JOURNAL OF PLANKTON RESEARCH | VOLUME 1 | NUMBER 3 | PAGES 241-265 | 1979
© Oxford University Press
research-article |
Monterey Bay phytoplankton I. Seasonal cycles of phytoplankton assemblages
University of California. Center for Coastal Marine Studies Division of Natural Sciences, Applied Sciences Building Santa Cruz, California, 95064, USA
Received on July 1, 1979; accepted on September 1, 1979 Netplankton collections from shallow-water stations in Monterey Bay, California were examined for 1976 and 1977. The predominating phytoplankton forms were neritic diatom species. Recurrent species groups were identified using Fager's regroup analysis and their distributions related to hydrographic seasons. Neritic groups were relatively more abundant during the Davidson Current and upweiling periods; however, many of the species were present throughout much of the year. The appearance of oceanic groups and species was seasonal and associated with advective events.
One neritic species group was of overwhelming numerical importance but within the group conspicuous changes in relative abundance of phytoplankton populations occurred seasonally among species from this group. This group appears to be composed of resident species and may be locally retained as vegetative cells or benthic resting stages. Species cycles in Monterey Bay may be regarded as largely the result of suc-cessional changes or cycles of autochthonous species, while species introduced by adjective processes appear to be of minor importance.
The study has suggested that the presence of species in a ‘seed population’, either as vegetative cells or benthic resting stages, may be important as the growth rate of the species in understanding and predicting composition and relative abundance in coastal phytoplankton assemblages.