电镀厂尾水重金属对附近水稻田的环境影响

Influence of Heavy Metal from Electroplating Factory Tail Water on Rice Field

采集广西某电镀厂废水处理站尾水塘的底泥和水体样品,并连续两年对河流附近沿岸稻田土壤及水稻进行分析,以确定废水处理站尾水重金属对附近土壤和稻田的环境影响。结果表明,土壤中重金属质量分数与距尾水塘排水口距离无关,主要由河水中重金属浓度决定。使用受污河水灌溉的稻田,受到一定程度的污染,Cu、N i、C r平均质量分数增长率分别为25.69%、22.16%和25.54%,表现出明显的累积效应。重金属在水稻各部位的分布情况为根>茎叶>谷子,表现出出明显的规律性,反映金属离子不易向地上部位迁移的特点。其中根中ωCu≥ωC r>ωN i,茎叶中ωC r≥ωCu>ωN i,谷子中ωCu>ωN i、ωC r>ωN i,表明Cu、C r较易在水稻中富集;谷子中Cu质量分数未超过允许限值,C r超标(最高达45.1倍),但累积效应不明显。

.Near the effluent of an electroplating factory in Guangxi, samples were collected and analyzed in two years. The silt and water samples were from tail water pond, while the soil and rice samples were from a field nearby a river. It was proved that the soil was polluted by heavy metals in a conseqaen of the polluted river. The accumulation effect of the pollution was remarkable. The growth rate of average content for Cu, Ni and Cr was 25. 69%, 22. 16% and 25. 54% respectively. The heavy metal concentration of soil had no relation with the distance of the outlet of tail water pond, it was mainly corresponded by the heavy metal concentration of the river. The distribution of heavy metal in rice tissue was that root^stem leaf^millet and this rule was obviously. The metal ion couldn＇t move easily to upper ground while Cu and Cr accumulated easierly in rice. Tile heavy metal contents of rice tissue was Cu≥Cr〉Ni（in root）, Cr≥Cu〉Ni（in stem leaf） and Cu〉Ni〉.Cr〉Ni（in millet）. The content of Cu in millet was normal and the content of Cr exceeds the standttrd but the accumulation effect was not significantly.