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Satoru Kojima and Vladimir J. Krajina: Vegetation and environment of the coastal western hemlock zone in Strathcona Provincial Park, British Columbia, CanadaAbstract:A study of vegetation-environment relationships, based on the concept and approach of biogeoclimatology (Krajina, 1965, 1969, 1972), was conducted in Strathcona Provincial Park, British Columbia, where the vegetation showed some ecosystematic peculiarities resulting from a unique geological substratum, mainly basalt and limestone. As to the vegetation of the area, four orders, eight alliances, and eight associations (Braun-Bianquet, 1921, 1928, 1964; Krajina, 1933, 1972) with three variants were established and described. Twenty-two quantitatively measured environmental factors were statistically processed by means of analysis of variance, Duncan's new multiple-range test, and multiple regression analysis to detect significant differences among the five forested associations and to find the factor(s) most influential for the establishment and development of the associations. Soils of the area were especially high in base status, reflecting the strongly base-rich parent material. Thus, most of the soils examined were found to be Brunisols, which in reality are Pararendzinas (Kubiena, 1953). Despite the high amount of precipitation, Podzols were rather rare. In conclusion, it became apparent that the uniqueness and complexities of the vegetation lay in the considerable intermingling of species of very different ecological characteristics. Due to the base-rich edaphic conditions, some of the calciphiles occur commonly throughout the area, whereas a considerable number of acidophiles also grow on acid mor humus. This kind of double structure makes the vegetation more complex and more difficult to classify.M. Hoefs, I. McT. Cowan, and V.J. Krajina: Phytosociological analysis and synthesis of Sheep Mountain, southwest Yukon Territory, CanadaAbstract:This study presents an analysis of the vegetation on Sheep Mountain, adjacent to Kluane Lake, Kluane National Park, in southwest Yukon Territory. The study was conducted in the field by Manfred Hoefs as part of more extensive research on the ecology of the population of Dall sheep (Ovis dalli dalli), which uses the mountain as the basis of its year-round range. In particular, the south-facing slope of the mountain is essential sheep winter range.A vegetation map is presented outlining the distribution of 32 plant associations. These are described briefly and grouped into 23 alliances and 17 orders. They occur in the study area in three biogeoclimatic zones, which are discussed.The distribution of most of the plant associations was correlated with distinct environmental gradients with respect to snow depth and duration of snowcover, soil moisture during the growing season, aspect, slope, and some physical characteristics of the soils. Special attention has been given to the association of the sheep with the different plant associations. For those used extensively for grazing, vegetation yield figures are given. Vegetation yield figures of associations used as winter range by sheep and the zoological aspects of this study will be published elsewhere by Manfred Hoefs.