摘要
本文通过对镉、铅、砷处理土壤中黄瓜和玉米的伤流、外渗液、土壤及作物中的含量分析,研究了农作物对镉、铅、砷的吸收特征。结果表明:3种元素均存在通过共质体进入导管并向上运输的途径,镉、铅、砷在土壤-植物系统中的活性有明显差异,其中Cd>Pb,As的活性及毒性均较强。As明显抑制根系的活性,降低了伤流和蒸腾速率。本试验条件下Cd、Pb、As对根系透性均无显著影响,但外渗率却有As>Cd>Pb的结果。此外,3种元素对其它营养元素从根中的外渗也有不同程度的影响。
Pb, Cd and As were analysed for cucumber and maize crops and their bleeding saps and root effluxes. All the three elements can go into the vascular through the 'syrmplast' pathway and transfer up to the shoots in the air. Their activities in soil—plant system vary significantly. Arsenic causes growth retardation of the roots, decreases the rates of sap bleeding and transpiration. In these experiments, Cd, Pb and As do not cause significant changes of permeability of root memberanes. The sequence of leachage rates of them is As>Cd>Pb. The leachage rates of certain nu trient elements are influenced to various extent by the three elements.
出处
《农业环境保护》
CSCD
1992年第4期171-175,共5页
Agro-Environmental Protection
基金
自然科学基金
