Influence of near-bottom re-suspended sediment on benthic light availability

Troels Møller Pedersen; Charles L. Gallegos; Søren Laurentius Nielsen

doi:10.1016/j.ecss.2012.04.027

Influence of near-bottom re-suspended sediment on benthic light availability

Troels Møller Pedersen, Charles L. Gallegos, Søren Laurentius Nielsen

Environmental Dynamics

Research output: Contribution to journal › Journal article › Research › peer-review

Abstract

Increased light attenuation in the water column is a common consequence of the increased organic loading that accompanies anthropogenic eutrophication in coastal systems. Frequently, the best water quality correlate of the light attenuation coefficient is the total suspended solids, even in systems in which nutrient loading occurs primarily by groundwater input, that is, without strong river inputs of sediment. Alteration of bottomsediment texture, organic content, and bulk density by organic loading has been well documented. Here we report the effect of sedimentre-suspension on near-bottomlight attenuation using an array of in situ light sensors with very close spacing near the sediment–water interface and a radiative transfer (RT) modeling with the software “Hydrolight”. We found that the light attenuation coefficient over 4.5 cm just above the bottom exceeded the attenuation found higher in the water column by a factor ranging from 1.6 to >30. RT modeling indicated that light received at the bottom could be overestimated by a factor 4 or more by extrapolating measurements not taking the near-bottomlight attenuation into account. The results may help explain the wide range of seagrass light requirements observed in different systems.

Original language	English
Journal	Estuarine, Coastal and Shelf Science
Volume	106
Pages (from-to)	93-101
Number of pages	9
ISSN	0272-7714
DOIs	https://doi.org/10.1016/j.ecss.2012.04.027
Publication status	Published - 2012

Keywords

light attenuation
radiative transfer modeling
seagrass distribution
sediment organic content
turbidity

Link to document

10.1016/j.ecss.2012.04.027

REELGRASS: Key parameters and processes affecting the re-establishment of eelgrass in estuaries and coastal waters
Flindt, M. (Project coordinator), Sand-Jensen, K. (Project coordinator), Nielsen, S. L. (Project coordinator), Kristensen, E. (Project coordinator), Borum, J. (Project coordinator), Olesen, B. (Project coordinator), Kock Rasmussen, E. (Project coordinator), Pedersen, M. F. (Project participant), Banta, G. T. (Project participant), Bøgh Pedersen, C. (Project participant), Krause-Jensen, D. (Project participant), Christensen, P. B. (Project participant), Holmer, M. (Project participant), Thamdrup, B. (Project participant), Bundgaard Madsen, H. (Project participant), Holmboe, N. (Project participant), Hjort Jensen, M. (Project participant) & Lumborg, U. (Project participant)
Det Strategiske Forskningsråd, Bæredygtig Energi og Miljø
02/01/2008 → 31/12/2011
Project: Research

Cite this

@article{d9f24acb37c942a6a5000decdfb90d93,

title = "Influence of near-bottom re-suspended sediment on benthic light availability",

abstract = "Increased light attenuation in the water column is a common consequence of the increased organic loading that accompanies anthropogenic eutrophication in coastal systems. Frequently, the best water quality correlate of the light attenuation coefficient is the total suspended solids, even in systems in which nutrient loading occurs primarily by groundwater input, that is, without strong river inputs of sediment. Alteration of bottomsediment texture, organic content, and bulk density by organic loading has been well documented. Here we report the effect of sedimentre-suspension on near-bottomlight attenuation using an array of in situ light sensors with very close spacing near the sediment–water interface and a radiative transfer (RT) modeling with the software “Hydrolight”. We found that the light attenuation coefficient over 4.5 cm just above the bottom exceeded the attenuation found higher in the water column by a factor ranging from 1.6 to >30. RT modeling indicated that light received at the bottom could be overestimated by a factor 4 or more by extrapolating measurements not taking the near-bottomlight attenuation into account. The results may help explain the wide range of seagrass light requirements observed in different systems.",

keywords = "light attenuation, radiative transfer modeling, seagrass distribution, sediment organic content, turbidity",

author = "Pedersen, {Troels M{\o}ller} and Gallegos, {Charles L.} and Nielsen, {S{\o}ren Laurentius}",

year = "2012",

doi = "10.1016/j.ecss.2012.04.027",

language = "English",

volume = "106",

pages = "93--101",

journal = "Estuarine, Coastal and Shelf Science",

issn = "0272-7714",

publisher = "Academic Press",

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TY - JOUR

T1 - Influence of near-bottom re-suspended sediment on benthic light availability

AU - Pedersen, Troels Møller

AU - Gallegos, Charles L.

AU - Nielsen, Søren Laurentius

PY - 2012

Y1 - 2012

N2 - Increased light attenuation in the water column is a common consequence of the increased organic loading that accompanies anthropogenic eutrophication in coastal systems. Frequently, the best water quality correlate of the light attenuation coefficient is the total suspended solids, even in systems in which nutrient loading occurs primarily by groundwater input, that is, without strong river inputs of sediment. Alteration of bottomsediment texture, organic content, and bulk density by organic loading has been well documented. Here we report the effect of sedimentre-suspension on near-bottomlight attenuation using an array of in situ light sensors with very close spacing near the sediment–water interface and a radiative transfer (RT) modeling with the software “Hydrolight”. We found that the light attenuation coefficient over 4.5 cm just above the bottom exceeded the attenuation found higher in the water column by a factor ranging from 1.6 to >30. RT modeling indicated that light received at the bottom could be overestimated by a factor 4 or more by extrapolating measurements not taking the near-bottomlight attenuation into account. The results may help explain the wide range of seagrass light requirements observed in different systems.

AB - Increased light attenuation in the water column is a common consequence of the increased organic loading that accompanies anthropogenic eutrophication in coastal systems. Frequently, the best water quality correlate of the light attenuation coefficient is the total suspended solids, even in systems in which nutrient loading occurs primarily by groundwater input, that is, without strong river inputs of sediment. Alteration of bottomsediment texture, organic content, and bulk density by organic loading has been well documented. Here we report the effect of sedimentre-suspension on near-bottomlight attenuation using an array of in situ light sensors with very close spacing near the sediment–water interface and a radiative transfer (RT) modeling with the software “Hydrolight”. We found that the light attenuation coefficient over 4.5 cm just above the bottom exceeded the attenuation found higher in the water column by a factor ranging from 1.6 to >30. RT modeling indicated that light received at the bottom could be overestimated by a factor 4 or more by extrapolating measurements not taking the near-bottomlight attenuation into account. The results may help explain the wide range of seagrass light requirements observed in different systems.

KW - light attenuation

KW - radiative transfer modeling

KW - seagrass distribution

KW - sediment organic content

KW - turbidity

U2 - 10.1016/j.ecss.2012.04.027

DO - 10.1016/j.ecss.2012.04.027

M3 - Journal article

SN - 0272-7714

VL - 106

SP - 93

EP - 101

JO - Estuarine, Coastal and Shelf Science

JF - Estuarine, Coastal and Shelf Science

ER -

Influence of near-bottom re-suspended sediment on benthic light availability

Abstract

Keywords

Link to document

Projects

REELGRASS: Key parameters and processes affecting the re-establishment of eelgrass in estuaries and coastal waters

Cite this