Characteristics of microbial denitrification under different aeration intensities: Performance, mechanism, and co-occurrence network

Screening of organic substrates for a permeable biobarrier to remediate nitrate contaminated groundwater

“…The time needed for reaching approximately the same removal efficiency was higher for the batch bioreactors than the biobarriers pointing to the importance of microorganism population. As observed for the peanut shell barrier, other bacteria and fungi populations capable in removing nitrate under aerobic conditions were involved (Yao et al, 2020; Yuan et al, 2021). Hu et al (2021) mentioned that different aerobic denitrification strains develop under different C/N ratio and DO concentrations and pointed to the competition between heterotrophs and aerobic denitrifiers.…”

“…The nitrate and TIN removal efficiencies were found to be high under aerobic conditions. Denitrification under aerobic conditions was reported either to occur by bacteria capable to respire both oxygen and nitrate, aerobic denitrifying fungi and/or microanaerobic zones (Bridgham et al, 2013; Yao et al, 2020; Yuan et al, 2021). The relationship between COD and DO concentrations was excellently presented by the correlation coefficient ( r 2 = 0.98).…”

Temporal variation in glacier snowpack bacterial communities mediated by nitrogen

“…The path lengths of the subsurface network were lower than that of the surface layer (Table 2). The shorter path length has been proposed to be associated with a highertransfer efficiencies of information and materials across the microorganisms in the network (Du et al, 2020), which are required for complex biological processes that require extensive microbial collaboration, such as denitrification (Yuan et al, 2021). Thus, the short path length is consistent with the dominance of denitrification processes in the subsurface layer.…”

“…The enhanced biotic associations and cooperation in the subsurface layer may be attributed to the dominance of denitrification processes, as denitrification is a multi-step process that involves multiple microbial cohorts to complete (Henry et al, 2005;Madsen, 2011;Yuan et al, 2021). The enhanced collaboration and deterministic succession had been reported in microbial community associated with the anoxic decomposition of microcystis biomass (Wu et al, 2019), and cross-feeding leads to enhanced positive interactions among the different members of the community (Borchert et al, 2021).…”

“…In comparison, intensive collaboration can enhance complex organic carbon degradation and mineralization, which are particularly important for oligotrophic environments such as glaciers (Bergk Pinto et al, 2019;Krug et al, 2020). Collaboration is also known to be essential to biological processes such as ammonia oxidation and denitrification, in which various organisms carry out different steps of these processes (Henry et al, 2005;Madsen, 2011;Yuan et al, 2021). These changes in interactions and network complexity can favor or disadvantage certain microbial groups, thereby changing the microbial community structure (i.e.…”