Phytoplankton Composition and Distributions in Waldo Lake, Oregon

ABSTRACT

The phytoplankton community in Waldo Lake, Oregon is unusual for several reasons, including: (1) phytoplankton diversity is extremely low, with the dinoflagellate Glenodinium neglectum comprising more than 75% of the total phytoplankton; (2) phytoplankton densities are extremely small, with total density and total biovolume averaging 57 algal units ml⁻¹ and 18.5 X 10³ μm³ ml⁻¹, respectively; (3) phytoplankton abundance and species composition are nearly uniform throughout the water column, surface to 120 m; (4) several phytoplankton taxa are rare, and some may be new species that have not yet been identified; and (5) picoplankton, which are abundantly present, may be important contributors to the lake's primary production.

Key Words:

• phytoplankton
• limnology
• Waldo Lake
• ultraoligotrophic lakes
• dinoflagellates
• picoplankton