Ecologie des foraminifères planctoniques du golfe de Gascogne ...

tel-00480660, version 1 - 4 May 2010
Chapitre II
Figure II-5: Standing stocks of living planktic foraminifera per cubic meter of seawater at Stations
WH, A, B, and D, from March to November.
6.2. Distribution of cytoplasm bearing tests in relationship to environmental
parameters
In general, the abundance of living PF in surface waters was related to chlorophyll-a
concentration and sea surface salinity (Fig. II-4). On a regional scale, highest abundance of
living PF at offshore Station WH in April, at Station A in March and at onshore Station D in
November (Fig. II-4), was positively related to surface water chlorophyll-a concentration
(Fig. II-8). During March, April and June, maximum PF abundance occurred at water depths
of maximum chlorophyll-a concentration (Fig. II-4). At times and locations of strongly
decreased sea surface salinity (50% of the total fauna >100 µm) at the
three deep-water Stations WH, A, and B during March, April, July, and November (Fig. II-6).
In June, small specimens (100-150 µm) were overall much less frequent than during the other
sampled months with a minimum of 13% of the total fauna >100 µm at Station WH. In
general, small specimens were least abundant at shelf-break Station D, with a minimum of
18% in April.
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