Variabilidad espacial y temporal del fitoplancton antártico en aguas adyacentes a las Islas Shetland del Sur, Antártica
Date
2013
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Universidad Austral de Chile
Abstract
La comunidad fitoplanctónica es la base de la trama trófica del océano Austral y es
la principal fuente de producción primaria y biomasa autótrofa en la región Antártica. El objetivo de esta tesis fue estudiar la variabilidad interanual (2004-2007) de los ensambles fitoplanctónicos en un gradiente costa-océano en las aguas adyacentes a las Islas Shetland del Sur, Antártica. Las muestras fueron recolectadas durante el mes de Febrero a través del programa Antártico AMLR-USA, entre los años 2004 al 2007. Las muestras se colectaron a 5 m de profundidad utilizando botellas Niskin y fueron cuantificadas en términos de abundancia y análisis de taxas utilizando microscopia. Se estudiaron tres Grupos Fitoplanctónicos: Nanoflagelados,
Dinoflagelados y Diatomeas Céntricas y Pennadas. El grupo de Nanoflagelados fue
el que presentó las mayores abundancias durante los cuatro años de estudio, con
una contribución de un 32% en estaciones oceánicas (2005) hasta un 98,1% en las
estaciones costeras (2007). El año 2005 se registraron las menores concentraciones
de células fitoplanctónicas en las estaciones estudiadas (10.146 cél/L estación
costera y 3500 cél/L estación oceánica), mientras que el 2006 se registraron las
mayores concentraciones (15.954.937 cél/L estación costera y 17.714.222 cél/L
estación oceánica). Durante los veranos se observó una segregación de los grupos
en el gradiente océano-costa, con una mayor contribución de Nanoflagelados en las
estaciones costeras y de Nanoflagelados y Dinoflagelados para la región oceánica.
The phytoplanktonic community is the base of the trophic plot of the Austral Ocean and it is the main source of primary production and autotrophic biomass at the antarctic region. The purpose of this work was the studying of year-on-year variability (2004-2007) of phytoplanktonic assemblies in a coast to ocean gradient, at the waters adyacentes to Shetland del Sur Islands, Antarctic. Samples was collected during February through the Antarctic Program AMLR-USA, between 2004 and 2007. Samples was collected at 5 meters depth using niskin bottles and it was quantified in terms of abundance and taxonomic analysis using microscope. Three phytoplanktonic groups was studied: Nanoflagellates, Dinoflagellates and Diatoms centric and pinnate. The Nanoflagellates group showed higher abundances during the four years study, with a contribution from 32% in oceanic stations (2005) to 98,1% in coastal station (2007). In 2005 the lower concentrations was registered, for the phytoplankton cells studied as for stations (10.146 cel/Liter at coastal station and 3.500 cel/Liter at oceanic station), meanwhile in 2006 the higher concentrations was registered (15.954.937 cel/Liter at coastal station and 17.714.222 cel/Liter at oceanic station). During the summer there was a segregation of groups in the gradient ocean area, with a greater contribution of Nanoflagellates in the coastal stations and Nanoflagellates and Dinoflagellates to the oceanic region.
The phytoplanktonic community is the base of the trophic plot of the Austral Ocean and it is the main source of primary production and autotrophic biomass at the antarctic region. The purpose of this work was the studying of year-on-year variability (2004-2007) of phytoplanktonic assemblies in a coast to ocean gradient, at the waters adyacentes to Shetland del Sur Islands, Antarctic. Samples was collected during February through the Antarctic Program AMLR-USA, between 2004 and 2007. Samples was collected at 5 meters depth using niskin bottles and it was quantified in terms of abundance and taxonomic analysis using microscope. Three phytoplanktonic groups was studied: Nanoflagellates, Dinoflagellates and Diatoms centric and pinnate. The Nanoflagellates group showed higher abundances during the four years study, with a contribution from 32% in oceanic stations (2005) to 98,1% in coastal station (2007). In 2005 the lower concentrations was registered, for the phytoplankton cells studied as for stations (10.146 cel/Liter at coastal station and 3.500 cel/Liter at oceanic station), meanwhile in 2006 the higher concentrations was registered (15.954.937 cel/Liter at coastal station and 17.714.222 cel/Liter at oceanic station). During the summer there was a segregation of groups in the gradient ocean area, with a greater contribution of Nanoflagellates in the coastal stations and Nanoflagellates and Dinoflagellates to the oceanic region.
Description
Tesis para optar al Título de Ingeniero en Acuicultura
Keywords
Ciencia, Islas Shetland del Sur, South Shetland Islands, Fitoplancton