Pore-water advection and solute fluxes in permeable marine sediments (II): Benthic respiration at three sandy sites with different permeabilities (German Bight, North Sea)

F. Janssen, M. Huettel, Ursula Felicitas Marianne Witte

Research output: Contribution to journalArticle

92 Citations (Scopus)

Abstract

This contribution presents total oxygen uptake (TOU) rates and nutrient fluxes of organically poor permeable shelf sands of the German Bight. Measurements have been made in situ with the novel autonomous benthic chamber system Sandy under controlled conditions of advective pore-water exchange. Average oxygen consumption rates of 31.3 +/- 18.2 mmol m(-2) d(-1) measured in this study were relatively high as compared with rates reported from shelf sediments with much higher organic contents. TOU of highly permeable medium and coarse grained sands was substantially enhanced in the presence of advection. This indicates that advective oxygen supply contributed significantly to respiration in these sediments and that advection has to be considered when assessing oxygen consumption and organic matter mineralization in shelf areas. In fine-grained, less permeable sands, no effect of advection could be measured. A lower advective oxygen supply in these sediments is in agreement with a release of ammonium instead of nitrate and a shallower oxygen penetration depth. Scaled up to the entire German Bight, the results imply that in 40% of the area an effect of advection on benthic oxygen uptake and other advection-related processes can be largely excluded, while in the remaining 60% significant pore-water advection potentially takes place. However, because permeabilities of the sediments investigated in this study were widely spaced, a significant effect on oxygen supply was only verified for highly permeable sands that are likely to cover approximately 3% of the area.

Original languageEnglish
Pages (from-to)779-792
Number of pages13
JournalLimnology and Oceanography
Volume50
Issue number3
Publication statusPublished - May 2005

Keywords

  • CONVECTIVE-TRANSPORT
  • BACTERIAL PRODUCTION
  • INTERTIDAL SANDFLAT
  • COASTAL SEDIMENTS
  • CONTINENTAL-SHELF
  • AQUATIC SEDIMENTS
  • FLOW VELOCITY
  • OXYGEN-UPTAKE
  • WADDEN SEA
  • EXCHANGE

Cite this

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title = "Pore-water advection and solute fluxes in permeable marine sediments (II): Benthic respiration at three sandy sites with different permeabilities (German Bight, North Sea)",
abstract = "This contribution presents total oxygen uptake (TOU) rates and nutrient fluxes of organically poor permeable shelf sands of the German Bight. Measurements have been made in situ with the novel autonomous benthic chamber system Sandy under controlled conditions of advective pore-water exchange. Average oxygen consumption rates of 31.3 +/- 18.2 mmol m(-2) d(-1) measured in this study were relatively high as compared with rates reported from shelf sediments with much higher organic contents. TOU of highly permeable medium and coarse grained sands was substantially enhanced in the presence of advection. This indicates that advective oxygen supply contributed significantly to respiration in these sediments and that advection has to be considered when assessing oxygen consumption and organic matter mineralization in shelf areas. In fine-grained, less permeable sands, no effect of advection could be measured. A lower advective oxygen supply in these sediments is in agreement with a release of ammonium instead of nitrate and a shallower oxygen penetration depth. Scaled up to the entire German Bight, the results imply that in 40{\%} of the area an effect of advection on benthic oxygen uptake and other advection-related processes can be largely excluded, while in the remaining 60{\%} significant pore-water advection potentially takes place. However, because permeabilities of the sediments investigated in this study were widely spaced, a significant effect on oxygen supply was only verified for highly permeable sands that are likely to cover approximately 3{\%} of the area.",
keywords = "CONVECTIVE-TRANSPORT, BACTERIAL PRODUCTION, INTERTIDAL SANDFLAT, COASTAL SEDIMENTS, CONTINENTAL-SHELF, AQUATIC SEDIMENTS, FLOW VELOCITY, OXYGEN-UPTAKE, WADDEN SEA, EXCHANGE",
author = "F. Janssen and M. Huettel and Witte, {Ursula Felicitas Marianne}",
year = "2005",
month = "5",
language = "English",
volume = "50",
pages = "779--792",
journal = "Limnology and Oceanography",
issn = "0024-3590",
publisher = "AMER SOC LIMNOLOGY OCEANOGRAPHY",
number = "3",

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TY - JOUR

T1 - Pore-water advection and solute fluxes in permeable marine sediments (II): Benthic respiration at three sandy sites with different permeabilities (German Bight, North Sea)

AU - Janssen, F.

AU - Huettel, M.

AU - Witte, Ursula Felicitas Marianne

PY - 2005/5

Y1 - 2005/5

N2 - This contribution presents total oxygen uptake (TOU) rates and nutrient fluxes of organically poor permeable shelf sands of the German Bight. Measurements have been made in situ with the novel autonomous benthic chamber system Sandy under controlled conditions of advective pore-water exchange. Average oxygen consumption rates of 31.3 +/- 18.2 mmol m(-2) d(-1) measured in this study were relatively high as compared with rates reported from shelf sediments with much higher organic contents. TOU of highly permeable medium and coarse grained sands was substantially enhanced in the presence of advection. This indicates that advective oxygen supply contributed significantly to respiration in these sediments and that advection has to be considered when assessing oxygen consumption and organic matter mineralization in shelf areas. In fine-grained, less permeable sands, no effect of advection could be measured. A lower advective oxygen supply in these sediments is in agreement with a release of ammonium instead of nitrate and a shallower oxygen penetration depth. Scaled up to the entire German Bight, the results imply that in 40% of the area an effect of advection on benthic oxygen uptake and other advection-related processes can be largely excluded, while in the remaining 60% significant pore-water advection potentially takes place. However, because permeabilities of the sediments investigated in this study were widely spaced, a significant effect on oxygen supply was only verified for highly permeable sands that are likely to cover approximately 3% of the area.

AB - This contribution presents total oxygen uptake (TOU) rates and nutrient fluxes of organically poor permeable shelf sands of the German Bight. Measurements have been made in situ with the novel autonomous benthic chamber system Sandy under controlled conditions of advective pore-water exchange. Average oxygen consumption rates of 31.3 +/- 18.2 mmol m(-2) d(-1) measured in this study were relatively high as compared with rates reported from shelf sediments with much higher organic contents. TOU of highly permeable medium and coarse grained sands was substantially enhanced in the presence of advection. This indicates that advective oxygen supply contributed significantly to respiration in these sediments and that advection has to be considered when assessing oxygen consumption and organic matter mineralization in shelf areas. In fine-grained, less permeable sands, no effect of advection could be measured. A lower advective oxygen supply in these sediments is in agreement with a release of ammonium instead of nitrate and a shallower oxygen penetration depth. Scaled up to the entire German Bight, the results imply that in 40% of the area an effect of advection on benthic oxygen uptake and other advection-related processes can be largely excluded, while in the remaining 60% significant pore-water advection potentially takes place. However, because permeabilities of the sediments investigated in this study were widely spaced, a significant effect on oxygen supply was only verified for highly permeable sands that are likely to cover approximately 3% of the area.

KW - CONVECTIVE-TRANSPORT

KW - BACTERIAL PRODUCTION

KW - INTERTIDAL SANDFLAT

KW - COASTAL SEDIMENTS

KW - CONTINENTAL-SHELF

KW - AQUATIC SEDIMENTS

KW - FLOW VELOCITY

KW - OXYGEN-UPTAKE

KW - WADDEN SEA

KW - EXCHANGE

M3 - Article

VL - 50

SP - 779

EP - 792

JO - Limnology and Oceanography

JF - Limnology and Oceanography

SN - 0024-3590

IS - 3

ER -