泉州湾红树植物中重金属元素的分布与储量

用ICP-AES测定了泉州湾洛阳江河口红树植物桐花树(Aegiceras corniculatum)和秋茄(Kandelia candel)根际沉积物中重金属总量和有效态含量,以及这2种植物体内重金属的含量,探讨了该红树林湿地重金属元素的分布、富集和储量情况。结果表明,2种红树植物根际沉积物中重金属总量均表现为:Fe>Mn>Zn>V>Pb>Cr>Cu>Ni>Co>Cd,有效态含量均表现为:Fe>Mn>Zn>Pb>Cu>V>Cr>Ni>Co>Cd,部分重金属具有一定潜在的有害生物效应;Fe、V在2种红树植物根部的含量最高,Mn在叶中的含量最高,其余重金属未有明显的统一规律;相关性分析表明,2种植物根中Cu和Zn,Pb和V、Co、Ni,Cr和Zn,Zn和V,V和Co、Ni,Co和Ni之间互有明显协同作用;除Mn在叶中存在较强的富集能力(富集系数大于1),2种红树植物对其余重金属元素的富集能力均较小,远达不到超富集植物的要求;秋茄和桐花树对Mn从根向叶的迁移能力最强,Cu、Cr、Zn在2种植物中的迁移系数均大于1,Cd在桐花树中的迁移系数也大于1,说明2种植物都有将这些元素向叶中输送的趋势,应注意其通过食物链富集作用引起的危害。2种红树植物中重金属总储量大小表现为:Mn>Fe(秋茄则Fe>Mn)>Zn>Cu>Cr>Pb>V>Ni>Co>Cd,其中Mn和Fe的总储量之和分别占到了总储量的97.7%(桐花树)和99%(秋茄)。

Distribution and Stock of Heavy Metals in Mangroves Growing in Quanzhou Bay

Distribution,enrichment and stock of heavy metals in Aegiceras corniculatum and Kandelia candel were studied through determining the contents of acid extractable and total heavy metals by ICP-AES in rhizospheric sediments and mangroves plants,which were collected from Luoyang estuary of Quanzhou Bay.Results showed that total contents of heavy metals decreased in the order of Fe,Mn,Zn,V,Pb,Cr,Cu,Ni,Co,Cd,while acid extractable contents decreased as Fe,Mn,Zn,Pb,Cu,V,Cr,Ni,Co,Cd.Some heavy metals had potentially toxic biologic effect,Fe and V were the highest in root,Mn in leaf,while others had not obvious regularity.Correlation analysis showed that Cu and Zn,Pb and V,Co,Ni,Cr and Zn,Zn and V,V and Co,Ni,Co and Ni had significant synergies in the roots of the two plants.The two plants had not enough accumulation abilities of heavy metals,except Mn in leaves with bio-concentration factor of larger than 1.0.The transfer ability of Mn in the two plants was the most powerful.The transfer factors of Cu,Cr and Zn in both mangroves(Cd in Aegiceras corniculatum) were also more than 1,which indicated that the two plants had strong ability to transfer heavy metals from root to leaf,and the harm of heavy metal enrichment through food chains should be paid attentions.Total stock of heavy metals in two mangrove plants decreased as Mn,Fe(while Fe,Mn in Kandelia candel),Zn,Cu,Cr,Pb,V,Ni,Co,Cd.Total stocks of Mn and Fe were higher than others with sum stocks of these two elements of 97.7% in Aegiceras corniculatum and 99% in Kandelia candel respectively.