Data/hora: 01/06/2024 14:46:29

Provedor de dados: 	5	
País: 	France	
Título: 	Short term variability of dissolved lipid classes during summer to autumn transition in the Ligurian sea (NW Mediterranean)	
Autores: 	Goutx, M.; Guigue, C.; Aritio, D.; Ghiglione, J.; Pujo-pay, M.; Andersen, V.	
Data: 	2009	
Ano: 	2009	
Resumo: 	Changes in concentration and composition of dissolved lipid classes (Iatroscan TLC/FID) were examined at daily to month scale, in relation to the hydrological and biological situation at a central site of the Ligurian sea, NW Mediterranean during the PECHE-DYNAPROC 2 experiment (14 September to 17 October). Dissolved lipid concentrations (TLd) and lipid to DOC ratios varied in the range 5.3–48.5 μg l−1 and 0.01 to 0.08 respectively, along the 0–1000m water column. The highest TLd concentration values were found in the 0–150m surface layer coinciding with phytoplankton biomass. Lipid class composition provided valuable information on the origin of DOM, and the changes that occurred during the period investigated. The significant correlations (p&lt;0.01, n=87) between glycolipids from chloroplast membrane (MGDG) (38.7±8.5% of TLd, n=166), and various phytoplankton pigments (chlorophyll cs-170, violaxanthin, diadinoxanthin, zeaxanthin, and lutein), suggested that picoeucaryotes were the major source of dissolved lipids. Lipid metabolites (37.6±11.1%, n=166), the second most important compounds in TLd, showed a greater degree of degradation of lipids in this transition period than previously observed earlier in the year. A contribution of lipids to DOM in the mesopelagic zone was observed before the winter mixing: At mid time of the cruise (4–6 October), zooplankton wax esters biomarkers (WE, 5.5–13.6 μg L−1) appeared in the 0–150m surface layer. WE were observed later and deeper in the mesopelagic layer (6 to 11 October), accompanied by re-increases of hydrocarbons (6–8 October) and phospholipids concentrations (12 October) in the 400–1000m depth layer. Zooplankton migration and/or fecal pellets egestion, followed by DOM release from POM, were likely responsible for the appearance of these lipid signatures in the mesopelagic layer, which occurred during the period of low wind (&lt;15 knots) (28 September–12 October). The low salinity water lenses that appeared twice during the cruise in the 40–80m surface layer had little effect on total biogenic lipid concentrations. Lower concentrations in phosphoglycerides and hydrocarbons than the nearby sea water suggested different microbial assemblages and different	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	https://archimer.ifremer.fr/doc/00212/32330/30788.pdf

DOI:10.5194/bgd-6-27-2009

https://archimer.ifremer.fr/doc/00212/32330/	
Editor: 	Copernicus Publications	
Formato: 	application/pdf	
Fonte: 	Biogeosciences Discussions (1810-6285) (Copernicus Publications), 2009 , Vol. 6 , P. 27-69	
Fonte: 	Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License.

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