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Full-Text Articles in Life Sciences

The Distribution And Life Cycle Of Alliaria Petiolata In Lincoln, Nebraska, Caleb Pharris Jul 2011

The Distribution And Life Cycle Of Alliaria Petiolata In Lincoln, Nebraska, Caleb Pharris

Department of Environmental Studies: Undergraduate Student Theses

Alliaria petiolata (Garlic Mustard) is a biennial alien invasive plant species of the Brassicacea family. It is responsible for displacing native plant species throughout North America and its management has proven to be extremely difficult. Recently several populations of Alliaria petiolata have been discovered in southwestern Lincoln, Nebraska. The spread of Alliaria petiolata is a concern for natural resource managers and the general public. Due to the difficulty of its control, Alliaria petiolata is capable of creating monocultures which diminish the aesthetic value of an ecosystem. While most commonly found in the understory of hardwood forests, it is capable of …


Ecotourism In Costa Rica: Environmental Impacts And Management, Emily Mckeone May 2011

Ecotourism In Costa Rica: Environmental Impacts And Management, Emily Mckeone

Department of Environmental Studies: Undergraduate Student Theses

Globally we are witnessing growing environmental destruction, particularly to the natural resource bases of underdeveloped countries. If ecotourism can generate profits for local economies, while protecting and conserving the natural resource base of that community, it could be a strong alternative for numerous countries. Evidence suggests that the ecotourism industry has been expanding at a rapid rate in recent decades (Dasenbrock 2002). It is important to understand the positive and negative ecological impacts of the industry as this rapid growth rate continues.

The main objective of this study is to highlight the strengths and weaknesses of the ecotourism industry in …


An Assessment Of Stable Hydrogen-Isotope Analysis Methods To Assign Geographic Origin To Migratory Red-Tailed Hawks (Buteo Jamaicensis), Carla Marie Ahlschwede May 2011

An Assessment Of Stable Hydrogen-Isotope Analysis Methods To Assign Geographic Origin To Migratory Red-Tailed Hawks (Buteo Jamaicensis), Carla Marie Ahlschwede

Department of Environmental Studies: Undergraduate Student Theses

Stable-hydrogen isotopes are becoming an increasingly popular method of studying migratory birds, though sample preparation methods may affect results. In this study I examined feathers from red-tailed hawks (Buteo jamaicensis) to determine the relationship between measure of δD due to inter-feather variation or drying methods, assessed the accuracy of results by using two birds of known-origin and estimated possible natal origins of migratory red-tailed hawks. Two feathers per individual were taken from 81 wild hawks caught at Hitchcock Nature Center near Crescent IA and from 2 rescued red-tailed hawks, Raptor Recovery Nebraska near Eagle, NE. 119 of the …


River Sediment Sampling Methods- Causeway Building And Removal, Dillon Dittmer Jul 2010

River Sediment Sampling Methods- Causeway Building And Removal, Dillon Dittmer

Department of Environmental Studies: Undergraduate Student Theses

Abstract The Environmental Protection Agency (EPA) and U.S. Fish and Wildlife Service (USFWS) suspect that causeways have a negative impact on river ecology both when installed and when removed. The Nebraska Department of Roads routinely uses causeways as a tool in the construction and repair of bridges. Although research has not been conducted on the impact of causeway building and removal data has been collected about the impact of dams, causeways, etc. on estuaries. This data is considered subjective and authors often cite sampling methods as a source of error. Currently there are no widely used handheld sampling methods that …


Minimun Riparian Buffer Width For Maintaining Water Quality And Habitat Along Stevens Creek, Sammi Bray Apr 2010

Minimun Riparian Buffer Width For Maintaining Water Quality And Habitat Along Stevens Creek, Sammi Bray

Department of Environmental Studies: Undergraduate Student Theses

ABSTRACT Riparian buffer zones are important sites of biodiversity, sediment trapping, pollutant removal, and hydrologic regulation that have significant implications for both people and wildlife. Urbanization’s influence on and need for adequate water quality increases the need for careful planning in regards to riparian areas. Wildlife are key components in the ecosystem functions of riparian zones and require consideration in peri-urban planning as well. This study reviews relevant literature to determine the recommended minimum riparian buffer width for maintaining water quality and habitat along Stevens Creek in Lincoln, Nebraska. Only sources that listed a specific purpose related to water quality …


Herbicides And Amphibian Populations, Zach Shirk Apr 2010

Herbicides And Amphibian Populations, Zach Shirk

Department of Environmental Studies: Undergraduate Student Theses

Amphibians are a unique class of species that are found worldwide except Antarctica and Greenland. They range in size from a few millimeters to over six feet long. Amphibian’s habitats are as various as their size, but one thing in common is that amphibians require an aquatic location to breed. Amphibians live in deserts, mountain prairies, rain forest, wetlands, and almost everywhere in between. Amphibians are an integrated part of most natural ecosystems across the world. Amphibians are a critical part of many food chains; they provide the important link between secondary and tertiary consumers. Amphibians are indicator species in …


Relatin Dissolved Oxygen Concentration To Fish Distribution In Jarecki Lake, Adam Sutton Apr 2010

Relatin Dissolved Oxygen Concentration To Fish Distribution In Jarecki Lake, Adam Sutton

Department of Environmental Studies: Undergraduate Student Theses

Abstract Water temperature and dissolved oxygen (DO) profiles were measured once every month from mid July to mid February in a relatively deep sand-pit lake in southeast Nebraska. These profiles showed depleted DO concentrations below the thermocline during summer stratification indicating areas fish will likely avoid in summer months. Colder temperatures in fall caused complete mixing of the water column allowing fish to inhabit all depths of the lake. An inverse temperature stratification occurred directly below the ice during winter months as ice cover cooled the surface water to below 4 degrees Celsius. Ice cover also blocked air – water …


A Proposed Plan For Managing Eastern Nebraska's Saline Wetlands, Vandhana Rabadinanth Apr 2010

A Proposed Plan For Managing Eastern Nebraska's Saline Wetlands, Vandhana Rabadinanth

Department of Environmental Studies: Undergraduate Student Theses

Abstract Eastern Nebraska’s saline wetlands play a major role in Nebraska’s environmental place in the world. Besides the role of scientific changes being important, education also is essential in the conservation of these wetlands. Through the observation of Salt Creek tiger beetle (Cicindela nevadica lincolniana) and soil electroconductivity, I propose that we need to reform Nebraska’s education system to help schools play a bigger part in environmental issues such as this one. There is a drastic trend in the correlations between Salt Creek tiger beetle populations and wetland degradation. Since many Lincoln residents have a limited knowledge of what is …


Distribution Of Dioecious Eastern Red Cedar (Juniperus Virginiana) Along An Environmental Gradient In Ogallala, Ne., Taylor Sloey Apr 2010

Distribution Of Dioecious Eastern Red Cedar (Juniperus Virginiana) Along An Environmental Gradient In Ogallala, Ne., Taylor Sloey

Department of Environmental Studies: Undergraduate Student Theses

Abstract

The purpose of this research was to study the sex distribution and energy allocation of dioecious Eastern Red Cedars (Juniperus virginiana) along an environmental resource gradient. The trees surveyed were growing in a canyon located at the University of Nebraska’s Cedar Point Biological Research Station in Ogallala, Nebraska. Due to the geography of this canyon, environmental factors necessary for plant growth should vary depending on the tree’s location within the canyon. These factors include water availability, sun exposure, ground slope, and soil nitrogen content, all of which are necessary for carbon acquisition.

Juniperus virginiana is a dioecious conifer. Dioecious …


Changes In Producer Attitudes Towards Windbreaks In Eastern Nebraska, 1983 To 2009, Kim Tomczak Apr 2009

Changes In Producer Attitudes Towards Windbreaks In Eastern Nebraska, 1983 To 2009, Kim Tomczak

Department of Environmental Studies: Undergraduate Student Theses

Abstract Windbreaks are rows of trees or shrubs arranged on the landscape to reduce wind speed. In agricultural landscapes we find them as farmstead windbreaks, livestock windbreaks and field windbreaks. While farmstead and livestock windbreaks are well accepted by the agricultural community, field windbreaks are often viewed differently. A 1982 study of the attitudes of farmers in Eastern Nebraska indicated that many of the producers were around the age of 50 and that they used different types of windbreaks. This study repeated that survey in the same. When compared to data from 1982, farmers today are not educated about the …


A Survery Of Western United States Instream Flow Programs And The Policies That Protect A River's Ecosystem, Kyle Jackson Apr 2009

A Survery Of Western United States Instream Flow Programs And The Policies That Protect A River's Ecosystem, Kyle Jackson

Department of Environmental Studies: Undergraduate Student Theses

The Western United States can best be described as a vast, varying land, with the high plains to the east and the jagged horizons of Rockies to the west. However there is one common trait shared by these states: the lack of water resources. With the continued development of this land, the fact that water is scarce is becoming more real. This issue became more difficult to handle as the public became more aware that many competing uses existed for the finite resource, and those different uses were degrading the natural environments of the surface waters. With this realization instream …