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简介：Ahybridanalysismethodintimeandfrequencydomainsforlinearsoil-structureinteractionispresented.First,thetimedomainsolutionofthesystemwithRayleighdampingexcitedbyashorttimeimpulseisobtainedbythedecouplingnumericalsimulationtechniqueofnear-fieldwavemotion.Then,thecorrespondingfrequencydomainsolutioncanbegotbyFouriertransform.Accordingtotherelationshipbetweendampingvalueanddynamicre-sponseofasystem,thesolutionofthesystemwithcomplexdampingcanbegotbyTaylorexpansion.Thehybridmethodmakesthebestofdecouplingandexplicitalgorithmintimedomain,andincreasesthecalculationefficien-cyforlinearsoil-structureinteractionanalysis.

简介：WecollectedacornsfromselectedQuercusroburandQuercuspetraeamothertreesgrowingatstationswithdifferentdepthstothewatertable.Weproducedpairsofmicro-cuttingsfromthesesingleacorns.Theobtainedpairsofcuttingsrepresentedphenotypesofhighsimilarityaccordingtophotosyntheticparameters.Thesepairsofcuttingswereusedtotesttheplasticityofresponsetocontrastingwaterregimes.Foreachpair,onecuttingwassubmittedtodroughtandtheotherwassubmittedtowaterlogging.Droughtresponsewasrecordedaccordingtogasexchangetraits（stomatalclosureandwateruseefficiency）.TheresponsetowaterloggingwasrecordedaccordingtothecapacitytoformhypertrophiedlenticelsandtomaintaintheCO2assimilationrate.Intermediaryphenotypespresentingbothhighwateruseefficiencyandthecapacitytodevelophypertrophiedlenticelswereexpected.

简介：土壤水保留曲线(SWRC)提供在弄干与吸以浸透，水内容或空比率的度的变化弄湿过程的/期间描述不饱和的土壤的反应的一个重要工具。在产生这些曲线的关键考虑是怎么测量吸。经常，过滤器纸技术被采用，特别当高吸被开发时，例如与塑料泥土。当每大小与这种技术花至少一个星期，在弄干并且弄湿产生完整的SWRC能花月或年。在实验室张力计的开发现在允许矩阵吸直到要测量的大约1.5MPa。与如此的一台设备，由连续测量在小时或天为象淤泥和泥土那样的小粒的土壤开发SWRC是可能的。这份报纸描述被开发在三小粒的土壤弄干期间在体积，水内容和矩阵吸测量变化的试验性的安装。仪器的限制和曲线的实用性被讨论。

简介：Changesofsoilorganicnitrogenformsandsoilnitrogensupplyundercontinuousricecroppingsystemwereinvestigatedinalong-termfertilizationexperimentinJinhua,ZhejiangProvince,China.ThefertilizertreatmentsincludedcombinationofP-K,N-K,N-P,andN-P-Kaswellasthecontrol.Aftersixyearsofcontinuousdouble-ricecropping,totalsoilNandhydrolysableNcontentsremainedstableinplotswithNtreatments,whilethehydrolysableNcontentsweresubstantiallyreducedinthoseplotswithoutNapplication.Comparedtotheunbalancedfertilizationtreatments,PandKincreasedthepercentageofhydrolysableammoniumNinthetotalsoilNwiththebalancedapplicationofN,andalsomaintainedhigherricegrainyieldsandnitrogenuptake.GrainyieldwaspositivelycorrelatedwithtotalNuptake(r=0.875**),hydrolysableN(r=0.608**),hydrolysableammoniumN(r=0.560**)andthehydrolysableunknownN(r=0.417**).TotalNuptakewaspositivelycorrelatedwithhydrolysableN(r=0.608**),hydrolysableammoniumN(r=0.440**)andhydrolysableunknownN(r=0.431**).Soilnutrientdepletionand/orunbalancedfertilizationtoricecropreducedNcontentinsoilmicrobialbiomass,andthereforeincreasedC/Nratio,suggestinganegativeeffectonthetotalmicrobialbiomassinthesoil.

简介：Soilsalinityandalkalinityadverselyaffectstheproductivityandgrainqualityofrice.Thegrainqualityof19ricegenotypescharacterizedassalttolerant(T),semi-tolerant(ST)andsensitive(S)wasassessedinlysimeterscontainingsalineandhighlyalkalinesoils.Headricerecoverywasreducedbysalinitystresswhereasitwasnotaffectedbyalkalinitystress.Theratiooflengthtowidth(graindimensions)wassignificantlyreducedintheTgenotypeevenatlowelectricalconductivity(EC,4mS/cm)andalkalinity(pH9.5),whereasintheSTgenotype,itwassignificantlyreducedathighsalinity(EC8mS/cm).TherewasnosignificanteffectofanylevelsofsalinityoralkalinityongraindimensionsintheSgenotype.AmylosecontentwassignificantlyreducedinTandSTgroupsevenatlowEC(4mS/cm)andalkalinity(pH9.5)andtheeffectintheSgenotypewasonlyathighsalinity.Starchcontentshowedsignificantreductionathighsalinityandalkalinity(EC8mS/cmandpH9.8)intheTandSTgenotypesandnosignificanteffectwasobservedintheSgenotype.Theeffectofbothlevelsofsalinity(EC4and8mS/cm)andhighalkalinity(pH9.8)ongelconsistencywasobservedonlyintheSgenotype.ThetolerantgenotypesIR36underhighsalinity,andCSR10andCSR11underalkalistressshowedlessreductioninamylosecontent.TheTgenotypeBR4-10,andSTgenotypesCSR30,CSR29andCSR13showedbettergelconsistencyundersalineandalkalistress.Amylosecontentwasaffectedevenatlowsalinitystressandthusimportanttobeconsideredinbreedingriceforsalttolerance.Overall,thegrainqualityofTandSTgenotypeswaslessaffectedbysalineandalkalistresscomparedtoSones.

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简介：Inthispaper,withK+,Ca2+andFe3+astheobjectsofstudy,retardationofsoil–bentonite(SB)barriermaterialsformetalionswithdifferentvalencesisinvestigated,andtheadsorptionmechanism,migrationpatternsandpermeationbehaviorareexploredsoastoprovideatheoreticalbasisfortheirapplication.TheresultsshowthattheadsorptionprocessformetalionswithdifferentvalencesbySBbarriermaterialsisfast,andthehigherthevalence,thegreatertheadsorptioncapacity.Thefttingoftheadsorptionprocessconformstopseudo-second-orderadsorptionkineticsandLangmuir–Freundlichadsorptionequation,whichexplainsthatchemicaladsorptionisthedominatingstateandthattheSBsurfacehascertainheterogeneity.ThepermeabilitycoeffcientofK+,Ca2+andFe3+inSBeachhasamaximumandthehigherthevalence,thesoonerthemaximumappears.Alsothehigherthevalence,themoreobvioustheeffectonSBretardationperformance;andthesoonertheionbreaksthroughthebarrierwallcompletely,thatis,thewall’sretardationperformanceforhighervalentionsmaydecline.

简介：土壤结构接口的行为在土壤结构相互作用的定义起一个主要作用。在这糊双性人潜力表面为土壤结构接口的elasto塑料的模型被建议以便描述接口变丑行为，包括紧张弄软和正常膨胀性。模型在概括潜在的理论，土壤结构接口问题作为压力地里的一个二维的数学问题在是问候的框架被提出，并且塑料州的方程被用来代替传统的域表面。关系曲线砍应力和正切的紧张被明智的功能由夸张功能和夸张正割功能填写了的一片适合，当关系正常弯时，紧张和正切的紧张被明智的功能由二次的功能和夸张正割功能填写了的另一片适合。建议的途径有的优点导出elastoplastic没有要求的组成的矩阵塑料潜在的功能和收益表面。而且，数学原则是清楚的，并且全部模型参数能被试验性的测试识别。最后，模型的预言与获得从的试验性的结果相比简单砍在正常压力下面的测试，和结果证明模型讲理、实际。

简介：Aschemeisdevelopedforanalysingtheinteractionbetweenafoundationandanonlin-earrockandsoilmedium,inwhichthefoundationisconsideredasalinearelasticbodyandatypicalboundaryintegralequationmethod(BIEM)isemployed.(hathebasisoftakingthenonlinearproper-tiesofthemediumintoaccount,aperturbationBIEMisdeveloped.Thefundamentalequationsforthenonlinearcouplinganalysisareformulated,andtypicalproblemsaresolvedanddiscussedbythepre-sentmethod.

简介：很多个基于过程的模型为确定被开发了在agro生态系统的碳(C)隐遁。DeNitrification分解(DNDC)模型被用来模仿并且确定长期(1980–2008)玷污器官的碳(SOC)在重要的生产大米的省的动力学，江苏，中国。在SOC存储的变化从在空间分辨率不同的二个土壤数据库被估计：由68个多角形和土壤组成的一个县数据库为在江苏的稻田的所有3.7Mha的701个多角形的基于补丁的数据库。分别地，当那与好决定估计数据库是201.6和216.2时，有粗糙的决定县数据库的模仿的SOC存储在2008在1980和170.3–305.1TgC在131.0–320.6TgC之间变化了在1980和2008的TgC分别地。建模，土壤数据库在空间分辨率不同的结果显示用土壤输入，有更高的分辨率的数据实质地增加了建模的结果的精确性；并且当缺乏详细土壤数据集时，DNDC模型，有最敏感的因素(MSF)的parameterized应付属性无常的方法，尽管，能仍然生产可接受的结果与为在这份报纸报导的案例研究的多达60%的偏差。

简介：Thepaperinvestigatestheabilitytoretrievethetruesoilmoistureprofilebyassimilatingnear-surfacesoilmoistureintoasoilmoisturemodelwithanensembleKalmanfilter(EnKF)assimilationscheme,includingtheeffectofensemblesize,updateintervalandnonlinearitiesintheprofileretrieval,therequiredtimeforfullretrievalofthesoilmoistureprofiles,andthepossibleinfluenceofthedepthofthesoilmoistureobservation.Thesequestionsareaddressedbyadesktopstudyusingsyntheticdata.The'true'soilmoistureprofilesaregeneratedfromthesoilmoisturemodelundertheboundaryconditionof0.5cmd-1evaporation.Totesttheassimilationschemes,themodelisinitializedwithapoorinitialguessofthesoilmoistureprofile,anddifferentensemblesizesaretestedshowingthatanensembleof40membersisenoughtorepresentthecovarianceofthemodelforecasts.Alsocomparedaretheresultswiththosefromthedirectinsertionassimilationscheme,showingthattheEnKFissuperiortothedirectinsertionassimilationscheme,forhourlyobservations,withretrievalofthesoilmoistureprofilebeingachievedin16hascomparedto12daysormore.Fordailyobservations,thetruesoilmoistureprofileisachievedinabout15dayswiththeEnKF,butitisimpossibletoapproximatethetruemoisturewithin18daysbyusingdirectinsertion.ItisalsofoundthatobservationdepthdoesnothaveasignificanteffectonprofileretrievaltimefortheEnKF.Thenonlinearitieshavesomenegativeinfluenceontheoptimalestimatesofsoilmoistureprofilebutnotveryseriously.

简介：Apotexperimentwasconductedtostudytheeffectofnitrogenfertilizeronnitrogenandpotassiumuptakebyfourricecultivars.Resultsshowedthatthequadraticparabolarelationshipbetweenbiomassofriceandnitrogenlevelswasobserved,withthemaximumbiomassatthenitrogenlevelof150mgkg^-1.TherateofnitrogenandpotassiumuptakebythefourricecultivarsdependedongrowthstageandricecultivarwiththemaximumrateofNinShanyou-63andmaximumrateofKinKaiyou-5(hybridrice),respectively,Thekineticsofnitrogenandpotasssiumuptakebyriceplantcouldbequantitativelydescribedbythefollowingequations:y=a+blogt,y=ab+t^1/2andy=ae^-bt,Thebvalueintheequationswascorrelatedsignificantlytotheratesofnitrogenandpotassiumuptake(-↑NRand-↑KR,r=0.901^**-0.990^**),suggestingthatthebvaluecouldbeusedtodistinguishtheindexofnitrogenandpotassiumuptakecapacityofrice.Themaximumvaluesofnitrogenuptakebyplant(bvalue)andapparentrecoveryoffertilizernitrogenwereobservedinShanyou-63,andtheminimumvalueinEryou-6078,However,thecapacityofpotassiumuptake(bvalue)bykaiyou-5rankedfirstandthatbyShanyou-63second.Therewasasignificantlinearrelationshipbetweennitrogenlevelandnitrogenuptakebyrice,butaquadraticparabolarelationshipwasfoundbetweennitrogenlevelandpatassiumuptakebyrice.Theapplicationofnitrogenfertilzierdecreasedtheratiosofpotassiumtonitrogenuptakebyriceplant.Thegreatestreductionintheratiowasobservedathihtnitrogenlevel,andtheleastreductionwasfouninKaiyou-5andShanyou-63duetotheirgreaterabilitytoabsorbpotassium.

简介：中国经历了使用在最近的十年改变的戏剧的土地，与显著环境、社会经济的后果。Hengshan县，在西北中国的风神黄土的区域定位了，被调查为环境、长期的农村经济开发说明陆地使用变化和他们的含意。在Hengshan县的农田显著地减少了在期间19902003，而森林土地和草地增加了。土地在不同时期之中显著地改变了的农田，果园陆地，森林陆地和建设的变换率：19901995，19952000和20002003。果园土地，草地和构造土地的变换是主导的在19901995，而到森林土地的农田的变换主要发生了在20002003。结果在机构的政策和陆地管理的政治经济建议了深刻转变，包括综合土壤侵蚀控制工程，面向市场的经济的采纳和‘Grain-for-Green'政策的实现，在在中国的这个时期期间。为了完成长期的持续土地，在Hengshan使用县，努力应该瞄准象建立节俭陆地的机制支持陆地生产率一样增加农村家庭的离开农场收入，除了保存措施。

简介：Microbialcommunityfunctionaldiversityisasensitiveindicatorofsoil.Forestfirescanchangemicrobialcommunityfunctionaldiversity.Inthisresearch,thefiredsoilsampleswerecollectedfromHuzhongofDaxing’anlinginHeilongjiangProvince.ThefunctionaldiversityofsoilmicrobialcommunitywasdetectedbyBIOLOGsystem.Theaveragewellcolordevelopment(AWCD)inBIOLOGplatesindicatedtheabilityofcarbonsubstrateutilizationofmicrobialcommunity.TheindicesofShannon,SimpsonandMcintoshwerecalculatedtoshowtherichness,dominanceandevennessofthefunctionaldiversity,andtheprincipalcomponentanalysisofsubstratereactionsreflectedthemaincarbonsourcesutilizedbymicrobialcommunity.TheresultsshowedthatallthesamplesexhibitedthereductionofAWCDduringthefirst144hoursofincubation,buttherewereobviousdifferencesinthereductiondegreeamongthesamples.Allkindsoffireintensitiescouldinfluencemicrobialcommunityfunctionaldiversity.Thelowfireintensityincreasedtherichness(Shannon),dominance(Simpson)andevenness(Mcintosh)ofmicrobialcommunity.However,theintermediateandhighfireintensityreducedtheseparameters,suggestingthattheburnedsoilemittedgaseousnitrogen,anumberoforganiccarbonandavailablephosphorus,whichcausedthereductionofthemicroorganisminquantityandtype,andchangeinsoilingredients.Theorganicmaterialreducedintheburnedsoil,inthesametime,thepHvaluesrose,whichchangedenvironmentinwhichmicroorganismlives.Thechangedenvironmentmightnotbeconducivetoactivitiesofthemicroorganism.Theprincipalcomponentanalysisshowedthatthemaincarbonsourcesforsoilmicrobeswerecarbohydratesandaminoacidsandthecarbonsubstrateutilizationpatternsindifferentsamplesweresignificantdifferent.Theresultsindicatedthatfunctionaldiversityofsoilmicrobeswerealteredbyforestfires,andtheabilityofmicrobestoutilizecarbonsourceandthetypeofcarbonsourceswereaffectedbydif

简介：ThecurrentresearchfocusesonsoilparticleseparateandtotalorganiccarbonandnitrogeninQuercusaquifolioidesforestinBalangshan,WolongNaturalReserve,Sichuan,andtheircorrelationattreealtitudinalgradient.Theresultshowsthat:ThesoilparticleseparateofQ.quifolioidesforestismainlyofsilts,andthesoiltextureismediumtexturedsoils;Thecontentsofsoiltotalorganiccarboncontentandnitrogencontentin0-15cmlayerarehigherthanthatin15-30cmlayerindifferentattitudegradients;thetotalorganiccarboncontentinthetopsoilshowsalow-high-lowtendencyatdifferentaltitudinalgradients,whereasthatofthesubsoilshowsagrowingtendency;TheC/NratioofQ.aquifolioidesforestisrelativelysmall,withanaverageof12.77;Thecorrelationanalysisbetweenthesoiltotalorganiccarbonandnitrogencontentandsoilparticleseparaterespectivelytellsus:contentsofsoilorganiccarbonisverysignificantlypositivelycorrelatedwithtotalnitrogeninthetwosoillayers(P<0.01)at3549m,nocorrelationat2551m;thecontentsoftotalorganiccarbonandnitrogenareverysignificantlypositivelyrespectiverespectivelywithcoarsesiltcontentin0-15cmand15-30cmsoillayers(P<0.05),butnegativelywithclayindifferentlayers(P<0.05)in0-15cmsoillayerat3549m,significantlypositively(P<0.05)andverysignificantlypositivelycorrelated(P<0.01)respectivelywithcoarsesiltcontentindifferentsoillayersat3091m,verysignificantlyandsignificantlypositivelycorrelatedrespectivelywithfinesandcontentindifferentsoillayersat2551m,butnegativelywithfinesiltcontentin15-30cmsoillayer.Finally,inthispapertheresultspresentedthatrelationshipsamongsoilparticleseparateandtotalorganiccarbonandnitrogencontentarequitecomplicationsinQ.aquifolioidesforestatdifferentaltitudinalgradient.

简介：从地下的管子的漏能导致被破坏并且引起损坏到邻近的基础结构的基础。包围漏的区域的土壤粒子能从由漏的液体的土壤矩阵被动员，代替，并且甚至洗了，产生虚空或洞。用acoupled的二维的模拟分离元素方法和格子Boltzmann方法(DEMLBM)被用来调查一个土壤床题目的行为到局部地注射的液体，它在一根管子中代表一条漏缝。内部粒子的表面精力的各种各样的价值也被采用为连贯的粒子的机械效果建模。结果建议内部粒子的表面精力极大地关于漏的液体影响床反应，包括开始洞，洞形状和它的进化率的过量压力。

简介：为掌握某型自行火炮在几种典型软土地面上的行驶与射击动态响应规律,探索前轮车辙对后轮的影响,基于多体系统动力学软件ADAMS和有限元软件ABAQUS,建立自行火炮刚柔耦合行驶与射击动力学模型。使用soft-soil轮胎模型,考虑各种土壤的弹塑性、承压特性、剪切特性和轮胎变形等因素,全面分析火炮行驶与行进间射击关键位置的动态响应,得到相比于不考虑前后轮车辙影响的区别和特点。获得更加真实的考虑了地面环境的结论,进一步为作战地面参数化构建技术以及车辆振动干扰研究等提供参考依据。

简介：Duetothewideapplicationsofarchesinundergroundprotectivestructures,dynamicanalysisofcircu-lararchesincludingsoil-structureinteractionsisimportant.Inthispaper,anexactsolutionoftheforcedvibrationofcirculararchessubjectedtosubsurfacedenotationforcesisobtained.Thedynamicsoil-structureinteractionisconsideredwiththeintroductionofaninterfacialdampingbetweenthestructureelementandthesurroundingsoilintotheequationofmotion.Byneglectingtheinfluencesofshear,rotaryinertiaandtangentialforcesandassumingthearchincompressible,theequationsofmotionoftheburiedarchesweresetup.Analyticalsolutionsofthedynamicresponsesoftheprotectivearcheswerededucedbymeansofmodalsuperposition.Archeswithdifferentopeningangles,acousticimpedancesandrise-spanratioswereanalyzedtodiscusstheirinfluencesonanarch.Thetheoreticalanalysissuggestsblastloadsforelasticdesignsandpredictsthepotentialfailuremodesforburiedprotectivearches.