简介:CarboncycleisconnectedwiththemostimportantenvironmentalissueofGlobalChange.Asoneofthemajorcarbonreservoirs,oceansplayanimportantpartinthecarboncycle.Inrecentyears,ironseemstogiveusagoodnewsthatoceanicironfertilizationcouldstimulatebiologicalproduc-tivityasCO2sinkofhuman-producedCO2.Oceanicironfertilizationexperimentshaveverifiedthataddingironintohighnutrientlowchlorophyll(HNLC)seawaterscanincreasephytoplanktonproductionandexportorganiccarbon,andhenceincreasecarbonsinkofanthropogenicCO2,toreduceglobalwarming.Insixtydays,theexportorganiccarboncouldreach10000timesforaddingironbymodelpredictionandinsituexperiment,I.e.TheatmosphericCO2uptakeandinorganiccarbondrawdowninupperseawatersalsohavethesamemagnitude.Therefore,oceanicironfertilizationisoneofthestrate-giesforincreasingcarbonsinkofanthropogenicCO2.Thepaperisfocusedontheironfertilization,es-peciallyinsituoceanironexperimentsinorderthatthefutureresearchismoreefficient.
简介:OnthebasisofdatacollectedintheJiaozhouBayinJuneandJuly2003,theDICdistributioninseawaterisstudied,andanaverageair-seafluxofCO2isestimated.TheresultsshowthatthecontentofDICinsidethebayismarkedlyhigherthanoutsidethebayinJune,butthecontentofDICoutsidethebayismarkedlyhigherthaninsidethebayinJuly.ThetrendofDICdistributioninsidethebayissimilar,viz.thecontentisthemaximuminthenortheast,thendecreasesgraduallytowardthewest,andthecontentistheminimuminthewest.Thetotaltrendofverticaldistributionistoincreasegraduallyfromsurfacetobottom.ThischaracteristicofDICdistributionisdeterminedbyJiaozhouBayhydrologyandthereisacloserelationbetweenDICandparticulateN,P.AverageCO2fluxacrossthesourceforatmosphericCO2inJuneandJuly,andthetotalCO2fluxfromseawaterintoatmosphereisabout740tinJuneand969tinJuly.
简介:Althoughtheannualglobalsea-airCO2fluxhasbeenestimatedextensivelywithvariouswind-dependent-kparameterizations,uncertaintystillexistsintheestimates.Thesea-state-dependent-kparameterizationisexpectedtoimprovetheuncertaintyexistingintheseestimates.Inthepresentstudy,theannualglobalsea-airCO2fluxisestimatedwiththesea-state-dependent-kparameterizationproposedbyWoolf(2005),usingNOAA/NCEPreanalysiswindspeedandhindcastwavedatafrom1998to2006,andanewestimate,-2.18GtCyear-1,isobtained,whichiscomparablewithpreviousestimateswithbiochemicalmethods.Itisinterestingtonotethattheaveragedvalueofpreviousestimateswithvariouswind-dependent-kparameterizationsisalmostidenticaltothatofpreviousestimateswithbiochemicalmethodsbyvariousauthors,andthatthenewestimateisquiteconsistentwiththeseaveragedestimates.
简介:Intertidalmarinemacroalgaeexperienceperiodicalexposuresduringlowtideduetotheirzonationaldistribution.ThedurationofsuchemersionleadstodifferentexposuresoftheplantstolightandaerialCO2,whichthenaffectthephysiologyofthemtodifferentextents.TheecophysiologicalresponsestolightandCO2wereinvestigatedduringemersionintworedalgaeGloiopeltisfurcataandGigartinaintermedia,andtwobrownalgaePetaloniafasciaandSargassumhemiphyllum,growingalongtheShantoucoastofChina.Thelight-saturatednetphotosynthesisinG.furcataandP.fasciashowedanincreasefollowedbyslightlydesiccation,whereasthatinG.intermediaandS.hemiphyllumexhibitedacontinuousdecreasewithwaterloss.Inaddition,theupper-zonatedG.furcataandP.fascia,exhibitedhigherphotosynthetictolerancetodesiccationandrequiredhigherlightleveltosaturatetheirphotosynthesisthanthelower-zonatedG.intermediaandS.hemiphyllum.Desiccationhadlesseffectondarkrespirationinthesefouralgaecomparedwithphotosynthesis.Thelight-saturatednetphotosynthesisincreasedwithincreasedCO2concentrations,beingsaturatedatCO2concentrationshigherthanthepresentatmosphericlevelinG.furcata,G.intermediaandS.hemiphyllumduringemersion.ItwasevidentthattherelativeenhancementofphotosynthesisbyelevatedCO2inthosethreealgaeincreased,thoughtheabsolutevaluesofphotosyntheticenhancementowingtoCO2increasewerereducedwhenthedesiccationstatusesbecamemoresevere.However,inthecaseofdesiccatedP.fascia(waterlossbeinggreaterthan20%),lightsaturatednetphotosynthesiswassaturatedwithcurrentambientatmosphericCO2level.ItisproposedthatincreasingatmosphericCO2willenhancethedailyphotosyntheticproductioninintertidalmacroalgaebyvariedextentsthatwererelatedtothespeciesandzonation.
简介:一个全球海洋碳周期模型基于海洋将军发行量模型流行音乐和改进biogeochemical模型,OCMIP-2被采用在历史上观察的大气的CO2集中和不同未来情形(叫的代表性的集中小径,或RCP)下面模仿碳周期过程。在这份报纸的RCP为第五份评价报告(AR5)在气候变化(IPCC)上跟随Intergovernmental面板的设计。模型结果证明海洋从空气吸收CO2,被吸收将在四RCP下面在第21世纪继续。由空至海的CO2流动在历史的时间期间增加了并且到达的网1.87Pg/a(由碳计算了)在2005;然而,它将在第21世纪到达山峰然后减少。海洋主要专心于CO2中间的纬度,并且在赤道区域释放CO2。然而,在南极围绕天极的水流(ACC)区域,海洋将在升起的CO2集中下面从来源改变到水池,包括RCP4.5,RCP6.0,和RCP8.5。在2100,人为的碳将被搬运到40摥漠敶?桴?湥楴敲礠慥?獩爠畯桧祬?呼??湡?桴?潲敬漠???獩琠敨猠慭汬獥t
简介:通过实地考察和资料分析,海南岛南部全新世以来以沉降活动为主要特征,鹿回头珊瑚礁能够反映全新世以来的海平面变化,鹿回头岸礁礁坪面上的原生珊瑚礁是全新世高海平面时期的产物。全新世以来南海北部至少存在过4期相对高海平面阶段:7300-6000、4800-4700、4300-4200和3100-2900cal.aBP。其中7300-6000aBP是整个全新世最高海平面时期,也是鹿回头珊瑚礁发育的繁盛期,基本形成了现代珊瑚礁的地貌格局,后来不同时期发育的珊瑚礁是在此时期形成的礁塘或礁坑等低洼地中形成,并在鹿回头半岛两侧向外发展,现代珊瑚礁则发育于全新世珊瑚礁的外礁坪和礁前斜坡带。另外,鹿回头珊瑚礁反映的南海北部全新世高海平面时间与南海其他地区高海平面时间可以衔接或对应,说明南海地区全新世高海平面具有全球背景,至少在南海是一致的,且与气候变暖紧密相联。
简介:提出了一种基于多分辨率小波高频特征系数的高光谱遥感影像亚像素目标识别方法.首先利用多尺度小波变换将光谱信号分解为不同尺度的高频特征信号,然后借助接收操作特性曲线(ROC)和马氏距离投影寻踪求取一维最佳识别特征,最后通过高斯最大似然决策函数求解亚像素目标的存在概率.通过38种小波函数的高光谱数据实验证明,该方法对亚像素目标的识别效果较好.
简介:Multi-beamSonarandSide-scanSonarcompensateeachother.Inordertofullyutilizeallinformation,itisnecessarytofusetwokindsofimageanddata.Andtheimageco-registrationisanimportantandcomplicatedjobbeforefusion.Thispapersuggestscombiningbathymetricdatawithintensityimage,obtainingthecharacteristicpointsthroughtheminimalanglesoflines,andthendecidingthecorrespondingimagepointsbythemaximalcorrelatecoefficientinsearchingspace.Finally,thesecondorderpolynomialisappliedtothedeformationmodel.Aftertheimageshavebeenco-registered,Waveletisusedtofusetheimages.Itisshownthatthisalgorithmcanbeusedintheflatseafloorortheisotropicseabed.Verificationismadeinthepaperwiththeobserveddata.
简介:Thecurrentadvancesinthestudyofgeochemistryandpaleo-oceanographyoftheCo-richcrustarereviewedinthispaper.WesummarizethestudyofgeochemistryoftheCo-richcrust,discussthediffusionofelementsintheCo-richcrustandtheexchangewithambientseawater.Besides,wediscusstheeffectofphosphatizationandsubstraterocksonthecompositionoftheCo-richcrust.Wealsointroducetheapplicationofstableisotopes(includingthestableisotopesofPb,Nd,andHf),radioactiveisotopes(includingtheradioactiveisotopesofBe,UandTh),andelements(includingthemajorelements,minorelementsandrareearthelements)tothestudyofpaleo-oceanographyoftheCo-richcrust.
简介:完全的mitochondrial细胞色素氧化酶子单元II(COII)基因ofPenaeinae虾Fenneropenaeuschinensis被克隆并且定序。基因为229氨酸是在长度和代码的688bp。它显示出83.2%,87.0%和83.8%顺序类似到Marsupenaeusjaponicus,Penaeus单音穿上并且Farfantepenaeusnotialis分别地。在鳕鱼ons的第三个位置的整个基因和那的A+T内容分别地是64.7%和78.2%。在F之间的种系发生的关系。chinensis和代表类Farfanatepenaeus,Marsupenaeus和Penaeus的三另外的种被分析。结果证明在四taxaranged从之中的基因距离0.1440~0.2005,超过与COI和部分16SrRNA基因估计的那些在Marsupenaeus,Litopenaeus和Melicertus之中定序,并且因此比在潜水艇类之中的价值大。COII基因比COI基因和部分16SrRNA基因的有更快的进化的率,这被建议了并且能在类或种水平被用于种系发生的分析。现在的学习的结果显示Farfantepenaeus,Fenneropenaeus,Marsupenaeus和Penaeus比亚属在更高种系发生的水平,它支持四个潜水艇类的种系发生的地位的举起的意见到类水平。
简介:Thegrowth,biochemicalcontentandbioaccumulationquantityof2,2’,4,4’-tetrabromodiphenylether(BDE-47)inSkeletonemacostatumwerestudiedunderdifferentN:Pratios(1,4,16,64and128).AllcellularbiochemicalcontentsofS.costatumpresenteddecreasingtrendovercultivationtime.Atearlystageofcultivation,thecellularprotein,carbohydrateandlipidinS.costatumpresentedhighervaluesintreatmentsofN:P=4and16.However,theywerelowerinthesetreatmentsatthelatestage,buthigherintreatmentsN:P=1and128.Similarly,BDE-47levelspercellofS.costatumwerehigherintreatmentsofN:P=4and16atearlystageofcultivation,whichwere3.8and3.7ng(106cells)-1,respectively.Atthemiddlestageofcultivation,theBDE-47levelperS.costatumcelllowered;anditfurtherreducedinthetreatmentsofN:P=4and16atthelatestagewiththevalues0.6and0.5ng(106cells)-1,respectively.However,itroseinN:P=128,reachingupto2.3ng(106cells)-1.ComparedwithBDE-47percell,BDE-47peralgalvolumeunderdifferentN:Pratiosdidnotpresentobviousdifference.ThequantityBDE-47accumulatedpercellofS.costatumwaspositivelycorrelatedwithprotein,carbohydrateandlipidpercell;meanwhile,theBDE-47pervolumehadapositivecorrelationwithbiochemicalcontentpervolume.ThevariationofbioaccumulationabilityofBDE-47inS.costatumcanbeexplainedbybiochemicalchangesduetoN:Pratios.
简介:TiO2filmswereformedonmetallictitaniumsubstratesbytheanodicoxidationmethodinH2SO4solutionunderthe80VD.C..PhasecomponentandmicrostructurewerecharacterizedbyX-raydiffraction(XRD)andscanningelectronmicroscopy(SEM).Watercontactanglesontitaniumoxidefilmsurfaceweremeasuredunderbothdarkandsunlightilluminationconditions.Corrosiontestswerecarriedoutinseawaterunderdifferentilluminationconditionsbyelectrochemistryimpedancespectrum(EIS)andpolarizationcurves.TheresultshowedthattheTiO2filmpreparedbytheanodicoxidationmethodwasanatasewithauniformstructureandwithoutobviousporesorcracksonitssurface.Theaveragewatercontactangleofthefilmwas116.4?indark,incontrasttoanangleof42.7?undertheUVilluminationfor2hours,whichdemonstratesgoodhydrophobicproperty.Theanti-corrosionbehavioroftheTiO2filmwasdecliningwiththeextendedimmersiontime.Underdarkconditions,however,thehydrophobicTiO2filmretardedthewaterinfiltratingintothesubstrate.Theimpedancechangedslowlyandthecorrosioncurrentdensitywas2ordersofmagnitudelowerthanthatwiththefilmilluminatedbysunlight.AllofthosementionedaboveindicatethattheTiO2filmpossessesmuchbetterperformanceunderdarkcondition,anditcanbeappliedasanengineeringmaterialunderdarkseawaterenvironment.
简介:Astochastictwo-dimensionalFornasini-Marchesini'sModelⅡ(2-DFMMⅡ)withmultiplicativenoiseisgiven,andafilteringalgorithmforthismodel,whichisoptimalinthesenseoflinearminimum-variance,isdeveloped.Thestochastic2-DFMMⅡwithmultiplicativenoisecanbereducedtoa1-Dmodel,andtheproposedoptimalfilteringalgorithmforthestochastic2-DFMMⅡwithmultiplicativenoiseisobtainedbyusingthestateestimationtheoryof1-Dsystems.Anexampleisgiventoillustratethevalidityofthisalgorithm.
简介:Thispaperpresentsthedetaildesignconditions,designcriteriaandmethodsaswellasdesignconclusionsoftheprocess,structureandcorrosionoftheproductionflowlinesandhighpressurewaterinjectionlinesinBZ34-2/4oilfieldinBohaiBay.AtpresentthisdesignrepresentsthedesigncapabilityandlevelinthefieldofthesubmarinepipelineengineeringofChina.
简介:Inthisstudy,thecombinedactionsofwavesandtidalcurrentsinestuarineandcoastalareasareconsideredanda2Dmathematicalmodelforsedimenttransportbywavesandtidalcurrentshasbeenestablishedinorthogonalcurvilinearcoordinates.Non-equilibriumtransportequationsofsuspendedloadandbedloadareusedinthemodel.Theconceptofbackgroundconcentrationisintroduced,andtheformulaofsedimenttransportcapacityoftidalcurrentsfortheOujiangRiverestuaryisobtained.TheDouGuorenformulaisemployedforthesedimenttransportcapacityofwaves.SedimenttransportcapacityintheformofmudandtheintensityofbacksiltingarecalculatedbyuseofLuoZaosen'sformula.Thecalculatedtidalstagesareingoodagreementwiththefielddata,andthecalculatedvelocitiesandflowdirectionsof46verticallinesfor8crosssectionsarealsoingoodagreementwiththemeasureddata.Onsuchabasis,simulationsofbacksiltingafterexcavationofthewaterwaywithasandbarundercomplicatedboundaryconditionsinthenavigationchannelinducedbysuspendedload,bedloadandmudbywavesandtidalcurrentsarediscussed.