[Objective]The research aimed to explore the ecological effects of uranium-polluted water bodies and the phytoremediation potential of duckweed in response to uranium pollution.[Method]Taking duckweed as the research object,the response mechanism of antioxidant enzyme system and the change of uranium enrichment ability under different uranium stress conditions were studied by applying phosphate.[Result] Duckweed had a relative high uranium enrichment ability,the maximum could reach 44.37 mg/g,and the main effect was adsorption,and the membrane lipid peroxidation stress on plants had less influence.However,after application of phosphate,the uranium enrichment and accumulation coefficient of duckweed in water decreased significantly.The enrichment mechanism may shift from adsorption to absorption,and the bioavailability of uranyl ion had increased,leading to more pronounced membrane lipid peroxidative stress.[Conclusion]Phosphate can significantly reduce the removal of uranium in water by duckweed,but to a certain extent exacerbate the uranium stress on duckweed.%[目的]探讨铀污染水体的生态效应及浮萍应对铀污染的植物修复潜力.[方法]以浮萍为研究对象,通过施加磷酸盐研究其在不同浓度铀胁迫条件下抗氧化酶系统的响应机制以及铀富集能力的变化.[结果]浮萍对水体中的铀有较高的富集能力,最大能达到44.37 mg/g,而且主要是以吸附作用为主,植株受到的膜脂过氧化胁迫程度较小.但在施加磷酸盐后,浮萍对水体中铀的富集能力和富集系数显著下降,富集机制可能由吸附转变为吸收为主,铀酰离子的生物有效性有所提高,从而导致植株受到更为明显的膜脂过氧化胁迫.[结论]磷酸盐的施加可以显著降低浮萍对水体中铀的去除作用,但在一定程度上加剧了浮萍所受到的铀胁迫.
展开▼
