Producción primaria, biomasa y composición taxonómica del fitoplancton costero y oceánico en el Pacífico colombiano (septiembre-octubre 2004)

Abstract

Quantitative and qualitative studies of the phytoplankton community were carried out at two coastal and two oceanic stations in the Colombian Pacific. The 43 species identified in the study area included 19 diatoms and 24 dinoflage- llates. The average diversity values were greater at the coastal (2.89 bits·cel -1 ) than at the oceanic (1.42 bits·cel -1 ) stations. The same was true of primary production, with estimated values of 155.87 (coastal) and 60.50 mgC·m -2 ·h -1 (oceanic). The chlorophyll-a concentration fluctuated between 11.37 and 32.35 mg·m -2 , as an integrated value in the frictional influence zone (0-50 m depth). A positive correlation was found for primary production with species diversity (r = 1.0) and with the nitrite concentration (r = 0.8), whereas the reverse was found with the phosphate concentration (r = -1.0). These results represent the first attempt to estimate primary production in the oceanic waters of the Colombian Pacific basin, providing a starting point for other such studies in this area.