摘要
通过盆栽试验研究了重金属铅、镉单一和复合污染及其与常量元素钙、微量元素锌的交互作用对韭菜植株生长发育和Pb、Cd在其根、叶中迁移富集规律的影响。韭菜中Pb、Cd的含量用电感耦合等离子体质谱（ICP-MS）测得。结果表明，韭菜对Pb或Cd的吸收量与土壤单一Pb或Cd污染程度正相关；Pb/Cd之间存在复杂的交互作用，低浓度复合时相互促进吸收，高浓度复合时优先吸收Cd而抑制韭菜对Pb的吸收；锌在高浓度Pb/Cd污染时表现出优良的拮抗作用，可有效降低Pb、Cd的生物有效性并促进韭菜生长。韭菜根是富集Pb、Cd的主要部位，但受代谢方式、迁移率等因素的影响，因而在根、叶中的分布存在差异；根与叶中Cd的浓度比为1.5左右，Pb浓度比主要为2.5~4.5之间，显示Cd更易迁移至韭菜叶组织中。
Ecological effects of heavy metals are often dependent on the presence of other elements. A pot experiment was undertaken to un-derstand the influences of different concentrations of heavy metals（Pb and Cd）and their combinations with Ca, or Zn in soil on growth and Pb and Cd concentrations in the roots and leaves of leeks. Concentrations of Pb or Cd in leeks were positively correlated with those in soils. Lead and Cd had synergism effects at their low concentrations. At high concentrations, however, Pb promoted Cd absorptions, but Cd inhib-ited Pb absorption. Zinc showed excellent antagonistic effects on Pb and Cd under severe pollution by reducing the bio-availability of Pb and Cd, and promoting the growth of leeks. Calcium increased Pb concentrations at low Pb and Cd combined soil, while it inhibited the ab-sorption of Pb at high Pb and Cd combination. Calcium had a very weak inhibitory effect on Cd. Both Pb and Cd were mainly accumulated in roots of leeks. The ratios of Cd in roots to leaves were about 1.5, while those of Pb were 2.5~4.5, indicating easier translocation of Cd than Pb in leeks.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2014年第6期1100-1105,共6页
Journal of Agro-Environment Science
基金
中国地质调查局地质调查工作项目(12120113015200)
国家自然科学基金青年科学基金项目(41201527)
关键词
土壤
铅镉复合污染
韭菜
生长发育
积累特性
soils
lead and cadmium combined pollution
leek
growth
accumulation characteristics
