三峡水库156m蓄水后消落带新生湿地植物群落-王强

三峡水库156m蓄水后消落带新生湿地植物群落＊王强1,2袁兴中1,2＊＊刘红1王建修3(1重庆大学资源及环境科学学院,重庆400030;2西南资源开发及环境灾害控制工程教育部重点实验室,重庆400030;3重庆市开县澎溪河湿地自然保护区管理局,重庆开县405400)摘要三峡水库156m蓄水后,已形成大面积消落带湿地。2008年7—9月对地处三峡水库腹地的开县澎溪河左岸一级支流白夹溪消落带新生湿地植物进行了调查。结果表明:该区域共有高等湿地植物33种,优势种有双穗雀稗、宽叶香蒲、萤蔺、藨草、长鬃蓼。新生湿地植物群落划分为8个群丛。沿河流侧向空间梯度,湿地植物群落的带状分布明显,分为河漫滩1年生草本植物带、苍耳带、双穗雀稗带3个植物带。从河岸到海拔156m处,植物地上生物量呈现出先增加后减少再增加的趋势。消落带区域在水位下降后,土壤含水率的增加为湿地植物生长提供了良好生境。双穗雀稗成为156m蓄水后白夹溪河岸二级阶地地势低洼处的优势植物;苍耳在河岸一级阶地和二级阶地之间的坡地上广泛分布。三峡水库蓄水后消落带土壤含水率的变化、微地貌格局对消落带新生湿地群落空间格局具有明显影响。关键词三峡水库;消落带;新生湿地;植物群落中图分类号Q145文献标识码A文章编号1000-4890(2009)11-2183-06Plantcommunitiesinnewlycreatedwetlandsinwater-levelfluctuationzoneofThreeGor-gesReservoirafterfloodingto156mheight.WANGQiang1,2,YUANXing-zhong1,2,LIUHong1,WANGJian-xiu3(1CollegeofResourcesandEnvironmentalScience,ChongqingUniversity,Chongqing400030,China;2KeyLaboratoryofSouthwestResourceExploitationandEnvironmentalDisasterControllingEngineeringofEducationalMinistry,Chongqing400030,China;3PengxiRiverWetlandNatureReserveManagementBureau,Kaixian405400,Chongqing,China).ChineseJournalofEcology,2009,28(11):2183-2188.Abstract:Afterfloodingto156mheight,awideareaofwetlandsemergedinthewater-levelfluctuationzoneofThreeGorgesReservoir.FromJulytoSeptember2008,aninvestigationwasmadeontheplantcommunitiesbesideBaijiastream,thefirstordertributaryofPengxiRiverinKaixianCountyofChongqing.Therewere33speciesofwetlandvascularplants,amongwhich,Paspalumpaspaloides,Typhalatifolia,Scirpusjuncoides,S.triqueter,Polygonumlongisetumwerethedominant.Theplantcommunitiesinstudyareaweredividedintoeightassociations.AnobviouszonaldistributionwasobservedatthelateralsideofBaijiastreamfromriparianto156maltitude.Therewerethreeplantzones,i.e.,floodplainannualherbzone,X.sibiricumzone,andP.paspaloideszone.Withincreasingelevation,theabovegroundbiomassshowedasingle-peakpattern.Duringtheperiodwithlowerwaterlevel,theincreaseofsoilwatercontentacceler-atedthegrowthofwetlandplants.P.paspaloideswasmostdominantinthelow-lyingareaofsec-ondterracesofBaijiastream,andX.sibiricu