Physical and Environmental Geography Commons^™

Initial Limnology Of Laguna Pozo Verde, Costa Rica: Bathymetry, Water, Sediments, And Diatoms, Sally P Horn, Erik N. Johanson, Mauricio Murillo Herrera, Kurt A. Haberyan, Taber Friedel, Chad S. Lane

Geography Publications and Other Works

ABSTRACT. Introduction: Costa Rica has hundreds of lakes, many of which have never been scientifically studied. Objective: To carry out a first, basic limnological study of Laguna Pozo Verde in Juan Castro Blanco National Park, Costa Rica (~1935m elevation), to provide baseline data for studying future changes. Methods: We measured water depths and temperatures, and Secchi depth; analyzed surface sediments; and examined maps and satellite imagery. Results: Though described by some as formed by volcanic processes, Laguna Pozo Verde likely formed in a landslide, which occur frequently in this rainy area on the steep south slope of the inactive Porvenir …

Climatological Analysis Of Tropical Cyclone Occurrence Dates And Landfall Characteristics In The North Atlantic And Eastern North Pacific, Nicholas Sava Grondin

Doctoral Dissertations

Tropical cyclones (TCs) are significant hazards to coastal and inland regions across the globe, especially in North America. North America is affected by TCs from two basins, the North Atlantic (NATL) and eastern North Pacific (ENP), with the former being the predominate focus of past research. In this dissertation, I present three studies that directly compare TCs in the NATL and ENP by using the same methods for each basin in studying occurrence dates and intraseasonal variability, effects of environmental parameters on occurrence dates and seasonal forecasting, and the behavior of TCs during the final 36 hours before landfall in …

Nashville-Basin Tornadoes: Using Storm Types To Elucidate The Local Climatology And Forecasting Challenges, Morgan Steckler, Kelsey Ellis

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

Early 3 March 2020 was a devastating night for many middle Tennessee residents. A strong EF-3 tornado tore through Nashville at 65 mph, and another EF-4 killed 18 in Baxter and Cookeville alone. Residents of the Southeastern United States are particularly vulnerable to tornadoes. This study aims to better understand local forecasting challenges by looking at the types of storms that produce tornadoes. Storm types, also known as convective modes, divide tornado-producing storms into categories by length, shape, multiplicity, and intensity. Distinguishing storms by these modes allows for a broader understanding of their occurrences and impacts. This study specifically evaluates …

Statistical And Spatial Analysis Of Hurricane-Induced Power Outage And Restoration, Dakotah Daniel Maguire

Masters Theses

Tropical cyclones (TC) cause billions of dollars in damage to coastal areas in the United States annually. Global climate change is increasing favorable environmental conditions for TCs which produce heavy flooding and precipitation. It is important to understand the communities that will be most affected, and will likely suffer the longest power outages. County-level power outage data from the Department of Energy’s Environment for Analysis of Geo-Located Energy Information (EAGLE-I) were used to analyze the relationships of environmental and socioeconomic variables on power outage trends, response, and recovery for power outages caused by two North Atlantic Basin hurricanes: Hurricane Florence …

Landslide Mapping And Susceptibility Assessment Of Chittagong Hilly Areas, Bangladesh, Yasin Wahid Rabby

Doctoral Dissertations

Landslides are natural phenomena in mountainous areas that cause damage to properties and death to people around the world. In Bangladesh, landslides have caused enormous economic loss and casualty in Chittagong Hilly Areas (CHA). In this dissertation, a landslide inventory of CHA was prepared using Google Earth and field mapping. Google Earth-based mapping helped in recording landslides in inaccessible areas like forests. In contrast, field mapping helped in mapping landslides in accessible areas like areas near road networks. For absence data sampling of landslide susceptibility mapping, this research proposed the Mahalanobis distance (MD) based absence data sampling and compared it …

Hazardous Weather And Human Response In The Southeastern United States, Daniel Burow

Doctoral Dissertations

Effectively mitigating the human costs of future hazardous weather events requires examining meteorological threats, their long-term patterns, and human response to these events. The southeastern United States is a region that has both a high climatological risk and a high societal vulnerability to many different meteorological hazards. In this dissertation, I study hazardous weather and human response in the Southeast through three different lenses: identifying uniquely simultaneous hazards posed by tropical cyclones, assessing precipitation and synoptic weather patterns on hazardous weather days, and examining patterns in intended response to tornado watches. I find that simultaneous and collocated tornado and flash …

Tweet Diffusion Over Space And Time: A Comparison Of A Winter-Weather And Tornado-Outbreak Case Study, Alyssa Margaret Cannistraci

Masters Theses

Social media allows people to receive, engage in, and share weather information. Users of the social media platform Twitter actively share weather content via tweets, which researchers can acquire through an Application Programming Interface (API). APIs return tweet content, as well as temporal and spatial characteristics (latitude and longitude coordinates). Tweets can then be mapped and studied spatiotemporally through Geographic Information System (GIS) software. For this work, I compared how tweets spread (“diffuse”) over space and time during two natural hazard events in the United States. The first case study is a winter weather event that The Weather Channel named …

Identifying Smokestacks In Remotely Sensed Imagery Via Deep Learning Algorithms, Kenneth Moss

Masters Theses

Locating smokestacks in remote sensing imagery is a crucial first step to calculating smokestack heights, which allows for the accurate modeling of dioxin pollution spread and the study of resulting health impacts. In the interest of automating this process, this thesis examines deep learning networks and how changes in input datasets and network architecture affect image detection accuracy. This initial image detection serves as the first step in automated object recognition and height calculation. While this is applicable to general land use classification, this study specifically addresses detecting smokestack images. Different dataset scenarios are generated from the massive Functional Map …

Lidar-Based Sinkhole Detection And Mapping In Knox County, Tennessee, J Clint Shannon, David Moore, Yingkui Li, Cathy Olsen

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

Sinkholes are one of the major causes of damage to roads, buildings, and other infrastructure throughout the US. Sinkholes near or on roads are especially costly and occasionally deadly. Knox County and much of East Tennessee are located within karst areas (comprised of porous and soluble limestone and dolomite), deeming it at risk for sinkholes. Currently, Knox County uses contour maps to manually identify sinkholes. Supported by a geographic information system (GIS), we developed a streamlined model to identify the locations and extents of potential sinkholes using 1.3-ft resolution LiDAR (Light Detection and Ranging) data and applied it to the …

Mapping Glacial Landforms On The Chiripó Massif, Costa Rica, Based On Google Earth, A Digital Elevation Model, And Field Observations, Yingkui Li, Taylor Tieche, Sally P. Horn, Yanan Li, Renrong Chen, Kenneth H. Orvis

Geography Publications and Other Works

The Chirripó massif in the Cordillera de Talamanca, Costa Rica, is one of a few sites in Central America that preserve evidence of past glaciation. We mapped glacial landforms in this area using Google Earth high-resolution imagery and a 30 m Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM). Prior field observations, field notes, photographs, and landform maps were used to check and refine the delineated landform boundaries. The composited map includes lateral and terminal moraines, tills, glacial valleys, glacial lakes, nunataks, arêtes, and horns. Glacial extents during three proposed stages were mapped in the Valle de las Morrenas, …

Initial Limnological Observations At Five Small Lakes In Southern Pacific Costa Rica, Sally P Horn, Erik N. Johanson, Kurt A. Haberyan, Mathew S. Boehm, Jessie L. Johanson, Maureen Sánchez P., Mario Hernández V.

Geography Publications and Other Works

Costa Rica has hundreds of lakes, many of which have never been described or sampled by limnologists. Here we summarize initial observations of five small (0.2–1.7ha) lakes located at low elevation (365–490m) in the cantón of Buenos Aries. We collected basic limnological data and samples during visits in 2013 and 2014, and compiled environmental and archaeological data for their surroundings as a contribution to the documentation of lake diversity in Costa Rica, and to support parallel investigations of indicators of environmental history preserved in the sediments of the lakes. Lagunas Carse, Los Mangos, Danta, and Ojo de Agua all appear …

Effects Of Switchgrass Related Land-Use Changes On Aquatic Macroinvertebrates, Latha Malar Baskaran

Doctoral Dissertations

This research examines if switchgrass-based land-management practices have the potential to influence aquatic macroinvertebrates through changes in stream flow and water quality. The number of taxa in Ephemeroptera, Plecoptera, and Trichoptera orders (EPT taxa richness/EPT-TR) is analyzed as an aquatic macroinvertebrate bioindicator in the context of regional environmental effects, and changes in stream flow and water quality. This dissertation is structured as three manuscripts that link together to address the overall research question.

The first manuscript focuses on identifying regional environmental variables that influence EPT-TR across ecoregions in Tennessee. The influences of temperature, precipitation, geology, soil, stream flow and velocity …

Understanding The Vulnerability Of The Population Of Afghanistan Under Multiple Natural And Anthropogenic Risks With An Indicator-Based Analysis, Matthew Repine Miller

Masters Theses

The purpose of this study is to understand the vulnerability to natural and anthropogenic hazards of the population of Afghanistan and the social factors which enhance or moderate such vulnerability. While vulnerability studies are commonly conducted in the United States, as well as many other global north countries, most studies of this type utilize data collected by central government entities in the form of a census which is periodically executed and uses standardized collection methods. In the case of Afghanistan, and many other countries in the global south, such data is hard to acquire, lacks a high level of confidence, …

Reconstructing Late Holocene Fire, Agriculture, And Climate From Sediment Records In Costa Rica And The Dominican Republic, Erik Nicholas Johanson

Doctoral Dissertations

We use multiple proxies from sediment cores to identify periods of climate stress during the late Holocene across the circum-Caribbean region and to determine how fire activity and signals of Pre-Columbian agriculture coincide with these arid periods. We examine evidence of aridity from stable carbon isotope ratios and shifts in elemental composition, along with pollen and microscopic charcoal, at Bao Bog in the highlands of Hispaniola. We infer two major periods of aridity (3600–2300 and 1040–850 cal yr BP), with the later period associated with the late phase of the Terminal Classic Drought. A third, less marked interval of aridity …

Using Spatial Analysis To Evaluate Fire Activity In A Pine Rockland Ecosystem, Big Pine Key, Florida, Usa, Lauren Ashley Stachowiak

Doctoral Dissertations

Pine rocklands are fire-prone ecosystems with limited spatial extent, and have experienced reduced area in the previous decades through habitat conversion and urbanization. The purpose of this dissertation research was to evaluate the historical range of variability of fire activity and spatial patterns of fires in a pine rockland ecosystem in the National Key Deer Refuge (NKDR) on Big Pine Key in the Lower Florida Keys. To investigate the temporal and spatial patterns in fire activity, I (1) evaluated the temporal patterns for fires in my study area in the NKDR, (2) analyzed differences in standard fire history metrics since …

Establishing A Chronology Of Late Quaternary Glacial Advances In The Cordillera De Talamanca, Costa Rica, Rebecca Susan Potter

Masters Theses

Little research has focused on glacial events in the tropics. Providing an absolute glacial chronology in Costa Rica will build a foundation for future glacial chronologies and paleoclimate reconstructions in the highlands of Central America. Evidence of past glaciation, including moraines and glacial lakes, is preserved within formerly glaciated valleys in the Cordillera de Talamanca. Orvis and Horn (2000) constrained deglaciation ages of the most recent glacial event in the Cordillera de Talamanca based on radiocarbon dates of glacial lake sediments. Radiocarbon ages indicated complete deglaciation after 12.4 ka cal BP but before 9.7 ka cal BP (Orvis and Horn, …

Linking Soil Moisture And Carbon-Cycle Processes In Two Understudied Terrestrial Ecosystems: Ecuadorian Páramo Grasslands And Constructed Agricultural Wetlands, Julie Yvette Mcknight

Doctoral Dissertations

A better understanding of soil-water interactions and associated feedbacks in carbon-cycle processes is necessary for addressing knowledge gaps in the global carbon budget. This doctoral dissertation research investigated soil carbon-cycle processes in two ecosystems, Ecuadorian páramos and constructed agricultural wetlands, which are understudied in terrestrial carbon research. These sites represent ecosystems where land-use induced changes in soil moisture were expected to play an important role in soil carbon processes.

Soil carbon dioxide (CO₂) flux and extracellular enzyme (EE) activities were measured to assess changes in soil carbon processes in soil from four types of land use in Ecuadorian …

A Decade Of Lessons Learned: The Local Implementation Of Stormwater Programs In Tennessee, Catherine Trudy Olsen

Masters Theses

Over the past decade, communities across the nation have innovated, regulated, and constructed their way to managing urban stormwater runoff, with the grand goal of making the nation’s waters fishable and swimmable. Regulated under federal NPDES MS4 Phase II stormwater permits, communities have endeavored to implement the comprehensive requirements of this unfunded federal mandate. Reducing the considerable impact of municipal runoff on water resources across the country is imperative to the achievement of grand goals under the Clean Water Act: to restore and protect the quality of the nation’s waters (USEPA, 2000). Across the state of Tennessee, the capacity of …

Stand Dynamics Of A Unique Pygmy Forest, El Malpais National Monument, New Mexico, U.S.A, Sarah Jones Wayman

Masters Theses

The pygmy forest is a rare ecosystem found on the 3000-year-old McCarty’s basalt flow in El Malpais National Monument, New Mexico. The forest is dominated by contorted, shortstatured forms of ponderosa pine (Pinus ponderosa Douglas ex C. Lawson) and piñyon pine (Pinus edulis Engelm.). The purpose of this research was to investigate the history of this unique forest and attempt to isolate reasons why the trees grow in such peculiar forms. We first used tree-ring patterns from 32 ponderosa pines growing on a sandstone kipuka located within the McCarty’s flow as a proxy for past precipitation, and used …

Time Series Analysis Of Modis Ndvi Data With Cloudy Pixels: Frequency-Domain And Sizer Analyses Of Vegetation Change In Western Rwanda, Ephraim Robert Love

Masters Theses

Remote sensing is a valuable source of data for the study of human ecology in rural areas. In this thesis, I attempt to analyze the presence of a long-term trend indicative of post-resettlement adaptation in the vegetation signals of Western Rwanda. There is a dearth of research utilizing medium resolution imagery to study difficult environments, such as tropical-montane regions, where complex topography and cloud cover diminish image accuracy. I attempt to add to the extant literature on frequency-domain smoothing methods as well as the literature on human-environment interaction in tropical-montane regions by applying a harmonic filtering and smoothing algorithm to …

Using Gis To Identify At-Risk Populations Of Military-Generated Dust, Darcy Ann Ayers

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

This project uses GIS and an anthropological perspective to identify local populations surrounding Pohakuloa Training Area (PTA) that are most at risk from military vehicle-generated dust. Using ArcGIS, the following data was analyzed in order to better understand impacts from dust on the local population: • Prevailing wind rose data from National Water and Climate Center under the USDA National Resources Conservation Service, • Digital Elevation Model (DEM) map of the island provided by National Elevation Dataset from USGS, and • The US Census data of the local population distribution surrounding the military base at PTA. When studying demographics, I …

Dendrogeomorphic Analysis Of Debris Slides On Mt. Le Conte, Great Smoky Mountains National Park, Tennessee, U.S.A., Maegen Lee Rochner

Masters Theses

Research conducted during the past 30 years tested the use of tree rings to date mass movement events in the mountain areas of Europe and the western and southwestern United States, but few studies have been performed in the eastern U.S., where debris flows, landslides, and rock falls in the Appalachian Mountains pose a common threat to human life and property. One area of particular interest is Great Smoky Mountains National Park (GSMNP). For this study, I tested mature red spruce (Picea rubens Sarg.) trees located on or near a debris slide boundary on Mt. Le Conte (LC01) in …

Climate Drivers Of Wildfire Activity In The Magdalena Mountains Of New Mexico, U.S.A., Elizabeth Anne Schneider

Masters Theses

In recent years, crown fires have raged through mixed-conifer forests in the American Southwest that historically experienced frequent, low-severity wildfires. Land management agencies now wish to restore wildfires to their historical range of variability, but this requires information on fire regimes before Euro-American disturbance took place. We characterized the historical fire regime of a high elevation, mixed-conifer forest in the Magdalena Mountains, New Mexico. This research evaluated the different climate drivers, represented by the Palmer Drought Severity Index (PDSI), the El Niño-Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO), and the Atlantic Multidecadal Oscillation (AMO), that influence the occurrence of …

Block 271, Reviving An Industrial Artifact, Jared Thomas Pohl

Masters Theses

Vacant industrial sites are scattered throughout our cities all across the country. These sites, these remnants of industry, are occupied by a very interesting category of buildings. They are artifacts from an industrial era that served very unique and specific functions. These service buildings suffered programmatic failure and have lost their vitality. They have entered a form of hibernation, waiting for the post-industrial epoch to wake them up.

The building stock under investigation makes up a large portion of the city’s structures. Identifiable by their heroic scale, clean articulated lines and tendency to be vacant, these service buildings raise arguments …

A Multidimensional Analysis Of The Great Green Wall: The Environmental And Social Effects Of Reafforestation In Senegal, Anna Eugenia Alsobrook

Masters Theses

The north-central region of Senegal is home to the Great Green Wall (GGW)—a reafforestation project aimed at restoring decades–old, degraded land conditions by establishing tree belts and community gardens. Its presence on the ground has changed the local landscape and altered the social institutions governing the daily lives of the people it aims to protect.

My study is an in-progress assessment of the GGW towards its two major goals: 1) improving the lives of the people of the Sahel and increasing their capacity to adapt to climate change and drought, and 2) improving the state of the ecosystem and increasing …

Stable Isotope Analysis Of Lake Sediments From Laguna Santa Elena And Laguna Azul, Costa Rica, Matthew Timothy Kerr

Masters Theses

Lake sediments are increasingly important archives of human-environment interactions and paleoclimate in the neotropics. In Costa Rica, Anchukaitis and Horn (Palaeogeography, Palaeoclimatology, Palaeoecology 221: 35–54, 2005) established a land-use history for Laguna Santa Elena (8.9306 N, 82.9275 W, 1055 m elevation), a small lake in the Diquís archaeological region, based on pollen and charcoal analyses of a 7-meter sediment core. I carried out stable carbon and nitrogen isotope and loss-on-ignition analyses at higher resolution to extend the existing 2000-year record. The new geochemical data parallel major trends in botanical proxies but also reveal aspects of human and environmental dynamics …

Methods For The Study Of Soil Charcoal As An Indicator Of Fire And Forest History In The Appalachian Region, U.S.A., Sally P Horn, Christopher A. Underwood

Geography Publications and Other Works

Charcoal particles in soils and sediments of the Appalachian region provide evidence of long-term fire history relevant to resource management and to studies of paleoclimate, vegetation history, and the effects of prehistoric and historic humans on the environment. Charcoal records of fire history are of low resolution in comparison to dendrochronological records, but reach well beyond the oldest trees in most areas, providing evidence of fires thousands or tens of thousands of years ago. We focus here on fire history reconstruction from soil charcoal, which provides site-specific evidence of past fires and potentially forest composition. Charcoal > 2 mm may be …

Geographic And Socioeconomic Risk Factors For Sporadic Cryptosdporidiosis And E. Coli Infection In East Tennessee, Ingrid Elizabeth Luffman

Doctoral Dissertations

This research examines risk factors for sporadic cryptosporidiosis and Escherichia coli (E. coli) O157 infection in East Tennessee, using case-control and retrospective ecological approaches. Multiple models and approaches are used to identify risk factors for the two diseases, and to examine the effect of scale on risk for disease in the individual and in the population. Risk factors examined are animal density, land use, geology, surface water impairment, poverty rate and availability of private water supply. The research objectives are, first, to identify risk factors for E. coli O157 and cryptosporidiosis in East Tennessee by relating disease data …

Fire And Forest History From Soil Charcoal In Yellow Pine And Mixed Hardwood-Pine Forests In The Southern Appalachian Mountains, U.S.A., Christopher Aaron Underwood

Doctoral Dissertations

The Holocene history and ecological role of fire in forested ecosystems in the southern Appalachians is incompletely known. Determining how often and when fire has affected forest communities requires us to think about fire over time scales that extend beyond those of written fire records. This research is the first to specifically address the spatio-temporal patterns of forest fires in southern Appalachian xeric forests using radiocarbon dating of taxonomically identified soil charcoal as the primary proxy. Forty-eight soil cores were recovered in eight sites established for a companion study of dendrochronological evidence of fire history. The eight sites were located …

A Dendroecological Evaluation Of The Effects Of Coal Ash On Tree Growth, Kingston Fossil Plant, Harriman, Tennessee, U.S.A., Niki Ann Garland

Masters Theses

Tree growth is a function of many environmental variables, and it is possible to detect differences between natural and human-related factors on tree growth. Radial growth of trees in one year and in subsequent years that follow is influenced not only by climate and other overarching multi-year processes, but also by pulse disturbance events. On December 22, 2008, an embankment at an impoundment for wet storage of fly ash at the Kingston Fossil Plant, Harriman, Tennessee collapsed, releasing 4,434,400 cubic meters of coal ash into the Clinch and Emory Rivers, impacting aquatic life as well as terrestrial flora and fauna. …