Study on Enrichment of Heavy Metals by Seven Kinds of Plants in Gejiu Smelting Wastewater Irrigation Area

The contents of heavy metals such as arsenic and cadmium in soil in the milk town of Zhadian,Gejiu City,Yunnan Province was excessive due to the irrigation of smelting wastewater. To study the enrichment features of the heavy metals of the local plants,soils of test plots,seven kinds of native plants (Chenopodium album L.,Raphanus sativus L.,Medicago Sativa L.,Sonchus asper L.,Avena sativa L.,Vicia sativa L. and Brassica napus L.) were selected to examine the accumulations of heavy metal elements (arsenic,cadmium,chromium,and lead) of the plants. The capacity to endure and enrich different heavy metals was analyzed. The results found that the seven kinds of plants could enrich the heavy metals in varying degrees. The cadmium enrichment of radish,huaxiedian sowthistle and rape leaf exceeded 1,which makes them possible become cadmium enrichment plants for phytoremediation of heavy metals. At the same time,because wild peas had powerful biological transfer capacity,wild peas could be used to transfer heavy metal from underground to upper ground to restore heavy metals. Therefore,for this plots of heavy metal contaminated soil,wild peas and huaxiedian sowthistle possessed excellent heavy metal transfer capacity,and could be used as outstanding heavy metal remediation plants