Ecology of the burrowing amphipod, Pontoporeia affinis, in Lake Michigan / by Wayne Paul Alley.

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A Spearman rank correlation test was calculated for stations C-2
through C-7 in order to determine if there was a significant association
in the patterns of Pontoporeia abundance (Table 11). The results show
that these stations have similar patterns of seasonal variation, particularly when adjacent stations are consideredo
The seasonal patterns of amphipod abundance for the seven
stations of the C transect were next compared with the abundance patterns of their respective depth zones by the Spearman rank correlation
(Table 12). Although only stations C-2 and C-4 showed any significant
association with their respective depth zones, all the correlation coefficients were positive, which would indicate that, in general, the
seasonal fluctuations of Pontoporeia of the seven C stations were similar to the fluctuations of their respective depth zones.
TABLE 9. Spearman rank correlation coefficients indicating the degree
of association that occurred among the patterns of seasonal abundance
of Pontoporeia affinis for the four depth zones and all depths combined.
10-35 m 36-65 m 66-105 m >;105 m
36-65 m -. 085
66-105 m -,204 188
>105 m -.400.421 o429
All stations
sion.529.459*.119.415
combined
* Significant at 5%0