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Mostrando entradas de agosto, 2022

EL GRUPO QUIMA (IOCAG, ULPGC) PUBLICA EL ESTUDIO DE LA ACIDIFICACIÓN OCEÁNICA PRODUCIDA EN LA INTERFASE AGUA-LAVA DURANTE LA ERUPCIÓN EN LA ISLA DE LA PALMA

El grupo QUIMA (IOCAG, ULPGC) ha publicado un artículo científico en la revista de alto índice de impacto Frontiers in Marine Science donde se ha estudiado la evolución de la acidificación de las aguas y el contenido de carbonatos en el frente lávico formado en la isla de La Palma como consecuencia de la erupción volcánica del Tajogaite. Este trabajo se ha titulado “ Coastal carbonate system variability along an active lava–seawater interface ”. Las coladas de lava llegaron al mar el día 28 de Septiembre, 10 de Noviembre y 22 de Noviembre, afectando a las propiedades físico-químicas de la superficie y la zona costera. Durante 13 visitas a la zona a bordo de las embarcaciones de Salvamento Marítimo (Salvamar Alphard) y de la Guardia Civil, el grupo QUIMA midió parámetros de interés como la Temperatura, la Salinidad, el Sistema de Carbonatos (pH, alcalinidad, carbono inorgánico y contenido de CO2 disuelto) y el Oxígeno Disuelto en toda la zona costera de formación de los deltas. Lo

WHAT CHANGES OCCUR IN THE ORGANIC COMPOUNDS OF ALGAE WHEN WE SUBJECT THEM TO HIGH CONCENTRATIONS OF METALS?

English version To answer this question, the QUIMA group studied the  accumulation of free amino acids in the diatom cells of  Phaeodactylum tricornutum . We make here a summary of the results presented at the Week of Marine Sciences in Gran Canaria.   Behaviour of free amino acids in  Phaeodactylum tricornutum  cells under copper stress Microalgae can provide information on the potential impacts of copper. The diatom  Phaeodactylum tricornutum  is one of the most abundant photosynthetic organisms in marine ecosystems and is commonly used in toxicity tests. Although the effects of heavy metals in its growth have been studied, the biochemical response of these microorganisms cultivated under Cu stress is still not fully understood. The marine diatom  Phaeodactylum tricornutum  was cultivated under diverse copper concentrations to study the accumulation of free amino acids in the diatom cells. Under lethal copper doses the diatom growth was inhibited and caused  an important cellular dam

WHAT CHANGES OCCUR IN THE ORGANIC COMPOUNDS EXCRETED BY THE PHYTOPLANKTON DUE TO OCEAN ACIDIFICATION?

English version To answer this question, the QUIMA group studied the  extracellular release of  phenolics from  E. huxleyi  under future  marine ocean acidification  scenarios . We make here a summary of the results presented at the Week of Marine Sciences in Gran Canaria.   Influence of seawater acidification on the phenolic profile of  Emiliania huxleyi Samples of seawater with exudates from coccolithophore  Emiliania huxleyi  cultivated under different pH conditions (7.75, 7.9, 8.1 and 8.25) were studied  to improve the understanding of the extracellular release of organic ligands under future  marine acidification  scenarios. T he phenolic profile of seawater samples enriched with  E. huxleyi  exudates are summarized in Figure 1.  Gallic acid, protocatechuic acid, catechin, vanillic acid and syringic acid were identified, being the last two detected in all pHs studied. The highest concentrations of total exuded polyphenols were found in cultures at pH 7.75 (5.04 µg L -1 ) and 8.25

DOES OCEAN ACIDIFICATION AFFECT THE INTERACTION OF Fe WITH ORGANIC COMPOUNDS? - AFECTA LA ACIDIFICACIÓN OCEÁNICA A LA INTERACCIÓN DEL Fe CON LOS COMPUESTOS ORGÁNICOS?

English version T o answer this question, the QUIMA group studied the interaction of Galic acid and iron. We make here a summary of the results presented at the Week of Marine Sciences in Gran Canaria.   The role of galic acid and ocean acidification in the redox chemistry of iron in seawater Iron is a trace metal that influences ocean productivity. Numerous research works have documented that the bioavailability of iron in the ocean is conditioned by the presence of organic matter and by the pH of the medium, so there is no doubt that ocean acidification will play an important role in the biogeochemical cycle of Fe. It is important to point out that, in general, the research works that study the role of organic matter in the chemistry of iron in SW do not do so on a specific ligand but on a mixture of natural ligands with a high capacity to complex metals. Information on the individual organic compounds that are part of this ligand mixture and their role in iron chemistry is therefore