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111	Quantitative characterization of field-estimated soil nutrient regimes in the coastal forest Klinka, Karel, Varga, Pal, Chourmouzis, Christine January 1999 (has links) One of the key factors in the site classification of the biogeoclimatic ecosystem classification is soil nutrient regime. Soil nutrient regime (SNR) represents the amount of essential soil nutrients available to plants over a period of several years. SNRs classes are assessed based on field identifiable (qualitative) criteria, not using quantitative measures. There have been several studies that attempted to quantitatively characterize regional soil nutrient gradients in the Coastal Western Hemlock (CWH) zone. In the study summarized here, the soils are influenced by a perhumid cool mesothermal climate. The objective of the study was to examine relationships between soil chemical properties and field-estimated SNRs. Carbon Classification Coastal Western hemlock zone Site index Site quality Soil nutrient regime Soil nutrients Nitrogen Western hemlock
112	Comparison of soil acidification and intensity of podzolization beneath decaying wood versus non-woody forest floors in coastal BC Klinka, Karel, Kayahara, Gordon J., Chourmouzis, Christine January 2001 (has links) 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. Coarse woody debris West coast hemlock Forest productivity Humus form Podzolization Site quality Soil nutrients Western hemlock
113	Demography and dendrochronology of a disjunct population of eastern hemlock in Southwestern Ohio Johnson, Marie 28 August 2018 (has links) No description available. Biology Botany Climate Change Conservation Demography Ecology Forestry eastern hemlock hemlock disjunct demography dendrochronology tree rings climate isolated population HWA hemlock woolly adelgid Clifton Gorge John Bryan Cantwell Cliffs management plan conservation edge population Yellow Springs tree core
114	Natural regeneration on clearcuts at the lower limit of the mountain hemlock zone Klinka, Karel January 1997 (has links) The Mountain Hemlock (MH) zone includes all subalpine forests along British Columbia’s coast. It occurs at elevations where most precipitation falls as snow and the growing season is less than 4 months long. The zone includes the continuous forest of the forested subzones and the tree islands of the parkland subzones (Figure 1). Old-growth stands are populated by mountain hemlock, Pacific silver fir, and Alaska yellow-cedar, and are among the least-disturbed ecosystems in the world. Canopy trees grow slowly and are commonly older than 600 years, while some Alaska yellow-cedars may be up to 2000 years old. Early regeneration failures followed slashburning and the planting of unsuitable species. Currently, the most successful and feasible option for reforesting cutovers is natural regeneration with a mix of the three main tree species, but uncertainties remain about the temporal and spatial pattern of regeneration, changes in species composition, and the time required for stand establishment after cutting. Our study addressed these concerns by examining regeneration patterns on 6 sites that were clearcut 11-12 years prior to sampling and left to regenerate naturally. The sites were located at the lower limits of the zone in the Tetrahedron Range, near Sechelt, at elevations from 1060-1100m. Alaska yellow-cedar Pacific silver fir Western hemlock Mountain hemlock Clearcuts Forest restoration Forest regeneration Stand structure Forest canopy gaps Blueberries bushes Snow cover
115	Pacific silver fir site index in relation to ecological measures of site quality Klinka, Karel January 1999 (has links) Ecosystem-specific forest management requires comprehension of tree species productivity in managed settings, and how this productivity varies with the ecological determinants of site quality, i.e., the environmental factors that directly affect the growth of plants: light, heat, soil moisture, soil nutrients, and soil aeration. A good understanding of this variation is necessary for making species- and site-specific silvicultural decisions to maximize productivity. Productivity of a given species is usually measured by site index (tree height at 50 years at breast height age). Quantitative relationships between site index and these measures of site quality provide predictive models for estimating site index. Pacific silver fir (Abies amabilis (Dougl. ex Loud.) Forbes) is an important timber crop species in the coastal forests of British Columbia. In relation to climate, its range in southwestern British Columbia extends from sea level to almost timberline, and from the hypermaritime region on western Vancouver Island to the subcontinental region on the leeward side of the Coast Mountains. In relation to soils, its range extends from slightly dry to wet sites and from very poor to very rich sites. In view of this relatively wide climatic amplitude, a large variability in productivity can be expected. It is particularly important to consider the growth performance of Pacific silver fir when decisions are made regarding whether or not to cut stands on high-elevation sites. In the study summarized here, relationships between Pacific silver fir site index and selected ecological measures of site quality were examined, and site index models using these measures as predictors were developed. West coast hemlock Engelmann spruce Subalpine fir Mountain hemlock Pacific silver fir Abies amabilis Forest site quality Site index Trees - Growth Forest productivity Forest ecology Soils
116	The association between western hemlock fine roots and woody versus non-woody forest floor substrates in coastal British Columbia Klinka, Karel January 2001 (has links) In the wetter climates associated with the coastal forests of the Pacific Northwest, coarse woody debris (CWD) accumulations in the form of snags, downed boles, and large branches can be large in natural forest ecosystems. Although maintaining organic matter for sustainable site productivity is not in dispute, the importance of CWD as a source of soil organic matter is questionable. Forest managers attempting to optimize timber production need to know how CWD affects short-term forest tree growth and productivity. This study addresses the question of the immediate value of CWD for growth of mature (90 year old) western hemlock (Hw). Because of practical difficulty with mature trees growing in different substrates, we utilized fine root distribution or proliferation, as an indicator of important substrates. Coarse woody debris West coast hemlock Western hemlock Forest floor Humification Humus forms Soil nutrients Site quality Root biomass Root density Root formation Substrates, Plant
117	Regeneration patterns in the Mountain hemlock zone Klinka, Karel, Brett, Bob, Chourmouzis, Christine January 1997 (has links) The Mountain Hemlock (MH) zone includes all subalpine forests along British Columbia’s coast. It occurs at elevations where most precipitation falls as snow and the growing season is less than 4 months long. The zone includes the continuous forest of the forested subzones and the tree islands of the parkland subzones (Figure 1). Old-growth stands are populated by mountain hemlock, Pacific silver fir, and Alaska yellow-cedar, and are among the least-disturbed ecosystems in the world. Canopy trees grow slowly and are commonly older than 600 years, while some Alaska yellow-cedars may be up to 2000 years old. Understanding regeneration patterns in the MH zone has become increasingly important as logging continues towards higher elevations of the zone where snowpacks are deeper. Alaska yellow-cedar Canopy trees Forest regeneration Gap dynamics Mountain hemlock Pacific silver fir Snow Stand structure Subalpine fir Subalpine forest Tree-island model Western hemlock
118	New height growth and site index models for Pacific silver fir in southwestern British Columbia Klinka, Karel, Splechtna, Bernhard E., Chourmouzis, Christine, Varga, Pal January 1999 (has links) Pacific silver fir (Abies amabilis (Dougl. ex Loud.) Forbes) is an important timber crop species in coastal forests of B.C. Its range extends from sea-level to almost timberline, and from the hypermaritime region on the west coast of Vancouver Island to the subcontinental region on the leeward side of the Coast Mountains. With this relatively wide climatic amplitude, a large variability in the height growth pattern of Pacific silver fir can be expected, since climate is considered to be the most influential determinant of the trajectory of height over age of forest trees. This variability, however, is not reflected in the height growth curves and site index tables used to estimate Pacific silver fir site index, since the curves and tables were developed from low-elevation stands on Vancouver Island. Consequently, when these curves and tables are applied to high-elevation or submaritime stands, we get biased estimates of site index. Accurate estimates of site index are necessary for accurate yield predictions. Furthermore, they are essential for making rational decisions about whether to cut the forest in situations where potential tree growth is marginal, such as in high-elevation forests. Climate Engelmann spruce - subalpine fir zone Forest productivity Height growth model Maritime Mountain hemlock Pacific silver fir Site index model Stem analysis Submaritime Tree growth Western hemlock
119	Investigation into the productivity of single- and mixed-species, second-growth stands of western hemlock and western redcedar Klinka, Karel, Collins, D. Bradley, Chourmouzis, Christine January 2001 (has links) In BC, it is required that harvested areas be regenerated with a mixture of tree species whenever appropriate to the site. This policy is based upon the assumption that increases in stand productivity, reliability, and/or biodiversity can be achieved in mixed-species stands. However, the knowledge justifying this policy is at best incomplete. Differences in forest productivity of mixed-species stands have been attributed mostly to competition. However, an increasing number of studies are providing evidence to support alternate theories, in which positive plant interactions play a major role. Positive plant interactions are divided into two components: (i) competitive reduction through structural and physiological differences in above and below ground structures, and (ii) facilitation through any positive effect on the growing environment of one plant species by another. These theories have yet to be tested in forest ecosystems. The objectives of this study, with respect to naturally established, unmanaged, second-growth stands of western hemlock (Hw) (Tsuga heterophylla (Raf.) Sarg.), western redcedar (Cw) (Thuja plicata Donn ex D. Don in Lamb.), and their mixtures, were: (1) to review the mechanisms of positive plant interactions and their potential to occur in these mixtures, and (2) to compare the productivity of these three stand types, using relative and absolute yield. West coast hemlock Forest productivity Mixed-species stands Single-species stands Volume Western hemlock Western redcedar Forest biodiversity Forest biomass Forest regeneration
120	American Chestnut Restoration in Eastern Hemlock-Dominated Forests of Southeast Ohio Daniel, Nathan A. 25 July 2012 (has links) No description available. Ecology Environmental Science Environmental Studies American chestnut Castanea dentata Eastern hemlock Tsuga canadensis restoration ecology hemlock wooly adelgid Adelges tsugae chestnut blight Cryphonectria parasitica Hocking Hills

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