highly significantp < 0.01
The differences comparison analyses (between indicators in zones with macrophyte coverage and void of macrophyte, and between indicators in different seasons) were analyzed by Wilcoxon signed rank test of non-parametric test with SPSS 13.0 software, and significance levels reported as not significant (p ≥ 0.05), significant (0.01 ≤ p<0.05) or highly significant (p < 0.01).