水溶性有机物对植物吸收菲的影响及其机制研究

水培小麦试验研究了水溶性有机物(DOM)对植物吸收多环芳烃(菲)的影响,并对其机制进行了初步探讨.结果表明:菲抑制了植物的生长,抑制率达到18.01%,DOM可加剧菲对植物生长的抑制作用,使生长抑制率升至24.38%;植物可吸收和富集水培液中的菲,而DOM能明显地促进植物对菲的吸收和富集作用,使得其根部浓缩系数高达37.63 L·kg^-1,同时DOM还能促进根部吸收的菲向地上部转运;植物在吸收菲的同时,使得营养介质的pH显著升高,DOM与菲存在显著的协同交互作用,可使介质pH值的升高

Impact of Dissolved Organic Matter on Plant Uptake of Phenanthrene and Its Mechanisms

Hydroponic assays were conducted to investigate the influence of dissolved organic matter on uptake of phenanthrene by wheat as well as its mechanisms.The results showed that,under hydroponic condition,phenanthrene impairment of plant growth occurred with wheat growth inhibited rate of 18.01%.The impairment would be greatly enhanced in the presence of dissolved organic matter(DOM) derived from pig manure,and the inhibited rate increased to 24.38%.Wheat could uptake and accumulate phenanthrene in the nutrient solution,which could be escalated by DOM,as indicated by wheat root bioconcentration factor being increased to 37.63 L·kg^-1 in the presence of DOM from 2.84 L·kg^-1 in the absence of DOM.At the same time,DOM could facilitate phenanthrene translocation from plant roots to the upper.As a result,the pH value of nutrient solution could increase by more than 1 unit when the co-existence of DOM and phenanthrene occurred in solution,suggesting that H⁺-phenanthrene cotransport system is involved in the uptake of phenanthrene by plants.A synergism was also found between wheat uptakes of phenanthrene and inorganic nutrients,Moreover,DOM accelerated markedly the synergism.It is concluded that DOM affects the uptake of phenanthrene by plants and the environmental behaviors of phenanthrene.