Diatoms are single-celled, photosynthetic organisms whose cell wall is made of amorphous, or opaline silica, much like glass. They inhabit both fresh and marine waters, and may live upon substrates, such as the benthos, other plants or animals, or they may float freely through the upper part of the water column in the regions which receive light from the sun. This latter life style is termed planktonic (from the Greek word planktos = wanderer, drifter).
In the sea, planktonic diatoms are abundant in the near-shore waters of the continental shelves, and in equatorial and Polar upwelling regions. Along with other members of the phytoplankton, they form the base of the food chain for much of the life in the sea. Over geologic time, their photosynthesis has contributed to the oxygen atmosphere of our planet, and their shells have accumulated to form siliceous sediments on the ocean floor. Accurate species identification is fundamental to the understanding of community dynamics, biogeochemical processes and ecosystem stability, and requires that contemporary references be available and accessable to scientists with a variety of backgrounds.
With funding from the National Science Foundation (1994-1997), we are preparing an up-to-date set of reference materials, the Diatom Flora Project, to aid in the accurate identification of marine planktonic diatoms in the waters of the Northeast, U.S. coastal region. This web site provides a checklist of taxa for this geographic region, verified by Hargraves & Rines.
This site was last modified on 1 December 2000.
This project was
initiated in conjunction with a Biotic
Surveys & Inventories grant
from the National Science Foundation
to Paul Hargraves
& Jan Rines,
at the Graduate School of Oceanography,
University of Rhode Island
Site development by Jan Rines - jrines@gsosun1.gso.uri.edu
Number of visits since 21 April 1998: