Seasonal and Inter-Annual Analysis of Chlorophyll-a and Inherent Optical Properties from Satellite Observations in the Inner and Mid-Shelves of the South of Buenos Aires Province (Argentina)

Abstract

Abstract:The aim of this study is to describe and understand the seasonal and inter-annual physical and biological dynamics of the inner and mid shelves of the Southwestern Buenos Aires Province (Argentina). We used chlorophyll-a (chl-a) concentrations and inherent optical properties (IOPs), derived from ocean color products between 2002 and 2010, as a proxy for the physical and biological parameters of interest. This study focuses on the absorption by phytoplankton, aph(443), particulate backscattering, bbp(443), and absorption due to dissolved and particulate detrital matter, adg (443), and chl-a derived from a multiband quasi-analytical algorithm (QAA). A regionalization based on the coefficient of variation and the Census X-11 method were applied to define regions and to analyze the inter-annual and seasonal variability of the ocean color parameters, with regards to climate OPEN ACCESSRemote Sens. 2015, 7 11822 variability. The coastal zone presents the highest values of chl-a with two maxima in winter and autumn, while the mid-shelf shows a strong spring chl-a maximum. After 2009, all parameters under study shifted their seasonality and their magnitude changed over the entire area. In the coastal zone, mean values of aph(443) and bbp(443) increased, while in the mid-shelf, chl-a and aph(443) decreased. The observed inter-annual and seasonal behavior of the parameters is tightly related to climate variability of the study area.

Medusae and ctenophores from the Bahía Blanca Estuary and neighboring inner shelf (Southwest Atlantic Ocean, Argentina)

“…ER, in the adjacent shelf, extends to the 50 m isobath (Acha et al 2004). Within the ER area, low-salinity waters and sediments from the continent (Río Negro, Río Colorado and BBE), highly saline waters from the south (San Matías Gulf ) and shelf waters of typically intermediate salinity combine to create oceanic fronts and circulation cells that favor retention mechanisms, creating an appropriate environment for successful larval fish development (Hoffmeyer et al 2009;Acha et al 2012;Delgado et al 2015). Sandy beaches of MH and Pehuen Có are one of the most visited touristic destinations of Argentina (Vaquero et al 2007).…”

Influence of Physical-Biological Variability and Legal Regulations on Fisheries Resources in the Southern Coastal Zone of Buenos Aires Province, Argentina

“…La interacción entre el mar y la atmósfera generan el hábitat particular donde las especies viven, se alimentan y reproducen. El Rincón es un área costera compleja por las diferentes interacciones que se evidencian entre el continente y el mar, principalmente a través de las abundantes descargas de ríos, sumado a la susceptibilidad del sistema a la variabilidad climática (Delgado et al, 2015). Las fluctuaciones climáticas generan cambios en la composición física y química del agua (salinidad y sedimentos en suspensión) alterando en principio la base de la cadena trófica marina (fitoplancton) y directa o indirectamente al zooplancton y las comunidades pelágicas (Delgado et al, 2015).…”

“…Los estudios publicados indican que existe una relación importante entre la captura de especies en una región y las anomalías climáticas que se observan. Delgado et al (2015) asociaron la presencia de fitoplancton con la variabilidad climática del área de estudio (eventos ENSO). Se observo que el evento El Niño 2002 y La Niña 2008 generaron importantes cambios ambientales en las aguas costeras y de plataforma media, asociados a periodos húmedos-secos.…”

“…Los vientos predominantes de la zona (N-NW) llevaron este sedimento al ambiente marino originando un aumento de la turbidez del agua. Los cambios ambientales causaron alteraciones en la cantidad y estacionalidad de la distribución de la clorofila-α (utilizado como proxy de fitoplancton), base de la cadena ecológica marina y posiblemente en la presencia de peces (Delgado et al, 2015).…”

Preface: Remote Sensing of Water Resources

“…Delgado et al [7] conducted seasonal and inter-annual analysis of chlorophyll-a and inherent optical properties (IOPs) from MODIS derived ocean color products between 2002 and 2010 for the inner and mid shelf waters of the Southwestern Buenos Aires Province, Argentina. The inter-annual and seasonal variability of the ocean color parameters of the regions identified based on the coefficient of variation and the Census X-11 method revealed remarkable linkage between the climate variability and the IOPs which could be considered as proxies of the biological and physical parameters of the region.…”