Representative diatom profiles from the circumpolar Arctic showing the character and timing of recent assemblage shifts.

Arctic Biodiversity Assessment (ABA) 2013.

Figure 13.5. Representative diatom profiles from the circumpolar Arctic showing the character and timing of recent assemblage shifts. Site locations (A-H) are shown on the map. Chronologies are based primarily on constant rate of supply modeling of excess sediment 210Pb activities. Beta-diversity values (in SD units) are shown in bold next to each site’s name. Colored intervals demarcate major assemblage changes and are coded: blue = 0-1.0 SD, green = 1.0- 1.24 SD, orange = 1.24-1.5 SD, red = > 1.5 SD. All data are expressed as relative frequency percentages of individual or collated diatom taxa based on counts of > 400 valves per sample. Siliceous algal remains, specifi cally the valves of diatoms (Bacillariophyceae) and the stomatocysts and scales of chrysophytes (golden brown algae Chrysophyceae and Synurophyceae), as well as chitinous invertebrate remains (Chironomidae, Diptera and Cladocera, Crustacea), are the primary paleoindicators in lake sediments that provide reliable records of changes in water quality, habitat and catchment processes.

From Smol et al. (2005).

Conservation of Arctic Flora and Fauna (CAFF)

www.caff.is 

The data can be downloaded freely.

Users are requested to reference it source.

Meltofte, H. (ed.) 2013. Arctic Biodiversity Assessment. Status and trends in Arctic biodiversity. Conservation of Arctic Flora and Fauna, Akureyri.