简介:为深入了解(PAM)与肥料混施的作用和效果,确定农业应用技术参数,通过室内土柱模拟试验,分析PAM与尿素混施对土壤蒸发特性的影响。结果表明:1)0~10cm浅层混施,在PAM用量0、0.05%和0.1%水平下,12d内尿素4个处理水平(尿素中纯氮占干土的质量比0、0.1%、0.2%、0.4%)对蒸发的影响无差异,12d后,差异开始逐渐凸显,总体呈现随着尿素施用量的增加蒸发量减小的规律;在同一尿素水平下,累积蒸发量随着PAM用量的增加而减小;2)10~20cm深层混施,在同一PAM水平下,尿素4个处理中,不施尿素对照处理累积蒸发量最大,在同一尿素水平下,累积蒸发量总体呈现随着PAM用量的增加而减小的趋势;3)深施各处理土壤总蒸发量普遍高于浅施各处理,0~10cm浅层混施,前5d日蒸发量迅速下降,5~25d日蒸发量波动性缓慢下降,25d后日蒸发量趋于稳定;10~20cm深层混施,前10d日蒸发量波动性保持近似水平,12d以后开始逐渐下降,25d以后又趋于稳定;4)PAM和尿素处理,都抑制了土壤的蒸发,相对于尿素,PAM对蒸发的抑制作用更强。
简介:Twopotexperimentswithacompletelyrandomdesignand4replicationswereperformedinagreenhousetoexaminetheresponsedifferenceof17cultivarsofpakchoi(BrassicachinensisL.)growninaCu-spikedandacleansoiltoCu.relativelytolerant.Whenthe17cultivarsofpakchoigrewincleangardensoil,theCuconcentrationsintheabovegroundpartwerepositivelycorrelated(r=0.6693)withtheirrootCuconcentrations.However,whentheygrewintheCu-spikedsoilahighlynegativecorrelationcoefficient(r=-0.5376)wasobtainedintheCuconcentrationbetweentheabovegroundpartandtheroot.ThismeantthattheCutolerantcultivarshadaweakabilitytotransferCufromtheirroottotheirabovegroundpart,andthereforestoredmuchmoreCuintheirrootthantheCusensitivecultivars.
简介:Apotexperimentwascarriedouttostudytheeffectsofthreearbuscularmycorrhizalfungi(AMF),includingGlomusintraradices,GlomusconstrictumandGlomusmosseae,onthegrowth,rootcolonizationandCdaccumulationofmarigold(TageteserectaL.)atCdadditionlevelsof0,5and50mgkg-1insoil.Thephysiologicalcharacteristics,suchaschlorophyllcontent,solublesugarcontent,solubleproteincontentandantioxidantenzymeactivity,ofTageteserectaL.werealsoinvestigated.ThesymbioticrelationshipbetweenthemarigoldplantandarbuscularmycorrhizalfungiwaswellestablishedunderCdstress.ThesymbioticrelationshipwasreffectedbythebetterphysiobiochemicalparametersofthemarigoldplantsinoculatedwiththethreeAMFisolateswherethecolonizationratesintherootswerebetween34.3%and88.8%.Comparedwiththenon-inoculatedmarigoldplants,theshootandrootbiomassoftheinoculatedmarigoldplantsincreasedby15.2%-47.5%and47.8%-130.1%,respectively,andtheCdconcentrationandaccumulationdecreased.ThechlorophyllandsolublesugarcontentsinthemycorrhizalmarigoldplantsincreasedwithCdaddition,indicatingthatAMFinoculationhelpedthemarigoldplantstogrowbyresistingCdstress.TheantioxidantenzymesreacteddifferentlywiththethreeAMFunderCdstress.ForplantsinoculatedwithG.constrictumandG.mosseae,theactivitiesofsuperoxidedismutase(SOD)andcatalase(CAT)increasedwithincreasingCdaddition,butperoxidase(POD)activitydecreasedwithincreasingCdaddition.ForplantsinoculatedwithG.intraradices,threeoftheantioxidantenzymeactivitiesweresignificantlydecreasedathighlevelsofCdaddition.Overall,theactivitiesofthethreeantioxidantenzymesintheplantsinoculatedwithAMFwerehigherthanthoseoftheplantswithoutAMFinoculationunderCdstress.Ourresultssupporttheviewthatantioxidantenzymeshaveagreatinfluenceonthebiomassofplants,andAMFcanimprovethecapabilityofreactiveoxygenspecie
简介:植物给供应任何一个NH+4或不的N消息提供者显示出不同生长回答?3。不同N来源的举起也影响根围pH并且因此土壤磷的简历可获得性,特别地在碱的土壤。在在水栽法并且在土壤文化种的燕麦(AvenanudaL.)的根围的植物生长,P举起,和P可获得性不与唯一的NH+4-N,脚底在供应下面被调查?3-N,或联合。脚底没有?3美联储燕麦植物比唯一的NH+4喂积累了更多的生物资源。当N与两NH+4-N被供应时,最高的生物资源累积被观察并且没有?3-N。植物根的生长与比例增加了没有?3in文化媒介。更好的根生长和更高的根/射击比率一致地被观察在没有?3美联储植物。然而,根活力是最高当N被供应没有时?3+NH+4。NH+4供应减少了根围pH但是没由在土壤种,CaHPO4作为P增加了的植物影响P举起来源。没有P缺乏被观察,并且植物P集中通常在2gkg上面?1。当N不部分或作为完全被供应时,P举起被增加?3-N,同样作为生物资源累积。结果建议那燕麦是一没有?3-preferring植物,并且没有?3-N为植物生长和根吸收能力的维护是必要的。有NH+4-N的N供应没改进P营养,它由于P缺乏的缺席是最可能的。