Original paper
Bacterioplankton nutrient deficiency in a eutrophic lake
Wang, Lizhu; Miller, Thomas D.; Priscu, John C.
Archiv für Hydrobiologie Volume 125 Number 4 (1992), p. 423 - 439
36 references
published: Oct 19, 1992
DOI: 10.1127/archiv-hydrobiol/125/1992/423
ArtNo. ESP141012504002, Price: 29.00 €
Abstract
The time-course response of bacterioplankton and phytoplankton to enrichment with NH4+, PO4-3, and mannitol (singly and in various combinations) were measured over two years during June, August, and October in a north-temperate, eutrophic lake. Bacterial cell concentration and activity (3H-thymidine incorporation) increased significantly (p < 0.05) with addition of po4-3 in June, additions of PO4-3 NH4+, and mannitol in August, and addition of mannitol in October, 1988. In these same experiments, phytoplankton biomass (chlorophyll-a) and activity (14CO2 uptake) increased significantly (p < 0.05) with addition of po4-3 in June; 14CO2 uptake increased significantly (p < 0.05) with additions of nh4 + in August and October. During 1989, bacterial cell concentration and activity increased significantly (p < 0.05) with most nutrient additions, except po4-3 in June, which showed no stimulation. Concomitantly, the addition of NH4+ in June, and NH4+ and PO4-3 in August significantly (p < 0.05) increased 14CO2 uptake and chlorophyll-a during the 1989 experiments. Inorganic nutrient enrichments appeared to stimulate bacterial activity both directly and indirectly via phytoplankton products. Our results lead us to contend that inorganic nutrients may be as important as organic nutrients in the regulation of bacterioplankton growth in certain aquatic environments.
Keywords
bacterioplankton • phytoplankton • chlorophyll-a