Search results for "aragonite"

showing 10 items of 90 documents

Seagrass ecosystem response to long-term high CO2 in a Mediterranean volcanic vent

2014

We examined the long-term effect of naturally acidified water on a Cymodocea nodosa meadow growing at a shallow volcanic CO2 vent in Vulcano Island (Italy). Seagrass and adjacent unvegetated habitats growing at a low pH station (pH = 7.65 ± 0.02) were compared with corresponding habitats at a control station (pH = 8.01 ± 0.01). Density and biomass showed a clear decreasing trend at the low pH station and the below- to above-ground biomass ratio was more than 10 times lower compared to the control. C content and delta 13C of leaves and epiphytes were significantly lower at the low pH station. Photosynthetic activity of C. nodosa was stimulated by low pH as seen by the significant increase in…

Ocean Acidification International Coordination Centre (OA-ICC)TemperateSalinityChlorophyll ainorganicAlkalinityLight saturation point standard errorPhotosynthetic quantum efficiencyMediterranean Sea Acidification in a Changing Climate MedSeATemperature waterCarbon inorganic dissolvedCalculated using seacarb after Nisumaa et al 2010IrradianceRespiration rate carbonAragonite saturation stateBiomassAlkalinity totalIrradiance standard errortotalCO2 ventCymodocea nodosapHRespirationEpiphytes loadMaximum photochemical quantum yield of photosystem II standard errorNet community production of carbonTemperaturePartial pressure of carbon dioxide (water) at sea surface temperature (wet air) standard errordissolvedRespiration rate carbon standard errorCarbonate ionMaximum photochemical quantum yield of photosystem IIPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)Net community production of carbon standard errorIlluminance standard errorSoft bottom communitystandard errorCarbon inorganic dissolved standard errorRespiration rateElectron transport rate standard errorEarth System Researchδ13CPhotosynthetic quantum efficiency standard errorField observationChlorophyll a standard errorGross primary production of carbonBiomass standard errorCalcium carbonatePotentiometric titrationCalcite saturation stateShoot densityPotentiometricwaterIlluminanceOxygen standard errorBenthosAlkalinity total standard errorMediterranean Sea Acidification in a Changing Climate (MedSeA)Electron transport rateLight saturation pointOcean Acidification International Coordination Centre OA ICCMediterranean SeaGross primary production of carbon standard errorBicarbonate ionSoft-bottom communityδ13C standard errorTemperature water standard errorCalculated using seacarb after Nisumaa et al. (2010)Primary production PhotosynthesisSpeciespH standard errorCarbonate system computation flagloadPrimary production/PhotosynthesisFugacity of carbon dioxide (water) at sea surface temperature (wet air)CarbonBiomass/Abundance/Elemental compositionTreatmentEpiphytes load standard errorOxygenPartial pressure of carbon dioxide water at sea surface temperature wet airEpiphytes loadCarbon dioxideCarbon standard errorEntire communityFugacity of carbon dioxide water at sea surface temperature wet airGroupBiomass Abundance Elemental compositionCoast and continental shelfEpiphytesShoot density standard errorCalcium carbonate standard error
researchProduct

Seawater carbonate chemistry and coralline algal diversity

2021

Calcified coralline algae are ecologically important in rocky habitats in the marine photic zone worldwide and there is growing concern that ocean acidification will severely impact them. Laboratory studies of these algae in simulated ocean acidification conditions have revealed wide variability in growth, photosynthesis and calcification responses, making it difficult to assess their future biodiversity, abundance and contribution to ecosystem function. Here, we apply molecular systematic tools to assess the impact of natural gradients in seawater carbonate chemistry on the biodiversity of coralline algae in the Mediterranean and the NW Pacific, link this to their evolutionary history and …

Ocean Acidification International Coordination Centre (OA-ICC)TemperateSalinityCommunity composition and diversityBicarbonate ion standard deviationinorganicAlkalinity total standard deviationAlkalinityExperimentTemperature waterCarbon inorganic dissolvedCalculated using seacarb after Nisumaa et al 2010Aragonite saturation stateNorth PacificMarine habitatAlkalinity totaltotalCO2 ventpHTemperaturedissolvedCarbonate ionPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)Calcium carbonate standard deviationstandard errorEarth System Researchstandard deviationField observationCalcium carbonateCoverageCalcite saturation stateLocationwaterPartial pressure of carbon dioxideSiteRocky-shore communityCalcium carbonate massAragonite saturation state standard deviationBenthosSalinity standard deviationOcean Acidification International Coordination Centre OA ICCMediterranean SeaCarbon inorganic dissolved standard deviationCalcite saturation state standard deviationTypeBicarbonate ionCalculated using seacarb after Nisumaa et al. (2010)Coverage standard errorfungiEvent labelPartial pressure of carbon dioxide standard deviationCarbonate system computation flagpH standard deviationCarbonate ion standard deviationFugacity of carbon dioxide (water) at sea surface temperature (wet air)CarbonPartial pressure of carbon dioxide water at sea surface temperature wet airCarbon dioxideRocky shore communityEntire communityFugacity of carbon dioxide water at sea surface temperature wet airCoast and continental shelfSpecies richness
researchProduct

Decline in Coccolithophore Diversity and Impact on Coccolith Morphogenesis Along a Natural CO2 Gradient

2014

A natural pH gradient caused by marine CO2 seeps off Vulcano Island (Italy) was used to assess the effects of ocean acidification on coccolithophores, which are abundant planktonic unicellular calcifiers. Such seeps are used as natural laboratories to study the effects of ocean acidification on marine ecosystems, since they cause long-term changes in seawater carbonate chemistry and pH, exposing the organisms to elevated CO2 concentrations and therefore mimicking future scenarios. Previous work at CO2 seeps has focused exclusively on benthic organisms. Here we show progressive depletion of 27 coccolithophore species, in terms of cell concentrations and diversity, along a calcite saturation …

Ocean Acidification International Coordination Centre (OA-ICC)TemperateSalinityCommunity composition and diversityinorganicAlkalinityCoccospheres malformedMediterranean Sea Acidification in a Changing Climate MedSeATemperature waterCarbon inorganic dissolvedCalculated using seacarb after Nisumaa et al 2010Aragonite saturation stateAlkalinity totaltotalCO2 ventpHPelagosTemperaturedissolvedCarbonate ionPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)Earth System ResearchmalformedField observationPotentiometric titrationCalcite saturation stateCoccospheresPotentiometricwaterGrowth MorphologyMediterranean Sea Acidification in a Changing Climate (MedSeA)Ocean Acidification International Coordination Centre OA ICCMediterranean SeaBicarbonate ionCalculated using seacarb after Nisumaa et al. (2010)Calculated using CO2SYSfungiCarbonate system computation flagCoccospheres corrodedFugacity of carbon dioxide (water) at sea surface temperature (wet air)CarbonBiomass/Abundance/Elemental compositionPartial pressure of carbon dioxide water at sea surface temperature wet airSample IDCarbon dioxidecorrodedEntire communityGrowth/MorphologyPhytoplanktonFugacity of carbon dioxide water at sea surface temperature wet airBiomass Abundance Elemental compositionCoast and continental shelfNumber of species
researchProduct

Shallow water marine sediment bacterial community shifts along a natural CO2 gradient in the Mediterranean Sea Off vulcano, Italy

2014

The effects of increasing atmospheric CO(2) on ocean ecosystems are a major environmental concern, as rapid shoaling of the carbonate saturation horizon is exposing vast areas of marine sediments to corrosive waters worldwide. Natural CO(2) gradients off Vulcano, Italy, have revealed profound ecosystem changes along rocky shore habitats as carbonate saturation levels decrease, but no investigations have yet been made of the sedimentary habitat. Here, we sampled the upper 2 cm of volcanic sand in three zones, ambient (median pCO(2) 419 µatm, minimum Omega (arag) 3.77), moderately CO(2)-enriched (median pCO(2) 592 µatm, minimum Omega (arag) 2.96), and highly CO(2)-enriched (median pCO(2) 1611…

Ocean Acidification International Coordination Centre (OA-ICC)TemperateSalinityPotentiometric titrationCalcite saturation stateCommunity composition and diversityPotentiometricinorganicwaterAlkalinitySiteFigureBenthosTemperature waterCarbon inorganic dissolvedAbundanceCalculated using seacarb after Nisumaa et al 2010Ocean Acidification International Coordination Centre OA ICCMediterranean SeaBicarbonate ionAragonite saturation stateSoft-bottom communityAlkalinity totalLONGITUDEtotalCalculated using seacarb after Nisumaa et al. (2010)CO2 ventSpeciesShannon Diversity IndexpHCalculated using CO2SYSTemperatureCarbonate system computation flagdissolvedFugacity of carbon dioxide (water) at sea surface temperature (wet air)Carbonate ionCarbonPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)Partial pressure of carbon dioxide water at sea surface temperature wet airCarbon dioxideSoft bottom communityEntire communityEarth System ResearchLATITUDEFugacity of carbon dioxide water at sea surface temperature wet airGroupCoast and continental shelfField observationClass
researchProduct

Pmarg-pearlin is a matrix protein involved in nacre framework formation in the pearl oyster Pinctada margaritifera.

2011

11 pages; International audience; The shell of pearl oysters is organized in multiple layers of CaCO(3) crystallites packed together in an organic matrix. Relationships between the components of the organic matrix and mechanisms of nacre formation currently constitute the main focus of research into biomineralization. In this study, we characterized the pearlin protein from the oyster Pinctada margaritifera (Pmarg); this shares structural features with other members of a matrix protein family, N14/N16/pearlin. Pmarg pearlin exhibits calcium- and chitin-binding properties. Pmarg pearlin transcripts are distinctively localized in the mineralizing tissue responsible for nacre formation. More s…

OysterPteriidaeMolecular Sequence Dataengineering.materialBiologyMatrix (biology)010402 general chemistry01 natural sciencesBiochemistry03 medical and health sciencesProtein structureAnimal Shellsbiology.animalAnimalsAmino Acid SequencePinctadaRNA Messenger[SDV.IB.BIO]Life Sciences [q-bio]/Bioengineering/BiomaterialsMolecular Biologyglycoproteins030304 developmental biologyorganic matrix0303 health sciencesExtracellular Matrix ProteinsEcologyAragoniteOrganic ChemistryPinctada margaritiferabiology.organism_classificationbiomineralization[ SDV.IB.BIO ] Life Sciences [q-bio]/Bioengineering/Biomaterials0104 chemical sciencesCell biologyprotein structuresengineeringMolecular Medicinepearl oysterPearlBiomineralization
researchProduct

Are morphology and composition of gallstones related? An x-ray diffraction study

1994

Abstract An x-ray diffractometric technique was used to study the crystalline composition of gallstones removed during surgery from 106 patients. Monohydrate cholesterol was found in the stones of 70 (66%) patients, either alone (33%) or in association with calcium salts (33%). The anhydrous form of cholesterol was found in the stones of 28 (26%) patients, either alone (10%) or in association with calcium salts (16%). These salts (vaterite, aragonite, and calcite) were found in 50% of cases in varying amounts (from 12% to 15% of the stone weight). Eight stones contained no cholesterol: 4 showed an amorphous pattern and 4 were composed of calcium carbonate salts. In 7 of 8 patients with bile…

PharmacologyCalcitemedicine.medical_specialtyBile ductbusiness.industryCholesterolAragoniteGallstonesengineering.materialGallbladder Stonemedicine.diseaseSurgerychemistry.chemical_compoundmedicine.anatomical_structureCalcium carbonatechemistryVateriteengineeringmedicinePharmacology (medical)businessNuclear chemistryCurrent Therapeutic Research
researchProduct

Effects of ocean acidification on the shells of four Mediterranean gastropod species near a CO2 seep

2017

Marine CO2seeps allow the study of the long-term effects of elevated pCO2(ocean acidification) on marine invertebrate biomineralization. We investigated the effects of ocean acidification on shell composition and structure in four ecologically important species of Mediterranean gastropods (two limpets, a top-shell snail, and a whelk). Individuals were sampled from three sites near a volcanic CO2seep off Vulcano Island, Italy. The three sites represented ambient (8.15 pH), moderate (8.03 pH) and low (7.73 pH) seawater mean pH. Shell mineralogy, microstructure, and mechanical strength were examined in all four species. We found that the calcite/aragonite ratio could vary and increased signifi…

Settore BIO/07 - Ecologia0106 biological sciences010504 meteorology & atmospheric sciencesMediterraneanAquatic Scienceengineering.materialOceanography01 natural scienceschemistry.chemical_compoundWhelkCO2 seepShellGastropodMineral0105 earth and related environmental sciencesCalcitebiologyOcean acidification010604 marine biology & hydrobiologyLimpetAragoniteOcean acidificationMarine invertebratesbiology.organism_classificationPollutionPetroleum seepOceanographychemistryengineeringSeawaterGeologyMarine Pollution Bulletin
researchProduct

Effects of ocean acidification on embryonic respiration and development of a temperate wrasse living along a natural CO2 gradient

2016

Volcanic CO2 seeps provide opportunities to investigate the effects of ocean acidification on organisms in the wild. To understand the influence of increasing CO2 concentrations on the metabolic rate (oxygen consumption) and the development of ocellated wrasse early life stages, we ran two field experiments, collecting embryos from nesting sites with different partial pressures of CO2 [pCO2; ambient (400 µatm) and high (800-1000 µatm)] and reciprocally transplanting embryos from ambient- to high-CO2 sites for 30 h. Ocellated wrasse offspring brooded in different CO2 conditions had similar responses, but after transplanting portions of nests to the high-CO2 site, embryos from parents that sp…

StageOcean Acidification International Coordination Centre (OA-ICC)TemperateRegistration number of speciesSalinityinorganicYolk area standard errorAlkalinityExperimentTemperature waterCarbon inorganic dissolvedCalculated using seacarb after Nisumaa et al 2010Aragonite saturation stateRespiration rate oxygenChordataAlkalinity totaltotalCO2 ventpHPelagosReproductionRespirationSymphodus ocellatusTemperatureYolk areadissolvedCarbonate ionPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)Field experimentTemperature water standard deviationTime pointstandard errorRespiration rateEarth System Researchstandard deviationFOS: Medical biotechnologyUniform resource locator link to referenceTime point descriptiveHatchling lengthCalcite saturation statewaterPartial pressure of carbon dioxidedescriptiveGrowth MorphologyFigureUniform resource locator/link to referenceSalinity standard deviationOcean Acidification International Coordination Centre OA ICCMediterranean SeaAnimaliaEggs areaTypeBicarbonate ionNektonEggs area standard errorCalculated using seacarb after Nisumaa et al. (2010)SpeciesPartial pressure of carbon dioxide standard deviationCarbonate system computation flagpH standard deviationHatchling length standard errorFugacity of carbon dioxide (water) at sea surface temperature (wet air)CarbonTreatmentOxygenPartial pressure of carbon dioxide water at sea surface temperature wet airCarbon dioxideGrowth/MorphologySingle speciesOxygen standard deviationFugacity of carbon dioxide water at sea surface temperature wet airCoast and continental shelf
researchProduct

Templated Crystallisation of Calcium and Strontium Carbonates on Centred Rectangular Self-Assembled Monolayer Substrates

1998

SrCO3crystals display patterns of templating when grown on tailored self-assembled monolayers (right). As SrCO3 is isostructural with aragonite, comparison of the crystallisation of SrCO3 in the aragonite/strontianite modification with the crystallisation of CaCO3 in all three modifications might yield some insights into which factors are important for crystal growth.

StrontiumChemistryAragoniteOrganic Chemistrychemistry.chemical_elementCrystal growthSelf-assembled monolayerGeneral Chemistryengineering.materialCatalysisStrontianiteCrystallographyMonolayerengineeringIsostructuralBiomineralizationChemistry - A European Journal
researchProduct

2016

AbstractDetermining the manganese concentration in shells of freshwater bivalves provides a unique way to obtain information about climate and environmental changes during time-intervals that pre-date instrumental data records. This approach, however, relies on a thorough understanding of how manganese is incorporated into the shell material –a point that remained controversial so far. Here we clarify this issue, using state-of-the-art X-ray absorption and X-ray emission spectroscopy in combination with band structure calculations. We verify that in the shells of all studied species manganese is incorporated as high-spin Mn2+, i.e. manganese always has the same valence as calcium. More impo…

X-ray absorption spectroscopyMultidisciplinaryValence (chemistry)010504 meteorology & atmospheric sciencesAragoniteMineralogychemistry.chemical_elementManganeseBiologyengineering.material010502 geochemistry & geophysics01 natural sciencesAnimal Shellschemistry.chemical_compoundCalcium carbonatechemistryMollusc shellengineeringCarbonate14. Life underwater0105 earth and related environmental sciencesScientific Reports
researchProduct