Some Aspects of Plant Water Relations in Alaskan Arctic Tundra Species

Abstract
Xylem pressure potentials and interrelations between relative water content, xylem pressure potential and leaf conductance of 24 spp. which are common in tussock and montane tundra were compared at 4 sites in Alaska [USA] in 1977 and 1978. Evergreen shrubs had the lowest leaf conductances, graminoids and forbs the highest. The relations between relative water content, xylem pressure potential and leaf conductance were not unique to a growth form nor to a vegetation zone. Although different species attained different minimum pressure potentials, individuals of a species showed similar potentials in a variety of sites.