Christine Chourmouzis

The distribution and synopsis of ecological and silvical characteristics of tree species of British Columbia's forests

DISTRIBUTION AND SYNOPSIS OF ECOLOGICAL Pseudotsuga menziesii AND SILVICAL CHARACTERISTICS Taxus brevifolia ACKNOWLEDGMENTS Softwoods Thuja plicata INTRODUCTION Abies amabilis Tsuga heterophylla Tsuga mertensiana EXPLANATORY NOTES Abies grandis Hardwoods Nomenclature Abies lasiocarpa Acer macrophyllum Geographic Range Chamaecyparis nootkatensis Alnus rubra Climatic Amplitudes Juniperus scopulorum Alnus tenuifolia Orographic Amplitude Larix laricina Arbutus menziesii Edaphic Amplitudes Larix lyallii Betula neoalaskana Soil Moisture Regime Larix occidentalis Betula papyrifera Soil Nutrient Regime Picea engelmannii Cornus nuttallii Root System Characteristics Picea glauca Populus balsamifera Tolerances Picea mariana Populus tremuloides Damaging Agents Picea sitchensis Populus trichocarpa Associated Species and Successional Role Pinus albicaulis Prunus emarginata Silvical Characteristics Pinus banksiana Quercus garryana Special Adaptations and Indicator Values Pinus contorta Rhamnus purshiana Genetics Pinus flexilis SPECIES DIVERSITY Notes Pinus monticola SPECIES COMPARISONS CD-ROM Pinus ponderosa LITERATURE CITED

Phytogeographical and community similarities of alpine tundras of Changbaishan Summit, China, and Indian Peaks, USA

We compared the diversity, phytogeography, and plant communities in two mid-latitude alpine tundras with comparable aerial and elevational extents: Changbaishan Sum- mit in eastern Asia and Indian Peaks in western North America. Despite wide separation, the two areas shared 72 species. In all, 43 % of the species on Changbaishan Summit are also distributed in the alpine zones of western North America, while 22 % of the species on Indian Peaks are also distributed in the alpine zones of eastern Asia. Almost all the shared species also occur in the Beringian region. Phytogeographical profiles of species and genera showed that 69 % of species and over 90 % of genera in both alpine tundras belong to the three phytogeographical categories: cosmopolitan, circumpolar, and Asian-North American. We attributed the current floristic relationship between these widely separated areas to the peri- odic past land connection between the two continents during the Tertiary and Pleistocene. Indian Peaks has a closer floristic relationship with the Arctic tundra than does Changbaishan Summit. Indian Peaks also has 45 % higher species richness and lower vegetation cover than Changbaishan Summit. Plant communities from the two areas were completely separated in the two-way indicator species analysis and non- metric multidimensional scaling on floristic data at both species and generic levels, whereas ordination of communities by soil data produced a greater overlap. The plant communities on Changbaishan Summit in general have lower alpha diversity, higher beta diversity (lower between-community floristic simi- larity), and more rare species than does Indian Peaks. Mosaic diversity does not differ in the two alpine tundras, although the analysis suggests that Changbaishan Summit communities are more widely spaced on gradients than the Indian Peaks com- munities.

Phytogeography of Northeast Asia

Northeast Asia as defined in this study includes the Russian Far East, Northeast China, the northern part of the Korean Peninsula, and Hokkaido Island (Japan). We determined the species richness of Northeast Asia at various spatial scales, analyzed the floristic relationships among geographic regions within Northeast Asia, and compared the flora of Northeast Asia with surrounding floras. The flora of Northeast Asia consists of 971 genera and 4953 species of native vascular plants. Based on their worldwide distributions, the 971 genera were grouped into fourteen phytogeographic elements. Over 900 species of vascular plants are endemic to Northeast Asia. Northeast Asia shares 39% of its species with eastern Siberia-Mongolia, 24% with Europe, 16.2% with western North America, and 12.4% with eastern North America. Species richness and floristic relationships among different regions within Northeast Asia were discussed. The northernmost (Arctic) region shares 64% of its genera and 9% of its species with the southernmost (warm temperate) region. The geographic setting, climate, vegetation, and endemism of each of the eighteen regions of Northeast Asia were described and characterized. The geographic distributions of the 53 most important tree species in Northeast Asia were mapped.

Classification and ecology of the mid-seral Picea mariana forests of British Columbia

Abstract We sampled vegetation and soils of, and classified mid-seral, even-aged, fire-origin, upland Picea mariana ecosystems in the Boreal White & Black Spruce and Sub-boreal Spruce zones of British Columbia, Canada. We applied multivariate and tabular methods to analyse and synthesize the data from 121 plots according to the methods of biogeoclimatic ecosystem classification. We delineated seven basic vegetation units and described their vegetation and environmental features. However, the delineated units could not be related to neither of the taxonomies proposed for the North American boreal forest communities. Although species-poor, the understorey vegetation in the sampled ecosystems provided for a sufficient floristic differentiation, which matched well the major edaphic differences between the units. The classification of mid-seral boreal ecosystems may be more useful that based on old-growth stands that are infrequent or lacking in the landscape due to wildfires. Abbreviations: BC = British Columbia; NMDS = Non-metric multidimensional scaling; SMR = Soil moisture regime; SNR = Soil nutrient regime. Nomenclature: Qian & Klinka (1998).

Comparison of soil acidification and intensity of podzolization beneath decaying wood versus non-woody forest floors in coastal BC

Forest managers concerned with maintaining soil productivity must consider the impacts of forestry practices upon the features of a site. One critical feature is the amount and type of organic matter on a site, which may affect soil development. This study addresses the question of whether CWD accumulations increase the intensity of podzolization, thus reducing the long-term productivity of a site.

Relationships between site index of major tree species in the ESSF zone and ecological measures of site quality

Knowledge of ecological characteristics of sites and growth of trees on different sites is fundamental for silvicultural decision-making and planning. With the biogeoclimatic ecosystem classification in place in British Columbia, silvicultural management has been given an ecological foundation; however, relationships between growth and site quality have not yet been fully investigated, particularly for high-elevation tree species and sites. One of the contributing factors for this situation is limited knowledge of forest productivity in the high-elevation Mountain Hemlock (MH) and Engelmann Spruce Subalpine Fir (ESSF) biogeoclimatic zones. Consequently, the management and planning in the high-elevation forest is fraught with difficulties and uncertainties. Current harvest rates of old-growth forest stands and the method and distribution of cuttings in these zones suggest that there needs to be more recognition of the uppermost elevation limit for harvesting.

Forest floor nutrient properties in single- and mixed-species stands of Western hemlock and Western redcedar

The influence of tree species on forest soils has been the subject of study for at least a century. Of particular interest have been western hemlock (Tsuga heterophylla (Raf.) Sarg.) and western redcedar (Thuja plicata Donn ex D. Don) two of the most common tree species in coastal and southern British Columbia, but each with a different nutrient amplitude. It has generally been found that acid, mycogeneous Mor humus forms develop in hemlock stands, while less acid and more zoogenous Mormoder, Moder, or even Mull humus forms develop in redcedar stands.

Species diversity and floristic relationships of the understory vegetation in black spruce and trembling aspen stands in the boreal forest of British Columbia

The boreal forest is confined to the Northern Hemisphere and is the most continuous and extensive forest in the world. In North America boreal forest extends from the Pacific to Atlantic coast spanning over 10° latitude. White spruce (Picea glauca (Moench) Voss), black spruce (P. mariana (Mill.) B.S.P.), and trembling aspen (Populus tremuloides Michx.) are among the dominant tree species. Black spruce and trembling aspen may form pure stands and occupy similar sites as their edaphic amplitudes overlap; however, spruce is rare on water-deficient sites and aspen does not tolerate excess water.

The structure of single- and mixed-species, second-growth stands of Western hemlock and Western redcedar

Research on growth and stand structure has shown that the spatial distribution of trees is one of the key determinants of stand productivity. Forest inventories and ecological surveys carried out in British Columbia (BC) have shown that the structure of naturally established, unmanaged stands varies from simple (single-species, single-storied, and even-aged) to complex (multi-species, multi-storied, and uneven-aged). Only a few studies have quantitatively characterized this range of structural complexity, with nearly all studies focusing on old-growth stands.

Classification of high-elevation, non-forested plant communities in coastal British Columbia. Full report.

Non-forested plant communities occur where trees are permanently absent, or where they can survive only as prostrate or stunted shrubs. Within our region, nonforested communities generally dominate sites that are snow-free for <4 months. We aimed to develop a classification that organizes communities into groups in a way which shows the greatest number of relationships, is easily retained in memory, and is easily conveyed through instructions.