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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.
1

Efficacy of in situ artificial refugia to increase recruitment of the Barrens topminnow in the presence of invasive western mosquitofish a thesis presented to the faculty of the Graduate School, Tennessee Technological University /

Watts, Allison V. January 2009 (has links)
Thesis (M.S.)--Tennessee Technological University, 2009. / Title from title page screen (viewed on June 29, 2010). Bibliography: leaves 21-25.
2

Assessment of exhaustion-threshold curves for fish volitionally swimming in culverts a thesis presented to the faculty of the Graduate School, Tennessee Technological University /

Harvey, James A., January 2009 (has links)
Thesis (M.S.)--Tennessee Technological University, 2009. / Title from title page screen (viewed on Aug. 19, 2009). Bibliography: leaves 37-41.
3

From Parlor to Forest Temple: An Historical Anthropology of the Early Landscapes of the National Camp-Meeting Association for the Promotion of Holiness, 1867-1871.

Avery-Quinn, Samuel John 01 May 2011 (has links)
This dissertation is an historical anthropology investigating the late 19th century liturgical landscapes of the National Camp‐Meeting Association for the Promotion of Holiness, an organization of Methodist clergy who sought ecclesiastical and social reform primarily through camp‐meeting revivals promoting the experience of entire sanctification. National camp meetings drew from the liturgical and architectural traditions of early 19th century frontier revivalism, yet, as this dissertation argues, these meetings were not simply an appropriation of the structure of Second Great Awakening revivals for the purpose of promoting holiness theology in decidedly more urban areas of the Northeast and Mid‐Atlantic. Rather, these meetings were a (re)imagining of the cultural practice of the camp‐meeting through a Victorian system of symbolic meanings, a middle‐class, (ex)urban geographic context, and a distinctive set of liturgical performances, social interactions, and cognitive‐environmental and architectural cues designed to elicit a changed subjectivity among attendees. Each of these transformations shaped the social space, architectural configuration, and site selection of the liturgical landscapes of the National Camp‐Meeting Association, and it is these spatial and material traces that offer a substantial body of data for the interpretation of past religious and ritual landscapes in North America. Such interpretation of revival landscapes is possible through a process of cross‐mending archival sources (diaries, autobiographies, biographies, historic correspondence, newspaper reports, sermon texts, organizational documents, maps, photographs), material culture, archaeological reports, geo‐spatial and environmental data to reconstruct and thickly interpret the ritual landscapes of three early meetings of the National Camp‐Meeting Association for the Promotion of Holiness – Vineland, New Jersey, Manheim, Pennsylvania, and Round Lake, New York. In its results, this dissertation argues for a significant connection between Methodism, geographic regions, and 19th century holiness practices, and an interpretation of holiness revivalism as a means of renegotiating moral orders amidst industrialization, urbanization, vacationing, and changing social fault lines in the church including race and gender.
4

XERIC LIMESTONE PRAIRIES OF EASTERN UNITED STATES

Lawless, Patrick Joseph 01 January 2005 (has links)
Xeric limestone prairies (XLPs) are open, nonforested communities dominatedby native, C4 perennial grasses. In eastern United States, they occur on shallow, rockycalcareous soils in various physiographic provinces from Missouri and Pennsylvaniasouth to Arkansas and Georgia. Floristic, vegetation, and physical environmental datawere collected from 18 XLPs in Kentucky and used in conjunction with data collected inother studies to provide a synthesis for XLP vegetation in eastern United States and acomparison of this vegetation type with limestone cedar glades and deep-soil barrens.XLPs occur on 33 soil series in five orders (Alfisols, Mollisols, Ultisols, Inceptisols, andVertisols) and on limestone, dolomite, and calcareous shale of Cambrian through Tertiarysystems. In Kentucky, XLPs are restricted to the Interior Low Plateaus, where they aremost frequent on the Upper Mississippian Salem Limestone in the KnobstoneEscarpment and Knobs. Three hundred and thirty-five taxa were recorded in the 18 sitessampled in Kentucky, of which 20 (6.0%) are nonnative and 24 (7.2%) state-listed asrare. The majority of the flora is intraneous C3 hemicryptophytes. Thirteen taxa areendemic to XLPs of eastern United States, but none to those in Kentucky. The native, C4perennial grass Schizachyrium scoparium was dominant in 10 of 12 community types inKentucky identified at a scale of 100-m2 and in 21 of 23 studies of XLPs in easternUnited States. The C4 annual grass Sporobolus vaginiflorus had high frequency values inthe majority of sites in Kentucky, where it often was dominant in the most shallow-soilzones. Variability among XLPs in Kentucky and among the floras of XLPs in differentregions is largely attributable to differences in forb species composition. Soil depth is theprimary abiotic source of variability in XLP community types in Kentucky and in manyother regions of eastern United States. Dendrochronological and aerial photographicstudies support the conclusion that the vast majority of XLPs are not primarycommunities. XLPs on the Cambrian Ketona Dolomite in the Ridge and Valley in BibbCounty, Alabama, are perhaps the only sites which represent an edaphic climax.
5

Evaluating The Impacts Of Southern Pine Beetle On Pitch Pine Forest Dynamics In A Newly Invaded Region

Heuss, Molly 01 January 2018 (has links)
Southern pine beetle (SPB; Dendroctonus frontalis Zimmerman), a native insect that has historically affected pine ecosystems in the southeastern U.S., has recently expanded northward causing extensive tree mortality in pitch pine (Pinus rigida) and pitch pine-oak (Quercus spp.) forests across much of eastern Long Island, NY. Given the historic lack of SPB within these fire-dependent ecosystems, little is known regarding its impacts to forest composition, forest structure, or fuel loading. This study examined the short-term effects of SPB-induced tree mortality on the structure, composition, and fuel loading of pitch pine and pitch pine-oak communities to inform management recommendations and projections of future forest conditions and fire hazard. Overstory pine basal area declined following SPB infestation and infestation suppression management, particularly in pitch pine forests. These treatments did not impact the density or composition of seedlings and saplings, with hardwood species, including scarlet oak (Quercus coccinea), scrub oak (Quercus ilicifolia), and black gum (Nyssa sylvatica), making up the majority of species in this layer and pine representing <6% of stems. Likelihood of herbivory was influenced partly by species, with pitch pine less likely to be browsed than white oak and scarlet oak. SPB infestation significantly increased the snag component of both forest types, which largely became downed coarse woody debris (CWD) following suppression management. Treatments did not significantly influence understory species assemblages. Understory communities in pitch pine stands were characterized by Vaccinium angustifolium prior to SPB or suppression management, with these disturbances leading to an increase in the diversity of understory communities. In contrast, infestation decreased variation in understory species assemblages in pine-oak forests and encouraged regeneration of pitch pine and scarlet oak, while suppression increased diversity largely through increases in disturbance-adapted species, such as Smilax rotundifolia. SPB infestation decreased the biomass of live fuels and subsequently increased loading of dead fuels in both forest cover types. Suppression management felled preexisting and SPB-generated snags, especially in pitch pine forests, transforming vertical fuels into horizontal CWD. Collectively, results indicate SPB could functionally eliminate pitch pine without additional management intervention to maintain this species. Suppression efforts to reduce SPB impacts may accelerate succession towards hardwood dominance, particularly in pine-oak stand, leading to dramatic shifts in forest conditions across the Long Island Pine Barrens. SPB and suppression management significantly increase dead fuel loading and felling of snags during suppression served to decrease the density of ladder fuels effectively decreasing the risk of crowning. However, heavy CWD loading may also promote volatile fire behavior. Therefore, forest managers must weigh the expected potential impacts of SPB relative to changes to fuel structure and composition generated by suppression management activities. Our results demonstrate short-term effects of SPB and suppression management. Given the limited experience with SPB in these forests and the results of this study, further research on fire behavior effects and patterns of stand development over the long-term are needed.
6

Ecosystems as Models for Plant Selection on Extensive Green Roofs in Southern Ontario

Natvik, Mathis 11 May 2012 (has links)
Research on green roofs has shown their potential to moderate stormwater runoff and excessive heat in large cities. This has supported the implementation of a bylaw in Toronto, Canada which mandates large scale green roof construction. However, designers lack knowledge on appropriate plant selection for local green roofs. European research has demonstrated that healthy plant cover can significantly improve stormwater capture and cooling on green roofs. This thesis employed two methodologies to select native plants suitable for green roofs. Plants species were first identified from Ontario ecosystems with conditions similar to extensive green roofs including alvars, rock barrens, talus and cliffs. Secondly, plant surveys of existing extensive green roofs in Toronto and other southern Ontario locations to discover plant species already in use. Formal testing of the plant species generated from both methodologies can eventually provide designers with knowledge of dependable plant assemblages for extensive green roofs in Toronto.
7

A Rhetorical Analysis of Strategic Communication in the Amalga Barrens Wetlands Controversy

Vernon, Laura 01 August 2013 (has links)
This study is a rhetorical analysis of strategic communication in the Amalga Barrens wetlands controversy during the 1990s. The Bridgerland Audubon Society (BAS) in Cache Valley, Utah, was able to influence a change in public policy that removed the unique wetlands from consideration as a possible reservoir site for water taken from the Bear River. BAS led a successful grassroots effort by being civil, targeting specific individuals who had influence with the Utah legislature, focusing less on the environment and more on cost arguments that mattered to decision-makers, creating a portfolio of arguments grounded in scientific and economic data, and educating the community. BAS’s experience may be helpful to other environmental groups that are trying to lead efforts in their own communities. Although the strategies presented cannot be generalized to fit all groups and situations, they may serve as a starting point.
8

Modelling the fill-and-spill dynamics and wildfire impacts on the hydrological connectivity of ephemeral wetlands in a rock barrens landscape

Verkaik, Gregory January 2021 (has links)
Ontario’s rock barrens landscape consists of exposed bedrock ridges which host a mosaic of thin lichen- and moss- covered soil patches, forested valleys, beaver ponds, and depressional wetlands. Peat-filled ephemeral wetlands within bedrock depressions act as gatekeepers to hydrological connectivity between their small headwater catchments and the rest of the landscape downstream through strong fill-and-spill dynamics. We developed a water balance model, RHO, with inputs of precipitation and potential evapotranspiration (PET) to better understand the factors impacting water table (WT) and storage dynamics and in turn the hydrological connectivity of ephemeral wetlands. Field surveys were conducted at six wetlands to obtain and determine the variability in measurable site characteristics, in particular the wetland depression morphometry, to parameterize RHO. Three sites were used in a calibration and validation procedure where modelled WTs were compared to measured WT data from the snow-free seasons for each site to determine the best parameter values. We show that RHO is capable of predicting WT dynamics with inputs of precipitation and PET, when parameterized for specific sites. Wildfire disturbance is known to increase the run-off from hillslopes and remove surface organic soils through combustion. To predict the impacts of wildfire disturbance on ephemeral wetland hydrological connectivity, a generic model wetland depression was parameterized in RHO and used to predict the changes in hydrological connectivity under various wildfire scenarios and test the sensitivity of modelled connectedness to impacted parameters. Modelled results show that connectivity increases under all scenarios tested, and that changes to connectivity are primarily due to increases in run-in. Water balance models, like RHO, can be used to better understand the hydrological connectivity of wetlands in a rock barrens landscape. These models are useful in predicting impacts on the hydrological connectivity, and hydrological ecosystem services, from disturbances such as wildfire and can inform future field research experimental designs. / Thesis / Master of Science (MSc) / Rock barrens landscapes provide several important ecosystem services, which are influenced by hydrological flow paths and water storage on the landscape. Central to these hydrological dynamics is the storage and discharge of water in small wetlands which form in bedrock depressions. Here we develop a simple hydrological model to simulate the water storage and discharge of rock barrens wetlands. We then use this model to explore how wildfire disturbance is likely to change the supply of water to the rest of the landscape by simulating several different scenarios and testing which changes in the model have the largest impact on the water supply. We show that wetlands discharge more water after wildfire disturbance, mainly because of increases in run-off from areas upstream of the impacted wetlands. This modelling approach helps us better understand how wildfire is likely to impact the ecosystem services of a rock barrens landscapes.
9

Ecohydrological controls of natural and restored lichen and moss CO2 exchange on a rock barrens landscape

Hudson, Danielle January 2020 (has links)
Lichen and moss are the dominant ground cover on the Canadian Shield rock barrens of eastern Georgian Bay, and they provide many ecosystem services. Lichen and moss mats are essential for developing and accumulating soil on the bedrock landscape, and as the mats establish they moderate soil temperature and reduce soil water losses, thereby improving the microclimate for more complex vegetation. In addition to pioneering ecosystem succession, the lichen and moss mats provide essential nesting habitat for turtle species-at-risk. These lichen and moss mats are not well understood on rock barrens landscapes, and as such this thesis aims to increase knowledge of the growth, persistence and restoration approaches for these valuable ecosystem resources. We quantified the ecohydrological controls on the growth of lichen and moss mats by measuring the CO2 exchange of lichen and moss under varying environmental conditions. From these results we determined that key growth periods for lichen and moss were during the wet portions of the growing season (spring and fall), and that growth was limited or non-existent during the dry period (summer). Further, we determined that soil moisture was the most important control on lichen and moss CO2 exchange, and that this relationship differed among cover type (lichen, moss, mix of lichen and moss). Moss was able to continue CO2 uptake at a lower water content than lichen, suggesting that lichen would have a greater decline in productivity under drier conditions. A decline in lichen and moss productivity would also likely lead to a decline in soil development through chemical weathering which, in turn, could affect the availability of turtle nesting habitat. We also used CO2 exchange measurements to compare lichen and moss productivity between natural and transplanted mats. Transplanting in-tact patches of lichen and moss has not been widely studied, and as such we tested this approach on a rock barrens landscape. We determined that natural and transplant productivity did not differ for lichen, and that there were some differences between treatments for mixed and moss plots. We also used the tea bag index method to compare relative decomposition rates between treatments (natural, transplant), where we found that decomposition rates did not differ. Our results indicate that it is feasible to remove lichen mats from the footprint of a planned disturbance such as construction and transplant them successfully to nearby undisturbed areas. This approach would restore the lichen cover and the ecosystem services that lichens provide immediately rather than waiting decades for natural regrowth or fragment establishment. As a whole, this thesis will increase knowledge of both the growth and persistence, as well as the restoration of lichen and moss on rock barrens landscapes. Given that lichens and mosses of these genera grow globally, our findings can be applied widely to enhance and protect lichen and moss mats, and the ecosystem services they provide / Thesis / Master of Science (MSc)
10

Spatial Pattern Analysis of Tree Species Distribution in a Central Appalachian Upland Heath Barren

Goeke Dee, Gretchen Elise 26 August 2020 (has links)
The spatial pattern of plants reflects biotic and abiotic factors, including interactions with surrounding environmental conditions and other plants. Appalachian heath systems are presently understudied regarding spatial point pattern research, despite representing a unique and biologically valuable ecosystem. In this study, we characterized the spatial pattern of three tree species distributions in the upland heath barrens on Cabin Mountain in Canaan Valley, West Virginia through fieldwork, statistical modeling, and the use of geographical information systems (GIS). The research objectives were to: 1) quantify the global and local spatial patterns of trees to infer biotic process, and 2) identify how tree spatial pattern varies with selected biophysical variables, including ground curvature and topographic wetness index, to understand potential relationships between ambient conditions and spatial pattern. The spatial statistics, Ripley's K-function and nearest neighbor analysis, presented a series of different interaction types reflected across size-growth classes and species where the null hypothesis was rejected for some pairs and supported in others. The selected biophysical variables had no significant relationship to spatial pattern at the site. These findings suggest a range of both intraspecific and interspecific interactions are taking place in the heath barrens of Cabin Mountain, where significant levels of facilitation are occurring among encroaching red maple and striped maple, while red spruce is in competition with both species of maple, and that relationships are formed outside the influence of topographic characteristics of the site. / Master of Science / The spatial pattern of plants reflects biotic and abiotic factors, including interactions with surrounding environmental conditions and other plants. Appalachian heath barrens are presently understudied in regard to spatial point pattern research, despite representing a unique and biologically valuable ecosystem. In this study, we characterized the spatial pattern of three tree species in the red spruce heath barrens on Cabin Mountain in Canaan Valley, West Virginia through fieldwork, statistical modeling, and the use of geographical information systems (GIS). The research objectives were to: 1) quantify demographics and the spatial pattern of trees to assess for ongoing plant interaction, and 2) understand whether tree spatial pattern is affected by selected biophysical variables, including ground curvature and topographic wetness index, to understand potential relationships between environmental conditions and spatial pattern. The results suggested a range of interactions were occurring across the plot, intraspecies, different species-pairs, and size-growth classes. Most notably, encroaching striped and red maple species, had a positive relationship, while red spruce and both maple species had largely competitive relationships. Both topographic wetness index and ground curvature had no significant relationship to spatial pattern at the site. These findings suggest a range of both intraspecific and interspecific interactions are taking place in the heath barrens of Cabin Mountain, indicating the possibility of conversion from red spruce heath barrens to deciduous forest, that this pattern is formed outside the influence of topographic characteristics of the site.

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