Microbial mechanisms underlying the reduction of NO emissions from submerged plant covered system.

Submerged plant (SP) restoration is a crucial strategy for restoring aquatic ecosystem. However, the effect of SP on nitrous oxide (NO) emissions remains controversial, and the impact of SP-attached biofilms on NO emissions is often overlooked. In this study, SP and non-submerged plant (NSP) systems were set up and operated continuously for 189 days, revealing that SP reduced NO flux by 42.

Evaluating the role of high NO affinity complete denitrifiers and non-denitrifying NO reducing bacteria in reducing NO emissions in river.

Freshwater rivers are hotspots of NO greenhouse gas emissions. Dissolved organic carbon (DOC) is the dominant electron donor for microbial NO reduction, which can reduce NO emission through enriching high NO affinity denitrifiers or enriching non-denitrifying NO-reducing bacteria (NORB), but the primary regulatory pathway remains unclear. Here, field study indicated that high DOC concentration in rivers enhanced denitrification rate but reduced NO flux by improving nosZ gene abundance.

Greenhouse gases emissions from aquaculture ponds: Different emission patterns and key microbial processes affected by increased nitrogen loading.

Global aquaculture production is expected to rise to meet the growing demand for food worldwide, potentially leading to increased anthropogenic greenhouse gases (GHG) emissions. As the demand for fish protein increases, so will stocking density, feeding amounts, and nitrogen loading in aquaculture ponds. However, the impact of GHG emissions and the underlying microbial processes remain poorly understood.

Effect and microbial mechanism of suspended sediments particle size on nitrous oxide emission in eutrophic lakes.

Suspended sediment (SPS) is an important environmental factor in eutrophic lakes, where they may play a significant role in the microbial nitrogen cycle and thus affect the NO source and sink function. This study investigated the correlation and corresponding microbial mechanisms between NO emission fluxes and SPS particle sizes. NO emission characteristics were investigated in four parallel operated lab-scale microcosmic systems, in which different sizes of SPS particles were inoculated (i.

Distinctive Microbial Processes and Controlling Factors Related to Indirect NO Emission from Agricultural and Urban Rivers in Taihu Watershed.

Inland rivers are hotspots of anthropogenic indirect nitrous oxide (NO) emissions, but the underlying microbial processes remain poorly understood. This study measured NO fluxes from agricultural and urban rivers in Taihu watershed and investigated the microbial processes driving NO production and consumption. The NO fluxes were significantly higher in agricultural rivers (140.

Nitrogen removal by heterotrophic nitrifying and aerobic denitrifying bacterium Pseudomonas sp. DM02: Removal performance, mechanism and immobilized application for real aquaculture wastewater treatment.

A bacterial strain was isolated and identified as Pseudomonas sp. DM02 from an aquaculture system. Strain DM02 showed efficient heterotrophic nitrification-aerobic denitrification capability.

Aerobic Denitrification Microbial Community and Function in Zero-Discharge Recirculating Aquaculture System Using a Single Biofloc-Based Suspended Growth Reactor: Influence of the Carbon-to-Nitrogen Ratio.

In this study, the effect of aerobic denitrification on nitrogen removal was investigated using two zero-discharge biofloc-based recirculating aquaculture systems with representative carbon-to-nitrogen (C/N) ratios of 15 (CN15) and 20 (CN20). Aquaculture wastewater, residual feed, and fish feces were treated in an aerated suspended growth reactor (SGR, dissolved oxygen > 5.0 mg L).

Nonlinear response of methane release to increased trophic state levels coupled with microbial processes in shallow lakes.

Shallow lakes are a crucial source of methane (CH), a potent greenhouse gas, to the atmosphere. However, large uncertainties still exist regarding the response of CH emissions to the increasing trophic levels of lakes as well as the underlying mechanisms. Here, we investigate the CH emission flux from lakes with different trophic states in the middle and lower reaches of the Yangtze River basin, China to evaluate the effect of the trophic lake index (TLI) on CH emissions.

Effect evaluation of microplastics on activated sludge nitrification and denitrification.

A large amount of microplastics have entered conventional wastewater treatment plants, and their effects on activated sludge nitrification and denitrification are rarely reported. This study investigated the effects of microplastics on activated sludge nitrification and denitrification using five typical microplastics, namely, polyvinyl chloride (PVC), polypropylene, polyethylene, polystyrene, and polyester (PES) with concentrations of 0, 1000, 5000, and 10,000 particles/L. Results indicated that microplastics had negative effects on ammonia oxidation rate and low effect on nitrite oxidation rate during nitrification.

Suspended particles potentially enhance nitrous oxide (NO) emissions in the oxic estuarine waters of eutrophic lakes: Field and experimental evidence.

Estuaries are considered hot spots for the production and emissions of nitrous oxide (NO) and easily occur suspended particles (SPS), however, current understanding about the role of SPS in the NO emissions from the oxic estuarine waters of lacustrine ecosystems is still limited. In this study, field investigations were performed in the estuaries of hypereutrophic Taihu Lake, and laboratory simulations were simultaneously conducted to ascertain the characteristics of NO emissions with different SPS concentrations. The results showed that the NO emission fluxes ranged from 9.