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

Ayers (1978) explains the missing data and discusses the degrees of
similarity in population compositions at the two station groups. On the
whole, the temporal changes of the component parts of the phytoplankton
communities at the two station groups have been qualitatively similar in the
preoperational years; only in the flagellates and green algae in 1973 were
the changes directionally different in the two station sets. In the
operational years the compositional changes in the communities at the plant
and reference stations have been, if anything, even more similar than in the
preoperational period.
In both the plant and the reference stations in 1975 flagellates
represented a greater proportion of the population than in 1974, though not
so great a one as was observed in September-November 1970 and about the same
as in July 1972. As a result of the warmer summer, flagellates in both
station groups reached their greater abundances a month earlier than in 1974.
Green algae in both plant and reference stations began their greater
abundances in July 1975, again an effect of the warmer summer. In neither
station group did these algae reach the massive proportions of the
populations that were observed in 1971.
In 1976 the partitionings of the five components of the phytoplankton
populations were, in both the plant stations and the reference stations,
different from those observed in previous years. Blue-green and green algae
did not exhibit the pronounced maxima or minima of other years. Flagellates
in both station groups were generally a higher and more sustained proportion
of the population than in other years. Desmids and other algae peaked in
September, which had not been seen before. The summer diatom minimum
occurred in June in the plant stations and in June and July in the reference
stations; in both sets of stations the minima were less severe than in 1974

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