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See detailCarbonate chemistry in the coastal zone responds more strongly to eutrophication than to ocean acidification
Borges, Alberto ULg; Gypens, N.

in Limnology & Oceanography (2010), 55(1), 346-353

The accumulation of anthropogenic CO2 in the ocean has altered carbonate chemistry in surface waters since preindustrial times and is expected to continue to do so in the coming centuries. Changes in ... [more ▼]

The accumulation of anthropogenic CO2 in the ocean has altered carbonate chemistry in surface waters since preindustrial times and is expected to continue to do so in the coming centuries. Changes in carbonate chemistry can modify the rates and fates of marine primary production and calcification. These modifications can in turn lead to feedback on increasing atmospheric CO2. We show, using a numerical model, that in highly productive nearshore coastal marine environments, the effect of eutrophication on carbon cycling can counter the effect of ocean acidification on the carbonate chemistry of surface waters. Also, changes in river nutrient delivery due to management regulation policies can lead to stronger changes in carbonate chemistry than ocean acidification. Whether antagonistic or synergistic, the response of carbonate chemistry to changes of nutrient delivery to the coastal zone (increase or decrease, respectively) is stronger than ocean acidification. [less ▲]

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See detailCarbonate dissolution in the turbid and eutrophic Loire estuary
Abril, Gwenaël; Etcheber, Henri; Delille, Bruno ULg et al

in Marine Ecology. Progress Series (2003), 259

We measured particulate and dissolved organic carbon (POC and DOC), chlorophyll, oxygen, partial pressure of Co-2, pH, total alkalinity (TAlk) and particulate inorganic carbon (PIC) during a late summer ... [more ▼]

We measured particulate and dissolved organic carbon (POC and DOC), chlorophyll, oxygen, partial pressure of Co-2, pH, total alkalinity (TAlk) and particulate inorganic carbon (PIC) during a late summer cruise in the eutrophic Loire estuary. These parameters reveal an intense mineralisation of organic matter in the estuarine maximum turbidity zone (MTZ) that results in oxygen deficits (down to 20% of the saturation level) and high CO2 oversaturations (pCO(2) up to 2900 muatm). Several facts revealed the occurrence of carbonate dissolution in the Loire MTZ: large amounts of alkalinity were produced in the upper estuary, increasing its transfer to the ocean by 30%; the calculated saturation index showed a net undersaturation for aragonite and a slight undersaturation for calcite in the MTZ; and PIC decreased from 2.1% (% dry weight) in riverine suspension to 0.4% in the MTZ. A stoichiometric approach is used to assess the coupling between aerobic respiration and carbonate dissolution, where apparent oxygen utilisation, excess CO2, TAlk and dissolved inorganic carbon are compared quantitatively. About 20%, of the CO2 generated by respiration was involved in carbonate dissolution. The loss of PIC at the river-estuary transition quantitatively corresponds to the amount of authigenic calcite precipitated upstream in the highly eutrophic river. This suggests that CO2 exchange with the atmosphere along the eutrophic river-estuary continuum is buffered by carbonate precipitation in the autotrophic river and its dissolution in the heterotrophic estuary. [less ▲]

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See detailCarbonate Mounds: from Paradox to World Heritage
Henriet, Jean-Pierre; Hamoumi, N.; Da Silva, Anne-Christine ULg et al

in Marine Geology (2014), 352

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See detailThe carbonate system in the North Sea: sensitivity and model validation
Artioli, Y.; Blackford, J.C.; Butenschön, M. et al

in Journal of Marine Systems (2012), 102-104

The ocean plays an important role in regulating the climate, acting as a sink for carbon dioxide, perturbing the carbonate system and resulting in a slow decrease of seawater pH. Understanding the ... [more ▼]

The ocean plays an important role in regulating the climate, acting as a sink for carbon dioxide, perturbing the carbonate system and resulting in a slow decrease of seawater pH. Understanding the dynamics of the carbonate system in shelf sea regions is necessary to evaluate the impact of Ocean Acidification (OA) in these societally important ecosystems. Complex hydrodynamic and ecosystem coupled models provide a method of capturing the significant heterogeneity of these areas. However rigorous validation is essential to properly assess the reliability of such models. The coupled model POLCOMS–ERSEM has been implemented in the North Western European shelf with a new parameterization for alkalinity explicitly accounting for riverine inputs and the influence of biological processes. The model has been validated in a like with like comparison with North Sea data from the CANOBA dataset. The model shows good to reasonable agreement for the principal variables, physical (temperature and salinity), biogeochemical nutrients) and carbonate system (dissolved inorganic carbon and total alkalinity), but simulation of the erived variables, pH and pCO2, are not yet fully satisfactory. This high uncertainty is attributed mostly o riverine forcing and primary production. This study suggests that the model is a useful tool to provide information on Ocean Acidification scenarios, but uncertainty on pH and pCO2 needs to be reduced, particularly when impacts of OA on ecosystem functions are included in the model systems. [less ▲]

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See detailCarbonate system in the water masses of the Southeast Atlantic sector of the Southern Ocean during February and March 2008
Gonzalez-Davila, M.; Santana-Casiano, J. M.; Fine, R. A. et al

in Biogeosciences (2011), 8

Carbonate system variables were measured in the South Atlantic sector of the Southern Ocean along a transect from South Africa to the southern limit of the Antarctic Circumpolar Current (ACC) from ... [more ▼]

Carbonate system variables were measured in the South Atlantic sector of the Southern Ocean along a transect from South Africa to the southern limit of the Antarctic Circumpolar Current (ACC) from February to March 2008. Eddies detached from the retroflection of the Agulhas Current increased the gradients observed along the fronts. Minima in the fugacity of CO2, fCO2, and maxima in pH on either side of the frontal zone were observed, noting that within the frontal zone fCO2 reached maximum values and pH was at a minimum. Vertical distributions of water masses were described by their carbonate system properties and their relationship to CFC concentrations. Upper Circumpolar Deep Water (UCDW) and Lower Circumpolar Deep Water (LCDW) offered pHT,25 values of 7.56 and 7.61, respectively. The UCDW also had higher concentrations of CFC-12 (>0.2 pmol kg−1) as compared to deeper waters, revealing that UCDW was mixed with recently ventilated waters. Calcite and aragonite saturation states (Ω) were also affected by the presence of these two water masses with high carbonate concentrations. The aragonite saturation horizon was observed at 1000 m in the subtropical area and north of the Subantarctic Front. At the position of the Polar Front, and under the influence of UCDW and LCDW, the aragonite saturation horizon deepened from 800 m to 1500 m at 50.37° S, and reached 700 m south of 57.5° S. High latitudes proved to be the most sensitive areas to predicted anthropogenic carbon increase. Buffer coefficients related to changes in [CO2], [H+] and Ω with changes in dissolved inorganic carbon (CT) and total alkalinity (AT) offered minima values in the Antarctic Intermediate Water and UCDW layers. These coefficients suggest that a small increase in CT will sharply decrease the status of pH and carbonate saturation. Here we present data that suggest that south of 55° S, surface water will be under-saturated with respect to aragonite within the next few decades. [less ▲]

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See detailCarbonated concrete blocks for CO2 captation
Courard, Luc ULg; Parmentier, Véronique; Michel, Frédéric ULg

in Materialy Budowlane (2015), 10

The CO2 captation process called carbonation, improves specific properties of the concrete during the conversion of carbon dioxide CO2 into calcium carbonate CaCO3. Current environmental concerns motivate ... [more ▼]

The CO2 captation process called carbonation, improves specific properties of the concrete during the conversion of carbon dioxide CO2 into calcium carbonate CaCO3. Current environmental concerns motivate the study of carbonation in order to maximize the absorption of carbon dioxide. Moreover, lightweight concrete with bio-based products knows an interesting development in the construction field, especially as thermal insulation panels for walls in buildings. Concrete blocks produced with miscanthus mineralized aggregates offer interesting mechanical properties and minimal environmental impact. [less ▲]

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See detailCarbonates
Fredericq, Léon ULg

in Richet, Charles (Ed.) Dictionnaire de physiologie. 003. Tome III (1898)

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See detailCarbone
Fredericq, Léon ULg

in Richet, Charles (Ed.) Dictionnaire de physiologie. 003. Tome III (1898)

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See detailCarbone (oxyde de)
Fredericq, Léon ULg

in Richet, Charles (Ed.) Dictionnaire de physiologie. 003. Tome III (1898)

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See detailCarbonic anhydrase inhibitors: Synthesis and inhibition of the human carbonic anhydrase isoforms I, II, IX and XII with benzene sulfonamides incorporating 4- and 3-nitrophthalimide moieties
Sethi, Kalyan; Verma, Saurabh; Tanç, Muhammet et al

in Bioorganic & Medicinal Chemistry (2014), 22

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See detailCarbonic Anhydrase Ix, Mn/Ca Ix: Structure, Function And Involvement In Carcinogenesis
Pastorekova, S.; Kaluz, S.; Gibadulinova, A. et al

in Chemical Papers-Chemicke Zvesti (1998), 52

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See detailCarboniferous miospores of Western Europe: illustration and zonation.
Clayton, G; Coquel, R; Doubinger, J et al

in Mededelingen - Rijks Geologische Dienst (1977), 29

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See detailCarbonique (anhydride ou acide)
Fredericq, Léon ULg

in Richet, Charles (Ed.) Dictionnaire de physiologie. 003. Tome III (1898)

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See detailCarbonyl fluoride (COF2) vertical information above Jungfraujoch by FTIR and multi-spectra fitting: error budget and comparisons with KASIMA 3-D CTM model calculations
Duchatelet, Pierre ULg; Mahieu, Emmanuel ULg; Ruhnke, Roland et al

Poster (2008, April)

The major sources of fluorine in the stratosphere are CFC-11 and CFC-12. During the decomposition process, fluorine is first present in the form of carbonyl compounds (e.g. carbonyl fluoride (COF2 ... [more ▼]

The major sources of fluorine in the stratosphere are CFC-11 and CFC-12. During the decomposition process, fluorine is first present in the form of carbonyl compounds (e.g. carbonyl fluoride (COF2)). Given its long life time, COF2 is the second most abundant stratospheric fluorine reservoir. Earliest, COF2 vertical distributions were derived from occultation measurements performed by the ATMOS instrument during the SPACELAB-3 Space Shuttle mission in 1985. The Canadian FTIR spectrometer ACE-FTS, onboard the SCISAT-1 satellite, is the first instrument since the last ATMOS flight in 1994, to record COF2 vertical profiles from space. Four years of ACE-FTS occultation measurements are presently available. Several COF2 IR absorption lines located either in the so-called InSb (1-5 µm) and MCT (2-16 µm) spectral ranges can be used to determine its total column from ground-based high-resolution FTIR observations. In addition, we have proposed, during the EGU General Assembly 2007, an original retrieval procedure that allows us to derive information on the COF2 vertical distribution, between 17 and 30 km, from ground-based FTIR spectra recorded at Jungfraujoch. This “multi-microwindows multi-spectra” approach, using the SFIT-2 v3.91 algorithm, has been completely characterized in terms of fitting strategy and information content. Some examples of COF2 vertical profiles inversions were also presented. This year, we will complete the characterization of the multi-microwindows multi-spectra fitting procedure by exposing the full error budget affecting our COF2 partial and total columns products. Also, comparisons with COF2 model runs generated by the 3D CTM KASIMA (KArlsruhe SImulation model of the Middle Atmosphere) will be presented and critically discussed. [less ▲]

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See detailCarcasses of Belgian Blue double muscle culled cows or growing fattening bulls: essential fatty acids content in 17 meat pieces
Robaye, Vincent ULg; Dotreppe, Olivier ULg; Cabaraux, Jean-François ULg et al

in book of abstract of the 59th Annual meeting of the European Association for Animal Production (2008)

Detailed reference viewed: 43 (6 ULg)