Dynamic and functional response of benthic foraminifera and macrofauna in oyster farming area in the Pertuis Charentais
In oyster farming areas, organic matter fluxes toward sediment is increased. Pacific oysters (Crassostrea gigas) reject organic-rich faeces and pseudofaeces as a result of filtration process. Organic matter can be consumed by benthic fauna, but in excess it can entails the reduction of benthic fauna...
Main Author: | |
---|---|
Other Authors: | , , , |
Format: | Doctoral or Postdoctoral Thesis |
Language: | French |
Published: |
HAL CCSD
2007
|
Subjects: | |
Online Access: | https://theses.hal.science/tel-00345844 https://theses.hal.science/tel-00345844v2/document https://theses.hal.science/tel-00345844v2/file/Bouchet_2007_PhD.pdf |
id |
ftunivangershal:oai:HAL:tel-00345844v2 |
---|---|
record_format |
openpolar |
spelling |
ftunivangershal:oai:HAL:tel-00345844v2 2023-11-12T04:16:19+01:00 Dynamic and functional response of benthic foraminifera and macrofauna in oyster farming area in the Pertuis Charentais Dynamique et réponse fonctionnelle des foraminifères et de la macrofaune benthique en zone ostreicole dans les pertuis charentais Bouchet, Vincent M.P. Bio-Indicateurs Actuels et Fossiles (BIAF) Université d'Angers (UA) Université d'Angers Mr Jean-Pierre Debenay 2007-06-27 https://theses.hal.science/tel-00345844 https://theses.hal.science/tel-00345844v2/document https://theses.hal.science/tel-00345844v2/file/Bouchet_2007_PhD.pdf fr fre HAL CCSD tel-00345844 https://theses.hal.science/tel-00345844 https://theses.hal.science/tel-00345844v2/document https://theses.hal.science/tel-00345844v2/file/Bouchet_2007_PhD.pdf info:eu-repo/semantics/OpenAccess https://theses.hal.science/tel-00345844 Planète et Univers [physics]. Université d'Angers, 2007. Français. ⟨NNT : ⟩ Oyster farming intertidal areas granulometry organic matter chlorophyl a benthic macrofauna benthic foraminifera tolerant species sensible species macrofauna/foraminifera interactions Ostréiculture pertuis charentais zone intertidale granulométrie matière organique chlorophylle a macrofaune benthique foraminifères benthiques espèces tolérantes espèces sensibles interaction macrofaune/foraminifères bioturbation CAT-scan [SDU]Sciences of the Universe [physics] info:eu-repo/semantics/doctoralThesis Theses 2007 ftunivangershal 2023-10-25T16:18:13Z In oyster farming areas, organic matter fluxes toward sediment is increased. Pacific oysters (Crassostrea gigas) reject organic-rich faeces and pseudofaeces as a result of filtration process. Organic matter can be consumed by benthic fauna, but in excess it can entails the reduction of benthic faunal species richness, abundance and biomass. Organic matter degradation also induces hypoxic (or anoxic) conditions in the sediment, and production of ammonia and sulfides in toxic concentrations. The main objective of this study is to assess the effects of oyster farming on benthic intertidal ecosystems in the Pertuis Charentais. Benthic macrofauna, living (stained) foraminifera, and physicochemical characteristics of the water column and sediment were used as indicators to evaluate these effects. A multidisciplinary approach was conducted across the Pertuis Charentais at 3 different spatial scales: an oyster trestle (micro-scale), an oyster culture area (meso-scale) and various sites across the Pertuis Charentais (macro-scale). The study was also realised at 4 different temporal scales: some months for the spatial micro-scale, every two weeks for 2 years at meso-scale and once per season during one year at macro-scale. In this study, I found that oyster farming enriches sediment in fine particles, organic matter (up to 12 %), particulate organic carbon (15-20 μg mg-1) and leads to high microphytobenthic biomass. Moreover, the association of seasonnal warming (during spring and summer), remineralisation of accumulated organic matter and short-term hypoxic conditions leads to sulfides and ammonium production. Consequently, the benthic biodiversity decreases and the population dynamic is disturbed. The population dynamic disturbance is characterised by fast abundance rises followed by high mortality rates. In these conditions, tolerant benthic macrofaunal (Cirratulidae, Spionidae and Capitellidae) and foraminiferal (Ammonia tepida and Cribroelphidium gunteri) species are promoted. AMBI index confirms “medium” ecological ... Doctoral or Postdoctoral Thesis Crassostrea gigas Portail des publications scientifiques de l’Université d’Angers (HAL) Pacific |
institution |
Open Polar |
collection |
Portail des publications scientifiques de l’Université d’Angers (HAL) |
op_collection_id |
ftunivangershal |
language |
French |
topic |
Oyster farming intertidal areas granulometry organic matter chlorophyl a benthic macrofauna benthic foraminifera tolerant species sensible species macrofauna/foraminifera interactions Ostréiculture pertuis charentais zone intertidale granulométrie matière organique chlorophylle a macrofaune benthique foraminifères benthiques espèces tolérantes espèces sensibles interaction macrofaune/foraminifères bioturbation CAT-scan [SDU]Sciences of the Universe [physics] |
spellingShingle |
Oyster farming intertidal areas granulometry organic matter chlorophyl a benthic macrofauna benthic foraminifera tolerant species sensible species macrofauna/foraminifera interactions Ostréiculture pertuis charentais zone intertidale granulométrie matière organique chlorophylle a macrofaune benthique foraminifères benthiques espèces tolérantes espèces sensibles interaction macrofaune/foraminifères bioturbation CAT-scan [SDU]Sciences of the Universe [physics] Bouchet, Vincent M.P. Dynamic and functional response of benthic foraminifera and macrofauna in oyster farming area in the Pertuis Charentais |
topic_facet |
Oyster farming intertidal areas granulometry organic matter chlorophyl a benthic macrofauna benthic foraminifera tolerant species sensible species macrofauna/foraminifera interactions Ostréiculture pertuis charentais zone intertidale granulométrie matière organique chlorophylle a macrofaune benthique foraminifères benthiques espèces tolérantes espèces sensibles interaction macrofaune/foraminifères bioturbation CAT-scan [SDU]Sciences of the Universe [physics] |
description |
In oyster farming areas, organic matter fluxes toward sediment is increased. Pacific oysters (Crassostrea gigas) reject organic-rich faeces and pseudofaeces as a result of filtration process. Organic matter can be consumed by benthic fauna, but in excess it can entails the reduction of benthic faunal species richness, abundance and biomass. Organic matter degradation also induces hypoxic (or anoxic) conditions in the sediment, and production of ammonia and sulfides in toxic concentrations. The main objective of this study is to assess the effects of oyster farming on benthic intertidal ecosystems in the Pertuis Charentais. Benthic macrofauna, living (stained) foraminifera, and physicochemical characteristics of the water column and sediment were used as indicators to evaluate these effects. A multidisciplinary approach was conducted across the Pertuis Charentais at 3 different spatial scales: an oyster trestle (micro-scale), an oyster culture area (meso-scale) and various sites across the Pertuis Charentais (macro-scale). The study was also realised at 4 different temporal scales: some months for the spatial micro-scale, every two weeks for 2 years at meso-scale and once per season during one year at macro-scale. In this study, I found that oyster farming enriches sediment in fine particles, organic matter (up to 12 %), particulate organic carbon (15-20 μg mg-1) and leads to high microphytobenthic biomass. Moreover, the association of seasonnal warming (during spring and summer), remineralisation of accumulated organic matter and short-term hypoxic conditions leads to sulfides and ammonium production. Consequently, the benthic biodiversity decreases and the population dynamic is disturbed. The population dynamic disturbance is characterised by fast abundance rises followed by high mortality rates. In these conditions, tolerant benthic macrofaunal (Cirratulidae, Spionidae and Capitellidae) and foraminiferal (Ammonia tepida and Cribroelphidium gunteri) species are promoted. AMBI index confirms “medium” ecological ... |
author2 |
Bio-Indicateurs Actuels et Fossiles (BIAF) Université d'Angers (UA) Université d'Angers Mr Jean-Pierre Debenay |
format |
Doctoral or Postdoctoral Thesis |
author |
Bouchet, Vincent M.P. |
author_facet |
Bouchet, Vincent M.P. |
author_sort |
Bouchet, Vincent M.P. |
title |
Dynamic and functional response of benthic foraminifera and macrofauna in oyster farming area in the Pertuis Charentais |
title_short |
Dynamic and functional response of benthic foraminifera and macrofauna in oyster farming area in the Pertuis Charentais |
title_full |
Dynamic and functional response of benthic foraminifera and macrofauna in oyster farming area in the Pertuis Charentais |
title_fullStr |
Dynamic and functional response of benthic foraminifera and macrofauna in oyster farming area in the Pertuis Charentais |
title_full_unstemmed |
Dynamic and functional response of benthic foraminifera and macrofauna in oyster farming area in the Pertuis Charentais |
title_sort |
dynamic and functional response of benthic foraminifera and macrofauna in oyster farming area in the pertuis charentais |
publisher |
HAL CCSD |
publishDate |
2007 |
url |
https://theses.hal.science/tel-00345844 https://theses.hal.science/tel-00345844v2/document https://theses.hal.science/tel-00345844v2/file/Bouchet_2007_PhD.pdf |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
Crassostrea gigas |
genre_facet |
Crassostrea gigas |
op_source |
https://theses.hal.science/tel-00345844 Planète et Univers [physics]. Université d'Angers, 2007. Français. ⟨NNT : ⟩ |
op_relation |
tel-00345844 https://theses.hal.science/tel-00345844 https://theses.hal.science/tel-00345844v2/document https://theses.hal.science/tel-00345844v2/file/Bouchet_2007_PhD.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1782333445633998848 |