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Evidence Of An Active Enso And Pdq During The Mid-Holocene From A Costa Rican Speleothem, April D. Azouz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Although the El Nino/Southern Oscillation (ENSO) is the most important source of inter-annual climate variability in the tropics, its Holocene history is poorly understood, particularly in Central America. A high resolution (-3.8 years/sample) paleoclimate record of Central American rainfall variability has been reconstructed from a U /Th-dated stalagmite (7890 to 6490 yrs B.P.) from Costa Rica to constrain the onset and variability of ENSO throughout the Holocene, and to determine its role in generating regional climate anomalies. I suggest drier conditions, forced by El Nino, are represented by higher 5180 values, and are correlative with higher 513C values, indicating that …

Odonates At The Clark County Wetlands Nature Preserve: A Look At Habitat And Relative Abundance, Erin Jolley

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study is to identify the various species, relative abundance and habitat of dragonfly and damselfly larvae at the Clark County Wetlands Park Nature Preserve (WPNP). An accurate assessment of these insects can be useful in interpreting potential indications of environmental problems at the Wetlands. From this data, necessary improvements can be made to the dragonfly habitat as well as the habitat of other surrounding organisms. Habitat identification is considered especially important because it is "structured by instream and surrounding topographical features, and is a major determinant of aquatic community potential" (Southwood, 1977). For purposes of this …

The Contribution Of Environmental Variables On Small Mammal Species Richness And Relative Abundance In Eastern Nevada, Stephanie Harris

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study is to determine how four environmental variables: elevation, latitude, soil type, and vegetation impact the relative abundance of Peromyscus maniculatus and the species richness of small mammal populations in Eastern Nevada. In order to complete this study, a survey of small mammals was completed in the following 8 Eastern Nevada valleys: Delamar, Dry Lake, Dry Lake- Muleshoe,Cave, Lake, Snake, Spring, White River. In each valley, transects of Sherman live traps will be set up for 3 consecutive nights (O'Farrell et al 1977). Data on elevation, latitude, soil type, and vegetation were taken at each trap …

Anaerobic Digester Use In Dairy Farms In The United States, Shaun Elsasser

UNLV Theses, Dissertations, Professional Papers, and Capstones

Anaerobic digestion is a highly efficient process, trapping the methane gas from cow manure and processing it into energy. The steep initial capital costs make anaerobic digesters short-term liabilities, but the long-term benefits far outweigh the long-term costs. An anaerobic digester unit will begin to show a profit after approximately five years of operation. During the lifetime of the unit, estimated at 15 years, the digester will have produced about $ 1,000,000 in profits for the dairy farm, while also providing invaluable benefits to society as a whole.

The Fate And Transport Of Nitrogen (N) And The Effect Of Emergent Plants On Natural Treatment Of N-Species At Las Vegas Wash, Nevada, Tanju Kiriscioglu

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study is to analyze the effect of emergent plant communities at Las Vegas Wash (the System) using a system dynamics modeling approach. Understanding the dynamics of nitrogen (N —major polluting nutrient in the Wash) that enters the System is important because it occasionally causes algal blooms, choking Lake Mead through excessive eutrophication. Emergent plant communities are an integral part of wetland ecosystems and they play a crucial role in natural treatment of nutrients. This study is intended to test this hypothesis.

The study makes use of Wash data from reliable sources (Las Vegas Valley Water District, …

Population Trends Of Wintering Bald Eagles (Haliaeetus Leucocephalus) At The Lake Mead National Recreation Area, Nevada, Deanna Morrell

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to look at population trends of wintering bald eagles (Haliaeetus leucocephalus) at the Lake Mead National Recreation Area, Nevada from 1991 to 2006. Bald eagles were counted on January 5, 2006 along the entire shoreline of Lake Mead and Lake Mohave. This study focused on two questions: (1) how has the population changed over time? (2) How has the proportion of juvenile eagles to adult eagles changed over time? Question one was supported with the number of bald eagles significantly increasing (r=0.76, p=0.002). Question two was supported as the proportion of juveniles to adults …

A Study Of Environmental Justice In Relation To Air Pollution And Income, Christian A. Malveaux

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this paper is come to a conclusion on whether or not air pollution and income levels are connected. There is an ongoing pollution problem in Las Vegas. The question that will be attempted to answer in this is paper is: Is there a difference in the amount of air pollution in affluent parts of the Las Vegas Valley and the less affluent parts of the valley? Information and data regarding air pollution is gathered from the Clark County website and other literature. Information on income levels is gathered from journals and literature pertinent to the subject and …