碱蓬（Suaeda salsa）对胶州湾滨海湿地重金属的富集与迁移作用

摘要

Accumulation and transportation of heavy metals by Suaeda salsa were studied in the northeastern coastal wetland of the Jiaozhou Bay.The uptake of Cu and Zn in S.salsa was much higher than other metals due to their essential roles in plant growth and development.For other metals,the concentrations of Cr,Pb,V,and Ni in S.salsa were relatively higher than Cd,As,Mo,and Co.However,accumulation of Mo by Suaeda salsa was the most obvious relative to its content in the soil,and the enrichment factors was higher than 1 in all sampling stations.The orders of enrichment factor of the heavy metals in root,stem and leaf were Cd As Cu Zn Mo Co Ni V Pb Cr,Mo Cd Zn Cu As,Co,Ni Pb,Cr V and Mo Cd Zn Cu As Ni Co Pb,Cr V,respectively.Overall,Mo and Zn were transported from underground to aboveground tissues and their concentrations in stem and leaf were 66.3% and 65.9% higher than in the root,respectively.The concentrations of Cu,Pb,Cd,Cr,Co,and Ni in underground and aboveground tissues were similar,while the transportation efficiencies of As and V were lower.Their concentrations in stem and leaf were only 33.5 and 37.2%,respectively.%通过对胶州湾东北部滨海湿地5个采样点生长的碱蓬中10种重金属Cu、Zn、Pb、Cd、As、Cr、Co、Ni、V、Mo的系统研究,发现碱蓬对Cu,Zn的吸收明显高于其它重金属,这可能与Cu和Zn是植物生长发育必需的微量元素有关,碱蓬体内Cr、Pb、V和Ni的含量也相对较高。碱蓬对Mo的富集效果最为显著,对Cu、Zn、Cd和As也表现出一定的富集作用,而对其它重金属的富集效果不明显。碱蓬的根、茎和叶对重金属的富集系数从大到小依次为：Cd〉As〉Cu〉Zn〉Mo〉Co〉Ni〉V〉Pb〉Cr;Mo〉Cd〉Zn〉Cu〉As,Co,Ni〉Pb,Cr〉V;Mo〉Cd〉Zn〉Cu〉As〉Ni〉Co〉Pb,Cr〉V,总体而言,碱蓬对Mo和Zn的迁移效率较高,大部分被迁移至地上部分,输送到茎叶的平均相对含量分别占66.3%和65.9%,其次是Cu、Pb、Cd、Cr、Co和Ni,它们在碱蓬地上和地下部分的比例大致相当,而碱蓬对As和V的迁移效率最低,输送到茎叶的平均相对含量分别只有33.5%和37.2%。