关键词: 矿冶废弃地, 重金属, 超富集植物, 耐受性

Abstract:

Tonglushan Mine, located in the Southeastern part of Hubei Province,China, is one of the six copper mines in China and has more than 3 000 years history in mining.A lot of higher plants are growing on an ancient copper spoil heap (3 000 years old) on Tonglushan.Some of the plants are superior in number.Significant correlation may exist between the amount of heavy metals in these dominant plants and that in related soil. In order to provide scientific basis for the vegetation restoration of deteriorative ecosystem in mining districts and phytoremediation of soil polluted by heavy metals,the accumulation and distribution of heavy metals in some dominant plants growing on Tonglushan mineral area were investigated via field survey and sample analysis.Five dominant species including 〖WTBX〗Commelina communis,Elsholtzia haichowensis,Silene fortunei,Polygonum perfoliatum〖WTBZ〗 and 〖WTBX〗Kummerowia striata〖WTBZ〗 were found to have high concentration of total Cu,Pb,Zn,Cd,Cr.In particular,Cu had a high concentration in the root of 〖WTBX〗Elsholtzia haichowensis〖WTBZ〗,being at 84465 mg/kg,which is 338~1689 times higher than the general content in plants (5~25 mg/kg).But the concentration of total As in these species was 018~098 mg/kg,lower than the average in general plants.It can be deduced that these species have a kind of mechanism to evade assimilating As from soil.It is indicated that 〖WTBX〗C.commelis,E.haichowensis,S.fortunei,P.perfoliatum〖WTBZ〗 and 〖WTBX〗K.striata〖WTBZ〗 were not the hyperaccumulator for heavy metals Cu,Pb,Zn,Cd,Cr and As,but they were highheavy metalstolerant species.Moreover, these species will play an important role in vegetation restoration of abandoned mine sites.

Key words: abandoned mine sites, heavy metals, hyperaccumulator, tolerance 〖