模拟践踏对中位泥炭藓叶绿素荧光特性的影响范贝贝卜兆君刘超胡雪凤陈永达摘要：該研究以采自长白山区月亮湾湿地开阔地的红型和林缘的黄绿型中位泥炭藓（Sphagnummagellanicum）为材料，室内模拟人为践踏，使用便携式调制叶绿素荧光仪，测定其叶绿素荧光参数，探讨了不同践踏强度、不同践踏轮次下，两类中位泥炭藓的荧光参数响应情况。结果表明：至第二轮践踏，红型中位泥炭藓的PSⅡ实际光量子产量[Y（Ⅱ）]和相对电子传递速率（ETR）随践踏强度增大而减小，而黄绿型的践踏组均大于对照组;践踏结束时，红型的Y（Ⅱ）和ETR的践踏组均显著低于对照组，而黄绿型只有轻度践踏低于对照组;黄绿型泥炭藓践踏组的非调节性能量耗散量子产量[Y（NO）]甚至要低于对照组。这表明尽管泥炭藓属植物能耐受一定的践踏胁迫，但随着践踏轮次增多、强度增大，胁迫累积效应将强烈抑制其生长;多见于开阔地的红型泥炭藓对人为践踏的耐受能力低于林缘生境的黄绿型泥炭藓。湿地保护与管理中，应减少游人践踏干扰，尤其要严格控制开阔地生境的游人进入。Key：人为践踏，苔藓植物，叶绿素荧光参数，湿地，泥炭EffectofsimulatedtramplingonthechlorophyllfluorescencecharacteristicsofSphagnummagellanicumFANBeibei1，2，BUZhaojun1，2*，LIUChao1，2，HUXuefeng1，2，CHENYongda1，2（1.KeyLaboratoryofGeographicalProcessesandEcologicalSecurityinChangbaiMountains，MinistryofEducation，SchoolofGeographicalSciences，NortheastNormalUniversity，Changchun130024，China;2.StateEnvironmentalProtectionKeyLaboratoryofWetlandEcologyandVegetationRestoration，InstituteforPeatandMireRsearch，NortheastNormalUniversity，Changchun130024，China）Abstract：Redandyellow-greenSphagnummagellanicumshootsgrowingintheopenareaandforestmarginofYueliangwanwetland，respectively，intheChangbaiMountainswerechosenasstudymaterials.Aportablepulse-amplitudemodulationfluorometerwasusedinthisstudytomeasurechlorophyllfluorescentparameters.WeanalyzedthefluorescentresponsesofthetwotypesofS.magellanicumshootstotramplingintensitiesandtramplingroundsbysimulatinganthropogenictramplingindoor.EffectivePSⅡquantumyield[Y（Ⅱ）]andelectrontransportrate（ETR）ofredS.magellanicumdecreasedwithtramplingintensityincrease，whilethoseofyellow-greentypeincreasedwithtramplinginthesecondroundoftrampling.Y（Ⅱ）andETRofred-typeS.magellanicumunderanthropogenictramplingweresignificantlylowerthanthoseincontrolgroup，whileforyellow-greentypetheyunderlightlytramplingwerelowerincomparisontothoseincontrolgroup.Non-regulatedenergydissipation[Y（NO）]ofyellow-greenS.magellanicumdecreasedwithtrampling.OurresultsindicatethatSphagnumcantoleratecertaintramplingstress，butitsgrowthwillbestronglyinhibitedbythecumulativeeffectofthestress.Ourstudyalsosuggestthatyellow-greenS.magellanicuminforestmarginismoretoleranttotramplingthanred-typeintheopenarea.Touristtramplinginwetlandsespeciallytheopenareashouldbereducedorevenstrictlyforbiddenintheprotectionandmanagementofwetlandsinthefuture.Keywords：anthropogenictrampling，bryophyte，chlorophyllfluorescenceparameters，wetland，peat随着自然景观开发力度逐年增强，人为践踏对植被盖度、物种组成多样性均产生不良影响，甚至引起外来物种或杂草入侵风险的增加，加剧了生态系统的退化（Pertierraetal.，2013;Barrosetal.，2013）。目前，对于践踏胁迫的研究主要集中在维管植物方面（Pescott&Stewart，2014）。泥炭藓属（Sphagnum）植物作为大多泥炭地的主要固碳植物，对于全球的碳循环具有重大意义（Mcneil&Waddington，2003）。该类植物没有根作支撑，茎的细胞构造也较为单一，无维管束构造，疏导作用不强，受到践踏的威胁可能更严重，而日益增多的游人所造成的人为践踏对泥炭...