Coupling of bacterial nitrification with denitrification and anammox supports N removal in intertidal sediments (Arcachon Bay, France)

Abstract. Tidal estuarine channels have complex and dynamic interfaces controlled by upland groundwater discharge, waves, tides and channel velocities that also control biogeochemical processes within adjacent sediments. In an Australian subtropical estuary, discharging groundwater with elevated (> 300 mg N L−1) NH4+ and NO3- concentrations had 80 % of the N attenuated at this interface, one of the highest N removal rates (> 100 mmol m−2 day−1) measured for intertidal sediments. The remaining N was also diluted by a factor of 2 or more by mixing with surface water before being discharged to the estuary. Most of the mixing occurred in a hyporheic zone in the upper 50 cm of the channel bed. However, groundwater entering this zone was already partially mixed (12 %–60 %) with surface water via tide-induced circulation. Below the hyporheic zone (50–125 cm below the channel bed), NO3- concentrations declined slightly faster than NH4+ concentrations and δ15NNO3 and δ18ONO3 gradually increased, suggesting a co-occurrence of anammox and denitrification. In the hyporheic zone, δ15NNO3 continued to become enriched (consistent with either denitrification or anammox) but δ18ONO3 became more depleted (indicating some nitrification). A high δ15NNO3 (23 ‰–35 ‰) and a low δ18ONO3 (1.2 ‰–8.2 ‰) in all porewater samples indicated that the original synthetic nitrate pool (industrial NH4NO3; δ15N ∼ 0 ‰; δ18O ∼ 18 ‰–20 ‰) had turned over completely during transport in the aquifer before reaching the channel bed. Whilst porewater NO3- was more δ18O depleted than its synthetic source, porewater δ18OH2O (−3.2 ‰ to −1.8 ‰) was enriched by 1 ‰–4 ‰ relative to rainfall-derived groundwater mixed with seawater. Isotopic fractionation from H2O uptake during the N cycle and H2O production during synthetic NO3- reduction are the probable causes for this δ18OH2O enrichment. Whilst occurring at a smaller spatial scale than tide-induced circulation, hyporheic exchange can provide a similar magnitude of mixing and biogeochemical transformations for groundwater solutes discharging through intertidal zones.

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Effects of age class on N removal capacity of oysters and implications for bioremediation

Marine Ecology Progress Series ◽

10.3354/meps11252 ◽

2015 ◽

Vol 528 ◽

pp. 205-220 ◽

Cited By ~ 8

Author(s):

DJ Dalrymple ◽

RH Carmichael

Keyword(s):

Age Class ◽

Removal Capacity ◽

N Removal

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Draft genome of starch-degrading actinobacterium, Microbacterium mangrovi MUSC 115T isolated from intertidal sediments

Progress in Drug Discovery & Biomedical Science ◽

10.36877/pddbs.a0000005 ◽

2018 ◽

Vol 1 (1) ◽

Author(s):

Hooi-Leng Ser ◽

Wen-Si Tan ◽

Huey-Jia Cheng ◽

Wai-Fong Yin ◽

Kok-Gan Chan ◽

...

Keyword(s):

Draft Genome ◽

Intertidal Sediments ◽

Total Size ◽

General Physiology ◽

Genome Features

Microbacterium mangrovi strain MUSC 115T was isolated from intertidal sediments of Kuantan, Malaysia. Here we describe the draft genome of amylolytic strain MUSC 115T with total size of 4.4 Mbp from 55 contigs and G + C content of 70.0%. Total of 4,096 coding genes were observed, with 2 putative amylases genes in the draft genome of MUSC 115T. These genome features of MUSC 115T can improve our understanding of its starch-degrading mechanism and general physiology of the species, which provide opportunities for biotechnological and industrial exploitation.

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Impact of Nitrogen Management Practices on Total Nitrogen in the Fruits of High Productive Hamlin Orange Trees

HortScience ◽

10.21273/hortsci.33.3.498e ◽

1998 ◽

Vol 33 (3) ◽

pp. 498e-498

Author(s):

S. Paramasivam ◽

A.K. Alva

Keyword(s):

Crop Production ◽

Management Practices ◽

Fine Sand ◽

Fruit Production ◽

Perennial Crop ◽

Total N ◽

N Removal ◽

Leaf N Concentration ◽

N Rates ◽

Orange Trees

For perennial crop production conditions, major portion of nutrient removal from the soil-tree system is that in harvested fruits. Nitrogen in the fruits was calculated for 22-year-old `Hamlin' orange (Citrus sinensis) trees on Cleopatra mandarin (Citrus reticulata) rootstock, grown in a Tavares fine sand (hyperthermic, uncoated, Typic Quartzipsamments) that received various N rates (112, 168, 224, and 280 kg N/ha per year) as either i) broadcast of dry granular form (DGF; four applications/year), or ii) fertigation (FRT; 15 applications/year). Total N in the fruits (mean across 4 years) varied from 82 to 110 and 89 to 111 kg N/ha per year for the DGF and FRT sources, respectively. Proportion of N in the fruits in relation to N applied decreased from 74% to 39% for the DGF and from 80% to 40% for the FRT treatments. High percentage of N removal in the fruits in relation to total N applied at low N rates indicate that trees may be depleting the tree reserve for maintaining fruit production. This was evident, to some extent, by the low leaf N concentration at the low N treatments. Furthermore, canopy density was also lower in the low N trees compared to those that received higher N rates.

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The Use of Anoxic Selectors for the Control of Low F/M Activated Sludge Bulking

Water Science & Technology ◽

10.2166/wst.1989.0263 ◽

1989 ◽

Vol 21 (6-7) ◽

pp. 609-619 ◽

Cited By ~ 13

Author(s):

Y.-J. Shao ◽

David Jenkins

Keyword(s):

Organic Matter ◽

Activated Sludge ◽

Pilot Plant ◽

Detention Time ◽

Substrate Removal ◽

Batch System ◽

Sludge Bulking ◽

N Removal ◽

Soluble Substrate ◽

Activated Sludge Systems

Laboratory and pilot plant experiments on anoxic selector activated sludge systems were conducted on two wastewaters in some cases supplemented with nitrate, acetate or glucose. To prevent bulking sufficient anoxic selector detention time and nitrate levels must be available to reduce selector effluent soluble COD to below 100 mg/l and to reduce readily metabolizable organic matter to virtually zero (< 1 mg/l). Soluble COD/NO3-N removal stoichiometry is in the range 6.0-6.7. Selector systems have elevated soluble substrate removal and denitrification rates compared to CSTR systems. These rates are not affected greatly by temperature (20-25°C) for CSTR sludges but are for selector sludges. Upon exhaustion of nitrate in a selector soluble COD leaks out of the activated sludge in significant amounts. Thiothrix sp. and type 021N denitrify only to NO2 and at much slower rates than Zoogloearamigera does to N2. A sequencing batch system provides an optimistic estimate of the SVI that can be obtained by an anoxic selector system.

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Upgrading to nutrient removal by means of internal carbon from sludge hydrolysis

Water Science & Technology ◽

10.2166/wst.1994.0576 ◽

1994 ◽

Vol 29 (12) ◽

pp. 31-40 ◽

Cited By ~ 13

Author(s):

Pia Prohaska Brinch ◽

Kim Rindel ◽

Kathryn Kalb

Keyword(s):

Reaction Rate ◽

Wastewater Treatment Plants ◽

Secondary Treatment ◽

N Removal ◽

Sludge Hydrolysis ◽

Speed Up ◽

On Line ◽

Full Scale Tests ◽

Biological Phosphorus ◽

Hydrolysis Of

Due to the introduction of stricter nutrient effluent standards, many existing wastewater treatment plants performing only primary or secondary treatment are about to be upgraded. As the space available at the plants is, however, often limited, processes are required which will accommodate the need for increased treatment capacity without requiring much more space. In the hydrolysis of primary or pre-precipitated sludge direct-degradable organic carbon is produced which can speed up the reaction rate and increase both biological phosphorus and nitrogen removal. Full-scale tests with dosing of hydrolysate for biological P and N removal, respectively, have shown that this is a most viable process. The use of on-line monitoring has improved the process further.

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Denitrification in a Carbon and Nitrogen Removal System for Leachate Treatment: Performance of a Upflow Sludge Blanket (USB) Reactor

Water Science & Technology ◽

10.2166/wst.1999.0407 ◽

1999 ◽

Vol 40 (8) ◽

pp. 145-151 ◽

Cited By ~ 11

Author(s):

Liliana Borzacconi ◽

Gisela Ottonello ◽

Elena Castelló ◽

Heber Pelaez ◽

Augusto Gazzola ◽

...

Keyword(s):

Complete System ◽

Carbon Sources ◽

Uasb Reactor ◽

Leachate Treatment ◽

N Removal ◽

Start Up ◽

Aerobic Reactor ◽

C And N ◽

Reactor Operating ◽

Removal System

The performance of a bench scale upflow sludge bed (USB) denitrifying reactor was evaluated in order to integrate it into a C and N removal system for Sanitary Landfill Leachate. The raw leachate used presented COD and NH4-N average values of 30000 mg/l and 1000 mg/l, respectively. The complete system comprises in addition an UASB reactor and a nitrifying RBC. A portion of the aerobic reactor effluent was recycled into the denitrification stage and some raw leachate was also added as an additional C source. In order to obtain operating parameters the denitrifying reactor was operated alone. Sludge from an aerobic reactor (RBC) treating raw leachate was used as inoculum. Shortly after the start up, good granulation of the sludge bed was observed. Using raw leachate and UASB outlet as carbon sources with COD/NO3-N ratios of 4 and 12, respectively, denitrification efficiencies of about 90% were reached. A sludge yield of 0.16 gVSS/gCODremoved was obtained operating with raw leachate. For the anoxic reactor operating in the complete system, denitrification efficiencies of 90% were also achieved. A nitrogen gas recycle was a successful way to avoid frequently observed sludge bed rising problems.

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Agricultural practices and diffuse nitrogen pollution in Denmark: empirical leaching and catchment models

Water Science & Technology ◽

10.2166/wst.1999.0554 ◽

1999 ◽

Vol 39 (12) ◽

pp. 257-264 ◽

Cited By ~ 5

Author(s):

Hans E. Andersen ◽

Brian Kronvang ◽

Søren E. Larsen

Keyword(s):

Agricultural Land ◽

Root Zone ◽

Agricultural Practices ◽

Animal Manure ◽

Annual Runoff ◽

N Leaching ◽

N Loss ◽

Total N ◽

Model Calculations ◽

N Removal

An empirical leaching model was applied to data on agricultural practices at the field level within 6 small Danish agricultural catchments in order to document any changes in nitrogen (N) leaching from the root zone during the period 1989-96. The model calculations performed at normal climate revealed an average reduction in N-leaching that amounted to 30% in the loamy catchments and 9% in the sandy catchments. The reductions in N leaching could be ascribed to several improvements in agricultural practices during the study period: (i) regulations on livestock density; (ii) regulations on the utilisation of animal manure; (iii) regulations concerning application practices for manure. The average annual total N-loss from agricultural areas to surface water constituted only 54% of the annual average N leached from the root zone in the three loamy catchments and 17% in the three sandy catchments. Thus, subsurface N-removal processes are capable of removing large amounts of N leached from agricultural land. An empirical model for the annual diffuse N-loss to streams from small catchments is presented. The model predicts annual N-loss as a function of the average annual use of mineral fertiliser and manure in the catchment and the total annual runoff from the unsaturated zone.

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