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Showing 1 to 20 of 24 for “"denitrifiers"”.
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Ecology and adaptation of denitrifiers across genomes and environments
… canonical studies typically use model complete denitrifiers capable of fully reducing nitrate to N2 gas, sequencing efforts have revealed a diversity of partial denitrifiers capable of only one or a subset of denitrification steps in natural systems. Much remains to be known about the adaptive …
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Denitrification, Dissimilatory Nitrate Reduction, and Methanogenesis in the Gut of Earthworms (Oligochaeta): Assessment of Greenhouse Gases and Genetic Markers
… as those capable of fermentations, for denitrifiers, and dissimilatory nitrate reducers (DNR). Thus, substrate-derived denitrifiers in the earthworm gut (Lumbricidae) emit the greenhouse gas N2O as well as N2. One large species (Megascolecidae) emitted no N2O, leading to the hypothesis …
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Geomicrobiology of nitrogen in a coastal aquifer : isotopic and molecular methods to examine nitrification and denitrification in groundwater
… to identify the populations of nitrifiers and denitrifiers, where they occur, and what levels of activity are present through the upper four meters of a coastal groundwater system. This work shows two different populations of putative ammonia-oxidizing archaea (AOA) based on the ammonia …
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Geomicrobiology of nitrogen in a coastal aquifer : isotopic and molecular methods to examine nitrification and denitrification in groundwater
… to identify the populations of nitrifiers and denitrifiers, where they occur, and what levels of activity are present through the upper four meters of a coastal groundwater system. This work shows two different populations of putative ammonia-oxidizing archaea (AOA) based on the ammonia …
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Role of microbial diversity in controlling greenhouse gas emissions from conserved forages
… diverse microbial groups such as methanogens and denitrifiers, which are involved in the production and reduction of greenhouse gases (GHGs), i.e., methane (CH₄) and nitrous oxide (N₂O). A laboratory study was conducted to examine the GHG production from alfalfa in the absence of oxygen (O₂). The …
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Greenhouse gas metabolizing prokaryotes in peatlands
… Alpha-, Beta-, and Gammaproteobacterial denitrifiers in all peatlands. Permafrost-affected soils mainly clustered together in the canonical correspondence analysis plots of the analyzed genes. pH was the most important factor determining community composition of nitrate reducers and …
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Investigation of the microbial populations in the activated sludge of the Hoechst-Celanese wastewater treatment plant
… activated sludge were examined. Heterotrophs, denitrifiers, sulfate-reducers, protozoa and filamentous bacteria were enumerated. Variations in microbial populations were compared with influent and effluent constituent concentrations, and with aeration basin characteristics, such as dissolved …
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Characterizing Kinetic Shifts in Nitrifying, Denitrifying, and Phosphorus Removing Biomass Adapting to Low DO
… to characterize oxygen kinetics for nitrifiers, denitrifiers, and PAOs simultaneously is lacking. Here a method was developed to simultaneously measure the oxygen kinetics of nitrifiers, denitrifiers, and PAOs. This method, termed the SND and P-Uptake Oxygen Kinetics test, was able to estimate …
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Microbial nitrogen-cycling and cooperation in the terrestrial subsurface
… the portion of complete versus incomplete denitrifiers was substantially higher under low oxygen conditions. Genes and transcripts encoding atypical Sec-dependant N2O reductases (NosZ) were the most common type, and although usually associated with incomplete denitrifiers, were found here …
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Long term nitrate removal in a denitrification wall
… that C was still sufficiently available to the denitrifiers. These data indicated that the denitrification wall was still effective after 14 years. To predict denitrification wall longevity, a first-order decay curve was fitted to the total C data through time (R2 = 0.92; p < 0.05). The decay …
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Does it pay to be mature? Assessing the performance of a mature bioretention cell seven years post-construction
… Bacterial analysis of the media show most of the denitrifiers are present in the top layers of the bioretention media, despite an internal water storage layer and the bottom of the cell designed specifically for denitrification.
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A preliminary assessment for the use of metabolic inhibitors to evaluate the biodegradation potential of soil
… effect of Na2MoO4 or BESA on the activities of denitrifiers, fermenters, or acetogens.
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Investigation of bacterial populations in a biological nutrient removal system
… to denitrification medium, and MPN's of denitrifiers were recorded. The growth in liquid medium was plated on solid medium. Gram-negative cultures were isolated and identified. The phosphorus-removal capacity of five isolates also was studied. The results indicated that several different …
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The role of dissolved gas fluxes on the biogeochemical evolution of nutrient cycles in lakes.
… Once O2 in the water column is depleted, denitrifiers can use NO3- as their terminal electron acceptor. P, on the other hand, will either bind to metals or be released depending on the surrounding O2 concentrations. The binding of reactive P in oxic conditions can remove it from the water …
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Evaluation of Passive Reduction of Salts and Nutrients from Greenhouse Effluent using Vegetated Bioreactors
… and unplanted units. A greater population of denitrifiers was found in these bioreactors, while the rhizosphere of T. angustifolia displayed the highest microbial activity. The contributions from the plant’s roots as well as the presence of wood-decomposing bacteria such as Bacillus spp. were …
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Microbial Regulation of Soil Greenhouse Gas Emissions in a Non-Bloat Legume Grazing System
… most active nitrifiers following urine addition. Denitrifiers contributed the most N2O in urine amended soils and their dynamics varied. After urine deposition, nirS gene abundance and transcript increases were greater and more sustained than nirK, while nirK increased activity more rapidly but …
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Historical and contemporary drivers of greenhouse gas emissions from upland soils
… caused by stimulation of gross N2O production by denitrifiers. In contrast, depressional soils only had high net N2O emissions between large rain events, and gross N2O production was inhibited following ponding. Greater abundance of Fe reducing microorganisms in depressional soils may facilitate …
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Effects of copper on nitrification and denitrification of leachate from an abandoned landfill
… than were the Nitrobacter species. The denitrifiers appeared to be as sensitive to copper as the Nitrosomonas species.
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The effect of ammonial loading, solids retention time and operating temperature on the biological nitrification and denitrification of high ammonia landfill leachate
… the ammonia oxidizers (Nitrosomonas) or to the denitrifiers, but may have inhibited nitrite oxidizers (Nitrobacter), thereby resulting in nitrite accumulation. When the influent ammonia concentration was raised from 1500 to 2000 mg N/L, nitrification in both systems was observed to decrease from …
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