| Resumo: |
El aporte de esta investigación, será dar una evaluación sobre la distribución cuali-cuantitativamente del fitoplancton y paralelamente iniciar una base de datos en 5 bahías de las Islas Galpagos.
The investigations of chlorophylls, cell counts, and qualitative or indicators species (net 50u), were presented, that used simultaneously provide valuable ecological information on the community of the phytoplankton accomplished in five bays: Bahia Naufragio (San Cristóbal Island), B. Pto. Velasco Ibarra (Floreana island), B.Villamil (Isabela Island), B. Academia (Santa Cruz Island), B. Darwin (Genovesa Island), during September- October/1999. Biomass in weight (chlorophyll "a") of 0.560 mg/m³ corresponds to a cellular biomass of 403.628 cel/l, with a relationship of 1.1, with exception of the area of upwelling in Isabela that was 1.3 (1.546 mg/m³: 5405.123 cel/l). 71 species were identified in water samples and 132 species in net samples (50u) in the community of the phytoplankton on each Island. The diatoms were dominant and the Dinoflagellates, Tintínnidos, Cocolitofóridos, Cyanophytas, Microflagellates and Ciliados were found in a low concentration. In cell counts Thalassiosira subtilis and Gymnodinium sp., were the species of high occurrence in all the bays, except for Isabela wich presented a bloom of Chaetoceros curvisetus. In net samples (50u), on Isabela Island and Floreana Island indicators species of upwelling were registered, among them we found: Corethron criophilum, C. curvisetus, Thalassiosira, subtilis, Gymnodinium sp.; On San Cristóbal y santa Cruz the species diversity evidenced a mixture zone mainly with species of tropical warm conditions as Ceratocorys horrida, Blepharocysta splendor, C. tripos, C. trichoceros, C. deflexum, C. contortum, C. vultur, C. massiliense, C. strctum, Dinophysis caudata, D. forthii, D. doriforum, Ornithcercus steinii, O. magnificus, Goniodoma polyedricum, Gonyaulax sp. The distribution of species presented a particular characteristic for each bay. Furthermore, some benthic species were observed wich are indicators from strong turbulence zones in the water column. As a general rule for the season between september and october of 1999, was observed a good biological productivity associated with the current of Cromwell with light indicator toward the next seasonal change, probably by local and extra regional process influence of the climate conditions.
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