有机物料水溶性有机物对草萘胺生态毒性影响的研究

Effects of Dissolved Organic Matter on Eco-Toxicity of Napromide in Soil

采用生物培养方法,研究了绿肥、猪粪及污泥中的水溶性有机物(DOM)对土壤中草萘胺生态毒性的影响。结果表明,土壤中草萘胺浓度5～60mg·kg-1与植物种子的发芽指数呈显著负相关性r=-0.9519,与根长抑制率呈显著正相关性r=0.9848;不同来源的DOM均会降低草萘胺的生态毒性,影响程度为猪粪>污泥>绿肥;植物根伸长抑制率与DOM浓度有显著的负相关性r绿肥=-0.9633,r猪粪=-0.8933,r污泥=-0.8509。

Along with application of organic manure, the effects of DOM on th ebehavior of pollutants were paid more attention. To evaluate the effect of DOM on eco-toxicity of Napropamide in soil, biological experiments were performed by using a typical orthic yellow-brown earth soil and three types of DOM, extr acted from a green mamure (GM), pig manure (PM) and sewage sludge (SS).The exper iments were carried at 25 ℃. The results showed that there was a significantly negative relationship between the germination indexes and the concentrations of napropamide(r=-0.951 9, a significantly positive relationship between the inhibition rates of root elongation and that of napropamide (r=0.984 8 ). The results indicated that eco-toxicity of Napropamide was reduced in the presence of three DOM and inhibition degree on plant elongation was PM> SS>G M. DOM affects Napropamide eco-toxicity by complexing hydrophobic component w ith the organic chemicals that enhanced pollutant mobility and reduces its boava ilability. It may be suggested that dissolved organic matter (DOM) reduce adsorp tion of hydrophobic organic pollutants in soils and enhance their mobility by ei ther competing or complexing with organic pollutants molecules in sorption site.