Data/hora: 08/06/2024 09:33:04

Provedor de dados: | 5
País: | France

Título:

Effet d’une espèce ingénieur sur la diversité et le fonctionnement des communautés benthiques : l’habitat récifal à Sabellaria alveolata

Effect of an engineer species on the diversity and functioning of benthic communities : the Sabellaria Alveolata reef habitat

Autores: | Jones, Auriane.
Data: | 2017-12-14
Ano: | 2017
Palavras-chave: | Ingénieur de l’écosystème; Habitat récifal; Macrofaune benthique; Diversité fonctionnelle et isotopique; Production primaire benthique; Réseau trophique; Flux biogéochimiques; Traits biologiques; Ecosystem engineer; Reef habitat; Benthic macrofauna; Functional and isotopic diversity; Facilitation; Benthic primary production; Food web; Biogeochemical fluxes; Isoscape; Biological traits.
Resumo: | Coastal zones worldwide are home to a large diversity of ecosystem engineers that perform key functions such as the recycling of organic matter and nutrients. The habitats resulting from the biological activity of these species are exposed to numerous disturbances such as over harvesting and trampling or via coastal modification. In this context, it is becoming key to understand the functioning of these engineered habitats and how they are affected by increasing disturbances. During my PhD, I used the reef habitat built by the gregarious tubiculous polychaete Sabellaria alveolata as a study case. First, the environmental and biotic changes associated with the establishment of a S. alveolata reef and its increasing disturbance were assessed, focusing on sediment characteristics (e.g. grain-size distribution, organic matter content) along with taxonomic diversity and species assemblage. In the same vain, the third article looks into the trophic functioning of the reef community and a control community to understand the effects of the establishment of the engineer species on carbon transfers, successively looking at the whole consumer community, the primary consumers and the importance of autochthonous (microphytobenthos and Ulva sp.) vs allochthone (phytoplankton) food sources. In this part, I used carbon and nitrogen stable isotopes and different analytical approaches such as isotopic niche metrics and mixing models. Article 2 aims towards understanding the interactions between reef habitat complexity, autochthonous food source heterogeneity and spatial scales in explaining the carbon isotopic ratio variations of S. alveolata and an associated suspension-feeder. In the last two chapters, I address the functioning of the engineered habitat either directly, using benthic core incubations to measure biogeochemical fluxes (e.g. oxygen demand) or indirectly, through the use of integrative functional and isotopic diversity indices. This last part reveals the existence of an optimum value of S. alveolata density, used as a disturbance proxy, where the trophic niche and the biogeochemical functioning of the reef are both maximal.
Tipo: | Text
Idioma: | Francês

Identificador:

https://archimer.ifremer.fr/doc/00498/60960/64363.pdf

https://archimer.ifremer.fr/doc/00498/60960/

Editor: | Université de Bretagne occidentale
Formato: | application/pdf

Fonte:

info:eu-repo/semantics/openAccess

restricted use