Search results for "Biomas"

showing 10 items of 980 documents

Early sowing can boost grain production by reducing weed infestation in organic no‐till wheat

2022

Conservative tillage techniques have several agro-ecological benefits for organic farming. The application of these techniques, however, can create quite a few challenges due to the increased weed competition. Here, we report the results of an organic field experiment in which the responses of wheat and weeds to no tillage (NT) were evaluated compared with conventional tillage (CT). We also tested the hypothesis that, under NT, moving up the sowing date, compared with using the ordinary sowing date for the study area, can result in increased competitiveness of the crop against weeds. Two wheat genotypes, a modern variety and an ancient landrace, were tested.Substantial reductions in grain y…

Nutrition and DieteticsMediterranean environmentAgricultureweed flora compositionSettore AGR/02 - Agronomia E Coltivazioni ErbaceeSoilTriticum durumno tillageorganic farmingBiomassEdible GrainAgronomy and Crop ScienceTriticumFood ScienceBiotechnologyJournal of the Science of Food and Agriculture
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Modeling the decay of nitrite oxidizing bacteria under different reduction potential conditions

2018

[EN] Autotrophic growth and decay rates of ammonium and nitrite oxidizing bacteria (AOB and NOB, respectively) have a significant impact on the design and on the process performance of wastewater treatment systems where nitrification occurs. Literature data on the separate decay rates of AOB and NOB is scarce and inconsistent. In this study, batch experiments based on respirometric techniques were conducted to determine the NOB decay rates under different oxidation-reduction potential conditions, in order to widen the understanding of nitrite dynamics. The decay rate measured under anoxic conditions was 85% lower than under aerobic conditions, whereas under anaerobic conditions the decay ra…

OUR RespirometryINGENIERIA HIDRAULICA0208 environmental biotechnologyBiomassBioengineering02 engineering and technology010501 environmental sciences01 natural sciencesApplied Microbiology and BiotechnologyBiochemistryAmmonia oxidizing bacteria (AOB)chemistry.chemical_compoundAmmoniumNitriteEffluentTECNOLOGIA DEL MEDIO AMBIENTE0105 earth and related environmental sciencesNitrite oxidizing bacteria (NOB)ChemistryAnoxic waters020801 environmental engineeringDecay rateActivated sludgeEnvironmental chemistryNitrificationSewage treatment
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Seawater carbonate chemistry and biogenic habitat shifts under long-term ocean acidification

2023

Experiments have shown that increasing dissolved CO2 concentrations (i.e. Ocean Acidification, OA) in marine ecosystems may act as nutrient for primary producers (e.g. fleshy algae) or a stressor for calcifying species (e.g., coralline algae, corals, molluscs). For the first time, rapid habitat dominance shifts and altered competitive replacement from a reef-forming to a non-reef-forming biogenic habitat were documented over one-year exposure to low pH/high CO2 through a transplant experiment off Vulcano Island CO2 seeps (NE Sicily, Italy). Ocean acidification decreased vermetid reefs complexity via a reduction in the reef-building species density, boosted canopy macroalgae and led to chang…

Ocean Acidification International Coordination Centre (OA-ICC)IdentificationSalinityTemperateCommunity composition and diversityinorganicAlkalinityDensityType of studyExperimentTemperature waterCarbon inorganic dissolvedAbundanceCalculated using seacarb after Nisumaa et al 2010Aragonite saturation stateAlkalinity totalSalinity standard errortotalCO2 ventpHTemperaturePartial pressure of carbon dioxide (water) at sea surface temperature (wet air) standard errordissolvedCarbonate ionPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)Field experimentstandard errorEarth System ResearchPotentiometric titrationCalcite saturation stateCoveragePotentiometricwaterSiteRocky-shore communityAlkalinity total standard errorBenthosReplicateMediterranean SeaOcean Acidification International Coordination Centre OA ICCBicarbonate ionTemperature water standard errorCalculated using seacarb after Nisumaa et al. (2010)pH standard errorCalculated using CO2SYSCarbonate system computation flagComplexityFugacity of carbon dioxide (water) at sea surface temperature (wet air)CarbonBiomass/Abundance/Elemental compositionAragonite saturation state standard errorPartial pressure of carbon dioxide water at sea surface temperature wet airCarbon dioxideEntire communityRocky shore communityFugacity of carbon dioxide water at sea surface temperature wet airBiomass Abundance Elemental compositionCoast and continental shelfSpecies richness
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Seaweed fails to prevent ocean acidification impact on foraminifera along a shallow-water CO2 gradient

2015

Ocean acidification causes biodiversity loss, alters ecosystems, and may impact food security, as shells of small organisms dissolve easily in corrosive waters. There is a suggestion that photosynthetic organisms could mitigate ocean acidification on a local scale, through seagrass protection or seaweed cultivation, as net ecosystem organic production raises the saturation state of calcium carbonate making seawater less corrosive. Here, we used a natural gradient in calcium carbonate saturation, caused by shallow-water CO2 seeps in the Mediterranean Sea, to assess whether seaweed that is resistant to acidification (Padina pavonica) could prevent adverse effects of acidification on epiphytic…

Ocean Acidification International Coordination Centre (OA-ICC)TemperateIdentificationSalinityCommunity composition and diversityTriloculinella dilatatainorganicAlkalinityElphidium spMiliolinella sp.Miliolinella subrotundaQuinqueloculina sp.Daitrona spTemperature waterCarbon inorganic dissolvedCalculated using seacarb after Nisumaa et al 2010Adelosina longirostraPercentageAragonite saturation stateMiliolinella spRosalina globularisAlkalinity totaltotalElphidium sp.Elphidium crispumCO2 ventElphidium advenumpHTemperaturedissolvedPseudotriloculina spCarbonate ionPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)Rosalina spQuinqueloculina annectensEarth System ResearchHaynesina depressulaField observationElphidium margaritaceumPotentiometric titrationCalcite saturation statePotentiometricwaterMassilina gualtierianaRocky-shore communitySpiroloculina ornataQuinqueloculina auberianaBenthosDaitrona sp.Pileolina patelliformisOcean Acidification International Coordination Centre OA ICCMediterranean SeaBicarbonate ionCalculated using seacarb after Nisumaa et al. (2010)SpeciesVertebralina striataAffinetrina gualtierianaElphidium macellumCalculated using CO2SYSIndividualsCarbonate system computation flagFugacity of carbon dioxide (water) at sea surface temperature (wet air)Rosalina sp.CarbonBiomass/Abundance/Elemental compositionBolivina pseudoplicataPartial pressure of carbon dioxide water at sea surface temperature wet airCarbon dioxideQuinqueloculina stelligeraQuinqueloculina spPeneroplis pertususRocky shore communityEntire communityPeneroplis planatusFugacity of carbon dioxide water at sea surface temperature wet airCornuspira involvensBiomass Abundance Elemental compositionCoast and continental shelfLobatula lobatulaQuinqueloculina boscianaPseudotriloculina sp.
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Seawater carbonate chemistry and carbon sources of mussel shell carbonate

2018

Ocean acidification and warming is widely reported to affect the ability of marine bivalves to calcify, but little is known about the underlying mechanisms. In particular, the response of their calcifying fluid carbonate chemistry to changing seawater carbonate chemistry remains poorly understood. The present study deciphers sources of the dissolved inorganic carbon (DIC) in the calcifying fluid of the blue mussel (Mytilus edulis) reared at two pH (8.1 and 7.7) and temperature (16 and 22 °C) levels for five weeks. Stable carbon isotopic ratios of seawater DIC, mussel soft tissues and shells were measured to determine the relative contribution of seawater DIC and metabolically generated carb…

Ocean Acidification International Coordination Centre (OA-ICC)TemperateRegistration number of speciesSalinityMytilus edulisinorganicAlkalinityExperimentTemperature waterCarbon inorganic dissolvedhemic and lymphatic diseasesCalculated using seacarb after Nisumaa et al 2010PercentageAragonite saturation stateNorth Pacificδ13C dissolved inorganic carbon standard deviationAlkalinity totalSalinity standard errortotalpHTemperaturePartial pressure of carbon dioxide (water) at sea surface temperature (wet air) standard errordissolvedLaboratory experimentCarbonate ionPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)standard errorContainers and aquaria 20 1000 L or 1 m 2δ13C dissolved inorganic carbonEarth System Researchδ13CContainers and aquaria (20-1000 L or &lt; 1 m**2)standard deviationUniform resource locator link to referencecirculatory and respiratory physiologyCalcite saturation statewaterContainers and aquaria (20-1000 L or < 1 m**2)BenthosAlkalinity total standard errorUniform resource locator/link to referenceOcean Acidification International Coordination Centre OA ICCAnimaliaTypeBicarbonate ionTemperature water standard errorCalculated using seacarb after Nisumaa et al. (2010)SpeciespH standard errorCalcite saturation state standard errorCarbonate system computation flagdissolved inorganic carbonFugacity of carbon dioxide (water) at sea surface temperature (wet air)CarbonBiomass/Abundance/Elemental compositionPartial pressure of carbon dioxide water at sea surface temperature wet airCarbon dioxideMolluscaSingle speciesFugacity of carbon dioxide water at sea surface temperature wet airBenthic animalsδ13C standard deviationBiomass Abundance Elemental compositionCoast and continental shelf
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Individual and population-level responses to ocean acidification

2016

Ocean acidification is predicted to have detrimental effects on many marine organisms and ecological processes. Despite growing evidence for direct impacts on specific species, few studies have simultaneously considered the effects of ocean acidification on individuals (e.g. consequences for energy budgets and resource partitioning) and population level demographic processes. Here we show that ocean acidification increases energetic demands on gastropods resulting in altered energy allocation, i.e. reduced shell size but increased body mass. When scaled up to the population level, long-term exposure to ocean acidification altered population demography, with evidence of a reduction in the pr…

Ocean Acidification International Coordination Centre (OA-ICC)TemperateRegistration number of speciesSalinityinorganicBottles or small containers/Aquaria (<20 L)AlkalinityExperimentTemperature waterCarbon inorganic dissolvedCalculated using seacarb after Nisumaa et al 2010Aragonite saturation stateRespiration rate oxygenBottles or small containers Aquaria 20 LAlkalinity totalSalinity standard errortotalCO2 ventpHRespirationTemperaturedissolvedCarbonate ionPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)Field experimentstandard errorCarbon inorganic dissolved standard errorRespiration rateEarth System ResearchSexUniform resource locator link to referencePotentiometric titrationCalcite saturation stateDry masswaterSiteHexaplex trunculusBenthosAlkalinity total standard errorUniform resource locator/link to referenceOcean Acidification International Coordination Centre OA ICCMediterranean SeaAnimaliaTypeBicarbonate ionTemperature water standard errorCalculated using seacarb after Nisumaa et al. (2010)SpeciesWet massBottles or small containers/Aquaria (&lt;20 L)Calculated using CO2SYSCarbonate system computation flagFugacity of carbon dioxide (water) at sea surface temperature (wet air)CarbonBiomass/Abundance/Elemental compositionTreatmentPartial pressure of carbon dioxide water at sea surface temperature wet airCarbon dioxideMolluscaSingle speciesFugacity of carbon dioxide water at sea surface temperature wet airBenthic animalsBiomass Abundance Elemental compositionCoast and continental shelfoxygen
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Macroalgal responses to ocean acidification depend on nutrient and light levels

2015

Ocean acidification may benefit algae that are able to capitalize on increased carbon availability for photosynthesis, but it is expected to have adverse effects on calcified algae through dissolution. Shifts in dominance between primary producers will have knock-on effects on marine ecosystems and will likely vary regionally, depending on factors such as irradiance (light vs. shade) and nutrient levels (oligotrophic vs. eutrophic). Thus experiments are needed to evaluate interactive effects of combined stressors in the field. In this study, we investigated the physiological responses of macroalgae near a CO2 seep in oligotrophic waters off Vulcano (Italy). The algae were incubated in situ …

Ocean Acidification International Coordination Centre (OA-ICC)TemperateSalinityChlorophyll aFucoxanthininorganicAlkalinityPhotosynthetic efficiency standard errorChlorophyll cNitrogen content per dry mass standard errorLight saturation point standard errorPhenolics allTemperature waterCarbon inorganic dissolvedMacroalgaeCalculated using seacarb after Nisumaa et al 2010Carbon Nitrogen ratioAragonite saturation stateAlkalinity totalallCarbon per dry massSalinity standard errortotalCarbon content per dry mass standard errorPhenolics all standard errorCO2 ventChromistapHMaximum photochemical quantum yield of photosystem II standard errorTemperaturePartial pressure of carbon dioxide (water) at sea surface temperature (wet air) standard errordissolvedAntioxidant activity standard errorCarbonate ionMaximum photochemical quantum yield of photosystem IIPartial pressure of carbon dioxide (water) at sea surface temperature (wet air)Field experimentstandard errorNitrogen content per dry massElectron transport rate standard errorFucoxanthin standard errorEarth System ResearchViolaxanthinPhenolicsChlorophyll a standard errorCarbon dioxide standard errorPotentiometric titrationCalcite saturation stateCarbon/Nitrogen ratio standard errorNitrogenOchrophytaPotentiometricper dry masswaterChlorophyll c standard errorBenthosAlkalinity total standard errorAntioxidant activityElectron transport rateLight saturation pointOcean Acidification International Coordination Centre OA ICCMacro-nutrientsMediterranean SeaNitrogen per dry massBicarbonate ionTemperature water standard errorCalculated using seacarb after Nisumaa et al. (2010)Primary production PhotosynthesisSpeciespH standard errorCalcite saturation state standard errorCystoseira compressaCalculated using CO2SYSNon photochemical quenchingCarbon content per dry massCarbonate system computation flagViolaxanthin standard errorPrimary production/PhotosynthesisFugacity of carbon dioxide (water) at sea surface temperature (wet air)CarbonCarbon/Nitrogen ratioBiomass/Abundance/Elemental compositionTreatmentPartial pressure of carbon dioxide water at sea surface temperature wet airAragonite saturation state standard errorCarbon dioxideMacro nutrientsCarbonate ion standard errorSingle speciesFugacity of carbon dioxide water at sea surface temperature wet airPadina pavonicaBiomass Abundance Elemental compositionCoast and continental shelfPhotosynthetic efficiencyBicarbonate ion standard errorNon photochemical quenching standard error
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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
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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
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On the ecology of littoral Oligochaeta of an oligotrophic Finnish lake

1982

In material sampled from 0.5–6 m on two sampling dates and three subareas the dominant Oligochaeta were Limnodrilus hoffmeisteri Claparede and Peloscolex ferox (Eisen), both composing more than 30% of the abundances of oligochaetes present. The numbers of Oligochaeta were mostly higher in August than in May. Regional differences could be found although the lake seems to be very homogenous. Temporal and vertical variations were detectable in separate subareas. The oligochaete biomass was maximal at 2 m depth. In soft bottom sediments the oligochaetes composed 15.9% of macrobenthos biomass and 12.2% of numbers, but on the stony bottom only 1.9% of numbers. The ratio of Oligochaeta/Chironomida…

Oligochaeta (plant)Biomass (ecology)Limnodrilus hoffmeisteribiologyEcologyMacrobenthosNicheLittoral zonebiology.organism_classificationChironomidaeEcology Evolution Behavior and SystematicsRegional differencesEcography
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