Enrique Eduardo Boschi

This year a pioneer of marine sciences in our country has passed away. With a prolific and extensive professional life, Enrique dedicated himself both to research and teaching, as well as to institutional strengthening and consolidation work that he was able to develop both in Argentina and internationally, mainly in Latin America. This brief review of his career and contributions to research, teaching and institutional consolidation precedes the next appearance of a publicaion dealing with these aspects in detail, together with the list of his publications and works as editor.Este año nos ha dejado un pionero de las ciencias marinas de nuestro país. Con una vida profesionalprolífica y amplia, Enrique se dedicó tanto a la investigación y la docencia, como a labores de construccióny consolidación institucional que supo desarrollar tanto en Argentina como en el ámbito internacional,principalmente Latinoamericano. Este breve reordatorio sobre su trayectoria y aportes en investigación, docencia y consolidación institucional precede a la próxima aparición de un trabajo en el que trataremos en detalle estos aspectos en conjunto con el listado de sus publicaciones y de las obras de las que fue editor

Occurrence of marine biotoxins and shellfish poisoning events and their causative organisms in argentine marine waters

In the Argentine Sea, marine phycotoxins of microalgal origin associatedwith five shellfish poisoning syndromes have been reported. The most problematic interms of toxicity and geographic distribution is paralytic shellfish poisoning (PSP), followedby diarrhetic shellfish poisoning (DSP). In contrast, amnesic shellfish poisoning(ASP), spiroimine shellfish poisoning (SSP), and azaspiracid shellfish poisoning (AZP)have not been reported to cause human illness or closures of shellfish harvest sites inArgentina to date but pose a potential risk, as associated toxins and producing organismsare present in Southwest Atlantic waters and were detected at subregulatory levelsin mollusks. Alexandrium catenella and Gymnodinium catenatum have been identifiedas producers of the PSP toxins C1/2, gonyautoxins (GTX1-4), saxitoxin (STX),and neosaxitoxin (NEO) in the Argentine Sea. Nine potentially toxigenic species ofthe diatom genus Pseudo-nitzschia have been reported for Argentinean coastal waters:P. australis, P. brasiliana, P. delicatissima, P. fraudulenta, P. multiseries, P. pseudodelicatissima,P. pungens, P. seriata, and P. turgidula, all of which are known to produce theneurotoxin domoic acid that causes ASP. Two genera have been identified as producersof DSP toxins in Argentina: the benthic dinoflagellate Prorocentrum lima and severalspecies of the pelagic dinoflagellate genus Dinophysis: D. acuminata, D. caudata,D. fortii, D. norvegica, and D. tripos. The occurrence of these species in Argentine watersis associated with okadaic acid (OA), dinophysistoxin-1 (DTX-1), pectenotoxin-2(PTX-2), and pectenotoxin-2 seco acid (PTX-2sa). Historically, yessotoxins (YTXs)were also included in DSP syndrome and all three known YTX-producers have beenconfirmed in Argentinean waters: Gonyaulax spinifera, Lingulodinium polyedra, andProtoceratium reticulatum, but of these only P. reticulatum could be associated with YTXproduction to date. Several species of the family Amphidomataceae, which cause AZP,have been reported for Argentina: Amphidoma languida, Azadinium dexteroporum,Az. luciferelloides, Az. poporum, and Az. spinosum. In Argentinean coastal waters, outof these species only Az. poporum has been identified as toxigenic to date, as it producesazaspiracid-2 (AZA-2) and its phosphorylated form. Currently in Argentina, seafood ismonitored for the risk of ASP, AZP, DSP, and PSP.Fil: Krock, Bernd. Alfred-Wegener-Institut. Helmholtz-Zentrum für Polar und Meeresforschung; AlemaniaFil: Ferrario, Martha Elba. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Ficología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Akselman Cardella, Rut. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Montoya, Nora Gladys. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentin

Marine diatoms of Argentina: textile art-netting with science and art

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Daniel Raúl Hernández: Matemático

Daniel Hernández has passed away and after his disappearance our INIDEP community will no longer be the same...Daniel Hernández ha fallecido y luego de su desaparición nuestra comunidad del INIDEP ya no será la misma..

Mid- to Late Holocene organic-walled dinoflagellate cysts from the northern Argentine shelf

A Mid- to Late Holocene dinocyst record from the northern inner shelf of Argentina is described. It is analyzed with respect to the distribution of modern dinocysts, other Holocene records from the Buenos Aires province and the biogeographic distribution of planktonic dinocysts and their motile equivalents. Between ca. 5360 and 3300 14C yr BP the low diversity and abundance of the cyst assemblages can be related to a restricted littoral-subtidal environments. After ca. 3300 14C yr BP a major change is characterized by an increase in dinocyst abundance, indicating a normal inner neritic environment. The dominance of Operculodindium centrocarpum at some levels suggests some influence of continental shelf waters whereas the higher abundances of dinocysts from heterotrophic taxa e.g. Protoperidinium stellatum, Votadinium calvum, V. spinosum in other levels reflects a more inshore-coastal water influence with increased nutrient availability. Both assemblages are consistent with the present day transitional coastal-neritic conditions, suggesting that they were established after ca. 3300 14C yr. These inferences supplement those based on other proxies, reflecting sea-level decrease and the coastal geomorphological evolution post ca. 5360 14C yr BP.Fil: Vilanova, Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Laboratorio de Paleoecología y Palinología; ArgentinaFil: Guerstein, Gladys Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Akselman Cardella, Rut. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Subsede Instituto Nacional de Investigación y Desarrollo Pesquero; ArgentinaFil: Prieto, Aldo Raul. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Laboratorio de Paleoecología y Palinología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Environmental and biological factors controlling the spring phytoplankton bloom at the Patagonian shelf-break front - Degraded fucoxanthin pigments and the importance of microzooplankton grazing

The aim of this study was to investigate the biotic and abiotic factors controlling the spring phytoplankton blooms at the Patagonian shelf-break front (PSBF). Using a CHEMTAX analysis of HPLC pigment data and other methods, the biomass and spatial variability of plankton communities were studied in four sections (39-48°S) across the PSBF during October 2005. Environmental factors and the biomass and composition of plankton communities exhibited a marked spatial heterogeneity. The latitudinal and cross-shelf progression in the timing of the spring bloom initiation and the nutritive properties of the water masses (Subantarctic Shelf Waters and Malvinas Current Waters) seemed to be the key factors. Three plankton regions were distinguished: (a) Outer shelf (OS), (b) Shelf-break front (SBF) and (c) Malvinas Current (MC). At the highly stratified OS region, the post-bloom community showed low-biomasshigh-phytoplankton diversity formed mainly by small cells (haptophytes 30-62%, diatoms 17-49%, chlorophytes 0-34%, and prasinophytes 0-21% of total Chl a). High amounts of degraded fucoxanthin were found associated with the heterotrophic dinoflagellate, Protoperidinium capurroi. Grazing by this microheterotroph on the diatom population seemed to be the most important factor for the spring bloom decay at the OS. A remarkable quasi monospecific bloom (~90%) of a nanodiatom (Thalassiosira bioculata var. raripora) associated with high Chl a (up to 20 mg m-3) occurred along (~1000 km) the SBF and in the most northern extension of the MC. In the southern region, the bloom was developed under absent or incipient density stratification, increasing solar irradiance, high nitrate and phosphate availability, and low numbers of phytoplankton grazers. The average mixedlayer PAR irradiance (<2.0 mol quanta PAR m-2 d-1) and Si:N ratios (<0.2) were low, suggesting a diatom population limited by light and under progressive silicate limitation. The more stratified northern region of the SBF showed a later stage of the bloom development, but the large population of diatoms under Si limitation was not in senescence and losses from microzooplankton grazing were minor. The observed high proportion of Chl a below a shallow upper mixed layer (up to 85%) could directly reach the bed, favoring the development of epibenthic communities and the formation of seed diatom banks and organic iron-rich sediments. The upwelling along the SBF provides a large source of macronutrients and probably the dissolved iron needed to sustain the intense diatom bloom, but also diatom resting stages that could act as seeds for the next spring bloom. The macronutrient-rich MC region showed low chlorophyll (Chl a < 0.8 mg m-3) and a highly diverse phytoplankton community, mainly composed of small cells (diatoms 20-70%, haptophytes 20-40%, chlorophytes 2-25%, prasinophytes 2-18%, and cryptophytes 3-12% of total Chl a).Fil: Carreto Iraurgui, Jose Ignacio. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Montoya, Nora Gladys. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Carignan, Mario O.. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Akselman Cardella, Rut. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Acha, Eduardo Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Derisio, Carla María. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentin

Shionodiscus gaarderae sp. nov. (Thalassiosirales, Thalassiosiraceae), a bloom-producing diatom from the southwestern Atlantic Ocean, and emendation of Shionodiscus bioculatus var. bioculatus

The recently established diatom genus Shionodiscus is characterized as possessing a labiate process on the valve face and strutted processes with long internal and reduced, or no, external extensions. Many Thalassiosira species with these features were transferred to this new genus, as well as some with short internal, strutted process extensions. Examination of samples from the Argentine continental shelf and slope waters, and from the Beagle Channel, revealed the presence of a small centric diatom that formed an extensive bloom in slope waters during spring 2005 and 2006. Analysis by light and electron microscopy revealed high similarity to specimens previously referred as Thalassiosira bioculata var. raripora. This name was never effectively published; nevertheless, the name has been adopted and observations referring to it have been reported on several occasions. Here we trace the usage of the (nomenclaturally invalid) name Thalassiosira bioculata var. raripora in the literature, and formally describe the species as Shionodiscus gaarderae, based on our observations and comparison with previous reports. A morphological comparison of this and similar taxa is also provided. In addition, we offer an emended description of S. bioculatus var. bioculatus from Ostenfeld material sampled from the ‘Färöer Island Naströ Fjord Plankton (16.9.1902)’, held in the Hustedt collection. Finally, we propose the transfer of Thalassiosira rosulata to Shionodiscus.Fil: Ferrario, Martha Elba. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Ficología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Almandoz, Gaston Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Ficología; ArgentinaFil: Cefarelli, Adrián Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Instituto de Desarrollo Costero; ArgentinaFil: Beszteri, Bank. Helmholtz-Zentrum für Polar- und Meeresforschung. Alfred-Wegener-Institut; AlemaniaFil: Akselman Cardella, Rut. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Subsede Instituto Nacional de Investigación y Desarrollo Pesquero; ArgentinaFil: Fabro Cerreia Fus, Elena Ines. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Ficología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Cembella, Allan. Helmholtz-Zentrum für Polar- und Meeresforschung. Alfred-Wegener-Institut; Alemani