土壤、蔬菜的铅污染相关性分析及土壤铅污染阈限值研究

Relationship between soil Pb pollution and Pb contents in vegetables and pollution threshold of soil Pb

  • 摘要: 为探求土壤重金属污染和蔬菜污染的相关性,为绿色蔬菜生产提供技术支持,以郑州市常见的5种叶菜类蔬菜[油麦菜(Lactuca sativa var.Asparagina)、荆芥(Schizonepeta tenuifolia Briq)、蕹菜(Lpomoea aquelica)、生菜(Lactuca sativa)、苋菜(Amaranthus hypochondriacus)]为试验材料,采用温室盆栽土培的方法研究了土壤Pb浓度与蔬菜污染的相关性,并对绿色蔬菜生产要求的土壤Pb污染阈限值进行了预测。研究结果表明:低浓度Pb污染的土壤对蔬菜生长、产量无明显影响;随着施Pb浓度的增加,5种蔬菜中的Pb含量均呈增加趋势,且与土壤中的Pb含量相关性显著;模拟得出的Pb阈限值油麦菜为39.909 2±2.446 9 mg·kg-1,荆芥43.898 6±3.585 5 mg·kg-1,蕹菜35.293 4±1.787 2 mg·kg-1,生菜33.696 4±2.151 2 mg·kg-1,苋菜34.539 6±2.425 4 mg·kg-1;对Pb富集能力由大到小排序为生菜>苋菜>蕹菜>油麦菜>荆芥。

     

    Abstract: In order to determine the impact of soil heavy metal pollution on vegetable and to enhance quality of green vegetable production, the relationship between soil Pb content and Pb pollution of vegetables was studied under greenhouse conditions using five commonly cultivated foliage vegetables (Lactuca sativa var. Asparagina, Schizonepeta tenuifolia Briq, Lpomoea aquelica, Lactuca sativa, Amaranthus hypochondriacus) in Zhengzhou, Henan Province. Soil Pb pollution threshold for the production of green vegetables was analyzed as well. The results show that low Pb polluted soils have insignificant effect on vegetable growth and output. Pb content in the 5 vegetables increases with increasing density of soil Pb, and no consistent pattern of relationship exists between Pb content in the soil and vegetables. Simulated Pb threshold limit is: L. sativa var. Asparagina 39.909 2 ±2.446 9 mg·kg-1, S. tenuifolia 43.898 6±3.585 5 mg·kg-1, L. aquelica 35.293 4±1.787 2 mg·kg-1,L. sativa 33.696 4±2.151 2 mg·kg-1,A. hypochondriacus 34.539 6±2.425 4 mg·kg-1. Pb concentration (ranked from highest to lowest) is as follows: L. sativa>A. hypochondriacusL. aquelicaL. sativa var. AsparaginaS. tenuifolia.