Abstract

MARTINEZ-GAXIOLA, MD; DURAZO, R  and  GAXIOLA-CASTRO, G. Influence of the geostrophic transport of phosphates on primary production off Baja California (Mexico). Cienc. mar [online]. 2010, vol.36, n.2, pp.135-145. ISSN 0185-3880.

We estimated the net flux of inorganic phosphorus (kg P d^-1) due to geostrophic transport in the upper 100 m of a control volume (CV) off Baja California (Mexico) during 2003 and 2004. The influence of this flux on integrated primary production (IPP) in the photic zone (<100 m depth) was estimated comparing the net P flux into the CV against the P requirements for IPP. The greatest P fluxes occurred during spring and summer 2004; the northern side of the CV was the main recipient of P. The most persistent P outflow occurred along the southern side of the CV, except in winter 2003, when there was an input of P fluxes related to cyclonic and anticyclonic eddies off Ensenada. The net geostrophic transport during 2003 and 2004 contributed enough P to support the IPP requirements during winter and spring, indicating that P was not limiting for phytoplankton organic carbon production during these seasons.

Keywords : phosphorus; geostrophic transport; primary production; Baja California; California Current.