Consulta: creatorFacets:"Lacour, Thomas"
Registros recuperados: 4
Data/hora: 02/06/2024 16:45:54

The Role of Sustained Photoprotective Non-photochemical Quenching in Low Temperature and High Light Acclimation in the Bloom-Forming Arctic Diatom Thalassiosira gravida
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Lacour, Thomas; Lariviere, Jade; Ferland, Joannie; Bruyant, Flavienne; Lavaud, Johann; Babin, Marcel.
Thalassiosira gravida is a major Arctic diatom responsible for the under-ice spring bloom. We investigated T. gravida physiological plasticity growing it at two temperatures (0 and 5°C) and under different light intensities typically found in its natural environment. T. gravida showed remarkable thermal- and photo-acclimatory plasticity including: low light saturation parameter for growth (KE) and photosynthesis (EK), low μmax but relatively high Chl a/C, low C/N, and decreasing light-saturated carbon fixation rate (PmC) with increasing growth irradiance. T. gravida also showed remarkable photoprotective features, namely a strong sustained non-photochemical quenching (NPQs, hour kinetics relaxation) supported by a high amount of xanthophyll cycle pigments....
Tipo: Text
Palavras-chave: Arctic diatom; Photosynthesis; Sustained NPQ; Irradiance; Temperature.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00462/57387/59468.pdf

Diversity in Xanthophyll Cycle Pigments Content and Related Nonphotochemical Quenching (NPQ) Among Microalgae: Implications for Growth Strategy and Ecology
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Lacour, Thomas; Babin, Marcel; Lavaud, Johann.
Xanthophyll cycle‐related non‐photochemical quenching, which is present in most photoautotrophs, allows dissipating excess light energy. Xanthophyll cycle‐related NPQ depends principally on xanthophyll cycle pigments composition and their effective involvement in non‐photochemical quenching. Xanthophyll cycle‐related NPQ is tightly controlled by environmental conditions in a species/strain specific manner. These features are especially relevant in microalgae living in a complex and highly variable environment. The goal of this study was to perform a comparative assessment of non‐photochemical quenching ecophysiologies across microalgal taxa in order to underline specific involvement of non‐photochemical quenching in growth adaptations and strategies. We...
Tipo: Text
Palavras-chave: Diatoxanthin; Diversity; Microalgae; Nonphotochemical quenching; Photoacclimation; Pigments; Xanthophyll cycle; Zeaxanthin.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00590/70243/68267.pdf

Decoupling light harvesting, electron transport and carbon fixation during prolonged darkness supports rapid recovery upon re-illumination in the Arctic diatom Chaetoceros neogracilis
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Lacour, Thomas; Morin, Philippe-israël; Sciandra, Théo; Donaher, Natalie; Campbell, Douglas A.; Ferland, Joannie; Babin, Marcel.
During winter in the Arctic marine ecosystem, diatoms have to survive long periods of darkness caused by low sun elevations and the presence of sea ice covered by snow. To better understand how diatoms survive in the dark, we subjected cultures of the Arctic diatom Chaetoceros neogracilis to a prolonged period of darkness (1 month) and to light resupply. Chaetoceros neogracilis was not able to grow in the dark but cell biovolume remained constant after 1 month in darkness. Rapid resumption of photosynthesis and growth recovery was also found when the cells were transferred back to light at four different light levels ranging from 5 to 154 µmol photon m−2 s−1. This demonstrates the remarkable ability of this species to re-initiate growth over a wide range...
Tipo: Text
Palavras-chave: Arctic microalgae; Polar night; Diatom; Darkness; Photosynthesis; Growth rate; Temperature.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00499/61066/64597.pdf

Green Edge ice camp campaigns: understanding the processes controlling the under-ice Arctic phytoplankton spring bloom
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Massicotte, Philippe; Amiraux, Rémi; Amyot, Marie-pier; Archambault, Philippe; Ardyna, Mathieu; Arnaud, Laurent; Artigue, Lise; Aubry, Cyril; Ayotte, Pierre; Bécu, Guislain; Bélanger, Simon; Benner, Ronald; Bittig, Henry C; Bricaud, Annick; Brossier, Eric; Bruyant, Flavienne; Chauvaud, Laurent; Christiansen-stowe, Debra; Claustre, Hervé; Cornet-barthaux, Véronique; Coupel, Pierre; Cox, Christine; Delaforge, Aurélie; Dezutter, Thibault; Dimier, Céline; Dominé, Florent; Dufour, Francis; Dufresne, Christiane; Dumont, Dany; Ehn, Jens; Else, Brent; Ferland, Joannie; Forget, Marie-hélène; Fortier, Louis; Gali, Marti; Galindo, Virginie; Gallinari, Morgane; Garcia, Nicole; Gerikas-ribeiro, Catherine; Gourdal, Margaux; Gourvil, Priscilla; Goyens, Clemence; Grondin, Pierre-luc; Guillot, Pascal; Guilmette, Caroline; Houssais, Marie-noëlle; Joux, Fabien; Lacour, Léo; Lacour, Thomas; Lafond, Augustin; Lagunas, José; Lalande, Catherine; Laliberté, Julien; Lambert-girard, Simon; Larivière, Jade; Lavaud, Johann; Lebaron, Anita; Leblanc, Karine; Le Gall, Florence; Legras, Justine; Lemire, Mélanie; Levasseur, Maurice; Leymarie, Edouard; Leynaert, Aude; Lopes Dos Santos, Adriana; Lourenço, Antonio; Mah, David; Marec, Claudie; Marie, Dominique; Martin, Nicolas; Marty, Constance; Marty, Sabine; Massé, Guillaume; Matsuoka, Atsushi; Matthes, Lisa; Moriceau, Brivaela; Muller, Pierre-emmanuel; Mundy, Christopher-john; Neukermans, Griet; Oziel, Laurent; Panagiotopoulos, Christos; Pangazi, Jean-jacques; Picard, Ghislain; Picheral, Marc; Pinczon Du Sel, France; Pogorzelec, Nicole; Probert, Ian; Queguiner, Bernard; Raimbault, Patrick; Ras, Joséphine; Rehm, Eric; Reimer, Erin; Rontani, Jean-françois; Rysgaard, Soren; Saint-béat, Blanche; Sampei, Makoto; Sansoulet, Julie; Schmidt, Sabine; Sempere, Richard; Sevigny, Caroline; Shen, Yuan; Tragin, Margot; Tremblay, Jean-eric; Vaulot, Daniel; Verin, Gauthier; Vivier, Frédéric; Vladoiu, Anda; Whitehead, Jeremy; Babin, Marcel.
The Green Edge initiative was developed to investigate the processes controlling the primary productivity and the fate of organic matter produced during the Arctic phytoplankton spring bloom (PSB) and to determine its role in the ecosystem. Two field campaigns were conducted in 2015 and 2016 at an ice camp located on landfast sea ice southeast of Qikiqtarjuaq Island in Baffin Bay (67.4797N, 63.7895W). During both expeditions, a large suite of physical, chemical and biological variables was measured beneath a consolidated sea ice cover from the surface to the bottom at 360 m depth to better understand the factors driving the PSB. Key variables such as temperature, salinity, radiance, irradiance, nutrient concentrations, chlorophyll-a concentration,...
Tipo: Text
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00598/71000/69266.pdf