References of "Dauby, Patrick"
     in
Bookmark and Share    
Peer Reviewed
See detailExperimental determination of the feeding rate for some Antarctic amphipod species
Dauby, Patrick ULg; Nyssen, Fabienne ULg; Scailteur, Yves et al

Poster (2003, April)

Detailed reference viewed: 13 (0 ULg)
Peer Reviewed
See detailAmphipods: the second food source for top-predators in the Southern Ocean?
Dauby, Patrick ULg; Nyssen, Fabienne ULg; De Broyer, Claude

Poster (2003, April)

Detailed reference viewed: 5 (0 ULg)
See detailParticularités des organismes des abysses et des sources hydrothermales.
Dauby, Patrick ULg; Coulon, Pierre

Article for general public (2003)

Detailed reference viewed: 5 (0 ULg)
Full Text
Peer Reviewed
See detailCarbon and nitrogen isotopic ratios of the seagrass Posidonia oceanica: Depth-related variations
Lepoint, Gilles ULg; Dauby, Patrick ULg; Fontaine, Michael ULg et al

in Botanica Marina (2003), 46(6), 555-561

Nitrogen (delta(15)N) and carbon (delta(13)C) isotopic compositions of Posidonia oceanica were determined during three seasons along a bathymetric gradient (438 m depth).The delta(15)N values are low (2.2 ... [more ▼]

Nitrogen (delta(15)N) and carbon (delta(13)C) isotopic compositions of Posidonia oceanica were determined during three seasons along a bathymetric gradient (438 m depth).The delta(15)N 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 delta(15)N values of the youngest and the oldest leaves, probably as a result of N resorption and senescing during leaf ageing. The delta(13)C values of young Posidonia leaves vary with depth, showing the relationship between delta(13)C values and primary productivity rate, and the use of a bicarbonate/CO2 mixture as an inorganic carbon source. The delta(13)C values of the oldest P. oceanica leaves are depleted in C-13 compared to those of young leaves. This modification of the C-13 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. [less ▲]

Detailed reference viewed: 73 (13 ULg)
See detailAmphipods as food sources for higher trophic levels in the Southern Ocean: a synthesis
Dauby, Patrick ULg; Nyssen, Fabienne ULg; de Broyer, Claude

in Antarctic biology in a global context (2003)

Detailed reference viewed: 26 (6 ULg)
See detailStructural and ecofunctional biodiversity of the amphipod crustacean benthic taxocoenoses in the Southern Ocean
De Broyer, Claude; Chapelle, Gauthier; Duchesne, Paul-André et al

in Belgian Scientific Research Programme on the Antarctic-Phase 4. Vol 1. Marine Biota and Global Change (2003)

Detailed reference viewed: 19 (0 ULg)
Full Text
Peer Reviewed
See detailCTD measurements, with emphasis on Elephant Island surroundings
Dauby, Patrick ULg

in Berichte zur Polar- und Meeresforschung (2003), 470

Detailed reference viewed: 10 (1 ULg)
See detailBiodiversity pattern in the Southern Ocan: lessons from Crustacea.
De Broyer, Claude; Jazdzewski, Krzystov; Dauby, Patrick ULg

in Huiskes, Ad (Ed.) Antarctic Biology in a Global Context (2003)

Detailed reference viewed: 19 (0 ULg)
Full Text
See detailBiodiversity, molecular phylogeny, and trophodynamics of amphipod crustaceans in the Antarctic deep-sea
De Broyer, Claude; Dauby, Patrick ULg; Nyssen, Fabienne et al

in Berichte zur Polar- und Meeresforschung (2003), 470

Detailed reference viewed: 26 (1 ULg)
Full Text
Peer Reviewed
See detailExperimental evidence for N recycling in the leaves of the seagrass Posidonia oceanica
Lepoint, Gilles ULg; Defawe, Olivier; Gobert, Sylvie ULg et al

in Journal of Sea Research (2002), 48(3), 173-179

A one-year in situ experiment using N-15 as a tracer was designed to assess the N recycling in the leaves of the seagrass Posidonia oceanica (L.) Delile. R oceanica was shown to partly recycle the ... [more ▼]

A one-year in situ experiment using N-15 as a tracer was designed to assess the N recycling in the leaves of the seagrass Posidonia oceanica (L.) Delile. R oceanica was shown to partly recycle the internal nitrogen pool of its leaves in order to contribute to new leaf growth. The leaves sampled in June 1999 contained 20% of the quantity of N-15 found in June 1998. N recycling caused a difference between N and biomass turnover rate (0.8 vs 1.3 y(-1)) of Posidonia leaves. This 40% difference should correspond to the contribution of recycled N to the annual N requirement of Posidonia leaves. The N recycling appears to be insufficient to significantly reduce the quantitative impact of N loss due to autumnal leaf fall. However, new leaf growth between June and October is mainly sustained by this recycling because the tracer concentration in new leaves was the same as in the other leaves. By contrast, tracer concentration decreased drastically between October 1998 and June 1999, showing the more important contribution of N uptake during winter and spring. Nevertheless, recycling occurs throughout the year as demonstrated by the presence of tracer in the youngest leaves of shoots sampled one year after the tracer addition. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

Detailed reference viewed: 27 (5 ULg)
See detailA la recherche de la vie dans les profondeurs de l'Océan Antarctique
Dauby, Patrick ULg

Conference given outside the academic context (2002)

Detailed reference viewed: 8 (0 ULg)
Full Text
Peer Reviewed
See detailAnnual nitrogen budget of the seagrass Posidonia oceanica as determined by in situ uptake experiments
Lepoint, Gilles ULg; Millet, S.; Dauby, Patrick ULg et al

in Marine Ecology. Progress Series (2002), 237

The uptake of nitrate and ammonium by the roots and leaves of Posidonia oceanica were determined between February 1993 and June 1999 by in situ experiments using the isotope 15 of nitrogen (N-15) as a ... [more ▼]

The uptake of nitrate and ammonium by the roots and leaves of Posidonia oceanica were determined between February 1993 and June 1999 by in situ experiments using the isotope 15 of nitrogen (N-15) as a tracer in a nutrient-poor coastal zone of the NW Mediterranean Sea (Revellata Bay, Corsica). Nitrate and ammonium leaf uptakes are recorded at 0.05 and 0.1 muM respectively. The high variability observed cannot be explained solely by the variation of the substrate concentrations in the water column. For leaves, mean specific uptake rates were 43 +/- 45 and 43 +/- 64 mug N g N-1 h(-1). Nitrate and ammonium leaf uptake fluxes (g N m(-2) yr(-1)) seem to have the same importance on an annual basis. :Nitrate uptake occurs mainly in winter and early spring, when nitrate concentrations in the water column are highest. The uptake of N, and mainly of ammonium, is significant throughout the year with maxima at the beginning of spring, but it is insufficient to meet the annual N requirement of the plant. Posidonia root biomass was very high and corresponded to high specific N uptake rates by the roots. Ammonium was incorporated by the roots 6 times faster than nitrate. In the sediment, this uptake capacity is limited by the nutrient diffusion rate, and the root uptake is therefore insufficient to meet the N requirements of the plant. In fact, P. oceanica of Revellata Bay have a complex N budget involving uptake and recycling processes and allowing the plants to meet their N requirements in one of the most nutrient-poor areas of the NW Mediterranean Sea. We calculated that leaf and root would contribute to 40 and 60% of the annual N uptake, respectively, and 60% of the annual N requirement of the plant. [less ▲]

Detailed reference viewed: 114 (14 ULg)
Peer Reviewed
See detailAmphipods: The second food source for top-predators in the Southern Ocean?
Dauby, Patrick ULg; Nyssen, Fabienne; De Broyer, Claude

Poster (2002, July)

Detailed reference viewed: 3 (0 ULg)
Full Text
Peer Reviewed
See detailCarbon and nitrogen stable isotope ratios of subtidal benthic invertebrates in an estuarine mangrove ecosystem (Andhra Pradesh, India)
Bouillon, Steven; Raman, A. V.; Dauby, Patrick ULg et al

in Estuarine Coastal and Shelf Science (2002), 54(5), 901-913

In order to assess the relative trophic importance of mangrove litterfall and aquatic primary production in the mangrove creeks of the Coringa Wildlife Sanctuary (Andhra Pradesh, India) and the adjacent ... [more ▼]

In order to assess the relative trophic importance of mangrove litterfall and aquatic primary production in the mangrove creeks of the Coringa Wildlife Sanctuary (Andhra Pradesh, India) and the adjacent semi-enclosed Kakinada Bay, carbon and nitrogen stable isotope ratios were determined in a variety of benthic invertebrate species collected at 22 sites during the pre-monsoon period (May-June) of 1997 and 1999. delta(13)C values showed little interspecific variation at any given location, but there was a distinct spatial gradient in consumer delta(13)C values of about 7parts per thousand, with more depleted values in the mangrove creeks ( - 23.6 +/- 0.6parts per thousand), and gradually increasing in the mangrove outlets ( - 21.5 +/- 0.9parts per thousand), a relatively restricted zone in the south-eastern part of Kakinada Bay adjacent to the mangroves ( - 18.8 +/- 0.8parts per thousand), and the central and northern part of the Bay ( - 16.7 +/- 1.4parts per thousand) which opens into the Bay of Bengal. This gradient is much larger than that observed during a previous study in suspended organic matter (maximum about 2.7parts per thousand) and during this study in sediment organic matter (about 1.5-2.5parts per thousand). The observed carbon stable isotope ratios thus suggest a marked selectivity of the benthic invertebrate community for pelagic and benthic microalgal food sources and indicate that mangrove-derived and other terrestrial carbon is not a significant food source for benthic invertebrate communities in this ecosystem during the pre-monsoon period. Furthermore, delta(13)C values of sediment organic matter (SOM) suggest that terrestrial carbon is not a major contributor to the SOM-pool in this ecosystem. Evidence for seaward migration of Penaeid prawns was provided by some individuals caught in the North Bay which displayed low delta(13)C values of characteristic of fauna found in the mangrove creeks or outlets. Nitrogen stable isotope ratios were found to be a useful indicator of trophic level, even though there remained some overlap between delta(15)N values of presumed low and higher trophic levels. Benthic invertebrates showed a delta(15)N gradient of about 3.2parts per thousand between the mangrove creeks and the Central and North Bay whereas sediment delta(15)N values showed a smaller spatial gradient of about 1.6parts per thousand. This gradient which is hypothesized to reflect differences in inorganic nitrogen sources and availability. (C) 2001 Elsevier Science Ltd. All rights reserved. [less ▲]

Detailed reference viewed: 40 (0 ULg)
Peer Reviewed
See detailPotential impact of the main benthic amphipods on the Eastern Weddell Sea shelf ecosystem (Antarctica)
Dauby, Patrick ULg; Scailteur, Yves; Chapelle, Gauthier et al

in Arntz, Wolf; Clarke, Andy (Eds.) Ecological Studies in the Antarctic Sea-Ice Zone (2002)

Detailed reference viewed: 11 (0 ULg)
Peer Reviewed
See detailBiodiversity of the Southern Ocean: the "Ant'Phipoda" Project
De Broyer, Claude; Duchesne, Paul-André; Jazdzewski, Krzyzstof et al

Poster (2001, August)

Detailed reference viewed: 2 (0 ULg)
Peer Reviewed
See detailAmphipods as food sources for higher trophic levels in the Southern Ocean
Dauby, Patrick ULg; Nyssen, Fabienne; De Broyer, Claude

Conference (2001, August)

Detailed reference viewed: 9 (0 ULg)
Peer Reviewed
See detailThe role of benthic amphipods in the eastern Weddell Sea trophic web as determined from stable isotope and fatty acid analyses
Nyssen, Fabienne ULg; Brey, Thomas; Graeve, Martin et al

Conference (2001, August)

Within the Southern Ocean, amphipods have achieved a conspicuous adaptative radiation which gave rise to the development of numerous feeding strategies (Jazdzewski et al. 1996; Dauby et al. in press; De ... [more ▼]

Within the Southern Ocean, amphipods have achieved a conspicuous adaptative radiation which gave rise to the development of numerous feeding strategies (Jazdzewski et al. 1996; Dauby et al. in press; De Broyer et al. in press). The discrepancy between the ecological significance of amphipods in the Antarctic and our poor knowledge of their ecofunctional role calls for a more detailed investigation of their importance in this ecosystem trophodynamics. This study focused on the eight amphipods species which were collected and from which isotopic and lipidic (when available) (Graeve et al. in press) compositions were compared to their respective gut contents previously described (Dauby et al. in press). The interest of both first techniques rely upon the direct relationship between the isotopic signatures and the lipid composition of organisms and those of their diet (De Niro and Epstein 1978, 1981; Peterson and Fry 1987; Graeve et al. 1994; Cripps et al 1999). Amphipod stable isotope ratios and fatty acids composition correspond rather accurately to the trophic classification based on gut contents and attest to their high spectrum of feeding types. Since the fundamental difference between the approaches to diet studies is the time scale each method addresses, this coincidence indicates that there would be no significant changes in feeding strategies over time. Three levels of the food web are covered by the eight species and, instead of belonging strictly to one trophic category, amphipods display a continuum of values from the suspension-feeder to scavengers. [less ▲]

Detailed reference viewed: 21 (0 ULg)