Browsing by Author "Kennedy, Lisa M."

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    A 1000-year sedimentary record of hurricane, fire, and vegetation history from a coastal lagoon in southwestern Dominican Republic
    LeBlanc, Allison Renee (Virginia Tech, 2011-03-24)
    Our knowledge of whether hurricanes cause lasting changes in forest composition and the patterns and role of fire in Caribbean dry forests are lacking. This project combines paleoecological and paleotempestological methods to document the disturbance and environmental history of the last 1000 yrs at Laguna Alejandro, situated in the lowland dry forests of arid SW Dominican Republic. I analyzed multiple proxy data sources of a 160 cm coastal lagoon sediment profile. High-resolution (1 cm) sampling for loss-on-ignition and magnetic susceptibility indicated multiple erosion and hurricane events, including a hurricane ~996 cal YBP, and several erosion events and hurricanes between ~321 cal YBP and present day. Pollen analysis documented 32 plant families with most levels dominated by pollen of Fabaceae (legumes), the Urticales order, and Cyperaceae (sedges), though families of upland and montane vegetation are also present ~510-996 cal YBP. All pollen slides contained microscopic charcoal indicating the occurrence of regional or extra-local fires over the last ~1000 yrs. Local fires, as indicated by macroscopic charcoal, occurred before ~434 cal YBP and may be tied to hurricanes, increased moisture in the region (thereby increased fuel and ignition chances), or prehistoric human activities. Pollen spectra representing periods before and after disturbance events were similar and may support the idea of forest resilience, but more samples are needed. Multiple erosion events between ~294 cal YBP and present may be tied to hurricanes or tropical storms and increasing late-Holocene aridity in the region as documented by several studies from the Caribbean.
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    A 4700-Year Record of Lake Evolution and Fire History for Laguna Limon, Dominican Republic
    McVay, Jason Lyle (Virginia Tech, 2013-05-23)
    Fire is a primary driver of environmental change that can originate from natural or human ignition. Macroscopic charcoal (>125 "m) deposited into lake sediment is a record of a local fire event, whereas microscopic charcoal indicates fire activity on a broad landscape scale. Patterns of charcoal deposition may shed light on both human activities and climate history over long-time scales. Whether lowland Caribbean forests have experienced natural fire regimes over the long-term is unknown. Laguna Limón is a little-studied, large, freshwater lake on the northeastern coast of the Dominican Republic. We extracted four overlapping sediment cores totaling 315 cm in depth, and conducted analysis of macroscopic charcoal (2-cm), microscopic charcoal (16-cm), and loss-on-ignition (1-cm) to examine the long-term fire and environmental history of the area. Loss-on-ignition data established that the lake has only recently become organic rich, and was likely open to the sea as a low energy bay until 1400 Cal. Yr BP. The lake existed briefly as a wetland before transitioning to the modern freshwater lake 1200 Cal. Yr BP. Macroscopic charcoal was most abundant in the freshwater section of the core while microscopic charcoal peaked near the bottom of the core, and aligns well with other regional microscopic charcoal records. Overall the charcoal record reflects a combination of climatic and anthropogenic related charcoal deposition suggesting that fire has played an active role in the environmental history Laguna Limón.
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    Agricultural practices and perceptions of climate change in Keur Samba Guéye village, Senegal, West Africa
    Diaw, Adja Adama (Virginia Tech, 2013-06-11)
    This research uses a mixed methods approach to analyze recent climate and land use changes, and farmers\' perceptions of climate change and its impacts on traditional agriculture in the village of Keur Samba Guéye (KSG). This work looks at the influence of social beliefs in adoption of new strategies by small farmers in this region, a topic that has received little or no study to date. Traditional agriculture in KSG is not very productive at present because of the impoverishment of the area and traditional agricultures strong dependency on natural climatic conditions. In this research, I identified recent climatic trends, documented changes in land use/land cover (LULC) from 1989 to 2011, and assessed farmers\' perceptions of climate change and their responses to such changes. To document climate trends and LULC, I analyzed climate data of twelve meteorological stations located across the country and created a classification of satellite images of KSG for two time periods. To examine farmers\' perceptions and agricultural practices, I conducted surveys of the farmers of KSG and in surrounding villages. Most farmers reported negative impacts of climate change on their agriculture activities, and interest in adopting new agricultural strategies despite long-standing tradition. Increasing temperatures and irregularity of rainfall may have negatively impacted crop yields, but more climate data are needed to clarify this phenomenon. LULC has been influenced by both climate change and human pressure; agricultural land has declined, while bare soils have increased. Several recommendations are provided that may help farmers to cope with changing climate.
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    An Analysis of Shoreline Change at Little Lagoon, Alabama
    Gibson, Glen R. (Virginia Tech, 2006-06-20)
    In Alabama, the term "coastal shoreline" applies to the Gulf shoreline and the shorelines of estuaries, bays, and sounds connected to the Gulf of Mexico and subject to its tides. However, Alabama shoreline studies have yet to include Little Lagoon, which has been connected to the Gulf of Mexico for most of the last 200 years, according to historical charts. This study used historical nautical charts, aerial photographs, and LIDAR derived shorelines from 1917 to 2004 to analyze shoreline change on Little Lagoon and its adjacent Gulf shoreline. The high water line was used as the common reference feature, and all shorelines were georeferenced, projected, and digitized in a Geographic In-formation System. Between 1917 and 2001, the Gulf shoreline eroded an average of 40 m over 12.7 km, with some transects eroding almost 120 m while others accreted almost 60 m. The greatest changes to the Gulf shoreline were found near natural inlets, downdrift of jetties, and coincident with nourishment projects. Between 1955 and 1997, Little Lagoon shrank 0.5%, or 51.4 km², from 10,285.9 km² to 10,234.5 km². The greatest changes to Little Lagoon were found on its southern shoreline and near inlets, human development, and hurricane overwash fans. A correlation analysis conducted on the Gulf shoreline and Little Lagoon' s southern shoreline indicated that although weak overall correlation values exist when the entire 12.7 km study area is compared, strong correlation values are obtained in some areas when compared over one kilometer sections. The strongest correlations were found in the same locations as the greatest changes.
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    Analysis of Sinkhole Susceptibility and Karst Distribution in the Northern Shenandoah Valley, Virginia: Implications for Low Impact Development (LID) Site Suitability Models
    Hyland, Sara Elizabeth (Virginia Tech, 2005-05-13)
    Increased stormwater runoff due to urban development in the northern Shenandoah Valley (NSV) region of Virginia has prompted local officials and representatives to consider Low Impact Development (LID) as a stormwater management technique. LID is based on infiltrating stormwater runoff at the source through practices such as bioretention, rain gardens, and grass swales. The karst terrain that underlies the Shenandoah Valley presents a major barrier to the use of LID. Infiltration of surface runoff in karst landscapes may threaten groundwater quality and the stability of the bedrock. In 2004 the Center for Geospatial Information Technology (CGIT) at Virginia Tech developed an LID site suitability model for the NSV region incorporating karst as a key component in distinguishing unsuitable from suitable conditions for LID. But, due to the difficulty of mapping karst, the karst layer used in the site suitability model is very coarse in resolution, based primarily on carbonate versus non-carbonate rock. This study uses a 1:24,000 scale sinkhole map derived from sinkhole boundaries identified by geologist David Hubbard (1984) of the Virginia Department of Mines and Minerals (DMME) to develop a more detailed karst map for a sub-watershed of the NSV region. The analysis uses geospatial techniques to determine the relationship between sinkhole distribution and four major landscape factors: bedrock type, soil depth to bedrock, proximity to geologic faults, and proximity to surface streams. The analysis identified three major trends in sinkhole occurrence: (1) sinkholes are more abundant in relatively pure carbonate rocks of Ordivician age; (2) sinkhole occurrence increases with proximity to fault lines; and (3) sinkholes are sparse near streams, most abundant 600 to 1400 feet away from surface streams. Based on these findings a sinkhole susceptibility index was produced using weighted overlay analysis in ArcGIS. The sinkhole susceptibility index provides a more detailed karst layer for the LID site suitability maps and can be used by the NSV region as a predictive tool for future sinkhole occurrence.
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    Analysis of Sinkhole Susceptibility and Karst Distribution in the Northern Shenandoah Valley, Virginia: Implications for Low Impact Development (LID) Site Suitability Models
    Hyland, Sara Elizabeth; Kennedy, Lisa M.; Younos, Tamim M.; Parson, Shane (Virginia Water Resources Research Center, 2006-08)
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    Assessing Tree Mortality in a Southern Appalachian Red Spruce Forest using UAV-Survey Derived Orthoimagery
    Harris, Ryley C.; Kennedy, Lisa M.; Atkins, Maya (2020-11-06)
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    Assessment of Canopy Health with Drone-Based Orthoimagery in a Southern Appalachian Red Spruce Forest
    Harris, Ryley C.; Kennedy, Lisa M.; Pingel, Thomas J.; Thomas, Valerie A. (MDPI, 2022-03-10)
    Consumer-grade drone-produced digital orthoimagery is a valuable tool for conservation management and enables the low-cost monitoring of remote ecosystems. This study demonstrates the applicability of RGB orthoimagery for the assessment of forest health at the scale of individual trees in a 46-hectare plot of rare southern Appalachian red spruce forest on Whitetop Mountain, Virginia. We used photogrammetric Structure from Motion software Pix4Dmapper with drone-collected imagery to generate a mosaic for point cloud reconstruction and orthoimagery of the plot. Using 3-band RBG digital orthoimagery, we visually classified 9402 red spruce individuals, finding 8700 healthy (92.5%), 251 declining/dying (2.6%), and 451 dead (4.8%). We mapped individual spruce trees in each class and produced kernel density maps of health classes (live, dead, and dying). Our approach provided a nearly gap-free assessment of the red spruce canopy in our study site, versus a much more time-intensive field survey. Our maps provided useful information on stand mortality patterns and canopy gaps that could be used by managers to identify optimal locations for selective thinning to facilitate understory sapling regeneration. This approach, dependent mainly on an off-the-shelf drone system and visual interpretation of orthoimagery, could be applied by land managers to measure forest health in other spruce, or possibly spruce-fir, communities in the Appalachians. Our study highlights the usefulness of drone-produced orthoimagery for conservation monitoring, presenting a valid and accessible protocol for the monitoring and assessment of forest health in remote spruce, and possibly other conifer, populations. Adoption of drone-based monitoring may be especially useful in light of climate change and the possible displacement of southern Appalachian red spruce (and spruce-fir) ecosystems by the upslope migration of deciduous trees.
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    An Assessment of Non-Apis Bees as Fruit and Vegetable Crop Pollinators in Southwest Virginia
    Adamson, Nancy Lee (Virginia Tech, 2011-02-03)
    Declines in pollinators around the globe, notably the loss of honey bees (Apis mellifera L.) to Colony Collapse Disorder, coupled with a dearth of quantitative data on non-Apis bee pollinators, led to this dissertation research, which documents the role of non-Apis bees in crop pollination in southwest Virginia. Major findings of this first study of its kind in the region were that non-Apis bees provided the majority of pollination—measured by visitation—for several economically important entomophilous crops (apple, blueberry, caneberry, and cucurbits); diverse bee populations may be helping to stabilize pollination service (105 species on crop flowers); landscape factors were better predictors of non-Apis crop pollination service than farm management factors or overall bee diversity; and non-Apis bees in the genera Andrena, Bombus, and Osmia were as constant as honey bees when foraging on apple. Non-Apis, primarily native, bees made up between 68% (in caneberries) and 83% (in cucurbits) of bees observed visiting crop flowers. While 37–59 species visited crop flowers, there was low correspondence between bee communities across or within crop systems ("within crop" Jaccard similarity indices for richness ranged from 0.12–0.28). Bee community diversity on crop flowers may help stabilize pollination service if one or more species declines temporally or spatially. A few species were especially important in each crop: Andrena barbara in apple; Andrena carlini and A. vicina in blueberry; Lasioglossum leucozonium in caneberry; and Peponapis pruinosa and Bombus impatiens in cucurbits. Eight species collected were Virginia state records. In models testing effects of farm management and landscape on non-Apis crop pollination service, percent deciduous forest was positively correlated in apple, blueberry, and squash, but at different scales. For apple and blueberry, pollination service declined with an increase in utilized alternative forage but was positively related to habitat heterogeneity. For squash, percent native plants also related positively, possibly due to increased presence of bumble bees in late summer. Species collected from both bowl traps and flowers was as low as 22% and overall site bee diversity had no effect on crop pollination service, highlighting the value in pollination research of monitoring bees on flowers.
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    Beaver-driven dynamics of a peatland ecotone: Identification of landscape features with Lidar and geomorphon analysis
    Swift, Troy P.; Kennedy, Lisa M. (Virginia Tech, 2021-04-30)
    Beaver are renowned for their role as ecosystem engineers. Their ponds and vegetation consumption can greatly alter local hydrology and ratios of meadow to woodland. Beavers also actively buffer their environments against drought and wildfire susceptibility, and influence important climate parameters like carbon retention and methanogenesis (Rozhkova-Timina et al. 2018). This investigation focuses on beaver impacts on the boreal peatland ecotones enmeshing Cranberry Glades Botanical Area (~300 ha, ~1000 masl), a National Natural Landmark in mountainous West Virginia. Beaver activity has been suggested (Stine et al. 2011) to have an important role in the formation and maintenance of peatland conditions at Cranberry Glades. Using Lidar, geomorphon analysis, and aerial imagery, we were able to identify and reconstruct shifting hydrological patterns associated with beaver dams and ponds. The three-year interval worked well, allowing time for widespread changes in beaver infrastructure while conserving utility of reference imagery. Future work will include analysis of the most recent beaver activity, refinement of classification workflows, generation of more accurate physical models using drone-acquired Lidar and better ground filtering, and more complete incorporation of historical imagery.
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    Beaver-driven peatland ecotone dynamics: Impoundment detection using Lidar and geomorphon analysis
    Swift, Troy P.; Kennedy, Lisa M. (Ecological Society of America, 2021-08-05)
    Background/Question/Methods Beaver (Castor spp.) are renowned for their role as ecosystem engineers. Their ponds and vegetation consumption can greatly alter local hydrology and ratios of meadow to woodland. Beaver also actively buffer their environments against drought and wildfire susceptibility, and can influence important climate parameters like carbon retention and methanogenesis. Beaver impoundments tend to follow a multiyear cycle of construction, maintenance, degradation, and fallow. Flooding is the primary agent of destruction. This investigation focused on remotely detecting beaver impacts on the boreal peatland ecotones enmeshing Cranberry Glades Botanical Area, a National Natural Landmark in mountainous West Virginia adjacent to Cranberry Wilderness, and contained entirely by Monongahela National Forest. The Glades are perched at ~1000 m elevation and occupy ~300 ha. Literature suggests that beaver activity may have had an important role in the formation and maintenance of peatland conditions at Cranberry Glades. Aerial Lidar/photography were analyzed in tandem in order to identify and reconstruct shifting hydrological patterns associated with beaver dams and ponds. We rasterized aerial Lidar data from Nov/Dec 2018 for the entire Glades at 1-meter resolution, including a bare-earth Digital Terrain Model (RMSE vertical accuracy ~10cm) and a canopy height model sufficient to discern between trees, shrubs, and near-surface. We developed a novel method of geomorphon analysis to detect ponds and dams by exploiting their occupancy of the incised stream channels typical of these wetlands. Aerial color-infrared and RGB photography, gathered during a variety of seasons, enabled complementary identification of beaver-related infrastructure by visual inspection. Results/Conclusions Geomorphon DTM analysis successfully revealed low ridges closely bracketing inter-glade stream channels featuring free-flowing water, manifesting as a ridge/valley/ridge cross-channel sequence. This signal is conspicuously absent along stretches flooded by beaver ponds; an abrupt transition between the two states also occurs at dams. A survey using these methods counted 13 ponds in Winter 2013-14 and 17 ponds in Summer 2016. This multi-year interval worked well, allowing time for widespread changes in beaver infrastructure while conserving utility of reference imagery. Future work will include analysis of the most recent beaver activity, refinement of classification workflows, generation of more accurate physical models using drone-acquired Lidar, and more complete incorporation of historical imagery. Much remains to be understood about the full role of beaver in this rare and imperiled ‘Arctic island’ of the southern High Alleghenies.
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    Beaver-Driven Peatland Ecotone Dynamics: Impoundment Detection Using Lidar and Geomorphon Analysis
    Swift, Troy P.; Kennedy, Lisa M. (MDPI, 2021-12-03)
    This investigation focused on remotely detecting beaver impoundments and dams along the boreal-like peatland ecotones enmeshing Cranberry Glades Botanical Area, a National Natural Landmark in mountainous West Virginia, USA. Beaver (Castor spp.) are renowned for their role as ecosystem engineers. They can alter local hydrology, change the ratios of meadow to woodland, act as buffers against drought and wildfire, and influence important climate parameters such as carbon retention and methanogenesis. The Cranberry Glades (~1000 m a.s.l.) occupy ~300 ha, including ~40 ha of regionally rare, open peatlands. Given the likely historical role of beaver activity in the formation and maintenance of peatland conditions at Cranberry Glades, monitoring of recent activity may be useful in predicting future changes. We analyzed remotely sensed data to identify and reconstruct shifting patterns of surface hydrology associated with beaver ponds and dams and developed a novel application of geomorphons to detect them, aided by exploitation of absences and errors in Lidar data. We also quantified decadal-timescale dynamics of beaver activity by tallying detectable active impoundments between 1990–2020, revealing active/fallow cycles and changing numbers of impoundments per unit area of suitable riparian habitat. This research presents both a practical approach to monitoring beaver activity through analysis of publicly available data and a spatiotemporal reconstruction of three decades of beaver activity at this rare and imperiled “Arctic Island” of the southern High Alleghenies.
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    A Dendrochronological Analysis of Vegetation Change and Climate History in Two Southern Appalachian Balds, Craggy Gardens and Big Bald, NC
    Crawford, Christopher John (Virginia Tech, 2007-04-06)
    In the southern Appalachians, unforested openings known as balds persist on or near mountain peaks. These high elevation openings support a variety of unusual biota and are considered globally rare as a result of their biodiversity. Balds have historically been subject to both natural and human disturbances. Such historical and more recent disturbances have had a profound impact on vegetation dynamics in these systems. With the use of dendrochronology and GIS, this research project was aimed at 1) reconstructing the temporal and spatial patterns of tree encroachment into Craggy Gardens, a grass/heath bald, and determining the causal factors, and 2) investigating tree-growth responses of Quercus rubra L. to climatic factors at Craggy Gardens and Big Bald, North Carolina (high elevation forest-grass ecotones). Results indicate that historical grazing and land management have been responsible for vegetation changes at Craggy Gardens, in particular the advancement of Quercus rubra L. into the grass bald. Dendrochronological analyses showed that incremental growth of Quercus rubra L. growing in and adjacent to the balds was controlled by spring temperatures and drought conditions over most of the past century, until around 1970, when tree began responding primarily to growing year summer temperatures over the last four decades. This study concluded that land-uses overprinted on climatic conditions have governed local-scale vegetation structure over the past 150 years and without continuing management, trees may continue to advance into Craggy Gardens. Changing human disturbances along with observed climate changes in recent decades provides will most assuredly set the stage for future vegetation changes in southern Appalachians balds.
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    A Denroecological Analysis of Disturbance of Remnant Pinus Palustris, Southeastern Virginia
    Bhuta, Arvind Aniel Rombawa (Virginia Tech, 2006-04-28)
    Pinus palustris Miller (longleaf pine), in Virginia, is at the northernmost extent of its range. During presettlement times, this species occurred throughout the Piedmont and Coastal Plain of Virginia in pure and mixed stands, covering 607,000 hectares. This forest type has since been reduced to 81 hectares or 0.01% of its former range. Around 5,000 individual Pinus palustris remain on six sites in the coastal plains. Seacock Swamp and Everwoods are both sites known to have naturally regenerated Pinus palustris native to Virginia occurring in mixed-species stands. At both sites, I measured height and diameter of all Pinus palustris and cored individuals greater than 10 cm in diameter at breast height. A total of 71 trees were cored; the cores were crossdated and measured and crossdating was verified with the COFECHA program. A strong competition signal within the tree ring records at both sites signified the importance of stand dynamics on Pinus palustris in second-growth loblolly pine stands. These results are probably due to the mix of species within these stands and competition from loblolly pine as both the dominant understory and overstory species. Using Black and Abrams (2003) boundary line method, we calculated release and suppression events from the tree-ring record over the last century and found a very dynamic system. During the 1950s and 1960s, Seacock Swamp experienced major and moderate releases (23% moderate release and 18% major release in the 1950s and 33% moderate release and 49% major release in the 1960s) in response to a diameter-limit cut in 1953. Other major and moderate releases varied at both sites and may be attributed to different forest management practices that were in place throughout the last century however locating historical land use records to validate this was not possible at the present.
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    Estimating Hg Risk to the Common Loon (Gavia immer) in the Rangeley Lakes Region of Western Maine: A Regression Based GIS Model
    Kramar, David E. (Virginia Tech, 2004-04-21)
    This research relates Hg levels in the Common Loon (Gavia immer) to a variety of physical factors. Constructed within the framework of a GIS system, this model analyzes the spatial relationships and the influence of physical land cover factors as a function of distance from the individual loon territories. Thiessan polygons were used to generate the territory for each loon. Buffering of the thiessan polygons was done to establish the boundaries of the individual distance classes and to gather information on the percentage of individual land cover classes within each distance class. Information on precipitation was also gathered. Results from the regression analysis (R2 = 57.3% at the 150m distance class) performed on the variables suggest that the proximity of certain land use types such as cropland, shrub land, and wetlands influence the rates at which Hg is available within an individual territory. Within the 150m and 300m buffers, crop land, shrub land, and wetland exhibited the strongest relationship with the Hg levels in the common loon, with cropland exhibiting a negative relationship suggesting that the proximity of cultivated lands plays a role in decreasing the amount of available Hg in a territory.
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    Evaluation of Rainwater Harvesting on Residential Housing on Virginia Tech Campus
    McCloskey, Tara (Virginia Tech, 2010-04-29)
    Rainwater harvesting (RWH) refers to the collection of rainwater for subsequent on-site use. Rainwater is most often used for non-potable purposes including toilet flushing, laundering, landscape and commercial crop irrigation, industry, fire fighting, air-conditioning, and vehicle-washing. This study evaluates the potential impacts of RWH on residential housing on Virginia Tech campus in southwestern Virginia in regards to potable water offset, energy conservation, stormwater mitigation, carbon emission reduction, and financial savings. Potential rainwater collection was estimated from three simulations used to approximate the maximum, average, and minimum range of annual precipitation. Collected rainwater estimates were used to calculate the impacts on the areas of interest. Cumulatively, the sample buildings can collect 3.4 to 5.3 millions of gallons of rainwater — offsetting potable water use and reducing stormwater by an equivalent amount, save 320 to 1842 kWh of energy, and reduce carbon emissions by 650 to 3650 pounds annually. Cumulative savings for the nine buildings from combined water and energy offsets range between $5751 and $9005 USD, not substantial enough to serve as the sole basis of RWH implementation on campus. A significant advantage of RWH relates to the management and improvement of the Stroubles Creek watershed in which the majority of the campus sits. Additionally, RWH implementation would benefit sustainable initiatives and provide Virginia Tech additional opportunities for conservation incentives and environmental stewardship funding.
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    Forest dynamics of pine- and oak-dominated communities on southeastern-facing slopes of Warm Springs Mountain, Virginia
    Sams, Brent Shipley (Virginia Tech, 2012-06-01)
    Warm Springs Mountain (WSM), a priority conservation area for The Nature Conservancy in Bath County, Virginia, is home to a rare montane pine barren and large tracts of uninterrupted mixed pine and deciduous forest extending east into the George Washington National Forest. Limited documentation of past disturbances and their influence on WSM forests presents challenges for land managers desiring to understand historic conditions for these ecosystems. The only formal study of vegetation dynamics on WSM noted an absence of pitch pine (Pinus rigida Mill.) regeneration and an increase in fire-intolerant species during recent decades in the pine barren community that is probably linked to fire suppression. Dendrochronological studies of disturbance history in the central and southern Appalachians have mostly focused on ridgetop and southwestern-facing slopes. This study examines long-term forest dynamics in the pine- and oak-dominated forests on southeastern slopes of Warm Springs Mountain and downslope from the higher elevation pine barren using dendrochronology and vegetation analysis. We studied trees in six 20 x 50 m plots to develop a tree ring chronology and document changes in stand composition and structure through time. We found an increase in fire-intolerant species and decline in fire-dependent pines and oaks through time. Pitch pines have not recruited since 1954 in our sites due to a lack of burning, while Acer rubrum L. has produced high numbers of seedlings in recent years. This study of vegetation dynamics over space and time will provide insights for land managers and inform fire restoration practices.
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    Geographic Literacy and World Knowledge Among Undergraduate College Students
    Winship, Jodi M. (Virginia Tech, 2004-09-15)
    To succeed in today'­s globalized world, it is important to understand the places and cultures outside our own. Yet despite the acknowledged need for and importance of a greater understanding of the world, various surveys assessing geographic knowledge have demonstrated the geographic ignorance of people in the U.S. The purpose of this study is to assess the level of geographic literacy among undergraduate college students and to investigate factors that may influence geographic literacy. An on-line survey, adapted from the National Geographic/Roper 2002 Global Geographic Literacy Survey, was administered to a sample of undergraduate students at Virginia Tech. The survey included a geography "quiz" to assess knowledge of geography and world events and a background section to collect information about various factors that may influence the participants' geographic literacy. Over 400 students participated in the study. The data were statistically analyzed using the Mann-Whitney U and Kruskal-Wallis tests for differences in means. Contrary to much of the previous research, the participants in this survey demonstrated a good level of geographic knowledge. The mean score of the geography "quiz" was 81 percent. Some of the factors found to have influence on the scores were gender, international travel, major, fulfillment of Virginia Tech's Area 7 requirement, frequency of news media access, and type of news accessed. Age, academic class, GPA, residency status, junior/high school geography classes, international friends, and knowledge of foreign languages were found to have little or no influence."
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    Geospatial and field-based techniques for physical geography and environmental change
    Swift, Troy Phillip (Virginia Tech, 2023-10-11)
    This dissertation has primarily been an exercise in surveying interdisciplinary opportunities for further research within the doctoral program's overarching mandate of Geospatial and Environmental Analysis. To this end I have dedicated my efforts to the investigation of topics and themes that are relevant to my three specializations: physical geography, biogeography, and geospatial science. I share these efforts in the three following chapters, one of which is already published (Chapter 2), and the other two presented as manuscripts suitable for publication. These themes include historical and present hydrological patterns and drivers, hurricane disturbance of coastal forest, and evaluation of a Wisconsin geosite as a possible candidate for UNESCO Geopark designation. I chose study areas located in the eastern United States, including Appalachia, the Gulf Coast, and the Great Lakes region. Every chapter's work has been supported by an interdisciplinary array of methods with which I have striven to generate high-quality research from excitingly novel perspectives. All of my research has been pursued, and each resultant manuscript has been crafted, using methods and techniques from remote sensing and GIS including in-person fieldwork, smartphonesupported geolocation and photodocumentation, pattern analysis, statistical rigor, and indepth review and citation of extant literature. This research was carried out with deliberately minimal budgets that help offset costs of transportation and labor. I offer this dissertation as the ultimate fruits of my labor while here at Virginia Tech, composed of three interrelated yet reasonably stand-alone manuscript chapters that in turn more specifically address questions within the broader fields of biogeomorphology, dendrotempestology, and finally the geohumanities. Chapter 2 was published in an open-source peer-reviewed journal (Land, 2021: https://doi.org/10.3390/land10121333). My coauthors and I intend to publish the remaining two chapters in peer-reviewed journals. Therefore each manuscript herein provides its own Introduction, Methods, Results, Discussion, Conclusion, and References sections as set forth in the Table of Contents. Chapter 2 is a recently published study of historical beaver activity and hydrological patterns at the rare and imperiled Cranberry Glades Botanical Area, a high-elevation peatland in the Allegheny highlands of West Virginia. We used Lidar and Geomorphon analysis to reconstruct shifting patterns of surface hydrology associated with Beaver ponds and dams over the past three decades. Beavers play a large role in the formation and maintenance of peatland conditions and our work provides a novel method (geomorphons) for monitoring beaver activity into the future. In Chapter 3, we take advantage of wind-damaged leaning pine trees to reconstruct characteristics of landfalling Hurricane Sally (2020) along the Gulf coast of Florida/Alabama (USA). We employed a smartphone to measure and record the direction of lean on 556 pine trees in five sites in the eyewall-struck region. Using geometric analysis, we were able to locate the geographic center of the storm and the position and size of the area of highest speed winds in Sally's eyewall. We validated our results with independent data from official sources and found that our simple field-based analysis was surprisingly accurate. We think that our low-cost and relatively low-tech approach may be useful to inform hindcasts, provide quality input to models of future stand-damaging events, and even to enhance teaching and outreach efforts. Chapter 4 represents research aimed at producing an inventory and assessment of the Baraboo Hills in south-central Wisconsin (USA) as a potential candidate for a UNESCO Geopark. The basis for designation is a geographical area that contains geological heritage of international significance, but such a park's fuller mission according to its website is to "explore, develop and celebrate the links between that geological heritage and all other aspects of the area's natural, cultural and intangible heritages." We followed a published method, including field study, to inventory and assess 62 sites in and around the Hills for their scientific, educational, and touristic merit, and their risk of degradation. We provide these data and through spatial analysis, a proposed perimeter of the area that would benefit from unified protection.
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    Incorporating User Opinion into a New Wine Tourism Map for Southwest Virginia
    Pritchard, Katherine (Virginia Tech, 2008-12-10)
    Thematic tourist maps provide users with a tangible geographic route to their travel destinations and also may contain a wide variety of additional information to enhance traveler experiences. Unlike other types of maps that focus on accurate topographic representation of an area or on depiction of spatial data, tourist maps should be specifically constructed to appeal directly to the end-user. Toward that end, this research developed and implemented a model to incorporate user opinion on content, levels of detail, and labeling conventions during the process of designing and creating a wine tourism map for southwest Virginia. Over 700 (total) wine tourists completed brief questionnaires during five distinct phases of data collection and map modeling. At each point, we incorporated user input into map design for the preceding phase, and a final assessment surveyed tourist attitude of the finished product. Interestingly, surveys indicated a propensity for users to highly rank the idea of more and more detailed content data, as well as high levels of spatial detail, but when presented with the corresponding maps, they tended to favor a cleaner more simplified display. This finding underscores our conclusion that while user input is critical for developing successful tourist maps, cartographic training and skill is still required to achieve a quality product. Overall, the final map incorporating user input received overwhelmingly positive user reviews when compared to existing regional maps indicating that our iterative method of seeking user input at various stages of map development was successful, and facilitated creation of an improved product.