土壤重金属沿山地森林海拔梯度的分布特征

Distribution Characteristics of Heavy Metals along an Elevation Gradient of Montane Forest

采用电感耦合等离子体发射光谱法与石墨炉原子吸收光谱法,研究了14种重金属(Fe,Al,Ti,Cu,Cr,Mn,V,Zn,Ni,Co,Pb,Se,Cd,As)沿山地森林海拔梯度的分布特征。结果表明海拔梯度对14种重金属中的6种重金属浓度(Fe,Al,Ti,V,Pb与As)有显著的影响,对其他八种重金属浓度(Cu,Cr,Mn,Zn,Ni,Co,Se,Cd)没有显著的影响。由于研究区域为红壤,海拔梯度对红壤特征重金属Fe,Al与Ti浓度有显著影响,表明不同海拔高度红壤存在不同强度的脱硅风化过程与生物富集过程。此外,海拔梯度对其他重金属存在不同的影响,如Cr,Zn与Cd在较高海拔有较高浓度,Pb与As在较低海拔有较高浓度,表明不同海拔高度的森林土壤受重金属污染的主要类型不同。

In the present paper,the concentrations of fourteen heavy metals（Fe,Al,Ti,Cu,Cr,Mn,V,Zn,Ni,Co,Pb,Se,Cd and As）were determined by ICP-AES and atomic absorption spectroscopy along an elevation gradient of montane forest.The results show that the elevation gradient had significant effects on the concentrations of Fe,Al,Ti,V,Pb and As.And theconcentrations of Cu,Cr,Mn,Zn,Ni,Co,Se and Cd were not significantly affected by the elevation gradient.Because thestudying area is red soil,the elevation gradient had significant effects on the concentrations of Fe,Al and Ti which are character-istic heavy metals of red soil,suggesting that the red soil at different elevations has different intensities of weathering desilicationand bioaccumulation.Other heavy metals have different relationships with the elevation gradient,such as the concentrations ofCr,Zn and Cd were high at relatively high elevation and Pb and As were high at relatively low elevation.These results suggestthat the different elevations of montane forest soils were polluted by differently types of heavy metals.