Ma Xingmao, Wang Chen
Department of Civil & Environmental Engineering, Southern Illinois University Carbondale, 1230 Lincoln Drive, Carbondale, IL 62901, USA.
Environ Pollut. 2009 Mar;157(3):1019-23. doi: 10.1016/j.envpol.2008.10.005. Epub 2008 Nov 14.
Sorption to plant roots is the first step for organic contaminants to enter plant tissues. Mounting evidence is showing that sorption to plant roots is nonlinear and competitive. The objective of this study was to investigate the effects of physiochemical properties of homologous chlorinated ethenes and ethanes on the competitive sorption of trichloroethylene (TCE) to the roots of Typha latifolia (cattail). The results showed that chlorinated ethenes exerted significantly stronger competition on the sorption of TCE than chlorinated ethanes. Individual physiochemical properties of organic compounds could be related to the competitive capacity of chlorinated ethenes, but the roles appeared secondary, with molecular structures showing primary effects. Based on these observations, a two-step sorption mechanism was proposed, consisting of the interactions between organic compounds and functional groups on the root surface and subsequent pore filling and absorption to the hydrophobic domains in the composition of roots.
有机污染物进入植物组织的第一步是吸附到植物根系上。越来越多的证据表明，吸附到植物根系上是非线性且具有竞争性的。本研究的目的是调查同源氯代乙烯和氯代乙烷的物理化学性质对三氯乙烯（TCE）在宽叶香蒲（香蒲）根系上竞争性吸附的影响。结果表明，氯代乙烯对TCE吸附的竞争作用比氯代乙烷显著更强。有机化合物的个体物理化学性质可能与氯代乙烯的竞争能力有关，但这些作用似乎是次要的，分子结构显示出主要影响。基于这些观察结果，提出了一种两步吸附机制，包括有机化合物与根表面官能团之间的相互作用以及随后对根组成中疏水区域的孔隙填充和吸收。
