地下水水化学组成对Fe(Ⅱ)氧化过程中锰氧化菌失活的影响  

Effect of Groundwater Hydrochemical Components on the Inactivation of Mn-oxidizing Bacteria upon Fe(Ⅱ) Oxygenation

作　　者：孙群群 屈婧祎 童曼[1] 袁松虎[1] SUN Qunqun;QU Jingyi;TONG Man;YUAN Songhu(State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences(Wuhan),Wuhan 430078,China)

机构地区：[1]中国地质大学(武汉)生物地质与环境地质国家重点实验室,湖北武汉430078

出　　处：《安全与环境工程》2021年第3期101-107,205,F0003,共9页Safety and Environmental Engineering

基　　金：国家自然科学基金青年科学基金项目(41703113);湖北省自然科学基金创新群体项目(2018CFA028)。

摘　　要：溶解态Fe(Ⅱ)和Mn(Ⅱ)常共存于还原性地下水中,受O2扰动Fe(Ⅱ)会快速发生氧化。为了解地下水化学组成对Fe(Ⅱ)氧化过程中锰氧化菌Pseudomonas putida MnB1失活的影响,利用平板计数和邻菲咯啉显色法研究了pH值、天然有机质和阴阳离子对Fe(Ⅱ)氧化过程中MnB1菌株活菌数量和Fe(Ⅱ)浓度变化的影响。结果表明:pH值为7.0的实验体系中MnB1菌株的失活率大于pH值为6.6的实验体系;柠檬酸钠、草酸和腐殖酸均能抑制MnB1菌株的失活,其机制可能为抑制铁(氢)氧化物沉淀的生成,其中草酸和腐殖酸的抑制作用大于柠檬酸钠;PO^(3-)_(4)通过与Fe(Ⅲ)形成不可溶的非晶态铁(氢)氧化物,从而促进MnB1菌株的失活;Mg^(2+)、Ca^(^(2+))的加入可通过降低实验体系的pH值以及共存的Cl^(-)竞争·OH,进而抑制MnB1菌株的失活。该研究结果补充了对地下水中铁锰生物地球化学循环的认识。Dissoloved Fe(Ⅱ)and Mn(Ⅱ)are commonly associated with each other in groundwater.When O2is introduced into the reduced environment,Fe(Ⅱ)will be oxidized immediately.In order to understand the effect of groundwater chemical components on the inactivation of Mn-oxidizing bacteria(Pseudomonas putida MnB1)upon Fe(Ⅱ)oxygenation,this paper evaluates the influence of pH,natural organic matters,cations and anions on the change of MnB1activity and Fe(Ⅱ)concentration upon Fe(Ⅱ)oxygenation by the plate counting method and the 1,10-phenanthroline colorimetric method.The results show that when pH is 7.0,the inactivation rate of MnB1is higher than that when pH is 6.6.Sodium citrate,oxalate acid and humic acid can inhibit the inactivation of MnB1,which could be attributed to the ability of organic matter to prevent the precipitation of iron(hydro)oxides.The inhibition of oxalate acid and humic acid is greater than that of sodium citrate.PO43-may promote MnB1inactivation by producing insoluble iron(hydro)oxides.Mg2+and Ca2+may retard the bactericidal effect by decreasing pH and competition of coexisting Cl-on·OH.The results complement our understanding of the biogeochemical cycle of iron and manganese in groundwater.

关 键 词：地下水 锰氧化菌 Fe(Ⅱ)氧化 活性氧 铁锰循环 

分 类 号：X172[环境科学与工程—环境科学] P593[天文地球—地球化学]