The Potential Of Bioremediation In Tongling Mining Area And Evaluation Of Heavy Metals Pollution In Edible Crop

The vegetation in Tongling minging area has vegetal characteristics in the area of Yangtse River. There are appropriate natural root and extremely ecological environments for hyperaccumulator growing in Tongling mining area, and hyperaccumulator, bioindicator, metal-tolerant plants are propitious to be variated and evoluted. For the sake of providing academic supporting, the paper chooses reasonably out pioneer plants which were natural colonized, and discusses the potential of bioremediation. What is more, by using Potential Envirnment Risk Index, Pollution Load Index and Mistiness Mathematics Index, the paper evaluates the contaminative status of heavy metals in edible crop which grow in Tongling mining area. Leading conclusions:(1) In comparison with background level, the content of the corresponding heavy metals is higher in the corresponding inedible plants, and is lower in the edible crop. Different crop has higher selectivity of the accumulation on the heavy metals. The accumulation of different heavy metals content is differentia in the conspecific crop.(2) The content of heavy metals decreases in the order: Foliage vegetable >Rhizomatic crop >Seed-corn. For the sake of abating the contaminative effect of heavy metals, it is suggested that we should plant Seed-corn in those areas which are contaminative badly, such as: Oryza sativa and Cotton.(3) Accumulative characteristic: The accumulative abilities of these elements in most inedible plants decrease in the order: Cd>Hg>Pb> Zn>As>Cu>Cr. the accumulative abilities of these elements in edible crops decrease in the order: Cd> Hg> Zn> Cu> As> Pb> Cr(4) Transportable characteristic: The rate of heavy metals transport in Typha arientalis Presl and Radish is all more than 1, and the rate of Cr in imperata cylindraca var.Major is more than 1, whereas the heavy metals transportable rate of Setcreasea Pallida, Artemisia capillaries, Bermudagrass, Bidens bipinnata L and Setara viridis etc is corresoindingly lower than those. There are obvious differences between the rate of heavy metals transport in B. pekinensis and Penoy. The rate of Zn, Hg, Cd is more than 1, and the rate of Zn in Soybean is more than 1, but the transport rate of heavy metals in Oryza sativa is all less than 1.(5) Absorptive amount: Imperata cylindraca var. Major has better effect to absorb Pb, Zn, As, Hg, Cd and Cr. There is preferable ability which makes Setcreasea Pallida to absorb large numbers of Cu, As and Hg. But the absorptive amount of heavy metals in Bidens bipinnata L, Artemisia capillaries and Setara viridis etc is not as large as the others.(6) Typha arientalis Presl are prone to growth in tailing, and imperata cylindraca var. Major, Artemisia capillaries, Bermudagrass, Bidens bipinnata L etc have the ability which tents to root naturally, lives in extreme ecological environments and meliorate soil. But Setara viridis has lower potential of bioremediation. Owning the characteristics of Cu hyperaccumulator, Setcreasea Pallida has preferable ability which makes it can natural root in excessive copper soil.(7) The contaminative status of heavy metal in edible crop are consistent on the whole which are result from Potential Environment Risk Index, Pollution Load Index and Mistiness Mathematics Index, Cd and Pb are the primary contaminative heavy metals, but Cr and Zn engender influence hardly. The contaminative status of heavy metals in Ipomoea aquatica, B. pekinensis, Lactuca sativa and Capsicus frutescens are more serious than in Oryza sativa and Soybean.