The phytoplankton of the Cook Plant monthly minimal surveys during the preoperational years 1972, 1973, and 1974 / by John C. Ayers.

COOK INSHORE STATIONS VS. REFERENCE STATIONS, 1974

Beginning with April 1974, two reference (control) stations were added to
the Cook Plant monthly minimal surveys. These stations, NDC-7-1 and SDC-7-1,
are located seven miles north and south (respectively) of the plant. They are
designed to provide pre- and postoperational data, from inshore stations which
the plant's thermal plume is not expected to reach, for comparison with inshore
stations in front of the plant which the plant's plume is expected to reach all
or most of the time.
Table 9 compares the list of species and forms collected at the four inshore stations in front of the plant to similar lists from the two reference
stations. Species or forms collected only at offshore stations have been omitted. In the four Cook Plant inshore stations forms that totalled 100 cells per
ml or more collected during the seven months' surveys have been arbitrarily
termed "abundant" and annotated by (A). Because the offshore collections are
omitted from Table 9, the abundant forms of this table will not be the same as
those rated abundant in Table 1.
Because the Cook Plant inshore collections were from four stations while
the reference stations were single stations, the "abundant" rating was given
to any reference station form that attained 25 or more cells during the seven
surveys.
One form, Pandorina sp., from the north reference station was not annotated
"abundant" because it occurred in large numbers in one sample only and was not
present in any other.
A total of 249 forms is shown in Table 9; of these 124 were common to the
Cook inshore stations and one or both the reference stations. In most cases
these were the more abundant forms and the reference stations appear to be
adequately representative of the Cook stations for these forms.
In the rare forms, chance catches play a large part in the collections.
The Cook station collections showed 76 rare forms that were not taken at the
reference stations, but the two reference stations provided 49 rare species
that were not taken at the Cook stations. The four Cook stations were not
twice as productive of rare forms as the two reference stations.
Table 10 compares the Cook Plant inshore stations and the reference
stations by station and month. Both sets of stations exhibit wide variability,

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