Desert Ecology Commons^™

Machine Learning-Based Spatio-Temporal Modeling Of Climate Dynamics And Desertification In The Sahara–Sahel Region, Stephen M. Tivenan

Theses and Dissertations

Arid climate classifications are threshold-dependent and easily interpretable mappings that are widely used in ecological, agricultural, and climate-related studies. These classifications inform scientific understanding, support policy and land management decisions, and provide an intuitive summary of environmental conditions. Despite their usefulness, traditional arid climate classifications often fail to quantify uncertainty, incorporate spatial context, or account for complex relationships among relevant environmental variables. Existing approaches to uncertainty assessment have largely relied on comparing classifications across multiple datasets or alternative formulas, but these methods generally overlook important spatial dependence and latent structure in the data.

This dissertation develops three machine learning-based statistical …

Some (Im)Material Girls, Living In (Im)Material Worlds, With Seeds, Stars, And Shit, Matthew Weiderspon

Theses and Dissertations

This writing situates material and gestural vocabularies cultivated in my artwork in relation to my lived experience; primarily my rural upbringing in Colorado. Scattered floor dispersals, calling sounds, and bodily movements desire reconsiderations of hope in precarity through a disorientation of place, association, scale, and language.

Genome Wide Epigenetic Analyses Of Araptus Attenuatus, A Bark Beetle, Chitra Seshadri

Theses and Dissertations

Phylogeographic studies have relied on surveying neutral genetic variation in natural populations as a way of gaining better insights into the evolutionary processes shaping present day population demography. Recent emphasis on understanding putative adaptive variation have brought to light the role of epigenetic variation in influencing phenotypes and the mechanisms underlying local adaptation. While much is known about how methylation acts at specific loci to influence known phenotypes, there is little information on the spatial genetic structure of genome-wide patterns of methylation and the extent to which it can extend our understanding of both neutral and putatively adaptive processes. This …

Speed And Resolution In The Age Of Technological Reproducibility, Shawn Taylor

Theses and Dissertations

The rate of acceleration of the biologic and synthetic world has for a while now, been in the process of exponentially speeding up, maxing out servers and landfills, merging with each other, destroying each other. The last prehistoric relics on Earth are absorbing the same oxygen, carbon dioxide and electronic waves in our biosphere as us. A degraded .jpeg enlarged to full screen on a Samsung 4K UHD HU8550 Series Smart TV - 85” Class (84.5” diag.). Within this composite ecology, the ancient limestone of the grand canyon competes with the iMax movie of itself, the production of Mac pros, …

Perennial Atriplex Of Utah And The Northern Deserts, Craig A. Hanson

Theses and Dissertations

Atriplex is a genus in the Chenopodiaceae, the perennial members of which are ecologically important in western North America. Seventeen species and one subspecies of perennial Atriplex occur in Utah and the northern deserts. Three of these species and the subspecies were described by the writer in a recent publication as a result of extensive field work leading to this study. These are A. welshii, A. navajoensis, A. bonnevillensis, and A. cuneata ssp. introgressa. This study is an investigation of the systematics and phytogeography of the perennial Atriplex in Utah and the northern deserts, with emphasis on the A. gardneri …

The Succession Of Vegetation On A Southern Utah Sand Dune, Elias S. Castle

Theses and Dissertations

The sand dunes lying ten miles northwest of Kanab in Kane County, Utah, support a sparse plant cover with four species dominating the vegetation: Psoralea stenostachys, Sophora stenophylla, Oryzopsis hymenoides, and Wyethia scabra var. attenuata. Of these Psoralea and Wyethia are endemic to the dunes or to a limited area which includes the dunes. The pineer species gain a start in the valleys between dunes and occupy the area only until sand covers them or until sand is blown away from their roots. Stabilization of the soils is not permanently in the interdune valleys and the dunes continue to wander. …

The Influence Of Overgrazing On The Density And Number Of Palatable And Unpalatable Desert Forage Plants, John H. Mcguire

Theses and Dissertations

The data for this problem were collected at the Desert Range Experiment Station and on adjoining public domain lands during the summer of 1934, for the purpose of studying the influence of overgrazing on the increase of palatable and unpalatable desert forage plants. A vegetative description of the two areas studied has been prepared and presented.

Effects Of Overgrazing On The Mortality Of Desert Browse Of The Utah West Desert, Charles W. Menzies

Theses and Dissertations

During the summer of 1934 this investigation was conducted to determine the effect of overgrazing on the mortality of desert browse in the vicinity of the Desert Range Branch experiment station. Range lands of western United States have, as a whole been subjected to overgrazing. Utah has about 24 million acres of public acres of public domain that can only be utilized from grazing. An effort has been made to put this area under control. The "Taylor Grazing Act" passed by Congress June 28, 1934 is a big step in the direction of the control of this vast area of …