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Fig. 1 | Microbiome

Fig. 1

From: Microbial river-to-sea continuum: gradients in benthic and planktonic diversity, osmoregulation and nutrient cycling

Fig. 1

Plots showing variation in nutrient concentrations and community composition. a The Waiwera river sampling locations (1 to 9) with water column salinity gradient (0–35) shown using kriging interpolation. b Nutrient concentrations in sediment, sediment pore water and water samples taken in triplicate across the sampling sites. Grey background represents brackish sites (2.0–4.5 km along the transect). Abbreviations: TRP total recoverable phosphorus, TS total sulfur, TN total nitrogen, TOC total organic carbon, DRP dissolved reactive phosphorus, DNPOC dissolved non-purgeable organic carbon. Error bars represent standard errors of means. Asterisks (∗) indicate a significant difference between all water column and sediment samples (Wilcoxon p < 0.05). c Multivariate regression tree of microbial community abundance data associated with the environmental variables. Abbreviations: s salinity, NO2− nitrite, n sample size. Units: nitrite (g/m3). d NMDS ordination of small subunit rRNA gene sequences based on Bray–Curtis dissimilarities. Samples are coloured according to salinity. Environmental vectors were fitted onto the NMDS scores of the microbial community by the R-function envfit (p < 0.05, permutation = 999). e Distance–decay relationships of community dissimilarity (Bray–Curtis index) with increasing geographical distance. The regression lines were fitted to the data points using log generalised linear (GLM, solid line) and LOESS (dotted line) models. Each data point represents a pairwise comparison of samples from the water column (closed circles) or sediment (open circles)

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