Digital Commons Network^™

Aerosol Physical And Chemical Properties Over Tropical Atlantic Ocean, Elsa Castillo

Open Access Theses & Dissertations

The atmospheric aerosol mass size distributions, modal characteristics, and a comparative analysis of the characteristic of PM2.5 versus trace gases: CO, O3, and SO2 over tropical Atlantic Ocean have been evaluated for Nov-Dec 2013. This study took place during the IX AEROSE expedition while the National Oceanic and Atmospheric Administration (NOAA) research vessel Ronald H. Brown traveled south along 23°W between 3°N and 5°S.

Aerosol mass size distributions were measured directly with a California Instruments Model PC-2H Quartz Crystal Microbalance (QCM). The corresponding values of average mass for accumulation, nuclei and coarse mode obtained were: 0.00124±0.00077, 0.00506±0.00254, and 0.00176±0.00114 μg/m …

Remaking Nature In Montana: Topophilic Considerations Of Wolves And Wolf Trapping, Andrew Myers

Graduate Student Theses, Dissertations, & Professional Papers

In 2011, after nearly forty years of federal protection, the gray wolf was removed from the Endangered Species List in Montana and its management entrusted to the Montana Fish, Wildlife & Parks. The implementation of public trapping seasons in 2012 as a method to control wolf populations has further inflamed an already embroiled debate. The purpose of this research was to investigate how the presence of wolves and wolf trapping impacts human attachments to landscapes of “nature” in Montana by focusing on the following questions: What are the public’s social constructions of wolves? What are the public’s social constructions of …

Linking The Effects Of Risk Factors On Annual Calf Survival To Elk Population Dynamics In The Bitterroot Valley, Montana, Daniel R. Eacker

Graduate Student Theses, Dissertations, & Professional Papers

The recolonization of gray wolves (Canis lupus) in multiple carnivore systems has been correlated with declining recruitment of juvenile ungulates, but the importance of wolves relative to other established carnivores is uncertain. The realized effect of carnivores may depend on compensation from forage and winter weather severity, which may mediate juvenile vulnerability to predation. Also, in high predation systems, the importance of juvenile recruitment may be reduced for ungulate population dynamics. We first tested for the effects of risk factors on annual elk (Cervus elaphus) calf survival and estimated cause-specific mortality rates. Secondly, we investigated the …

An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Bronc Mcmurtry

Electronic Theses and Dissertations

Four different grazing systems: two rotational, a continuous, and a high-intensity, short-duration (mob) system, replicated twice, were evaluated from an economic perspective. Mob grazing is defined as a system having very high stocking rates for a small amount of time. Livestock are forced to eat or trample the vegetation. Stocking rates and average daily gains (ADG) were collected from the UNL Barta Brothers ranch near Rose, Nebraska. The study started in 2011 and lasted until 2014. Using the performance data and other cost data relevant to South Dakota and Nebraska, budgets were set up for each system and extrapolated to …

Population Ecology Of Rocky Mountain Elk In The Black Hills, South Dakota And Wyoming, Benjamin D. Simpson

Electronic Theses and Dissertations

We conducted a 2-year (2012–2013) study of survival and cause–specific mortality using individually marked adult cow and neonate elk (Cervus elaphus) occupying the southwestern region of the Black Hills. We used known-fate analysis in Program MARK for survival analysis of adult cows and calves. We estimated survival and cause-specific mortality of 49 adult female elk over the 2 years of the study. Annual adult cow survival was 0.85 (95% CI = 0.72–0.87). We documented 12 mortalities with harvest (58.3%) and predation (16.6%) accounting for the majority of known mortalities. We captured and fit 71 neonates < 10 days of age with expandable Very High Frequency (VHF) radiocollars during summer 2012 (n = 37) and 2013 (n = 34). Annual (12 month) survival of elk calves was 0.75 (95% CI = 0.61–0.84) while summer (20 weeks; 15 May–25 September) survival was 0.79 (95% CI = 0.68–0.88). Predation accounted for 87.5% of mortalities; remaining mortalities were from starvation (6.3%) and unknown (6. 3%) causes. We used Global Positioning System (GPS) collars to collect 167,707 locations to determine home range, movement ecology, and macroscale resource selection of 48 adult cow elk. We documented elk using a variety of migration strategies (obligate migrator, resident, conditional migrator, disperser); the majority of the population (58%) was migratory. Spring migration distance travelled ranged from 2.45 km – 74.44 km (n = 42); fall migration distances ranged from 6.41km – 153.95 km (n = 46). We used 99% Brownian Bridge Movement Models to create seasonal and overall home ranges of adult cow elk. Mean overall home range size for conditional migrators was 249.28 km2 (SE = 28.60, n = 7, range = 233.75), for obligate migrant elk it was 227.18 km2 (SE = 13.94, n = 29, range = 346.83), and for resident elk it was 175.65 km2 (SE = 22.75, n = 11, range = 216.04). We used discrete choice models to determine resource selection at the macro-habitat scale of collared adult elk using ArcMap 10.1 data. Adult cow elk selected for open grassland/herbaceous areas and early successional forest areas close to forested edges at higher elevations. Our study showed that elk populations have the ability to thrive within an ecosystem with healthy predator populations.

Natural Nutrient Sources In The Cache River Watershed, Arkansas, M. K. Kilmer, N. Poe, S. Chappell, J. L. Bouldin

Journal of the Arkansas Academy of Science

The growth of the hypoxic ‘dead zone’ in the Gulf of Mexico in recent years has placed increased focus on potential sources of nutrient pollution, with most of the focus being placed on watersheds where practices, including fertilizer application and land alterations combine to increase non-point source runoff. In this study, nutrient concentrations in surface waters of altered and unaltered areas of the Cache River Watershed, Arkansas, were compared to determine if agricultural land usage was responsible for the majority of nutrient inputs. Results suggest that for dissolved nitrites and orthophosphates, agricultural (altered) sites contribute significantly more than relatively unaltered …

Quantification Of Food Waste Disposal In The United States: A Meta-Analysis, Krista L. Thyberg, David J. Tonjes, Jessica Gurevitch

Technology & Society Faculty Publications

Food waste has major consequences for social, nutritional, economic, and environmental issues, and yet the amount of food waste disposed in the U.S. has not been accurately quantified. We introduce the transparent and repeatable methods of meta-analysis and systematic reviewing to determine how much food is discarded in the U.S., and to determine if specific factors drive increased disposal. The aggregate proportion of food waste in U.S. municipal solid waste from 1995 to 2013 was found to be 0.147 (95% CI 0.137-0.157) of total waste, which is lower than that estimated by USEPA for the same period (0.176). The proportion …

Summary Of The Kentucky River Watershed Watch 2015 Water Sampling Results, Kentucky Water Resources Research Institute

Kentucky River Watershed Watch

No abstract provided.

The Effects Of Chanellization And Channel Restoration On Aquatic Habitat And Biota Of The Pecos River, New Mexico, Darrel J. Mecham

Electronic Theses and Dissertations

River channelization has been shown to negatively impact riverine ecosystems by degrading aquatic habitat conditions, decreasing diversity of both fish and aquatic invertebrate assemblages and impairing fish recruitment. As knowledge of the negative impacts of channelization has increased, so have channel restoration efforts. We evaluated a recent channel restoration project on the Pecos River, New Mexico by comparing abiotic and biotic conditions among five reaches of river, including the restored reach, an unchannelized reach and a channelized reach all prone to streamflow intermittence and an unchannelized reach and channelized reach more perennial in nature. Our first objective was to assess …

Healthy Outside-Healthy Inside: The Human Health & Well-Being Benefits Of Alberta's Protected Areas - Towards A Benefits-Based Management Agenda, Christopher J. Lemieux, Sean T. Doherty, Paul F.J. Eagles, Joyce Gould, Glen T. Hvenegaard, Elizabeth (Lisa) Nisbet, Mark W. Groulx

Geography and Environmental Studies Faculty Publications

This report details the results of an empirical study that examined perceived health and well-being motives and benefits among visitors to a sample of Alberta’s parks and protected areas. The study revealed several major findings with important policy and management implications. First, the human health and well-being benefits that the visitors expected to receive from visits were perceived to be a major personal motivation in the choice to visit Alberta protected areas. The most important motivation factors identified by respondents were psychological and emotional well-being (89.1% of visitors ranked this important), social well-being (88.3%), physical well-being (80.3%), and environmental well-being …

Female Breakfast Skippers Display A Disrupted Cortisol Rhythm And Levated Blood Pressure, Megan Witbracht, Nancy L. Keim, Shavawn Forester, Adrianne Widaman, Kevin D. Laugero

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Chronic stress and over-activity in the hypothalamic–pituitary–adrenal (HPA) axis may link breakfast skipping and poor cardiometabolic health. Missing the first major meal of the day in rodents prolongs elevated circulating corticosterone at a time when it's normally decreasing. To extend these findings to humans, we hypothesized that habitual breakfast skippers would display a similar pattern of circulating cortisol and alterations in meal and stress-induced cortisol reactions. Normal weight to obese women aged 18–45 years old who were strictly defined as either breakfast skippers (n = 30) or breakfast eaters (n = 35) were invited to participate in our …

Whose Urban Forest? The Political Ecology Of Foraging Urban Nontimber Forest Products, Patrick T. Hurley, Marla R. Emery, Rebecca J. Mclain, Melissa R. Poe, Brain Grabbatin, Cari L. Goetcheus

Institute for Sustainable Solutions Publications and Presentations

Drawing on case studies of foraging in Philadelphia, Pennsylvania and Mt. Pleasant, South Carolina, we point to foraging landscapes and practices within diverse urban forest spaces. We examine these spaces in relation to U.S. conservation and development processes and the effects of management and governance on species valued by foragers. These case studies reveal the everyday landscapes of urban foraging and suggest that ideas about what constitutes the suite of appropriate human-environment interactions in the sustainable city are contested and accommodated in diverse ways.

Using Storm-Watersheds And A Multi-Criteria Decision Model For Biodiversity Conservation In An Urban Environment, Christina M. Chiappetta

Legacy Theses & Dissertations (2009 - 2024)

Many planning and land use decisions in New York State are controlled at the local (town or municipal) level, not an optimal scale for planning and implementing resource conservation management. Watershed boundaries provide a more ecologically meaningful scale for conservation, because they capture a full range of natural ecosystem processes that span political boundaries. However, defining an urban watershed is complicated by stormwater infrastructure, so standard topographic watershed boundaries may be inadequate for urban resource conservation even when applied at the watershed scale. Storm-watersheds distort both municipal and watershed boundaries, because the flows are redirected in ways that are often …

Learning Love From A Tiger: Approaches To Nature In An American Buddhist Monastery, Daniel S. Capper

Faculty Publications

In current debates about Buddhist approaches to the non-human natural world, studies describe Buddhism variously as anthropocentric, biocentric or ecocentric. These perspectives derive for the most part from examinations of philosophical and normative aspects of the tradition without much attention to moments when embodied practice diverges from religious ideals. Responding to the need for narrative thick descriptions of lived Buddhist attitudes toward nature, I ethnographically explore a Vietnamese monastery in the United States. There I find multifaceted Buddhist approaches to nature which sometimes disclose disunity between theory and practice. Philosophically and normatively, this monastery embraces ecocentrism through notions of interconnectedness, …

Failure Of Science, Death Of Nature, H.F. Recher

Research outputs 2014 to 2021

As a people, Australians have lost contact with the world of nature, Risking the collapse of civilization. One factor in the alienation of nature in Australia is the failure of the scientific community to take responsibility for the technology created by the knowledge generated from scientific research. Science has failed to protect Australia's flora and fauna. Scientists must communicate more widely with society, but need to be educated on how to communicate and on their ethical responsibilities to others and other species. Government needs to show leadership in environmental management and nature conservation, while conservationists need to 'invert the paradigm', …

Effects Of Ambient Coarse, Fine, And Ultrafine Particles And Their Biological Constituents On Systemic Biomarkers: A Controlled Human Exposure Study, Ling Liu, Bruce Urch, Raymond Poon, Mieczyslaw Szyszkowicz, Mary Speck, Diane R. Gold, Amanda J. Wheeler, James A. Scott, Jeffrey R. Brook, Peter S. Thorne, Frances S. Silverman

Research outputs 2014 to 2021

Background: Ambient coarse, fine, and ultrafine particles have been associated with mortality and morbidity. Few studies have compared how various particle size fractions affect systemic biomarkers. Objectives: We examined changes of blood and urinary biomarkers following exposures to three particle sizes. Methods: Fifty healthy nonsmoking volunteers, mean age of 28 years, were exposed to coarse (2.5–10 μm; mean, 213 μg/m3) and fine (0.15–2.5 μm; mean, 238 μg/m3) concentrated ambient particles (CAPs), and filtered ambient and/or medical air. Twenty-five participants were exposed to ultrafine CAP (< 0.3 μm; mean, 136 μg/m3) and filtered medical air. Exposures lasted 130 min, separated by ≥ 2 weeks. Blood/urine samples were collected preexposure and 1 hr and 21 hr postexposure to determine blood interleukin-6 and C-reactive protein (inflammation), endothelin-1 and vascular endothelial growth factor (VEGF; vascular mediators), and malondialdehyde (lipid peroxidation); as well as urinary VEGF, 8-hydroxy-deoxy-guanosine (DNA oxidation), and malondialdehyde. Mixed-model regressions assessed pre- and postexposure differences. results: One hour postexposure, for every 100-μg/m3 increase, coarse CAP was associated with increased blood VEGF (2.41 pg/mL; 95% CI: 0.41, 4.40) in models adjusted for O3, fine CAP with increased urinary malondialdehyde in single- (0.31 nmol/mg creatinine; 95% CI: 0.02, 0.60) and two-pollutant models, and ultrafine CAP with increased urinary 8-hydroxydeoxyguanosine in single- (0.69 ng/mg creatinine; 95% CI: 0.09, 1.29) and two-pollutant models, lasting < 21 hr. Endotoxin was significantly associated with biomarker changes similar to those found with CAPs. conclusions: Ambient particles with various sizes/constituents may influence systemic biomarkers differently. Endotoxin in ambient particles may contribute to vascular mediator changes and oxidative stress.

Do Water Buffalo Facilitate Dispersal Of Invasive Alien Tree Species Acacia Nilotica In Bekol Savanna Baluran National Park?, Sutomo

Research outputs 2014 to 2021

Invasion of Acacia nilotica in Baluran National Park, East Java Province, Indonesia, has caused significant loss to savanna cover which is the main natural feature of the park. This study aimed to describe whether water buffalo may play a role in the dispersal of Acacia nilotica seed in Bekol Savanna usinganalysis of buffalo stools/scats, observations and seed experiments. In total there were 30 plots set up around the Bekol Savanna to collect buffalo stools. In addition,A. nilotica pods matured from its trees were collected, as controls. Germination tests were conducted on seeds that were extracted from the collected stools …

Reservoir Area Of Influence And Implications For Fisheries Management, Dustin R. Martin, Christopher J. Chizinski, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Understanding the spatial area that a reservoir draws anglers from, defined as the reservoir’s area of influence, and the potential overlap of that area of influence between reservoirs is important for fishery managers. Our objective was to define the area of influence for reservoirs of the Salt Valley regional fishery in southeastern Nebraska using kernel density estimation. We used angler survey data obtained from in-person interviews at 17 reservoirs during 2009–2012. The area of influence, defined by the 95% kernel density, for reservoirs within the Salt Valley regional fishery varied, indicating that anglers use reservoirs differently across the regional fishery. …

Reservoir Rehabilitations: Seeking The Fountain Of Youth, Mark A. Pegg, Kevin L. Pope, Larkin A. Powell, Kelly C. Turek, Jonathan J. Spurgeon, Nathaniel T. Stewart, Nick P. Hogberg, Mark T. Porath

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Aging of reservoirs alters the functions, and associated services, of these systems through time. The goal of habitat rehabilitation is often to alter the trajectory of the aging process such that the duration of the desired state is prolonged. There are two important characteristics in alteration of the trajectory—the amplitude relative to current state and the subsequent rate of change, or aging—that ultimately determine the duration of extension for the desired state. Rehabilitation processes largely fall into three main categories: fish community manipulation, water quality manipulation, and physical habitat manipulation. We can slow aging of reservoirs through carefully implemented management …

The Global Status Of Freshwater Fish Age Validation Studies And A Prioritization Framework For Further Research, Jonathan J. Spurgeon, Martin J. Hamel, Kevin L. Pope, Mark A. Pegg

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Age information derived from calcified structures is commonly used to estimate recruitment, growth, and mortality for fish populations. Validation of daily or annual marks on age structures is often assumed, presumably due to a lack of general knowledge concerning the status of age validation studies. Therefore, the current status of freshwater fish age validation studies was summarized to show where additional effort is needed, and increase the accessibility of validation studies to researchers. In total, 1351 original peer-reviewed articles were reviewed from freshwater systems that studied age in fish. Periodicity and age validation studies were found for 88 freshwater species …

Experimental Evaluation Of Rainbow Trout Oncorhynchus Mykiss Predation On Longnose Dace Rhinichthys Cataractae, Kelly C. Turek, Mark A. Pegg, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Laboratory and in-stream enclosure experiments were used to determine whether rainbow trout Oncorhynchus mykiss influence survival of longnose dace Rhinichthys cataractae. In the laboratory, adult rainbow trout preyed on longnose dace in 42% of trials and juvenile rainbow trout did not prey on longnose dace during the first 6 h after rainbow trout introduction. Survival of longnose dace did not differ in the presence of adult rainbow trout previously exposed to active prey and those not previously exposed to active prey (x²₁ = 0.28, P = 0.60). In field enclosures, the number of longnose dace decreased at …

Barriers And Bridges To The Integration Of Social–Ecological Resilience And Law, Olivia Odom Green, Ahjond S. Garmestani, Craig R. Allen, Lance H. Gunderson, J.B. Ruhl, Craig A. Arnold, Nicholas A.J. Graham, Barbara Cosens, David G. Angeler, Brian C. Chaffin, C.S. Holling

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

There is a fundamental difference between the ways in which ecologists and lawyers view uncertainty: in the study of ecology, uncertainty provides a catalyst for exploration, whereas uncertainty is antithetical to the rule of law. This issue is particularly troubling in environmental management, where the tensions between law and ecology become apparent. Rather than acknowledge uncertainties in management actions, legal frameworks often force a false sense of certainty in linking cause and effect. While adaptive management has been developed to deal with uncertainty, laws and legal wrangling can be obstacles to implementation. In this article, we recommend resilience-based governance – …

Quantifying The Adaptive Cycle, David G. Angeler, Craig R. Allen, Ahjond S. Garmestani, Lance H. Gunderson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation) in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term …

Across-Ecoregion Analysis Suggests A Hierarchy Of Ecological Filters That Regulate Recruitment Of A Globally Invasive Fish, Przemek G. Bajer, Timothy K. Cross, Joseph D. Lechelt, Christopher J. Chizinski, Michael J. Weber, Peter W. Sorensen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Aim -- Even successful invaders are abundant only in a fraction of locales they inhabit. One of the main challenges in invasion ecology is explaining processes that drive these patterns. We investigated recruitment of a globally invasive fish, common carp (Cyprinus carpio), across three ecoregions to determine the role of environmental characteristics, predatory communities and propagule pressure on the invasion process at coarse and fine spatial scales.

Location -- Lakes across Northern Forest, Temperate Forest and Great Plains ecoregions of North America.

Methods -- We used data from 567 lakes to model presence or absence of carp recruitment …

Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments, Daniel D. Snow, David A. Cassada, Shannon L. Bartelt-Hunt, Xu Li, Matteo D'Alessio, Rachel Levine, Yun Zhang, J. Brett Sallach

Nebraska Water Center: Faculty Publications

A total of 43 papers published in 2014 were reviewed ranging from detailed descriptions of analytical methods, to fate and occurrence studies, to measuring and predicting biological effects for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, natural and synthetics steroids, and antibiotic resistance genes in agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Occurrence and Fate, Antibiotic Resistance Genes, and Risk Assessment.

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 …

Sustainability Lesson Evaluation, Alison Stemczynski

Honors Projects

No abstract provided.

Ph Dependent Antibiotic Resistance Of An Alkaliphilic, Halotolerant Bacterium Isolated From Soap Lake, Washington, Tiffany Charlynn Edwards

Masters Theses

"Soap Lake, located in Washington State, is a meromictic, soda lake. Many bacterial isolates retrieved from Soap Lake have been noted to possess resistance to multiple antibiotics. A likely explanation for the wide range of antibacterial resistance exhibited by these strains is due to the impact of high alkalinity on the antibiotics themselves and not due to the presence of antibiotic resistance genes. The aim of our study was to determine if select antibiotics are effective against Halomonas eurialkalitoleranis, a bacterium capable of growth over a wide range of neutral to alkaline pH values, to investigate the influence of alkalinity …

A Composite Spatial Model Incorporating Groundwater Vulnerability And Environmental Disturbance To Guide Land Management, Johanna L. Kovarik

USF Tampa Graduate Theses and Dissertations

Research has long recognized and studied the dynamics of groundwater processes. More recently, groundwater dependent ecosystems (GDEs) are being recognized for their diversity and vulnerability to anthropogenic impact. Groundwater in karst landscapes presents a distinctive situation where flow through the subsurface often moves rapidly on the scale of days and weeks as opposed to years or millennia in other systems. This distinctive situation of karst systems and their vulnerability to human impacts necessitate an integrated and multifaceted approach for the management of these important resources. However, development of such an approach is complicated by the difficulty of obtaining detailed data …

What's In A Name?, Rosalyn Lapier

Environmental Studies Faculty Publications

How do Native people select names for people? This article explores the traditional ecological knowledge of the Blackfeet, religious and world view, and naming.