Humic Acid Bound Polycyclic Aromatic Hydrocarbons (PAHs) in Rhizosphere of Rice (Oryzae Sativa L.)
To understand the effect of rice root activities on PAHs bound with humic acid in rhizosphere,we conducted a glasshouse study using rhizoboxes to build rhizosphere gradient with one to five millimeter from root surface of rice (Oryzae sativa L.),and measured for polycyclic aromatic hydrocarbons (PAHs) bound with humic acid.The concentration of humic acid bound PAHs were varied with distance from root surface.In soils with high PAHs concentrations,the proportion of humic acid bound PAHs was lower in rhizosphere near root surface,whereas the proportion of humic acid bound PAHs was higher in rhizosphere near root surface in soils with low PAHs concentrations.When evaluating the effect of root on humic acid bound PAHs with toxicity,the concentration of PAHs were transferred into benzoapyrene concentration with equivalency toxicity.Total toxicity of PAHs in rhizosphere decreased with time.The toxicity of humic acid bound PAHs in soils with different spiked concentrations were similar.The toxicity concentration of PAHs bound with humic acid was significantly higher near root surface.The results suggest that rice root activities promoted the bound between PAHs and humic acid in low concentration,but inhibited the bound in high concentration.However,the toxicity of PAHs bound with humic acid was higher near root surface.
Polycyclic aromatic hydrocarbons (PAHs) Humic acid Rhizosphere Rice Toxicity
Bin Ma Jianming Xu
College of Environmental and Natural Resource Sciences,Zhejiang University,Hangzhou 310029,China
国际会议
the 16th Meeting of the International Humic Substances Society (第十六届国际腐殖物质学会大会(IHSS 16))
杭州
英文
318-320
2012-09-09（万方平台首次上网日期，不代表论文的发表时间）