The riparian vegetation in arctic Alaska mainly consists of willow shrub communities that are functionally important components of arctic landscape ecosystems. Willow communities along a south-north transect from the Brooks Range to Prudhoe Bay were described by Schickhoff et al. (2002). Support for the project was provided by the Max Kade Foundation grant KADE-OCG 3088 to U. Schickhoff, by the U. S. National Science Foundation grant OPP-9400083 to M. D. Walker, and by the U. S. National Science Foundation grant 9908829 to D. A. Walker. Plots are primarily in the watersheds of Sagavanirktok River and Kuparuk River accessible from the Dalton Highway.
Eighty-five relevés were subjectively located in three broad habitat types including: 1) tall willow shrub communities on floodplains, gravel bars and lower terraces as well as on upland montane stream banks (27 plots) (Epilobio-Salicetum alaxensis association, including two subassociations parnassietosum kotzebuei and polemonietosum acutiflori), 2) more or less open low willow shrub communities on the banks of upland tundra streams as well as upper terraces from about 950 m in elevation down to the coastal plain (35 plots) (Anemono-Salicetum richardsonii association, including two subassociations, lupinetosum arctici and salicetosum pulchrae), and 3) low willow shrub communities restricted to the most humid and acid banks of upland tundra streams in the Arctic foothills roughly between 400 and 800 m in elevation (23 plots) (Valeriano-Salicetum pulchrae with several variants).
Plots were not permanently marked. Relevé sizes were assessed according to the minimal area approach and varied between 60 square meters (low shrublands) and 100 square meters (tall shrublands). Species and environmental data (including soil physical variables and subjective site assessments) were collected in the field and soil samples were brought back to the lab for chemical analysis. Vegetation was classified according to the Braun-Blanquet approach, which resulted in the description of three associations and four subassociations published in Schickhoff et al. (2002). DCA ordinations were used to analyze vegetation-environment relationships.
Schickhoff, U., M. D. Walker and D. A. Walker. 2002. Riparian willow communities on the Arctic Slope of Alaska and their environmental relationships: A classification and ordination analysis. Phytocoenologia 32:145-204.