Premium
IN SITU UPTAKE KINETICS OF AMMONIUM AND PHOSPHATE AND CHEMICAL COMPOSITION OF THE RED SEAWEED GRACILARIA TIKVAHIAE 1
Author(s) -
Friedlander Michael,
Dawes Clinton J.
Publication year - 1985
Publication title -
journal of phycology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.85
H-Index - 127
eISSN - 1529-8817
pISSN - 0022-3646
DOI - 10.1111/j.0022-3646.1985.00448.x
Subject(s) - phosphate , ammonium , biology , nutrient , gracilaria , carbohydrate , saturation (graph theory) , phycoerythrin , algae , composition (language) , botany , zoology , food science , biochemistry , chemistry , ecology , microbiology and biotechnology , flow cytometry , mathematics , linguistics , organic chemistry , philosophy , combinatorics
ABSTRACT The uptake kinetics of ammonium and phosphate by Gracilaria tikvahiae McLachlan were studied under field conditions. Seaweeds, pulse fed once a week for 6 h over a 4‐week period, had maximum uptake rates of 19 μmol·g fwt −1 ·h −1 for ammonium and 0.28 μmol·g fwt −1 ·h −1 for phosphate. For both nutrients there was a positive linear correlation between uptake rate (v) and concentration (S) over the entire range of concentration tested. In a nutrient depletion experiment, the phosphate uptake curve determined over a wide range of concentrations consisted of two stages of saturation at low concentrations, and a linear phase at high concentrations. Ash free dry weight, chlorophyll a, phycoerythrin, and protein content were higher in pulse fed plants than in control plants receiving no nutrient additions, while the reverse held true for carbohydrate contents and the C/N ratios. The C/N ratio inversely correlated with ammonium and phosphate uptake rate as well as protein and phycoerythrin content, and positively with carbohydrate content.