Discontinuation of Glacial Meltwater Input Reshapes the Diversity and Stability of Eukaryotic Planktonic Microbial Communities in Glacial Lakes.

Glacial lakes play a vital role as indicators of global climate change and regional environmental responses. Eukaryotic planktonic microorganisms, pivotal in driving biogeochemical cycling of nutrients within these ecosystems, are crucial for preserving stability and ecological function of glacial lake environments. Nevertheless, the spatial and temporal dynamics, along with the mechanisms responsible for sustaining eukaryotic planktonic microbial communities in glacial lakes, especially during the glacier retreat and lake formation, are still largely uncharted.

Comprehensive analysis of greenhouse gases emissions and microbial dynamics in glacier-fed lakes across various ablation stages.

Glacier melting, a direct consequence of global climate change, significantly influences lake ecosystem structures and greenhouse gases (GHGs) emission in the glacier-fed lake. As glaciers release substantial meltwater containing nitrogen and carbon into lakes, microbial communities and their GHGs emissions could also evolve accordingly. So far, studies on seasonal and diel GHGs emission characteristics and their driving mechanism at high-altitude (> 5000 m) glacier-fed lakes remains relatively constrained.

Characteristics of nutrients and microbial communities in proglacial lakes on the Tibetan Plateau and their potential linkages associated with mercury.

Glacier shrinkages and evolutions of post-glacial ecosystems due to human-induced climate change represent some of the most rapidly occurring ecosystem shifts with potential ecological and societal cascading consequences on Earth. Glacial meltwater could introduce a substantial amount of nutrients, dissolved organic matter (DOM), and contaminants stored in glaciers into the lakes. However, influence of glacial meltwater on microbial communities and its impacts in the transformation of trace contaminants by microbes are frequently underestimated.

Methane cycling in typical emerging proglacial lakes on the Tibetan Plateau: Insights into the metabolic mechanisms mediated by microorganisms.

A large number of high-latitude emerging proglacial lakes have formed on the Tibetan Plateau (TP) due to the global warming and deglaciation. These lakes have the potential to emit methane (CH) because of the exposure of cryopreserved organic carbon, leading to their significance in regional carbon turnover and cycling. However, previous studies have focused more on human-impacted lakes (e.

The superiority of hydrophilic polyurethane in comammox-dominant ammonia oxidation during low-strength wastewater treatment.

Carriers have been extensively employed to enhance nitrification performance during low-strength wastewater treatment by retaining slow-growing ammonia oxidizing microorganisms (AOMs). Still, there is a dearth of systematic understanding of biofilm properties and microbial community structure formed on different carriers. In this study, hydrophilic polyurethane foam (PUF) carriers were prepared and compared with five widely used commercial carriers, namely Kaldness 3, Biochip, activated carbon, volcanic rock, and zeolite.

Ubiquitous occurrence and functional dominance of comammox Nitrospira in full-scale wastewater treatment plants.

The recent discovery of complete ammonia oxidation (comammox) bacteria has fundamentally upended the traditional two-step nitrification conception, but their functional importance in wastewater treatment plants (WWTPs) is still poorly understood. This study investigated distributions of comammox Nitrospira, ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in activated sludge samples collected from 25 full-scale WWTPs. Using quantitative PCR (qPCR) and 16S rRNA gene amplicon sequencing, our results revealed that comammox Nitrospira ubiquitously occurred in all of 25 WWTPs and even outnumbered AOB and AOA with an average abundance of 1∼183 orders of magnitude higher in 19 WWTPs.

Predominance of comammox bacteria among ammonia oxidizers under low dissolved oxygen condition.

Although low-oxygen nitrification can significantly cut down the aeration demand in wastewater treatment plants, little is known about the community dynamics of relevant microorganisms under different oxygen concentrations. Here, by conducting a series of bioreactors with oxygen concentrations of 0%, 2%, 5%, 10%, 20%, 40%, and 70%, we provided a comprehensive investigation on the behaviors and performances of comammox bacteria (CMX), ammonia-oxidizing bacteria (AOB) and archaea (AOA) during the nitrification process. Quantitative PCR analysis demonstrated that CMX was the dominant ammonia-oxidizer under low oxygen condition (10%) after the four-month operation with the abundance increased by 8.