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Full-Text Articles in Environmental Sciences

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 Dec 2023

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 …


Multidimensional Investigation Of Tennessee’S Urban Forest, Jillian L. Gorrell May 2023

Multidimensional Investigation Of Tennessee’S Urban Forest, Jillian L. Gorrell

Doctoral Dissertations

Preserving existing trees in urban areas and properly cultivating urban forest conservation and management opportunities is valuable to the ever-growing urban environment and necessary for creating optimal experiences and educational tools to meet the needs of increasing urban populations. This dissertation contains studies investigating several facets of the urban forest, including environmental effects of deforestation and urbanization, tree equity, and urban forest facility management and accessibility. Community education and outreach at arboreta about the importance of the tree canopy can help promote environmental stewardship. A digital questionnaire was electronically distributed to representatives of arboreta certified through the Tennessee Division of …


Association Between Stream Impairment By Mercury And Superfund Sites In The Conterminous Usa, Karessa L. Manning May 2021

Association Between Stream Impairment By Mercury And Superfund Sites In The Conterminous Usa, Karessa L. Manning

Masters Theses

Mercury is a natural element that can cause harm to the brain, heart, kidneys, lungs, and immune system, especially to fetuses developing in the womb. Many natural and anthropogenic factors contribute to mercury in the environment, such as geologic deposits, landfills, gold and silver mining operations, cement production, and atmospheric deposition. Mercury has been identified as a contaminant of concern at many National Priority List (NPL) sites, however, studies on contamination at NPL sites are often only conducted on a local level. This study was to analyze the potential connection between mercury-contaminated NPL sites and the presence of mercury impaired …


Ecosystem Services Of Urban Tree Canopy For The Mitigation Of Climate Change: Measuring Carbon Sequestration And Understory Temperature Reduction Of Knoxville’S Urban Forest, Tyler Hounshell May 2020

Ecosystem Services Of Urban Tree Canopy For The Mitigation Of Climate Change: Measuring Carbon Sequestration And Understory Temperature Reduction Of Knoxville’S Urban Forest, Tyler Hounshell

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

In the future, the city of Knoxville, Tennessee will be impacted by climate warming due to anthropogenic climate change. Yet, the ecosystem services provided by urban tree canopy in Knoxville’s urban forest can help mitigate the effects of climate warming. In addition to improving air quality, regulating water flow, and reducing noise pollution, Knoxville’s urban forest serves as a carbon sink and sequesters carbon dioxide on an annual basis. Utilizing methods for calculating carbon sequestration by trees in urban and suburban settings developed by the U.S. Energy Information Administration, the sequestration potential and its uncertainty is calculated until the year …


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. Jun 2018

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 …


Hypericum Irazuense Kuntze Ex N. Robson In The Buenavista And Chirripó Páramos Of Costa Rica: Photographs Of Stem Cross Sections, Plants, And Study Sites, Sally P Horn, Matthew T. Kerr May 2017

Hypericum Irazuense Kuntze Ex N. Robson In The Buenavista And Chirripó Páramos Of Costa Rica: Photographs Of Stem Cross Sections, Plants, And Study Sites, Sally P Horn, Matthew T. Kerr

Geography Publications and Other Works

Hypericum irazuense Kuntze ex N. Robson is a common shrub in the high-elevation páramos that occur above treeline on the high peaks of the Cordillera de Talamanca in Costa Rica and westernmost Panama. In this report and accompanying high-resolution images we make available photographs of stem cross sections, plants, and habitats of H. irazuense in support of a recent study of the dendrochronological potential of the species (Kerr et al., forthcoming paper in Physical Geography) and other research on this plant and the páramo vegetation in which it occurs. We also include images from the Google EarthTM map …


Effects Of Switchgrass Related Land-Use Changes On Aquatic Macroinvertebrates, Latha Malar Baskaran May 2017

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 …


Modelling Cash Crop Growth In Tn, Spencer Weston May 2017

Modelling Cash Crop Growth In Tn, Spencer Weston

Chancellor’s Honors Program Projects

No abstract provided.


Fire History Of The Appalachian Region: A Review And Synthesis, Charles W. Lafon, Adam T. Naito, Henri D. Grissino-Mayer, Sally P Horn, Thomas A. Waldrop Jan 2017

Fire History Of The Appalachian Region: A Review And Synthesis, Charles W. Lafon, Adam T. Naito, Henri D. Grissino-Mayer, Sally P Horn, Thomas A. Waldrop

Geography Publications and Other Works

The importance of fire in shaping Appalachian vegetation has become increasingly apparent over the last 25 years. This period has seen declines in oak (Quercus) and pine (Pinus) forests and other fire-dependent ecosystems, which in the near-exclusion of fire are being replaced by fire-sensitive mesophytic vegetation. These vegetation changes imply that Appalachian vegetation had developed under a history of burning before the fire-exclusion era, a possibility that has motivated investigations of Appalachian fire history using proxy evidence. Here we synthesize those investigations to obtain an up-to-date portrayal of Appalachian fire history. We organize the report by …


Incendios En Los Pinares De Las Zonas Montañosas De La República Dominicana: La Visión De Fondo, Sally P Horn Oct 2016

Incendios En Los Pinares De Las Zonas Montañosas De La República Dominicana: La Visión De Fondo, Sally P Horn

Geography Publications and Other Works

Fire in Highland Pine Forests of the Dominican Republic―The Long View

Large forest fires in Valle Nuevo National Park in 2014 and 2015 have increased interest in fire as an ecological force in montane pine forests of the Dominican Republic. Geographer Dr. José Ramón Martínez Batlle estimated using Landsat imagery and GIS that some 4700 ha burned in July 2014 (http://www.geografiafisica.org/2014/07/29/superficie-quemada-incendio-valle-nuevo/), and an additional 1600 ha burned in late April 2015 (http://www.geografiafisica.org/2015/09/25/superficie-quemada-en-valle-nuevo-finales-de-abril-principios-de-mayo-2015/).

Since 1995, when I first visited what is today Valle Nuevo National Park (then, Valle Nuevo Scientific Reserve), as a guest of the Moscoso …


Impacts Of Climate Change On The Evolution Of The Electrical Grid, Melissa Ree Allen Aug 2014

Impacts Of Climate Change On The Evolution Of The Electrical Grid, Melissa Ree Allen

Doctoral Dissertations

Maintaining interdependent infrastructures exposed to a changing climate requires understanding 1) the local impact on power assets; 2) how the infrastructure will evolve as the demand for infrastructure changes location and volume and; 3) what vulnerabilities are introduced by these changing infrastructure topologies. This dissertation attempts to develop a methodology that will a) downscale the climate direct effect on the infrastructure; b) allow population to redistribute in response to increasing extreme events that will increase under climate impacts; and c) project new distributions of electricity demand in the mid-21st century.

The research was structured in three parts. The first …


A Multidimensional Analysis Of The Great Green Wall: The Environmental And Social Effects Of Reafforestation In Senegal, Anna Eugenia Alsobrook May 2014

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 …


Public Land In A Changing Climate: Planning For An Uncertain Future, Kathleen Marie Hauser Dec 2012

Public Land In A Changing Climate: Planning For An Uncertain Future, Kathleen Marie Hauser

Masters Theses

This thesis investigates the ways in which institutions and actors consider climate change, and how the inclusion of diverse perspectives and challenges in the planning process shapes climate change governance. In particular, I asked how the participants, place-specific contexts, and decision-making processes affect environmental decision-making in Alaska’s National Parks. I discuss the literature on geographical perspectives on climate change, environmental and climate change governance, how uncertainty and risk affect decision-making in the context of climate change, and the history of land use management in the United States. This project incorporates qualitative methods to research the Climate Change Scenario Planning project …


Spatial Discrepancies Between Nhdplus And Lidar-Derived Stream Networks, Nicole Marie Samu May 2012

Spatial Discrepancies Between Nhdplus And Lidar-Derived Stream Networks, Nicole Marie Samu

Masters Theses

Many organizations demand that current water resource issues necessitate improved stream network mapping for more accurate and reliable watershed analysis and modeling results, which can ultimately enable better management and policy decisions. Stream network data from the National Hydrography Dataset Plus (NHDPlus) and derived from Light Detection and Ranging (LIDAR) are each widely accepted to be of superior quality compared to many other conventional datasets. Each dataset indicates potential to improve a wide range of water resource applications; NHDPlus for its high spatial accuracy and functionality, and LIDAR-derived networks for their high resolutions. NHDPlus is publicly available and widely used; …


The Effects Of Land-Use Change On The Hydrological Properties Of Andisols In The Ecuadorian Paramo, James Joseph Hartsig May 2011

The Effects Of Land-Use Change On The Hydrological Properties Of Andisols In The Ecuadorian Paramo, James Joseph Hartsig

Masters Theses

The Ecuadorian páramo is characterized by unique soil properties that allow the ground to hold large amounts of water. These páramo grasslands support Andean cities and communities as a source of water for municipal, industrial, and agricultural use. Although recent research has suggested that changes in land use can decrease the amount of water and affect the water-holding capabilities of the soil, the hydrologic effects of different land uses, including burning for livestock grazing and pine planting for carbon credits, are currently under debate.

This research tested hypotheses about moisture-related properties of páramo soils under different land uses at two …


A Vegetation History From Emerald Pond, Great Abaco Island, The Bahamas, Based On Pollen Analysis, Ian Arthur Slayton Aug 2010

A Vegetation History From Emerald Pond, Great Abaco Island, The Bahamas, Based On Pollen Analysis, Ian Arthur Slayton

Masters Theses

Emerald Pond (26° 32' 12" N, 77° 06' 32" W) is a vertical-walled solution hole in the pine rocklands of Great Abaco Island, The Bahamas. In 2006, Sally Horn, Ken Orvis, and students recovered an 8.7 m-long sediment core from the center of the pond using a Colinvaux-Vohnout locking piston corer. AMS radiocarbon dates on macrofossils are in stratigraphic order and indicate that the sequence extends to ca. 8400 cal yr BP. Basal deposits consist of aeolian sands topped by a soil and then pond sediment, suggesting that the site began as a sheltered, dry hole during a Late Pleistocene …


Limnología De Las Lagunas Glaciales En El Páramo Del Chirripó, Costa Rica. (Limnology Of Glacial Lakes In The Chirripó Páramo Of Costa Rica.), Sally P Horn, Kenneth H. Orvis, Kurt A. Haberyan Jan 2005

Limnología De Las Lagunas Glaciales En El Páramo Del Chirripó, Costa Rica. (Limnology Of Glacial Lakes In The Chirripó Páramo Of Costa Rica.), Sally P Horn, Kenneth H. Orvis, Kurt A. Haberyan

Geography Publications and Other Works

More than 30 lakes of glacial origin exist within the Chirripó páramo in the Cordillera de Talamanca of Costa Rica. This chapter describes the geomorphic setting and physical and chemical limnology of 19 lakes located between 3450-3570 m elevation in the upper basins of five glaciated valleys. All lakes are clear, dilute, and apparently polymictic. Water chemistry data from 1998, 2000, and 2001 are similar from lake to lake and year to year, and are consistent with sparse prior measurements between 1966 and 1991. However, the lake water temperatures we have measured are much higher than those reported by earlier …


Registros De Sedimentos Lacustres De La Vegetación Del Holoceno Y Historia Del Fuego En El Páramo De Costa Rica. (Lake-Sediment Records Of Holocene Vegetation And Fire History In The Costa Rican Páramos), Sally P Horn, Brandon L. League Jan 2005

Registros De Sedimentos Lacustres De La Vegetación Del Holoceno Y Historia Del Fuego En El Páramo De Costa Rica. (Lake-Sediment Records Of Holocene Vegetation And Fire History In The Costa Rican Páramos), Sally P Horn, Brandon L. League

Geography Publications and Other Works

We examined pollen, pteridophyte (ferns and fern-allies) spores, and charcoal in a 5.6 m long sediment core from Lago de las Morrenas 1, and charcoal in a 1.1 m long sediment core from Lago Chirripó, to reconstruct postglacial vegetation and fire history in the Chirripó páramo. Lago de las Morrenas 1, the largest lake in the Valle de las Morrenas of Chirripó National Park, is presently surrounded by treeless páramo vegetation and has apparently been so since deglaciation approximately 10,000 radiocarbon years ago. Pollen spectra suggest no pronounced changes in vegetation since ice retreat. Pollen percentages for Gramineae and other …