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Modeling the Distribution of the Northern Hardwood Forest Type in Carolina Northern Flying Squirrel (Glaucomys sabrinus coloratus) Recovery Areas of the Southern AppalachiansEvans, Andrew M. 25 June 2013 (has links)
The northern hardwood forest type is a critical habitat component for the endangered Carolina northern flying squirrel (CNFS; Glaucomys sabrinus coloratus) for denning sites and corridor habitats between montane conifer patches where the squirrel forages. This study examined terrain data, and patterns of occurrence for the northern hardwood forest type in the recovery areas of CNFS in western North Carolina and southwestern Virginia with the purpose of creating a more robust predictive model of this forest type for spatial delineation. I recorded overstory species composition as well as terrain variables at 338 points throughout the study area in order to quantitatively define the northern hardwood forest type. These data were used in conjunction with digital terrain data for creation of the predictive model. Terrain variables we examined to attempt to differentiate northern hardwoods from other forest types included elevation, aspect, slope gradient, curvature, and landform index. I used an information-theoretic approach to assess six models based on existing literature and a global model. My results indicate that on a regional, multi-state scale, latitude, elevation, aspect, and landform index (LFI) of an area are significant predictors of the presence of the northern hardwood forest type in the southern Appalachians. My model consisting of Elevation + LFI was the best approximating model based on lowest AICc score. Our Elevation + LFI model correctly predicted northern hardwood presence at 78.2% of our sample points observed to be northern hardwoods. I then used this model to create a predictive map of the distribution of the northern hardwood forest type in CNFS recovery areas. / Master of Science
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Phylogeographic Analyses of Obligate and Facultative Cave Crayfish Species on the Cumberland Plateau of the Southern AppalachiansBuhay, Jennifer Elizabeth 12 July 2006 (has links) (PDF)
Cave systems and their unique biota are widely viewed as highly endangered, yet very little is known about basic life history, ecology, distributions, habitat requirements, and evolutionary relationships of subterranean species. The crux of the problem in cave studies is the assumption that traditionally defined morpho-species represent distinct evolutionary lineages. Convergence is exhibited in the morphologies of many animal groups, vertebrate and invertebrate, which leads to confusion in diagnosing species' boundaries, geographic distributions, gene flow routes, and imperilment. This dissertation research includes phylogeographic analyses of freshwater cave-dwelling crayfishes in the Southern Appalachians, a global hotspot of subterranean biodiversity. By examining population structure in light of habitat, geology, geography, and hydrology, we can better provide conservation direction for these groundwater species. Chapter one introduces a method, Nested Clade Phylogeographic Analysis (NCPA), used to investigate hypotheses about historical and current population structures within species. Using a statistically-testable framework, NCPA can elucidate historical speciation patterns and current routes of gene flow using genetic sequence data of thoroughly-sampled species. Using diverse examples, the chapter details the methodology of building haplotype networks, performing the geographic analyses, inferring past and contemporary evolutionary patterns and processes, and delineating species' boundaries. Chapter two examines two competing hypotheses regarding conservation status of cave-dwelling species using a wide-ranging group of obligate subterranean crayfish species on the Cumberland Plateau's western escarpment. Using a population genetic approach, cave crayfish exhibited moderate to high levels of genetic diversity and attained large population sizes over their evolutionary histories. Phylogeographic analyses revealed that this crayfish assemblage originated along the northern end of the Cumberland Plateau and in leading-edge small steps, colonized southward and accumulated diversity along the way. Current species' boundaries do not match traditional morpho-species designations and also do not match current hydrological units. Chapter three explores phylogeography and habitat differences within the facultative cave-dwelling crayfish species Cambarus tenebrosus. This freshwater species is unique in that it inhabits surface and subsurface karst environments, has an unusually large distribution, and exhibits troglomorphism with reduced eyes and elongated limbs. Using sequence data from over 100 sampled localities, mostly along the Cumberland Plateau, C. tenebrosus appears to have inhabited surface and subsurface biomes throughout its evolutionary history. Additionally, this species shows extremely high levels of genetic diversity and NCA revealed significant phylogeographic structure within the species, but there was no significant relationship between habitat and genetic structure. Chapter four examines the obligate cave crayfish assemblage, genus Cambarus, subgenus Aviticambarus, which ranges across the southernmost area of the Southern Appalachians, which is known to contain the highest species diversity of obligate terrestrial animals in the United States. The Aviticambarus assemblage is only currently known from 58 caves in Alabama and Tennessee, and with samples from half of the known sites, this study uncovered additional lineages previously obscured by convergent morphology. These species show low levels of genetic diversity and populations that do not appear to be expanding. Species' boundaries are supported by geologic and phylogeographic information, but not current drainage basin boundaries.
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Characterization of Vascular Plant Species Composition and Relative Abundance in Southern Appalachian Mixed-Oak ForestsHammond, Daniel N. Jr. 24 April 1998 (has links)
Eight study sites were established in mid-elevation, south aspect, mixed-oak forests in the Ridge and Valley and Allegheny Mountain physiographic provinces of Southwestern Virginia and West Virginia to address questions concerning the variability in species composition, richness, and relative abundance of vascular plant species in those communities. All forest strata were sampled using a nested plot design. Variability in species richness and species composition was found to be high. Total species richness values ranged from 84 to 273, and Sorrenson's Coefficient of Similarity index values indicated that approximately 46, 38, and 51 percent of the species in the overstory, mid-story, and herb stratum were the same among sites, respectively. However, despite differences in composition and richness, K-S tests revealed significant differences in the distribution of ranked relative abundance only in the mid-story at two sites. Differences did occur in the relative abundance of twelve growth form categories. While tree seedlings and perennial herbs dominated, on average, woody vines and fern species represented substantial coverage on sites in the Allegheny Mountains. Correlations among forest strata were weak. The greatest amount of variation in species richness was attributiable to the standard deviation of a forest site quality index (FSQI), which was thought to represent the variation in microtopography across each site. The lack of correlation and high variability in plant species richness and composition, despite similarities in topographic characteristics, reinforce the inherent weaknesses involved with using the chronosequence approach to studying ecological responses in the Southern Appalachian mixed-oak region. Future remeasurement and long term monitoring of these study sites, following the implementation of silvicultural manipulations, will provide the information needed to make inference on the effects of forest management practices on Southern Appalachian mixed-oak forests. / Master of Science
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An Evaluation of Species Richness Estimators for Tardigrades of the Great Smoky Mountains National Park, Tennessee and North Carolina, USABartels, Paul J., Nelson, Diane R. 01 January 2007 (has links)
For the past 5 years we have been conducting a large-scale, multi-habitat inventory of the tardigrades in the Great Smoky Mountains National Park (U.S.A.) as part of the All Taxa Biodiversity Inventory (ATBI) (see www.dlia.org). In terrestrial habitats, we collected moss, lichen, and soil samples from 19 permanent ATBI plots, representing all major land cover types within the park. Each ATBI plot is 100 × 100 m. In each plot, when available, 16 moss samples, 16 lichen samples, and 4 soil samples were collected in paper bags and air dried in the laboratory. Specimens were isolated with LudoxAM centrifugation, and for each sample up to 50 adults plus eggs were individually mounted on microscope slides in Hoyer's medium and identified using phase contrast and DIC microscopy. Additional collections were made in the limestone caves of the Cades Cove region of the park, bird nests, and 13 different streams. To date (1-Jun-06), 589 samples have been collected, and of these 401 have been analyzed, yielding a total of 8133 identifiable tardigrades or, in some cases, species groups. A total of 73 species have been found in the park, 14 of which we believe are new to science. Seven species richness estimators have been developed to predict total species richness (see EstimateS 7.5 software, viceroy.eeb.uconn.edu/ estimates), and these were evaluated by comparing predictions from half of our data to the actual numbers from the total database. The results of this comparison indicate that different estimators work best in different habitats. Using the best estimators in each habitat, EstimateS 7.5 indicates that a total of 96 species are likely to occur throughout the park. Thus, Great Smoky Mountains National Park tardigrade diversity represents 10% of the world's known tardigrade fauna.
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Petrologic Study of the Danburg, Sandy Hill, and Delhi Intrusions: Constraints on Magmatism in the Southern AppalachiansStrack, Cody M. 17 September 2015 (has links)
No description available.
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An analysis of solute transport on a harvested hillslope in the southern Appalachian MountainsMoore, Erin Amanda 06 June 2008 (has links)
Interest in transport of dissolved nitrogen (N) and carbon (C) in forested ecosystems is growing because of potential effects of these solutes on streamwater quality and implications for C sequestration. Additional research will further the understanding about the dynamics of these soil solutes, particularly in response to harvesting of forests. Also, the purported role of riparian buffers, where logging is restricted along stream channels, in retaining soil solutes is not well studied in the steeply sloping terrain of the southern Appalachian Mountains. I examined solute transport in a first-order watershed in the Nantahala National Forest in North Carolina that was harvested in February 2006 with retention of a 10-m riparian buffer.
To quantify the movement of dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON), and dissolved organic carbon (DOC), four transects of lysimeters, approximately 30 m apart, were installed perpendicular to the stream on one hillslope. Porous ceramic cup (2-bar) lysimeters were installed in each transect 1, 4, 10, 16, 30, and 50 m from the stream in the A horizon and B horizon, and 4, 16, and 50 m from the stream in the saprolite layer. Samples were removed from the lysimeters 24 hr after 50 centibars of tension were placed on them, and riparian groundwater well and stream samples were collected at the same time as lysimeter samples. Collection of samples from the lysimeters, wells, and stream occurred every four to six weeks for one calendar year beginning March 2007. A 16-wk laboratory N mineralization study was conducted on A horizon soils.
Mean nitrate values in the soil solution of the A horizon in the spring were 1.53mg-N/L and decreased through the growing season to 0.030mg-N/L. Mean soil solution nitrate values in the B horizon and saprolite layer were 0.40mg-N/L in the spring and summer and decreased to 0.031mg-N/L in the winter. Mean soil solution ammonium concentrations were higher in the A horizon (0.090mg-N/L) than the B horizon and saprolite layer (0.034mg-N/L) and were lowest during the summer and fall. Dissolved organic C was significantly higher in the A horizon, with values ranging from 2.3mg/L to 599mg/L, than in the relatively stable B horizon and saprolite (1.9mg/L to 36.6mg/L). Dissolved organic C was logarithmically correlated to DON (r2 = 0.64), and DON values were highest in the A horizon (0.70mg/L). Cumulative N mineralization potential ranged from 48.1mg-N/kg to 75.6mg-N/kg and was not a useful predictor for nitrate soil solution values.
Nitrate leached vertically, and a large percentage of nitrate was stored in the B horizon and saprolite. Ammonium, DON, and DOC did not appear to leach vertically because they did not increase in the B horizon or saprolite layer. Ammonium, DON, and DOC are less mobile in soil solution than nitrate. The 10-m riparian zone had little impact on nitrate, ammonium, DON, and DOC removal. Nitrate remaining in the A horizon was likely removed through plant uptake in the harvested area before reaching the riparian zone. There was no detectable difference between ammonium concentrations in the harvested area and riparian zone likely because of limited mobility. The riparian zone did not remove excess DON or DOC, and in some transects was a source of DON and DOC. Nitrate and DOC concentrations were highly variable among transects and locations within transects. This may be caused by sensitivity of these solutes to site heterogeneity. This suggests that a large number of lysimeters should be used to account for this variability in future studies to ensure accuracy.
This study observed limited vertical leaching of ammonium, DON, and DOC through the profile. However, excess nitrate was observed moving from the A horizon into the B horizon and saprolite layer, suggesting the potential for delivery to the stream via subsurface transport and the need for attenuation of nitrate by the riparian zone. Because of low concentrations of nitrate entering the riparian zone during this study, the capacity for riparian attenuation of nitrate was not demonstrated. / Master of Science
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Ruffed grouse natality, chick survival, and brood micro-habitat selection in the southern AppalachiansHaulton, G. Scott 30 June 1999 (has links)
Natality characteristics were calculated for 3 regions in the southern Appalachians (Ridge and Valley, Alleghany Plateau, and Ohio River Valley). I report data collected in the first 2 years of a long term (> 6 years) study conducted by the Appalachian Cooperative Grouse Research Project (ACGRP). Nesting rate, pooled over all regions, was 83.6% in 1997 and 79.7% in 1998. In the 2-year period, the Alleghany Plateau reported the highest nesting rate (97.6%) while the Ohio River Valley reported the lowest rate (54.2%). Overall hen success rates were 81.5% in 1997 and 56.9% in 1998. Yearling hen success rates were as high or higher than adults. Adult hen success was 85.7% in 1997 and 48.5% in 1998; yearling hen success was 86.7% in 1997 and 82.3% in 1998. Additionally, I found a lower renest rate (8% over 2 years) in the southern Appalachians than previous studies have reported. The mean first-nest clutch size in the southern Appalachian region was considerably lower (9.5, years and regions pooled) than that reported for other portions of ruffed grouse range. Recommendations are given on how ACGRP natality data collection may be improved in upcoming years.
Ruffed grouse chick survival estimates were calculated from data collected in the first 2 years of a long term ACGRP study as well as data collected separate from ACGRP protocol. First-week chick survival estimates ranged from 0.18 to 0.32 in 1997 and 0.45 to 0.48 in 1998. Late brood season survivorship values (0.11-0.13 at week 5, 0.07 at week 10) were considerably lower in the southern Appalachians than those reported from more northern portions of ruffed grouse range. Additionally, the mean number of chicks per brood in July was lower in the southern Appalachians than that reported in the Great Lakes region during July and August. Recommendations are given on how ACGRP chick count data collection may be improved in upcoming years.
I compared micro-habitat characteristics at known brood locations with randomly selected locations to determine which characteristics are selected by ruffed grouse hens and broods in the southern Appalachians. In the first half of the brood season (weeks 1-6) hens and broods selected sites with tall, complete, vegetative ground cover. Additionally, broods selected forested sites with a well-developed canopy, rather than areas affected by large canopy gaps or openings. Higher ground cover at brood sites may have been due to a lack of midstory structure. The abundance of arthropods, fruit, and forage at brood flush sites was higher during the first few weeks of the brood season; this was possibly due to flush sites being located in open, mid-age or mature forest. Several authors have speculated that as the chicks' diet shifts from primarily arthropods to fruit and forage at approximately 3 weeks of age, the habitat selected by hens and their broods may change to accommodate this dietary shift. In my study, a change in habitat selection did not occur between weeks 3 and 4 as expected but after week 6 and may indicate the chicks' dietary shift occurs later than some have predicted. / Master of Science
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Stand Dynamics in a Southern Appalachian Montane Pine Barren, Warm Springs Mountain, VirginiaPowers, John William 08 September 2010 (has links)
Virginia's only montane pine barren, located in the Warm Springs Mountain Nature Preserve in the Allegheny Highlands of western Virginia is likely threatened by successional changes initiated by a history of fire suppression. Dominated by early successional fire adapted species, such as dwarfed Pinus rigida (Mill.) and Quercus ilicifolia (Wangenh.), this shrubland is home to numerous rare plants and invertebrates. We used vegetation analysis and dendrochronology to document establishment and recruitment patterns and to identify successional trends at this site. Tree establishment of the dominant tree species (P. rigida and Quercus rubra L.) peaked following the last known fire event in the early 1930s. Vegetation analysis revealed an absence of P. rigida seedling recruitment as well as a low density of fire adapted species such as Q. ilicifolia. In contrast, Q. rubra is represented in a variety of age classes and shade tolerant trees such as Acer rubrum (L.) and Pinus strobus (L.) are beginning to establish. A dense understory of ericaceous shrubs and a thick litter layer appear to inhibit recruitment of P. rigida and other early successional species pointing to the need for active management in the form of prescribed burns, which have been effective in other pine barrens. / Master of Science
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Cultivating Local: Building a Local Food System in Western North CarolinaPerrett, Allison S. 01 January 2013 (has links)
This dissertation examines a movement in Western North Carolina to build a local food system, one grounded in the conditions and relationships of place. In 2000, Mountain Family Farms launched the Local Food Campaign to raise public awareness about the region's farms and farming heritage, to educate consumers about the benefits of buying food grown by local farms, and, ultimately, to build markets for locally grown food to sustain the region's farms. The campaign sparked a social movement and over a decade later local farms and locally grown food are a palpable feature of life in the mountains of Western North Carolina. This dissertation is the result of my tenure at the organization as an employee and four years of ethnographic research.
The primary objective of my research has been to understand how the Local Food Movement in Western North Carolina is interacting with and affecting the industrialized food industry at the local level. Drawing on perspectives within anthropology, sociology, political science, geography, feminist theory, and social movements theory and from the concepts of hegemony, cultural politics, place-making, and social capital, this dissertation understands the movement in Western North Carolina within a processual framework, an integral part of the hegemonic process, which struggles to define and legitimize the practices and ideas that govern way of life. To examine this process, my research has focused on the ways movement organizers create a movement culture and mediate a tension between the dual imperatives of engaging the dominant food system and protecting the integrity of movement goals. Equally, my research has focused on understanding the impacts of movement activities on the region's food system - on the perceptions and practices of consumers and farmers and of the businesses that serve and sell food in the region.
My dissertation reveals the significance of place-making to the strategies of movement organizers - grounding movement participants and observers in the particularities of place, developing a shared place-based consciousness, cultivating different economic subjectivities that affect different material impacts. My dissertation documents the hegemonic process - the encounter and interaction between movement meanings, ideas, and practices and those of the dominant, conventional food industry. Within this process, movement outcomes are the responses of movement organizers, participants, and observers as they mediate challenges and opportunities at the intersection of disparate ideas and practices. Within a dynamic movement, outcomes are both provisional and incremental, shifting in relation to emergent knowledge and perceptions and the actions they inform.
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Geochemical Signatures of Stream Capture in the Retreating Blue Ridge Escarpment, Southern Appalachian MountainsDuBose, David 08 August 2017 (has links)
Stream capture is a major driver of the retreat of the Blue Ridge Escarpment, but timescales of capture are not well understood. This study examines stream sediment geochemistry to establish a set of sediment source fingerprints which can be used to identify and date the capture of the Tallulah River. Statistical analyses show significant differences in U, Th, and certain REE enrichment. These differences result from variations in bedrock along the lengths of each river and a shift in relative stream powers after capture to favor mobilization or deposition of heavy elements. The observed differences should be sufficient to identify where Tallulah sediment appears in floodplains of the capturing Tugaloo River, facilitating future dating of the capture event. Understanding the timing of river capture will provide insight into the ongoing reshaping and redistribution of river systems and interactions of geomorphic processes in the continuing evolution of the southern Appalachian Mountains.
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