Characteristics of the phytoplankton on the Peruvian sea. Summer 2014, Cruise 1402-04.

Abstract

We present volumes on plankton, distribution and phytoplankton composition, as well as biological indicators of water masses for the summer, from 65 samples collected with standard network of phytoplankton during survey cruise for pelagic resources 1402-04 aboard the R/V Olaya. Off Malabrigo and San Juan, the mean volume of plankton was 0.54 mL.m-3, the range varied between 0.27 and 1.4 mL.m-3 located off Malabrigo and San Juan, respectively. The dominance of the phytoplankton was 37%, formed by intermediate phase diatoms of succession and upwelling species that stood out such as Coscinodiscus perforatus, Skeletonema costatum, Detonula pumila, Actynocyclus sp., Chaetoceros spp., Thalassiosira angulata, Lithodesmium undulatum, Rhizosolenia styliformis and Odontella aurita. The displacement of SSW towards the coastal zone was evident due to the great richness of species belonging to this type of water. Ceratium breve, indicator of ESW, was registered normally until Punta La Negra (60 nm) and Protoperidinium obtusum, indicator of CCW, was restricted to the coastal strip (30 nm). The algal flowering of Mesodinium rubrum was observed from Huarmey to Huacho whose maximum concentration was 73x106 cel.L-1.