简介：TheadsorptionkineticsofPb^2+ondifferentsoilsandmineralswithvariablechargeswasstudiedbythetwoion-selectiveelectrodetechniqueatdifferentpHandconcentrations.Theresultsshowedthatmorethan95%ofadsorptiononallthesamplesoccurredduringthefirst5minutes.Alladsorptiontime-dependentdatacouldfitthesurfacesecond-orderequationverywell.ThevaluesofXmweregoethite>kaolinite,andlatosol>redsoilatthesameinitialreactionconcentration.Thevaluesofkwerekaolinite>>goethite,andlatosol>redsoilatthesamereactionpHandinitialconcentration.ThehigherthesuspensionpH,thefastertheadsorptionoccurred.ThemeaningofXmgotbythetwoion-selectiveelectrodetechnique(onekindofbatchtechnique)wasdifferentfromthatbythemiscibledisplacementtechniqueinthattheformerwasonlytheequilibriumadsorptionamountatadefiniteconcentrationandpH,butthelatterwasalmostequaltotheadsorptioncapacityatadefinitepHwithmuchlessinfluenceofconcentration.OnePb^2+wassupposedtooccupytwoadsorptionsitesastheadsorptionmechanismisconcerned.

简介：钴(公司)在自然地发生在重要数量存在锰(Mn)氧化物并且改变Mn氧化物晶体的生长。四分层的Mn氧化物，Na-buserite(Na公共汽车)并且三共同做从Mn的氧化准备的Na-buserite样品(哦)2与5%，10%，和20%Co/(Mn+公司)臼齿的比率(5Co-Na-bus，10Co-Na-bus，和20Co-Na-bus)，被用来准备todorokite，地球的表面上的普通Mn氧化物，把Mg2+/Co2+离子用作一个模板。结果证明todorokites能被交换Mg2+的非做的Na-buserite的倒流处理获得，三共同做在气压的Na-buserites。然而，todorokites的形成被交换Co2+的Na公共汽车，5Co-Na-bus，和10Co-Na-bus样品的倒流处理禁止。相反，todorokite被交换Co2+的20Co-Na-bus样品的倒流处理在气压下面获得。X光检查光电子光谱学分析证明做的公司在做的Na-buserites的MnO6层作为Co3+存在。在MnO6层的代替的Co3+的数量可以作为一个模板用Co2+离子在buserite的变换起一个关键作用到todorokite。

简介：ForestmanagementisexpectedtoinfluencesoilCO2efflux(FCO2)asaresultofchangesinmicroenvironmentalconditions,soilmicroclimate,androotdynamics.SoilFCO2ratewasmeasuredduringthegrowingseasonof2006inboththinningandnon-thinninglocationswithinstandsrangingfrom0to8yearsafterthemostrecentthinninginChinesefir(Cunninghamialanceolata(Lamb.)Hook)plantationsinHuitongEcosystemResearchStation,Hunan,China.SoiltemperatureandmoisturewerealsomeasuredtoexaminerelationshipsbetweenFCO2andsoilproperties.ForestthinningresultedinhugechangesinFCO2thatvariedwithtimesincecutting.Immediatelyfollowingharvest(year0)FCO2inthinningareaincreasedbyabout30%,declinedto20%–27%belowpre-cuttinglevelsduringyears4–6,andrecoveredtopre-cuttinglevelsat8yearspost-cutting.Asimilartemporalpattern,butwithsmallerchanges,wasfoundinnon-thinninglocations.TheinitialincreaseinFCO2couldbeattributedtoacombinationofrootdecay,soildisturbance,andincreasedsoiltemperatureingaps,whilethesubsequentdecreaseandrecoverytothedeathandgradualregrowthofactiveroots.StrongeffectsofsoiltemperatureandsoilwatercontentonFCO2werefound.ForestthinningmainlyinfluencedFCO2throughchangesintreerootrespiration,andthenetresultwasadecreaseinintegratedFCO2fluxthroughtheentirefellingcycle.

简介：从土壤表面的二氧化碳(CO2)的流动在陆上的生态系统介绍碳(C)周期的一个重要部件并且被很多个关於生命、不能生活的因素控制。以便更好在副热带的森林里理解土壤CO2流动(FCO2)的特征，土壤FCO2率在五种邻近的森林类型被确定(樟脑树森林，马森松森林，混合樟脑树和马森消瘦森林，中国香甜的口香糖森林，并且猛砍松森林)在在长沙的Tianjiling国家公园，湖南省在副热带的中国，从1月到2010年12月。土壤温度(Tsoil)的影响，容量的土壤浇内容(土壤)，玷污pH，玷污器官的碳(SOC)并且玷污土壤FCO2率上的C/nitrogen(N)比率也被调查。年度吝啬的土壤FCO2率与森林类型变化了。土壤FCO2率在樟脑树森林里是最高的(3.53瑮楲畢楴湯?潴琠敨猠楯??中?湡?桴瑡倠?灡汰捩瑡潩?污潳愠捣汥牥瑡摥???牴湡晳牯慭楴湯椠?潳汩猠飼?飼吗？？

简介：Natural^15NabundancemethodwasusedinthisstudytoinvestigatetheN2-fiingcapacitiesofseveralherbaceousandshrublegumesbyafieldexperiment,Forherbaceouslegumes,theresultswereinconsistentwiththoseobtainedbyapotexperiment.CrotalariamucronataDesv.hadahigher,N2-fixingcapacitythanVignasinensis(L.)Savi.Forshurublegumes,N2-fixingCapacityunderfieldconditionwasslightlydifferentfromthatinpotexperiment.Theseresultsdemonstratedthatthenatural^15NabundancemethodwasapplicabletoevaluatingN2-fixingcapacitiesofherbaceousandshrublegumes,andthatpotexperimentwassuitableforevaluatingtheN2-fixingcapacitiesofnotonlyherbaceouslegumesbutalsoshrublegumes.LeguminousN2-fixingplantsdifferedinresponsetophosphorusfertilization,Phosphorusfertilizerappicationgreatlyincreasedthepercentageofnitrogenderivedfromair(%Ndfa)andtotalamountofN2fixedbyLespedezformosa(Vog.)Koehne(Jiangxi),PhosphorusfertilizershowednosignifcanteffectontheN2-fixingpercentageofCajanuscajan(L.)Millsp.butincreaseditstotalbiomass,thusincreasingthetotalamountofN2fixed.

简介：AfieldexperimentwasconductedonChinesecabbage(BrassicacampestrisL.ssp.pekinensis(Lour.)Olsson)inaNanjingsuburbin2003.Theexperimentincluded4treatmentsinarandomizedcompleteblockdesignwith3replicates:zerochemicalfertilizerN(CK);ureaatratesof300kgNha-1(U300)and600kgNha-1(U600),bothasbasalandtwotopdressings;andpolymer-coatedureaatarateof180kgNha-1(PCU180)asabasalapplication.Theacetyleneinhibitiontechniquewasusedtomeasuredenitrification(N2+N2O)fromintactsoilcoresandN2Oemissionsintheabsenceofacetylene.ResultsshowedthatcomparedtoCKtotaldenitrificationlossesweresignificantlygreater(P≤0.05)inthePCU180,U300,andU600treatments,whileN2OemissionsintheU300andU600treatmentsweresignificantlyhigher(P≤0.05)thanCK.IntheU300andU600treatmentspeaksofdenitrificationandN2OemissionwereusuallyobservedafterNapplication.Inthepolymer-coatedureatreatment(PCU180)duringtheperiod20to40daysaftertransplanting,higherdenitrificationratesandN2Ofluxesoccurred.Comparedwithurea,polymer-coatedureadidnotshowanyeffectonreducingdenitrificationlossesandN2OemissionsintermsofpercentageofappliedN.Astemperaturegraduallydecreasedfromtransplantingtoharvest,denitrificationratesandN2Oemissionstendedtodecrease.Asignificant(P≤0.01)positivecorrelationoccurredbetweendenitrification(r=0.872)orN2Oemission(r=0.781)fluxdensitiesandsoiltemperatureintheCKtreatmentwithastablenitratecontentduringthewholegrowingseason.

简介：Aridsoilswherewaterandnutrientsarescarceoccupyover30%oftheEarth’stotalsurface.However,themicrobialautotrophyintheharshenvironmentsremainslargelyunexplored.Inthisstudy,theabundanceanddiversityofautotrophicbacteriawereinvestigated,byquantifyingandprofilingthelargesubunitgenesofribulose-1,5-bisphosphatecarboxylase/oxygenase(RuBisCO)formI(cbbL)responsibleforCO2fixation,inthearidsoilsunderthreetypicalplanttypes(Haloxylonammodendron,Cleistogeneschinensis,andReaumuriasoongorica)inNorthwestChina.Thebacterialcommunitiesinthesoilswerealsocharacterizedusingthe16SrRNAgene.Abundanceofred-likeautotrophicbacteriarangedfrom3.94×105to1.51×106copiesg-1drysoilandthoseofgreen-likeautotrophicbacteriarangedfrom1.15×106to2.08×106copiesg-1drysoil.Abundanceofbothred-andgreen-likeautotrophicbacteriadidnotsignificantlydifferamongthesoilsunderdifferentplanttypes.TheautotrophicbacteriaidentifiedwiththecbbLgeneprimerweremainlyaffiliatedwithAlphaproteobacteria,Betaproteobacteriaandanunculturedbacterialgroup,whichwerenotdetectedinthe16SrRNAlibrary.Inaddition,25.9%and8.1%ofthe16SrRNAgeneswereaffiliatedwithCyanobacteriainthesoilsunderH.ammodendronandR.soongorica,respectively.However,noCyanobacteria-affiliatedcbbLgenesweredetectedinthesamesoils.TheresultssuggestedthatmicrobialautotrophicCO2fixationmightbesignificantinthecarboncyclingofaridsoils,whichwarrantsfurtherexploration.

简介：Biochar是生物资源热分解获得并且考虑了碳隐遁的一个平均数的一个充满碳的产品。在这研究，从食物与农业科学的学院的农场的沙的石灰质的土壤，绍德国王大学，沙特阿拉伯，与也被修改Conocarpus直立的L的木质的废物。(CW)或biochar(BC)以0的率(控制)从CW生产了，10，30和50gkg−1。土壤pH，溶解的器官的碳(文档)，微生物引起的生物资源碳(MBC)，公司2排放和新陈代谢的商上的修正案的效果(沙的石灰质的土壤的qCO2)在一个60-d孵化实验被学习。结果证明CW的增加与控制和BC的增加相比在土壤pH导致了重要减少。公司2-C排放率比孵化时间什么时候进行在孵化的开始几天内是更高的。特别以更高的率，从与CW修改的土壤的累积公司2-C排放更高(近似到6褶层的3-)与BC从控制和土壤比那修改了。修改BC的土壤证明因为与非修改的土壤，而是累积公司2-C的增加相比排放不在孵化的60d以后是重要的，公司2-C排放的重要增加在孵化的第一天期间评价。在另一方面，CW应用比控制和BC应用导致了更加更高累积的公司2-C排放，MBC和文档。与0白天的异常(在孵化的1h以后)，导致的CW和BC应用程序作为与控制相比降低qCO2的值。力量功能运动模型令人满意地描述了累积公司2-C排放。通常，公司2排放的最低价值与BC在土壤被观察，建议到公司2排放的BC的贡献作为与CW的相比很小。

简介：与一个改编微生物引起的社区接种土壤比有在bioremediation的纯紧张的接种是一条更有效的bioaugmentation途径。然而，从有在土壤补习改变污染层次和污染历史的地点的不同inocula的潜力的信息正在缺乏。学习的目的是在土壤inocula调查改编微生物的潜力，与不同污染层次和污染历史，到降级1,2,4-trichlorobenzene(1,2,4-TCB)。从污染chlorobenzene的地点的三不同土壤被接种进农业土壤和与1,2,4-TCB刺的土壤暂停文化。结果证明36.52%开始应用的1,2,4-TCB在非接种的土壤是在场的，而大约19.00%1,2,4-TCB在在28天孵化以后与污染土壤接种的农业土壤是在场的。与改编微生物引起的生物资源接种的土壤(在土壤inocula)比非接种的土壤显示出更高的呼吸和更低的1,2,4-TCB挥发，建议1,2,4-TCB的存在在为接种使用的污染土壤改编了degraders。它进一步在污染土壤暂停文化被证实无机的氯化物离子的集中在全部试验性的时期上连续地增加了。更高的降级潜力带到不仅而且到更高的残余形成的inocula的更高的污染。然而，甚至低级污染的inocula在提高1,2,4-TCB的降级是有效的。因此，适用改编了在土壤形式的微生物特别与更低的污染层次，inocula能是为土壤补习的有效、环境友好的策略。

简介：Anopen-topchamberexperimentwasconductedattheUniversityofMichiganBiologicalStationnearPellston,Michigan,USA,tostudytheeffectsofsoilfertilityandCO2onleaf,stemandrootdarkrespiration(Rd)ofPopulustremuloides.Overall,area-baseddaytimeleafRd(Rda)wassignificantlygreateratelevatedthanatambientCO2inhigh-fertilitysoil,butnotinlow-fertilitysoil.Mass-basedleafRd(Rdm)wasoverallgreaterforhigh-thanforlow-fertilitysoilgrowntreesatelevated,butnotatambientCO2.NighttimeleafRdaandRdmwereunaffectedbysoilfertilityorCO2,norwasstemRda,whichrangedfrom1.0to1.4μmolm-2s-1inthespringand3.5to4.5μmolm-2s-1inthesummer.RootRdawassignificantlyhigherinhigh-thaninlow-fertilitysoil,butwasunaffectedbyCO2.SincebiomassproductionofP.tremuloideswillbesignificantlygreateratelevatedCO2whilespecificRdwilleitherincreaseorremainunchanged,wepredictthatcarbonlosstotheatmospherethroughrespirationfromthisecologicallyimportantspecieswouldincreaseathigherCO2.SoilfertilitywouldalsointeractwithelevatedCO2inaffectingthecarbonflowintheplant-soil-airsystem.

简介：PotexperimentswerecarriedouttoestimateN2fixationbyvetch,milkvetch,sicklealfalfaandbroadbeaninpurestandusinga^15N-labelledsoil.Winterwheatwasusedasthenon-fixingcontrol.The15N-labelledsoilusedwaspreparedbygrowingcorn-wheat-cornsuccessivelyonanearlyorganic-matter-freeXiashuloesssupplementedwithadequateamountsof(15NH4)2SO4,P,Kandmicronutrients,thenincorporatingthese15N-labelledplantmaterialsintothesoilaftereachhavest,andallowingtheplantmaterialstobedecomposedaerobicallyfor410dafterincorporationoftheplantmaterialofthethirecrop.The15Nenrichmentofwheatplant-Nvariedslightlywithorgans,withamaximumdifferenceof9.8%,Basedon15NenrichmentofsoilNinferredfromthemeanvalueofthe15Nenrichmentindifferentorgansofwheat79%-91%oftotalNinthetopsand67%-74%oftotalNintherootsoflegumesstudiedwerederivedfromatmosphere.EstimatebyisotopedilutionmethodwasingoodagreementwiththatbytheconventionaldifferencemethodprovidedvaluesobtainedbythelatterwerecorrectedforseedN,andalsowiththatfromthemeasurementofNaccumulatedinthetopsofthelegumes.

简介：降水在半干旱、干旱的区域是生态系统函数和进程的主要驱动程序。在如此的水有限生态系统，搏动了水输入直接通过弄干的一系列土壤和重新弄湿的周期控制地下的过程。在土壤CO2流出上调查水的分散的增加的效果，一个人工的降水事件(3公里)在亩被用于一个荒芜的灌木生态系统我们在中国的Ordos高原的沙土地。土壤呼吸率在在这块地里增加水以后立即增加了2.84.1次，然后它在48h以内回到了背景水平。在实验期间，土壤CO2生产在2047.0和7383.0mgm之间?2。在灌木陆地，土壤呼吸回答显示出空间变化，有在比在interplant空格的灌木下面的更强壮的脉搏效果。土壤呼吸回答的空间变化仔细与土壤底层可获得性的异质被联系。除了降水，玷污器官的碳和全部的氮水池也在荒芜的生态系统作为土壤CO2损失的决定因素被识别。

简介：在2006年雨季,对北京密云水库库西试验区的人工林林冠层、枯落物层和土壤层的水文特征进行观测研究。结果表明：单次降雨过程中,林冠截留量、穿透降水量和树干茎流量占大气降水量的比例,油松人工林分别为8.46%～68.97%3、0.80%～90.63%和0.12%～1.62%,栎柏人工混交林分别为0.53%～29.35%6、8.48%～93.71%和2.17%～5.76%,2种林分的平均截留率分别为29.23%和18.21%,2种林分枯落物的最大持水量分别为1.51和1.76mm。油松人工林地0～30cm土层的最大贮水能力和有效贮水能力分别为204.90和68.23mm,栎柏人工混交林地的分别为160.80和41.87mm;油松人工林地和栎柏人工混交林林地的稳渗速率分别为0.68和0.22mm/min。

简介：麻竹（Dendrocalamuslatiflorus）是优良的笋材两用丛生竹种，研究立竹器官营养元素的吸收、积累和分配，可为麻竹林的土壤养分管理提供参考。通过对麻竹2年生立竹叶、枝、秆的氮（N）、磷（P）、钾（K）、钙（Ca）、镁（Mg）、铁（Fe）、锰（Mn）、锌（Zn）和铜（Cu）等9种营养元素含量进行测定分析，结果表明：试验麻竹林2年生立竹地上部分器官营养元素含量除Zn为枝＞叶＞秆外，其他8种营养元素含量均为叶＞枝＞秆，营养元素含量大小均为N＞K＞P＞Ca＞Mg＞Mn＞Fe＞Zn＞Cu。2年生立竹地上部分9种营养元素的积累量为249.13kg／hm^2，枝（106.25kg／hm^2）＞秆（82.01kg／hm^2）＞叶（60.87kg／hm^2），其中以N素的积累量最大，所占比例达61.0％；9种营养元素含量在地上部分器官中的分配比例为枝（37.0％）＞叶（35.9％）＞秆（27.1％）。建议在麻竹林经营过程需适当增施氮肥，促进竹林生长和效益产出。

简介：Theclosed-jarincubationmethodiswidelyusedtoestimatethemineralizationofsoilorganicC.TherearetwoCpools(i.e.,organicandinorganicC)incalcareoussoil.ToevaluatetheeffectofadditionalcarbonatesonCO2emissionfromcalcareoussoilduringclosed-jarincubation,threeincubationexperimentswereconductedbyaddingdifferenttypes(CaCO3andMgCO3)andamountsofcarbonatetothesoil.TheadditionofcarbonatessignificantlyincreasedCO2emissionfromthesoil;theincreaserangedfrom12.0%intheCaCO3amendedsoilto460%intheMgCO3amendedsoilduringa100-dincubation.CumulativeCO2productionattheendoftheincubationwasthreetimesgreaterintheMgCO3amendedsoilcomparedtotheCaCO3amendedone.TheCO2emissionincreasedwiththeamountofCaCO3addedtothesoil.Incontrast,CO2emissiondecreasedastheamountofMgCO3addedtothesoilincreased.Ourresultsconfirmedthattheclosed-jarincubationmethodcouldleadtoanoverestimateoforganicCmineralizationincalcareoussoils.BecauseofitseffectonsoilpHandthedissolutionofcarbonates,HgCl2shouldnotbeusedtosterilizecalcareoussoiliftheexperimentincludesthemeasurementofsoilCO2production.

简介：Theannualseriesofδ13CweremeasuredintreeringsofthreeCryptomeriafortuneidisks(CF-1,CF-2,andCF-3)collectedfromWestTianmuMountain,ZhejiangProvince,China,accordingtocross-datingtreeringages.Therewasnoobviousdecreasingtrendoftheδ13CannualtimeseriesofCF-2before1835.However,from1835to1982thethreetreeringδ13Cannualseriesexhibitedsimilardecreasingtrendsthatweresignificantly(P≤0.001)correlated.Thedistributioncharacteristicsofascatterdiagrambetweenestimatedδ13CseriesofCF-2frommodelingandtheatmosphericCO2concentrationextractedfromtheLawDomeicecorefrom1840to1978wereanalyzedandacurvilinearregressionequationforreconstructingatmosphericCO2concentrationwasestablishedwithR2=0.98.Also,atestofindependentsamplesindicatedthatbetween1685and1839thereconstructedatmosphericCO2concentrationusingtheδ13CseriesofCF-2hadacloserelationshipwiththeLawDomeandSipleicecores,withastandarddeviationof1.98.ThegeneralincreasingtrendofthereconstructedatmosphericCO2concentrationcloselyreflectedthelong-termvariationofatmosphericCO2concentrationrecordedbothbeforeandaftertheIndustrialRevolution.Between1685and1840theevaluatedatmosphericCO2concentrationwasstable,butafter1840itexhibitedarapidincrease.Givenalongerδ13Cannualtimeseriesoftreerings,itwasfeasibletorebuildarepresentativetimeseriestodescribetheatmosphericCO2concentrationforanearlierperiodandforyearsthatwerenotintheicecorerecord.