海口市蔬菜基地土壤和蔬菜中重金属的分布特征及污染评价  

Distribution Characteristics and Evaluation of Heavy Metals in Soils and Vegetables of Vegetable Bases in Haikou City

作　　者：何玉生[1] 廖香俊 倪倩[3] 王丰[1] 傅小丽[1] 

机构地区：[1]海南省地质调查院,海南海口570206 [2]海南省地质局,海南海口570206 [3]中国地质大学(武汉),湖北武汉430074

出　　处：《土壤通报》2015年第3期721-727,共7页Chinese Journal of Soil Science

基　　金：中国地质调查局多目标生态地球化学调查项目(1212010511215)资助

摘　　要：对海口市四大蔬菜基地土壤-蔬菜系统重金属积累及污染状况进行了评价。结果表明,四个蔬菜基地中,新坡基地土壤中Cd、Cr、Zn、As、Ni最高,桂林洋土壤中Cu的含量在各基地中最高,坡博土壤中的Pb和Hg含量最高。叶菜中Pb、Cd、Cr、Ni等元素含量明显高于果菜,说明叶菜较果菜更易吸收和富集重金属。土壤中的Cd全部超过国家土壤环境质量二级标准(GB15612-1995),其中新坡基地土壤Cd污染指数最大。新坡土壤中的Ni超标率为66.7%。各基地土壤中Hg、As、Cr、Ni、Cu、Zn和Pb的含量均未超标,符合蔬菜种植用地要求。单项污染指数的评价结果表明,青菜、油菜、小白菜、大白菜、生菜、芹菜、西红柿均受到Pb轻度污染。综合污染指数结果表明,芹菜重金属轻微超标;青菜、油菜、小白菜、大白菜、生菜、西红柿的重金属污染处于警戒级水平;芥菜、薯叶菜、空心菜、辣椒、苦瓜的重金属属于安全水平。整体来看,叶菜类蔬菜中重金属的污染指数大于果菜类。仅Cr含量在蔬菜与土壤中呈显著负相关关系,说明蔬菜中重金属含量的高低受到除土壤之外的众多因素的影响。This study investigated the concentrations of heavy metals in soils and vegetables in four vegetable bases of Haikou city and evaluated heavy metal pollution of these bases with the methods of single and comprehensive contamination index. The results showed that among four bases, the highest concentrations of Cd, Cr, Zn, As, and Ni were found in soils of Xinpo base, the highest Cu concentrations in Guilinyang base, and the highest concentrations of Pb and Hg in Pobo base. The concentrations of Pb, Cd, Cr, and Ni in leaf vegetable were obviously higher than those in fruit vegetable, indicating that those heavy metals were easier to be accumulated in leaf vegetable. The concentrations of Cd in soils of four vegetable bases exceeded the suggested limits in GB15612-1995, with the highest index of Cd pollution in Xinpo base. Approximately 66.7% Ni in soils of Xinpo base exceeded the limits.Concentrations of other heavy metals including Hg, As, Cr, Ni, Cu, Zn and Pb in soils of all the bases were within safe levels, indicating the soils were suitable for vegetables. The single pollution index indicated that greens, oilseed rape,pakchoi, Chinese cabbage, lettuce, celery and tomato were polluted by Pb slightly. The integrated pollution index indicated slightly pollution in celery, alert levels in greens, oilseed rape, pakchoi, Chinese cabbage, lettuce, and tomato, and safe levels in leaf mustard, potato leaf, swamp cabbage, bell pepper, and bitter gourd. Generally, pollution indices of heavy metals in leaf vegetables were higher than fruit vegetables. Only Cr concentrations in vegetables were negatively correlated with those in soils, indicating many sources of heavy metal(besides soil) in vegetables.

关 键 词：蔬菜 土壤 重金属 污染评价 

分 类 号：X53[环境科学与工程—环境工程] X56X82