九龙江口红树植物叶片重金属元素含量及动态
Content and dynamics of Five heavy metals elements in the leaves of Five mangrove species in Jiulong Estuary
Abstract
本文探讨了福建九龙江口潮间带秋茄(kAndElIACAndEl)、木榄(bruguIErAgyMnOrrHIzA)、红海榄(rHIzOPHOrASTylOSA)、白骨壤(AVICEnnIAMArInA)和桐花树(AEgICErASCOrnICulATuM)等红树植物叶片重金属元素Cu、Pb、zn、Cd、Mn的含量及动态。结果表明,该河口红树林区表层土壤沉积物元素含量顺序为Mn>zn>Pb>Cu>Cd;5种红树植物叶片元素含量顺序为Mn>zn>Cu>Pb>Cd;不同物种叶片元素含量大都有明显差异;叶片对土壤元素富集系数,以Mn、Cd较高,Pb最低;随叶片从幼叶-成熟叶-黄叶的生长发育,Mn、Pb、Cd含量上升,而Cu、zn则下降;叶片重金属元素含量随季节的变化而变化,变化规律因物种及元素种类而异。红树植物叶片对林地土壤重金属元素的富集能力是低的,这有利于对各级消费者提供大量洁净的食物。 The paper deals with the content,seasonal and developmental dynamics of heavy metalselements: Cu, Pb, Zn, Cd and Mn in the leaves of Kandelia candel, Bruguiera gymnorrhiza,Rhizophora stylosa,Avicennia marina and Aegiceras corniculatum in the Jiulong Estuary.Theresults are indicated as Follows.1) The content order of the elements in the surFace sedimentsof the region is Mn>Zn>Pb>Cu>Cd,and that in the leaves of the Five mangrove species isas Follows: Mn>Zn>Cu>Pb>Cd; 2)There are signiFicant diFFerences in the contents of eachelement in diFFerent species; 3)The enrichment coeFFicients of the leaves to the metal elementsin the surFace sediments are low,relatively higher For Mn and Cd,and the lowest For Pb; 4)with the development of the leaves From mature to Fall,the contents of Mn,Pb and Cd rise,but Cu and Zn decrease; 5) The contents of the elements in the leaves change with speciesand season.Though the existence of mangroves may promote the depositlon and Fixation ofthe heavy metal elements in the sediments of the region,they can produce large amounts ofuncontaminated leaves For the consumers of the ecosystem.