For this dissertation, I measured how plant communities in Appalachian forests responded to disturbances caused by forest management activities. I had two primary objectives including (1) testing theories of biological diversity and invasions by nonnative species; and (2) providing empirical data that will help guide the sustainable use of forest resources. This work is part of the Southern Appalachian Silviculture and Biodiversity (SASAB) experiment that was established in the early 1990s to investigate ecosystem responses to a gradient of timber harvesting disturbances. Ranging from undisturbed controls to silvicultural clearcuts, the disturbance gradient is replicated at sites located throughout the Appalachian mountains of Virginia and West Virginia. The plant community was sampled across a wide range of spatial scales (2 hectares to 1 m2) using a nested sampling design and was also sampled at three times including pre-disturbance, one year post-disturbance, and ten year post-disturbance. For one element of the study I tested modern theories of biological invasions and investigated how the forest disturbance gradient interacted with species diversity to influence invasion by nonnative species (Chapter 2). Contrary to popular ecological theories of biotic resistance, the most diverse sites tended to be more easily invaded following intense canopy disturbance. Interestingly, none of the sites in this study were dominated by invasive plants, which led me to ask whether dominant tree species in forests provided resistance to nonnative plant establishment and growth through the quality of the litter they produce. I also asked how might animals that are known to alter litter layers interact with dominant tree species to influence plant invasions. Therefore, I conducted an experiment investigating how changes in litter from dominant tree species and invasions by nonnative earthworms might influence invasibility of forests using forest floor mesocosms (Chapter 3). I found that plant invasion was inhibited by native oak litter even when earthworms were present, suggesting that oak forests may resist plant invasions via oak tree litter. In contrast, plant invasion was greater under invasive tree litter and earthworm activity tended to facilitate invasive plant success only under invasive tree litter. I was also interested in understanding how disturbance might alter relationships between local and regional diversity. The long-term data of the forest disturbance experiment allowed me to investigate how local species richness is mediated by regional species richness after disturbance and during forest community development (Chapter 4). Local richness depended strongly on regional richness only after disturbance via colonization of species, but this relationship changed during forest aggradation. These results suggest that regional species pools are important to maintain local diversity following disturbance, but that local interactions (through canopy closure of dominant trees) exert control over species diversity during community reorganization. Lastly, I tested current theories on how diversity influences compositional stability after disturbance (Chapter 5). Disturbance consistently resulted in decreased compositional stability, but diversity was associated with stability in complex ways, which depended on how stability was measured and at what scale. Species-rich areas were in some instances less stable; in other instances areas with intermediate levels of diversity were more stable. These results suggest that disturbance causes shifts in species composition via colonization, but the ways in which diversity of sites influences compositional stability is complex and depends on methods used and the scales of observation. Taken together, these results suggest that disturbance influences invasibility, species saturation, and compositional stability of ecological communities. These properties change immediately following disturbance, and during forest development and canopy closure. Data from this project were useful in testing existing theories of community ecology, and may ultimately prove useful for forest managers as they decide how to protect biodiversity while planning for other uses of forest resources. Overall, these results suggest that colonization of species is the primary process driving plant community patterns in Appalachian forests following disturbance. / Ph. D.

I investigated ruffed grouse (Bonasa umbellus) population ecology in the southern and central Appalachians as part of the Appalachian Cooperative Grouse Research Project (ACGRP). Several hypotheses have been offered to explain the low abundance of ruffed grouse in the region including inadequate quantity of early-successional forests due to changes in land use, additive harvest mortality, low productivity and recruitment, and nutritional stress. Through the cooperative nature of the ACGRP, researchers tracked >3,000 ruffed grouse between October 1996 and September 2002 and gathered data on reproduction, recruitment, survival, and mortality factors. As part of the ACGRP My objectives were (1) estimate reproductive rates, (2) estimate survival and cause-specific mortality rates, (3) determine if ruffed grouse harvest in the Appalachian region is compensatory, and (4) estimate ruffed grouse finite population growth. Ruffed grouse population dynamics in the Appalachian region differed greatly from the core of ruffed grouse range. In general, ruffed grouse in the Appalachian region had lower productivity and recruitment, but higher survival than reported for populations in the Great Lakes and southern Canada. However, within the southern and central Appalachian region, ruffed grouse population dynamics differed between oak-hickory and mixed-mesophytic forest associations. Productivity and recruitment were lower in oak-hickory forests, but adult survival was higher than in mixed-mesophytic forests. Furthermore, ruffed grouse productivity and recruitment were more strongly related to hard mast (i.e., acorn) production in oak-hickory forests than in mixed-mesophytic forests. The leading cause of ruffed grouse mortality was avian predation (44% of known mortalities). Harvest mortality accounted for only 12% of all known mortalities and appeared to be compensatory. Population models indicate ruffed grouse populations in the Appalachian region are declining, but estimates vary greatly stressing the need for improved understanding of annual productivity and recruitment. We posit ruffed grouse in the Appalachian region exhibit a clinal population structure and changes in life-history strategies due to gradual changes in the quality of food resources, changes in snow fall and accumulation patterns, and predator communities. Recommendations are presented for habitat and harvest management and future research and management needs. / Ph. D.

Ruffed grouse populations are low in Appalachian forests, possibly because low habitat quality negatively affects survival, condition, and reproduction. Through the Appalachian Cooperative Grouse Research Project (ACGRP) researchers tracked >1500 radioed grouse at 10 study sites (1996__2002). To improve our understanding of Appalachian grouse habitat ecology, I carried out two primary analyses of this database. First, grouse should be under selective pressure to minimize movements, so I studied factors associated with variation in home range size. Second, importance of a habitat is affected by an individual's resource needs, and I investigated factors associated with variation in selection of "preferred" habitats. Both approaches yielded important insights into the species' regional habitat ecology. As elsewhere, clearcuts, which afford escape cover, formed the cornerstone of grouse habitat in the region. However, a number of other factors were also important. At the root of this was a divergence in habitat ecology between grouse inhabiting the two major forest types in the region. In oak-hickory forests nutritional constraint strongly influenced habitat use. Grouse home ranges increased 2.5x following poor hard mast crops, and at these times grouse increased use of alternate foraging habitats. Grouse, especially females and broods, made extensive use of mesic bottomlands and forest edges, which in oak-hickory forests support relatively abundant soft mast and herbaceous forages. In contrast, grouse inhabiting mixed mesophytic forests were insensitive to hard mast, did not select bottomlands, reduced use of forest edges, and increased use of clearcuts. I feel that greater abundance of birch, cherry, and aspen, buds of which are a high quality winter food, relieves nutritional stress on grouse inhabiting mesophytic forests. A general inference was that grouse attempted to balance competing strategies of maximizing either survival or condition, and the expression of this tradeoff was mediated by forest composition. Also presented here were studies of radiotelemetry error, roost site selection, and suitability of prescribed burning as a habitat improvement technique. In the closing chapter I make recommendations for managing Appalachian forests for grouse, which focus on improving winter foraging habitat, brood habitat, and escape cover, all of which are limiting in Appalachian forests. / Ph. D.

The eastern Blue Ridge near Warrenton is composed of low grade metamorphosed and very little deformed clastic sedimentary rocks, which unconfomably overlie Middle and Late Proterozoic gneisses and granites. A thick succession of Late Proterozoic metavo1canics (Catoctin Formation) lies above the metasediments. The metasediments in the Warrenton area are the Lynchburg and Fauquier Groups, the latter of which is raised herein from a formation to a group. The lowest unit, the Bunker Hill Formation, is dominated by coarse- to very coarse-grained feldspathic sandstone, typically trough and planar cross-bedded, with minor fine-grained sandstone and siltstone or granule conglomerate. The overlying Monumental Mills Formation is dominated by thin bedded fine sandstone and siltstone, with minor laminated mudstone towards the top. The next overlying unit, Ball Mountain Formation, is composed of thick beds of medium to coarse sandstone and rare conglomerate, interbedded in black schists and dark laminated mudstones. The facies observed and correlation with previous work farther south suggests that these three formations record a continuous transgressive alluvial to deep water rift sequence. The Ball Mountain passes northwards to the lower Swains Mountain Formation, which is dominated by massive sandstone, and farther north to the upper Swains Mountain and Carter Run Formation, a continuous fining upwards succession from medium sandstone to laminated mudstone. From south to north the clastic sequence shows an overall thinning, and at the time of eruption of the Catoctin volcanics probably was shoaling as well. The overlying Catoctin shows a basal volcanic breccia unit covered by a thick succession of lavas. Medium grained, parallel bedded feldspathic sandstone occurs as lenses along a regionally continuous belt in the upper part of the formation. Numerous metamorphosed mafic intrusives were observed within the clastic sequence, and evidence for Late Proterozoic faulting was documented. The whole assemblage of lithofacies is interpreted to represent a continuous rift sequence, and the presently exposed section was probably oblique to the trend of the original rift. The rift stratigraphy can be traced in all the Warrenton area. The whole sequence is characterized by one low grade progressive metamorphism. Deformation is minimal and took place in two stages: Development of pervasive foliation (S 1) in varying degrees throughout the sequence (event: Dl). Subsequent folding and faulting and development of a localized discrete cleavage (S2) (event: D2). The observed structural features can be correlated with features described by other workers in adjacent areas. The map-scale structure is dominated by a change in attitude of the strata from east-dipping next to the basement, to open folded and gently dipping farther east. Considering that the whole Blue Ridge is an allochthonus thrust sheet, this change probably corresponds to the eastern subsurface edge of the basement block, on which the rift sediments were deposited, above a gently dipping decolement. Some workers have proposed tectonic models of the central Appalachians in which accreted terrane boundaries, are present along the eastern Blue Ridge. The continuous rift stratigraphy and the tectonic evolution proposed herein do not support such models. / Master of Science

Sediment is a prevalent non-point source pollutant associated with forest operations. Roads and skid trail surfaces have erosion rates that are greater than the harvest area. Forestry best management practices (BMPs) have been developed to minimize erosion on skid trails, but few projects have compared the effectiveness of different BMPs for bladed skid trails in the mountains. This project evaluated soil erosion rates from bladed skid trails in the Ridge and Valley physiographic region of Virginia following an operational timber harvest. Skid trails were assigned into six blocks where each block had similar slopes and soils. All BMP treatments had waterbars, which are considered the minimum acceptable BMP closure treatment. Each block contained four different skid trail closure BMP treatments (waterbar only (Control), slash-covered (Slash), seeded (Seed), and seeded with fertilizer and mulch (Mulch)). The 24 treatment units were isolated with waterbars and installed following the Virginia Department of Forestry (VDOF) BMP guidelines. The randomized complete block design had three slope class ranges: gentle (0%-10%), moderate (11%-20%), and steep (21%-30%). Stormwater runoff from skid trails was directed at downslope waterbars and eroded material was trapped in silt fences at each treatment area. Depth and area of eroded soil collected in silt fences was measured monthly to quantify total erosion volume for the skid trail area and converted to a per acre basis. Volumes were converted to mass using soil bulk density within the trapped sediment. Control treatments had an average erosion rate of 6.8 tons ac-1 yr-1, with rates up to 73.5 tons ac-1 yr-1 following installation and during extreme rainfall events. Seed treatments recorded an average erosion rate of 2.6 tons ac-1 yr-1, with rates reaching 27.2 tons ac-1 yr-1. Adding grass seed provided ground cover, but not consistently over time. Due to high rates of ground cover, the Mulch treatments averaged 0.5 tons ac-1 yr-1 with an extreme of 3.8 tons ac-1 yr-1. Slash treatments were found to reduce erosion rates to an average of 0.4 tons ac-1 yr-1, with the highest rate being 1.8 tons ac-1 yr-1. Site characteristics on experimental units were collected quarterly in order to model erosion rates with commonly used erosion models for forestland (USLE-Forest, RUSLE2, WEPP:Road). Direct erosion estimates were compared to erosion model predictions produced by USLE-Forest, RUSLE2, and WEPP:Road in order to partially confirm the relationship between sediment trap data and the models. Using multiple analyses it was determined that USLE-Forest and RUSLE2 predicted mean values that are more similar to the actual measured rates, RUSLE2 and WEPP:Road have better linear relationships to the measured rates than does USLE-Forest, and USLE-Forest was the most statistically similar to the measured data using a nonparametric Steel-Dwass Multiple Comparisons Test. All models performed inadequately when attempting to predict Control or Slash treatments; while all models performed the best at predicting Mulch treatments. / Master of Science

The Upper Devonian "Chemung" and Hampshire Formations of the southern Central Appalachian basin constitute the upper strata of an eastward thickening wedge of elastic sediment. The sediments comprising the "Chemung" and Hampshire, deposited on a low-gradient marine shelf and alluvial plain, respectively, are syn- to post-orogenic (Acadian), and were derived from the erosion of the Acadian Mountains to the east. Facies of the "Chemung" indicate deposition within three major, laterally adjacent environments. The predominating facies assemblage constitutes upward-coarsening sequences interpreted as offshore to upper shoreface progradational successions. The sequences are storm- and wave-dominated and pass upward into storm- and wave-dominated shoal water delta facies or into low-energy subtidal to supratidal mudflat facies. The absence of beaches and tidal channels is indicative not only of low tidal ranges, but also of seaward dissipation of wave-energy within a very shallow intracratonic foreland basin. The easternmost sections of the Hampshire Formation are comprised of fluvial cycles interpreted as high-energy sheetflood deposits.This style of sedimentation developed in closest proximity to the source. The Hampshire of more western sections is constructed predominantly of cycles interpreted as low-sinuosity braided stream deposits with a lesser abundance of cycles deposited by high-sinuosity meandering streams and high-energy sheetfloods. Low depositional slopes were associated with the alluvial plain. Braiding, however, was probably due to high runoff associated with high rainfall in a tropical climate and inadequate floodplain stabilization by vegetation, resulting in periodic high discharge. / Master of Science

The expansion and proliferation of reactive nitrogen (N) sources, predominantly fertilizer application and fossil fuel combustion, has enriched the earth with N and acidified ecosystems. Acid rain is a primary vector of both N fertilization and acidification, initiating a cascade of consequences that alter biogeochemical cycling and global biological structure and function. Studies on N and acid influences are however rarely linked despite their common source. We used a wide, chronic gradient of N deposition (5.5 – 31 kg N ha⁻¹ yr-1) to explore patterns in carbon (C) and N cycling in light of recognized biogeochemical responses to acidic deposition. Specifically, we examined the response of key controls on dissolved C and N stability because soluble pools are involved in decomposition and nutrient recycling, the formation of soil organic matter (SOM), and the translation of elements through the biogeochemical continuum from atmospheric to soil to water. Results suggest that N deposition led to reduced organic matter C/N, enhanced net nitrification, and greater DON generation; and, these patterns were associated with changes in C composition. Conversely, physiochemical processes in the mineral soil seemed to control organic matter dynamics, with effects on N processing. Moreover, pH dependent controls on DOC stability were evidenced by changes in DOC concentration, chemical complexity and recalcitrance. These horizon-specific, differential responses to acid rain indicate that changes in the forest floor N economy were responsible for increased surface water NO3-N concentrations, whereas enhanced organomineral stability of DOC caused a significant increase in DOM concentrations in export. / Master of Science

Cold-air damming (CAD) is a prevalent Mid-Atlantic United States weather phenomenon that occurs when cold, dense air is dammed alongside the eastern slopes of the Appalachian Mountains. Lower-than-normal maximum temperatures, increased and prolonged cloud cover, and precipitation that produces hazardous impacts are common features of this weather event, which are well known for presenting difficulties to both human forecasters and weather prediction models. This study explores CAD events between 2007 and 2016 archived in a Blacksburg National Weather Service ‘bust’ database – instances when forecasters erred by at least 8°F (4.4°C) on either maximum or minimum daily air temperature. The database includes the temperature error within Model Output Statistics (MOS) guidance in association with these forecast ‘busts.’ During the 10-year study period, MOS guidance produced warm-biased maximum temperatures and cold-biased minimum temperatures for most of the problematic CAD events, suggesting MOS guidance tended to underestimate the strength of CAD in these cases, seeming to struggle with weaker CAD events. During CAD erosion, MOS tended to prematurely erode CAD scenarios at night and predicted them to persist for too long during the day. Hourly surface meteorological and synoptic atmosphere composites during these ‘busted’ CAD events failed to reveal obvious differences from what is expected for central Appalachian CAD. However, a comparison to well-forecast classic cold-season CAD events suggest that busted cases of this same type of CAD may be drier than is typical. As the atmospheric patterns associated with busted CAD events are typical of the phenomenon, but a bit weaker or more marginal, forecast errors appear to stem from subtle model errors rather than forecaster error. It is possible that the models may inadequately characterize low-level moisture, but further research is needed to isolate the source of model forecast error. Nonetheless, the results of this research serve as guidance for operational forecasters as they consider model guidance during weak CAD events. / Master of Science / Cold-air damming (CAD) is a common weather pattern that affects the Blue Ridge Mountain region of the eastern United States, in which cold air at the atmosphere’s surface is directed from the Northeast and is dammed against the eastern Appalachian Mountains. This weather event causes lower-than-normal temperatures over the region and is often characterized by prolonged cloudy skies and precipitation. CAD is very difficult for forecasters to accurately predict, as they rely on weather forecast models that often simulate these situations poorly. CAD also strains emergency managers who rely on accurate forecasts to support public safety during CAD. This study explores CAD events between 2007 and 2016 archived in a Blacksburg National Weather Service ‘bust’ database – instances when forecasters erred by at least 8°F (4.4°C) on either maximum or minimum daily air temperature. The database includes the temperature error within Model Output Statistics (MOS) guidance in association with these forecast ‘busts.’ During the 10-year study period, MOS guidance forecasted maximum temperatures too high and minimum temperatures too low for most of the problematic CAD events, suggesting MOS guidance tended to underestimate the strength of CAD in these cases, seeming to struggle with weaker CAD events. During instances where CAD dissolved from the Appalachians, MOS tended to prematurely erode CAD scenarios at night and predicted them to persist for too long during the day. Hourly surface meteorological and synoptic atmosphere composites during these ‘busted’ CAD events failed to reveal obvious differences from what is expected for central Appalachian CAD. However, a comparison to well-forecast classic cold-season CAD events suggest that busted cases of this same type of CAD may be drier than is typical. As the atmospheric patterns associated with busted CAD events are typical of the phenomenon, but a bit weaker or more marginal, forecast errors appear to stem from subtle model errors rather than forecaster error. It is possible that the models may inadequately characterize low-level moisture, but further research is needed to isolate the source of model forecast error. Nonetheless, the results of this research serve as guidance for operational forecasters as they consider model guidance during weak CAD events.

The purpose of this study was to describe the migration of a selected group of church members from their Appalachian counties of origin to Muncie, Indiana, with specific attention being given to religious beliefs, causes for migration, urban residential patterns, the degree of occupational mobility, and the establishment of migrant churches. The sample studied consisted of members of four migrant churches that had been founded between 1936 and 1959. The migrants' Appalachian origins were obtained from the records of transfers of membership from their original church to the one in Muncie. Tabulation of these transfers revealed that 90.1 percent of them came from four counties: McCreary and Wayne in Kentucky, and Fentress and Scott in Tennessee.Data on living conditions in these Appalachian counties were derived from census material, with detailed attention being given to population, birth rates, economy, employment, education, and housing. The impact these factors had on migration was evaluated. Information as to the migrants' residential patterns and occupational mobility was drawn from the censuses and Muncie city directories. The rates of residential and occupational mobility were determined by examining data at five-year intervals beginning with 1940.The role played by religion in the area of the migrants' origin also was explored. Extensive treatment was given to the establishment of migrant churches and their role in the migration process. Church records and interviews were used to describe the founding of churches as well as how they compared with their counterparts in Appalachia.One of the findings of this study is that a decline in coal mining and subsistence farming was not the chief factor accounting for migration from this four-county region. In the 1940s the decline in these two categories of employment only accounted for 18 percent of the out-migration. But in the following decade, they did account for 58 percent of the exodus. Census data before 1950 indicated that more jobs in other categories had lessened the impact of mining and agriculture on migration. However, after 1950 employment in other categories also declined, making migration even more pronounced.The chief factor responsible for migration from this area was the high rate of natural increase. Birth rates were twice as high as the national average and half of these counties' inhabitants were under twenty years old. Population pressure existed because the economy could not absorb the annual increase. Approximately 60 percent of the out-migration resulted from this high rate of natural increase.An investigation of residential patterns did not reveal the clustering of migrants within city blocks. Instead, concentrations of migrants were found within larger housing districts. They tended to move into the central part of the city as well as four other districts with substandard housing. When those areas filled up, they moved over into the southeast side. Significant concentrations were also found in the Black areas.Study of the migrants' occupational patterns revealed only marginal mobility. All of them started as unskilled or semi-skilled laborers, with only 8.4 percent improving their position over the thirty-five year period studied. The latter were upgraded as industrial supervisors or skilled laborers. However, none of the migrants became white-collar employees or managed to move into new or elaborate housing. Overall, these people have preferred the step-by-step marginal advancements that are consistent with their culture.The most significant fact about these migrant churches is that they were established and are maintained by extended family groups which originated and still have deep roots in Appalachia. Urbanization was found to have had some impact in the sense that they eventually had adopted more church programs, more worship services, and full-time ministers like other urban churches. However, in their basic religious practices and beliefs, and in the way they depend upon bonds of kinship these churches still reflect many of the basic characteristics of those back in Appalachia.

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