Figure 4 17 Results of circumpolar assessment of lake phytoplankton,(a) the location of phytoplankton stations, underlain by circumpolar ecoregions; (b) ecoregions with many phytoplankton stations, colored on the basis of alpha diversity rarefied to 35 stations; (c) all ecoregions with phytoplankton 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 56 - Figure 4-17

Results of circumpolar assessment of lake zooplankton, focused just on crustaceans, and indicating (a) the location of crustacean zooplankton stations, underlain by circumpolar ecoregions; (b) ecoregions with many crustacean zooplankton stations, colored on the basis of alpha diversity rarefied to 25 stations; (c) all ecoregions with crustacean zooplankton 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 58 - Figure 4-25

Average relative abundance of the main zooplankton groups (calanoid copepods, cyclopoid copepods, cladocerans) for the sub-Arctic (n=150), low- Arctic (n=154), and high-Arctic (n=55) regions. Samples with a single taxon have been excluded. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 61 - Figure 4-28

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

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

Figure 2-2 Arctic freshwater boundaries from the Arctic Council’s Arctic Biodiversity Assessment developed by CAFF, showing the three sub-regions of the Arctic, namely the high (dark purple), low (purple) and sub-Arctic (light purple)

Figure 4-1 A generic food web diagram for a lake or river, indicating the basic trophic levels (boxes) and energy flow (arrows) between those levels. Reproduced from Culp et al. (2012a). State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 25 - Figure 4-1

Alpha diversity (± standard error) of river (a) diatoms from benthic samples, (b) benthic macroinvertebrates, and (c) fish within hydrobasins in western and eastern North America plotted as a function of the average latitude in each hydrobasin. Alpha diversity is rarefied to 10 stations per hydrobasin, using size level 5 hydrobasins for all panels. State of the Arctic Freshwater Biodiversity Report - Chapter 5 - Page 85 - Figure 5-2

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

Figure 4 -36 Freshwater fish sampling stations (A), ecoregion alpha diversity in each of the sampled ecoregions, as quantified by estimates of species richness from reference texts (Muus and Dahlstrøm 1971, Scott and Crossman 1973, Mecklenburg et al. 2002) and expert knowledge (academic and government scientists and traditional knowledge) (B), and ecoregion beta diversity (C) characterized according to components of beta diversity as either nestedness, turnover, no diversity (none, beta = 0), or similar nestedness and turnover (nestedness ~ turnover) in the circumpolar Arctic. Ecoregions are shown only where sampling stations occur. Fish sampling stations included in this study assessed complete fish assemblages at each location. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 74 - Figure 4-36