简介：Availablewaterandfertilizerhavebeenthemainlimitingfactorsforyieldsofspringwheat,whichoccupiesalargeareaoftheblacksoilzoneinnortheastChina;thus,theneedtosetupappropriatemodelsforscenarioanalysisofcroppingsystemmodelshasbeenincreasing.ThecapabilityofCropSyst,acroppingsystemsimulationmodel,tosimulatespringwheatgrowthofawidelygrownspringcultivar,'Longmai19',intheblacksoilzoneinnortheastChinaunderdifferentwaterandnitrogenregimeswasevaluated.Fielddatacollectedfromarotationexperimentofthreegrowingseasons(1992-1994)wereusedtocalibrateandvalidatethemodel.Themodelwasrunfor3yearsbyprovidinginitialconditionsatthebeginningoftherotationwithoutreinitializingthemodelinlateryearsintherotationsequence.CropinputparametersweresetbasedonmeasureddataortakenfromCropSystmanual.Afewcultivar-specificparameterswereadjustedwithinareasonablerangeoffluctuation.TheresultsdemonstratedtherobustnessofCropSystforsimulatingevapotranspiration,abovegroundbiomass,andgrainyieldof'Longmai19'springwheatwiththerootmeansquareerrorsbeing7%,13%and13%oftheobservedmeansforevapotranspiration(ET),grainyieldandabovegroundbiomass,respectively.AlthoughCropSystwasabletosimulatespringproductionreasonablywell,furtherevaluationandimprovementofthemodelwithamoredetailedfielddatabasewasdesirableforagriculturalsystemsinnortheastChina.

简介：持续农业生产具有到食物供应安全的重要重要性。这研究试图在北方中国平原(NCP)并且随后在县规模调查庄稼收益反应到土壤质量的空间可变性导出关键土壤质量指示物。土壤样品从表面(020厘米)在2008引用geo、拿并且表面下(2040厘米)在整个Fengqiu县的132块地里的层，在NCP的中心定位了，为随后的土壤性质的分析。年度庄稼收益从土壤样品是镇定的一样的领域被获得。土壤质量与13个土壤性质基于一个模糊集合被评估，并且它的空间分布被集成geostatistical分析和地理信息系统(GIS)调查技术。土壤质量索引被分类进五个等级，并且他们的空间分布在县以内被印射。表面土壤质量比表面下的土壤高是大约一～二个等级。质量索引因为表面和表面下的土壤断然与年度庄稼收益被联系，建议两个的重要性。土壤有机物，全部的氮，可得到的P，和可得到的K贡献了50%联合重量到土壤质量索引并且以可持续性在区域作为土壤质量地位的关键指示物被识别。

简介：在南部的中国的大米小麦旋转被经常的排干洪水的水政体和重氮(N)授精描绘。有进溶解的器官的氮的行为的研究的实质的缺乏(穿上)在强烈地管理的agroecosystem。在situ地实验3年的A被进行决定穿上沥滤并且它在6个连续大米/小麦季节由授精，灌溉和降水影响了的季节、每年的变化。在常规N实践下面(300kgN哈为米饭和200kgN的−1哈为小麦的−1)，季节的一般水准在leachate(100厘米土壤深度)穿上集中因为三个米饭和小麦季节是0.6–1.1和0.1–2.3mgNL−1,分别地。累积穿上沥滤被估计是1.1–2.3kgN哈为米饭季节和0.01–1.3kgN的−1哈为小麦季节的−1，与1.1–3.6kg的一个年度总数N哈−1。在大米季节，N化肥有小效果(P>0.05)在上穿上沥滤；降水和灌溉进口了3.6–9.1kgN哈−1穿上，它可以因此隐藏授精效果在上穿上。在小麦季节，N授精有积极效果(P<0.01)在上穿上。不过，这提升效果被可变降水强烈影响，它也带了1.8–2.9kgN哈−1穿上进地。尽管有到使用的化学N和大变化的一个很小的比例，走水路驾驶政体，穿上沥滤必然与另外的自然生态系统相比由于它的相对更大的数量在大米小麦旋转涉及综合的地N预算。

简介：Nitrogen(N)lossesfromammoniumbicarbonateorureaappliedtowheatandthenfollowedimmediatelybyirrigationwereinvestigated.Ammoniavolatilizationwasdeterminedbyamicrometeorologicalmethod(ammoniasampler),totalNlosswasestimatedbythe^15Nmassbalancemethod,anddenitrificationlosswasmeasuredbythediferencemethod(calculatedfromthedifferencebetweenthetotalNlossandammonialoss)andadirectmethod(measuringtheemissionof(N2+N2O)-^15N).Totalammonialossesfromammoniumbicarbonateandureain33dayswere8.7%and0.9%oftheappliednitrogen,respectively.ThecorrespondingtotalNlosseswere21.6%and29.5%,Apparentdenitrificationlosses(bythedifferencemethod)wereratherhigh,being12.9%fromammoniumbicarbonateand28.6%fromurea.However,noemissionof(N2+N2O)-^15Nwasdetectedusingthedirectmethod.

简介：Asequentialextractionmethodforthefractionationofphosphorus(P)inlakesedimentswasusedtoanalyzephosphorusfractionsofsedimentstakenfromthreelarge,shallow,eutrophicfreshwaterlakesofChina-TaihuLake,ChaohuLake,andLongganLake.AllthreelakesarelocatedinthelowerreachesoftheChangjiangRiver(YangtzeRiver).InTaihuLakeandChaohuLake,algaebloomsoccurredeveryyear,whileLongganLakewasamacrophyte-dominatedlake.Resultsshowedthatexchangeablephosphorusfractionsweremuchhigherintheeutrophiclakesedimentsthaninthemacrophyte-flourishinglakesediment.Also,theratioofFe:Pinthesedimentsofthealgae-predominantlakeswasgenerallymuchlowerthanthatinthemacrophyte-predominantlakes.Thus,thegeochemicalfractionsofphosphorusinsedimentshadacloserrelationshipwiththetypeofaquaticvegetation.

简介：Astudyonbalancedfertilizationwasconductedbymeansoflong-termfieldexperiments,andaconve-nienttableforbalancedfertilizationwascompiled.Theexperimentalresultsabouttheeffectoffertilizationonwateruseefficiencyofuplandwheatshowedthattheinputofinorganicfertilizershouldbereducedindryyears.

简介：泥土矿物质捱过是到植物的营养素的来源。Palygorskite是通常发生在干旱区域的土壤和沉积的一种Mg富有的含纤维的泥土矿物质。尽管许多研究检验了为palygorskite的形成和稳定性要求的环境条件，在根地区的这种矿物质的转变的信息(或根围)农业庄稼被限制。这研究在小麦和燕麦的根围探索了palygorskite转变的可能性并且比较了这些庄稼的能力从palygorskite提取结构的Mg。庄稼在从Hamadan区域，伊朗和佛罗里达palygorskite由沙的混合物组成的壶被栽培，与提取的水灌溉了，并且与完全或Mg免费的滋养的答案对待。在100d以后，由庄稼的Mg举起被测量。在每个壶的泥土大小的粒子也与沙被分开并且通过X光检查衍射(XRD)被分析。粒子的X光检查模式与纯palygorskite粒子的相比(在耕作前)。结果证明palygorskite能在与Mg免费的滋养的答案供应的壶为小麦的生长提供足够的Mg。尽管有由从palygorskite结构的两植物的镁举起，显示palygorskite的转变的可检测的山峰都没被XRD认出。在山峰紧张的1.05nm的减少为包含palygorskite的壶是更明显的并且比为与完全的滋养的答案灌溉的壶与Mg免费的滋养的答案灌溉了。尽管在山峰紧张的减少比小麦为燕麦是更大的，显示由燕麦捱过的更大的palygorskite，由燕麦的Mg举起是低的由观察的缺乏症状证实了。

简介：Excessivenitrogen(N)fertilizerapplicationtowinterwheatisacommonproblemontheNorthChinaPlain.TodeterminetheoptimumfertilizerNrateforwinterwheatproductionwhileminimizingNlosses,fieldexperimentswereconductedfortwogrowingseasonsateightsites,inHuiminCounty,ShandongProvince,from2001to2003.TheoptimumNrateformaximumgrainyieldwasinverselyrelatedtotheinitialsoilmineralNcontent(Nmin)inthetop90cmofthesoilprofilebeforesowing.TherewasnoyieldresponsetotheappliedNatthethreesiteswithhighinitialsoilmineralNlevels(average212kgNha-1).TheaverageoptimumNratewas96kgNha-1forthefivesiteswithlowinitialsoilNmin(average155kgNha-1)beforesowing.ResidualnitrateNinthetop90cmofthesoilprofileafterharvestincreasedwithincreasingfertilizerNapplicationrate.TheapparentNlossesduringthewheat-growingseasonalsoincreasedwithincreasingNapplicationrate.TheaverageapparentNlosseswiththeoptimumNrateswerelessthan15kgNha-1,whereasthefarmers'conventionalNapplicationrateresultedinlossesofmorethan100kgNha-1.Therefore,optimizingNuseforwinterwheatconsiderablyreducedNlossestotheenvironmentwithoutcompromisingcropyields.

简介：一个温室实验被进行为稍微高效的沙的泥土沃土土壤的滋养的地位改正测试并且比较盐的堆肥和盐的灌溉水的适用性，为了学习macronutrient利用和小麦(Triticumaestivumc.vGemmiza7)的干燥的事生产，在修改土壤环境并且到成长在土壤生产率上决定堆肥和盐的灌溉水的效果。沙的泥土沃土土壤与五率的堆肥被对待(0，24，36，48，和60m3ha−1，等价于0，3，4.5，和6gkg−1土壤，分别地)并且四咸度的灌溉水铺平(0.50(自来水)，4.9，6.3，和8.7dSm−1)。结果显示在收获，土壤的电的传导性(EC)是显著地(P<0.05)作为与控制相比由堆肥应用程序变化了。一般来说，土壤咸度显著地与增加堆肥的申请率增加了。可溶的盐，K，Cl，HCO3，Na，Ca，和Mg，被堆肥处理显著地增加。土壤钠吸附比率(SAR)被灌溉水的咸度层次显著地影响，并且显示出细微回答到堆肥申请。器官的碳内容也是的土壤显著地(P<0.05)由堆肥的申请影响了，与31.03g的最大的价值，kg−1以60m3ha−1的堆肥率和8.7dSm−1的灌溉水咸度水平和在控制观察的12.05gkg−1的最小的价值记录了。堆肥申请在小麦射击产生了显著增加干燥的事生产。最大的干燥的事生产(75.11gpot−1)与60m3ha−1堆肥和正常灌溉水发生了，与没有在8.70dSm−1的咸度水平的堆肥和灌溉水的增加的最少19.83gpot−1。K，N，P，Na，和Cl的小麦射击内容的重要增加与堆肥的增加被观察。相对高的射击N值可以被归因于堆肥应用程序引起的测试土壤的N可获得性的增加。同样，Na和Cl的射击内容的重要增加可以被归功于到土壤的增加可溶的K和Cl。自从堆肥供应的P在P溶解度是很低的盐、碱的土壤可能是负责的，射击P，N，和K的�

简介：钾(K)在植物影响生理的过程的一个范围并且是控制庄稼生产率和收益质量的一个关键因素。很少信息都不有关切割花植物的功能上的K营养的效果是可得到的。现在的学习被执行调查在K和N营养之间的相互作用，在花数量和毛莨属asiaticusL的质量上。植物与Kfertigation的三个层次被供应(60，120，或180mgKL−；1)不到50mgNL−；1应用，并且在120mgKL−的中间的水平；1，到N应用的三个层次(50，100，或150mgNL−；1)。二最低K治疗和最低N治疗由于更低的发生在花生产为佼佼者倒下茎，在很快扩展花茎的纸巾与局部性的Ca缺乏联系的混乱。有害效果在180mgKL−的供应下面已经以收益质量是明显的；1和50mgNL−；1，并且没在渗透的潜在的、相对的水内容或植物织物的膜稳定性与变化被联系，或与在除在高N申请下面的减少的Ca以外的叶子的矿物质内容的变化。我们的结果建议R的一个低营养的要求。asiaticusL。为K和N，在在K和N的高集中的申请下面的减少的花质量的织物水关系的参与的缺乏，和茎由Ca的减少的可获得性在N和K的高申请下面倒下到花的膨胀织物的正式就职起源。

简介：Soilqualityassessmenthasbeensuggestedasaneffectivetoolforevaluatingsustainabilityofsoilandcropmanagementpractices.Theobjectiveofthisstudywastodevelopasensitivesoilqualityindex(SQI)basedonbulkdensity(BD),water-holdingcapacity(WHC),water-stableaggregates(WSA),aggregatemeanweightdiameter(AMWD),totalorganicC(TOC)andCinputtoevaluatetheimportantrice-wheatcroppingsystemonanInceptisolinIndia.Along-termexperimenthasbeenconductedfor18yearsattheIndianCouncilofAgriculturalResearch-IndianInstituteofFarmingSystemsResearch,Modipuram,India.Thetreatmentsselectedforthisstudywerecomprisedofano-fertilizercontrolandN,PandKfertilizers(NPK)combinedwithZnandSfertilizers(NPK+Zn+S),farmyardmanure(NPK+FYM),greengramresidues(NPK+GR)andcerealresidues(NPK+CR),laidoutinarandomizedcompleteblockdesignwiththreereplications.SoilsampleswerecollectedandanalyzedforBD,WHC,WSAandTOC.Correlationanalysisrevealedthatbothriceandwheatyieldssigni?cantlyincreasedwiththeincreasesinAMWD,TOCandCinput,butdecreasedwiththeincreaseinBD.TheSQIvalueswerethengeneratedbasedonregressionanalysisofBD,WSA,AMWD,TOCandCinputwithriceandwheatyieldsforthe0–15and15–30cmsoillayers,respectively.RegressionanalysesbetweencropyieldsandSQIvaluesshowedaquadratictypeofrelationwiththecoeffcientofdetermination(R~2)varyingfrom0.78to0.89.Withregardtosoilsustainability,applyingcropresiduestobothriceandwheatcouldmaintainsoilqualityforalongerperiod,whereasthehighestyieldsofboththecropswererecordedintheNPK+Zn+Streatment.Theregressionequationsdevelopedinthisstudycouldbeusedtomonitorsoilqualityinasubhumidtropicalrice-wheatcroppingsystem.

简介：Humanactivitiesmakestrongeffectsonsoilformation.AnthropogenicsoilsaremuchmoreintensiveandextensiveinChinafortheirhistoryofagriculturalproductioncanbedatedbacktomorethan7000yearsagoOwingtodifferentphysicalconditionsandlanduses,theanthropogenicsoil-formingprocessesarevariousAnthrosolsareproposed,andthecorrespondingsoilorderissetupinChineseSoilTaxonomy(CST),Mainlybasedon6Anthropogenicdiagnostichorizons,whichareanthraquicepipedon,hydragrichorizon,irragricepipedon,cumulicepipedon,fimicepipedonandagrichorzon,theAnthrosolsOrderissubividedinto2soilsubordersand4soilgroups.MeanwhiletheclassificationofAnthrosolsinCSThasbeenbasicallyacceptedastheclassificationofAnthrosolsinWorldReferenceBaseforSoilResources(WRB).

简介：在东南亚洲的蔬菜生产经常是依次与充满的米饭。有充满的大米生产的土壤的puddling可以为干燥土地庄稼的随后的生产导致不利土壤条件。为了证实永久蔬菜生产是否导致赞成土壤，在充满的大米在一个2年的地实验被学习以后，在土壤性质上与充满的大米依次为蔬菜，五个不同永久蔬菜生产系统的效果和蔬菜生产的一个系统调节。在0.05–0.10m深度层的体积密度与充满的米饭依次与永久蔬菜生产和蔬菜生产减少了。减少大批，密度被器官的粪肥和米饭外壳的申请影响，并且特别由庄稼的数字栽培了建议土壤耕种的那频率穿上主要效果体积密度。在在有提起的床的建设的联合，充满的米饭能在土壤结构上减少或完全消除puddling的否定效果以后，与公牛拖拉耕作。在0.15–0.20m土壤深度的体积密度没被影响。土壤酸味在所有系统显著地减少了。器官的碳在所有系统增加了的土壤，而是重要增加仅仅在二个永久蔬菜生产系统被发现。可得到的磷(P)显著地在二个永久蔬菜生产系统增加了，与一断然，到P的数量的关联适用。重要减少大批在pH的密度和增加(H2O)在仅仅2年以后，证明在充满的米饭以后的土壤条件能在集中的蔬菜下面在一短时间被改进生产。

简介：Anincubationexperimentwascarriedoutinlaboratorytostudytheeffectoftemperature,moisture,phosphorus,organicmatter,croppingandpreviouselementalsulfurapplicationonelementalsulfuroxidationinfourselectedsoils,fluvo-aquicsoil,blacksoil,yellow-brownsoilandredsoil,Inallthesoilstested,sulfuroxidationratewasinfluencedbytemperatureandthetemperaturecoefficient(Q10)valuesattherangefrom10to30℃were4.41,,6.19and3.71forthefoursoils,respectively.Therateofsulfuroxidationwasparabolicallyrelatedtosoilwatercontent.Theoptimummoisturecontentforthemaximumoxiationratewasdifferentamongsoils,Phosphorusincreasedtheoxidationrateofelementalsulfurby57.7%,33.1%,21.7%and26.4%fortheabovefoursoils,respectively,comparedwiththecontrol(nophosphorusapplied).Organicmaterialofcornstrawwhichwasgoundandpassedthrougha0.5-mmsievealsoincreasedthoxidationrateofelementalsulfurinthefoursoilsby59.8%,7.8%,39.2%and540.4%,respectively.Elementalsulfurwhichwasappliedpreviouslytosoilssignificantlyenhancedtheoxidationofelementalsulfursubsequentlyaddedandincreasedsulfur-oxidizingpopulationssuchasautotrophicelementalsulfuroxidizerswithpHoptimum6.8,autotrophicthiosufateoxidizerswithpHoptimum6.8,heterotrophicthiosulfateoxidizersandheterotrophicsulfateproducers.Croppinghadlittleeffectonelementalsulfur-oxidizingpotentialityofsoils.

简介：Organicamendmentssuchasvermicompostandbiocharhavebeenreportedtoenhancesoilfertilityandcropproductivity.However,whethertheco-applicationofbothamendmentshassynergisticeffectsorwhethersuchbenefitsareaccompaniedbytheriskofgaseousnitrogen(N)lossinanagroecosystemremainsunknown.Asoilcolumnexperimentwithafullyfactorialdesignwasconductedusingthreelevelsofvermicompost(nodose,lowdose(1%,weight:weight),andhighdose(3%,weight:weight))withoutorwithbiochar(1%,weight:weight)toinvestigatetheireffectsonricegrowthandgaseousNlossacrossthecropgrowingseason.Ourresultsdemonstratedthatsynergisticinteractionsexistedbetweenvermicompostandbiocharinpromotingcropyield.Comparedwithbiocharamendmentalone,biocharcombinedwithvermicompostsignificantly(P<0.01)increasedriceyieldby26.5%–35.3%.However,highdoseofvermicompostsignificantly(P<0.01)increasedthecumulativeammonia(NH3)andnitrousoxide(N2O)emissions.Inthepresenceofvermicompost,theincorporationofbiocharamendmentsignificantly(P<0.01)decreasedthecumulativeN2Oemissionby14.1%–18.6%.ThelowestemissionfactorvalueofNH3andN2Owasachievedusingbiocharincombinationwithlowdoseofvermicompost.Thisstudyrevealedthatthecombinationofbiocharandmoderatedoseofvermicompostoffersanovelapproachtopromotecropproductivitywhilereducingtheenvironmentalrisk.

简介：Duetothegrowingconcernabouttheagriculturalphosphorus(P)lossespollution,anin-depthunderstandingofPinpaddysoilsofChinawouldbehelpfulinprovidinganationalperspectiveoftheenvironmentalimpactofPcyclingandfertilityonChina'sfarms.Inthisstudy,weevaluatedthePstorageandthePdensityofpaddysoilsinChina,characterizedthespatialvariationsofPamongthesubgroupsofpaddysoilsandsoilregionsinChina,andevaluatedthePdatausingGIS-basedanalysis,whichincludedanewlycompiled1:1000000digitalsoilmapofChina,andusing1490soilprofiles.TheavailableandtotalPdensitiesofpaddysoilswere6.7and698.5gm-3,respectively.OverallinChina,thetotalPstoragewithin1mofpaddysoilswasestimatedtobe330.2Tg.ThePdensityofpaddysoilsvariedsubstantiallywithsubgroupsduetothedifferentsoilwaterregimessuchasgroundwatertableandsoildrainage.ThePavailabilityinpaddysoils,especiallyinsurfacelayer,washigherinhightemperatureandprecipitationareas.Furtherresearchisneededtoexaminemoreanthropogenicimpactfactors,suchasincreasinguseofchemicalfertilizer.

简介：ThesoilsinSouthChinaseaIslands(SCSI)weredividedintothreetypes,nmaely,phospho-calcsoils,skeletisolsandcoasticsolonchake,whichwerederivedfrombio-clasticandstronglycalcareoussediments.Incomparisonwiththeirparentmaterials,thephospho-CalcsoilshavehighercontentsofP,ZnCu,Ba,andCd,whichtendtoincreasegraduallywithtime,andlowercontentsofMg,Ca,Sr,B,V,Pb,andMo,whichtendtodecreasebydegreeswithtime,Theabove-mentionedconstituentsinskeletisolsandcoasticsolonchaksaresimilartothoseintheirparentmaterialsexceptforPandNa,Thefactorsaffectingelementdistributionaremainlyspecialbioclimateandparentmaterial,meanwhile,resultingintheremakableinfluenceonelementdistributionthroughsoil-formingtime.

简介：ThecurrentstatusofchemicalfertilizersproductionandconsumptioninChinaaswellastheirimportantrolesinChinesemodernagriculturearediscussedwithspecialconcernstotheenvironmentalissuesrelatedtochemicalfertilizeruse.Ontheonehand.thetotalamountofchemicalfertilizerproducedisinsufficienttomeettheagriculturalneeds.Ontheotherhand.theproductionandconsumptionofchemicalfertilizersinChinaareobviouslynotbalanced.Insomeareasoverapplicationofnitrogenfertilizersandlossofphosphatefertilizerduetosoilerosionhaveresultedinsomeundesirableenvironmentalproblemssuchasincreaseofnitrateinwaterandeutrophicationofwaterbodies.Maximumscientificusesoforganicmanuresincombinationwithreasonableuseofchemicalfertilizersarepartofgoodpracticesnotonlyinincreasuingsoilproductivityandkeepingsustainableagriculturedevelopmentbutalsoinminimizingtheirdetrimentaleffectsontheenvironment.

简介：

简介：心土酸味限制根生长并且在世界的许多部分减少庄稼收益。多于氮(N)在庄稼生产使用了的化肥的一半是当前输了到环境。这研究试图在到没有为止玉米(ZeamaysL.)在N化肥的效率上调查石膏申请的效果在南部的巴西的生产。一个地实验检验了适用表面的石膏的效果(0，5，10，和15Mg哈1)和穿衣顶的铵硝酸盐(NH4没有3)(60，120，和180kgN哈玉米根长度，N举起，和谷物产量上的1)。一个温室实验用从地实验地点收集不评估3-N与适用表面的石膏沥滤，N举起，和根长度的没受到干扰的土壤列被进行(0和10Mg哈1)和穿衣顶的NH4没有3(0和180kgN哈1)。心土酸味的改善由于石膏申请，增加的玉米根生长，N举起，谷物收益，和N使用效率。到土壤表面的适用的石膏由19%-38%和N的部分因素生产率增加了玉米谷物产量(PFP由27%-38%的N)，取决于N申请率。没受到干扰的土壤列温室实验的结果证明由石膏申请的N使用效率的那改进由于从在由于增加的玉米根长度的心土的没有3-N的更高的N举起。我们的结果建议有在一个到没有为止玉米系统的石膏的那改善心土酸味能增加N使用效率，改进谷物产量，并且减少由于沥滤的没有3-N的环境风险。