Phytoplankton of the seasonal surveys of 1977, and further pre- vs. post-operational comparisons at Cook Nuclear Plant / John C. Ayers, Susan J. Wiley.

or 1975. In general, it appears that in 1976 flagellates and desmids and
other algae increased at the expense of diatoms, coccoid and filamentous
greens, and blue-green algae in both the plant and the reference stations.
In 1977 blue-greens returned to the summer peak levels of 1974 and
1975. Green algae, in both sets of stations, were a minor part of the
population in each of the surveys. Flagellates weresomewhat more abundant
in spring 1977 than in the springs of preceeding years and had a May peak in
abundance at the expense of the diatoms. Diatom summer minima occurred in
August in each station set; a second minimum occurred in October at the plant
stations and in November in the reference stations. Desmids and other algae
peaked in September as they had in 1976. Except that the fall increase in
diatoms and decrease in blue-greens had begun in November at the plant
stations but not yet at the reference stations, the abundance changes in the
two sets of stations were directionally similar in 1977.
No dissimilarities attributable to plant operation have been revealed by
this method of analysis.
Inner-OutterGraphical Cormparisons: Numbers of Forms
In this section the term "forms" includes organisms identified to
species (e.g. Melosira Zranulata), organisms identified only to genus (e.g.
Ulothrix sp. or spp.), and composite groups of unidentified organisms (e.g.
Flagellates).
Data on the numbers of phytoplanktonic forms in collections from the
Cook Plant region in the years 1971 through 1975 have been presented and
discussed by Ayers, Southwick, and Robinson (1977); Ayers (1978) extended the
data and discussions to include 1970 and 1976; for the most part the
tabulated data in those reports are not repeated here. This section concerns

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