scholarly journals Widespread detection of human- and ruminant-origin Bacteroidales markers in subtidal waters of the Salish Sea in Washington State

2015 ◽  
Vol 13 (3) ◽  
pp. 827-837 ◽  
Author(s):  
Zack S. Oyafuso ◽  
Anne E. Baxter ◽  
Jason E. Hall ◽  
Sean M. Naman ◽  
Correigh M. Greene ◽  
...  
Keyword(s):  
Transport Mechanism ◽  
Nitrate Concentration ◽  
Impervious Surface ◽  
Washington State ◽  
Marine Water ◽  
Ammonium Concentration ◽  
Mean Flow ◽  
Salish Sea ◽  
Coastal Systems ◽  
Marker Detection

Rising populations around coastal systems are increasing the threats to marine water quality. To assess anthropogenic fecal influence, subtidal waters were examined monthly for human- and ruminant-sourced Bacteroidales markers at 80 sites across six oceanographic basins of the Salish Sea (Washington State) from April through October, 2011. In the basins containing cities with individual populations >190,000, >50% of sites were positive for the human marker, while in the basins with high densities of dairy and cattle operations, ∼30% of sites were positive for the ruminant marker. Marker prevalence was elevated in spring (April and May) and fall (October) and reduced during summer (June through September), corresponding with seasonal precipitation. By logistic regression, the odds of human marker detection increased with percentage of adjacent catchment impervious surface, dissolved nitrate concentration, and abundance of low nucleic acid bacteria, but decreased with salinity and chlorophyll fluorescence. The odds of ruminant marker detection increased with dissolved ammonium concentration, mean flow rate for the nearest river, and adjacent shoreline length. These relationships are consistent with terrestrial to marine water flow as a transport mechanism. Thus, Bacteroidales markers traditionally used for identifying nearby sources can be used for assessing anthropogenic fecal inputs to regional marine ecosystems.

scholarly journals Nitrogen concentrations in a small Mediterranean stream: 1. Nitrate 2. Ammonium

2002 ◽  
Vol 6 (3) ◽  
pp. 539-550 ◽  
Author(s):  
A. Butturini ◽  
F. Sabater
Keyword(s):  
Hyporheic Zone ◽  
Nitrate Concentration ◽  
Stream Water ◽  
Rate Of Change ◽  
Ammonium Concentration ◽  
Precipitation Regime ◽  
Concentration Variance ◽  
N Concentration ◽  
Storm Flow ◽  
Nitrogen Concentrations

Abstract. The importance of storm frequency as well as the groundwater and hyporheic inputs on nitrate (NO3-N) and ammonium (NH4-N) levels in stream water were studied in a small perennial Mediterranean catchment, Riera Major, in northeast Spain. NO3-N concentrations ranged from 0.15 to 1.9 mg l-1. Discharge explained 47% of the annual NO3-N concentration variance, but this percentage increased to 97% when single floods were analysed. The rate of change in nitrate concentration with respect to flow, ΔNO3-N/ΔQ, ranged widely from 0 to 20 μg NO3-N s l-2. The ΔNO3-N/ΔQ values fitted to a non linear model with respect to the storm flow magnitude (ΔQ) (r2=0.48, d.f.=22, P<0.01). High values of ΔNO3-N/ΔQ occurred at intermediate ΔQ values, whereas low ΔNO3-N/ΔQ values occurred during severe storms (ΔQ > 400 l s-1). N3-N concentrations exhibit anticlockwise hysteresis patterns with changing flow and the patterns observed for autumnal and winter storms indicated that groundwater was the main N3-N source for stream and hyporheic water. At baseflow, NO3-N concentration in groundwater was higher (t=4.75, d.f.=29, P>0.001) and co-varied with concentrations in the stream (r=0.91, d.f.=28, P<0.001). In contrast, NO3-N concentration in hyporheic water was identical to that in stream water. The role of the hyporheic zone as source or sink for ammonium was studied hyporheic was studied comparing its concentrations in stream and hyporheic zone before and after a major storm occurred in October 1994 that removed particulate organic matter stored in sediments. Results showed high ammonium concentrations (75±28 s.d. μg NH4-N l-1) before the storm flow in the hyporheic zone. After the storm, the ammonium concentration in the hyporheic dropped by 80% (13.6±8 μg N4-N l-1) and approached to the level found in stream water (11±8 μg NH4-N l-1) indicating that indisturbed hyporheic sediments act as a source for ammonium. After the storm, the ammonium concentrations in the stream, hyporheic and groundwater zones were very similar suggesting that stream ammonium concentrations are sustained mainly by input from groundwater. The present study provides evidence that storm flow magnitude is an important source of variability of nitrate concentration and fluxes in Mediterranean streams subjected to an irregular precipitation regime with prolonged dry periods.

scholarly journals Surveillance for Antibiotic-Resistant E. coli in the Salish Sea Ecosystem

Antibiotics ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1201
Author(s):  
Alexandria Vingino ◽  
Marilyn C. Roberts ◽  
Michelle Wainstein ◽  
James West ◽  
Stephanie A. Norman ◽  
...  
Keyword(s):  
Fresh Water ◽  
Sequence Data ◽  
Puget Sound ◽  
Marine Water ◽  
Lontra Canadensis ◽  
Salish Sea ◽  
Genotypic Resistance ◽  
Antibiotic Resistant ◽  
E Coli ◽  
River Otters

E. coli was isolated from the Salish Sea (Puget Sound) ecosystem, including samples of marine and fresh water, and wildlife dependent on this environment. E. coli isolates were assessed for phenotypic and genotypic resistance to antibiotics. A total of 305 E. coli isolates was characterized from samples collected from: marine water obtained in four quadrants of the Salish Sea; select locations near beaches; fresh water from streams near marine beaches; and fecal samples from harbor porpoises (Phocoena phocoena), harbor seals (Phoca vitulina), river otters (Lontra canadensis), and English sole (Parophrys vetulus). Isolates were evaluated using antimicrobial susceptibility typing, whole-genome sequencing, fumC, and multilocus sequence typing. Resistance and virulence genes were identified from sequence data. Of the 305 isolates from Salish Sea samples, 20 (6.6%) of the E. coli were intermediate, and 31 (10.2%) were resistant to ≥1 class of antibiotics, with 26.9% of nonsusceptible (resistant and intermediate resistant) E. coli isolates from marine mammals and 70% from river otters. The proportion of nonsusceptible isolates from animals was significantly higher than samples taken from marine water (p < 0.0001). A total of 196 unique STs was identified including 37 extraintestinal pathogenic E. coli (ExPEC)-associated STs [ST10, ST38, ST58, ST69, ST73, ST117, ST131, and ST405]. The study suggests that animals may be potential sentinels for antibiotic-resistant and ExPEC E. coli in the Salish Sea ecosystem.

scholarly journals Primary production and associated environmental conditions in the East Siberian Sea in autumn

2019 ◽  
Vol 487 (6) ◽  
pp. 696-700
Author(s):  
A. B. Demidov ◽  
V. I. Gagarin
Keyword(s):  
Spatial Variability ◽  
Primary Production ◽  
Water Column ◽  
Environmental Conditions ◽  
Nitrate Concentration ◽  
Ammonium Concentration ◽  
Photosynthetically Available Radiation ◽  
Dissolved Nitrogen ◽  
East Siberian Sea ◽  
Vast Area

Spatial variability of primary production (PP) was study on vast area of East Siberian Sea in autumn 2017. Water column PP (IPP) value was equal to 28±13 mgC m-2 day-1 on average that testify ultraoligotrophic conditions. IPP was limited by low incident and underwater photosynthetically available radiation and nitrate concentration. Ammonium concentration partly compensates lack of dissolved nitrogen.

Innovative process using Fe0/CO2 for the removal of nitrate from groundwater

2005 ◽  
Vol 5 (5) ◽  
pp. 41-48 ◽  
Author(s):  
C. Ruangchainikom ◽  
C.H. Liao ◽  
J. Anotai ◽  
M.T. Lee
Keyword(s):  
Flow Rate ◽  
Nitrate Concentration ◽  
Air Flow ◽  
Nitrate Removal ◽  
Operation Mode ◽  
Nitrate Solution ◽  
Process Efficiency ◽  
Ammonium Concentration ◽  
Air Flow Rate ◽  
Solution Ph

In this study, the Fe0/CO2 process was investigated for removing nitrate from aqueous solution, in terms of process efficiency, process operation mode, and post-treatment of the end product ammonium. The results show that nitrate at 30 mg/L could be removed from solution within 30 min under the conditions of 2 g/L Fe0 and 200 mL/min CO2 flow rate. Additionally, nitrite was not detected in treated solution, whereas ammonium is the predominant nitrogen-containing species. The normalized residual nitrate concentration decreased with increasing nitrate concentration (2.18–24.19 mg N/L). Nitrate removal was inhibited significantly in the presence of humic acid. Comparing operation modes, NO3− reduction efficiency with increasing number of batch operations in Mode 2 (treated solution was emptied and refilled with freshly prepared solution for the next batch treatment, containing the same level of nitrate as the previous batch) is better than that with Mode 1 (treated solution was retained in the reactor and spiked with concentrated nitrate solution to raise nitrate concentration to a level close to the one in the previous batch). However, to guarantee satisfactory nitrate removal in batch operation mode, zero-valent iron supplementation needs to be taken into consideration. For example, the nitrate removal efficiency without Fe0 supplementation is decreasing in the third batch, compared with those with supplements of 0.25 and 1 g/L. According to a preliminary study, the undesired end-product ammonium can be removed from solution by about 95% within 22.5 h with an air flow rate of 500 mL/min and a solution pH around 12; the ammonium concentration decreased from 6.4 to 0.3 mg 12 N/L. Stripping time can be further shortened by increasing air flow rate and using an efficient air diffuser.

scholarly journals Nitrogen circulation in a Mediterranean holm oak forest, La Castanya, Montseny, northeastern Spain

2002 ◽  
Vol 6 (3) ◽  
pp. 551-558 ◽  
Author(s):  
A. Avila ◽  
A. Rodrigo ◽  
F. Rodà
Keyword(s):  
Hyporheic Zone ◽  
Nitrate Concentration ◽  
Stream Water ◽  
Rate Of Change ◽  
Ammonium Concentration ◽  
Precipitation Regime ◽  
Concentration Variance ◽  
N Concentration ◽  
Storm Flow ◽  
Discharge Regime

Abstract. The importance of storm frequency as well as the groundwater and hyporheic inputs on nitrate (NO3-N) and ammonium (NH4-N) levels in stream water were studied in a small perennial Mediterranean catchment, Riera Major, in northeast Spain. NO3-N concentrations ranged from 0.15 to 1.9 mg l-1. Discharge explained 47% of the annual NO3-N concentration variance, but this percentage increased to 97% when single floods were analysed. The rate of change in nitrate concentration with respect to flow, ΔNO3-N/ΔQ, ranged widely from 0 to 20 μg NO3-N s l-2. The ΔNO3-N/ΔQ values fitted to a non linear model with respect to the storm flow magnitude (ΔQ) (r2=0.48, d.f.=22, P<0.01). High values of ΔNO3-N/ΔQ occurred at intermediate ΔQ values, whereas low ΔNO3-N/ΔQ values occurred during severe storms (ΔQ > 400 l s-1). N3-N concentrations exhibit anticlockwise hysteresis patterns with changing flow and the patterns observed for autumnal and winter storms indicated that groundwater was the main N3-N source for stream and hyporheic water. At baseflow, NO3-N concentration in groundwater was higher (t=4.75, d.f.=29, P>0.001) and co-varied with concentrations in the stream (r=0.91, d.f.=28, P<0.001). In contrast, NO3-N concentration in hyporheic water was identical to that in stream water. The role of the hyporheic zone as source or sink for ammonium was studied hyporheic was studied comparing its concentrations in stream and hyporheic zone before and after a major storm occurred in October 1994 that removed particulate organic matter stored in sediments. Results showed high ammonium concentrations (75±28 s.d. μg NH4-N l-1) before the storm flow in the hyporheic zone. After the storm, the ammonium concentration in the hyporheic dropped by 80% (13.6±8 μg N4-N l-1) and approached to the level found in stream water (11±8 μg NH4-N l-1) indicating that indisturbed hyporheic sediments act as a source for ammonium. After the storm, the ammonium concentrations in the stream, hyporheic and groundwater zones were very similar suggesting that stream ammonium concentrations are sustained mainly by input from groundwater. The present study provides evidence that storm flow magnitude is an important source of variability of nitrate concentration and fluxes in Mediterranean streams subjected to an irregular precipitation regime with prolonged dry periods. Keywords: nitrate, discharge regime, hyporheic zone, groundwater, Mediterranean, stream, Riera Major

A software nitrate sensor based on ammonium and redox signals

2004 ◽  
Vol 48 (11-12) ◽  
pp. 259-265 ◽  
Author(s):  
D. Cecil
Keyword(s):  
Activated Sludge ◽  
Real Time ◽  
Nitrate Concentration ◽  
Systematic Difference ◽  
Denitrification Rate ◽  
Ammonium Concentration ◽  
Nitrification Rate ◽  
Nitrate Sensor

We have computed the nitrate concentration in the activated sludge in real-time using a model, which is a subset of ASM1. The model is in operation at two WWTPs where oxygen, ammonium and redox are measured online in the aeration tanks. The model uses these measurements to continuously adjust its values for the influent ammonium concentration, the nitrification rate, the denitrification rate and the net hydrolysis. Then it computes the nitrate concentration. This value is updated every 10 s. The model results have been compared with the output from a Dr Lange in-situ nitrate sensor at one of these WWTPs. The systematic difference between these two measurements is less than 0.2 mgN l-1 and 90% of the differences are between -1.1 and 1.1 mgN l-1.

The shallow water chiton fauna of the Salish Sea

The Festivus ◽  
2020 ◽  
Vol 52 (4) ◽  
pp. 294-315
Author(s):  
Roger Clark
Keyword(s):  
British Columbia ◽  
Shallow Water ◽  
Washington State ◽  
Inland Waters ◽  
Salish Sea ◽  
The World ◽  
Shallow Subtidal

The Salish Sea, encompassing the inland waters of Washington State, and southern British Columbia, Canada, has one of the richest chiton faunas in the world, with nearly 40 species to be found in the intertidal and shallow subtidal depths, with a few only found on the outer fringe of Salish Sea, not in the inland waters

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