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Full-Text Articles in Life Sciences

Plant Genotype, Not Nutrients, Shape Aphid Population Dynamics, Heather E. Tran, Lara Souza, Nathan J. Sanders, Aimee T. Classen Dec 2011

Plant Genotype, Not Nutrients, Shape Aphid Population Dynamics, Heather E. Tran, Lara Souza, Nathan J. Sanders, Aimee T. Classen

Chancellor’s Honors Program Projects

No abstract provided.


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 …


Zoos As Experiment Environments: Biology Of Larval And Adult Mosquitoes (Diptera: Culicidae), Holly Tuten Aug 2011

Zoos As Experiment Environments: Biology Of Larval And Adult Mosquitoes (Diptera: Culicidae), Holly Tuten

All Dissertations

Zoos are a unique environment where humans and animals are in close daily contact, potential mosquito habitats exist, exotic plants and animals are introduced regularly, and wild animals roam. Studies of mosquito behaviors in zoos will lead to a better understanding, both within and outside zoos, of disease transmission routes and mosquito biology. To investigate whether the unique assemblage of habitats in zoos affects mosquito behavior, I sampled larvae and adults in the Greenville Zoo and the Riverbanks Zoo, South Carolina, USA, from March 2008 to January 2011. The objectives of my study were to investigate mosquito oviposition behavior, blood-host …


Old Father Hudson: The Three Stages Of Environmental Activism In The Hudson River Valley, Gregory P. Cannillo Jun 2011

Old Father Hudson: The Three Stages Of Environmental Activism In The Hudson River Valley, Gregory P. Cannillo

Honors Theses

Consequences of development have threatened the health of the Hudson River for decades. These have included the prospect of destroying scenic value of the Hudson River Valley with the a hydroelectric power plant on Storm King Mountain, as well as the pollution of the river itself by a variety of industrial sources. Since the 1960s, a long lineage of environmental activism in the Hudson River Valley has emerged to address those issues. The example of the Hudson River supplies an excellent case study of how environmental issues began to be addressed in the later half of the 20th century. I …


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 …


Sponges Of The Caribbean: Linking Sponge Morphology And Associated Bacterial Communities, Ericka Ann Poppell May 2011

Sponges Of The Caribbean: Linking Sponge Morphology And Associated Bacterial Communities, Ericka Ann Poppell

Master's Theses

The ecological and evolutionary relationship between sponges and their symbiotic microflora remains poorly understood, which limits our ability to understand broad scale patterns in benthic-pelagic coupling on coral reefs. Previous research classified sponges into two different categories of sponge microbial associations: High Microbial Abundance (HMA) and Low Microbial Abundance (LMA) sponges. Choanocyte chamber morphology and density was characterized in representatives of HMA and LMA sponges using scanning electron microscopy from freeze-fractured tissue. Denaturing Gradient Gel Elextrophoresis was used to examine taxonomic differences among the bacterial communities present in a variety of tropical sponges. The results supported the hypothesis that choanocyte …


Epigeic Spider (Araneae) Diversity And Habitat Distributions In Kings Mountain National Military Park, South Carolina, Sarah Stellwagen May 2011

Epigeic Spider (Araneae) Diversity And Habitat Distributions In Kings Mountain National Military Park, South Carolina, Sarah Stellwagen

All Theses

This study examined the epigeic spider fauna in Kings Mountain National Military Park. The aim of this study is to make this information available to park management for use in the preservation of natural resources. Pitfall trapping was conducted monthly for one year in three distinct habitats: riparian, forest, and ridge-top. The study was conducted from August 2009 to July 2010. One hundred twenty samples were collected in each site. Overall, 289 adult spiders comprising 66 species were collected in the riparian habitat, 345 adult comprising 57 species were found in the forest habitat, and 240 adults comprising 47 species …


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 …


Interception In Open-Grown Douglas-Fir (Pseudotsuga Menziesii) Urban Canopy, Mitchell Bixby Jan 2011

Interception In Open-Grown Douglas-Fir (Pseudotsuga Menziesii) Urban Canopy, Mitchell Bixby

Dissertations and Theses

I hypothesized that Douglas-fir trees (Pseudotsuga menziesii) standing apart from other trees ('open-grown') will intercept more rainfall than Douglas-fir trees standing near other trees ('closed-canopy'). Open-grown trees differ structurally and are more common in urban settings, yet have been infrequently studied. Existing literature, based primarily on closed-canopy trees, suggests Douglas-fir trees in Pacific Northwest forests intercept approximately 25% of rainfall annually. Because open-grown trees have more vertical leaf area than individual trees in closed-canopy forests, I expected to find higher interception by open-grown trees.

I collected throughfall under four open-grown Douglas-firs using six static collectors ('buckets') per tree, …


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 …


Soil Moisture, Fire, And Tree Community Structure, William Patrick White Jan 2011

Soil Moisture, Fire, And Tree Community Structure, William Patrick White

Browse all Theses and Dissertations

My study was conducted to understand tree community structure and how soil moisture and fire frequency influence them. Eighteen plots were placed in the Edge of Appalachia Nature Preserve of unglaciated southern Ohio: nine within a prescribed burn site and nine control sites outside the burn. Sites were stratified in triplicate across GIS-derived integrated soil moisture index (IMI) classes. Burning was done in 1996. Overstory species dbh and sapling species were sampled 1997, 2001, and 2008. Overstory stems were located in 2009 using range finders. Stem locations were loaded into GIS using novel techniques to quantify individual stem IMI values. …