Matching Items (5)
Filtering by

Clear all filters

151709-Thumbnail Image.png
Description
Modified and artificial water sources can be used as a management tool for game and non-game wildlife species. State, federal, and private agencies allocate significant resources to install and maintain artificial water sources (AWS) annually. Capture mark recapture methods were used to sample small mammal communities in the vicinity of

Modified and artificial water sources can be used as a management tool for game and non-game wildlife species. State, federal, and private agencies allocate significant resources to install and maintain artificial water sources (AWS) annually. Capture mark recapture methods were used to sample small mammal communities in the vicinity of five AWS and five paired control sites (treatments) in the surrounding Sonoran desert from October 2011 to May 2012. I measured plant species richness, density, and percent cover in the spring of 2012. A Multi-response Permutation Procedure was used to identify differences in small mammal community abundance, biomass, and species richness by season and treatment. I used Principle Component Analysis to reduce 11 habitat characteristics to five habitat factors. I related rodent occurrence to habitat characteristics using multiple and logistic regression. A total of 370 individual mammals representing three genera and eight species of rodents were captured across 4800 trap nights. Desert pocket mouse (Chaetodipus penicillatus) was the most common species in both seasons and treatments. Whereas rodent community abundance, biomass, and richness were similar between seasons, community variables of AWS were greater than CS. Rodent diversity was similar between treatments. Desert pocket mouse abundance and biomass were twice as high at AWS when compared to controls. Biomass of white-throated woodrat (Neotoma albigula) was five times greater at AWS. Habitat characteristics were similar between treatments. Neither presence of water nor distance to water explained substantial habitat variation. Occurrence of rodent species was associated with habitat characteristics. Desert rodent communities are adapted for arid environments (i.e. Heteromyids) and are not dependent on "free water". Higher abundances of desert pocket mouse at AWS were most likely related to increased disturbance and debris and not the presence of water. The results of this study and previous studies suggest that more investigation is needed and that short term studies may not be able to detect interactions (if any) between AWS and desert small mammal communities.
ContributorsSwitalski, Aaron (Author) / Bateman, Heather L (Thesis advisor) / Miller, William (Committee member) / Alford, Eddie (Committee member) / Arizona State University (Publisher)
Created2013
151662-Thumbnail Image.png
Description
Livestock-grazing, in particular cattle grazing, is a common use of public and private lands in western North America. As a result, the effects of grazing on both plants and animals are widely studied. Few studies, however, look directly at the long-term effects that cattle grazing may have on a particular

Livestock-grazing, in particular cattle grazing, is a common use of public and private lands in western North America. As a result, the effects of grazing on both plants and animals are widely studied. Few studies, however, look directly at the long-term effects that cattle grazing may have on a particular species. The goal of this experiment was to continue research begun in 1988, to determine if the effects of cattle grazing are still seen in the age structure of two populations of saguaros (Carnegiea gigantea [Engelm.] Britton & Rose) at Saguaro National Park - Rincon Mountain District (SNP-RMD). The null hypothesis stated that enough time has elapsed since the cessation of grazing, and there is no difference in the age distribution of the saguaros of the two populations. The study area was comprised of a former fence line where grazing ceased on the western side of the fence in 1958 and the eastern side in 1978. Belt transects were laid on each side of the fence line and height was measured for each saguaro encountered in a transect. Approximate age of the individual was then calculated using an age-height correlation for SNP-RMD. Individuals were then placed into age classes of 10 year increments and a Log-Likelihood test was performed. The resulting calculated P value of 0.12 meant the null hypothesis was not rejected and there was no statistical difference between the age structure of the two populations. After 34 and 54 years rest from grazing, the negative effects of cattle grazing on the retention and recruitment of saguaro seedlings have ended, and replenishment of the populations is now dependent upon factors such as temperature and precipitation. Other factors such as climate change, increasing fire frequency, encroachment by invasive species, and poaching are sources of concern and increased mortality for these and other saguaros.
ContributorsKrone, Elizabeth AnnMarie Stewart (Author) / Alford, Eddie (Thesis advisor) / Brady, Ward (Committee member) / Green, Douglas (Committee member) / Arizona State University (Publisher)
Created2013
151428-Thumbnail Image.png
Description
Mycorrhizal fungi form symbiotic relationships with plant roots, increasing nutrient and water availability to plants and improving soil stability. Mechanical disturbance of soil has been found to reduce mycorrhizal inoculum in soils, but findings have been inconsistent. To examine the impact of restoration practices on riparian mycorrhizal inoculum potential, soil

Mycorrhizal fungi form symbiotic relationships with plant roots, increasing nutrient and water availability to plants and improving soil stability. Mechanical disturbance of soil has been found to reduce mycorrhizal inoculum in soils, but findings have been inconsistent. To examine the impact of restoration practices on riparian mycorrhizal inoculum potential, soil samples were collected at the Tres Rios Ecosystem Restoration and Flood Control Project located at the confluence of the Salt, Gila, and Agua Fria rivers in central Arizona. The project involved the mechanical removal of invasive Tamarix spp.( tamarisk, salt cedar) and grading prior to revegetation. Soil samples were collected from three stages of restoration: pre-restoration, soil banks with chipped vegetation, and in areas that had been graded in preparation for revegetation. Bioassay plants were grown in the soil samples and roots analyzed for arbuscular mycorrhizal (AM) and ectomycorrhizal (EM) infection percentages. Vegetations measurements were also taken for woody vegetation at the site. The mean number of AM and EM fungal propagules did not differ between the three treatment area, but inoculum levels did differ between AM and EM fungi with AM fungal propagules detected at moderate levels and EM fungi at very low levels. These differences may have been related to availability of host plants since AM fungi form associations with a variety of desert riparian forbs and grasses and EM fungi only form associations with Populus spp. and Salix spp. which were present at the site but at low density and canopy cover. Prior studies have also found that EM fungi may be more affected by tamarisk invasions than AM fungi. Our results were similar to other restoration projects for AM fungi suggesting that it may not be necessary to add AM fungi to soil prior to planting native vegetation because of the moderate presence of AM fungi even in soils dominated by tamarisk and exposed to soil disturbance during the restoration process. In contrast when planting trees that form EM associations, it may be beneficial to augment soil with EM fungi collected from riparian areas or to pre-inoculate plants prior to planting.
ContributorsArnold, Susanne (Author) / Stutz, Jean (Thesis advisor) / Alford, Eddie (Committee member) / Green, Douglas (Committee member) / Arizona State University (Publisher)
Created2012
150097-Thumbnail Image.png
Description
Once considered an abundant species in the eastern United States, local populations of red-shouldered hawks, Buteo lineatus, have declined due to habitat destruction. This destruction has created suitable habitat for red-tailed hawks, Buteo jamaicensis, and therefore increased competition between these two raptor species. Since suitable habitat is the main limiting

Once considered an abundant species in the eastern United States, local populations of red-shouldered hawks, Buteo lineatus, have declined due to habitat destruction. This destruction has created suitable habitat for red-tailed hawks, Buteo jamaicensis, and therefore increased competition between these two raptor species. Since suitable habitat is the main limiting factor for raptors, a computer model was created to simulate the effect of habitat loss in central Maryland and the impact of increased competition between the more aggressive red-tailed hawk. These simulations showed urban growth contributed to over a 30% increase in red-tailed hawk habitat as red-shouldered hawk habitat decreased 62.5-70.1% without competition and 71.8-76.3% with competition. However there was no significant difference seen between the rate of available habitat decline for current and predicted development growth.
ContributorsMurillo, Crystal (Author) / Whysong, Gary (Thesis advisor) / Alford, Eddie (Committee member) / Miller, William (Committee member) / Arizona State University (Publisher)
Created2011
136274-Thumbnail Image.png
Description
Civic engagement is often defined as political activism; to be a part of governmental decision making, the practices thereof, and various efforts of participation in voting. However, civic engagement is also known for its role within non-political work, such as community building and development. Because of the former definition many

Civic engagement is often defined as political activism; to be a part of governmental decision making, the practices thereof, and various efforts of participation in voting. However, civic engagement is also known for its role within non-political work, such as community building and development. Because of the former definition many members of our society have a tendency to not embrace the full potential of their community roles. It is always about who is a Republican, who is a Democrat, who looks better, or who has a better name. Now it must be noted that this is not in absolute, not all members of our society work in this thought process, but many still do. If that doesn't come as a surprise to you, then the simplicity of how you can be an engaged member will. As a student attending Arizona State University at the West campus in Phoenix, Arizona, I have chosen to challenge the traditional view of civic engagement and prepare this development plan for the campus community. Having done so, I not only discovered the paths that one can take to be engaged in such matters, but also continued my role as a civil servant.
ContributorsWaldie, Howard William (Author) / Ackroyd, William (Thesis director) / Smith, Sharon (Committee member) / Alvarez Manninen, Bertha (Committee member) / Barrett, The Honors College (Contributor) / School of Social and Behavioral Sciences (Contributor) / School of Humanities, Arts, and Cultural Studies (Contributor)
Created2015-05