemstoberecompensedmoreandmorebythepositiveeffectofeconomicgrowth.
简介:ThispaperproposestouseDEAmodelswithundesirableoutputstoconstructtheMalmquistindexthatcanbeusetoinvestigatethedynamicchangesofCO2emissionperformance.Withtheindex,theauthorshavemeasuredtheCO2emissionperformanceof28provincesandautonomousregionsinChinafrom1996to2007;withtheconvergencetheoryandpaneldataregressionmodel,theauthorsanalyzetheregionaldifferencesandtheinfluencingfactors.ItisfoundthattheperformanceofCO2emissionsinChinahasbeencontinuouslyimprovedmainlyduetothetechnologicalprogress,andtheaverageimprovementrateis3.25%,withacumulativeimprovementrateof40.86%.Inaddition,theCO2emissionperformancevariesacrossfourregions.Asawhole,theperformancescoreofeasternChinaisthehighest.ThenortheasternandcentralChinahasrelativelylowerperformancescores,andthewesternChinaisrelativelybackward.Theregionaldifferencesaredecreasing,andtheperformanceofCO2emissionsisconvergent.TheinfluenceofsomefactorsontheperformanceofCO2emissionsissignificant,suchasthelevelofeconomicdevelopment,thelevelofindustrialstructure,energyintensity,andownershipstructure.Theinfluenceofsomefactors,suchasopening-uptotheoutsideworld,ontheperformanceofCO2emissionsisnotsignificant..
简介:WhenaccountingtheCO2emissionsresponsibilityoftheelectricitysectorattheprovinciallevelinChina,itisofgreatsignificancetoconsiderthescopeofbothproducers’andtheconsumers’responsibility,sincethiswillpromotefairnessindefiningemissionresponsibilityandenhancecooperationinemissionreductionamongprovinces.Thispaperproposesanewmethodforcalculatingcarbonemissionsfromthepowersectorattheprovinciallevelbasedonthesharedresponsibilityprincipleandtakingintoaccountinterregionalpowerexchange.Thismethodcannotonlybeusedtoaccounttheemissionresponsibilitysharedbyboththeelectricityproductionsideandtheconsumptionside,butitisalsoapplicableforcalculatingthecorrespondingemissionresponsibilityundertakenbythoseprovinceswithnetelectricityoutflowandinflow.ThismethodhasbeenusedtoaccountforthecarbonemissionsresponsibilitiesofthepowersectorattheprovinciallevelinChinasince2011.Theempiricalresultsindicatethatcomparedwiththeproduction-basedaccountingmethod,thecarbonemissionsofmajorpower-generationprovincesinChinacalculatedbythesharedresponsibilityaccountingmethodarereducedbyatleast10%,butthoseofotherpower-consumptionprovincesareincreasedby20%ormore.Secondly,basedontheprincipleofsharedresponsibilityaccounting,InnerMongoliahasthehighestcarbonemissionsfromthepowersectorwhileHainanhasthelowest.Thirdly,fourprovinces,includingInnerMongolia,Shanxi,HubeiandAnhui,havethehighestcarbonemissionsfromnetelectricityoutflow-14milliontin2011,accountingfor74.42%oftotalcarbonemissionsfromnetelectricityoutflowinChina.Sixprovinces,includingHebei,Beijing,Guangdong,Liaoning,Shandong,andJiangsu,havethehighestcarbonemissionsfromnetelectricityinflow-11milliontin2011,accountingfor71.44%oftotalcarbonemissionsfromnetelectricityinflowinChina.Lastly,thispaperhasestimatedtheemissionfactorsofelectricity
简介:为了探讨纳米与微米尺度SiO2对雄性大鼠的生殖毒性作用,选择不同剂量的纳米SiO2(20~40nm)与微米SiO2(1~10μm)采用气管滴注方式对雄性Wistar大鼠分组染毒.于染毒5周后处死大鼠,检查附睾精子形态,并检测睾丸组织和血清中睾丸功能标志酶活性变化以及性激素含量的变化.结果表明:1)高、低剂量的纳米和微米SiO2染毒均可使大鼠发生程度不同的精子数量减少、精子活动率降低、精子畸形率升高;2)纳米SiO2染毒可使大鼠睾丸组织SDH、LDH和血清中ACP活性显著降低,而微米SiO2染毒对这些指标的影响不显著;3)纳米SiO2和高剂量微米SiO2染毒可使大鼠血清T和睾丸匀浆T浓度显著降低,而对血清LH没有显著影响;4)与微米SiO2相比,纳米SiO2对大鼠生殖功能的损伤有更严重的趋势,但相同剂量下,纳米SiO2和微米SiO2相比,各指标均无显著性差异.以上结果表明,微米和纳米尺度SiO2染毒均可使大鼠生殖功能产生损伤,使部分生殖功能指标发生显著变化;与微米SiO2相比,纳米SiO2对大鼠生殖功能的损伤有更严重的趋势.
简介:Thispaperquantifiesadecompositionanalysisofenergy-relatedCO2emissionsintheindustrialsectorsofShanghaiovertheperiod1994-2007.TheLog-MeanDivisiaIndex(LMDI)methodisappliedtothisstudyintermsofsixfactors:laborforce,labormobility,grosslaborproductivity,energyintensity,fuelmix,andemissioncoefficient.Inaddition,thedecouplingeffectbetweenindustrialeconomicgrowthandCO2emissionsisanalyzedtoevaluateCO2mitigationstrategiesforShanghai.TheresultsshowthatalllaborproductivityhasthelargestpositiveeffectonCO2emissionchangesintheindustrialsectors,whereaslabormobilityandenergyintensityarethemaincomponentsfordecreasingCO2emissions.OtherfactorshavedifferenteffectsonCO2mitigationindifferentsub-periods.AlthougharelativedecouplingofindustrialCO2emissionsfromtheeconomicgrowthinShanghaihasbeenfound,ShanghaishouldkeeppacewiththeindustrialCO2emissionsreductionbyimplementinglow-carbontechnology.Theseresultshaveimportantpolicyimplications:PlanCisthereasonablechoiceforShanghai.
简介:为研究水生生物对水体中重金属和有机磷农药毒性的响应,研究了锯齿新米虾暴露在Cu2+、毒死蜱单一溶液和毒性1:1混合溶液下的响应状况,同时采用相加指数法对混合毒性进行了评价。单一毒性试验结果表明:毒死蜱对锯齿新米虾的毒性显著高于Cu(2+)(p〈0.01);Cu(2+)对锯齿新米虾未觉察反应浓度(NOEC)和最低觉察反应浓度(LOEC)分别为1.78mg·L(-1)、2.40mg·L(-1),24、48、72和96h的LC_(50)分别为6.41、4.75、4.20和3.44mg·L(-1);毒死蜱对锯齿新米虾NOEC和LOEC分别为0.04μg·L(-1)、0.07μg·L(-1),24、48、72和96h的LC50分别为035、0.17、0.11和0.06μg·L(-1);参考鱼类毒性分级标准,Cu(2+)对锯齿新米虾为高毒,而毒死蜱为剧毒。混合毒性试验结果表明:采用Cu(2+)和毒死蜱毒性1:1进行试验时,暴露时间为24、48、72和96h的相加指数(AI)分别为0.02、0.45、1.86和223,即混合毒性为协同作用。通过研究锯齿新米虾对Cu(2+)、毒死蜱单一和联合毒性的响应,可为水环境污染与防治、物种多样性保护提供科学依据。
简介:焦化废水中含有大量毒性物质,具有较强的生物毒性。本文以实验室构建的A2/O焦化废水处理系统为研究对象,考察废水处理过程化学成分和急性毒性的变化。采用紫外扫描和三维荧光光谱分析考察了处理系统各阶段出水的物质组分,并采用固相萃取和超滤膜分离等手段对水样各组分的发光细菌急性毒性进行研究。结果表明,伴随着芳香族物质等毒物的去除,焦化废水的急性生物毒性在该处理系统中被逐步削减,最终出水的毒性当量仅为原水的28%;不同组分的生物毒性测试结果显示,废水水样的强极性和中等极性有机组分贡献了绝大部分的毒性当量,而这些物质主要在缺氧段及好氧段被削减;结合三维荧光光谱的分析结果,可推断焦化废水中一类很难在A2/O处理系统中被完全去除的芳香族蛋白质类似物(Ⅱ区)很可能具有较强的生物毒性,是构成出水毒性的主要物质。
简介:随着环境重金属污染的加剧和营养学的发展,人们越来越重视对重金属元素及营养金属元素肠道吸收过程的探讨及其生物有效性影响因素的研究.Caco-2细胞模型能有效的模拟人体小肠上皮细胞的转运与吸收过程,可结合基因技术、分子技术等手段用于研究人体肠道吸收物质的机制和影响因素.首先,总结了近年来利用Caco-2模型对镉、铬、铅、砷等多种重金属及铜、铁、锌、钙等多种营养金属在小肠内的吸收、转运方式、代谢机制及影响吸收、转运过程的各类条件等的研究工作,然后对Caco-2细胞模型研究方法及其在未来评估金属人体生物有效性的应用进行了展望.
简介:为探明妊娠早期胚胎的丢失是否与卵巢、输卵管、子宫组织受到2,3,7,8-四氯苯并二噁英(TCDD)直接毒害有关,检测了NIH小鼠胚胎着床前期和后期TCDD暴露对胚胎毒性影响的敏感性,并利用免疫组化方法分析了模型动物肝脏、子宫、输卵管和卵巢组织中TCDD所引起的AhR、ARNT以及Cyp1a2分子标记物的变化.检测发现:妊娠第9d,100ng·kg-1·d-1剂量TCDD经口染毒,造成胚胎着床数量减少,且着床前期暴露的影响大于着床后期;子宫蜕膜反应受到明显抑制;胚胎迁移率没有明显变化,但胚胎数量减少.免疫组织化学分析发现正常组小鼠的肝脏、子宫、输卵管和卵巢组织中有AhR和Cyp1a2弱阳性信号表达,ARNT有细胞核的强阳性信号表达;妊娠第1~8d、第1~3d和第4~8d处理组小鼠肝脏、子宫、输卵管和卵巢组织中的AhR、Cyp1a2的阳性面积和光密度值均高于正常组;随处理时间和组织蓄积量的增加,ARNT在组织中的变化由胞核(妊娠第1~3d组)表达到胞浆(妊娠第4~8d组)表达,然后完全无表达(妊娠第1~8d组).以上研究结果表明:TCDD对早期妊娠小鼠子宫、输卵管和卵巢组织中的AhR、ARNT和Cyp1a2的激活和代谢方式与肝脏相同,说明雌性生殖系统中的组织有TCDD蓄积和代谢活性,这可能是导致早期胚胎迁移、着床等过程改变,造成胚胎丢失的重要原因.