Results of circumpolar assessment of river diatoms, indicating (a) the location of river diatom stations, underlain by circumpolar ecoregions; (b) ecoregions with many river diatom stations, colored on the basis of alpha diversity rarefied to 40 stations; (c) all ecoregions with river diatom stations, colored on the basis of alpha diversity rarefied to 10 stations; (d) ecoregions with at least two stations in a hydrobasin, colored on the basis of the dominant component of beta diversity (species turnover, nestedness, approximately equal contribution, or no diversity) when averaged across hydrobasins in each ecoregion. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 36 - Figure 4-8

Summary of the taxa accounting for 85% of the river benthic macroinvertebrates collected in each of several highly-sampled geographic areas, with taxa grouped by order level or higher in pie charts placed spatially to indicate sampling area. Pie charts correspond to (1) Alaska, (2) western Canada, (3) southern Canada, south of Hudson Bay, (4) northern Labrador, (5) Baffin Island, (6) Ellesmere Island, (7) Greenland high Arctic, (8) Greenland low Arctic, (9) Iceland, (10) Svalbard, and (11) Fennoscandia. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 70 - Figure 4-34

Figure 3-5 Changes in alpha diversity (red line), predator body size (blue dashed line), and ecosystem metabolism (blue solid line) with a shift in glacial cover from high (left) to low (right). Redrawn from Milner et al. (2017). State of the Arctic Freshwater Biodiversity Report - Chapter 3 - Page 22 - Figure 3-5

Figure 3-1 Long-term trends in ice duration (as days) in the River Torne (upper plot) and Lake Torneträsk (lower plot) at 68° north on the Scandinavian peninsula. Lines show smooth fit. Data source: Swedish Meteorological and Hydrological Institute. State of the Arctic Freshwater Biodiversity Report - Chapter 3 - Page 19 - Figure 3-1

Phytoplankton percent composition by dominant classes across the three Arctic regions, using relative presence across stations calculated from from presence – absence data. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 48 - Figure 4-19

Box plot represents the homogeneity of assemblages in high Arctic (n=190), low Arctic (n=370) and sub-Arctic lakes (n=1151), i.e., the distance of individual lake phytoplankton assemblages to the group centroid in multivariate space. The mean distance to the centroid for each of the regions can be seen as an estimated of beta diversity, with increasing distance equating to greater differences among assemblages. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 48 - Figure 4-18

Box-plots of taxa richness (average per lake) by Arctic regions for rotifers (left) and crustaceans (right). Crustacean taxa are restricted to taxa within Calanoida, Cyclopoida and Cladocera. Samples with only a single taxon have been excluded. Boxes represent median and interquartile range. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 60 - Figure 4-27

Taxa accumulation curves for (left) lake surface sediment samples, and (right) stream scrapes across the sub-Arctic (blue), Low Arctic (green) and High Arctic (red) ABA Arctic zones. Dashed lines represent the bounds of the 95% confidence interval of the estimate. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 38 - Figure 4-11

Figure 4 15 Comparison of the relative abundance of select diatom taxonomic groups between core bottoms (pre-industrial sediments; x- axis) and core tops (modern sediments; y-axis) with a 1:1 line to indicate whether there were higher abundances in fossil samples (below red line) or modern samples (above red line). State of the Arctic Freshwater Biodiversity Report - Chapter 2 - Page 15 - Figure 2-1

Temporal patterns in % abundance of Atlantic salmon, brown trout, and anadromous Arctic charr from catch statistics in Iceland rivers monitored from 1992 to 2016, showing results from (a) west, (b) south, (c) north, and (d) east Iceland. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 81 - Figure 4-41