Aquatic Sciences Meeting, Albuquerque 2001

CS41 Phytoplankton: Nutrient Dynamics and Physiology

Date: Friday, February 16, 2001, Time: 9:15:00 AM

Location: Galisteo

Hinga, K, R, University of Rhode Island, Graduate School of Oceanography, Narragansett, RI, USA, khinga@gso.uri.edu

pH VARIABILITY IN COASTAL WATERS AND pH EFFECTS ON PHYTOPLANKTON

The pH in typical coastal environments may vary 1 to 2 pH units. This is far greater than the range of pH expected from alkalinity variability. The primary cause of the pH variability is respiratory-driven removals and additions of dissolved Total CO2. The magnitude of pH variability is increased by eutrophication. Phytoplankton growth rates, for most studied species, are sensitive to pH changes in the pH range observed in coastal waters. Different species have maxima in growth rate ranging from pH 6.3 to 9.3. This suggests that seawater pH should, at least on occasion, be a factor in the ecology of coastal marine phytoplankton. The effects of pH could be quite important at the relatively rare extremes of pH, and contribute to the dynamics harmful algae bloom species. Further, many species may be significantly influenced by changes in pH near the normal pH of coastal seawaters.

This Session Listing

Aquatic Sciences Meeting, Albuquerque 2001

Quicklinks