Extended Data Fig. 3: Heterogeneity of PAH composition in different environmental media.
From: Regionally distinct threats from polycyclic aromatic hydrocarbons in global reservoirs
Analysis of similarities (ANOSIM) was used to test the null hypothesis that PAH compositions do not differ signidicantly among environmental media. Correlations were evaluated using a two-sided, permutation-based test (999 permutations). The r statistic (effect size) and p-values are shown in the corresponding panels. y-axis indicates the degree of dissimilarity between and within groups. Boxplots display the distribution of rank dissimilarities: centre line = median, box = 25th–75th percentiles, whiskers = min/max within 1.5 times interquartile range (IQR), points beyond whiskers = outliers. Statistical significance is denoted as “*” for p < 0.05 and “**” for p < 0.01. For Loskop Reservoir, sediment (n = 18, N = 9) and water (n = 16, N = 9) samples were collected from nine sites during flood and storage seasons; for Blachownia, sediment (n = 5, N = 4) and water (n = 20, N = 4), and for Cedara, sediment (n = 4, N = 4) and water (n = 4, N = 4) samples were collected across seasons. Each n denotes an independent field sample (biological replicate). PAH concentrations were meansured in triplicate (technical replicates), and mean values were used for analyses.
