*2.5. Statistical Analyses*

The average values of (a) thirty eight physico-chemical parameters in the water column, surface sediments, and SPM collected monthly for one year in eight stations (1, 5, 8, 10, 12, 15, 16, and 17), (b) seven aquatic angiosperm variables: number, diameter, and growth of surviving sods and rhizomes, and (c) the results of the application of three indices of ecological status determined at the end of the sampling year were analyzed. The Shapiro–Wilk test differentiated non-normal data, and then Spearman's one-way ANOVA coefficients were calculated and summarized in Table 1. Significant values (*p* < 0.05) are marked in red.

**Table 1.** Spearman's non-parametric coefficients between sod/rhizome variables and physico-chemical parameters and nutrient concentrations in the water column and surface sediments. Significant values (*p* < 0.05) are in red. Legend:, Temp = water temperature, Transp = water transparency, Salin = salinity, %DO = percentage of dissolved oxygen, Eh = redox potential, w = water, s = sediment, Light-S = light at a depth of −5 cm, Light-B = light at bottom, FPM = filtered particulate matter, Si = silicates, RP = reactive phosphorus, NH4+ = ammonium, NO2− = nitrites, NO3− = nitrates, DIN = dissolved inorganic nitrogen, M-biom = macroalgal biomass, M-cover = macroalgal cover, Chl*-a* tot = total Chlorophyll-*<sup>a</sup>*, TP = total phosphorus, IP = inorganic phosphorus, OP = organic phosphorus, TN = total nitrogen, TC = total carbon, OC = organic carbon, SPM = settled particulate matter, part = particulate.


The principal component analysis (PCA) was applied to the same log-transformed data after removing redundancies to visualize the variances and associations between parameters, aquatic angiosperm variables, and index values of the eight stations. Results are reported in a bi-plot. Data were processed by Statistica software, release 10 (StatSoft Inc. Tulsa, OK, USA).
