Study On Distribution Characteristics Of Heavy Metals In Woody Plants Of Environmental Remediation In Huainan Mining Area

Huainan is a mining city, which brings about certain influence on the surrounding environment while developing the mineral resource, in which more serious heavy metal pollution in soil is one of the important reasons to lead to the destruction of the environment. In this paper, the three reclamation areas of the Panyi, Datong and Xin Zhuangzi were treated as the study objects.The content distribution of heavy metals in different woody plants and content distribution of heavy metals in plant organs were studied, in order to identify the characteristics of accumulation and tolerance of different plants in reclamation area to heavy metal. As a new technique, phytoremediation is applied and promoted in the areas of heavy metal pollution governance. But some hyperaccumulators are limited mainly in herbaceous and aquatic plants. Through the study of characteristics of woody plants uptake and accumulation of heavy metal content, the following conclusions were given:1. Fir, poplar, cedar, maple, Loropetalum, Amorpha, and gold leaf privet are with higher Cu content in the body, and the enrichment coefficient is over 1.0, with better concentration ability, and with more strong patience on the Cu content, Spain large-leaved oak, big leaf gardenia and jin belt have low level of accumulation of Cu, Cu content in general plants is below the average concentration. Cu in roots is higher than aboveground of metasequoia, maple, redrlowered loropetalum, gold leaf privet. As direct-type plants, poplar and cedar mainly accumulate Cu in the branches and leaves, with better transport ability, is the rich set-type plants.2. Zn level in woody plants is lower than average concentration of normal plants. The enrichment factors of some of poplar, ligustrum lucidum aiton and Sichuan cypress are above 1.0, The enrichment factors of other plants are below 1.0, poplar, ligustrum lucidum aiton and Sichuan cypress have relatively strong enrichment ability of Zn, Spain fissa, the dough rose have a low level, is evade-type plant. Distribution of Zn content in plant organs is:overground>underground, showing a certain degree of upward transport capacity.3. Cr and Ni content in plants of two reclamation area are analyzed, above the average level of Cr and Ni content in common plants. Such as Sichuan cypress, Spain large-leaved oak, dough rose, cedar and poplar, although the enrichment coefficient is small, but still have large accumulation of more bio-Cr and Ni elements, can be considered as repair plants in mining area with soil contaminated by Cr, Ni. Enrichment factor of poplar leaves in some areas is above 1.0, Cr elements maybe absorbed by leaves from the air. In addition to branches of cedar and Ligustrum are the main organs to accumulate Cr, other plants accumulating Cr order:root> branch> leaf, The distribution regularity of Ni in plant organs is not obvious, Distributions of Ni content in different plant organs are significantly different.4. California Privet, Citrus trees, fir, big leaf gardenia and ligustrum lucidum aiton have relatively high content of Pb in body, but mainly in the parts aboveground, of which branch of California Privet enrichment coefficient is above 1.0, with strong ability of accumulate and transport, enrichment factor of Citrus trees and ligustrum lucidum aiton is above 0.5, can be the first choice as the repair plants in area polluted by Pb. Pb content in root of Dough roses, acacia and peach was lower, enrichment coefficient is small, and the enrichment factor branches is more over than roots, can resist the Pb to be absorbed into the body, belonged to evade-type plant.5. Cd in poplar, Sichuan cypress and metasequoia is relatively high, enrichment factor is above 1.0, the concentration ability is strong, enrichment factor of organ aboveground is more over than underground, ability of upward transport is strong, as Cd-enrichment type plants, could be treated as repair plant in areas contaminated Cd, Ligustrum lucidum aiton, cedar, tree of heaven, Neem also has a certain ability of accumulation and transportation, which has potential to repair soil contaminated by Cd.6. Cr and Ni have significantly relativity in plant roots in Panyi reclamation area, relativity of Cu and Pb is not obvious. relativity of Ni and Cu, Cr in plant roots of Datong Reclamation District is obvious, relativity of Cu and Zn is not obvious, and correlation coefficient of other heavy metals in plant roots is lower pairwise, some is negative, correlation is not obvious.