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7. Sea Ice CO 2 Dynamics Across Seasons: Impact of Processes at the Interfaces

Author

Van der Linden, F. C., primary, Tison, J.‐L., additional, Champenois, W., additional, Moreau, S., additional, Carnat, G., additional, Kotovitch, M., additional, Fripiat, F., additional, Deman, F., additional, Roukaerts, A., additional, Dehairs, F., additional, Wauthy, S., additional, Lourenço, A., additional, Vivier, F., additional, Haskell, T., additional, and Delille, B., additional

Published
2020
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8. Sea Ice CO2 Dynamics Across Seasons: Impact of Processes at the Interfaces

Author

Van Der Linden, Fanny, Tison, Jean-Louis, Champenois, W., Moreau, Sébastien, Carnat, Gauthier, Kotovitch, Marie, Fripiat, François, Deman, Florian, Roukaerts, Arnout, Dehairs, F., Wauthy, Sarah, Lourenço, A., Vivier, Frédéric, Haskell, T.G., Delille, B., Van Der Linden, Fanny, Tison, Jean-Louis, Champenois, W., Moreau, Sébastien, Carnat, Gauthier, Kotovitch, Marie, Fripiat, François, Deman, Florian, Roukaerts, Arnout, Dehairs, F., Wauthy, Sarah, Lourenço, A., Vivier, Frédéric, Haskell, T.G., and Delille, B.

Abstract

Winter to summer CO2 dynamics within landfast sea ice in McMurdo Sound (Antarctica) were investigated using bulk ice pCO2 measurements, air-snow-ice CO2 fluxes, dissolved inorganic carbon (DIC), total alkalinity (TA), and ikaite saturation state. Our results suggest depth-dependent biotic and abiotic controls that led us to discriminate the ice column in three layers. At the surface, winter pCO2 supersaturation drove CO2 release to the atmosphere while spring-summer pCO2 undersaturation led to CO2 uptake most of the time. CO2 fluxes showed a diel pattern superimposed upon this seasonal pattern which was potentially assigned to either ice skin freeze-thaw cycles or diel changes in net community production. In the ice interior, the pCO2 decrease across the season was driven by physical processes, mainly independent of the autotrophic and heterotrophic phases. Bottom sea ice was characterized by a massive biomass build-up counterintuitively associated with transient heterotrophic activity and nitrate plus nitrite accumulation. This inconsistency is likely related to the formation of a biofilm. This biofilm hosts both autotrophic and heterotrophic activities at the bottom of the ice during spring and may promote calcium carbonate precipitation., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2020

11. Sea Ice CO2 Dynamics Across Seasons: Impact of Processes at the Interfaces.

Author

Van der Linden, F. C., Tison, J. -L., Champenois, W., Moreau, S., Carnat, G., Kotovitch, M., Fripiat, F., Deman, F., Roukaerts, A., Dehairs, F., Wauthy, S., Lourenço, A., Vivier, F., Haskell, T., and Delille, B.

Subjects
SEA ice, OCEAN dynamics, OCEANOGRAPHY, PHYTOPLANKTON, FLUX (Energy)
Abstract

Winter to summer CO2 dynamics within landfast sea ice in McMurdo Sound (Antarctica) were investigated using bulk ice pCO2 measurements, air-snow-ice CO2 fluxes, dissolved inorganic carbon (DIC), total alkalinity (TA), and ikaite saturation state. Our results suggest depth-dependent biotic and abiotic controls that led us to discriminate the ice column in three layers. At the surface, winter pCO2 supersaturation drove CO2 release to the atmosphere while spring-summer pCO2 undersaturation led to CO2 uptake most of the time. CO2 fluxes showed a diel pattern superimposed upon this seasonal pattern which was potentially assigned to either ice skin freeze-thaw cycles or diel changes in net community production. In the ice interior, the pCO2 decrease across the season was driven by physical processes, mainly independent of the autotrophic and heterotrophic phases. Bottom sea ice was characterized by a massive biomass build-up counterintuitively associated with transient heterotrophic activity and nitrate plus nitrite accumulation. This inconsistency is likely related to the formation of a biofilm. This biofilm hosts both autotrophic and heterotrophic activities at the bottom of the ice during spring and may promote calcium carbonate precipitation. [ABSTRACT FROM AUTHOR]

Published
2020
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14. Antarctic sea ice trophic status

Author

Van der Linden, F., Champenois, W., Heinesch, B., Moreau, S., Kotovitch, M., Carnat, G., Fripiat, F., Zhou, J., Haskell, T., Tison, J.-L., and Delille, B.

Published
2017

17. Temperature, productivity and sediment characteristics as drivers of seasonal and spatial variations of dissolved methane in the near-shore coastal areas (Belgian coastal zone, North Sea)

Author

EGU General Assembly 2017 (23–28 April 2017: Vienna (Austria)), Borges, Alberto V, Speeckaert, Gaelle, Champenois, W., Scranton, Mary I, Gypens, Nathalie, EGU General Assembly 2017 (23–28 April 2017: Vienna (Austria)), Borges, Alberto V, Speeckaert, Gaelle, Champenois, W., Scranton, Mary I, and Gypens, Nathalie

Abstract

0, info:eu-repo/semantics/nonPublished

Published
2017

18. Acoustic monitoring of O2 production of a seagrass meadow

Author

Felisberto, P., Jesus, M, Zabel, F, Santos, R, Silva, J, Gobert, S., Beer, S., Bjork, M., Mazzuca, S., Procaccini, G, Runcie, W, Champenois, W., and Borges, A.V.

Subjects
Posidonia oceanica [Neptune grass]
Abstract

Acoustic data were acquired in October 2011 over a Posidonia oceanica meadow in the Bay of la Revellata, Calvi, Corsica. The purpose was to develop an acoustic system for monitoring the oxygen (O2) production of an entire seagrass meadow. In a shallow water area < 38 m), densely covered by P. oceanica, a sound source transmitted signals in 3 different bands (400–800 Hz, 1.5–3.5 kHz and 6.5–8.5 kHz) toward three self-recording hydrophones at a distance of 100 m, over the period of one week. The data show a high correlation between the diel cycle of the acoustic signals' energy received by the hydrophones and the temporal changes in water column O2 concentration as measured by optodes. The results thus show that a simple acoustic acquisition system can be used to monitor the O2-based productivity of a seagrass meadow at the ecosystem level with high temporal resolution. The finding of a significant production of O2 as bubbles in seagrass ecosystems suggests that net primary production is underestimated by methods that rely on the mass balance of dissolved O2 measurements.

Published
2015

19. BIGSOUTH, Biogeochemical Cycles in the Southern Ocean: Role within the Earth System

Author

Dehairs, F., Tison, J.-L., Delille, B., André, L., Goosse, H., Fripiat, F., Moreau, S., Cavagna, A.-J., Vancoppenolle, M., Schoemann, V., Sapart, C., Heinesch, B., Zhou, J., Carnat, G., Roukaert, A., Champenois, W., de Jong, J., Scheikunde, Analytische en Milieu Chemie, Wetenschappen van het Systeem Aarde, and Analytisch- Milieu- & Geo-Chemie

Published
2014

21. Methane dynamics in the Belgian coastal zone, a contribution to the BELSPO project “4 decades of Belgian marine monitoring” (4Demon)

Author

North Sea Open Science Conference 2016 (7-10 November 2016: Ostende), Borges, Alberto V, Champenois, W., Gypens, Nathalie, Delille, B., Harlay, Jérôme, Ruddick, Kevin, Nechad, Bouchra, Vandenberghe, Thomas, Strobbe, Francis, De Cauwer, Karien, Lagring, Ruth, North Sea Open Science Conference 2016 (7-10 November 2016: Ostende), Borges, Alberto V, Champenois, W., Gypens, Nathalie, Delille, B., Harlay, Jérôme, Ruddick, Kevin, Nechad, Bouchra, Vandenberghe, Thomas, Strobbe, Francis, De Cauwer, Karien, and Lagring, Ruth

Abstract

info:eu-repo/semantics/nonPublished

Published
2016

22. Correlation between the acoustic noise field measured in a Posidonia oceanica bed and the photosynthetic activity

Author

Felisberto, P., Zabel, F., Rodríguez, O. C., Santos, P., Jesus, S. M., Champenois, W., Borges, A. V., and Santos, Rui

Abstract

During the period of one week, from May 8 to 15, 2013, acoustic data was gathered at three locations over a Posidonia oceanica bed in the Bay of Revellata, Corsica. Preliminary analysis of the acoustic data shows that the environmental noise field in the band 2-7kHz was dominant during the period. The noise in this band is generally associated with wind and surface agitation. However, the noise power was not significantly correlated with wind speed. On the contrary, the diel cycle of the noise power at three locations was highly correlated with the water column concentration of O2, as measured by optodes. These measurements of environmental noise have confirmed the correlation between active acoustic signals transmitted along a seagrass meadow and the photosynthetic activity of the plants observed in a previous experiment conducted in the same area .The results suggest that acoustic noise can be used as a proxy for the photosynthetic oxygen production of a Posidonia oceanica meadow. Therefore, this work is a contribution for the development of a low cost passive acoustic system to assess the primary production of coastal ecosystems .

Published
2014

25. Year Round survey of Ocean-Sea Ice-Air Exchanges – the YROSIAE survey

Author

International Symposium on Sea Ice in a Changing Environment (10-14 mars 2014: Hobart), Delille, Bruno, Haskell, T.G., Champenois, W., Heinesch, B., Zhou, Jiayun, Schoemann, Véronique, Carnat, Gauthier, Fripiat, François, Goossens, Thomas, Moreau, Sébastien, Vancoppenolle, Martin, Viviers, F, Laurenço, A, Tison, Jean-Louis, International Symposium on Sea Ice in a Changing Environment (10-14 mars 2014: Hobart), Delille, Bruno, Haskell, T.G., Champenois, W., Heinesch, B., Zhou, Jiayun, Schoemann, Véronique, Carnat, Gauthier, Fripiat, François, Goossens, Thomas, Moreau, Sébastien, Vancoppenolle, Martin, Viviers, F, Laurenço, A, and Tison, Jean-Louis

Abstract

info:eu-repo/semantics/nonPublished

Published
2014

26. Establishing research strategies, methodologies and technologies to link genomics and proteomics to seagrass productivity, community metabolism, and ecosystem carbon fluxes

Author

Mazzuca, Silvia, Björk, Mats, Beer, S., Felisberto, P., Gobert, S., Procaccini, G., Runcie, J., Silva, J., Borges, A. V., Brunet, C., Buapet, Pimchanok, Champenois, W., Costa, M. M., D'Esposito, D., Gullström, Martin, Lejeune, P., Lepoint, G., Olive, I., Rasmusson, Lina M., Richir, J., Ruocco, M., Serra, I. A., Spadafora, A., Santos, Rui, Mazzuca, Silvia, Björk, Mats, Beer, S., Felisberto, P., Gobert, S., Procaccini, G., Runcie, J., Silva, J., Borges, A. V., Brunet, C., Buapet, Pimchanok, Champenois, W., Costa, M. M., D'Esposito, D., Gullström, Martin, Lejeune, P., Lepoint, G., Olive, I., Rasmusson, Lina M., Richir, J., Ruocco, M., Serra, I. A., Spadafora, A., and Santos, Rui

Abstract

A complete understanding of the mechanistic basis of marine ecosystem functioning is only possible through integrative and interdisciplinary research. This enables the prediction of change and possibly the mitigation of the consequences of anthropogenic impacts. One major aim of the European Cooperation in Science and Technology (COST) Action ES0609 Seagrasses productivity. From genes to ecosystem management, is the calibration and synthesis of various methods and the development of innovative techniques and protocols for studying seagrass ecosystems. During 10 days, 20 researchers representing a range of disciplines (molecular biology, physiology, botany, ecology, oceanography, and underwater acoustics) gathered at The Station de Recherches Sous-marines et Oceanographiques (STARESO, Corsica) to study together the nearby Posidonia oceanica meadow. STARESO is located in an oligotrophic area classified as pristine site where environmental disturbances caused by anthropogenic pressure are exceptionally low. The healthy P. oceanica meadow, which grows in front of the research station, colonizes the sea bottom from the surface to 37 m depth. During the study, genomic and proteomic approaches were integrated with ecophysiological and physical approaches with the aim of understanding changes in seagrass productivity and metabolism at different depths and along daily cycles. In this paper we report details on the approaches utilized and we forecast the potential of the data that will come from this synergistic approach not only for P. oceanica but for seagrasses in general., AuthorCount:24

Published
2013
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27. Fluxes of dimethylsulfide from warming sea ice

Author

SOLAS Open Science Conference (Washington State, USA), Carnat, Gauthier, Zhou, Jiayun, Papakyriakou, Tim, Delille, Bruno, Schoemann, Véronique, Champenois, W., Fripiat, François, Haskell, T.G., Tison, Jean-Louis, SOLAS Open Science Conference (Washington State, USA), Carnat, Gauthier, Zhou, Jiayun, Papakyriakou, Tim, Delille, Bruno, Schoemann, Véronique, Champenois, W., Fripiat, François, Haskell, T.G., and Tison, Jean-Louis

Abstract

info:eu-repo/semantics/nonPublished

Published
2012

28. Lake Kivu: Limnology and biogeochemistry of a tropical great lake

Author

Borges, Alberto Vieira, Bouillon, Steven, Abril, G., Delille, B., Poirier, D., Commarieu, M.V., Lepoint, G., Morana, C., Champenois, W., Servais, Pierre, Descy, Jean Pierre, Darchambeau, F., Borges, Alberto Vieira, Bouillon, Steven, Abril, G., Delille, B., Poirier, D., Commarieu, M.V., Lepoint, G., Morana, C., Champenois, W., Servais, Pierre, Descy, Jean Pierre, and Darchambeau, F.

Abstract

We report a dataset of the partial pressure of CO2 (pCO2) and methane concentrations (CH4) in the surface waters of Lake Kivu obtained during four cruises covering the two main seasons (rainy and dry). Spatial gradients of surface pCO2 and CH4 concentrations were modest in the main basin. In Kabuno Bay, pCO2 and CH4 concentrations in surface waters were higher, owing to the stronger influence of subaquatic springs from depth. Seasonal variations of pCO2 and CH4 in the main basin of Lake Kivu were strongly driven by deepening of the epilimnion and the resulting entrainment of water characterized by higher pCO2 and CH4 concentrations. Physical and chemical vertical patterns in Kabuno Bay were seasonally stable, owing to a stronger stratification and smaller surface area inducing fetch limitation of wind driven turbulence. A global and regional cross-system comparison of pCO2 and CH4 concentrations in surface waters of lakes highlights the peculiarity of Kabuno Bay in terms of pCO2 values in surface waters. In terms of surface CH4 concentrations, both Kabuno Bay and the main basin of Lake Kivu are at the lower end of values in lakes globally, despite the huge amounts of CH4 and CO2 in the deeper layers of the lake., info:eu-repo/semantics/published

Published
2012

29. Establishing Research Strategies, Methodologies and Technologies to Link Genomics and Proteomics to Seagrass Productivity, Community Metabolism, and Ecosystem Carbon Fluxes

Author

Mazzuca, Silvia, primary, Björk, M., additional, Beer, S., additional, Felisberto, P., additional, Gobert, S., additional, Procaccini, G., additional, Runcie, J., additional, Silva, J., additional, Borges, A. V., additional, Brunet, C., additional, Buapet, P., additional, Champenois, W., additional, Costa, M. M., additional, D’Esposito, D., additional, Gullström, M., additional, Lejeune, P., additional, Lepoint, G., additional, Olivé, I., additional, Rasmusson, L. M., additional, Richir, J., additional, Ruocco, M., additional, Serra, I. A., additional, Spadafora, A., additional, and Santos, Rui, additional

Published
2013
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30. Sea Ice CO2Dynamics Across Seasons: Impact of Processes at the Interfaces

Author

Van der Linden, F. C., Tison, J.‐L., Champenois, W., Moreau, S., Carnat, G., Kotovitch, M., Fripiat, F., Deman, F., Roukaerts, A., Dehairs, F., Wauthy, S., Lourenço, A., Vivier, F., Haskell, T., and Delille, B.

Abstract

Winter to summer CO2dynamics within landfast sea ice in McMurdo Sound (Antarctica) were investigated using bulk ice pCO2measurements, air‐snow‐ice CO2fluxes, dissolved inorganic carbon (DIC), total alkalinity (TA), and ikaite saturation state. Our results suggest depth‐dependent biotic and abiotic controls that led us to discriminate the ice column in three layers. At the surface, winter pCO2supersaturation drove CO2release to the atmosphere while spring‐summer pCO2undersaturation led to CO2uptake most of the time. CO2fluxes showed a diel pattern superimposed upon this seasonal pattern which was potentially assigned to either ice skin freeze‐thaw cycles or diel changes in net community production. In the ice interior, the pCO2decrease across the season was driven by physical processes, mainly independent of the autotrophic and heterotrophic phases. Bottom sea ice was characterized by a massive biomass build‐up counterintuitively associated with transient heterotrophic activity and nitrate plus nitrite accumulation. This inconsistency is likely related to the formation of a biofilm. This biofilm hosts both autotrophic and heterotrophic activities at the bottom of the ice during spring and may promote calcium carbonate precipitation. Sea ice participates actively in the regional cycling of CO2both as a source and a sink at different times of the year depending on ice physics, ice chemistry, and ice trophic status (autotrophic vs. heterotrophic). We identified the key processes driving the CO2dynamics in each sea ice layer (surface, interior, and bottom) from McMurdo Sound (Antarctica) from late winter to summer. At the surface, CO2release from the ice to the atmosphere occurred in late winter while CO2uptake occurred in summer. Superimposed upon this seasonal pattern, we observed a diurnal pattern with both release and uptake occurring over 24 hr period. This diurnal pattern can be related to physical processes (nocturnal freeze‐up and diurnal melting) or biotic processes (autotrophy or heterotrophy). In the ice interior, a succession of autotrophic and heterotrophic phases took place. At the sea ice bottom, a particular assemblage of microbial cells and organic matter, called biofilm, enabled the accumulation of biomass and nitrate plus nitrite simultaneously leading to both autotrophic and heterotrophic activities. In addition, this biofilm is suggested to promote calcium carbonate precipitation. First long‐term monitoring of both pCO2and CO2fluxes at sea ice interfaces in McMurdo Sound (Antarctica) from late winter to summerLarge biomass build‐up is strikingly associated with transient heterotrophy and nitrate plus nitrite accumulationNew conceptual approach involving biofilm formation can explain observed inconsistencies: accumulation of nitrate plus nitrite and CaCO3

Published
2020
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32. Annual cycle of dimethylsulfoniopropionate (DMSP) and dimethylsulfoxide (DMSO) related to phytoplankton succession in the Southern North Sea.

Author

Speeckaert G, Borges AV, Champenois W, Royer C, and Gypens N

Subjects
Belgium, Chlorophyll, Chlorophyll A, Diatoms, Estuaries, Haptophyta, North Sea, Seasons, Spatial Analysis, Dimethyl Sulfoxide analysis, Phytoplankton, Seawater analysis, Sulfonium Compounds analysis
Abstract

The influence of abiotic and biotic variables on the concentration of dimethyl sulfide (DMS), dimethylsulfoniopropionate (DMSP), and dimethylsulfoxide (DMSO), were investigated during an annual cycle in 2016 in the Belgian Coastal Zone (BCZ, North Sea). We reported strong seasonal variations in the concentration of these compounds linked to the phytoplankton succession with high DMS(P,O) producers (mainly Phaeocystis globosa) occurring in spring and low DMS(P,O) producers (various diatoms species) occurring in early spring and autumn. Spatial gradients of DMS and DMSP were related to those of phytoplankton biomass itself related to the inputs of nutrients from the Scheldt estuary. However, the use of a relationship with Chlorophyll-a (Chl-a) concentration is not sufficient to predict DMSP. Accounting for the phytoplankton composition, two different DMSP versus Chl-a correlations could be established, one for diatoms and another one for Phaeocystis colonies. We also reported high nearshore DMSO concentrations uncoupled to Chl-a and DMSP concentrations but linked to high suspended particulate matter (SPM) presumably coming from the Scheldt estuary as indicated by the positive relationship between annual average SPM and salinity., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Published
2018
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33. Massive marine methane emissions from near-shore shallow coastal areas.

Author

Borges AV, Champenois W, Gypens N, Delille B, and Harlay J

Abstract

Methane is the second most important greenhouse gas contributing to climate warming. The open ocean is a minor source of methane to the atmosphere. We report intense methane emissions from the near-shore southern region of the North Sea characterized by the presence of extensive areas with gassy sediments. The average flux intensities (~130 μmol m(-2) d(-1)) are one order of magnitude higher than values characteristic of continental shelves (~30 μmol m(-2) d(-1)) and three orders of magnitude higher than values characteristic of the open ocean (~0.4 μmol m(-2) d(-1)). The high methane concentrations (up to 1,128 nmol L(-1)) that sustain these fluxes are related to the shallow and well-mixed water column that allows an efficient transfer of methane from the seafloor to surface waters. This differs from deeper and stratified seep areas where there is a large decrease of methane between bottom and surface by microbial oxidation or physical transport. Shallow well-mixed continental shelves represent about 33% of the total continental shelf area, so that marine coastal methane emissions are probably under-estimated. Near-shore and shallow seep areas are hot spots of methane emission, and our data also suggest that emissions could increase in response to warming of surface waters.

Published
2016
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