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

Phytoplankton Summary Tables

The phytoplankton summary tables employed here are based on the ones
used by the Michigan Water Resources Commission at the time our reporting
procedures were established (MWRC, 1970). Our summaries differ from theirs
in that we count the numbers of cells in filamentous and colonial forms
(except blue-green algae with cylindrical trichomes which are counted as
individual organisms), while the Commission counts a filament or colony as a
single organism. The station collection records from which the summaries for
1977 were prepared constitute Appendix B.
The summary table for each seasonal survey presents, station-by-station,
the surface-water temperature at the time of collection, the numbers per ml
of each of ten major categories of planktonic algae, and the dominant (and
codominant, see below) species or groups. The categories of phytoplankton
employed are: coccoid blue-green algae, filamentous blue-green algae,
coccoid green algae, filamentous green algae, flagellates, centric diatoms,
pennate diatoms, desmids, other algae, and total algae. The summary tables
allow quick assessment of the general compositions of the populations
sampled, the ambient water temperature, and give the dominant and codominant
species or groups (forms). The summary tables presented in Table 2 cover the
surveys of spring (April), summer (July), and fall (October) of 1977.
Dominant and Codominant Phytoplankters
In each phytoplankton sample one form (species or group) is typically
present in greater abundance than the others. We designate these species or
groups as "dominant." In many samples, however, one or more other species or
groups will come close to matching the numbers of the dominant form; we

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