摘要
较多的抗生素抗性基因(ARGs)积蓄于剩余污泥中降低了污泥蚯蚓粪的农用价值.为削减污泥蚯蚓粪中的ARGs,向污泥中分别添加1.25%和5%(质量比)的玉米芯生物炭(简称玉米芯炭),以无添加为对照组,揭示玉米芯炭对污泥蚯蚓堆肥过程中微生物种群结构及ARGs的影响.结果表明:添加高含量玉米芯炭显著促进污泥有机质的矿化,提升蚯蚓堆肥产物的电导率和pH值(P<0.05).同时,添加玉米芯炭能增加污泥蚯蚓粪中细菌16S rDNA和真核生物18S rDNA的丰度,且其丰度均与玉米芯炭添加量呈显著正相关性(P<0.05).与对照组相比,高含量玉米芯炭污泥蚯蚓粪中变形菌门、拟杆菌门、放线菌门与浮霉菌门的相对丰度分别降低了11.8%、7.1%、33.3%和20%,但厚壁菌门的丰度显著增加了40%(P<0.05).此外,添加玉米芯炭蚯蚓粪中大环内酯类抗性基因(ermF)和四环素类抗性基因(tetX)的绝对丰度较对照组分别显著降低了32%~45%和13%~31%(P<0.05),但同时整合子基因(intI1)和磺胺类抗性基因(sul2)的丰度分别显著增加了47%~135%和9%~42%(P<0.05).研究结果显示,添加玉米芯炭能增加污泥蚯蚓粪中微生物数量和种群多样性,加速有机质矿化,但对ARGs的削减具有选择性.
The higher content of antibiotics resistance genes(ARGs)accumulated in excess sludge lowers its agricultural value of vermicompost.To eliminate the content of ARGs in sludge vermicompost,this study aimed to reveal the effects of corncob biochars added in sludge on microbial communities and ARGs of vermicomposting.For this,1.25%and 5%of corncob biochars,were separately added to dewatered sludge,comparing with the counterpart without addition of biochars.The addition high content of corncob biochars significantly(P<0.05)promoted the mineralization of organic matter,thus increasing the conductivity and pH of sludge vermicompost.In addition,the corncob biochars(P<0.05)enhanced the gene abundances of bacterial 16S rDNA and eukaryotic 18S rDNA in the vermicompost,resulting in a significantly(P<0.05)positive correlation between the microbial abundance and biochar concentration.Compared to control,the relative abundance of Proteobacteria,Bacteroidetes,Actinomycetes,and Planctomycetes in sludge vermicompost with high content of corncob biochar decreased by 11.8%,7.1%,33.3%and 20%,respectively.However,its abundance of Firmicutes significantly increased by 40%(P<0.05).Besides,the absolute abundance of macrolide resistance genes(ermF)and tetracycline resistance genes(tetX)in vermicompost with corncob biochars significantly decreased by 32%~45%and 13%~31%(P<0.05),respectively.But,the abundance of class 1integron(intI1)and sulfonamides resistance genes(sul2)significantly increased by 47%~135%and 9%~42%(P<0.05)in the final vermciompost,respectively.The addition of corncob biochar in sludge can promote the mineralizaiton of sludge by enhancing microbial number and diversity of microbial,but this addition only selectively reduce the ARGs in vermicompost.
作者
关孟欣
彭兰生
陈景阳
黄魁
夏慧
GUAN Meng-xin;PENG Lan-sheng;CHEN Jing-yang;HUANG Kui;XIA Hui(School of Environmental and Municipal Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Key laboratory of Yellow River Water Environment in Gansu Province,Lanzhou 730070,China;Goldwind Environmental Protection Co.,LTD,Beijing 102600,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2021年第6期2744-2751,共8页
China Environmental Science
基金
国家自然科学基金资助项目(51868036
52000095)
甘肃省高等教师创新能力提升项目(2019A-040)
兰州交通大学百人计划项目。
关键词
生物质炭
蚯蚓堆肥
污泥资源化
抗生素抗性基因
蚯蚓粪有机肥
生物污染物
biochar
vermicomposting
sludge recycling
antibiotics resistance gene
vermicompost fertilizer
biological pollutants
