Effect of atmospheric nutrients on the autotrophic communities in a low nutrient, low chlorophyll system

Sophie Bonnet, Cecile Guieu, Jacques Chiaverini, Joséphine Ras, Agnès Stock

Research output: Contribution to journalArticle

Abstract

The effect of atmospheric inputs on phytoplanktonic dynamics was investigated in the Mediterranean Sea during the season characterized by a stratified water column, low primary productivity, and low concentrations of nutrients ([nitrate] < 50 nmol L-1; [phosphate] = 20 nmol L -1; [silicate] = 0.7 μmol L-1). We report here data obtained during microcosm enrichment experiments performed on the natural assemblage using different combinations of realistic additions (Saharan dust, Fe, Fe + phosphate, and anthropogenic particles). Saharan dust and Fe + phosphate treatments significantly stimulated primary production. Anthropogenic particles and Fe + phosphate treatments increased the chlorophyll a concentrations, enhancing mainly the small cells (pico- and nanophytoplankton). The autotrophic community structure was significantly altered; for example, Fe and Fe + phosphate additions benefited prokaryotic populations, indicating possible nitrogen fixation. The colimitation of both phosphate and Fe was removed by these additions. Results emphasized the effect of Fe, although the ambient concentration was close to 1 nmol L-1. The addition of dust benefited eukaryotic populations, which indicates that the dust was a possible source of nitrogen. An abiotic dissolution experiment of macronutrients attached to dust confirmed this hypothesis. The dissolution of Fe attached to the dust (0.23-0.61%) and to the anthropogenic particles (0.86-1.85%) was consistent with previous studies conducted under abiotic conditions. This result suggests that the possible enhancement of the dissolution processes caused by biological activity might have been balanced by Fe consumption by the biota and its adsorption on both mineral and organic particles.

Original languageEnglish (US)
Pages (from-to)1810-1819
Number of pages10
JournalLimnology and Oceanography
Volume50
Issue number6
DOIs
StatePublished - Jan 1 2005

Fingerprint

dust
chlorophyll
phosphate
phosphates
nutrient
nutrients
dissolution
primary productivity
nitrogen fixation
silicates
Mediterranean Sea
microcosm
effect
primary production
bioactive properties
biota
chlorophyll a
adsorption
community structure
nutrient content

ASJC Scopus subject areas

  • Oceanography
  • Aquatic Science

Cite this

Effect of atmospheric nutrients on the autotrophic communities in a low nutrient, low chlorophyll system. / Bonnet, Sophie; Guieu, Cecile; Chiaverini, Jacques; Ras, Joséphine; Stock, Agnès.

In: Limnology and Oceanography, Vol. 50, No. 6, 01.01.2005, p. 1810-1819.

Research output: Contribution to journalArticle

Bonnet, Sophie ; Guieu, Cecile ; Chiaverini, Jacques ; Ras, Joséphine ; Stock, Agnès. / Effect of atmospheric nutrients on the autotrophic communities in a low nutrient, low chlorophyll system. In: Limnology and Oceanography. 2005 ; Vol. 50, No. 6. pp. 1810-1819.
@article{330b029d01c14cf39c6f60a011d04174,
title = "Effect of atmospheric nutrients on the autotrophic communities in a low nutrient, low chlorophyll system",
abstract = "The effect of atmospheric inputs on phytoplanktonic dynamics was investigated in the Mediterranean Sea during the season characterized by a stratified water column, low primary productivity, and low concentrations of nutrients ([nitrate] < 50 nmol L-1; [phosphate] = 20 nmol L -1; [silicate] = 0.7 μmol L-1). We report here data obtained during microcosm enrichment experiments performed on the natural assemblage using different combinations of realistic additions (Saharan dust, Fe, Fe + phosphate, and anthropogenic particles). Saharan dust and Fe + phosphate treatments significantly stimulated primary production. Anthropogenic particles and Fe + phosphate treatments increased the chlorophyll a concentrations, enhancing mainly the small cells (pico- and nanophytoplankton). The autotrophic community structure was significantly altered; for example, Fe and Fe + phosphate additions benefited prokaryotic populations, indicating possible nitrogen fixation. The colimitation of both phosphate and Fe was removed by these additions. Results emphasized the effect of Fe, although the ambient concentration was close to 1 nmol L-1. The addition of dust benefited eukaryotic populations, which indicates that the dust was a possible source of nitrogen. An abiotic dissolution experiment of macronutrients attached to dust confirmed this hypothesis. The dissolution of Fe attached to the dust (0.23-0.61{\%}) and to the anthropogenic particles (0.86-1.85{\%}) was consistent with previous studies conducted under abiotic conditions. This result suggests that the possible enhancement of the dissolution processes caused by biological activity might have been balanced by Fe consumption by the biota and its adsorption on both mineral and organic particles.",
author = "Sophie Bonnet and Cecile Guieu and Jacques Chiaverini and Jos{\'e}phine Ras and Agn{\`e}s Stock",
year = "2005",
month = "1",
day = "1",
doi = "10.4319/lo.2005.50.6.1810",
language = "English (US)",
volume = "50",
pages = "1810--1819",
journal = "Limnology and Oceanography",
issn = "0024-3590",
publisher = "American Society of Limnology and Oceanography Inc.",
number = "6",

}

TY - JOUR

T1 - Effect of atmospheric nutrients on the autotrophic communities in a low nutrient, low chlorophyll system

AU - Bonnet, Sophie

AU - Guieu, Cecile

AU - Chiaverini, Jacques

AU - Ras, Joséphine

AU - Stock, Agnès

PY - 2005/1/1

Y1 - 2005/1/1

N2 - The effect of atmospheric inputs on phytoplanktonic dynamics was investigated in the Mediterranean Sea during the season characterized by a stratified water column, low primary productivity, and low concentrations of nutrients ([nitrate] < 50 nmol L-1; [phosphate] = 20 nmol L -1; [silicate] = 0.7 μmol L-1). We report here data obtained during microcosm enrichment experiments performed on the natural assemblage using different combinations of realistic additions (Saharan dust, Fe, Fe + phosphate, and anthropogenic particles). Saharan dust and Fe + phosphate treatments significantly stimulated primary production. Anthropogenic particles and Fe + phosphate treatments increased the chlorophyll a concentrations, enhancing mainly the small cells (pico- and nanophytoplankton). The autotrophic community structure was significantly altered; for example, Fe and Fe + phosphate additions benefited prokaryotic populations, indicating possible nitrogen fixation. The colimitation of both phosphate and Fe was removed by these additions. Results emphasized the effect of Fe, although the ambient concentration was close to 1 nmol L-1. The addition of dust benefited eukaryotic populations, which indicates that the dust was a possible source of nitrogen. An abiotic dissolution experiment of macronutrients attached to dust confirmed this hypothesis. The dissolution of Fe attached to the dust (0.23-0.61%) and to the anthropogenic particles (0.86-1.85%) was consistent with previous studies conducted under abiotic conditions. This result suggests that the possible enhancement of the dissolution processes caused by biological activity might have been balanced by Fe consumption by the biota and its adsorption on both mineral and organic particles.

AB - The effect of atmospheric inputs on phytoplanktonic dynamics was investigated in the Mediterranean Sea during the season characterized by a stratified water column, low primary productivity, and low concentrations of nutrients ([nitrate] < 50 nmol L-1; [phosphate] = 20 nmol L -1; [silicate] = 0.7 μmol L-1). We report here data obtained during microcosm enrichment experiments performed on the natural assemblage using different combinations of realistic additions (Saharan dust, Fe, Fe + phosphate, and anthropogenic particles). Saharan dust and Fe + phosphate treatments significantly stimulated primary production. Anthropogenic particles and Fe + phosphate treatments increased the chlorophyll a concentrations, enhancing mainly the small cells (pico- and nanophytoplankton). The autotrophic community structure was significantly altered; for example, Fe and Fe + phosphate additions benefited prokaryotic populations, indicating possible nitrogen fixation. The colimitation of both phosphate and Fe was removed by these additions. Results emphasized the effect of Fe, although the ambient concentration was close to 1 nmol L-1. The addition of dust benefited eukaryotic populations, which indicates that the dust was a possible source of nitrogen. An abiotic dissolution experiment of macronutrients attached to dust confirmed this hypothesis. The dissolution of Fe attached to the dust (0.23-0.61%) and to the anthropogenic particles (0.86-1.85%) was consistent with previous studies conducted under abiotic conditions. This result suggests that the possible enhancement of the dissolution processes caused by biological activity might have been balanced by Fe consumption by the biota and its adsorption on both mineral and organic particles.

UR - http://www.scopus.com/inward/record.url?scp=28044459663&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=28044459663&partnerID=8YFLogxK

U2 - 10.4319/lo.2005.50.6.1810

DO - 10.4319/lo.2005.50.6.1810

M3 - Article

AN - SCOPUS:28044459663

VL - 50

SP - 1810

EP - 1819

JO - Limnology and Oceanography

JF - Limnology and Oceanography

SN - 0024-3590

IS - 6

ER -