Digital Commons Network^™

A Gis Assessment Of Ecoregion Representation In Chile's Existing And Proposed Integrated Network Of Protected Areas, Jessica Schutz

Graduate Student Theses, Dissertations, & Professional Papers

Chile's state designated protected areas are reported to show representation bias and to be unable to meet conservation goals. Private protected areas are considered an important tool to resolve these issues, which has led to support for increasing the role of private protected areas in Chile and creating an integrated public-private protected area network. But the validity of the capacity of private protected areas to fix Chile's state protected area network bias, and the advantage of creating an integrated protected area network, have not been assessed. This study uses the most recent data on Chile's state, private, and international protected …

Barriers To Facilitating An Existing Certified Nature Explore Outdoor Classroom, Shelley L. Easler

Walden Dissertations and Doctoral Studies

In response to social trends whereby children are spending less time outside, school administrators have developed certified Nature Explore Outdoor Classrooms (NEOCs) intentionally designed to support whole-child learning within a natural environment. Despite the documented benefits of nature-based education, the literature and NEOC sites report challenges in facilitating this type of space. The purpose of this study was to investigate what prevents teachers in a certified NEOC from facilitating student/teacher engagement with the natural outdoor environment. Kolb's, Piaget's, and Vygotsky's theories of constructivism served as the study's framework to explore the problem from the teachers' perspectives. A qualitative case study …

Cows And Plows: Science-Based Conservation For Grassland Songbirds In Agricultural Landscapes, Marisa K. Lipsey

Graduate Student Theses, Dissertations, & Professional Papers

Temperate grasslands are among earth’s most imperiled ecosystems. In North America, steep declines of endemic songbird populations indicate that grassland loss and degradation may be approaching critical levels. Grasslands are agricultural landscapes largely (~85%) under private ownership with little formal protection status. Remaining bird populations depend on grazing lands that have not been converted to cropland. We combine regional data from a hotspot for grassland bird diversity (northeast Montana, USA; 26,500-km2) with continental data spanning the northern Great Plains (1,000,000-km2) to evaluate how land use and management influence bird distribution and abundance. Regionally, habitat used by seven grassland specialists spanned …

A Model For Determining Drivers Of Phenology In Western United States Rangelands, Joseph R. St. Peter

Graduate Student Theses, Dissertations, & Professional Papers

Plant phenology has long been used as an indicator of climate. Recent changes in plant phenology are evidence of the influence of climate change. Modeling plant phenology has become an effective tool to understand the impacts of climate change. Using machine learning techniques I developed a modeling process for accurately predicting phenology across a diverse landscape. This model uses individual site data to set site specific climate thresholds for plant phenology. This model also identifies the limiting factors to vegetation phenology for rangelands in the western United States. NDVI remotely sensed data was used to quantify land surface phenology and …

Development Of Dual-Bacterial Culture For Benzene Degradation And Biofilm Formation, Aiyarucht Techajindamanee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Dual bacterial culture is the technique using the different characteristic of two bacteria for support the bacterial culture ability. This study developed the dual culture of benzene-degrading bacteria and biofilm-forming bacteria, and optimized the culture conditions promoting their benzene degradation and biofilm formation for increasing benzene-removal efficiency and bacterial stability in benzene treatment systems. Acinetobacter sp. B36 was a benzene-degrading and biofilm-forming bacterium isolated from petroleum wastewater. The bacterial biofilm was promoted by dual-culturing with Pseudomonas sp. BF6 isolated from the same source. The optimum culture conditions were studied focused on co-carbon source, nitrogen source, oxygen and metal ion. The …

Does Low-Level Arsenic Exposure Predict Blood Pressure In Children?, Tania Angelica Mayorga

Open Access Theses & Dissertations

Background & Significance: Inorganic arsenic is a heavy metal naturally found in soil and human exposure to this heavy metal causes adverse effects. Exposure risks are particularly high in developing children. Arsenic is mainly found in bedrock. It is also a by-product of smelting, it is used in cement production, and historically is has been found in crop pesticides. Among other ill-effects, arsenic exposure in humans can cause respiratory diseases, peripheral neuropathy and liver fibrosis. In particular arsenic has been shown in many studies to be a contributing factor in the risk for hypertension in adults however no studies have …

Comparison Of Blood Lead Levels Between Children In An Urban Setting And Children In A Rural Setting, Juan Manuel Alvarez

Open Access Theses & Dissertations

Environmental heavy metal exposure is a public health problem that is of great concern because it is highly toxic for children. The urban setting in downtown El Paso is historically known to be contaminated through various sources of contamination of heavy metals. The goal of this study was to compare whether children in a historically contaminated urban downtown area had significantly increased levels of lead exposure as compared to children in a demographically similar rural area approximately 20 miles north of the urban center, while controlling for gender and age. Cadmium and mercury were also measured for comparison purposes. It …

Investigation Of The Natural Degradation Of Selected Endocrine Disrupting Compounds In Wastewater, Toni Carrick

Open Access Theses & Dissertations

Endocrine disrupting compounds (EDCs) are a class of compounds that are of concern for their potentially adverse effects on fish, wildlife, and humans. They can cause developmental and reproductive anomalies at concentrations in the low ppb to ppt levels. Studies have shown the primary route of exposure of EDCs within the environment is through the discharge of effluent wastewater. Removal efficiencies of wastewater treatment plants have been studied extensively, however, in rural or developing areas, which often lack secondary or tertiary wastewater treatment, little is known about the stability of these compounds and the rate at which they degrade in …

An Assessment Of The Role Of Roads In Population Demography And Genetic Structuring In Two Species Of Lizards In The Northern Chihuahuan Desert, Kevin Floyd

Open Access Theses & Dissertations

Roads can fragment habitat and increase mortality rates of wildlife, potentially reducing population sizes and gene flow, which in turn can reduce genetic diversity through genetic drift. Although negative road impacts have been found in a variety of taxa, not all species are impacted. For instance, species that move less and rarely encounter roads and those that avoid the roads are predicted to not be negatively affected. Yet tests of these predictions are uncommon, especially for reptiles and particularly lizards. Side-blotched lizards (Uta stansburiana) are small sit-and-wait predators, while the larger marbled whiptails (Aspidoscelis marmorata) are active foragers. Their responses …

Latina/O High School Students' Standpoint On Environmental Justice In A Border Community: A Phenomenological Study, Cynthia Christina Ontiveros

Open Access Theses & Dissertations

This qualitative research is a transcendental phenomenology seeking to understand Latin@ high school students’ perceptions and standpoints as they participated lessons that addressed border environmental justice issues in an underrepresented, marginalized community. Seven students from Borderland High School, enrolled in a senior level course, Environmental Science, participated in the study which focused on their experiences in an environmental justice air quality thematic unit built around the complex issues surrounding a local refinery, American Smelting and Refining Company (ASARCO). The study analyzed the meaning students made and their standpoints regarding the impact of the factory and its one-hundred year history polluting …

Single And Multiple Objective Biomass-To-Biofuel Supply Chain Optimization Considering Environmental Impacts, Claudia Evangelina Valles Sosa

Open Access Theses & Dissertations

Bioenergy has become an important alternative source of energy to alleviate the reliance on petroleum energy. Bioenergy offers diminishing climate change by reducing Green House Gas Emissions, as well as providing energy security and enhancing rural development. The Energy Independence and Security Act mandate the use of 21 billion gallons of advanced biofuels including 16 billion gallons of cellulosic biofuels by the year 2022. It is clear that Biomass can make a substantial contribution to supply future energy demand in a sustainable way. However, the supply of sustainable energy is one of the main challenges that mankind will face over …

Impact Of Exposure To Weathered Crude Oil And Accumulation Of Pahs In Crawfish (Procambarus Clarkii), Brittany Lynn Chichester

LSU Master's Theses

The number of pipelines transporting crude oil and other refined petroleum products across the U.S. has increased 15.4% from 2004 to 2013. In Louisiana, over 3,450 miles of liquid petroleum pipelines crisscross the state. In January 2013, crude oil was accidentally released from an underground pipeline into Bayou Sorrel, Louisiana. This freshwater wetland is located within the Atchafalaya River Basin which is home to large populations of wild crawfish that could be impacted by the crude oil released. This study aims to assess the potential lethal impacts that crude oil spill may have produced in adult crawfish (P. clarkii) and …

Hybridization And Population Structure Of Western Gulf Coast Mottled Ducks, Robert Joseph Ford

LSU Master's Theses

Rates of hybridization between species that do not normally interbreed have increased due to human impacts on natural environments, such as habitat alteration or introductions of non-native species. Human-induced hybridization can be detrimental to wildlife and contribute to species extinctions. In Florida, feral Mallards (Anas platyrhynchos) hybridize with endemic Mottled Ducks (A. fulvigula) at rates close to 9%. However, levels of hybridization between these two species have not been extensively examined in the western Gulf Coast (from Alabama to northern Mexico) despite the potential impact on the Mottled Duck lineage. In this study, I examined the degree of hybridization between …

Effect Of The Herbicide Atrazine On Phytoplankton, Water Quality, And Ecosystem Functions In Louisiana Estuaries, Alexis Victoria Starr

LSU Master's Theses

Pesticides are used primarily for agricultural purposes in the US and while these chemicals provide many benefits, the inherent toxicity of the compounds pose a substantial risk to the environment. These chemicals may enter water bodies in areas with a high proportion of agricultural land use through surface run off, ground water discharge, and erosion, and negatively impact non-target aquatic organisms. As a result, Louisiana’s estuaries may be vulnerable to a variety of compounds, including the herbicide atrazine. Atrazine is used extensively throughout the Midwest and has been known to enter the Mississippi River through surface runoff and ground water …

Population Abundance And Transience Of Selected Coastal Plain Crayfishes, Samantha Lott

LSU Master's Theses

Crayfish are important for stability, determining ecosystem structure, and ecosystem functions in freshwater habitats. Louisiana has many endemic species of crayfish, but most are poorly described. This study investigated the populations of some of the lesser known crayfishes in the South Central Plains. Specifically, the goals were to examine movement, movement across anthropogenic barriers, and estimate population size of 10 species reported from the area: Procambarus natchitochae, P. vioscai, P. clarkii, P. acutus, P. zonangulus, P. tulanei, P. kensleyi, Orconectes maletae, O. lancifer, and O. palmeri. In combination with a field team, I sampled twelve wadeable streams with DC backpack …

If You Build It, What Will Come? Assessing The Avian Response To Wetland Restoration In The Mississippi River Bird’S Foot Delta Through Multiple Measures Of Density And Biodiversity, Lauren Rae Sullivan

LSU Master's Theses

Multiple wetland restoration and enhancement techniques are used in Louisiana to combat land loss and provide habitat for waterbirds. We investigated the avian response to three wetland restoration techniques in the Lower Mississippi Bird’s Foot Delta to determine if the different habitat types resulted in differences in the value of edge habitat. Species richness, guild richness, total bird density, bird density by foraging guild, and bird abundance relative to distance from the marsh edge was compared among (i) crevasse splays, a type of sediment diversion which allow the river to build new wetlands, (ii), beneficial use of dredged material marshes, …

A Botanical Survey Of Native And Non-Native Species Along The Three Rivers Greenway In Columbia, South Carolina, Rebecca L. Givens

Theses and Dissertations

Baseline surveys are important tools in establishing the present flora located within an area for future monitoring. In addition, knowledge of invasive species presence is essential to help maintain native ecosystem biodiversity. This study aimed to establish a baseline inventory of plant species found along a portion of the Three Rivers Greenway in Columbia, South Carolina, and to create a comprehensive list of native and invasive plant species within this area. In addition, a geographic information system (GIS) was employed to show the spread of a particular known invasive plant species, Hedera helix within the area. Specimens were collected in …

Correlation Analysis Of Climatic Variables, Migration And Dengue Cases In Southeast Florida, Brunilda Lugo

Walden Dissertations and Doctoral Studies

Dengue fever is a debilitating, viral, mosquito-borne disease occurring in tropical and subtropical areas in the world. The majority of dengue cases in the United States were acquired in endemic areas by travelers or immigrants. However, in recent years, autochthonous (locally acquired) dengue cases have been diagnosed in Florida. The purpose of this study was to find an association between potential risk factors and the expansion of dengue fever in the United States. Guided by the eco-bio-social framework, which offers a broad assessment of risk factors for the illness, a retrospective design was used with archival data to correlate changes …

Examination Of Field Scale Hydrological Processes Under Three Different Tillage Methods In Southern Ontario: Conventional Till (Ct); Modified Till (Mt); And No Till (Nt), Ian Martin

Theses and Dissertations (Comprehensive)

In the wake of the severe algal blooms of 2011 and 2013 in the Great Lakes, international governing bodies such as the United Nations, are advocating for increased studies on nutrient dynamics within agricultural systems. Understanding farm contributions to nutrient loads entering the Great Lakes involves quantifying nutrient export from different tillage practices common in the Great Lakes basin, which include no-till (NT), conventional till (CT) and modified tillage (MT). Understanding differences in nutrient export from different tillage practices may well be related to structural differences in the upper portion of the vadose zone which impact infiltration, soil moisture and …

Analyses Of Potential Ravine And Bluff Stabilization Sites Within The Blue Earth And Le Sueur River Basins, Anna My-Tien T. Tran

All Graduate Theses, Dissertations, and Other Capstone Projects

The United States Environmental Protection Agency (USEPA) has listed much of the Upper Mississippi River (UMR) basin as impaired waters due to excessive turbidity, sedimentation, and nutrient loading. Of particular importance are the associated environmental problems (e.g. eutrophication, habitat and wetland loss, loss of biodiversity, and changes in water quality) that have developed within Lake Pepin, a popular recreational riverine lake of the UMR. Three major drainages contribute to these issues and empty in to the UMR near Lake Pepin - the Minnesota River Basin (MRB), St. Croix River, and UMR. The MRB makes up approximately one-third of the drainage …

Using Sustainable Development As A Competitive Strategy, Pat Spearman

Walden Dissertations and Doctoral Studies

Sustainable development reduces construction waste by 43%, generating 50% cost savings. Residential construction executives lacking adequate knowledge regarding the benefits of sustainable development practices are at a competitive disadvantage. Drawing from the diffusion of innovation theory, the purpose of this qualitative case study was to explore knowledge acquisition within the bounds of sustainable residential construction. The purposive sample size of 11 executive decision makers fulfilled the sample size requirements and enabled the extraction of meaningful data. Participants were members of the National Home Builders Association and had experience of a minimum of 5 years in residential construction. The research question …

Rural Year-Round Growing To Ameliorate A Possible Negative Effect From Climate Change, Kimberlie A. Brussa

Walden Dissertations and Doctoral Studies

The Intergovernmental Panel on Climate Change (IPCC) suggested that, as the world population grows, food and water shortages will become even more serious issues (IPPC's 2014 predictions about the future effects of climate change (CC), Year-round growing (YRG) may provide a way for communities to extend growing seasons, expand local farm systems, and provide food year round. This case study included a detailed analysis of responses from representatives of all sectors of rural Mesa County, Colorado, regarding YRG and a local food and farm plan due to CC. The case was bounded by time (6 months of data collection) which …

Dynamically Hedging Oil And Currency Futures Using Receding Horizontal Control And Stochastic Programming, Paul Edward Cottrell

Walden Dissertations and Doctoral Studies

There is a lack of research in the area of hedging future contracts, especially in illiquid or very volatile market conditions. It is important to understand the volatility of the oil and currency markets because reduced fluctuations in these markets could lead to better hedging performance. This study compared different hedging methods by using a hedging error metric, supplementing the Receding Horizontal Control and Stochastic Programming (RHCSP) method by utilizing the London Interbank Offered Rate with the Levy process. The RHCSP hedging method was investigated to determine if improved hedging error was accomplished compared to the Black-Scholes, Leland, and Whalley …

Proof-Of-Concept Of Environmental Dna Tools For Atlantic Sturgeon Management, Jameson Hinkle

Theses and Dissertations

Abstract

The Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus, Mitchell) is an anadromous species that spawns in tidal freshwater rivers from Canada to Florida. Overfishing, river sedimentation and alteration of the river bottom have decreased Atlantic Sturgeon populations, and NOAA lists the species as endangered. Ecologists sometimes find it difficult to locate individuals of a species that is rare, endangered or invasive. The need for methods less invasive that can create more resolution of cryptic species presence is necessary. Environmental DNA (eDNA) is a non-invasive means of detecting rare, endangered, or invasive species by isolating nuclear or mitochondrial DNA (mtDNA) from the …

The Tragicomedy Of The Commons, Brigham Daniels

BYU Law Review

Scholarship on the commons focuses on a diverse set of problems, ranging from crashing fisheries to crowded court dockets. Because we find commons resources throughout our natural and cultural environments, understanding old lessons and learning new ones about the commons gives us leverage to address a wide range of problems. Because the list of resources identified as commons resources continues to grow, the importance of gleaning lessons about the commons will also continue to grow.

That being said, while the resources that make up the commons are certainly diverse, so too are the ways scholars depict it and the challenges …

Current Legal Framework On South Africa And Cameroon Relating To Plastic Pollution To The Environment On A Comparative Basis : Case Study : South Africa And Cameroon, Temah Larry Besong Ndi

World Maritime University Dissertations

The objective of these studies is to compare the environmental laws of South Africa and Cameroon with focus on plastic pollution laws on both nations, with a yard stick of that of IMO international conventions. The reason to better the environmental laws of Cameroon, copying that of South Africa which is very much advanced and are signatories to several IMO conventions, in abide to put Cameroon administration on same level. The importance of the marine environment need not be over emphasis as the plastics pollution is now a global concerned and Cameroon at the mouth of Atlantic Ocean, with a …

Texas Groundwater And Tragically Stable “Crossovers”, Zachary Bray

BYU Law Review

One recurring question in the academic literature on common-pool resources relates to the persistence of “tragic” commons regimes—systems that encourage, or at least tolerate, the inefficient, wasteful, hazardous, or unfair exploitation of a resource that is easily accessed for and diminished by individual use and consumption. Of course, not all commons are tragic: some common-pool resources invite individual access in efficient, fair, and durable ways. Yet many commonly held resources do lie under systems of governance that are not just tragic but persistently and stubbornly so. Often the tragic aspects of such commons regimes are well known; indeed, for some …

Naming The Tragedy, Eric T. Freyfogle

BYU Law Review

No abstract provided.

Isolated Wetland Commons And The Constitution, Blake Hudson, Mike Hardig

BYU Law Review

Isolated wetlands provide great ecological and economic value to the United States. While some states provide protection for isolated wetlands, a great many do not. These wetlands are also left outside the ambit of federal wetland regulatory protections under the Clean Water Act, with its murky jurisdictional reach. Notwithstanding jurisdictional questions under current federal statutes, the U.S. Supreme Court has gone so far as to call into question the constitutionality of federal isolated wetland regulation. This Article makes a normative argument that, in the absence of state or local programs providing holistic isolated wetland protection, federal action is needed. The …

Registration Of ‘Newell’ Smooth Bromegrass, K P. Vogel, R B. Mitchell, B L. Waldron, M R. Haferkamp, J D. Berdahl, D D. Baltensperger, Galen Erickson, T J. Klopfenstein

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.