Variability of the phytoplankton community in autumn 2007. Cruise 0705-06

Abstract

The cruise covered the area from Callao to Paita, up to 200 mn. A total of 21 samples were collected using phytoplankton net (75 μm). Zooplankton was more representative in the oceanic part while phytoplankton was within 30 nm. Chimbote was the place whose plankton biomass was the highest. La Niña event conditions seem to have influenced the distribution of indicator organisms, although the presence of Ceratium breve, an indicator of Surface Equatorial Waters (SEW), at 150 nm off Chimbote and Callao, showed delays from previous incursions. PCA showed that temperature was the parameter of greatest contribution of axis 1 and latitude was for axis 2. This analysis defined groups that coincided with the presence of a single water mass indicator.