FIG. 5.

CCA ordination plots for the first two principal dimensions of the relationship between the sediment and porewater environmental parameters in Jiaozhou Bay and the distribution of the sediment anammox bacterial assemblages as reviewed by assessing the “Ca. Scalindua” 16S rRNA gene OTUs (a) or the anammox bacterial Hzo OTUs (b). Correlations between environmental variables and CCA axes are represented by the length and angle of arrows (environmental factor vectors). Due to the possible diel variation of seawater temperature, DO, and pH during our sampling period, these parameters were not included in the analyses. Covarying variables, such as NH₄⁺ and dissolved inorganic nitrogen (DIN) (r = 0.9969) and OrgC and OrgN (r = 0.9826), were checked to minimize collinearity in the CCA analyses.