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2005200062cjbi@geo.ecnu.edu.cn“”2002~20031612002CuPbMnZnCr3425t/a2751t/a34.5×105t/a69505t/a14045t/a3176t/a0mCuPbFeMnZnCr24.3%27.6%32.3%32.4%20.5%23.2%DDXs100871shchen@pku.edu.cn220048118)()11(1234512345)(12345123456)()p,p’-DDEp,p’-DDDp,p’-DDTDDXsDDXsDDXsDDXsDDXsDDXsDDXsp,p’-DDEp,p’-DDDp,p’-DDTKoaKoc974000974zueer@mail.ndhu.edu.t@stu.snnu.edu.cn6800mg/L7.5mg/L2.3mg/L;pHRootexudatesoflow-molecularweightorganicacidsinwhitelupin(Lupinusalbus)andrape(Brassicanapus)atdifferentPlevelsGaoXiaojiangDepartmentofEnvironmentalScienceandEngineering,FudanUniversity,Shanghai,200433,xjgao@fudan.edu.cnThepresentstudyinvestigatedrootexudationoflow-molecularweightorganicacids(LMWOAs)inrootsofwhitelupin(Lupinusalbus)andrape(Brassicanapus)growninahydronicculturesystemunderdifferentPlevels(0,10,250µMP).UnderthelowPcondition,thepHofnutrientsolutioninwhitelupinclearlydecreased,butthepHinrapebecameincreasebycontraries.Ontheotherhand,severalPdeficiencyphenomenasuchasreducedshootgrowthandleafnecrosis,occurredduringthehydroponicculture.Thus,thetotalbiomassofwhitelupinandrapewasstronglyreducedunderPdeficientcondition(10and0Plevel),Besidetheobviousdifferentbiomassofeachplantshootandraperoot,thereisalmostnochangeforthebiomassofwhitelupinrootwhichispossiblebecauseofitsspecialclusterrootsystem.AnalysisresultsofLMWOAsshowthatthereisalargerincreaseofLMWOAconcentrationintherootofwhitelupinunderlowerPlevel,whichisabout25~28timesmorethanthatofwhitelupinat250µMPcondition.WhereasthetotalLMWOAamountofrootexudationofrapepresentnobigchangeunderdifferentPcondition.ThissuggestthatPdeficiencycanstronglyinducedrootexudationofLMWOAsinrootofwhitelupin,butthereisnoclearlyeffectontherootexudationofrape,whichisassociatedwithdifferentpHchangesofnutrientsolutionofwhitelupinandrapeplants.CitricacidandmalicacidwastwoofthemajorLMWOAsexudatedintherootofwhitelupininresponsetoPdeficiency.ThedistributionofLMWOAsinrootexudationofrapeisonlowerconcentrationcomparedwiththatofwhitelupin.TheresultsindicatethatPdefiency–inducedchemicalchange(pH,LMWOAs)inrhizosheresystemstronglydependsonplantspeciesandvariousrhizosphereprocesses.@urban.pku.edu.cn8/(1h720h)Freundlichn1/48h/FreundlichKF8nKoc*(LAS),,,,,,100871liuxl@pku.edu.cn,(PAHs):(pyr)las0.2mg/l,3mg/lLASpyr11,217100622710075yuliuxq@hotmail.com1989~2003198961.66200347.039%43.2%33%:@fjnu.edu.cn2350007/H3PpH——DOpHL934-60~65%35~40%70~85%pH18-----0.907 5.458mg/m2.d,1.129 4.039mg/m2.d0.794 2.046mg/m2.d11121200062juansun_ecnu@126.com2200030juansun_ecnu@126.com6Davis2000@126.comNASAMODIS10km7002070OMIS-I2002107OMIS515nm~577nm0.214~0.417LOWTRAN1,211100875wangjue@ires.cn210087590GDP7%“”EKC1992~200329EKC“U”1978GDP13000/4546/“U”~2003PAHs111122221100871xjwang@urban.pku.edu.cn230019118816PAHspHPAHsPAHsPAHs0~5km5~10km10~50kmPAHsPAHsPAHsCFD1,1,21100086wanghonglin@vip.163.com2CFDCFDCFDPHOENICSPOWERBUILDERVC++SIMU_DDCZRHJSIMU_DDCZRHJCFDCFDCFDCFDDLLCFDCFDWINS32APICFDRDBMSCAD@urban.pku.edu.cnRERI123419861995200334.712.23kmRERIRERI,liminyang@cuhk.edu.hk.12345,,11,21710062,yuyaochuang@126.com27100751989~200214,“”@nuigalway.ie23GIS16,51127-(Q-Q)Q-Q(Al,Ca,KNa)Q-QQ-QQ-Q27:(1000)Q-Q,100871,zuoqian@pku.edu.cnASEGC-MS30216EPAPAHsPAHs(TOC)16EPAPAHs24.83ng/g~8420.90ng/g,856.00ng/gPAHs2~3PAHs2~3PAHs32~3PAHs5~6PAHs65~6PAHs