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

4000
3000
2000
1000
-j
I O..J
-J,2000
-d
z
1000

o INSHORE STATIONS
o OFFSHORE STATIONS

<

N

-L

~~r.4A

L

AM J J A S 0 N 'A M J J A S OA M J J A S O
1972 1973 1974
FIG. 2. Mean numbers of cells per ml and standard
errors of phytoplankton collections at stations of the
Cook Plant minimal survey grid, 1972 through 1974.
generally lower than inshore during the intervening months.
To ascertain whether the suggested seasonal (or bi-seasonal) differences
between inshore and offshore numbers of forms were present in other years,
Table 5 was constructed. It presents the monthly mean numbers of forms at
inshore and offshore stations in 1972, 1973, and 1974; in addition it gives
the 3-year grand mean of form numbers.
On the basis of the present three years of monthly data, the grand means
indicate similar numbers of forms at inshore and offshore stations in April
and May and again in the fall (though the latter is based on a single set of
November data). Substantially fewer forms have been collected at offshore
stations in the period June through October.

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