Premium
INTERACTIONS BETWEEN LIGHT, NH 4 + , AND CO 2 IN BUOYANCY REGULATION OF ANABAENA FLOS‐AQUAE (CYANOPHYCEAE) 1
Author(s) -
Spencer Craig N.,
King Darrell L.
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.0022-3646.1985.00194.x
Subject(s) - buoyancy , anabaena , eutrophication , algae , cyanobacteria , biology , irradiance , environmental chemistry , algal bloom , microcystis , botany , phytoplankton , ecology , chemistry , nutrient , physics , thermodynamics , optics , genetics , bacteria
Buoyancy of the gas‐vacuolate alga Anabaena flosaquae Brébisson was measured under various levels of light, NH 4 + , and CO 2 . At high irradiance (50 μE · m −2 · −1 ) the alga was non‐buoyant regardless of the availability of CO 2 and NH 4 + . At low irradiance (≤10 μE · m −2 · s −1 ) buoyancy was controlled by the availability of NH 4 + and CO 2 . When NH 4 + was abundant, algal buoyancy was high over a wide range of CO 2 concentrations. In the absence of NH 4 + , algal buoyancy was reduced at high CO 2 concentrations, however as the CO 2 concentration declined below about 5 μmol · L −1 , algal buoyancy increased. These results help explain why gas vacuolate, nitrogen‐fixing blue‐green algae often form surface blooms in eutrophic lakes.