固氮鱼腥藻介导As(Ⅲ)氧化及其对铵氮输入的响应
Nitrogen-Fixing Anabaena sp.Mediated As(Ⅲ)Oxidation and Its Response to Ammonium Input
钟兆淇 1谢作明 2毛青 1赵欣鑫 1刘太坤1
作者信息
- 1. 中国地质大学环境学院,湖北武汉 430078
- 2. 中国地质大学环境学院,湖北武汉 430078;中国地质大学生物地质与环境地质国家重点实验室,湖北武汉 430078
- 折叠
摘要
铵氮在砷的生物地球化学循环过程中发挥着重要作用,但铵氮输入对藻类介导的As(Ⅲ)生物氧化机理尚不清楚.以固氮蓝藻鱼腥藻(Anabaena sp.)为研究对象,通过室内模拟实验,研究在不同浓度As(Ⅲ)条件下,鱼腥藻对As(Ⅲ)的毒性响应和氧化作用,并研究了外源铵氮输入对鱼腥藻的生长以及氧化As(Ⅲ)的影响.结果表明,鱼腥藻的半抑制浓度(IC50)值为15.59 mg/L,当As(Ⅲ)的浓度为0.1 mg/L、1 mg/L和10 mg/L时,分别在1 d、2 d和7 d内被完全氧化为As(Ⅴ),并且随着As(Ⅲ)浓度增加,鱼腥藻的固氮作用增强.NH4+浓度在234 mg/L以内时,对鱼腥藻(Anabaena sp.)的生长有促进作用,随着NH4+浓度从0 mg/L增加至 1 mg/L、45 mg/L和 234 mg/L,1 mg/L As(Ⅲ)分别在 48 h、36 h、24 h和 12 h被完全氧化.随着NH4+浓度增加,鱼腥藻对砷的吸附量增加,As(Ⅲ)的氧化加速.研究结果有助于阐释天然水体中铵氮在砷生物转化过程中的作用.
Abstract
Ammonium plays an important role in the biogeochemical cycle of arsenic,but the mechanism of ammonium input on algae-mediated As(Ⅲ)bio-oxidation remains unexplored.The arsenic-resistant cyanobacteria Anabaena sp.was used in this study.Through laboratory simulation experiments,the toxicity,oxidation of different As(Ⅲ)concentrations mediated by Anabaena sp.was investigated.The influences of the input of exogenous ammonium on the growth of Anabaena sp.and the oxidation of As(Ⅲ)were also explored.The results show that the IC50 value of Anabaena sp.was 15.59 mg/L,and 0.1 mg/L,1 mg/L and 10 mg/L As(Ⅲ)were completely oxidized to As(Ⅴ)within 1 d,2 d and 7 d,respectively,after inoculating Anabaena sp.,With the concentration of As(Ⅲ)increased,the nitrogen fixation effect of Anabaena sp.is enhanced.Furthermore,the growth of Anabaena sp.was promoted within 234 mg/L NH4+.With the increase of NH4+concentration from 0 mg/L to 1 mg/L,45 mg/L and 234 mg/L,1 mg/L As(Ⅲ)was completely oxidized at 48 h,36 h,24 h and 12 h,respectively,as the concentration of NH4+increases,the adsorption of Anabaena sp.to arsenic increases,and the oxidation of As(Ⅲ)accelerates.The research results help to interpret the role of ammonium nitrogen in the process of arsenic biotransformation in natural waters.
关键词
鱼腥藻/亚砷酸盐/铵氮/毒性/氧化/吸附/地球化学Key words
anabaena sp/arsenite/ammonium/toxicity/oxidation/adsorption/geochemistry引用本文复制引用
基金项目
国家自然科学基金面上项目(41572230)
国家自然科学基金面上项目(41172219)
国家自然科学基金创新研究群体项目(41521001)
出版年
2024
NETL
NSTL
万方数据