Desert Ecology Commons^™

Precipitation And Greenness In Pastoral Lands Of East Turkana, Kenya, Paul Akpejeluh

School of Natural Resources: Dissertations, Theses, and Student Research

Pastoralism has long supported livelihoods and provided essential ecosystem services in landscapes of East Africa. Vegetation productivity is central to the functioning of pastoral systems but may be affected by changes in climate and landuse. Vegetation monitoring is important for understanding the effects of global change in pastoral lands; however, it can be time and resource intensive. Remote sensing provides opportunities for efficient multi-scale monitoring of vegetation and climatic drivers. In this thesis, I explore the utility of satellite and UAV remote sensing for monitoring vegetation and precipitation trends and relationships in the East of Lake Turkana Region of northern …

Resolving The Paradox Of Polyploidy: Underexplored Facets Of Polyploid Plants, Benjamin Gerstner

Biology ETDs

Polyploidy, or whole genome duplication, is a common phenomenon in plants, but the establishment and persistence of mixed-ploidy populations remains a paradox. This dissertation explores factors that contribute to the persistence and establishment of mixed-ploidy populations in nature. The first chapter investigates the role of unreduced gametes in neopolyploid establishment and finds that variability in their formation rate can have a significant impact on polyploid establishment and persistence. The second chapter searches for evidence of soil microbes exhibiting ploidy-specificity, a pre-condition for microbe-mediated niche differentiation, a possible stabilizing mechanism contributing to ploidy coexistence. Finally, the third chapter tests for microbe-mediated …

The Effects Of Big Dune And Lava Dune Sand Composition On The Eggs And Larvae Of Pseudocotalpa Giulianii, Cosset Hernandez Pena, Mandy Mountain, Daniel B. Thompson

Spectra Undergraduate Research Journal

Differences in the composition of aeolian sand at Big Dune and sand at Lava Dune that is mixed with basalt and various minerals may affect water retention and the development of insects that are specialized for living in sand environments. These two dunes, located in Nye County, Nevada, are home to the endemic dune scarab beetle, Pseudocotalpa giulianii (PSGU). The differences in sand type may influence the growth patterns of the eggs and larvae of this beetle species that hatches and develops to an adult within the sand. The purpose of this experiment is to test whether sand composition affects …

Discovering Dune: Essays On Frank Herbert’S Epic Saga., Edited By Dominic J. Nardi And N. Trevor Brierly, G. Connor Salter

Mythlore: A Journal of J.R.R. Tolkien, C.S. Lewis, Charles Williams, and Mythopoeic Literature

G. Connor Salter reviews Discovering Dune: Essays on Frank Herbert’s Epic Saga, edited by Dominic J. Nardi and N. Trevor Brierly, considering its new contributions to studies of Frank Herbert's work. Essays included fit into four categories (Politics and Power, History and Religion, Biology and Ecology, and Philosophy, Choice and Ethics) and range from Herbert's use of ecology in Dune to how game theory may help explain certain characters' apparent ability to see the future. Discovering Dune also includes an appendix which contains the only up-to-date bibliography of Herbert's work (primary and secondary sources).

National Development And The Sustainability Of Mining In The Atacama Desert, Chile, Dakota Soleil Osgood

Capstone Collection

As climate change continues to intensify on a global scale, efforts have been made to implement renewable energies and progressive technologies. These tools are critical in the shift towards a more sustainable practice, and yet analysis of localized impacts from the development of these mechanisms is inadequate. Chile has been and continues to be a leading country in mineral extraction, with an economic history founded in the mining industry. The establishment of mining in Chile as a progressive tool has aided the social and economic development of the nation. Consequences of mining extraction, however, include intensive environmental degradation, human rights …

Establishment Of The Invasive Cactus Moth, Cactoblastis Cactorum (Berg) (Lepidoptera: Pyralidae) In Pakistan: A Potential Threat To Cultivated, Ornamental And Wild Opuntia Spp. (Cactaceae), Muhammad Ather Rafi, Harry Pavulaan, Muhammad Islam, Muhammad Ashfaq, Haseeb Kamran, Walija Fayaz, Gul Naz Parveen, Riffat Sultana, Ahmad Zia, Waqar Ahmed, Qudrat Ullah, Muhammad Qasim, Falak Naz, Nazeer Ahmed, Muhammad Tariq Khan, Muhammad Saeed, Jalal Hayat Khan

The Taxonomic Report of the International Lepidoptera Survey

Subsequent to the significant accomplishment of biological control of Opuntia weeds in Australia, the larvae of the cactus moth, Cactoblastis cactorum (native to parts of South America), were released in many countries for the biological control of native Opuntia species (Simmonds and Bennett, 1966). Inauspiciously, larvae were also released in the Caribbean, where the moth spread naturally and by the human support all over the region (García-Turudi et al., 1971). Its enhanced dissemination rate and the biological potential for invasiveness, suggests that the cactus moth is likely to become an invasive pest of Opuntia in the Southeast United States, Mexico, …

Growth Of Pseudocotalpa Giulianii Larvae In Sand From Different Dune Sources, Cosset Hernandez Pena, Mandy Mountain

Undergraduate Research Symposium Posters

Pseudocotalpa giulianii (PSGU) is an endemic species known to inhabit two sand dunes in Nye County, Nevada: Big Dune Recreational Area and Lava Dune. Differences in sand properties between Big Dune and Lava Dune could impact survival and growth of the larvae of P. giulianii. Use of permitted off-road vehicles (ORV) in Big Dune can impact its habitats and cause disturbances to local populations, including the Giuliani Dune Scarab as ORV activity is correlated with changes in dune vegetation. Lava Dune has no permitted ORV activity, however, differences in sand composition, including eroded basalt, have the potential to influence the …

Extreme, Positive Geomorphic Change In A Historically Degraded Desert River: Implications For Imperiled Fishes, Tansy T. Remiszewski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rivers comprise some of the most unique and biodiverse ecosystems on the planet with their waters supporting both human societies as well as the organisms that make these rivers their home. Large rivers like the Colorado are often highly regulated and diverted in order to support human residence in arid regions like the desert Southwest, and these water diversions often have dramatic, negative impacts on the natural flow regime of the river. These impacts leave large reaches of the river dry, reduce the river’s capacity to transport sediment, cause channel and habitat homogenization, and significantly reduce the amount of suitable …

Life History And Ecology Of The San Emigdio Blue Butterfly (Lepidoptera: Lycaenidae), Gregory R. Ballmer

The Taxonomic Report of the International Lepidoptera Survey

The San Emigdio blue butterfly, Plebulina emigdionis (Grinnell, 1905), occurs in small, scattered colonies in and near the southwestern Mojave Desert of California. Colonies depend on a symbiotic relationship with the ant Formica francoueri (Bolton), and occur only where the ant’s range (primarily in more mesic cis-montane habitats) narrowly overlaps that of the butterfly’s more widely distributed Atriplex larval hosts in more xeric habitats. Colonies of P. emigdionis are often localized around a few host plants and, therefore, sensitive to habitat changes due to anthropocentric causes and environmental stochasticity. The biology, ecology, and status of known colonies of P emigdionis …

An Integral Projection Modeling Approach To Understanding Demographic Effects Of Multispecies Mutualisms, Alexandra Campbell

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Above- And Belowground Responses To Environmental Change In The Northern Chihuahuan Desert, Renée F. Brown

Biology ETDs

Drylands cover 45% of the terrestrial surface and are expanding rapidly due to anthropogenic drivers. Altered precipitation regimes, atmospheric nitrogen deposition, and wildfire will likely have significant consequences in these regions where ecological processes are limited by water and nitrogen. In this dissertation, I explored temporal dynamics of net primary production (NPP) and related above- and belowground processes under several environmental change drivers in the Sevilleta National Wildlife Refuge, central New Mexico, USA. Located in the northern Chihuahuan Desert, this region experiences strong seasonal precipitation patterns driven by the North American Monsoon, historically characterized by frequent small rain events hypothesized …

Discovering Novel Polyextremotolerant Fungi, And Determining Their Ecological Role Within The Biological Soil Crust Consortium, Erin Carr

School of Biological Sciences: Dissertations, Theses, and Student Research

The ecological niche of polyextremotolerant fungi within oligotrophic ecosystems such as biological soil crusts has not yet been determined. These fungi persist in locations where nutrients are depleted while simultaneously surrounded by autotrophic microbes such as algae and cyanobacteria. Yet it has not been shown that they are engaging in any exchange of nutrients the way lichens do. However, there is seemingly no other way for these fungi to obtain vital nutrients, such as carbon or nitrogen, other than from these microbes. Here we have isolated polyextremotolerant fungi from cold desert biological soil crusts which are a microbial biofilm that …

Biodiversity And Global Change In Terrestrial Ecosystems, Timothy J. Ohlert

Biology ETDs

Terrestrial ecosystems are critical to human and ecological processes but many gaps in our knowledge remain regarding how terrestrial plant communities assemble and respond to global change. I used field experiments distributed around the world, including long-term experiments from the Sevilleta National Wildlife Refuge (SNWR) in New Mexico and deserts of the southwestern U.S., to evaluate the consequences of drought and other abiotic stressors on plant communities. Dominant grasses were particularly important for the productivity and structure of grasslands at SNWR. In general, the structure of desert plant communities had high resistance to extreme drought, though grasses and other perennial …

3d Library From Body Size From Unconventional Specimens: A 3d Geometric Morphometrics Approach To Fishes From Ancestral Pueblo Contexts, Jonathan Dombrosky, Thomas F. Turner, Alexandra Harris, Emily Lena Jones

Anthropology Faculty & Staff Publications

Animal body size estimation from zooarchaeological specimens often relies on specific, one-dimensional (i.e., conventional) measures from skeletal elements. Here, we introduce an animal body size estimation technique for archaeological fishes that relies on 3D reference scans and the calculation of centroid size, a standard 3D geometric morphometric proxy measure for organism size. Centroid size-based estimations on whole caudal vertebrae are strongly correlated with a widely accepted measure (i.e., centrum width), but the scalability and flexibility of the centroid size-based approach allows for use on a wide variety of fragmented remains. We use zooarchaeological fish remains (subfamily Ictiobinae) from late pre-Hispanic …

Socio-Economic Factors Of Environmental Problems, Manzura Kamalova, D. Shakenov

Karakalpak Scientific Journal

People consciously and intensively rebuild their nature according to their own needs, creating rural and urban areas in which they live. People care about the quality of life in the context of the unity of nature and culture. Social is a relatively new discipline that deals with urban space and environmental issues. One way to imagine what is beneficial to people is to find out what is economically best for the person. The article examines the economic factors that form the attitude towards social ecology in Kazakhstan. The article concludes that society should cooperate to achieve common things, both for …

Healthy Western Lands: A Proposal For Healthy Rangelands, Wildlife, And Free-Roaming Horses And Burros, James S. Sedinger, Rebekah Stetson

Human–Wildlife Interactions

The Coalition for Healthy Nevada Lands, Wildlife and Free-roaming Horses (CHNL) is dedicated to proper management of free-roaming horses (Equus caballus) and burros (E. asinus) so rangelands are healthy, which benefits wildlife and the horses and burros themselves. The CHNL proposes the rapid reduction of horses and burros on designated public lands to achieve appropriate management levels (AML). After these reductions, the use of fertility control, supplemented with some gathers and adoption of gathered horses, should allow the Bureau of Land Management to economically maintain horse and burro populations at AML. The CHNL believes this approach …

Nonnative Ungulate Impacts On Greater Sage-Grouse Late Brood-Rearing Habitat In The Great Basin, Usa, Mikiah R. Mcginn, Steven L. Petersen, Melissa S. Chelak, Randy T. Larsen, Loreen Allphin, Brock R. Mcmillan, Dennis L. Eggett, Terry A. Messmer

Human–Wildlife Interactions

Domestic livestock grazing is the dominant land use on much of the current range inhabited by greater sage-grouse (Centrocercus urophasianus; sage-grouse) in the western United States. Nonnative feral horses (Equus ferus caballus) also inhabit important sage-grouse seasonal habitats. Overabundant feral horse populations and improper grazing by domestic cattle (Bos taurus) can impact the health of sagebrush (Artemisia spp.) and desert shrub rangeland communities and native wildlife. These impacts to sage-grouse can be exacerbated when they affect late brood-rearing habitat, which provide the forbs and arthropods required to fledge broods. Managers require better information …

Feral Horses, Feral Asses, And Professional Politicians: Broodings From A Beleaguered Biologist, Vernon C. Bleich

Human–Wildlife Interactions

As a member of National Wild Horse and Burro Advisory Board, I gained insight into several aspects of feral equid management that previously had been somewhat cryptic. Foremost in my experience, though, was the dedication and professionalism of the board members with whom I served. During my tenure, the professional approach to management and the frustration faced by employees within the Horse and Burro Program became increasingly apparent. Further came the realization that the effectiveness of the board and program can be improved substantially, if (1) the board is provided the opportunity to rebut or counter incorrect or misleading information …

Energy Content Of Seeds Of Switchgrass (Panicum Virgatum) In The Diet Of Mourning Doves (Zenaida Macroura) In Southeastern New Mexico, John L. Hunt, Matthew E. Grilliot, Troy L. Best, Faith A. Johnson, Tyneshia L. Kilgore, Cade M. Wilkerson

Journal of the Arkansas Academy of Science

Switchgrass (Panicum virgatum) is a common forage plant that grows over much of the United States. It has drawn interest as a possible feedstock for biofuels, is used as forage for livestock, is planted for soil conservation, and is a component of the diet of some species of wildlife. We analyzed the energy content of seeds of switchgrass obtained from the crops of mourning doves (Zenaida macroura) collected from plains-mesa sand-scrub in Lea and Eddy counties, New Mexico. Seeds were removed from crops and dried for 48 hours at 60°C to remove moisture and standardize masses. …

A Stillness In The Desert? Engaging The Public Through An Immersive Exploration Of Southwest Soundscapes, Julian Kilker, Thomas Bjelic

Creative Collaborations

The pandemic highlighted the anthropocentric nature of soundscapes, while the recent popularity of electric cars, quadcopters, and “noise cancellation” earbuds demonstrated how consumer products can rapidly change our awareness of sound. While light pollution is already extensively addressed in scholarly research, popular works such as The End of Night, and public engagement such as The International Dark Sky Association, the complex interplay of sound, natural resources, and public engagement is still emerging, particularly in creative fields.

Two UNLV scholars and artists are collaborating on this project: Julian Kilker, who specializes in visual and emerging technology research, and Tom Bjelic, who …