Data/hora: 08/06/2024 11:21:30

Provedor de dados: | 5
País: | France
Título: | Environmental factors affecting maerl bed structure in Brittany (France)
Autores: | Dutertre, Mickael; Grall, Jacques; Ehrhold, Axel; Hamon, Dominique.
Data: | 2015
Ano: | 2015
Palavras-chave: | Benthic habitats; Brittany; Environmental factors; Estuary; Large spatial scale; Maerl.
Resumo: | This study used a large spatial scale approach in order to better quantify the relationships between maerl bed structure and a selection of potentially forcing physical factors. Data on maerl bed structure and morpho-sedimentary characteristics were obtained from recent oceanographic surveys using underwater video recording and grab sampling. Considering the difficulties in carrying out real-time monitoring of highly variable hydrodynamic and physicochemical factors, these were generated by three-dimensional numerical models with high spatial and temporal resolution. The BIOENV procedure indicated that variation in the percentage cover of thalli can best be explained (correlation = 0.76) by a combination of annual mean salinity, annual mean nitrate concentration and annual mean current velocity, while the variation in the proportion of living thalli can best be explained (correlation = 0.47) by a combination of depth and mud content. Linear relationships showed that the percentage cover of maerl thalli was positively correlated with nitrate concentration (R2 = 0.78, P &lt; 0.01) and negatively correlated with salinity (R2 = 0.81, P &lt; 0.01), suggesting a strong effect of estuarine discharge on maerl bed structure, and also negatively correlated with current velocity (R2 = 0.81, P &lt; 0.01). When maerl beds were deeper than 10 m, the proportion of living thalli was always below 30% but when they were shallower than 10 m, it varied between 4 and 100%, and was negatively correlated with mud content (R2 = 0.53, P &lt; 0.01). On the other hand, when mud content was below 10%, the proportion of living thalli showed a negative correlation with depth (R2 = 0.84, P &lt; 0.01). This large spatial scale explanation of maerl bed heterogeneity provides a realistic physical characterization of these ecologically interesting benthic habitats and usable findings for their conservation and management.
Tipo: | Text
Idioma: | Inglês

Identificador:

https://archimer.ifremer.fr/doc/00280/39089/37816.pdf

DOI:10.1080/09670262.2015.1063698

https://archimer.ifremer.fr/doc/00280/39089/

Editor: | Taylor &amp; Francis Ltd
Formato: | application/pdf
Fonte: | European Journal Of Phycology (0967-0262) (Taylor &amp; Francis Ltd), 2015 , Vol. 50 , N. 4 , P. 371-383

Fonte:

2015 British Phycological Society

info:eu-repo/semantics/openAccess

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