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J C Marty

Publications and source records attributed to J C Marty.

14 recordsLinked to original sources
PubMed1992

Fatty acid composition in deep hydrothermal vent symbiotic bivalves.

Fatty acids in deep hydrothermal vent bivalves have been analyzed. Their composition is completely different from that of a littoral mussel collected in the Mediterranean sea. The distribution of fatty acids in the littoral mussel is characterized by a predominance of polyunsaturated fatty acids (20:5n-3, 22:6n-3) reflecting the planktonic origin of the food. Vent bivalve fatty acid distribution is dominated by an abundance of the monounsaturated acids (double bond in the n-7 position) 16:1n-7, 18:1n-7, and 20:1n-7 which are clearly of bacterial origin and give an indication of the symbiotic bacterial activity in the bivalves. Differences between the fatty acid composition of the bivalves from two hydrothermal sites (13 degrees N and Galapagos) and differences between the mantle and the gill were observed and are discussed with respect to vent activities at the two sites and species metabolic capacities as a function of ecological conditions.

Animals↗
PubMed1987

Aliphatic and aromatic hydrocarbons in the mediterranean aerosol.

The atmospheric transport of organic pollutants over long distances and their effect on the biological cycles of the sea are two major questions of concern in environmental chemistry. These processes are of particular importance in the Mediterranean Sea because of its semi-enclosed characteristics, which determine the accumulation of the pollutants entering into the system. In order to get some insight into these processes a project (PHYCEMED), was developed for the evaluation of the atmospheric budget of organic and inorganic substances in the Western Mediterranean and for the investigation of the exchange mechanisms of these materials across the air/sea interface. A high volume air sampling system including a cascade impactor was placed on board of the R/V le Suroit for collecting the aerosols along several transects parallel to the French, Spanish and North-African coasts, facing areas of different population densities and industrial activities. The cruise was realised on October 1983 and the particulate material was fractionated into the following sizes: 7.2, 3.0, 1.5, 0.96, and 0.03 micron. Quantitative and qualitative analyses of the aliphatic and the aromatic hydrocarbons present in these fractions were performed by high resolution gas chromatography and gas chromatography-mass spectrometry.

Air Movements↗
PubMed1982

Hydrocarbons in the Western Mediterranean Sea, 1981.

Hydrocarbons in the western Mediterranean Sea were analysed for surface microlayer and subsurface waters during April 1981. Three methods were used for determining both concentrations and markers distribution patterns: U.V. spectrofluorimetry, and original HPLC/U.V. spectrophotometry method and capillary gas liquid chromatography. No systematic relationship was found between concentrations determined by U.V. spectrofluorimetry and HPLC/U.V. spectrophotometry. Concentrations variation ranges are: 0.01-0.20 microgram 1(-1) for dissolved aromatic hydrocarbons; 0.02-0.13 microgram 1(-1) for particulate aromatic hydrocarbons; 0.02-20.57 micrograms 1(-1) for dissolved n-alkanes; 0.13-0.83 microgram 1(-1) for particulate n-alkanes. Surficial waters appear as very slightly polluted with an exception the Ligurian Sea for which highest concentrations were encountered. There is a slight enrichment of particulate hydrocarbons in the surface microlayer in the range 1-3. But, dissolved hydrocarbons can be either depleted or enriched up to 270 times in the surface microlayer, indicating the extreme efficiency of sea-air exchange processes. Aromatic fingerprints and n-alkane distribution patterns are discussed both for pollution and fractionation processes indicators at the sea-air interface.

Hydrocarbons↗