Vascular plant biodiversity of the lower Coppermine River valley and vicinity (Nunavut, Canada): an annotated checklist of an Arctic flora

Abstract

The Coppermine River in western Nunavut is one of Canada’s great Arctic rivers, yet its vascular plant flora is poorly known. Here, we report the results of a floristic inventory of the lower Coppermine River valley and vicinity, including Kugluk (Bloody Falls) Territorial Park and the hamlet of Kugluktuk. The study area is approximately 1,200 km2, extending from the forest-tundra south of the treeline to the Arctic coast. Vascular plant floristic data are based on a review of all previous collections from the area and more than 1,200 new collections made in 2014. Results are presented in an annotated checklist, including citation of all specimens examined, comments on taxonomy and distribution, and photographs for a subset of taxa. The vascular plant flora comprises 300 species (311 taxa), a 36.6% increase from the 190 species documented by previous collections made in the area over the last century, and is considerably more diverse than other local floras on mainland Nunavut. We document 207 taxa for Kugluk (Bloody Falls) Territorial Park, an important protected area for plants on mainland Nunavut. A total of 190 taxa are newly recorded for the study area. Of these, 14 taxa (13 species and one additional variety) are newly recorded for Nunavut (Allium schoenoprasum, Carex capitata, Draba lonchocarpa, Eremogone capillaris subsp. capillaris, Sabulina elegans, Eleocharis quinqueflora, Epilobium cf. anagallidifolium, Botrychium neolunaria, Botrychium tunux, Festuca altaica, Polygonum aviculare, Salix ovalifolia var. arctolitoralis, Salix ovalifolia var. ovalifolia and Stuckenia pectinata), seven species are newly recorded for mainland Nunavut (Carex gynocrates, Carex livida, Cryptogramma stelleri, Draba simmonsii, Festuca viviparoidea subsp. viviparoidea, Juncus alpinoarticulatus subsp. americanus and Salix pseudomyrsinites) and 56 range extensions are reported. The psbA-trnH and rbcL DNA sequence data were used to help identify the three Botrychium taxa recorded in the study area. Three new combinations are proposed: Petasites frigidus subsp. sagittatus (Banks ex Pursh) Saarela, Carex petricosa subsp. misandroides (Fernald) Saarela and Carex simpliciuscula subsp. subholarctica (T. V. Egorova) Saarela.

<p><strong>Vascular plant biodiversity of Dorset and Mallik islands, Nunavut, Canada: an annotated checklist of a middle Arctic flora in the Canadian Arctic Archipelago</strong></p>

“…As such, our empirical data support the established relationship between vascular plant diversity and summer temperature, as other studies have demonstrated (e.g., Bay 1997). The relationship was not as strong, however, in a recent analysis of the well-documented mainland Arctic flora of the lower Coppermine River valley and vicinity (Saarela et al 2017).…”

“…Overall, our results are consistent with other Arctic floristic studies that similarly demonstrated that total species diversity documented in an area increases with search effort through time, that different collectors at different times tend to document different subsets of total species diversity, and that in order to account for total vascular plant biodiversity in an area where there has been previous collecting, review of existing collections in multiple herbaria, the literature and newly collected material is necessary (Saarela et al 2013a, Saarela et al 2017, Saarela et al 2020.…”

“…Documented diversity in the park is intermediate between diversity documented in two other Nunavut Territorial parks. For example, 207 taxa are recorded from Kugluk (Bloody Falls) Territorial Park in western Nunavut (Saarela et al 2017), a small park that has been explored comprehensively. The rich diversity of vascular plants in Kugluk Territorial Park is variously attributed to its location in bioclimate Subzone D where plant diversity in local floras is greater than in other Arctic bioclimate subzones, its location along the Coppermine River valley where several primarily boreal-distributed species reach or are near their northern limits in Nunavut, some of which are not known to extend north beyond the boundaries of the park, and considerable habitat diversity within the park boundary.…”

Arctic shrub colonization lagged peak postglacial warmth: Molecular evidence in lake sediment from Arctic Canada

“…The QPT catchment is 14.5 km 2 with a modern vegetation cover of dwarf‐shrub tundra dominated by Betula glandulosa (here considered synonymous with B. nana spp. exilis after Saarela, Sokoloff, & Bull, ), Salix spp. (willow), other ericaceous shrubs, and sedges.…”

Improving distribution models of riparian vegetation with mobile laser scanning and hydraulic modelling

“…Moreover, they allow the extension of many boreal species into the (sub-) Arctic as outlier populations (e.g. [15,16]). Through the maintenance of a wide range of microhabitats, the river valleys may be one of the key environments for preservation of biodiversity when the climate changes ([14,17]).…”