Abstract:
A study was conducted to investigate contents of three main heavy metal elements, cadmium, lead and copper, in ramie (
Boehmeria nivea)and its associated soils in the Dexing Copper Mining of Jiangxi Province. Samples of soils and ramie were collected from 8 sampling sites typical of the mining area for analysis. Results show that the soil of the area has been severely polluted with Cu and slightly with Cd, but not Pb, which was found still within the range of soil background values of Jiangxi Province. In the soils around the 8 sampling sites, the mean content of Cd, Pb and Cu was 0.51, 9.36 and 1 058.21 mg·kg
-1, respectively. In most of the sampling sites, the content of heavy metals was the lowest in ramie leaves and the highest in ramie roots, and the difference between the highest and lowest was drastic, reaching a few dozen times. In terms of bioaccumulation coefficient and transfer coefficient in the ramie, the content of heavy metals displayed an order of Cd>Pb> Cu. The heavy metals varied sharply in bioaccumulation coefficient and transfer coefficient in ramie. The highest bioaccumulation coefficient and the highest transfer coefficient of Cd was 1.42 and 0.54, of Pb 0.63 and 0.53, of Cu 0.08 and 0.37, respectively. Of the eight sampling sites, the mean biomass of ramie shoot was 1.41 t·hm
-2, and the highest reached to 2.18 t·hm
-2. The mean bioaccumulation of Cd, Pb and Cu in the ramie was 0.2, 1.1 and 24 g·hm
-2, respectively. All the findings indicate that ramie is quite tolerant to Cu and Cd and can be grown as pioneer plant in mining areas for control of heavy metals pollution and phytoremediation of the ecology in the area.