Thesis (M.S.)--Oregon State University, 2000. / Typescript (photocopy). Includes bibliographical references (leaves 76-84). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2000. / Typescript (photocopy). Includes bibliographical references (leaves 80-82). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 1995. / Typescript (photocopy). Includes bibliographical references (leaves 53-54). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 55-60). Also available on the World Wide Web.

Thesis (M.S.P.D.) - University of Queensland, 2004. / Includes bibliography.

Droughts are a common disturbance experienced by forest systems across the southeastern United States and are expected to increase in frequency in the near future. Few empirical studies have evaluated the response of individual tree resistance and resilience following silvicultural treatment in longleaf pine (Pinus palustris Mill.). This study evaluates the differences in drought responses between two forests during three different periods. The first period evaluated pretreatment (2000) conditions, while the second (2006), and third (2011) compared conditions after the implementation of five silvicultural treatments. The main findings are that, as additional basal area is removed, both individual tree resistance and resilience to drought increase. Moreover, as drought intensity decreases, both resistance and resilience metrics increase. Finally, higher competitive status of individual trees warranted higher resistance to drought compared to trees of a lower competitive status.

Knowledge of old-growth Juniperus occidentalis woodlands, which occur in central and eastern Oregon, is limited. Wise management of these woodlands necessitates a better understanding of the community ecology. The community structure of woodlands at seven sites in three areas of central Oregon was studied. Measurements taken at nine plots per site included tree density, canopy cover, heights, diameters, and canopy areas; cover of each understory species and other ground covers; density of shrubs by species and condition; density of woody debris as downed pieces and standing dead trees; and topographic and soil parameters. Tree cores were taken for aging, although heartwood rot is pervasive in older trees. Factors of interest included cover and richness in all vegetative layers, variability within and between sites, and comparison of J. occidentalis woodlands to other old-growth communities. J. occidentalis woodlands were found to have a minimum of 80 trees over 200 years old per hectare, canopy cover of 10-35%, and understory cover of less than 20%. Woody detritus was primarily retained aloft and decomposed by weathering. Tree morphology was highly variable, but decadence was common. Outward physical attributes did not appear to be reliable predictors of tree age. Shrub cover was strongly correlated (r��=0.66) with the combination of elevation, ground cover by rock, and clay content of the soil. Perennial grass cover increased with elevation and the sand-sized soil fraction (r��=0.46). Understory cover, dominated by perennial grass, showed a weaker correlation with the same parameters (r��=0.20). Other significant findings included correlation of juniper cover with elevation, sand. and heat load (r��=0.38). Tree cover was found to increase by almost 1% for each 1% increase in sand content of the soil and by almost 8% for each 100m increase in elevation, while heat load, based on aspect. had a smaller effect. Plots grouped strongly by area. suggesting that there is a stronger influence of area than site on community composition for most of the sites and that differences between areas overwhelm the differences within areas. / Graduation date: 1999

The objective of the study is to compare the bird communities between natural forests and Taiwania (Taiwania cryptomerioides) plantations. I surveyed the bird communities in the experimental forests of Liu-Kuei Station, Taiwan Forestry Research Institute in Kaohsiung County, Taiwan during the breeding season from late March to early July in 2001 and 2002. A total of 34 bird species were recorded during the 2-year study period. Of these, thirty-one species were recorded in natural forests and 25 species in Taiwania plantations. Four indices, including diversity, evenness, species richness and total densities, could not clearly explain the differences between two forest types. Of the 11 assemblage guilds, carnivores and canopy woodpeckers only occurred in natural forests. The limited availability of nest holes limits the densities of species required holes to nest. Due to complex forest structures and stable and plentiful food resource, canopy foliage omnivores have stable densities in natural forests. But the very dense understory vegetation limits the number of suitable nesting or foraging sites require by ground insectivores. Because of less vegetation food resource, canopy foliage insectivores are the main component of the bird communities in Taiwania plantations. In addition, the foliage structure of the conifers is adequate for canopy hover insectivores to forage. The result of detrended correspondence analysis revealed that the differences of the bird communities between natural forests and Taiwania plantations mainly due to the complexity of the forest structures, nevertheless, the altitude and spatial variation would produce some impacts.

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 422-459).

Thesis (M.S.)--Oregon State University, 2001. / Typescript (photocopy). Includes bibliographical references (leaves 53-57). Also available on the World Wide Web.