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Full-Text Articles in Physical Sciences and Mathematics

River Restoration: Institutions, Boundaries, And Social Ecological Dynamics, Eileen Sylvan Johnson Dec 2015

River Restoration: Institutions, Boundaries, And Social Ecological Dynamics, Eileen Sylvan Johnson

Electronic Theses and Dissertations

This human dimensions research, consisting of three manuscripts, explores the social and ecological dimensions of river restoration through an examination of the restoration trajectories of the Androscoggin, an impaired system, and the Kennebec, a restored system. Manuscript one examines the influence of biophysical and community attributes and institutional rules on policy stakeholders goals and actions within the two watersheds. For manuscripts one and two, we conducted semi-structured interviews with key informants, assembled documents pertaining to restoration actions, and conducted participant observation at stakeholder meetings. We qualitatively analyzed transcripts and documents. Results suggest that policy stakeholders’ understandings of biophysical and community …


Biogeography And Conservation Of Tidal Marsh Bird Communities Across A Changing Landscape, Maureen D. Correll Dec 2015

Biogeography And Conservation Of Tidal Marsh Bird Communities Across A Changing Landscape, Maureen D. Correll

Electronic Theses and Dissertations

Given the current mass extinction crisis and continued fragmentation of resources worldwide, the outlook is dire for global biodiversity. Rising global temperature, sea levels, and storm frequency all create environmental conditions that can drive change in species abundance and distribution across a landscape. Those species reliant upon a single type of habitat and resource for survival, termed “specialists”, are particularly vulnerable to change due to their inability to utilize a variety of resources well. As a result, specialism is now considered one of the dominant factors determining extinction of species. In this dissertation I explore the effects of disturbance on …


Using Kriging, Cokriging, And Gis To Visualize Fe And Mn In Groundwater, Crystal Johnson May 2015

Using Kriging, Cokriging, And Gis To Visualize Fe And Mn In Groundwater, Crystal Johnson

Electronic Theses and Dissertations

For aesthetic, economic, and health-related reasons, allowable concentrations of iron (Fe) and manganese (Mn) found present in drinking water are 0.3 mg/L and 0.05 mg/L, respectively. Water samples taken from private drinking wells in the rural communities within Buncombe County, North Carolina contain amounts of these metals in concentrations higher than the suggested limits. This study focused on bedrock geology, elevation, saprolite thickness, and well depth to determine factors affecting Fe and Mn. Using ArcGIS 10.2, spatial trends in Fe and Mn concentrations ranges were visualized, and estimates of the metal concentrations were interpolated to unmonitored areas. Results from this …


Functional Characterization Of Green Sorption Media And Scaling Of Pilot Studies For Copper Removal In Stormwater Runoff, Cameron Houmann Jan 2015

Functional Characterization Of Green Sorption Media And Scaling Of Pilot Studies For Copper Removal In Stormwater Runoff, Cameron Houmann

Electronic Theses and Dissertations

Green adsorption media with the inclusion of renewable and recycled materials can be applied as a stormwater best management practice for copper removal. A green adsorption media mixture composed of recycled tire chunk, expanded clay aggregate, and coconut coir was physicochemically evaluated for its potential use in an upflow media filter. The results found that the use of the green adsorption media mixture in isolation or the coconut coir with an expanded clay filtration chamber could be an effective and reliable stormwater best management practice for copper removal. A suite of tests were conducted on the media mixture and the …


A Numerical Study Investigating Sensitivity Of Radar Wave Propagation To The Marine Atmospheric Boundary Layer Environment, Nathan E. Lentini Jan 2015

A Numerical Study Investigating Sensitivity Of Radar Wave Propagation To The Marine Atmospheric Boundary Layer Environment, Nathan E. Lentini

Electronic Theses and Dissertations

Radar is a remote sensor that is useful in scientific and military applications. The environment affects the accuracy of radar measurements as well as the predictability of a radar system’s performance. Because of the complexity of the dynamic processes occurring in the marine atmospheric boundary layer (MABL), which includes the lowermost troposphere and ocean surface, the impact of the environment on radar is intricate and difficult to assess. To better understand the relative importance of various aspects of the MABL environment on radar wave propagation, this study evaluates the sensitivity of radar wave propagation to the MABL environment using a …


Population Ecology Of Rocky Mountain Elk In The Black Hills, South Dakota And Wyoming, Benjamin D. Simpson Jan 2015

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.


Drivers Of Agricultural Land Use Change And Management Decisions In The Dakotas: The Influence Of Climate Change And Other Factors, Moses Luri Jan 2015

Drivers Of Agricultural Land Use Change And Management Decisions In The Dakotas: The Influence Of Climate Change And Other Factors, Moses Luri

Electronic Theses and Dissertations

This thesis conducts a general assessment of the: main drivers of land use change; recent and projected land use patterns; and the evolution of agriculture in the Dakotas. Specifically, it determines the main motives of land use change in the Dakotas by investigating individual and joint effects of external drivers of land use change on farm operators’ decisions and also examines recent and projected agricultural land use patterns in the Dakotas. Farm operators’ perceptions about the evolution of agriculture in the Dakotas based on observed changes in their local area were also analyzed. The study region consists of 37 counties …


Climate Driven Changes To Malaria Transmission Patterns In Ethiopian Highlands, Amir Said Siraj Jan 2015

Climate Driven Changes To Malaria Transmission Patterns In Ethiopian Highlands, Amir Said Siraj

Electronic Theses and Dissertations

In the highlands of East Africa, the most populated regions in Africa, temperature is assumed to be intimately connected to the patterns of malaria both in time and space. A large section of the Ethiopian population in this region has historically been shielded from the disease mainly due to the altitudes in the highland regions that have remained free of the disease. However, the region has also seen a large part of its population being affected by malaria in epidemic outbreaks that seem to follow climatic anomalies, especially those of inter-annual increases in temperature. This project examines the inter-annual variability …


Economic And Traffic Impacts Following The Installation Of New Bicycle Facilities: A Denver Case Study, Stephen Antonio Rijo Jan 2015

Economic And Traffic Impacts Following The Installation Of New Bicycle Facilities: A Denver Case Study, Stephen Antonio Rijo

Electronic Theses and Dissertations

America is currently experiencing a unique departure from the historical vehicle miles traveled (VMT) trend, often referred to as "peak travel." Decreasing VMT numbers suggest that the US is currently experiencing an unprecedented change in the way individuals utilize transportation systems. The following research calls on a need to understand the importance of improving alternative transportation infrastructure, namely cycling facilities, and how this impacts local businesses and their communities. This research informs the overarching question, "What are the economic and traffic impacts of cycling facilities?" A mixed methods analysis of retail sales tax, traffic count, and RTD transit access data …


Phytoremediation Of Metal Contamination Using Salix (Willows), Gordon J. Kersten Jan 2015

Phytoremediation Of Metal Contamination Using Salix (Willows), Gordon J. Kersten

Electronic Theses and Dissertations

Abandoned hardrock mines and the resulting Acid Mine Drainage (AMD) are a source of vast, environmental degradation that are toxic threats to plants, animals, and humans. Cadmium (Cd) and lead (Pb) are metal contaminants often found in AMD. In my mine outwash water samples, cadmium and lead concentrations were 19 and 160 times greater than concentrations in control waterways, and 300 and 40 times greater than EPA Aquatic Life Use water quality standards, respectively. I tested the phytoremediation characteristics of three montane willows native to the Rocky Mountains: Salix drummondiana, S. monticola, and S. planifolia. I tested …


When Wells Run Dry: Water And Tourism Along The Western Coast Of Nicaragua, Gary Thomas Lavanchy Jan 2015

When Wells Run Dry: Water And Tourism Along The Western Coast Of Nicaragua, Gary Thomas Lavanchy

Electronic Theses and Dissertations

This dissertation uses a political ecology approach to examine the relationship between tourism development and groundwater in southwest Nicaragua. Tourism in Nicaragua is a booming industry bolstered by ‘unspoiled’ natural beauty, low crime rates, and government incentives. This growth has led to increased infrastructure, revenue, and employment opportunities for many local communities along the Pacific coast. Not surprisingly, it has also brought concomitant issues of deeper poverty, widening gaps between rich and poor, and competition over natural resources. Adequate provisions of freshwater are necessary to sustain the production and reproduction of tourism; however, it remains uncertain if groundwater supplies can …


Development Of An Automated Method For Identification Of Wet And Dry Channel Segments Using Lidar Data And Fuzzy Logic Cluster Analysis, Chris Rowney Jan 2015

Development Of An Automated Method For Identification Of Wet And Dry Channel Segments Using Lidar Data And Fuzzy Logic Cluster Analysis, Chris Rowney

Electronic Theses and Dissertations

Research into the use of LiDAR data for purposes other than simple topographic elevation determination, such as urban land cover classification and the identification of forest biomass, has become prominent in recent years. In many cases, alternative analysis methodologies conducted using airborne LiDAR data are possible because the raw data collected during a survey can include information other than the classically used elevation and coordinate points, the X, Y, and Z of the plane. In particular, intensity return values for each point in a LiDAR grid have been found to provide a useful data set for wet and dry channel …


The Effects Of Chanellization And Channel Restoration On Aquatic Habitat And Biota Of The Pecos River, New Mexico, Darrel J. Mecham Jan 2015

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 …


An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Bronc Mcmurtry Jan 2015

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 …