ISSN:
1432-1793
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Primary productivity and the flux of DO14C, dissolved saccharides (DSAC) and dissolved free primary amines (DFPA) were followed in the Sargasso Sea, Caribbean and upwelling waters of Peru. Average carbon fixation rates were 42.8, 292.8 and 4791.6 mg C m-2 d-1, respectively, with nocturnal respiration rates ranging from 9.8–16.3% of gross photosynthesis for the 3 areas. The release of DO14C, as a percentage of the total carbon fixed in photosynthesis, was non-detectable in the Sargasso Sea, and 3.2 and 4.4% for the Caribbean and Peruvian phytoplankton communities. Few significant changes in DSAC concentrations were recorded over a 36-h incubation period in the Sargasso Sea and Caribbean stations, whereas light-dependent accumulations of DSAC and DFPA were noted in Peruvian stations which were strongly correlated with total phytoplankton productivity. In the Peruvian stations, the average accumulation rate was 234 mg DSAC-C m-2h-1 while the average rate of nocturnal decomposition was 141 mg DSAC-C m-2h-1; diurnal and nocturnal rates of DFPA accumulation and decomposition were similar (2 mg DFPA-C m-2h-1). These data were used to calculate bacterial production in the upwelling waters of Peru. A general discussion of 14C-technique and routine analytical techniques for DSAC analysis is presented, as DSAC flux exceeded DO14C flux by 17-fold in coastal Peruvian stations.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00397073
