汉源铅锌矿区植物对Pb和Zn的积累及耐性研究

Heavy-metal Accumulation and Tolerance of Plants at Zinc-lead Mine Tailings in Hanyuan

采取野外调查与实验分析相结合的方法,对汉源3个典型矿区内17种优势植物中Pb和Zn的吸收富集特点进行了分析。结果表明,17种植物对Pb和Zn的吸收有较大差异,其中:星毛角柱花、籽粒苋的地上部分和曼陀罗的地下部分对Pb的积累较好,积累含量分别为331.63、226.44和253.13mg·kg-1;新樟的地下部分和银柳的地上部分对Zn的积累能力较强,积累含量分别达到1068.40和823.32mg·kg-1;蔗茅的地下部分以及大乌泡的地上部分对Pb和Zn均表现出较强的富集能力,其Pb积累含量分别达到455.75和673.52mg·kg-1,其Zn含量为1317.62和893.34mg·kg-1。同时,籽粒苋、卷柏、蜈蚣草、冬青对Pb和Zn以及新樟对Pb的生物迁移系数均大于1,尤以新樟对Pb和卷柏对Zn的生物迁移系数最为突出,分别高达15.88和8.44。虽然所有植物均未达到超富集植物临界含量要求,但其部分体内已形成耐性,成为Pb和Zn耐性植物,其中蔗茅、大乌泡、新樟、籽粒苋和曼陀罗5种植物,可以作为潜在的Pb和Zn污染修复物种。

The concentrations and enriching abilities of Pb and Zn in 17 dominant species growing on the 3 typical Zinc-lead mine tailings in Hanyuan were analyzed. The results showed that the concentrations of Pb and Zn among 17 species were obviously different. The shoots of Ceratostigma griffithii and A maranthus hypochondr/cus L., the roots of Datum Stramonium L. exhibited higher accumulation abilities for Pb, with the concentration 331.63 mg·kg^-1, 226.44mg·kg^-1 and 253.13 mg. kg-I respectively. The concentrations of Zn in the roots of Neocinnamomumparvifolium reached 1 068.40 mg·kg^-1 and 823.32 mg·kg^-1 in the shoots of Salix. In the roots of Erianthus rufipilus and in the shoots of Rubus multibracteatus, the concentrations of Pb were 455.75mg·kg^-1, 673.52 mg·kg^-1, and the concentrations of Zn were 1 317.62 mg·kg^-1, 893.34 mg·kg^-1 respectively. At the same time, the biological transfer coefficients of Pb and Zn in Amaranthus hypochondricus L., Selaginella tamarisina, Pteris.vittata and that of Pb in Neocinnamomumparvifolium were all higher than 1, especially the biological transfer coefficient of Pb in Neocinnamomumparvifolium and that of Zn in Selaginella tamarisina were remarkably high, being up to 15.88 and 8.44, respectively. The concentrations in all 17 species did not reach the standard of hyperaccumulator, but some of them already became the metal-tolerant plants to Pb and Zn. Erianthus rufipilus, Rubus multibracteatus, A maranthus hypochondricus L., Dature Stramonium L. and Neocinnamomumparvifolium would be very useful in the restoration of Pb and Zn polluted areas.