Circumpolar Arctic Vegetation Classification

Abstract

Aims: An Arctic Vegetation Classification (AVC) is needed to address issues related to rapid Arctic-wide changes to climate, land-use, and biodiversity. Location: The 7.1 million km 2 Arctic tundra biome. Approach and conclusions: The purpose, scope and conceptual framework for an Arctic Vegetation Archive (AVA) and Classification (AVC) were developed during numerous workshops starting in 1992. The AVA and AVC are modeled after the European vegetation archive (EVA) and classification (EVC). The AVA will use Turboveg for data management. The EVC will use a Braun-Blanquet (Br.-Bl.) classification approach. There are approximately 31,000 Arctic plots that could be included in the AVA. An Alaska AVA (AVA-AK, 24 datasets, 3026 plots) is a prototype for archives in other parts of the Arctic. The plan is to eventually merge data from other regions of the Arctic into a single Turboveg v3 database. We present the pros and cons of using the Br.-Bl. classification approach compared to the EcoVeg (US) and Biogeoclimatic Ecological Classification (Canada) approaches. The main advantages are that the Br.-Bl. approach already has been widely used in all regions of the Arctic, and many described, well-accepted vegetation classes have a pan-Arctic distribution. A crosswalk comparison of Dryas octopetala communities described according to the EcoVeg and the Braun-Blanquet approaches indicates that the non-parallel hierarchies of the two approaches make crosswalks difficult above the plantcommunity level. A preliminary Arctic prodromus contains a list of typical Arctic habitat types with associated described syntaxa from Europe, Greenland, western North America, and Alaska. Numerical clustering methods are used to provide an overview of the variability of habitat types across the range of datasets and to determine their relationship to previously described Braun-Blanquet syntaxa. We emphasize the need for continued maintenance of the Pan-Arctic Species List, and additional plot data to fully sample the variability across bioclimatic subzones, phytogeographic regions, and habitats in the Arctic. This will require standardized methods of plot-data collection, inclusion of physiogonomic information in the numeric analysis approaches to create formal definitions for vegetation units, and new methods of data sharing between the AVA and national vegetation-plot databases.

Vegetation and ecological characteristics of the northernmost salt marshes of the European continent

“…This habitat includes 'Coastal salt marshes habitats' which are determined by the presence of the vegetation of the alliance Puccinellion phryganodis. The second alliance, Caricion glareosae, which is well documented in the literature and prevails in our study area, is not mentioned by Walker et al (2017).…”

“…This vegetation is not known in the Arctic zone, the area of Eleochariteum uniglumis is confined to the Boreal zone. For instance, Sergienko (2013), within the whole Eurasian coasts of the Arctic Ocean recorded it only along the White Sea, which is not the part of the Arctic zone (Walker et al 2017). From the Barents Sea in northern Norway, Eleocharis uniglumis was noted by Nordhagen (1954) from the Munkelv estuary (south of our study area) in brackish marshes.…”

“…The most common criterion for its determination is the isotherm of the warmest month (July, 10°C) and/or the northern tree line. The latest work in which the Arctic line is determined according to a larger spectrum of natural conditions is that of Walker et al (2017). They divided the Arctic region to six subzones; the southernmost E zone is characterized by mean July temperatures of 10-12°C, vegetation is 2-3 layered, the moss layer is 5-10 cm thick, and the herbaceous/erect dwarf-shrub layer is 20-50 cm tall, sometimes with a low-shrub layer to 80 cm.…”

“…Our study objects are the coastal salt marshes of the Barents Sea of NE Norway which are situated in the northernmost part of the European continent. According to Walker et al (2017) this represents the southern border of the Arctic region ( Fig. 1).…”

Regional mapping of species‐level continuous foliar cover: beyond categorical vegetation mapping

“…These unrepresented regions lie within bioclimatic subzone C, which has a limited extent in extreme northernmost Alaska and is ecologically important (Walker et al. ). Although we limited sampling to the western half of arctic Alaska, our data covered the environmental variation across much of the Arctic Coastal Plain and Brooks Foothills.…”