Definition: A cell shape that approximates a sickle-shaped prism. Sun, J. and Liu, D. 2003. Geometric models for calculating cell biovolume and surface area for phytoplankton, J. Plankton Res., 25, 1331–1346, doi:10.1093/plankt/fbg096, Table II
Definition: Siliceous ooze is a marine sediment composed of the debris of plankton with silica shells, such as diatoms and radiolaria. This ooze is limited to areas with high biological productivity, such as the polar oceans, and upwelling zones near the equator. The least common type of sediment, it covers only 15% of the ocean floor. It accumulates at a slower rate than calcareous ooze: 0.2-1 cm / 1000 yr.
Definition: A habitat that is in or on a body of water containing low concentrations of dissolved salts and other total dissolved solids (<0.5 grams dissolved salts per litre).
