Alicia Viviana Sastre - Academia.edu (original) (raw)
Uploads
Papers by Alicia Viviana Sastre
Zenodo (CERN European Organization for Nuclear Research), Sep 6, 2022
SIL Proceedings, 1922-2010, 1994
The purpose of this study is to review as well as to compare environmental and phytoplankton data... more The purpose of this study is to review as well as to compare environmental and phytoplankton data collected from coastal Patagonian ecosystems (Argentina) located at different latitudes and exposed not only to freshwater discharges (Chubut river in Chubut province, Deseado river in Santa Cruz province, Pipo and Olivia rivers in Tierra del Fuego province) but also to urban, industrial, and port activities related to the main cities on the Patagonian coast. The data analyzed were collected during the spring, summer, and fall of 1993, 1994, and 2001. The presence of Bacillariophyta, the dominant phylum in most environments, is the main characteristic of the composition and structure of phytoplankton community in the study area. A total of 127 taxa were identified, 9 of which are known to be potentially toxic species. Taxa richness was found to be highest in Nueva and Engano Bays, the order of abundance being 106 cells L−1 in the majority of the environments of our study area. Blooms of...
Plankton Ecology of the Southwestern Atlantic, 2018
A Harmful Algal Blooms Regional Monitoring Program has been carried out in Chubut coastal waters ... more A Harmful Algal Blooms Regional Monitoring Program has been carried out in Chubut coastal waters (Patagonia, Argentina) since the year 2000. This program surveys an extended shoreline, with bays and gulfs with shellfish natural banks and farms. Paralytic shellfish poison (PSP)-toxin-producing species, A. tamarense, have been observed during the study period; in addition, species producing diarrheic shellfish poison (DSP)-toxins, such as Dinophysis acuminata and D. tripos and Prorocentrum lima, and amnesic shellfish poison (ASP)-toxins, as several species of genus Pseudo-nitzschia, have been identified. Moreover, the production of the three types of toxins has been proven. Other harmful but nontoxic species have been registered in the area. The aim of this review is to show the temporal and spatial distribution of harmful microalgae species, the environmental factors associated with their occurrence, and their relation to toxic outbreaks during more than 15 years of observations, with special attention focused on the episodes of human intoxications. In addition, we discussed the accumulation and transfer of some phycotoxins through pelagic food webs, from the first trophic levels to large marine mammals, such as whales.
Aquatic Ecosystem Health & Management, 2017
Large nuisance blooms of Didymosphenia geminata have become increasingly widespread in Patagonia.... more Large nuisance blooms of Didymosphenia geminata have become increasingly widespread in Patagonia. Although the first published account for South America was in 1964, reports of large growths in Chile and Argentina commenced around 2010. Since then, these blooms have been observed all along the Andes region to the south of parallel 42°S. General surveys are needed to help provide an explanation. Possibilities include one or more new genetic variants or responses of local populations to global environmental changes. Electron microscopy of material from the Argentinean Patagonia revealed marked differences between regions, though it is unclear how much local factors and/or variations in life cycle contribute. Thus, we are approaching the problem from a molecular perspective, which we hope will help to overcome this limitation. Initial studies showed that D. geminata seems to be highly recalcitrant to DNA extraction, thus hindering the survey of molecular markers. We have now developed ...
Boletín de la Sociedad Argentina de Botánica, 2016
Morfología valvar de Didymosphenia geminata (Bacillariophyceae) en la provincia de Chubut, Argent... more Morfología valvar de Didymosphenia geminata (Bacillariophyceae) en la provincia de Chubut, Argentina. Recientemente se verificó que Didymosphenia forma proliferaciones masivas en Patagonia.En Argentina se ha esparcido a cinco provincias en un corto tiempo. En este trabajo, analizamos datos morfológicos y morfométricos de especímenes recolectados en la provincia del Chubut, Argentina y los comparamos con otras especies de este género de diferentes regiones del mundo. El material de estudio fue recolectado en dos cuencas durante 2010-2012. Las muestras, analizadas con MO y MEB, mostraron variación inter e intra-poblacional en las características morfométricas y en algunas estructuras valvares, como espinas. La morfología del material estudiado corresponde a la de D. geminata ssp geminata Metzeltin & Lange-Bertalot. Nuestros materiales también se asemejan a las especies: D. clavaherculis,D. clavamagna, D. coronata y D. laticollis. Los materiales de Chubut pueden ser fácilmente confund...
Boletín de la Sociedad Argentina de Botánica, 2019
Introducción y objetivos: Didymosphenia geminata, diatomea declarada “Especie Exótica Invasora” e... more Introducción y objetivos: Didymosphenia geminata, diatomea declarada “Especie Exótica Invasora” en Argentina por la Secr. Ambiente y Desarrollo Sustentable de la Nación. Esta especie coloniza rocas y puede formar grandes matas mucilaginosas que cubren el lecho de los ríos, ocasionando un considerable impacto estético y provocando serias alteraciones en los ecosistemas. En los últimos 9 años la especie ha colonizado ríos andino-patagónicos y ha aumentado considerablemente su distribución en la región. El objetivo de este trabajo es analizar la dinámica de esta especie en la Patagonia argentina mediante el uso de SIG.M&M: los datos provienen de resultados obtenidos por el grupo de trabajo en las provincias del Neuquén y del Chubut e información abierta y libre disponible en la web. Se generó una base de datos a escala regional abarcando desde Neuquén a Tierra del Fuego.Resultados: fueron incorporados a un SIG, lo que permitió generar mapas de distribución a nivel provincial y nacional...
Continental Shelf Research, 2018
Journal of Shellfish Research, 2015
Marine Mammal Science, 2015
Península Valdés (PV) in Argentina is an important calving ground for southern right whales (SRWs... more Península Valdés (PV) in Argentina is an important calving ground for southern right whales (SRWs, Eubalaena australis). Since 2005, right whale mortality has increased at PV, with most of the deaths (~90%) being calves <3 mo old. We investigated the potential involvement of harmful algal blooms (HABs) in these deaths by examining data that include: timing of the SRW deaths, biotoxins in samples from dead SRWs, abundances of the diatom, Pseudo‐nitzschia spp., and the dinoflagellate, Alexandrium tamarense, shellfish harvesting closure dates, seasonal availability of whale prey at PV and satellite chlorophyll data. Evidence of the whales' exposure to HAB toxins includes trace levels of paralytic shellfish toxins (PSTs) and domoic acid (DA) in tissues of some dead whales, and fragments of Pseudo‐nitzschia spp. frustules in whale feces. Additionally, whales are present at PV during both closures of the shellfish industry (due to high levels of PSTs) and periods with high levels o...
BioInvasions Records, 2013
Journal of Marine Systems, 2012
Zenodo (CERN European Organization for Nuclear Research), Sep 6, 2022
SIL Proceedings, 1922-2010, 1994
The purpose of this study is to review as well as to compare environmental and phytoplankton data... more The purpose of this study is to review as well as to compare environmental and phytoplankton data collected from coastal Patagonian ecosystems (Argentina) located at different latitudes and exposed not only to freshwater discharges (Chubut river in Chubut province, Deseado river in Santa Cruz province, Pipo and Olivia rivers in Tierra del Fuego province) but also to urban, industrial, and port activities related to the main cities on the Patagonian coast. The data analyzed were collected during the spring, summer, and fall of 1993, 1994, and 2001. The presence of Bacillariophyta, the dominant phylum in most environments, is the main characteristic of the composition and structure of phytoplankton community in the study area. A total of 127 taxa were identified, 9 of which are known to be potentially toxic species. Taxa richness was found to be highest in Nueva and Engano Bays, the order of abundance being 106 cells L−1 in the majority of the environments of our study area. Blooms of...
Plankton Ecology of the Southwestern Atlantic, 2018
A Harmful Algal Blooms Regional Monitoring Program has been carried out in Chubut coastal waters ... more A Harmful Algal Blooms Regional Monitoring Program has been carried out in Chubut coastal waters (Patagonia, Argentina) since the year 2000. This program surveys an extended shoreline, with bays and gulfs with shellfish natural banks and farms. Paralytic shellfish poison (PSP)-toxin-producing species, A. tamarense, have been observed during the study period; in addition, species producing diarrheic shellfish poison (DSP)-toxins, such as Dinophysis acuminata and D. tripos and Prorocentrum lima, and amnesic shellfish poison (ASP)-toxins, as several species of genus Pseudo-nitzschia, have been identified. Moreover, the production of the three types of toxins has been proven. Other harmful but nontoxic species have been registered in the area. The aim of this review is to show the temporal and spatial distribution of harmful microalgae species, the environmental factors associated with their occurrence, and their relation to toxic outbreaks during more than 15 years of observations, with special attention focused on the episodes of human intoxications. In addition, we discussed the accumulation and transfer of some phycotoxins through pelagic food webs, from the first trophic levels to large marine mammals, such as whales.
Aquatic Ecosystem Health & Management, 2017
Large nuisance blooms of Didymosphenia geminata have become increasingly widespread in Patagonia.... more Large nuisance blooms of Didymosphenia geminata have become increasingly widespread in Patagonia. Although the first published account for South America was in 1964, reports of large growths in Chile and Argentina commenced around 2010. Since then, these blooms have been observed all along the Andes region to the south of parallel 42°S. General surveys are needed to help provide an explanation. Possibilities include one or more new genetic variants or responses of local populations to global environmental changes. Electron microscopy of material from the Argentinean Patagonia revealed marked differences between regions, though it is unclear how much local factors and/or variations in life cycle contribute. Thus, we are approaching the problem from a molecular perspective, which we hope will help to overcome this limitation. Initial studies showed that D. geminata seems to be highly recalcitrant to DNA extraction, thus hindering the survey of molecular markers. We have now developed ...
Boletín de la Sociedad Argentina de Botánica, 2016
Morfología valvar de Didymosphenia geminata (Bacillariophyceae) en la provincia de Chubut, Argent... more Morfología valvar de Didymosphenia geminata (Bacillariophyceae) en la provincia de Chubut, Argentina. Recientemente se verificó que Didymosphenia forma proliferaciones masivas en Patagonia.En Argentina se ha esparcido a cinco provincias en un corto tiempo. En este trabajo, analizamos datos morfológicos y morfométricos de especímenes recolectados en la provincia del Chubut, Argentina y los comparamos con otras especies de este género de diferentes regiones del mundo. El material de estudio fue recolectado en dos cuencas durante 2010-2012. Las muestras, analizadas con MO y MEB, mostraron variación inter e intra-poblacional en las características morfométricas y en algunas estructuras valvares, como espinas. La morfología del material estudiado corresponde a la de D. geminata ssp geminata Metzeltin & Lange-Bertalot. Nuestros materiales también se asemejan a las especies: D. clavaherculis,D. clavamagna, D. coronata y D. laticollis. Los materiales de Chubut pueden ser fácilmente confund...
Boletín de la Sociedad Argentina de Botánica, 2019
Introducción y objetivos: Didymosphenia geminata, diatomea declarada “Especie Exótica Invasora” e... more Introducción y objetivos: Didymosphenia geminata, diatomea declarada “Especie Exótica Invasora” en Argentina por la Secr. Ambiente y Desarrollo Sustentable de la Nación. Esta especie coloniza rocas y puede formar grandes matas mucilaginosas que cubren el lecho de los ríos, ocasionando un considerable impacto estético y provocando serias alteraciones en los ecosistemas. En los últimos 9 años la especie ha colonizado ríos andino-patagónicos y ha aumentado considerablemente su distribución en la región. El objetivo de este trabajo es analizar la dinámica de esta especie en la Patagonia argentina mediante el uso de SIG.M&M: los datos provienen de resultados obtenidos por el grupo de trabajo en las provincias del Neuquén y del Chubut e información abierta y libre disponible en la web. Se generó una base de datos a escala regional abarcando desde Neuquén a Tierra del Fuego.Resultados: fueron incorporados a un SIG, lo que permitió generar mapas de distribución a nivel provincial y nacional...
Continental Shelf Research, 2018
Journal of Shellfish Research, 2015
Marine Mammal Science, 2015
Península Valdés (PV) in Argentina is an important calving ground for southern right whales (SRWs... more Península Valdés (PV) in Argentina is an important calving ground for southern right whales (SRWs, Eubalaena australis). Since 2005, right whale mortality has increased at PV, with most of the deaths (~90%) being calves <3 mo old. We investigated the potential involvement of harmful algal blooms (HABs) in these deaths by examining data that include: timing of the SRW deaths, biotoxins in samples from dead SRWs, abundances of the diatom, Pseudo‐nitzschia spp., and the dinoflagellate, Alexandrium tamarense, shellfish harvesting closure dates, seasonal availability of whale prey at PV and satellite chlorophyll data. Evidence of the whales' exposure to HAB toxins includes trace levels of paralytic shellfish toxins (PSTs) and domoic acid (DA) in tissues of some dead whales, and fragments of Pseudo‐nitzschia spp. frustules in whale feces. Additionally, whales are present at PV during both closures of the shellfish industry (due to high levels of PSTs) and periods with high levels o...
BioInvasions Records, 2013
Journal of Marine Systems, 2012