Screening Of Manganese Tolerant Plants And Research Of The Methods For Remediation Of Manganese Contaminated Soils

The tail residuals collected from Xiangtan Manganese Mining area was used as medium for plant growth for screening of manganese tolerant plants and comparision the methods for remediation of manganese contaminated soils. The objective of this study is to find adequate plant species and to develop proper soil remediation methods that can be applied in bio-remediation of the manganese contaminated soil in Xiangtan area. The main results obtained from this study are summarized as follows:(1) According to the pot experiment for11months, preliminary screened11kinds of plant species covered five functional category which have the potential ability to resist manganese pollution. Among all, the pioneer plant is Abelia dielsii, timber plants are Phoebe zhennan S.Lee et F.N. Wei and Castanopsis sfissa, industrial raw material plants are Cinnamomum parthenoxylon(Jack) Nees and Broussonetia papyrifera, landscape plants are Ligustrum quihoui Carr, Distylium racemosum Sieb.et Zucc and Daphniphyllum calycinum Benth, and the energy plants are Sapium sebiferum, Pistacia chinensis and Swida wilsoniana. These plants can be used as optional plants for manganese contaminated soil ecological restoration.(2) Compared with the controlled experiments, improved treatment (80%original residue+10%soil+5%peat soil+5%organic bacterial manure) can improve the screened plants' survival rates and mass growth notably.(3) The survival rates and mass growth status of Cinnamomum parthen o-xylon (Jack) Nees in all improved treatment are better than controlled treatment in the further developed contrast test of different improved formula. The total biomass on the ground and underground part of Cinnamomum parthenoxylon (Jack) Nees have negative correlation with the total content of Mn, Pb, Zn, Cu, Cd in soil, it have the most significant negative correlation with the content of Mn and Cu in soil; the plant's height decreased with the contents of Mn, Pb, Zn, Cu, Cd content in soil increased, the Mn content in soil have the most significant negative effect to plant's height growth; the correlation coefficient between root length and Mn content in soil is-0.74. Among other heavy metal elements, Pb have more influences, explained that the Pb elements is also one of the important factors to restrain Cinnamomum parthenoxylon(Jack) Nees' growth. (4) The improved treatment of adding15%of the red soil and5%of the organic bacterial manure is the best pollution matrix improved plan.