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.

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：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：植物侵略可以改变碳(C)和氮(N)周期，而是方向，如此的改变的大小很少被确定了，这长被认出了。在这研究，我们确定了效果由有害异国情调的植物的侵略引起了，Kalanchoedaigremontiana(Crassulaceae)，在在在委内瑞拉的一个半干旱的地区的土壤的C和N矿化作用和酶、微生物引起的活动上。我们比较了与这些进程(脱氢酶，-glucosidase,glucosaminidase，和urease的C和N矿化作用时间和累积的值，荧光黄diacetatehydrolytic活动，和活动)在之间联系的土壤参数入侵并且邻近的非入侵的地点。另外，在这些参数之中的关联和物理化学药品的性质也是的土壤检验了决定积极反馈是否在滋养的可获得性和K之间存在。daigremontiana侵略。总的来说，我们的结果证明到NH4+的有机化合物的那个C矿化作用和转变在K开拓殖民地于的地点被赞成。daigremontiana。与这种，我们发现了NH4+-N和C和最低矿化作用时间的最高累积的数量。这些结果能被urease和glucosaminidase的更高的活动在K的影响下面在土壤解释。daigremontiana。另外，有机物和潮湿的更高的数量在入侵的土壤力量帮助C和N矿化作用满足。在结论，由K的新热带区的半干旱的地区的侵略。daigremontiana可以影响这种盖住的土壤的化学、生物的性质，增加滋养的bioavailability，及时，它能便于侵略过程。

简介：印射土壤硝酸盐氮(NO3-N)的空间分发是重要的指导氮申请以及估计沥滤进地下水的NO3-N的环境风险。我们采用了univariate和混合geostatistical方法在东北佛罗里达越过一处风景印射土壤NO3-N的空间分发。土壤样品从四深度增长被收集(030，3060，60120和120180厘米)基于土壤，土地使用和举起阶层从用成层的随机识别并且嵌套采样的147个采样地点设计。在二层是的顶的土壤NO3-N分布空间地，汽车相关并且印射使用木头正常kriging。为NO3-N预言的环境关联模型用线性、非线性的回归方法被导出，并且采用了开发NO3-N趋势地图。陆地使用和它从卫星形象导出的相关变量作为重要变量被识别用环境关联模型预言NO3-N。当木头正常kriging生产了顺利变化的地图时，从环境关联模型导出的趋势地图产生了空间地异构的地图。趋势地图与趋势模型剩余的平常的kriging预言被相结合开发回归kriging预言地图，它给了最好的NO3-N预言。因为土地使用和遥远地察觉到的数据是容易地可得到的并且有大部分，与地相比的更好的空间分辨率取样了土壤，我们的调查结果基于为风景的使用和遥远地察觉到的数据放大土壤NO3-N印射的土地建议了环境关联模型的功效。实现的方法论为在另外的风景土壤NO3-N印射是可转让的。

简介：在中国的三个峡区域，土壤侵蚀和结果的非点来源污染和生态的降级危及了农业生态系统和新鲜的水水库。尽管努力被承担了从斜坡土地减少土壤和水损失，为柠檬生产使用，管理的效果的信息在土壤富饶索引上练习也有限或不存在。这研究被进行比较10年各种各样的管理惯例的效果，柠檬与白苜蓿(WC)杂种，有稻草(SM)的柠檬mulched，柠檬与轮廓灌木篱墙(CH)杂种，有透不过的膜(IM)的柠檬果园土地，并且柠檬与小麦(Triticumaestivum)和花生(Arachrishypogaea)(WP)杂种，，土壤富饶上的处理与常规柠檬管理(厘米)的索引。结果证明器官的碳，全部、可得到的氮，可得到的钾，和水马厩聚集的土壤(>0.25公里)在0–5厘米深度的内容比CM处理为WC和SM处理是更高的。也在沿着WC和SM治疗的斜坡的土壤生育力有空间变化。土壤总数和可得到的氮，磷，和钾，和水马厩聚集(>0.25公里)在两个满足0–5和5–20厘米深度比CM处理为CH和IM处理是更高的。氮和可得到的钾满足的可得到的平均土壤比CM处理为WP处理是更高的，但是WP处理在器官的碳，全部的氮，和水马厩聚集的土壤上有小效果(>0.25公里)内容。这些建议白苜蓿杂种和稻草mulching是最有效的途径在三个峡区域的柠檬果园土地改进土壤富饶。

简介：因为它的高收益潜力，到边缘的地点的改编，和忍耐，Switchgrass(PanicumvirgatumL.)作为持续bioenergy庄稼被建议了到水和滋养的限制。生物资源精力庄稼生产的潜在的效果的更好的理解在土壤上练习生物性质，有机物动力学对它的生产批评。我们的目的在学院车站，达拉斯，和Stephenville是与成长得典型地的庄稼相比在不同土壤在温暖季节的长期的switchgrass下面在C水池评估变化镇定的，在2001年2月的TX。采样深度是05，515，和1530厘米。Switchgrass增加了土壤器官的C(SOC)，玷污微生物引起的生物资源C(SMBC)，mineralizableC，和与常规收割相比的微粒有机物C(POM-C)系统。土壤C集中在顺序：长期的沿海的bermudagrass[Cynodondactylon(L.)Pers.]switchgrass1997>常规收割系统。土壤C集中趋于与增加泥土内容增加。更大的微生物引起的生物资源C跟随了达拉斯的顺序>学院车站>Stephenville，并且在达拉斯在Stephenville从约180mgCkg1土壤到1900mgCkg1土壤。微粒器官的C比对管理的另外的部分更敏感，像在与常规收割系统相比的长期的沿海的bermudagrass下面的6褶层一样增加。我们的学习显示进switchgrass生产的常规收割系统的变换能扣押更多的SOC并且改进土壤在南部的美国的生物性质。

简介：低氮(N)可获得性经常导致桉树类种植园的减少的生产率。我们学习了四桉树类种植园的反应(E的二种植园。沿海的低地上的tereticornis，和E的二种植园。宏大在西方的Ghats的高地区域，Kerala，印度)到N增加并且象N可获得性的另外的索引一样联系了这回答到季节的N矿化作用，为了检验土壤的用途，为预言桉树类生长的反应到增加的N化肥基于N矿化作用的指示物。几生物化学的指示物被检验让他们的能力预言反应到N化肥，包括全部的土壤N，土壤C:在厌氧、氧气的孵化期间释放的N比率，和N。结果证明氮化肥增加从7%～70%越过4个地点增加了生产率，在氧气的孵化期间释放的N越过4个地点(R2=0.92,p<0.01)与化肥反应有最高的关联，并且那建模的季节的土壤Nmineralisation比在氧气的孵化期间释放的N是化肥反应的一个更差的预言者。虽然一些这些指示物是有希望的，他们需要更宽的确认并且在他们能是以前，测试习惯性地适用。

简介：Wetlandsoilqualitydegradationcausedbylarge-scaleagriculturalreclamationontheSanjiangPlainofNortheastChinahasbeenwidelyreported.Arelativesoilqualityevaluation(RSQE)modelandaprojectionpursuitevaluation(PPE)modelbasedonreal-codedacceleratinggeneticalgorithmwereintroducedtoevaluatequalityvariationsintoplayersofthemainwetlandsoilsontheSanjiangPlainin1999and2003,respectively.Assoilqualitydegradationboundarieswerevague,thisstudyestablishedtwofuzzysyntheticevaluation(FSE)modelsbasedontheoriginaldataandcriteriausedintheRSQEandPPEmodels.TheoutputsofthetwoFSEmodelswereobtainedbychoosingtwofuzzycompositeoperatorsM(∧,∨)andM(·,⊕).StatisticalanalysisshowedthattheresultsoftheFSE,RSQE,andPPEmodelswerecorrelated.Inparticular,outputsoftheFSEmodelusingM(·,⊕)weresignificantlycorrelatedwiththoseoftheRSQEmodelwithr=0.989atP<0.01.ComparedwithRSQEandPPEmodels,theFSEmodelmaybemoreobjectiveinshowingsoilqualityvariationsandwasclosertothenaturalsituation,showingthefeasibilityandapplicabilityoftheFSEmodelinevaluatingsoilqualitydegradation.However,thechoiceofcompositeoperatorwasofcriticalimportance.ThestudyofwetlandsoilqualitydegradationontheSanjiangPlainwasofscientificandpracticalsignificanceforprotectionandmanagementofsoilsandforsustainabledevelopmentofagricultureinthisareainthefuture.

简介：Themajorityofrice(OryzasativaL.)producedinthesouthernUSAisdrill-seededandgrownunderupland-likeconditionsbecausepermanentfloodingisestablishedafterthefour-leafstage.Therefore,riceduringtheseedlinggrowthstagewillbesubjectedtovariablesoilmoisturecontent.Agreenhouseexperimentwasconductedtoevaluatetheperformanceof15ricecultivarscommonlygrowninMississippiofUSAunderearly-seasonsoilmoisturestress.Twentymorpho-physiologicalparametersofriceseedlingssubjectedtothreedifferentlevels(100%,66%and33%fieldcapacity)ofsoilmoisture,from10to30daftersowing,weremeasured.Significantmoisturestress×treatmentinteraction(P<0.001)wasobservedformostoftheparameters.Further,thetotaldroughtresponseindex(TDRI)wasdevelopedtoscorethecultivarsfordroughttolerancewiththevariationfrom26.88to36.21.Accordingly,thecultivarswereclassifiedintodifferentgroupsoftolerance.ThecultivarsCL152andCL142-ARwereclassifiedastheleastandthemosttoleranttodroughtbasedonTDRIandstandarddeviation,respectively.Eventhoughbothtotalroot(R2=0.98)orshoot(R2=0.76)droughtresponsesindiceswerepositivelycorrelatedwithTDRI,roottraitswereimportantinderivingtheindices.Therefore,TDRIcouldbeusedtoselectcultivarsfordroughttoleranceinagivenenvironmentanddevelopricevarietieswithearly-seasondroughttolerance.However,furtherresearchisneededtoidentifyandcharacterizetoleranceatotherstagestoassistbreedingprogramsinrice.

简介：narG基因经常为细菌的减少硝酸盐的社区分析被用作一个分子的标记。在这研究，指向narG基因的教材的一个新集合被设计并且把使中毒反应的坡度胶化电气泳动(PCR-DGGE)试金用于嵌套半的聚合酶链。新教材的潜力在直接从在中央、南部的意大利散布的五个不同试验性的地点从土壤提取的DNA上被验证。教材的特性被切除决定，扩大，并且乐队定序由DGGE解决了。种系发生的分析显示出在从学习的土壤检索的序列和narG序列之间的关联从并且-Proteobacteria。这些教材扩展了存在为在土壤的减少硝酸盐的细菌的社区的尺寸和差异上的生态的学习的分子的工具。

简介：Thecharacteristicsofarbuscularmycorrhizalfungal(AMF)communitystructureinvarioussoildepthsandgrowingseasonsofwatermelon(Citrullusvulgaris)grownincommercialgreenhousesinDaxingofBeijingandWeifangandLaiyangofShandong,Chinawereinvestigatedusingbothmorphologicalidentificationanddenaturinggradientgelelectrophoresis.Thesampledsoilshadbeenusedforcontinuousgreenhouseproductionofwatermelonfor0,5,10,15,or20years.Glomusclaroideumwasthedominantspeciesinthegreenhousesoilsplantedfor5,10,and15yearsinLaiyang,whileGlomusmosseaeandGlomusetunicatumweredominantinthenearbyopenfarmlandsoil.Sorenson'ssimilarityindexofAMFcommunitycompositionrangedfrom0.67to0.84inthesoilsplantedfor5years,andfrom0.29to0.33for20yearsamongthethreelocations.Sporeabundance,speciesrichness,andtheShannonindexwerehighestnearthesoilsurface(0-10cm)anddecreasedwithsoildepth,andhigherinJuneandOctoberthaninAugustandDecember.CanonicalcorrespondenceanalysisshowedthatavailablePandthenumberofyearsthatsoilhadbeenusedforgreenhouseproductionwerethemainfactorscontributingtothevarianceofAMFcommunitycomposition.ItwasconcludedthatthecommunitystructureofAMFwasmainlyinfluencedbysoilavailablePandplantingtimeofwatermelonaswellasbysoildepthandseasonalvariationinthecommercialgreenhouse.

简介：土壤温度是土壤上的一个主要有效因素并且种生物性质。灌溉能影响土壤温度并且从而在植物生长上导致温度效果，它可以由于更高的产量和植物营养导致经济增加。一个地实验被执行包括完整的灌溉(FI)调查三灌溉策略的效果，弄干的部分根地区(PRD)和土壤温度上的赤字灌溉(DI)和谷物上的作为结果的结果让步并且玉米(泽·梅L.)的N举起。土壤温度被时间领域反射计(TDR)测量传感器在2010成长季节期间。灌溉处理在种以后从55～107d被使用。PRD处理引起了土壤温度在为一个更长的时期的一个有利领域(为超过60%测量日期)作为到更深的土壤层的水运动的作为结果的结果与另外的处理相比；PRD处理也在更深的土壤深度把土壤温度归结为在为玉米根生长的最大的有利土壤温度下面，它由于水可获得性和有利土壤温度导致了更深的根穿入。比作FI治疗，PRD治疗增加了根水举起50%并且当这没在植物生长上由于DI的否定温度效果部分在DI治疗被观察时，没在全部的N举起引起重要减小，它因而影响了水和滋养的举起。在PRD处理的一个更长的植被时期在FI处理由于更高的叶N集中被观察，在玉米谷物产量的重要减小都没发生在PRD处理，与那些相比。在结果上基于，让15.2%流水在完整的成长季节期间节省，PRD灌溉将断然影响是的土壤温度和水和滋养的举起一作为结果，它将从而在玉米谷物产量阻止重要减小。

简介：Prescribedfireisacommoneconomicalandeffectiveforestrypractice,andthereforeitisimportanttounderstandtheeffectsoffireonsoilpropertiesforbettersoilmanagement.Weinvestigatedtheimpactsoflow-intensityprescribedfireonthemicrobialandchemicalpropertiesofthetopsoilinaHungarianoak(QuercusfrainettoTen.)forest.Theresearchfocusedonmicrobialsoilparameters(microbialsoilrespiration(RSM),soilmicrobialbiomasscarbon(Cmic)andmetabolicquotient(qCO2)andchemicaltopsoilproperties(soilacidity(pH),electricalconductivity(EC),carbon(C),nitrogen(N),C/Nratioandexchangeablecations).Meanannualcomparisonsshowsignificantdifferencesinfourparameters(C/Nratio,soilpH,CmicandqCO2)whilemonthlycomparisonsdonotrevealanysignificantdifferences.SoilpHincreasedslightlyintheburnedplotsandhadasignificantlypositivecorrelationwithexchangeablecationsMg,Ca,MnandK.ThemeanannualC/Nratiowassignificantlyhigherintheburnedplots(28.5:1)thaninthecontrolplots(27.0:1).ThemeanannualCmic(0.6mgg-1)wassignificantlyloweralthoughqCO2(2.5lgCO2–CmgCmich-1)wassignificantlyhigher,likelyresultingfromthemicrobialresponsetofire-inducedenvironmentalstress.Low-intensityprescribedfirecausedveryshort-livedchanges.TheannualmeanvaluesofC/Nratio,pH,CmicandqCO2showedsignificantdifferences.

简介：Dustemissionsfromsmelters,asamajorcontributortoheavymetalcontaminationinsoils,couldseverelyinfluencesoilquality.Downwindsurfacesoilswithin1.5kmofazincsmelter,whichwasactivefor10yearsbutceasedin2000,inMaguTown,GuizhouProvince,ChinawereselectedtoexaminePb,Zn,andCdconcentrationsandtheirfractionationalongadistancegradientfromazincsmelter,andtostudythepossiblee?ectsofPb,Zn,andCdaccumulationonsoilmicroorganismsbycomparingwithareferencesoillocatedatadownwinddistanceof10kmfromthezincsmelter.Soilswithin1.5kmofthezincsmelteraccumulatedhighlevelsofheavymetalsZn(508mgkg-1),Pb(95.6mgkg-1),andCd(5.98mgkg-1)withlowratiosofZn/Cd(59.1-115)andPb/Cd(12.4-23.4).Compositepollutionindices(CPIs)ofsurfacesoils(2.52-15.2)were3to13timeshigherthanthereferencesoils.Inmetalaccumulatedsoils,exchangeablepluscarbonate-boundfractionsaccountedformorethan10%ofthetotalZn,Pb,andCd.Thesaturationdegreeofmetals(SDM)insoilswithin1.5kmofthesmelter(averaging1.25)wassixtimeshigherthanthatofthereferencesoils(0.209).Asmallersoilmicrobialbiomasswasfoundmorefrequentlyinmetalaccumulatedsoils(85.1-438μgCg-1)thaninreferencesoils(497μgCg-1),andanegativecorrelation(P<0.01)ofsoilmicrobialbiomasscarbontoorganiccarbonratio(Cmic/Corg)withSDMwasobserved.Microbialconsumptionofcarbonsourceswasmorerapidincontaminatedsoilsthaninreferencesoils,andashiftinthesubstrateutilizationpatternwasapparentandwasnegativelycorrelatedwithSDM(R=-0.773,P<0.01).Consequently,dustdepositedPb,Zn,andCdinsoilsfromzincsmeltingwerereadilymobilized,andweredetrimentaltosoilqualitymainlyinrespectofmicrobialbiomass.

简介：bispyribac钠10%SC和butachlor的效果土壤上的50%SC在移植秋收作物米饭的物理化学的性质和microflora在二个季节(2010和2011)被调查。体积密度，水成立能力，潮湿内容，土壤pH，有机物内容，电的传导性，以及全部的氮，可得到的磷和可得到的钾内容上的除草剂的效果与microflora人口(全部的细菌，放射菌类和真菌)一起被分析。在土壤的没有重要变化物理化学的性质被观察。除草剂处理开始在微生物引起的计数导致了减少。与在一可观的时间以内的应用除草剂的降级，microflora人口甚至在除草剂的申请以后在60d超过了起始的计数。

简介：Fieldexperimentswereconductedinamaize(ZeamaysL.)fieldofacalcareousfluvo-aquicsoilinNorthChinaPlainforstudyingthefateandammonialossofurea-Nappliedatseedlingstage,aswellastheeffectivenessofcoatedcalciumcarbide(CCC)inreducingNlossandinimprovingtheyieldefficiencyofurea.Resultsshowthat:(1)Forthesurface-broadcasttreatmentammoniavolatilization(measuredwithmicro-meteorologicaltechnique)tookplacequickly,reachedthepeak20-26hrafterapplication,andthendeclinedgradually;thecumulativeammonialossapproachedthemaximum188hrafterapplication(30%oftheNapplied),andincreasedonlyto32%284hrafterapplication;thelatteraccountedfor71%ofthetotalloss(45%ofappliedN).(2)Inthecaseofpointplacementatadepthof5-10cm,ammonialoss188hrafterapplicationwasonly12%oftheNapplied,accountingfor40%ofthetotalloss.(3)Therewasnodifferenceintotallossbetweentheapplicationdepthsof6cmand10cm,thelossofthemwas30%and29%,respectively.(4)TotallossofNappliedatlowerrate(40kgN/ha)withpointdeepplacementat6cmdepthwasfoundonly4%oftheNapplied,itroseupto30%whentherateofapplicationincreasedto80kgN/ha.(5)Thenitrificationinhibitor,CCC,seemedtoenhanceNlossofurearatherthanreduceit,anddidnotshowanybenefiteffectinimprovingtheyieldefficiencyofurea,whichispresumablyduetothehighpotentialofammoniavolatilizationinthesoilandclimaticconditionsunderinvestigation.