To verify potential correlations between farms, Spearman
rank correlation analysis (Zar, 1990) was performed
at a = 0.05. One-way Kruskall–Wallis ANOVA (Zar,
1990) was used to test for significant (a = 0.05) effects of
the factors ‘‘station”, ‘‘campaign”, and ‘‘farm” on the
phyto- and zooplankton data from all farms. No effect of
the factor ‘‘State” was tested as Ceara´ State had eight of
the 14 farms. These analyses were performed with STATISTICA
5.1 (StatSoft Inc.).