Comparison of two automated ammonium methods in a region of coastal upwelling

Slawyk, Gerd; MacIsaac, J.J.

doi:10.1016/0011-7471(72)90019-8

Cited by 115 publications

(70 citation statements)

References 6 publications

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“…Samples were gently filtered into acid-washed polyethylene bottles and were analyzed immediately for dissolved inorganic nitrogen (DIN) as ammonium (NH:) and nitrate (NO, + NO;) and for urea concentrations. Alternatively, filtered samples were stored frozen (-20 "C) and analyzed within 24 h. NH: and NO, + NO; were measured with a Technicon Autoanalyzer@ I1 following the procedures outlined in Slawyk & MacIsaac (1972) and Wood et al (1967), respectively. Urea was determined by the diacetyl monoxime thiosemicarbizide technique described by Price & Harrison (unpubl.).…”

Section: Methodsmentioning

confidence: 99%

Time course of uptake of inorganic and organic nitrogen by phytoplankton in the Strait of Georgia: comparison of frontal and stratified communities

Price¹,

Cochlan²,

Harrison³

1985

Mar. Ecol. Prog. Ser.

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In both frontal and stratified water of the Strait of Georgia, changes in dissolved nitrogen concentrations provided evidence for the simultaneous uptake of ammonium, nitrate and urea by a summer phytoplankton community. Chlorophyll a specific uptake rates of ammonium and urea were ca 2 and 2.4 times greater in stratified water than in frontal water, whereas chlorophyll a specific nitrate uptake rates were ca 1.6 times greater in frontal water. Ammonium and urea regeneration rates, calculated using a mass balance approach, were similar in frontal water, but urea regeneration rates were 2 to 5 times greater in the stratified water during the first 12 h of the experiment. Increases in particulate nitrogen could not be accounted for by corresponding decreases in total concentration of dissolved inorganic nitrogen and urea, or by 15N accumulation in the particulates. In frontal water the change in total dissolved inorganic nitrogen and urea consistently overestimated the change in particulate nitrogen, and in stratified water the change in total dissolved inorganic nitrogen and urea consistently underestimated the change in particulate nitrogen. These data suggest that the plankton community In frontal water was losing nitrogen in the form of dissolved organic nitrogen. By contrast, the plankton community in stratified water took up nitrogen compounds which were not measured as part of the total dissolved inorganic and urea nitrogen, but were most likely dissolved organic nitrogen compounds. Results stress the importance of determining uptake rates of all 3 nitrogen substrates (NHfi, N O and urea) using 15N isotopes and by simultaneously measuring the change in concentration of these compounds throughout the incubation period.

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Section: Methodsmentioning

confidence: 99%

Time course of uptake of inorganic and organic nitrogen by phytoplankton in the Strait of Georgia: comparison of frontal and stratified communities

Price¹,

Cochlan²,

Harrison³

1985

Mar. Ecol. Prog. Ser.

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“…Ammonium, nitrite and nitrate concentrations were determined using an automatic analyzer (Quaatro, Bran & Luebbe) based on colorimetric techniques. The indophenol blue method was used to measure the ammonium concentration according to (Slawyk and MacIssac, 1972). Nitrate was determined after cadmium reduction to nitrite.…”

Section: Chemical Analysismentioning

confidence: 99%

The response of river nitrification to changes in wastewater treatment (The case of the lower Seine River downstream from Paris)

Aissa-Grouz

Garnier

Billen

et al. 2015

Ann. Limnol. - Int. J. Lim.

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-In the early 2000s, most of the effluents from the Paris agglomeration (12 million inhabitants) were still discharged after only a standard activated sludge treatment of carbon, thus releasing a high ammonium load. This triggered the growth of nitrifying bacteria in the river and caused a deficit of dissolved oxygen concentration 200 km downstream, at the entrance of the estuarine area. From 2007 on, improvements of the wastewater treatment plant (WWTP) helped to nitrify most of the ammonium, and to denitrify 70% of the nitrate produced since 2012. This paper documents the effect of these recent changes in the treatment of Paris effluents, based on measurements of nitrogen species concentrations and nitrifying activities along longitudinal profiles of the lower Seine River. These observations are put into perspective with respect to previous observations, and a modeling approach is developed to evidence the role of ammonium and nitrifying organisms released with the WWTP effluents into the receiving water body. Today, a larger biomass of ammoniumoxidizing microbes is being discharged by the WWTP, but the microorganisms released do not grow, possibly because of the low substrate in the river. The same is true for nitrite-oxidizing microbes, which explains the persistence of nitrite often discharged with the effluents because of incomplete nitrification and/or denitrification in the treatment line. Taking into account the development of microbial populations of nitrifying organisms is essential to explain the observed spatial and temporal pattern of the nitrogen species.

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“…Luebbe) flow-through spectrophotometric apparatus using standard procedures (Jones 1984;Slawyck and McIsaac 1972): ammonium reacted with salicylate and dichloro-isocyanuric acid, using nitroprusside as a catalyst, to produce a blue compound measured at 660 nm; nitrite reacted under acidic conditions with sulfanilamide to form a diazo-compound that then couples with N-(1-naphtyl)-ethylenediamine to form a reddish-purple azo-dye that is measured at 550 nm; nitrate was determined after reduction into nitrite. Ortho-phosphate from filtered water samples was reacted with molybdate and ascorbic acid in the presence of antimony potassium tartrate to form a blue compound measured at 880 nm; total P was determined on unfiltered water after sodium persulfate digestion and mineralization at 110°C in an acidic phase (Eberlein and Katter 1984).…”

Section: Dissolved Elementsmentioning

confidence: 99%

N, P, Si budgets for the Red River Delta (northern Vietnam): how the delta affects river nutrient delivery to the sea

et al. 2010

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The Red River Delta (RRD) (Vietnam), a region experiencing rapid population growth, industrialization, and economic development, concentrates 54% of the population of the whole Red River watershed in less than 10% of the basin area. Our study aimed at understanding and quantifying the processes by which the delta affects the nutrient fluxes coming from the upstream watershed before they reach the sea. A comprehensive budget of nitrogen (N), phosphorus (P), and silica (Si) fluxes associated with natural and anthropogenic processes in the terrestrial and hydrological system of the delta was established for five sub-basins of the delta for the period 2000-2006, based on official statistical data, available measurements, and our own sampling campaigns and enquiries. The results show that anthropogenic inputs of N and P brought into the delta area are higher than the amounts delivered by the river from the upstream watershed. However, the amounts of these two elements ultimately delivered to the coastal zone from the delta are lower than the amounts carried by the upstream river, showing extremely efficient retention of both the soils and the delta's drainage network. For Si (taking into account both dissolved and amorphous solid forms), the retention is much lower. High retention of N and P and low retention of Si in the delta area have up to now protected the coastal zone from severe eutrophication problems.Electronic supplementary material The online version of this article

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Comparison of two automated ammonium methods in a region of coastal upwelling

Cited by 115 publications

References 6 publications

Time course of uptake of inorganic and organic nitrogen by phytoplankton in the Strait of Georgia: comparison of frontal and stratified communities

Time course of uptake of inorganic and organic nitrogen by phytoplankton in the Strait of Georgia: comparison of frontal and stratified communities

The response of river nitrification to changes in wastewater treatment (The case of the lower Seine River downstream from Paris)

N, P, Si budgets for the Red River Delta (northern Vietnam): how the delta affects river nutrient delivery to the sea

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