洱海地区一万多年以来气候环境演化的湖泊沉积记录

152Vol.15,No.220036JournalofLakeSciencesJun.,2003*1*2105Fig.1TerrainofErhailakeandthelocationofEScore10615Fig.2RelationshipbetweenageanddepthinEScore210710815210911015(3)2111AllDentonGA,KarlenW.Holoceneclimatevariations,theirpatternandpossiblecause.QuatRes,1970,3:155-20515RothlisbergerF.10000JabreGletschergeschichtederErdeArau.Verlag:Sauerlander,1986WClimaticandEnvironmentalChangesfromtheSedimentRecordofErhaiLakeoverthePast10000YearsZHOUJing1,2,WANGSumin1&LÜJing3(1:NanjingInstituteofGeographyandLimnology,ChineseAcademyofSciences,Nanjing210008,P.R.China;2:GraduateSchoolofCAS,Beijing100039,P.R.China;3:InstituteofBotany,ChineseAcademyofSciences,Beijing100093,P.R.China)AbstractErhaiLake,formedbyfaults,isthesecondlargestfreshwaterlakeonthenorthwesternYunnanPlateau,southwesternofChina.Theareaisinfluencedbysoutheastmonsoon(fromBengalGulf),theprecipitationbetweenMarchandOctoberaccountedfor70%-90%ofayear.Annualaveragetemperatureis15.1.EScorewithalengthof6.62mwastakenfromthedeep-waterareainthenorthernpartofthelakebasininApril,2001.Basedontheanalysisofhighre-solutionandmulti-environmentalproxiesofthiscore,includingAMSdating,pollen-spore,grainsize,algaandcarbonfragment,elevenphasesofclimaticandenvironmentalchangeshavebeenidentified.Asaresult,theregionalpaleoclimateandpaleoenvironmentarereconstructedoverthepast10000years.Fourglobalcoldeventswerewellrecorded,whichhappenedin9.9kaBP,8.5kaBP,7.1kaBPand5.1kaBP.Thesecoldeventscanbecomparedtothosehappenedindiffer-entpartsoftheworld.Theperiodfrom6.8kaBPto5.5kaBPwastheoptimumperiodwithwetandwarmclimateinHolocene.Obvioushumanactivitiesbeganfrom2.4kaBPinthisregion.Keywords:ErhaiLake;multi-environmentalproxies;coldevents;evolutionofenvironmentandclimate;humanactivities