Photosynthetic activities of phytoneuston and phytoplankton.

Numbers, biomasses, and photosynthetic activities of phytoneuston and phytoplankton of near-surface microlayer and associated sub-surface waters, respectively, of coastal British Columbia were compared. Microalgal numbers, biomasses, and photosynthetic activities were generally greater in the sub-surface waters. Photosynthetic activities per unit biomass of the phytoneuston were approximately two-thirds those of the phytoplankton. These data suggest that the phytoneuston are injured or inhibited in some manner in near-surface microlayer waters.