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Full-Text Articles in Physical Sciences and Mathematics

Charismatic Predators In Modern Africa: Spotted Hyena (Crocuta Crocuta) And Human Coexistence In The Northern Tuli Game Reserve, Botswana, Jazmin Castillo May 2020

Charismatic Predators In Modern Africa: Spotted Hyena (Crocuta Crocuta) And Human Coexistence In The Northern Tuli Game Reserve, Botswana, Jazmin Castillo

School of Natural Resources: Dissertations, Theses, and Student Research

Increasing human populations has led researchers to investigate the impacts of high human population density and its impact on carnivore populations. Spotted hyenas (Crocuta crocuta) hold a unique place in African ecosystems due to being a very successful top predator with an adaptable diet whereas other top predators, like the African lion, are rapidly decreasing in abundance. We investigated past and current spotted hyena abundance within the Northern Tuli Game Reserve to better aid in wildlife management. Spotted hyenas showed no significant difference in the change in population abundance throughout the different years of the study (2008-2016). Spotted …


Promoting The Sustainable Utilization Of Groundwater Resources In Ethiopia Using The Integrated Groundwater Footprint Index, Xinyu Lin May 2020

Promoting The Sustainable Utilization Of Groundwater Resources In Ethiopia Using The Integrated Groundwater Footprint Index, Xinyu Lin

Honors Scholar Theses

The country of Ethiopia is highly vulnerable to human-caused climate change and is already suffering from the effects. The predominately rural population relies heavily on small-scale agriculture, with 78% of households having at least one member engaged in the field, yet staple crops are highly susceptible to droughts and other weather shocks. Total and agricultural GDP growth in the country have been strongly linked to inter-annual rainfall variability, of which Ethiopia has among the highest in sub-Saharan Africa. A decrease in rainfall since the 1970s has been one of the primary causes of low crop yields, and stresses the immediate …


Habitat Modification On An Urban High School Campus, Nickolas John Davros Ii May 2020

Habitat Modification On An Urban High School Campus, Nickolas John Davros Ii

Graduate Theses

Biodiversity is in a crisis worldwide, driven by the negative effects from urbanization. Ecosystems are being destroyed in favor of urban areas and natural resources are diminishing. Stormwater management has gained an elevated importance and its associated infrastructure could help counter the loss of biodiversity. Freshwater within urban areas is critical for organisms. Anthropogenic ponds can act as refuge habitats within a blue network and have become a hotspot for ecological research. Using principles of reconciliation ecology, the effects on biodiversity were assessed following the conversion of a stormwater basin on an urban high school in Charlotte, NC. A before-and-after …


Impact Of Agricultural Land Use On Stream Nitrate, Phosphorus, And Sediment Concentrations At The Watershed And Field Scale, Brittany A. Kirsch May 2020

Impact Of Agricultural Land Use On Stream Nitrate, Phosphorus, And Sediment Concentrations At The Watershed And Field Scale, Brittany A. Kirsch

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Water quality is directly impacted by the landscape through which it travels. As such, land use, including summer annual and winter annual/perennial agriculture, has dramatic influence on the water quality of downstream aquatic and terrestrial ecosystems. I examined the impact of agricultural land use on water quality through two projects, one at a watershed scale and one at a field scale. In my first project, I investigated the impact of agricultural land use and climate on water quality in 13 HUC10 watersheds across Nebraska using public data from US Geological Survey (USGS), US Department of Agriculture National Agricultural Statistics Service …


Changes In Land Use Land Cover (Lulc), Surface Water Quality And Modelling Surface Discharge In Beaver Creek Watershed, Northeast Tennessee And Southwest Virginia, Tosin James May 2020

Changes In Land Use Land Cover (Lulc), Surface Water Quality And Modelling Surface Discharge In Beaver Creek Watershed, Northeast Tennessee And Southwest Virginia, Tosin James

Electronic Theses and Dissertations

Beaver Creek is an impaired streams that is not supporting its designated use for recreation due to Escherichia coli (E.coli), and sediment. To address this problem, this thesis was divided into two studies.

The first study explored changes in Land Use Land Cover (LULC), and its impact on surface water quality. Changes in E.coli load between 1997-2001 and 2014-2018 were analyzed. Also, Landsat data of 2001, and 2018 were examined in Terrset 18.31. Mann-Whitney test only showed a significant reduction in E.coli for one site. Negative correlation was established between E.coli load, and Developed LULC, Forest LULC, and …


An Analysis Of Groundwater Quality As Sampling Networks Age: The Gaps In Groundwater Monitoring, Angela Leone May 2020

An Analysis Of Groundwater Quality As Sampling Networks Age: The Gaps In Groundwater Monitoring, Angela Leone

Undergraduate Distinction Papers

Groundwater management is an important facet of protecting this important resource. One way that we ensure proper groundwater management is through the regular, long-term monitoring of groundwater wells at waste management sites throughout the country. This study investigates potential changes to groundwater quality attributed to degradation of well construction materials rather than impacts to aquifers from wastes. This assessment was completed using a data analysis of groundwater trends at closed landfill sites. An analysis of fifty-five sites was completed and three sites met our criteria for suitable data history. Due to the lack of suitable data, a more thorough investigation …


Private Land, Public Trust: Strategic Conservation Planning For Public Wildlife On Private Lands Through The Usfws Partners For Fish And Wildlife Program, Clint Wirick May 2020

Private Land, Public Trust: Strategic Conservation Planning For Public Wildlife On Private Lands Through The Usfws Partners For Fish And Wildlife Program, Clint Wirick

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Law requires federal agencies to develop long-term strategic plans. Strategic plans define goals, objectives, and performance measures defining how the agencies and programs will reach their stated goals. U.S. Fish and Wildlife Service’s Partners for Fish and Wildlife (PFW) develops strategic plans every five years. Each individual state develops a plan for their respective state. Those state plans are compiled for the region and become part of Regional Comprehensive Strategic Plan. The current strategic plan expires in 2021. States will begin the strategic planning process in 2020. In Utah, PFW staff will also begin developing a strategic plan for the …


Identifying Emergent Agent Types And Effective Practices For Portability, Scalability, And Intercomparison In Water Resource Agent-Based Models, Kendra E. Kaiser, Alejandro N. Flores, Vicken Hillis May 2020

Identifying Emergent Agent Types And Effective Practices For Portability, Scalability, And Intercomparison In Water Resource Agent-Based Models, Kendra E. Kaiser, Alejandro N. Flores, Vicken Hillis

Geosciences Faculty Publications and Presentations

Modeling coupled social and biophysical dynamics of water resources systems is increasingly important due to population growth and changes in the water cycle driven by climate change. Models that explicitly represent these coupled dynamics are challenging to design and implement, particularly given the complicated and cross-scale nature of water governance. Agent-based models (ABMs) can capture human decision-making and nested social hierarchies, however, transferability is made difficult by location-specific details. A consistent description of water resources decision-makers (individuals, groups, agencies) would advance the rate of model development and increase synthesis across systems. Reviewing water resources ABMs, we propose eight agent types …


Record Fledging Count From A Seven-Egg Clutch In The Cooper’S Hawk (Accipiter Cooperii), Robert N. Rosenfield, Sarah A. Sonsthagen, Ann Riddle-Berntsen, Evan Kuhel May 2020

Record Fledging Count From A Seven-Egg Clutch In The Cooper’S Hawk (Accipiter Cooperii), Robert N. Rosenfield, Sarah A. Sonsthagen, Ann Riddle-Berntsen, Evan Kuhel

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Cooper’s Hawks (Accipiter cooperii) typically lay 3–5 eggs per clutch, rarely 6 eggs, and there are 2 accounts of 7-egg clutches and 1 record of a maximum 8-egg clutch for the species. Brood sizes of 3–5 young are common and the previous maximum brood count is 6 young. However, in 2019, we found an urban nest in Stevens Point, Wisconsin, with 7 eggs that resulted in a record high of 7 fledglings. We genetically confirmed that the attending male sired all the offspring and the attending female laid all 7 eggs. Larger body size of the tending adults …


Building Adaptive Capacity In Tribal Communities Of The Missouri River Basin To Manage Drought And Climate Extremes: A Case Study From The Wind River Indian Reservation, Crystal J. Stiles, Natalie Umphlett, Mitch Cottenoir May 2020

Building Adaptive Capacity In Tribal Communities Of The Missouri River Basin To Manage Drought And Climate Extremes: A Case Study From The Wind River Indian Reservation, Crystal J. Stiles, Natalie Umphlett, Mitch Cottenoir

High Plains Regional Climate Center: Personnel Publications

Native American peoples of the Northern and Central Plains have long endured harsh climate conditions, such as floods and droughts, and they possess valuable traditional knowledges that have enhanced their resilience to these extreme events. However, in recent times, limited capacity to adapt to a rapidly changing climate combined with a lack of resources have increased tribes’ vulnerability to climate extremes and their associated impacts. In response, a number of projects have been developed to assist tribes with their self-identified climate- and drought-related needs, particularly in the context of on-reservation decision-making. In this case study, we present an engagement strategy …


Sustainable Wastewater Treatment In The American South, Caroline Miles May 2020

Sustainable Wastewater Treatment In The American South, Caroline Miles

Master's Theses

Aging infrastructure and changing social and environmental conditions are two factors that are currently pushing wastewater treatment towards more sustainable methods. This thesis investigates what sustainable treatment technologies are being used in the American South through a focused sample of six cities across the region: Austin, Texas; Fayetteville, Arkansas; Hattiesburg, Mississippi; Memphis, Tennessee; Ocean Springs, Mississippi; and Tuscaloosa, Alabama. The study assesses the types of sustainable treatment technology utilized at each facility, the perspectives of wastewater professionals about the technology, and the economic and environmental sustainability of each facility. Data was collected through direct observations on tours of the facilities, …


Assessing Predictors Of Harmful Algal Blooms In The Western Lake Erie Basin., Katherine M. Weigle May 2020

Assessing Predictors Of Harmful Algal Blooms In The Western Lake Erie Basin., Katherine M. Weigle

Electronic Theses and Dissertations

Harmful algal blooms (HABs) have been a recurring issue in the Western Lake Erie Basin for more than a decade, despite policies implemented to improve the water quality of the Great Lakes. HABs describe algae that can be harmful to both ecosystem function and human health. The Western Lake Erie Basin, in particular, experiences Microcystis aeruginosa blooms in the summer months due to a multitude of factors leading to increased phosphorus and nitrogen loads in the contributing watersheds. In this study, lake water surface temperature, land cover, river discharge, and precipitation were examined as potential triggers for the occurrence and …


Analyzing The Effects Of Of Seasonal Land Cover And Precipitation On The Sediment Delivery Ratio Of An Agriculture Dominated Watershed., Jonah Liebman May 2020

Analyzing The Effects Of Of Seasonal Land Cover And Precipitation On The Sediment Delivery Ratio Of An Agriculture Dominated Watershed., Jonah Liebman

Electronic Theses and Dissertations

Soil erosion is of escalating importance as increasing population and climate change have put increasing pressures on agricultural food production. Vegetation and precipitation are two factors that control the amount of soil erosion extant within a region. Sediment delivery ratios (SDRs) assess the ratio of soil eroded from a watershed system that is permanently removed from the system through stream sediment discharge. Using 1) river discharge and sediment concentration data and 2) the Revised Universal Soil Loss Equation (RUSLE), this thesis analyzes fluctuations in monthly SDRs for an average hydroclimatological crop-harvest season for the Senachwine Creek watershed, IL. Through calculating …


The Release, Transport, And Utilization Of Phosphorus From Bed-Sediments: A Study Of A Eutrophic Littoral Cove On Beaver Lake In Northwest Arkansas, James A. Mccarty May 2020

The Release, Transport, And Utilization Of Phosphorus From Bed-Sediments: A Study Of A Eutrophic Littoral Cove On Beaver Lake In Northwest Arkansas, James A. Mccarty

Graduate Theses and Dissertations

Eutrophication of surface waters not only impacts the environment but also water treatment processes, the most significant of which is from the effects of algae. During peak algal growth in many southern U.S. reservoirs, inflows that bring nutrients are at an annual minimum, and phosphorus released from bed-sediments is trapped in the hypolimnion. Littoral areas, described as the most productive zone of the lake, may be a possible source of phosphorus that fuels algal growth in the reservoir. I studied an isolated shallow cove in the War Eagle Creek arm of Beaver Lake in Northwest Arkansas to measure, quantify, and …


Development Of Vs Profiles And Site Periods In The Mexico City Basin, Landon Joel Woodfield May 2020

Development Of Vs Profiles And Site Periods In The Mexico City Basin, Landon Joel Woodfield

Graduate Theses and Dissertations

This study presents dynamic site characterization measurements at 25 sites within the Mexico City Basin. The primary focus of the testing was along the western edge of the Mexico City Basin. At each site, active source Multi-channel Analysis of Surface Waves (MASW) arrays and passive source Microtremor Array Measurements (MAM) L-arrays and circular arrays were used to acquire dispersion data. Horizontal to Vertical Spectral Ratio (HVSR) data was collected to determine site periods at each location. These experimental dispersion data and site periods were fit using a joint inversion of Rayleigh and Love wave dispersion data and HVSR site period …


Surface Modified Polypropylene Membranes For Treating Hydraulic Fracturing Produced Waters By Membrane Distillation, Tharaka Hawpe Gamage May 2020

Surface Modified Polypropylene Membranes For Treating Hydraulic Fracturing Produced Waters By Membrane Distillation, Tharaka Hawpe Gamage

Graduate Theses and Dissertations

Membrane distillation is an emerging technology for treating hydraulic fracturing flowback and produced waters. Suppression of membrane fouling by inorganic and polar and non-polar organic compounds is a challenge. Here polyhydroxyethyl methacrylate, polyacrylic acid, polvinylallyl imidazolium bromide and polyvinylhexyl imidazolium bromide chains have been grafted from the membrane surface. Fouling is initially due to adsorption of organic compounds followed by scale formation. When challenged with produced water, membranes modified with polvinylallyl imidazolium bromide chains provided the greatest resistance to fouling. For EC pretreated produced water and synthetic produced water that contained mainly inorganic species, the flux decline was much less.


Cost Benefit Analysis And Beyond: Stream Restoration In Richmond, Virginia, Claire Powell Apr 2020

Cost Benefit Analysis And Beyond: Stream Restoration In Richmond, Virginia, Claire Powell

Environmental Studies Senior Seminar Projects

This research assessed the costs and benefits of six recent stream restoration projects in Richmond, Virginia within the context of the Chesapeake Bay Total Maximum Daily Load (CB TMDL) pollutant reduction requirements. In order to meet these requirements, state and local governments promoted stream restoration as an important way to reduce Bay-wide inputs of nitrogen, phosphorus, and total suspended solids. The overall intention of this paper was to holistically evaluate the risks and positive impacts associated with stream restoration, with a focus on Little Westham Creek, a stream restoration project located on the University of Richmond campus. I hypothesized that …


Sediment Outflow Under Simulated Rainfall Conditions With Varying Geotechnical Properties, Pranjay Joshi, Akhilesh Kumar, P. V. Singh, Jahangeer Jahangeer Apr 2020

Sediment Outflow Under Simulated Rainfall Conditions With Varying Geotechnical Properties, Pranjay Joshi, Akhilesh Kumar, P. V. Singh, Jahangeer Jahangeer

Daugherty Water for Food Global Institute: Faculty Publications

The vulnerability of soil toward erosion might be reduced by having a good vegetative cover over the soil surface, slope improvement, and improving soil properties so that it is not easily detached and transported. However, the establishment of proper vegetative cover is a long process because it takes time for seeds to germinate and attain maturity. As an alternative approach, if soil resistance was increased by increasing the shear strength of soil against erosive forces offered by eroding agents, the soil system would become capable of withstanding the detachment of its particles on the application of shear stress. To achieve …


The Effects Of Temperature On Evacuation Rates And Absorption Efficiency Of Flathead Catfish, Zach Horstman Apr 2020

The Effects Of Temperature On Evacuation Rates And Absorption Efficiency Of Flathead Catfish, Zach Horstman

School of Natural Resources: Dissertations, Theses, and Student Research

Knowledge of fish gastric evacuation rates are a necessary component for both field and laboratory studies when trying to understand feeding rates, modeling energy budgets, and understanding trophic dynamics of aquatic ecosystems. Many freshwater fish encounter a broad range of environmental temperatures across life history stages, but the mechanistic link between temperature and physiological processes often remains poorly understood. We designed three recirculating aquatic systems capable of rearing Flathead Catfish Plyodictis olivaris in order to quantify gastric evacuation rates and gross energy absorption at three temperatures (17º C, 22º C and 25º C). We examined the relationship between temperature and …


In Hot Water: Influence Of Multiple Stressors On Thermal Tolerance Of Fathead Minnows Pimephales Promelas, Alexander Engel Apr 2020

In Hot Water: Influence Of Multiple Stressors On Thermal Tolerance Of Fathead Minnows Pimephales Promelas, Alexander Engel

School of Natural Resources: Dissertations, Theses, and Student Research

Freshwater aquatic systems around the globe are often subjected to physical, biological, and chemical alterations to support societal needs. The Great Plains contains one of the largest agricultural industries in North America, but its productivity has ecological repercussions for adjacent freshwater ecosystems. Specifically, the dependency on surface water irrigation and application of chemical treatments has altered the thermal and chemical composition of freshwater ecosystems throughout the region. Stressors such as elevated temperatures, altered flow regimes, increased contaminant loads affect the physiology and behavior of fishes and can lead to long-term population effects. We examined thermal tolerance of Fathead minnows Pimephales …


Community Involvement In Flood Mitigation: A Survey-Based Approach In Marion County, Sc, Lillian C. Howie Apr 2020

Community Involvement In Flood Mitigation: A Survey-Based Approach In Marion County, Sc, Lillian C. Howie

Electronic Theses and Dissertations

Marion County is located in northern South Carolina between the Great Pee Dee and Little Pee Dee Rivers. Because Marion County was the location of severe flooding during hurricanes Matthew (2016) and Florence (2018), the South Carolina Floodwater Commission identified Marion County as a location for drainage system improvement by the Infrastructure and Shoreline Armoring Task Force. In order to align plans for drainage system improvement with the needs of the local communities, commission chairman Thomas Mullikin requested a community survey to gauge the residents' personal experiences and views on what changes should be made to address the problem. The …


Modeling Drought, Drought Teleconnection, And Its Effect On Groundwater Level Dynamics In The Biscayne Aquifer, Anteneh Z. Abiy Apr 2020

Modeling Drought, Drought Teleconnection, And Its Effect On Groundwater Level Dynamics In The Biscayne Aquifer, Anteneh Z. Abiy

FIU Electronic Theses and Dissertations

Developing a self-sufficient water supply system in Southeast Florida is one input to the success of the ongoing restoration effort in the Everglades. Maintaining a high groundwater level in the urban side of the Biscayne Aquifer (BA) is important to sustain the urban water supply. However, the long-term groundwater table condition in the Biscayne Aquifer (BA) is threatened by a combination of drought, groundwater pumping, and sea-level rise. Further, the long-term drought pattern, drought drivers, and the aquifer’s response to drought and other stress conditions are not well known. As a result, options that would help to maintain a high …


Impact Of Streambank Stabilization On Sediment Deposition And Erosion In Central Nebraska Streams, Matthew Russell Apr 2020

Impact Of Streambank Stabilization On Sediment Deposition And Erosion In Central Nebraska Streams, Matthew Russell

School of Natural Resources: Dissertations, Theses, and Student Research

Stabilization projects are increasingly used to mitigate the effects of anthropogenic streambank erosion, yet the effectiveness of these practices has been insufficiently monitored and assessed to date. Sound monitoring practices promote engineered effectiveness, in addition to allowing adjustments in implementation and maintenance to improve practices over time. However, current methods to quickly and efficiently quantify deposition and erosion within a stream continue to be costly and inefficient. Therefore, the objectives of this project were to 1) Measure streambank migration of three reaches at Cedar River in Nebraska, from 1993 to 2006 (pre-stabilization) and from 2006 to 2018 (post-stabilization) using aerial …


Drinking Water Governance For Whom? An Institutional Analysis Of Rural Drinking Water Systems In New Mexico, Tucker Colvin Apr 2020

Drinking Water Governance For Whom? An Institutional Analysis Of Rural Drinking Water Systems In New Mexico, Tucker Colvin

Geography ETDs

Rural community drinking water systems in New Mexico are facing many challenges, including a lack of personnel, deteriorating infrastructure, lack of funds, overly burdensome and confusing regulation, environmental concerns, and concerns over water rights. Governing agencies are creating vulnerability by making managers prioritize some issues and neglect others. Water systems designated a Mutual Domestic Water Consumers Associations are especially problematic because they are small and managed by volunteers but have as much regulatory burden as larger municipalities. I use the theory of institutional work to explain how an institution that was originally designed to help low-income and rural communities is …


Water Supply Capacity Development In The Context Of Global Change, Patrick Breach Apr 2020

Water Supply Capacity Development In The Context Of Global Change, Patrick Breach

Electronic Thesis and Dissertation Repository

The ANEMI model is an integrated assessment model of global change that emphasizes the role of water resources. The model is based on the principles of system dynamics simulation in order to analyze changes in the Earth system using feedback processes. Securing water resources for the future is a key issue of global change, and ties into global systems of population growth, climate change carbon cycle, hydrologic cycle, economy, energy production, land use and pollution generation.

This thesis focusses on the development of global water supplies necessary to keep pace with a growing population and global economy using an integrated …


Water 4.0, Arthur Preston Apr 2020

Water 4.0, Arthur Preston

OHSU-PSU School of Public Health Annual Conference

A review of local drinking water quality/technologies, and strategies to improve water quality using emerging next generation technology.


Biogeography Of Biological Control: Spatial Variation In Agent-Host Interactions, Nathan Harms Apr 2020

Biogeography Of Biological Control: Spatial Variation In Agent-Host Interactions, Nathan Harms

LSU Doctoral Dissertations

Management of plant invasions using biological control has the potential to generate spatial patterns which reflect geographic or genetic variation in invader or control agents. Despite its rarity in practice, investigations into the biogeography of interacting species (i.e., plant invader and control agent) in the context of biological control can lend insights into species distribution-abundance patterns and provide predictions for spatial variation in control success. I explored spatial variability in biological control agent-plant interactions using two wetland weed study systems with large geographic distributions: flowering rush (Butomus umbellatus L.) and alligatorweed (Alternanthera philoxeroides (Mart.) Griseb). Through literature and …


Exploring How Graduates Of The Nebraska Water Leaders Academy Influence Community Capitals: Two Case Studies, Dakota Staggs Apr 2020

Exploring How Graduates Of The Nebraska Water Leaders Academy Influence Community Capitals: Two Case Studies, Dakota Staggs

School of Natural Resources: Dissertations, Theses, and Student Research

Natural resources are foundational to any community and so leadership regarding those resources is a key factor to consider in order to understand communities. The vitality and strength of a community, however, is not solely dependent upon the natural resources available to it but depends on the collection of assets and individuals within it. This study sought to understand how individual leaders, graduates of the Nebraska Water Leaders Academy, influence each of the seven community capitals outlined by Flora, Flora, and Gasteyer (2016), and how their individual civic capacity, as defined by Sun and Anderson (2012), contribute to community capacity. …


Protecting Water Quality In Virginia: Recommendations To Combat Sea Level Rise And Increased Storm Events, Madhavi Kulkarni Apr 2020

Protecting Water Quality In Virginia: Recommendations To Combat Sea Level Rise And Increased Storm Events, Madhavi Kulkarni

Virginia Coastal Policy Center

Impairment of Virginia waters is tied to coastal storm hazards and sea level rise because excess floodwaters are contaminated by flood-exposed industrial and residential facilities, and these toxic floodwaters flow into the state’s water bodies. In Virginia, thousands of industrial facilities can potentially be subjected to the effects of stormwater flooding, hurricane storm surge, and sea level rise, in turn affecting water quality. Failing or unmaintained septic systems also pose a major threat to the quality of Virginia waters that increases with recurrent inundation by flood waters. A combination of changes to law and policy and investment in infrastructure are …


Water Current, Volume 52, No. 1, Spring 2020 Apr 2020

Water Current, Volume 52, No. 1, Spring 2020

Water Current Newsletter

MOD$$AT: Ogallala Water CAP’s Integrated Model

The Lowdown on Soil Moisture Monitoring

Innovations in Forages and Grazing in the High Plains