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

standard errors are plotted on a time axis in Figure 7.
The plots in Figure 7 show visual evidence of a trend, beginning in 1973,
for redundancies to have become somewhat lower since that year. If real, the
trend would indicate that there has been a tendency for the species in the
community to have become more nearly equally abundant in numbers of individuals.
Perhaps more important is that after 1972 there has been much better
parallelism between the annual curves of redundancies at inner1 aa later
station groups, that is, changes in mean redundancies of collections from the
two station groups have been much more alike than was the case in the earlier
preoperational years. Since it began in the preoperational years and has
continued into the operational years, the tendency for improved parallelism is
attributed to some cause in the lake itself.
There is nothing in this analysis of phytoplankton redundancies to
indicate that the operation of Cook Plant has exerted any adverse impact on the
local phytoplankton community.
Inner-Outer Graphical Comparisons: Phytoplankton Abundances By Algal Categories
This section applies the inner-outer graphical analysis method to the
abundances (in cells per ml) of ten major categories of phytoplankton and
extends previously reported tabulations, figures, and discussions to include
the seasonal surveys of 1977. Earlier years have been reported by Ayers,
Southwick, and Robinson (1977) and Ayers (1978).
The phytoplankton abundances used are those of total algae and of the nine
major algal groups: coccoid blue-greens, filamentous blue-greens, coccoid
greens, filamentous greens, flagellates, centric diatoms, pennate diatoms,
desmids, and other algae. The use of major algal groups bypasses difficulties
stemming from inability to always identify to species, and is justifiable on

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