Response of an abyssal macrofaunal community to a phytodetrital pulse

Andrew K. Sweetman, Ursula Witte

Research output: Contribution to journalArticle

Abstract

The majority of deep-sea benthic communities rely on particulate organic matter (POM) sinking from the euphotic zone for energy, much of which is delivered in pulsed events. But we know little about abyssal plain macrofaunal communities, their response to such events or their role in deep-sea carbon-cycling. In this study, we examined the composition of the macrofaunal community at Station M in the deep NE Pacific and assessed its short-term response to a simulated OM pulse in two 36 h in situ enrichment experiments. In each experiment, 1.2 gC m–2 of 13C-labelled Skeletonema costatum was deposited onto the seafloor using a benthic chamber lander. Macrofaunal abundance and biomass were significantly higher at 0 to 5 cm depth compared to 5 to 10 cm, and were dominated by the Nematoda and Crustacea, respectively. Twenty-five percent of the macrofauna specimens showed 13C signatures indicative of label ingestion, but specific uptake (Δδ13C) and C-turnover rates varied strongly between and within taxa. Two organisms, a single cumacean from 1 chamber and a paraonid polychaete from the second chamber, were responsible for the majority of C-uptake and had ingested up to 2.3% of their body weight in C. Macrofaunal C-turnover was much lower than recorded in the abyssal NE Atlantic, which is most likely due to differences in the timing of the experiments relative to the spring/summer bloom, different experimental durations and disparities in macrofaunal community structure. These results emphasize the degree of plasticity inherent in the macrofaunal response to a food pulse and stress the need for comprehensive in situ investigations to further our understanding of deep-sea benthic ecosystem functioning.
Original languageEnglish
Pages (from-to)73-84
Number of pages12
JournalMarine Ecology Progress Series
Volume355
DOIs
Publication statusPublished - 26 Feb 2008

Fingerprint

deep sea
turnover
abyssal plain
community response
experiment
euphotic zone
polychaete
particulate organic matter
benthos
plasticity
algal bloom
community structure
seafloor
food
carbon
biomass
summer
energy
in situ
benthic ecosystem

Cite this

@article{da5fd2dbd9904ea5bee97e79d3c010f0,
title = "Response of an abyssal macrofaunal community to a phytodetrital pulse",
abstract = "The majority of deep-sea benthic communities rely on particulate organic matter (POM) sinking from the euphotic zone for energy, much of which is delivered in pulsed events. But we know little about abyssal plain macrofaunal communities, their response to such events or their role in deep-sea carbon-cycling. In this study, we examined the composition of the macrofaunal community at Station M in the deep NE Pacific and assessed its short-term response to a simulated OM pulse in two 36 h in situ enrichment experiments. In each experiment, 1.2 gC m–2 of 13C-labelled Skeletonema costatum was deposited onto the seafloor using a benthic chamber lander. Macrofaunal abundance and biomass were significantly higher at 0 to 5 cm depth compared to 5 to 10 cm, and were dominated by the Nematoda and Crustacea, respectively. Twenty-five percent of the macrofauna specimens showed 13C signatures indicative of label ingestion, but specific uptake (Δδ13C) and C-turnover rates varied strongly between and within taxa. Two organisms, a single cumacean from 1 chamber and a paraonid polychaete from the second chamber, were responsible for the majority of C-uptake and had ingested up to 2.3{\%} of their body weight in C. Macrofaunal C-turnover was much lower than recorded in the abyssal NE Atlantic, which is most likely due to differences in the timing of the experiments relative to the spring/summer bloom, different experimental durations and disparities in macrofaunal community structure. These results emphasize the degree of plasticity inherent in the macrofaunal response to a food pulse and stress the need for comprehensive in situ investigations to further our understanding of deep-sea benthic ecosystem functioning.",
author = "Sweetman, {Andrew K.} and Ursula Witte",
year = "2008",
month = "2",
day = "26",
doi = "10.3354/meps07240",
language = "English",
volume = "355",
pages = "73--84",
journal = "Marine Ecology Progress Series",
issn = "0171-8630",
publisher = "Inter-Research",

}

Response of an abyssal macrofaunal community to a phytodetrital pulse. / Sweetman, Andrew K.; Witte, Ursula.

In: Marine Ecology Progress Series, Vol. 355, 26.02.2008, p. 73-84.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Response of an abyssal macrofaunal community to a phytodetrital pulse

AU - Sweetman, Andrew K.

AU - Witte, Ursula

PY - 2008/2/26

Y1 - 2008/2/26

N2 - The majority of deep-sea benthic communities rely on particulate organic matter (POM) sinking from the euphotic zone for energy, much of which is delivered in pulsed events. But we know little about abyssal plain macrofaunal communities, their response to such events or their role in deep-sea carbon-cycling. In this study, we examined the composition of the macrofaunal community at Station M in the deep NE Pacific and assessed its short-term response to a simulated OM pulse in two 36 h in situ enrichment experiments. In each experiment, 1.2 gC m–2 of 13C-labelled Skeletonema costatum was deposited onto the seafloor using a benthic chamber lander. Macrofaunal abundance and biomass were significantly higher at 0 to 5 cm depth compared to 5 to 10 cm, and were dominated by the Nematoda and Crustacea, respectively. Twenty-five percent of the macrofauna specimens showed 13C signatures indicative of label ingestion, but specific uptake (Δδ13C) and C-turnover rates varied strongly between and within taxa. Two organisms, a single cumacean from 1 chamber and a paraonid polychaete from the second chamber, were responsible for the majority of C-uptake and had ingested up to 2.3% of their body weight in C. Macrofaunal C-turnover was much lower than recorded in the abyssal NE Atlantic, which is most likely due to differences in the timing of the experiments relative to the spring/summer bloom, different experimental durations and disparities in macrofaunal community structure. These results emphasize the degree of plasticity inherent in the macrofaunal response to a food pulse and stress the need for comprehensive in situ investigations to further our understanding of deep-sea benthic ecosystem functioning.

AB - The majority of deep-sea benthic communities rely on particulate organic matter (POM) sinking from the euphotic zone for energy, much of which is delivered in pulsed events. But we know little about abyssal plain macrofaunal communities, their response to such events or their role in deep-sea carbon-cycling. In this study, we examined the composition of the macrofaunal community at Station M in the deep NE Pacific and assessed its short-term response to a simulated OM pulse in two 36 h in situ enrichment experiments. In each experiment, 1.2 gC m–2 of 13C-labelled Skeletonema costatum was deposited onto the seafloor using a benthic chamber lander. Macrofaunal abundance and biomass were significantly higher at 0 to 5 cm depth compared to 5 to 10 cm, and were dominated by the Nematoda and Crustacea, respectively. Twenty-five percent of the macrofauna specimens showed 13C signatures indicative of label ingestion, but specific uptake (Δδ13C) and C-turnover rates varied strongly between and within taxa. Two organisms, a single cumacean from 1 chamber and a paraonid polychaete from the second chamber, were responsible for the majority of C-uptake and had ingested up to 2.3% of their body weight in C. Macrofaunal C-turnover was much lower than recorded in the abyssal NE Atlantic, which is most likely due to differences in the timing of the experiments relative to the spring/summer bloom, different experimental durations and disparities in macrofaunal community structure. These results emphasize the degree of plasticity inherent in the macrofaunal response to a food pulse and stress the need for comprehensive in situ investigations to further our understanding of deep-sea benthic ecosystem functioning.

U2 - 10.3354/meps07240

DO - 10.3354/meps07240

M3 - Article

VL - 355

SP - 73

EP - 84

JO - Marine Ecology Progress Series

JF - Marine Ecology Progress Series

SN - 0171-8630

ER -