简介：TheimpactofpHchangesonmicrobialbiomasscarbon(Cmic)andmicrobialbiomassphosphorus(Pmic)wereexaminedfor3redsoilsundercitrusproductionwithdifferentlengthsofcultivation.SoilpHsignificantlyaffectedCmicandPmic.TheCmicandPmicchanges,asafunctionofsoilpH,appearedtofollowanormaldistributionwiththeoriginalsoilpHvalueattheapexandaspHincreasedordecreasedcomparedtotheoriginalsoilpH,CmicandPmicdeclined.Moreover,therewerecriticalpHvaluesatbothextremes(3.0ontheacidicsideand8.0to8.5onthealkalineside),beyondwhichmostofmicroorganismscouldneversurvive.TheeffectofpHonCmicandPmicwasalsorelatedtotheoriginalsoilpH.ThehighertheoriginalsoilpHwas,thelessCmicorPmicwereaffectedbypHchange.ItissuggestedthatsoilmicroorganismsthatgrowinasoilenvironmentwithamoreneutralsoilpHrange(I.e.pH5.5-7.5)mayhaveagreatertolerancetopHchangesthanthosegrowinginmoreacidicormorealkalinesoilpHconditions.

简介：Background:Dependingontreeandsitecharacteristicscrownbiomassaccountsforasignificantportionofthetotalabovegroundbiomassinthetree.Crownbiomassestimationisusefulfordifferentpurposesincludingevaluatingtheeconomicfeasibilityofcrownutilizationforenergyproductionorforestproducts,fuelloadassessmentsandfiremanagementstrategies,andwildfiremodeling.However,crownbiomassisdifficulttopredictbecauseofthevariabilitywithinandamongspeciesandsites.Thustheallometricequationsusedforpredictingcrownbiomassshouldbebasedondatacollectedwithpreciseandunbiasedsamplingstrategies.Inthisstudy,weevaluatetheperformancedifferentsamplingstrategiestoestimatecrownbiomassandtoevaluatetheeffectofsamplesizeinestimatingcrownbiomass.Methods:Usingdatacollectedfrom20destructivelysampledtrees,weevaluated11differentsamplingstrategiesusingsixevaluationstatistics:bias,relativebias,rootmeansquareerror(RMSE),relativeRMSE,amountofbiomasssampled,andrelativebiomasssampled.Wealsoevaluatedtheperformanceoftheselectedsamplingstrategieswhendifferentnumbersofbranches(3,6,9,and12)areselectedfromeachtree.Treespecificloglinearmodelwithbranchdiameterandbranchlengthascovariateswasusedtoobtainindividualbranchbiomass.Results:Comparedtoallothermethodsstratifiedsamplingwithprobabilityproportionaltosizeestimationtechniqueproducedbetterresultswhenthreeorsixbranchespertreeweresampled.However,thesystematicsamplingwithratioestimationtechniquewasthebestwhenatleastninebranchespertreeweresampled.Underthestratifiedsamplingstrategy,selectingunequalnumberofbranchesperstratumproducedapproximatelysimilarresultstosimplerandomsampling,butitfurtherdecreasedRMSEwheninformationonbranchdiameterisusedinthedesignandestimationphases.Conclusions:UseofauxiliaryinformationindesignorestimationphasereducestheRMSEproducedbyasamplingstrategy.Howe

简介：AbundanceandbiomassofheterotrophicmicrobeswereinvestigatedusingepifluorescensemicroscopyinAugust2004alongatransectintheKongsfjorden,aglacialfjordinthehigharctic,locatedinthenorth-westernpartofSvalbard.Abacterialabundancewaslowatouterfjordstations(onaverage2.29×108ind./dm3)andwashigheratinnerfjordstations(onaverage3.52×108ind./dm3).Thebiomassofbacteriarangedfrom3.69to8.01mg/m3.Theabundanceofbacteriawaslowatthesurfaceofwater(0m),whereasthehigherabundancesoftenoccurredatdepthsof30～50m.Theabundanceofheterotrophicflagellatesvariedfrom2.785to8.891×104ind./dm3.Theassemblagewasnumericallydominatedbylessthan5μmheterotrophicflagellates(78.67%～94.80%).Thebiomassofheterotrophicflagellatesvariedfrom0.37to2.30mg/m3.Themeanbiomassdistributionforallstationswas4.91%forlessthan5μmheterotrophicflagellates,86.74%for6～20μmflagellatesand8.35%forgreaterthan20μmsizedflagellates.Thelowbiomassofheterotrophicflagellatesoftenoccurredatthesurfaceofwater(0m),whilethemaximumvalueofbiomassoccurredatdifferentdepths.Thebiomassoftotalheterotrophicmicrobialcommunityrangedfrom4.20to10.03mg/m3.Themeanbiomassdistributionforallstationswas82.58%forbacteria,15.77%forflagellatesand1.66%forciliates.

简介：Inthelastdecadestheinterestinthebiomassgasificationprocesshasincreasedduetothegrowingattentiontotheuseofsustainableenergy.Biomassisarenewableenergysourceandrepresentsavalidalternativetofossilfuels.Gasificationisthethermochemicalconversionofanorganicmaterialintoavaluablegaseousproduct,calledsyngas,andasolidproduct,calledchar.Thebiomassgasificationrepresentsanefficientprocessfortheproductionofpowerandheatandtheproductionofhydrogenandsecond-generationbiofuels.Thispaperdealswiththestateoftheartbiomassgasificationtechnologies,evaluatingadvantagesanddisadvantages,thepotentialuseofthesyngasandtheapplicationofthebiomassgasification.Syngascleaningthoughfundamentaltoevaluateanygasificationtechnologyisnotincludedinthispapersince;intheauthors'opinion,adedicatedreviewisnecessary.

简介：Background:Biomassregressionequationsareclaimedtoyieldthemostaccuratebiomassestimatesthanbiomassexpansionfactors(BEFs).Yet,nationalandregionalbiomassestimatesaregenerallycalculatedbasedonBEFs,especiallywhenusingnationalforestinventorydata.ComparisonofregressionequationsbasedandBEF-basedbiomassestimatesarescarce.Thus,thisstudywasintendedtocomparethesetwocommonlyusedmethodsforestimatingtreeandforestbiomasswithregardtoerrorsandbiases.Methods:Thedatawerecollectedin2012and2014.In2012,atwo-phasesamplingdesignwasusedtofittreecomponentbiomassregressionmodelsanddeterminetreeBEFs.In2014,additionaltreeswerefelledoutsidesamplingplotstoestimatethebiasesassociatedwithregressionequationbasedandBEF-basedbiomassestimates;thoseestimateswerethencomparedintermsofthefollowingsourcesoferror:plotselectionandvariability,biomassmodel,modelparameterestimates,andresidualvariabilityaroundmodelprediaion.Results:Theregressionequationbasedbelow-,abovegroundandwholetreebiomassstockswere,approximately,7.7,8.5and8.3%largerthantheBEF-basedones.Forthewholetreebiomassstock,thepercentageofthetotalerrorattributedtofirstphase(randomplotselectionandvariability)was90and88%forregression-andBEF-basedestimates,respeaively,beingtheremainingattributedtobiomassmodels(regressionandBEFmodels,respeaively).ThepercentbiasofregressionequationbasedandBEF-basedbiomassestimatesforthewholetreebiomassstockwere-2.7and5.4%,respeaively.Theerrorsduetomodelparameterestimates,thoseduetoresidualvariabilityaroundmodelprediaion,andthepercentageofthetotalerrorattributedtobiomassmodelwerelargerforBEFmodels(thanforregressionmodels),exceptforstemandstemwoodcomponents.Conclusions:Theregressionequationbasedbiomassstockswerefoundtobeslightlylarger,associatedwithrelativelysmallererrorsandleastbiasedthantheBEF-basedones.Forstemandst

简介：Background:Europeanforestsareconsideredacrucialresourceforsupplyingbiomasstoagrowingbio-economyinEurope.ThisstudyaimedtoassessthepotentialavailabilityofforestbiomassfromEuropeanforestsanditsspatialdistribution.Wetriedtoanswerthequestions(i)howisthepotentialforestbiomassavailabilityspatiallydistributedacrossEuropeand(ii)wherearehotspotsofpotentialforestbiomassavailabilitylocated?Methods:Thespatialdistributionofwoodybiomasspotentialswasassessedfor2020forstemwood,residues(branchesandharvestlosses)andstumpsfor39Europeancountries.UsingtheEuropeanForestInformationSCENario(EFISCEN)modelandinternationalforeststatistics,weestimatedthetheoreticalamountofbiomassthatcouldbeavailablebasedonthecurrentandfuturedevelopmentoftheforestage-structure,growingstockandincrementandforestmanagementregimes.Wecombinedtheseestimateswithasetofenvironmental(siteproductivity,soilandwaterprotectionandbiodiversityprotection)andtechnical(recoveryrate,soilbearingcapacity)constraints,whichreducedtheamountofwoodybiomassthatcouldpotentiallybeavailable.Wemappedthepotentialbiomassavailabilityatthelevelofadministrativeunitsandatthe10km×10kmgridleveltogaininsightintothespatialdistributionofthewoodybiomasspotentials.Results:Accordingtoourresults,thetotalavailabilityofforestbiomassrangesbetween357and551Tgdrymatterperyear.ThelargestpotentialsupplyofwoodybiomassperunitoflandcanbefoundinnorthernEurope(southernFinlandandSweden,EstoniaandLatvia),centralEurope(Austria,CzechRepublic,andsouthernGermany),Slovenia,southwestFranceandPortugal.However,largepartsofthesepotentialsarealreadyusedtoproducematerialsandenergy.Thedistributionofbiomasspotentialsthatarecurrentlyunusedonlypartiallycoincideswithregionsthatcurrentlyhavehighlevelsofwoodproduction.Conclusions:Ourstudyshowshowthefo

简介：ThebiomassesoffishesatthebottomlayeroftheBohaiSeaareextimatedbyanalysingthedataonsamples(447hauls,morethan0.2millioninnumberor20tinweightoffishes)collectedmonthlybyourinstitutefromApril,1982toMay,1983byapairofbottomtrawlsthroughtheBohaiSea.Theexploitationproblemsarealsodiscussedinthispaper.

简介：OnthebasisofthedataofoceanographicsurveyintheEastChinaSeainfourseasonsduring1997～2000(23°30′～33°00′N,118°30′～128°E),thevariationoftotalbiomassanddietbiomassofzooplanktonandtheirspatial-temporaldistributionandrelationshipwiththefishinggroundofEngraulisjaponicusareapproachedandanalyzed.Theresultsshowthattheaveragebiomassis65.32mg/m3infourseasons,autumn(86.18mg/m3)beinggreaterthansummer(69.18mg/m3)greaterthanspring(55.67mg/m3)greaterthanwinter(50.33mg/m3).Theaveragevalueofdietzooplanktonbiomassis40.9mg/m3.Thetrendsofhorizontaldistributionbothinthetotalbiomassandthedietbiomassofzooplanktonaresimilar.Thehighbiomassregion(250～500mg/m3)isverylimited,onlyaccountingfor1%oftheinvestigationarea.SeasonalvariationofthebiomassisveryremarkableinthewestandnorthpartsofEastChinaSeacoastalwaters(29°30′N,125°E).Thehorizontaldistributionofdietzooplanktondependsontheabundancedistributionofcrustacean.ThedistributionofdietzooplanktonisrelatedtothefishinggroundofEngraulisjaponicusandthehigh-densityareaofyoungfishandlarval.Inspring,thecentralfishinggroundofEngraulisjaponicus(＞100kg/h)andthehigh-densityareaofyoungfishandlarval(＞100individualspernet)arelocatedatthesameplaceofhigh-density(100～250mg/m3)areaofdietzooplanktoninthemiddle-southernpartofEastChinaSeaortheedgeofitswaters.

简介：AtpresentbiomassenergyindustryisinitsinfancyinChinaandithasabrightfuture.Biomassenergyproductionusedgrainasrawmaterialshasenteredindustrializationphase.Somekeytechnologiesofbiomassenergyindustryarecomingtomature.Chinahasissuedrelevantindustrialstandardslawsandregulations,andhasprovidedsupportinfinance,loan,tax,etc.ButChina'sbiomassenergyindustryisfacedwithmanyproblemswhichneedtobesolved.Forexample,takinggrainasrawmaterialsisunsustain...

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简介：Basedonsixthandseventhnationalforestryinventorydataofthesixprovinces,includingGuangdong,Jiangxi,Guizhou,Shaanxi,JilinandBeijing,thethreemethods(IPCC,continuousfunctionforbiomassexpansionfactorandweightedbiomassregressionmodel)wereselectedtoestimatewoodbiomassinthispaper.Theestimationofthethreemethodswerecomparedandanalyzedfromcalculatingprocess,methodcharacters,repeatabilityandverifiabilitytostabilityofgrowthrateofbiomassbetweentwoperiods.TheresultsshowedthetotalbiomassestimatedbyIPCCmethodwithvariableBEF2waslarge,thetotalbiomassestimatedbyIPCCmethodwithconstantBEF2wassmallandthetotalbiomassesestimatedbycontinuousfunctionforbiomassexpansionfactorandweightedbiomassregressionmodelweremiddle.Thebiomassexpansionfactorderivedfromweightedregressionmodelwasmoststableinthedifferentprovinces.Basedontheseventhnationalforestryinventorydata,thebiomassexpansionfactorsofvariouskindsoftreespeciesderivedfromIPCCandtheweightedregressionmodelweremorestablethanthebiomassexpansionfactorsderivedfromcontinuousfunctionmethod.Thegrowthrateofbiomassbetweentwoperiodswasthesameregularpatternasthebiomassexpansionfactors.

简介：Thisstudywasdesignedtounderstandtheimpactofmethylbromide(MB)(CH3Br)anditsalternativesonbothfree-livingandroot-knotnematodesinthesoil.Arandomizedcompleteblockexperimentwithsixtreatmentsand4replicates(eachreplicateinaseparategreenhouse)wasestablishedinQingzhou,ShandongProvince,China.InadditiontoMBanduntreatedcontrol(CK)treatmentstherewerefouralternativesoilfumigationpracticesincludingMB+virtuallyimpermeablefilms(VIF),metamsodium(MS),MS+VIFandsoilsolarizationcombinedwithselectedbiologicalcontrolagents(SS+BCA).Twotomato(LycopersicumesculentumMill.)cultivars,cv.Maofen-802fromtheXianInstituteofVegetableScience,China,andcv.AF179BrillantefromtheIsraeliHazeraQualitySeeds,wereselectedastestcrops.TheresultsindicatedthatRhabditidaewasthemostdominantpopulationwithpercentageabundanceashighas85%ofthetotalnumberofidentifiedfree-livingnematodes,followedbythatofCephalobidae.Methylbromideanditsalternativesexceptforthenon-chemicalSS+BCAtreatmentcontrolledthetargetpest,root-knotnematodes.Also,theimpactofthethreechemicalalternativesonfree-livingnematodenumberandfunctionalgroupabundancewassimilartotheimpactassociatedwithatypicalmethylbromideapplication.Chemicalfumigationpractices,especiallythatwithMB,significantlyreducedthenumberofnematodesinthesoilandsimultaneouslysignificantlyreducedthenumberofnematodegeneratherebyreducingnematodediversity.Allthefoursoilchemicalfumigationactivitiesdecreasedsoilmicrobialbiomassandhadanobviousinitialimpactonmicroorganismbiomass.Furthermore,bothplant-parasiticandfungivorenematodeswerepositivelycorrelatedwithsoilmicrobialbiomass.

简介：ThebiomassandenergyproductionofCasuarinaequisetifoliaplantationsaged14werestudiedinHuianCounty,FujianProvince,SoutheastofChina.Thestandingcropbiomasswas152.60t/ha,inwhichthebiomassofbolewas67.02t/ha,accountingfor43.94%ofthetotal,whilethatofrootwas36.83t/haand24.14%,respectively.Netprimaryproductivitywas10.17t/(ha.a).Therangeofgrosscaloricofcomponentswas19.29～20.23kJ/g,withtheaverage19.70kJ/g.Thestandingcropenergywas2987×10^6kJ/ha.Netenergyproductionwas196.8×10^6kJ/ha,whilesolarenergyconversionefficiencywas0.90%.

简介：Addressingclimatechangehasbecomeacommonissuearoundtheworldinthe21stcenturyandequallyanimportantmissioninChineseforestry.UnderstandingthedevelopmentofmonitoringandassessmentofforestbiomassandcarbonstorageinChinaisimportantforpromotingtheevaluationofforestcarbonsequestrationcapacityofChina.Theauthorconductsasystematicanalysisofdomesticpublicationsaddressing'monitoringandassessmentofforestbiomassandcarbonstorage'inordertounderstandthedevelopmenttrends,describesthebriefhistorythroughthreestages,andgivesthesituationofnewdevelopment.Towardstheendofthe20thcentury,alargenumberofpapersonbiomassandproductivityofthemajorforesttypesinChinahadbeenpublished,coveringtheexplorationandeffortsofmorethan20years,whileinvestigationsintoassessmentofforestcarbonstoragehadbarelybegun.Basedonthedataofthe7thand8thNationalForestInventories,forestbiomassandcarbonstorageoftheentirecountrywereassessedusingindividualtreebiomassmodelsandcarbonconversionfactorsofmajortreespecies,bothpreviouslypublishedandnewlydeveloped.Accompanyingtheimplementationofthe8thNationalForestInventory,aprogramofindividualtreebiomassmodelingformajortreespeciesinChinawascarriedoutsimultaneously.Bymeansofthematicresearchonclassificationofmodelingpopulations,aswellasproceduresforcollectingsamplesandmethodologyforbiomassmodeling,twotechnicalregulationsonsamplecollectionandmodelconstructionwerepublishedasministerialstandardsforapplication.Requestsforapprovalofindividualtreebiomassmodelsandcarbonaccountingparametersofmajortreespecieshavebeenissuedforapprovalasministerialstandards.Withtheimprovementofbiomassmodelsandcarbonaccountingparameters,thematicassessmentofforestbiomassandcarbonstoragewillbegraduallychangedintoageneralmonitoringofforestbiomassandcarbonstorage,inordertorealizetheirdynamicmoni

简介：China'sforestscover208.3millionhaandspanawiderangeofclimatesandalargevarietyofforesttypes,includingtropical,temperate,andborealforests.However,thevariationpatternsoffineroot(\2mmindiameter)biomass,production,andturnoverfromthesouthtothenorthareunclear.Thisstudysummarizesfinerootbiomass(FRB),production(FRP)andturnoverrate(FRT)inChina'sforestsasreportedby140casestudiespublishedfrom1983to2014.TheresultsshowedthatthemeanvaluesofFRB,FRPandFRTinChina'sforestswere278gm-2,366gm-2a-1,and1.19a-1,respectively.Comparedwithotherstudiesattheregionalorglobalscales,FRBinChina'sforestswaslower,FRPwassimilartoestimatesattheglobalscale,butFRTwasmuchhigher.FRB,FRP,andFRTinChina'sforestsincreasedwithincreasingmeanannualprecipitation(MAP),indicatingthatfinerootvariableswerelikelyrelatedtoMAP,ratherthanmeanannualtemperatureorlatitude.Thisispossiblyduetothesmallvariationintemperaturebutgreatervariationinprecipitationduringthegrowingseason.ThesefindingssuggestthatspatiotemporalvariationinprecipitationhasamoreprofoundimpactonfinerootdynamicsinChina'sforests,andthiswillimpactcarbonandnutrientcyclesdrivenbyrootturnoverinthefuture.

简介：Alaboratoryincubationexperimentwasconductedtostudytheinfluenceofcadmium(Cd),lead(Pb)andzinc(Zn)onthesizeofthemicrobialbiomassinredsoil.Allthethreemetalswereapplied,separately,atfivedifferentlevelsthatwere:Cdat5,15,30,60,and100μgg^-1;Pbat100,200,300,450and600μgg^-1andZnat50,100,150,200and250μgg^-1soil,InComparisontouncaontaminatedsoil,themicrobialbiomasscarbonandbiomassnitrogendecreasedsharplyinsoilscontaminatedwithCd,PbandZn,AmoreconsiderableincreaseinthemicrobialbiomassC:Nratiowasobservedinthemetalcontaminatedsoilsthanthenon-treatedcontrol.Amongthetestedmetals,CddisplayedthegreatestbiocidaleffectfollowedbyZnandPb,showintheirrelativetoxicityintheorderofCd>Zn>Pb.

简介：贫毛类环虫在在benthic食物网以及在红树属植物沼泽地的滋养的骑车和精力流动起一个重要作用。然而，他们一直不是当广泛地作为象polychaetes，腹足动物，瓣鳃类，和甲壳纲的动物那样的另外的macrofaunal组学习了。在假设下面，那贫毛类环虫密度和生物资源在中国的副热带的红树属植物沼泽地服从特定的地理分发模式，我们在Quanzhou海湾，Zhangjiang河口和Gaoqiao红树属植物的Luoyang河口调查了这二个参数沼泽地。在贫毛类环虫密度的一个地理坡度在Aegicerascorniculatum和Kandeliaobovata产地是在场的，它由此从更低的纬度减少了到更高的纬度。进一步，贫毛类环虫分发上的ANOVA测试表明贫毛类环虫密度和生物资源被区域，季节和区域显著地影响吗？

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简介：各种各样的过程残余表示一种生物资源资源已经专注但是像60wt.%一样包含水。这些材料通常被当作废物或简单地combusted直接产生热。最近，我们试图把他们变换成中间的热量的气体代替天然气，作为为先进燃烧实用程序的化学药品或高等级的气体的燃料。如此的变换通过双使流体化的床气化(DFBG)被实现。有关燃料的高水位线内容，DFBG被建议从字符气化并且焦油/烃改过完成任何一个，高效率的燃料或燃料drying/pyrolysis的直接去耦预先弄干。与燃料弄干一起，基于钙的催化剂能被使妊娠进燃料，没有另外的费用，到增加燃料的气化反应并且减少焦油形成。这篇文章在气化反应和焦油抑制能力上报导Ca受精方法和它的产生效果。同时，直接气化的原则有decoupled的湿燃料双使流体化的床气化(D-DFBG)也被加亮。