更新时间:05-12 上传会员:julu1004
分类:环境科学 论文字数:14770 需要金币:1000个
摘要:人类活动对土壤造成的影响越来越严重,特别是土壤重金属污染,铅及其化合物都有毒,会造成土壤污染,是对动植物影响较大的重金属元素之一。本文通过野外调查取样与实验测定相结合的方法,对常州市郊区7个镇蔬菜地土壤及蔬菜的铅污染情况进行了研究,结果表明:不同深度土壤铅的浓度不同,Pb含量随土壤深度的增加而逐渐减少,不同种蔬菜及蔬菜的不同部位铅的富集浓度不同,蔬菜与土壤间铅浓度之间具有一定的相关性。根据国家有关标准,运用单因子污染指数法对土壤表层(0~15cm)和蔬菜可食部位铅污染进行了评价,结果表明:除牛塘和前黄外,其他土样均为轻污染;除萝卜、蒜苗和白菜未受铅污染外,其它蔬菜样品都受到了不同程度的铅污染,部分蔬菜铅超标率较高,超标程度较严重。
关键词:铅污染;单因子污染指数法;土壤;蔬菜地;分布特征
Abstract:The impact of human activities on soil is more and more serious, especially on heavy metal pollution. Lead and its compounds are toxic and will cause soil pollution. It is one of the heavy metal elements which have great impaction on plants and animals. Through combining experimental determination with field survey, this paper studied soils and vegetables in seven towns of the suburbs of Changzhou,the results show that: Lead concentrations in different soil depth is different,and the lead content is gradually reduced with increasing depth of soil; the enrichment of lead concentration is different for different kinds of vegetable and different parts of vegetable. there is a certain correlation between the concentration of lead in vegetables and soil. According to the relevant national standards, lead pollution in surface layer (0 ~ 15cm) of soils and edible parts of vegetables are evaluated by using single-factor pollution index, the results show that: except Niutang and Qianhuang, the other soil samples are light pollution; Except for carrots, garlic and cabbage, the vegetable samples show different levels of lead pollution. Surpassing degrees of some vegetables are large, and over standard rates are high.
Key words: Lead pollution; single factor pollution index; soil; vegetable; distribution characteristics