Quantitative estimates of denitrification are needed in designing artificial wetlands to optimize nitrate (NOj-) removal. Acetylene blockage and ~SN-tracer methods were employed to quantify denitriflcation in constructed wetlands receiving agricultural tile drainage, using plastic tubes to enclose in situ mesocosms. Estimates were also made through NO;disappearance from mesocosm water columns. ...

Several groundwater vulnerability methodologies have been implemented throughout the years to face increasing worldwide pollution, ranging from simple rating complex numerical, statistical, and hybrid methods. Most of these methods used evaluate nitrate, which is considered major contaminant worldwide. Together with dilution, degradation nitrate via denitrification has acknowledged as a process...

Environmental conditions can change dramatically over a crop season and among locations in an agricultural field and can increase denitrification and emissions of the potent greenhouse gas nitrous oxide. In a previous study, changes in the overall size of the denitrifier community in a potato crop field were relatively small and did not correlate with variations in environmental conditions or d...

sulfur utilizing autotrophic denitrification synthetic wastewater in up flow packed --bed reactor was evaluated under different concentrations of alkalinity and organic matter. the reactor was filled with granular elemental sulfur particles with diameters of 2.8-5.6 mm and porosity of 40%. the initial culture was prepared from sludge of shahrak ghods wastewater treatment plant. first, the stoic...

Carbon sources such as methanol and glycerol are used for enhancing denitrification at wastewater treatment plants, which are required to meet increasingly stringent effluent nitrogen limits. Consequently, dosing strategies for these compounds could benefit from the development and application of molecular activity biomarkers to infer and distinguish between methanol- or glycerol-based denitrif...

The objective of this research was to interrogate and develop a better understanding for a process to achieve post-anoxic denitrification without exogenous carbon augmentation within enhanced biological phosphorus removal (EBPR). Sequencing batch reactors fed real wastewater and seeded with mixed microbial consortia were operated under variable anaerobic-aerobic-anoxic and organic carbon loadin...

Urine excreted by cattle can produce very high concentrations of available N in relatively small volumes of soil and lead to high nitrous oxide (N2O) emissions. Application of the nitrification inhibitor dicyandiamide (DCD) can inhibit nitrification. DCD application results in lower nitrate (NO3 ) concentrations and N2O emissions from denitrification in urine affected soils. However, the effect...

A laboratory study using a combined upflow anaerobic sludge bed (UASB)-activated sludge (AS) reactor system was undertaken to explore the effect of recycle-to-influent ratio (R(e)=1, 2, and 3) on the activities of nitrifiers and denitrifiers. Suspended-solids pre-settled piggery wastewater was used as the substrate-feed wastewater. At the R(e) of 1-3, the combined reactor system achieved effici...

Denitrification is a critical process regulating the removal of bioavailable nitrogen (N) from natural and human-altered systems. While it has been extensively studied in terrestrial, freshwater, and marine systems, there has been limited communication among denitrification scientists working in these individual systems. Here, we compare rates of denitrification and controlling factors across a...