Carbon and Nitrogen Isotopic Ratios of the Seagrass Posidonia oceanica: Depth-related Variations
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Abstract
Nitrogen (δ15N) and carbon (δ13C) isotopic compositions of Posidonia oceanica were determined during three seasons along a bathymetric gradient (4–38m depth).The δ15N values are low (2.2±0.9 ‰ ) and variable. They do not show any relation to depth or sampling dates. There is a significant difference between the δ15N values of the youngest and the oldest leaves, probably as a result of N resorption and senescing during leaf ageing. The δ13C values of young Posidonia leaves vary with depth, showing the relationship between δ13C values and primary productivity rate, and the use of a bicarbonate/CO2 mixture as an inorganic carbon source. The δ13C values of the oldest P. oceanica leaves are depleted in 13C compared to those of young leaves. This modification of the 13C signatures in relation to leaf age is particularly important between 20 and 29 m depth. This modification could be related to photosynthetic rate change during ageing, but also to change in carbohydrate composition and content.
Copyright © 2003 by Walter de Gruyter GmbH & Co. KG
Articles in the same Issue
- Contents
- Author Index
- Subject Index
- Taxonomical Index
- Estimating Biomass from the Cover of Gelidiella acerosa along the Coasts of Eastern Philippines
- Photosynthesis, Growth and Nitrogen Uptake of Competing Marine Macrophytes in the Gulf of California
- Patch Distribution and Within-Patch Dynamics of the Seagrass Zostera noltii Hornem. in Los Toruños Salt-Marsh, Cádiz Bay, Natural Park, Spain
- Interannual Variability in Flowering of Posidonia oceanica in the North-Western Mediterranean Sea, and Relationships among Shoot Age and Flowering
- A New Species of Vaucheria Epiphytic on Mangroves
- Taxonomic Notes on Marine Algae from Malaysia. XI. Four Species of Rhodophyceae
- First Record of Ceramium giacconei (Ceramiaceae, Rhodophyta) in the North Pacific: Developmental Morphology of Vegetative and Reproductive Structures
- Carbon and Nitrogen Isotopic Ratios of the Seagrass Posidonia oceanica: Depth-related Variations
- Chemical Composition of Attached and Drift Specimens of Sargassum mangarevense and Turbinaria ornata (Phaeophyta: Fucales) from Tahiti, French Polynesia
- The Chemical Structure of Galactans from Some New Zealand Red Algae
- Proceedings of the XVIIth International Seaweed Symposium, Cape Town, South Africa, 28 January 2 February 2001
- Acknowledgement
- Meetings
Articles in the same Issue
- Contents
- Author Index
- Subject Index
- Taxonomical Index
- Estimating Biomass from the Cover of Gelidiella acerosa along the Coasts of Eastern Philippines
- Photosynthesis, Growth and Nitrogen Uptake of Competing Marine Macrophytes in the Gulf of California
- Patch Distribution and Within-Patch Dynamics of the Seagrass Zostera noltii Hornem. in Los Toruños Salt-Marsh, Cádiz Bay, Natural Park, Spain
- Interannual Variability in Flowering of Posidonia oceanica in the North-Western Mediterranean Sea, and Relationships among Shoot Age and Flowering
- A New Species of Vaucheria Epiphytic on Mangroves
- Taxonomic Notes on Marine Algae from Malaysia. XI. Four Species of Rhodophyceae
- First Record of Ceramium giacconei (Ceramiaceae, Rhodophyta) in the North Pacific: Developmental Morphology of Vegetative and Reproductive Structures
- Carbon and Nitrogen Isotopic Ratios of the Seagrass Posidonia oceanica: Depth-related Variations
- Chemical Composition of Attached and Drift Specimens of Sargassum mangarevense and Turbinaria ornata (Phaeophyta: Fucales) from Tahiti, French Polynesia
- The Chemical Structure of Galactans from Some New Zealand Red Algae
- Proceedings of the XVIIth International Seaweed Symposium, Cape Town, South Africa, 28 January 2 February 2001
- Acknowledgement
- Meetings
