Human-environment interactions in aeolian (windblown) systems has focused research on<br/>human’s role in causing and aiding recovery from natural and anthropogenic disturbance. There<br/>is room for improvement in understanding the best methods and considerations for manual<br/>coastal foredune restoration. Furthermore, the extent to which humans play a role in changing the<br/>shape and surface textures of quartz sand grains is poorly understood. The goal of this thesis is<br/>two-fold: 1) quantify the geomorphic effectiveness of a multi-year manually rebuilt foredune and<br/>2) compare the shapes and microtextures on disturbed and undisturbed quartz sand grains. For<br/>the rebuilt foredune, uncrewed aerial systems (UAS) were used to survey the site, collecting<br/>photos to create digital surface models (DSMs). These DSMs were compared at discrete<br/>moments in time to create a sediment budget. Water levels and cross-shore modeling is also<br/>considered to predict the decadal evolution of the site. In the two years since rebuilding, the<br/>foredune has been stable, but not geomorphically resilient. Modeling shows landward foredune<br/>retreat and beach widening. For the quartz grains, t-testing of shape characteristics showed that<br/>there may be differences in the mean circularity between grains from off-highway vehicle and<br/>non-riding areas. Quartz grains from a variety of coastal and inland dunes were imaged using a<br/>scanning electron microscopy to search for evidence of anthropogenically-induced<br/>microtextures. On grains from Oceano Dunes in California, encouraging textures like parallel<br/>striations, grain fracturing, and linear conchoidal fractures provide exploratory evidence of<br/>anthropogenic microtextures. More focused research is recommended to confirm this exploratory<br/>work.
The COVID-19 Pandemic has provided a challenge for educators to create virtual learning materials that are engaging and impactful during times of high stress and isolation. In this creative project, I explore the variety of virtual tools and web applications from Esri by creating a Story Map on the Verde River Watershed. This Story Map is intended for an audience of students in late middle school and early high school but can be a resource to teachers for a wider age range. The integration of interactive technology and virtual tools in educational practices is likely to continue past the immediate circumstances of the COVID-19 pandemic. The purpose of this Story Map is to showcase one of the many uses for geospatial web applications beyond the immediate realm of GIS.
Spatial-Temporal Analysis of Barrett Freshmen 2007-2012: Source Area Analysis and Poisson Regression
Despite a breadth of work investigating the spatiotemporal details of fluid dynamics over bedforms and bedload transport dynamics over flat beds, there remains a relative dearth of investigations into the spatiotemporal details of bedload transport over bedforms and on a sub-bedform scale. To address this, we conducted two sets of flume experiments focused on the two fundamental regions of flow associated with bedforms: flow separation/reattachment on the lee side of the bedform (Chapter 1; backward facing-step) and flow reacceleration up the stoss side of the next bedform (Chapter 2; two-dimensional bedform). Using Laser and Acoustic Doppler Velocimetry to record fluid turbulent events and manual particle tracking of high-speed imagery to record bedload transport dynamics, we identified the existence and importance of “permeable splat events” in the region proximal to flow reattachment.
These coupled turbulent and sediment transport events are integral to the spatiotemporal pattern of bedload transport over bedforms. Splat events are localized, high magnitude, intermittent flow features in which fluid impinges on the bed, infiltrates the top portion of bed, and then exfiltrates in all directions surrounding the point of impingement. This initiates bedload transport in a radial pattern. These turbulent structures are primarily associated with quadrant 1 and 4 turbulent structures (i.e. instantaneous fluid fluctuations in the streamwise direction that bring fluid down into the bed in the case of quadrant 1 events, or up away from the bed in the case of quadrant 4 events) and generate a distinct pattern of bedload transport compared to transport dynamics distal to flow reattachment. Distal to flow reattachment, bedload transport is characterized by relatively unidirectional transport. The dynamics of splat events, specifically their potential for inducing significant magnitudes of cross-stream transport, has important implications for the evolution of bedforms from simple, two dimensional features to complex, three-dimensional features.
New advancements in sonar technology have enabled more detailed quantification of bedload transport on the reach scale, a process paramount to the effective management of rivers with sand or gravel-dominated bed material. However, a practical and scalable field methodology for reliably estimating bedload remains elusive. A popular approach involves calculating transport from the geometry and celerity of migrating bedforms, extracted from time-series of bed elevation profiles (BEPs) acquired using echosounders. Using two sets of repeat multibeam sonar surveys from the Diamond Creek USGS gage station in Grand Canyon National Park with large spatio-temporal resolution and coverage, we compute bedload using three field techniques for acquiring BEPs: repeat multi-, single-, and multiple single-beam sonar. Significant differences in flux arise between repeat multibeam and single beam sonar. Mulitbeam and multiple single beam sonar systems can potentially yield comparable results, but the latter relies on knowledge of bedform geometries and flow that collectively inform optimal beam spacing and sampling rate. These results serve to guide design of optimal sampling, and for comparing transport estimates from different sonar configurations.
General Topics Issue No. 2
Cover Image: Kati Horna, S.NOB #1 cover, 1962, ink on paper. Instituto de Investigaciones Filológicas, Mexico City, Mexico
Published: 2021-04-19
The Journal of Surrealism and the Americas: Vol. 11 No. 2 (2020) - Table of Contents
"Agustín Cárdenas: Sculpting the 'Memory of the Future' by Susan L. Power, p. 98-119.
"Bataillean Surrealism in Mexico: S.NOB Magazine (1962)" by David A.J. Murrieta Flores, p. 120-151.
"Mexican Carnival: Profanations in Luis Buñuel's Films Nazarín and Simón del desierto" by Lars Nowak, p. 152-177.
"Giorgio de Chirico, the First Surrealist in Mexico?" by Carlos Segoviano, p. 178-197?
"Exhibition Review: 'I Paint My Reality: Surrealism in Latin America' by Danielle M. Johnson, p. 198-204.
The Journal of Surrealism and the Americas: Vol. 2 No. 2 (2008) - Table of Contents
“Surrealism and Photography: Introduction” by Wendy Grossman, p. i-iv.
“‘Surrealistic and disturbing’: Timothy O’Sullivan as Seen by Ansel Adams in the 1930s” by Britt Salvesen, p. 162-179.
“‘As if one’s eyelids had been cut away’: Frederick Sommer’s Arizona Landscapes” by Ian Walker, p. 180-208.
“Clarence John Laughlin, Regionalist Surrealist” by Lewis Kachur, p. 209-226.
“A Swimmer Between Two Worlds: Francesca Woodman’s Maps of Interior Space” by Katharine Conley, p. 227-252.
“Remembering Anne D’Harnoncourt” by Valery Oisteanu, p. 253.
“The 1930s: The Making of the ‘New Man’” by Julia Pine, p. 254-258.
“Beyond Bridges: The Cinema of Jean Rouch” by Robert McNab, p. 259-262.
“Review of Kirby Olson, ‘Andrei Codrescu and the Myth of America’” by Éva Forgács, p. 263-267.
“Review of Sally Price, 'Paris Primitive: Jacques Chirac’s Museum on the Quai Branly’” by Kate Duncan, p. 268-272.
The Journal of Surrealism and the Americas: Vol. 3 No. 1 (2009) - Table of Contents
“Surrealism and Post-Colonial Latin America: Introduction” by Susanne Baackmann and David Craven, p. i-xvii.
“‘My Painting is an Act of Decolonization': An Interview with Wifredo Lam by Gerardo Mosquera (1980)” translation by Colleen Kattau and David Craven, p. 1-8.
“Surrealism and National Identity in Mexico: Changing Perceptions, 1940-1968” by Luis M.
Castañeda, p. 9-29.
“Negotiating Surrealism: Carlos Mérida, Mexican Art and the Avant-garde” by Courtney Gilbert, p. 30-50.
“1925 – Montevideo in the Orient: Lautréamont’s Ascent Among the Paris Surrealists” by Gabriel Götz Montua, p. 51-83.
“Paranoia and Hope: The Art of Juan Batlle Planas and its Relationship to the Argentine Technological Imagination of the 1930s and 1940s” by Michael Wellen, p. 84-106.
“Siqueiros and Surrealism?” by Irene Herner, p. 107-127.
“Review of 'Richard Spiteri, Exégèse de Dernier malheur dernière chance de Benjamin Péret'” by John Westbrook, p. 128-131.
“Review of ‘Liliana Porter: Línea de Tiempo’ (Line of Time)” by Arden Decker-Parks, p. 132-134.
“Review of ‘Zurcidos Invisibles: Alan Glass, Construcciones y Pinturas, 1950-2008’” by Susan Aberth, p. 135-138.
“Review of ‘David Hopkins, Dada’s Boys: Masculinity After Duchamp’” by Julian Jason Haladyn, p. 139-140.
“Review of ‘Salvador Dalí: Liquid Desire’” by Ryan Johnston, p. 141-147.