UFZ - Helmholtz-Centre for Environmental Research, Department of Environmental Biotechnology, Permoserstr. 15, 04318 Leipzig, Germany; Collaborative Innovation Center for Advanced Nuclear Energy Technology, INET, Tsinghua University, Beijing 100084, PR China.
UFZ - Helmholtz-Centre for Environmental Research, Department of Environmental Biotechnology, Permoserstr. 15, 04318 Leipzig, Germany.
J Hazard Mater. 2021 Apr 15;408:124293. doi: 10.1016/j.jhazmat.2020.124293. Epub 2020 Oct 27.
The herbicide metamitron is frequently detected in the environment, and its degradation in soil differs from that in aquatic sediments. In this study, we applied C-metamitron to investigate the differences in microbial activity, metamitron mineralization and metamitron degrading microbial communities between soil and water-sediment systems. Metamitron increased soil respiration, whereas it suppressed respiration in the water-sediment system as compared to controls. Metamitron was mineralized two-fold faster in soil than in the water-sediment. Incorporation of C from C-metamitron into Phospholipid fatty acids (PLFAs) was higher in soil than in sediment, suggesting higher activity of metamitron-degrading microorganisms in soil. During the accelerated mineralization of metamitron, biomarkers for Gram-negative, Gram-positive bacteria and actinobacteria dominated within the C-PLFAs in soil. Gram-negative bacteria dominated among the metamitron degraders in sediment throughout the incubation period. Actinobacteria, and actinobacteria and fungi were the main consumers of necromass of primary degraders in soil and water-sediment, respectively. This study clearly showed that microbial groups involved in metamitron degradation depend on the system (soil vs. water-sediment) and on time. It also indicated that the turnover of organic chemicals in complex environments is driven by different groups of synthropic degraders (primary degraders and necromass degraders) rather than by a single degrader.
除草剂灭莠猛在环境中经常被检测到，其在土壤中的降解与在水-沉积物中的降解不同。在这项研究中，我们应用 C-灭莠猛来研究土壤和水-沉积物系统中微生物活性、灭莠猛矿化和灭莠猛降解微生物群落的差异。与对照相比，灭莠猛增加了土壤呼吸，但抑制了水-沉积物系统中的呼吸。与水-沉积物相比，灭莠猛在土壤中矿化速度快两倍。从 C-灭莠猛掺入磷脂脂肪酸（PLFA）中的 C 更高，表明土壤中灭莠猛降解微生物的活性更高。在灭莠猛的加速矿化过程中，土壤中 C-PLFA 中的革兰氏阴性菌、革兰氏阳性菌和放线菌生物标志物占主导地位。在整个孵育期间，沉积物中的革兰氏阴性菌一直是灭莠猛降解菌的优势菌群。在土壤和水-沉积物中，放线菌和放线菌与真菌分别是初级降解菌的腐生菌的主要消费者。本研究清楚地表明，参与灭莠猛降解的微生物群取决于系统（土壤与水-沉积物）和时间。它还表明，复杂环境中有机化学品的周转是由不同的协同降解菌（初级降解菌和腐生菌降解菌）而不是单一的降解菌驱动的。
