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The Impact Of Ambrosia Trifida (Giant Ragweed) On Native Prairie Species In An Early Prairie Restoration Project, Krisztian Megyeri Dec 2011

The Impact Of Ambrosia Trifida (Giant Ragweed) On Native Prairie Species In An Early Prairie Restoration Project, Krisztian Megyeri

Senior Honors Theses

As the ecological importance of prairies is becoming more recognized, the number of prairie restoration projects is increasing worldwide. One of the major challenges in restoring any disturbed ecosystem is the successful establishment of native species at the expensive of invasive species. While some weedy species are gradually replaced as other, more desired, species become established, there are invasive species that, due to their level of dominance, may out-compete native species indefinitely. The objectives of this study were 1) to quantify the impact of Ambrosia trifida (giant ragweed) on the plant community of a newsly established prairie, 2) to assess …


Nesting Biology Of Osmia Cornifrons: Implications For Population Management, Matthew Mckinney Dec 2011

Nesting Biology Of Osmia Cornifrons: Implications For Population Management, Matthew Mckinney

Graduate Theses, Dissertations, and Problem Reports

The Japanese hornfaced bee, Osmia cornifrons (Hymenoptera: Megachilidae) is a palearctic mason bee managed for the pollination of early season fruit crops such as apple and blueberry. Since its adoption as a managed pollinator in Japan during the 1940s, a large body of literature has amassed with the goal of enhancing O. cornifrons management practices. This research makes important contributions to that literature in two ways. First, the research describes the in-nest relationship of O. cornifrons and the cleptoparasitic mite pest Chaetodactylus krombeini. Distribution of male and female O. cornifrons and of C. krombeini was determined using linear and non-linear …


Climate And Vegetation Change In The Newberry Mountains, Southern Clark County, Nevada, Ross Joseph Guida Aug 2011

Climate And Vegetation Change In The Newberry Mountains, Southern Clark County, Nevada, Ross Joseph Guida

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ecological studies have shown worldwide that vegetation is being affected by climate change. Species are shifting to new elevations and physiographic positions to adapt to changes in their environment. More specifically, paleoecology studies in the Mojave Desert have shown shifting vegetation patterns in response to past warming and precipitation changes. Recent studies have shown mortality among desert plants related to extended drought and warming. However, few studies have shown how the geographic distribution of Mojave Desert species has changed during this most recent period of warming. This study addresses this gap in the literature by focusing on several plant species …


Evaluating The Effects Of Morrow's Honeysuckle Control On Vertebrate And Vegetation Assemblages, And Small Mammal Foraging Ecology At Fort Necessity National Battlefield, Charnee Lee Rose Aug 2011

Evaluating The Effects Of Morrow's Honeysuckle Control On Vertebrate And Vegetation Assemblages, And Small Mammal Foraging Ecology At Fort Necessity National Battlefield, Charnee Lee Rose

Graduate Theses, Dissertations, and Problem Reports

Exotic, Japanese bush honeysuckles (Lonicera spp.; Caprifoliaceae) are tied to a variety of impacts on wildlife and ecosystems. Morrow's honeysuckle (Lonicera morrowii) has become a persistent invader in eastern North America. We organized a restoration initiative at Fort Necessity National Battlefield (FONE), Pennsylvania, USA from 2004--2010. Concurrently, we studied the consumption of Morrow's honeysuckle fruits by small mammals from October--November 2009 and July--August 2010, and determined habitat variables that affected visitation rate to foraging stations. Areas of FONE were invaded by Morrow's honeysuckle after the land had been cleared for agriculture, and routine mowing ceased in the mid-1980s. Our restoration …


The Spatial Ecology Of Black Groupers (Mycteroperca Bonaci) In The Upper Florida Keys, Veronique Koch Jun 2011

The Spatial Ecology Of Black Groupers (Mycteroperca Bonaci) In The Upper Florida Keys, Veronique Koch

Open Access Theses

Black groupers (Mycteroperca bonaci) are a critical component of coral reef ecosystems as well as South Florida fisheries. It is therefore of great concern that their essential fish habitat has not yet been fully defined. Using an interdisciplinary approach, the ecology of black groupers was characterized in the Upper Florida Keys. The first part of this study utilized acoustic telemetry. Self-contained acoustic receivers were placed in an array around Conch Reef and tracked 16 tagged black groupers for 483 days. Patterns of movement behavior and habitat usage were modeled using presence-absence data. The capture-recapture program MARK was used to estimate …


Changes In Leaf Morphology, Photosynthesis And Nitrogen Content In Two Coastal Shrubs, Elizabeth Kost May 2011

Changes In Leaf Morphology, Photosynthesis And Nitrogen Content In Two Coastal Shrubs, Elizabeth Kost

Theses and Dissertations

It is important to understand mechanisms that facilitate expansion of two common shrubs, Morella cerifera and Baccharis halimifolia in coastal environments. The purpose of my study was to investigate the physiological and structural changes that occur as leaves age. Photosynthesis, incident light, chlorophyll, and leaf C:N ratios were quantified for young, intermediate, and old leaves (distal, central and proximal leaves, respectively). Leaf structural differences were also compared. Leaves did not change morphologically with age. Light decreased with leaf age and during winter months. Photosynthesis showed no seasonal or age related patterns. Chlorophyll increased initially and then declined with age due …


Ecology Of The Rock Rattlesnake, Crotalus Lepidus, In The Northern Chihuahuan Desert, Vicente Mata Silva Jan 2011

Ecology Of The Rock Rattlesnake, Crotalus Lepidus, In The Northern Chihuahuan Desert, Vicente Mata Silva

Open Access Theses & Dissertations

The Rock Rattlesnake, Crotalus lepidus is a small species that is found from southern Arizona, southern New Mexico, and southern Texas, in the U.S., into northern Mexico. To date, little is known about the ecology of this species. Ecological information is becoming desperately needed for supporting the conservation and protection of species living in fragile environments such as the Chihuahuan Desert amid current local and global threats (e.g., habitat destruction and modification, urban development, and climate change). Although rattlesnakes spend a significant amount of time underground while overwintering, little is known about the physiology and behavior of these organisms during …


Development And Testing Of An Unmanned Aircraft System For Environmental Science, Jerald James Brady Jan 2011

Development And Testing Of An Unmanned Aircraft System For Environmental Science, Jerald James Brady

Open Access Theses & Dissertations

For some environmental science applications, Unmanned Aircraft Systems (UASs) are increasingly recognized for their capacity to collect remotely sensed data in a safer, more efficient and effective manner than is permitted with manned aircraft and satellite remote sensing platforms. To date, however, technological, human, and other challenges have constrained adoption of UASs in the environmental sciences. This study developed and tested a new UAS for an archetypical environmental science research group (stakeholder) composed of non-UAS experts. Specifically, this thesis: 1) Assessed the research and operational needs of the stakeholder to determine the optimum UAS platform; 2) Developed an Unmanned Aerial …


Distribution, Growth, And Disturbance Of Catalina Island Rhodoliths, Paul Anthony Tompkins Jan 2011

Distribution, Growth, And Disturbance Of Catalina Island Rhodoliths, Paul Anthony Tompkins

Master's Theses

Rhodoliths are free-living coralline algae (Rhodophyta) that form large beds on the seafloor. Rhodolith beds are globally widespread and biologically diverse shallow marine habitats. Beds are ecologically sensitive, disturbed by humans, and in Europe are protected by law. While rhodolith beds have been found in California waters at Catalina Island, no literature exists regarding their distribution or ecological significance. This study sought to (1) map the distribution and characterize the rhodolith beds around Catalina, (2) determine the seasonal growth rates, and (3) investigate the effect of common sources of disturbance. A systematic search of shallow subtidal (0-40 meters) areas revealed …


The Evolution And Reproductive Ecology Of Oenothera (Onagraceae), Kyra Krakos Jan 2011

The Evolution And Reproductive Ecology Of Oenothera (Onagraceae), Kyra Krakos

All Theses and Dissertations (ETDs)

This dissertation describes the role of pollination in the floral diversification of Oenothera with an integration of both ecological and phylogenetic approaches. Oenothera: Onagraceae) is a model system for studying plant reproductive biology. It provides excellent examples of shifts in reproductive traits such as pollination and breeding system, features that have been important in angiosperm diversification. These systems are evolutionarily labile; they easily shift between different states. These different reproductive traits may shift in a concerted fashion; therefore, a more comprehensive approach to understanding the evolution of these plant systems simultaneously addresses shifts in pollination and breeding system. Using 54 …


Demographic Response Of American Ginseng (Panax Quinquefolius L.) To Climate Change, Sara Souther Jan 2011

Demographic Response Of American Ginseng (Panax Quinquefolius L.) To Climate Change, Sara Souther

Graduate Theses, Dissertations, and Problem Reports

Ecological response to recent climate change has been documented for a multitude of species worldwide. Climate models predict further increases in temperature, as much as 8 times the degree of warming that has already occurred. Given observations of species response to contemporary climate change and the unprecedented degree of warming expected over the next century, climate change will no doubt determine future ecosystem composition and affect global species diversity. In order to prevent loss of biodiversity, it is necessary to understand and accurately project species' response to climate, and to identify species that are vulnerable to climate change driven extinctions. …