简介：Surfactantenhancedremediationisthoughttobeaneffectivemethodfortheremediationofsoilspollutedwithhydrophobicorganiccompounds.Desorptionofpolycyclicaromatichydrocarbons(PAHs)fromanabandonedmanufacturedgasplant(MGP)soilwasevaluatedusingfourelutingagentsincludingTritonX-100(TX100),sodiumdodecylbenzenesulfonate(SDBS),rhamnolipidwatersolution(RWS)andrhamnolipidfermentationbroth(RFB).TheweightsolubilizationratiosforacenaphtheneandfluorenewereintheorderofTX100>SDBS>RWS>RFB.TheSmvalue,whichindicatesthemaximumamountsofsurfactantsadsorbedinthesoil,wasintheorderofRWS>RFB>SDBS>TX100.Byusing8gL-1ofTX100,SDBSandRWSand100%ofRFB,theT-PAHsremovalfortheMGPsoilcontaminatedwith207.86mgT-PAHskg-1drysoilwas48.0%,45.7%,1.9%,and8.6%,respectively,whilethatdecreasedto41.6%,37%,0.38%,and1.3%forthesoilcontaminatedwith3494.78mgT-PAHskg-1drysoil.Only8gL-1TX100couldremovealltypesofthe16PAHspartlyintheMGPsoil,andtheremovalefficienciesofdifferentPAHsrangedfrom13%to77.8%.TheresultsofthisstudyhereinprovidevaluableinformationfortheselectionofTX100surfactantforremediatingPAH-contaminatedsoilsinMGP.

简介：Effectofdifferentshadinglevels(no-shading,80%shading,and40%shading)onphotosyntheticandstomatalresponsesincottonleaveswereinvestigatedunderconditionsofdifferentsoilwatercontentsinsummermidday.Allcottonleavesexhibitedsimilarbasicresponsestoshading,includingdecreasednetphotosyntheticrates,atendencytodecreaseintranspirationrates,andincreasedstomatalconductanceandintercellularCO2concentration.Theleafconductanceof80%shadedand40%shadedplantsincreasedby28%and16.7%comparedwithno-shadedplantsathighwater,respectively,butthenetphotosyntheticratesof80%shadedand40%shadedplantsdeclinedby50%and14.73%,respectively,Resultsshowedthatcombinedeffectofsoilmoistureandshadingonphotosyntheticandstomatalresponsesincottonleaveswasveryremarkable.

简介：发生在夏天期间的分散的雨事件在半干旱的草地的生物活动的开始起一个重要作用。为了理解一棵buffel草(CenchrusciliarisL.)的生态系统过程怎么统治了草地，对夏天雨事件作出回应，LI6400煤气的交换系统被用来测量叶气体交换，植物华盖房间被用来测量网生态系统公司2交换(旧姓)并且生态系统呼吸(R在雨前在时期期间顺序被做的eco),(干燥)并且在雨以后(湿)。粗野生态系统光合作用(GEP)被估计从旧姓并且Reco流动，和轻使用效率参数用一个矩形的双曲线模型被估计。在季风雨以前，草地生物资源非绿、干燥展出积极旧姓(碳来源)并且低GEP在土壤水在哪个期间变得逐渐地少见期间珍视。起始的雨脉搏(60公里)从季风前层次增加了NEE到否定旧姓(碳获得)与显著地更高的GEP和增加的绿生物资源。有气孔的传导力也是的叶光合作用和叶实质地改善了。最大的网公司2举起(即，否定旧姓)由于多重雨事件在随后的时期被支撑。作为结果，草地在第一雨以后为20d充当了一个网碳水池。与雨(弄干的周期)的停止，网公司2举起被减少降低价值。到雨的这块草地的高敏感建议在在夏天的降水的任何减少可以多半影响半干旱的生态系统的碳隐遁。

简介：AchangeintheEuropeanUnionenergypolicyhasmarkedlypromotedtheexpansionofbiogasproduction.Consequently,largeamountsofnutrient-richresiduesarebeingusedasorganicfertilizers.Inthisstudy,apotexperimentwasconductedtosimulatethehigh-risksituationofenhancedgreenhousegas(GHG)emissionsfollowingorganicfertilizerapplicationinenergymaizecultivation.WehypothesizedthatcattleslurryapplicationenhancedCO_2andN_2Ofluxescomparedtobiogasdigestatebecauseoftheoverallhighercarbon(C)andnitrogen(N)input,andthathigherlevelsofCO_2andN_2OemissionscouldbeexpectedbyincreasingsoilorganicC(SOC)andNcontents.Biogasdigestateandcattleslurry,atarateof150kgNH_4~+-Nha~(-1),wereincorporatedinto3soiltypeswithlow,medium,andhighSOCcontents(Cambisol,MollicGleysol,andSapricHistosol,termedClow,Cmedium,andChigh,respectively).TheGHGexchange(CO_2,CH_4,andN_2O)wasmeasuredon5replicatesoveraperiodof22dusingtheclosedchambertechnique.TheapplicationofcattleslurryresultedinsignificantlyhigherCO_2andN_2Ofluxescomparedtotheapplicationofbiogasdigestate.NodifferenceswereobservedinCH_4exchange,whichwasclosetozeroforalltreatments.SignificantlyhigherCO_2emissionswereobservedinChighcomparedtotheothertwosoiltypes,whereasthehighestN_2OemissionswereobservedinCmedium.Thus,theresultsdemonstratetheimportanceofsoiltype-adaptedfertilizationwithrespecttochangingsoilphysicalandenvironmentalconditions.

简介：植物枝条生物力学特性是研究植物地上部分防风抗蚀作用的基础。以内蒙古准格尔露天煤矿排土场平台和边坡上栽植的柠条、沙棘、紫花苜蓿、沙打旺、杨柴、草木犀6种常见水土保持植物的地上部分枝条为研究对象,研究枝条数量特征,确定其代表枝,从而为几种植物枝条生物力学性质的研究提供基础数据和相关参数。代表枝的确定将枝条以0.5mm为一个径级进行分级,分别计算每个径级组的累计枝数量比例、累计枝长比例、累计枝表面积比例和累计枝干质量比例,取这4个值相对较大的径级组作为各自的代表枝。结果表明：柠条代表枝径级为0.5～1和1～1.5mm,沙棘为1～1.5和1.5～2mm,杨柴为0～0.5和0.5～1mm,紫花苜蓿为0.5～1mm,沙打旺为0.5～1和1～1.5mm,草木犀为1～1.5mm。因此,在内蒙古准格尔采煤矿区及相似地区,在植物防风抗蚀生物力学性质的研究中,建议以上述6种水土保持植物作代表枝径级为主要研究范围。

简介：通过收集长江三峡库区22个区（县）30个退耕还林样地的调查数据,参考LY/T1721—2008《森林生态系统服务评估规范》,对其中6种主要退耕还林模式涵养水源与保育土壤效益及其价值进行评估。结果表明：1）三峡库区6种主要退耕模式总调节水量（即涵养水源量）达到11.6791亿t/a;调节水量的价值为68.37亿元/a,净化水质价值约为24.42亿元/a,涵养水源总价值约为92.79亿元/a;2）保育土壤总价值为0.9036亿元/a,其中马尾松林、落叶阔叶林、竹林、板栗林、柑橘林和茶林保育土壤的价值分别为1531万、2251万、1031万、2815万、1157万和251万元/a;3）三峡库区不同退耕模式取得的涵养水源效益和保育土壤效益都存在很大差别,因此,对三峡库区退耕还林工程生态效益不能只从总体上进行评价,还应该考虑不同退耕模式的生态效益,以便更好地评价和指导三峡库区退耕还林工程的实施;4）评价一种退耕模式的好坏,还要综合考虑多种生态效益。