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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Using economic factors in managing Appalachian hardwoods for high quality

Cayen, Timothy J. January 1987 (has links)
Because of the extremely wide range in product values from hardwood stands, harvest decisions must consider a multiplicity of factors, many of them economic. Among these are species, tree size, tree quality, logging costs, and market alternatives. This study demonstrates how to incorporate these, using a new microcomputer program with growth projection, YIELD-MS (Hepp, 1986), to find an economically favorable regime for a particular hardwood stand. The simulation approach presented allows for economic and silvicultural comparisons of many alternative treatments that need to be considered each time a stand is re-examined for prescription in the progress of a management plan. A decision tree was developed as a systematic way of reviewing the possibilities. In order to reduce the search time necessary to move through the decision tree, some parameters were found for describing value growth of hardwood stands. The percentage of stand basal area capable of grade change (PBAGI) and the spread of percent price differentials between log grades (PPD) were tested by a series of simulation runs on data from a variety of actual stand conditions found in the Appalachian region. The results of these simulation and sensitivity tests indicate that as PBAGI and PPD increased the various economic criteria improved in value. It is concluded that recent developments in growth and yield modeling make it possible to economically evaluate various silvicultural treatments and harvest intensities at the stand level, and indications are that management for high quality can be economically desirable. / M.S.
82

The influence of perceived employment opportunities on educational performance in Appalachia

Broomhall, David E. 06 August 2007 (has links)
The purpose of this study is to analyze the process of education in central Appalachia. Persistent economic and social problems in the region such as unemployment, low average incomes, low educational attainment, and widespread poverty have defied solution. This study uses primary data from high school-aged youths and their parents' in four rural school districts in Appalachia to examine incentive structures which encourage, or discourage, individuals from obtaining education. The study evaluates a number of influences on the value that individuals place on education including community and employer influences, the willingness of youths to relocate to obtain employment, and the perception of employment opportunities in the local community. The study also examines inter-generational aspects of educational behavior by analyzing the influence of socioeconomic background, and parental attitudes and values, on the attitudes and values of their children. The findings indicate that socioeconomic background, and parental and community influences have a significant impact on educational behavior in Appalachia. / Ph. D.
83

Habitat use by nongame birds in central Appalachian riparian forests

Murray, Norman L. 16 February 2010 (has links)
I sampled bird densities and habitat characteristics along a gradient from a second-order stream to 454 m upland at 16 locations. Total bird density, species richness, and densities of 28 bird species were tested to determine whether riparian habitats influenced bird communities. Total bird density and species richness showed no riparian influence. Acadian flycatchers and Louisiana waterthrushes were closely linked to the streams. Carolina wrens, American robins, and red-eyed vireos showed weaker but positive associations with the streams. Eastern wood-pewees, black-and-white warblers, pine warblers, worm-eating warblers, and scarlet tanagers demonstrated a negative association with streams. A cluster analysis was used to group the 28 bird species into 5 assemblages based on their distribution among the sampling stations. The species were classified as belonging to the following assemblages: riparian, upland forest, mesic hardwoods, xeric forest, and mature hardwoods generalist. Logistic models were developed to predict the number of species in each assemblage that were present and the presence of each species at each station based on the habitat characteristics at the site. Regression models were developed to predict the relative abundance of each assemblage and species at occupied stations. / Master of Science
84

Labor Market Dynamics in West Virginia and the Appalachian Region

Beverly, Joshua Paul 11 January 2023 (has links)
This dissertation consists of three manuscripts analyzing labor market dynamics in West Virginia and the Appalachian Region. The first manuscript examines the dynamic effects of national, regional, and local labor market shocks on labor force participation rates in Appalachia. A dynamic factor model with time-varying loading parameters and stochastic volatility is used to explore the synchronicity and divergence between state labor force participation rates within and outside the Appalachian region. We find that the choice of time and state is crucial to the relative importance of the level of synchronization on observed change in LFPR variations. Our findings can help better target labor policy by taking advantage of the sensitivity exhibited by each state to various labor market conditions. The second manuscript examines the dynamic effects of state, Metro/Non-Metro, and county labor market shocks on labor force participation rates in West Virginia. In the first stage, using a dynamic factor model, we find that non-metropolitan and county-specific components are dominant contributors to the observed variations in the change in West Virginia LFPRs. In the second stage, using a fixed effects panel model, we find county demographics, education levels, income, access to interstate highways, and industry composition are useful covariates for explaining the variance contributions of the state, metro/non-metro and county factors. The third manuscript uses cointegration analysis in the presence of structural breaks to determine whether the Unemployment Invariance Hypothesis exists in West Virginia. Using monthly labor force data from 1976 - 2022, we find mixed support for the unemployment invariance, added worker effect, and discouraged worker effect hypotheses over multiple sub-sample periods. These results suggest that labor markets are temporally-dynamic, and a one-size-fits-all approach could prove disadvantageous to growth. / Doctor of Philosophy / This dissertation focuses on labor market dynamics in West Virginia and the Appalachian Region. In the first of three manuscripts, we investigate how much U.S. state labor force participation rates move together nationally, and within the Appalachian Region. We find that how much labor force participation rates move together across the U.S. and within the Appalachian Region depends on the choice of time and state. In the second manuscript, we examine how much West Virginia county labor force participation rates move together across the state and within the Metropolitan and Non-Metropolitan regions. We also study how county characteristics such as industry composition and education levels influence the variation in how much labor force participation rates move together. We find that Non-metropolitan county labor force participation rates exhibit similar dynamic behavior and that education, personal income, access to highways, and industry composition of the counties influences how much the rates move together at the different levels. In the third manuscript, we investigate whether changes in the unemployment rate in West Virginia result influences that state's labor force participation rate in the long-run. We find that evidence of said long-run relationship albeit changing over time. We posit that the relationship dynamics are largely explained by the ensuing labor market and economic conditions. By extension, labor market policies and interventions should be timely and flexible.
85

Ice storms as a disturbance factor in Appalachian oak forests

Whitney, Helen E. January 1982 (has links)
Ice (glaze) storms are frequent natural disturbances in eastern deciduous forests. Two opposing hypotheses exist in the literature regarding the effect of glaze on forest succession. In the first view, succession is said to be accelerated as pioneer species sustain greater damage than equilibrium species. The resistant equilibrium species would then fill canopy gaps, shifting the stand to a more advanced stage. Alternatively, extensive canopy damage allows more light to reach the forest floor perhaps favoring the germination and establishment of pioneer seedlings. Survival of these individuals would return the community to an earlier successional stage, or maintain pioneer communities. This study examined the response of the reproduction and susceptibility of tree species (by damage and mortality) two growing seasons after an ice storm, across a moisture and successional gradient. Four stands were studied: <i>Liriodendron</i>, mesic and xeric <i>Pinus</i>, and <i>Quercus</i>. Damage for most species was consistent across stands, with larger trees generally sustaining greater damage than smaller trees or saplings. Mortality increased with increasing stem size and severity of damage for most species. However, while damage to <i>Liriodendron tulipifera</i> was very high, actual mortality was low due to its ability to sprout. Also, because seedling reproduction of pioneer species was stimulated in this stand, succession appeared to be retarded. Succession was accelerated in the mesic <i>Pinus</i> stand where mortality of canopy trees was high and where removal of the canopy stimulated growth and sprouting of understory equilibrium species. Succession of the stands on drier sites (e.g. <i>Quercus</i> and xeric <i>Pinus</i>) appeared unaffected as the composition of tree seedlings remained essentially unchanged after disturbance. Thus, the response of a community to ice damage depends on the interrelated variables of vegetation composition, successional status, and topographic position. / M. S.
86

U-Pb dating of granites from the Charlotte belt of the southern Appalachians

Hund, Erik A. 15 November 2013 (has links)
New U-Pb zircon ages from plutons in the Charlotte belt of the southern Appalachians have provided evidence of Cambro-Ordovician and Siluro-Devonian magmatic activity. Several U-Pb zircon ages of Cambro-Ordovician plutons predate their Rb-Sr whole rock ages by as much as 60 m.y., suggesting a post emplacement disturbance of the Rb-Sr isotopic systems. Comparison of geologic setting, chemistry, and temporal and spatial distribution of Charlotte belt Siluro-Devonian plutons with those of other tectonic environments, specifically plutons from tensional environments, suggests a model for strike-slip accretion. / Master of Science
87

Marginality in Appalachian professional women

Woods, Elizabeth Ruggles January 1986 (has links)
This research examined a sample of first generation professional women from the Appalachian region with the goal of description and exploration of issues related to their professional lives. Data from 20 intensive interviews were organized around an expanded version of Park's (1928) concept of marginality which yielded three major foci: (1) self definitions of marginality; (2) consequences of marginality; and (3) adaptive strategies of the marginal person. A continuum conceptualization of marginality emerged from the data with four categories of self-definition: (1) essential marginality; (2) situational marginality; (3) occasional marginality; and (4) non-marginality. Three major types of consequences, social, professional, and personal were experienced; and adaptive strategies of the active intentional, reactive intentional and non-intentional types were employed by the subjects. The data suggested possible relationships between type of job held-- especially whether in a male dominated field--and types as well as degree of marginality experienced. Also, degree of marginality appears to have some relationship to consequences experienced and, in turn, to adaptive strategies employed by subjects. This research contributes to the literature by expanding the existing concept of marginality into a continuum and using this new conceptualization as a framework for the analysis of first generation professional women from the Appalachian region. / M.S.
88

Gravity profile evaluation of geological cross-sections through the Southern Appalachians in Frederick County, Virginia

Mason, Michael Randolph 06 February 2013 (has links)
The geology of Frederick County, Virginia is known mostly from surface mapping. Based on this work are interpretations of the subsurface geology including cross sections which have been constrained by the surface geology and by the method of area balancing based upon palinspastic reconstruction. With the intent to further constrain these cross sections. gravity measurements were made at 422 sites in Frederick County. Then, gravity anomalies were compared with theoretical gravity profiles calculated from two dimensional models of density distribution based upon the cross sections. Using the cross section geometry and densities published for the known and inferred rock units, the theoretical gravity profiles did not compare favorably with corresponding Bouguer gravity profiles. However, by modifying the geometry of the model units and adjusting the model unit densities, a reasonable fit between theoretical and Bouguer gravity profiles was obtained. Although the geometrical modifications adhered to the structural style, no attempt was made to area balance these modifications within the model. / Master of Science
89

Taxonomy, genesis, and parent material distribution of high- elevation forest soils in the southern Appalachians

Feldman, Steven B. January 1989 (has links)
High-elevation spruce-fir forests in the southern Appalachians may potentially be in a state of decline as a result of either natural or anthropogenic causes. Soils were investigated in areas representative of 117 permanent intensive field plots established to evaluate changes in forest composition that may be influenced by the deposition of atmospheric pollutants. A total of 35 pedons were described, sampled, and characterized. Over 75% of the soils studied were classified in the field as either Typic or Pachic Haplumbrepts, but weakly developed spodic horizons were identified in 13 of the soils by chemical determinations in the laboratory. A high degree of morphological similarity exists between soils in these areas despite widespread differences in parent material and local geology. This similarity is the result of physical mixing of these soils by climatically-driven slope processes. A considerable amount of chemical variability exists in these soils which is not expressed in morphological characteristics. Multiple discriminant analysis established that physical and morphological properties used to separate and classify these soils in the field were not significantly different between study areas. Parent material differences, however, expressed in both soil chemical and mineralogical properties, were sufficiently different between study areas to result in the clear separation of soils into distinct groups. The importance of nutrient cycling in these spruce-fir forests is underscored by high levels of exchangeable bases in surface horizons relative to lower in the profile. This suggests that disturbances to the forest floor resulting from fire, overgrazing, logging, or erosion could have a major impact on ecosystem resilience during stress. / Master of Science
90

Ecological and taxonomic studies of the Russulaceae and other ectomycorrhizal Basidiomycetes in the high-elevation forests of the southern Appalachians

Bills, Gerald F. January 1985 (has links)
Temperate and boreal fungal floras indicate that species of the Russulaceae (the genera <i>Russula</i> and<i>Lactarius</i>) are among the dominant ectomycorrhizal fungi in forest communities. The contribution of the Russulaceae to the communities of ectomycorrhizal Basidiomycetes fruiting in red spruce and adjacent northern hardwood forests in West Virginia was evaluated and compared with other ectomycorrhizal Basidiomycetes occupying the same habitats. The Russulaceae exhibited the greatest species diversity of any family of ectomycorrhizal fungi fruiting in the stands studied (44% of the species in spruce, 39% of the species in hardwoods). Species of <i>Lactarius</i> and <i>Russula</i> were among the most productive in both forests. Species diversity, productivity, and fruiting phenology of all ectomycorrhizal Basidiomycetes were compared between red spruce and northern hardwood stands for a 3-year period. Sporocarp numbers and sporocarp frequency in 384 four m² quadrats in each forest type was used to estimate productivity. Species richness was greater in hardwoods (36 species) than in spruce (27 species). Nine species were common to both forests. Most productivity was concentrated in a few species, while most species were rare. Species-area curves were constructed for both forests. Fungal species and tree species composition in both forests were compared by principal component analysis. Fungi in spruce forests were more productive than in hardwood forests. Productivity was highly variable among the three seasons studied because of climatic variability. Sporocarp abundance and frequency were positively correlated with basal area and density of mycorrhizal trees and were negatively correlated with fern cover in hardwood forests. Fruiting seasons extended from early July to late September or early October. Numbers of species fruiting from the same four m² quadrats ranged from 0 to 7 in spruce forests and 0 to 5 in hardwood forests. Spatial patterns of sporocarps of major species were characterized by the variance-to-mean ratio, mean crowding, patchiness, and spatial autocorrelation and were found to exhibit highly aggregated, contagious patterns. Interspecific associations between pairs of major species were measured by 2 x 2 contingency tables and Cole's index of association. A taxonomie and geographic survey of <i>Russula</i> and <i>Lactarius</i> in both the quantitative study areas and in similar habitats in the Southern Appalachians was presented. / Ph. D.

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