Uptake and release of phosphorus by phytoplankton in the Chesapeake Bay estuary, USA

✍ Scribed by J. L. Taft; W. R. Taylor; J. J. McCarthy

• Publisher: Springer-Verlag
• Year: 1975
• Tongue: English
• Weight: 1004 KB
• Volume: 33
• Category: Article
• ISSN: 0025-3162
• DOI: 10.1007/bf00394997

✦ Synopsis

The phytoplankton uptake and release rates for inorganic phosphate, dissolved organic phosphate and polyphosphate were estimated during 5 cruises on the Chesapeake Bay over a 9-month period. Phosphorus in all pools turned over in several minutes to 1OO h, and each soluble pool appeared to contain fractions which were metabolically useful to the phytoplankton. Maximal uptake rates (Vm) for orthophosphate ranged from 0.02 to 2.95 ~g-at P (l.h) -I with half saturation constants (K s ) between 0.09 and 1.72 ~g-at P 1 -I. At low soluble reactive phosphorus concentrations, the uptake rate of trace 32p orthophosphate was initially rapid, but declined after 15 to 60 min incubation. The data suggest that the initial uptake phase was dominated by exchange of 32po4~ for 31po4~ in the membrane transport systems whereas the subsequent phase represented the net incorporation of orthophosphate into phytoplankton cells.