Northern Arizona Research Articles

The Collegiate Wind Competition – Undergraduate Education through Student Competition

The Department of Energy has offered the Collegiate Wind Competition (CWC) since 2014. Penn State and Northern Arizona University are two of four Universities that have fielded teams in each of the competitions since this inaugural year. This paper aims to highlight the ways in which these two programs have integrated the CWC into their curriculum, evolving with time, and also how this competition has tried to meet the needs of providing a diverse, educated workforce prepared for a wide variety of tasks in the wind industry.

Painting Culture, Painting Nature: Stephen Mopope, Oscar Jacobson, and the Development of Indian Art in Oklahoma by Gunlög Fur

Reviewed by: Painting Culture, Painting Nature: Stephen Mopope, Oscar Jacobson, and the Development of Indian Art in Oklahoma by Gunlög Fur Jennifer McLerran Painting Culture, Painting Nature: Stephen Mopope, Oscar Jacobson, and the Development of Indian Art in Oklahoma. By Gunlög Fur. (Norman: University of Oklahoma Press, 2019. Pp. xii, 356. $34.95, ISBN 978-0-8061-6287-4.) In Painting Culture, Painting Nature: Stephen Mopope, Oscar Jacobson, and the Development of Indian Art in Oklahoma, Gunlög Fur presents highly engaging accounts of the lives of two icons of the twentieth-century Native American fine art movement. Swedish American artist and academic Oscar Jacobson and Kiowa painter Stephen Mopope are her subjects. Employing a methodology based in concurrent histories, Fur focuses on the divergences and intersections of Jacobson’s and Mopope’s lives and on the ways the two influenced one another through complex entanglements. In 1927 Jacobson provided Mopope and five other Kiowas with an extraordinary and unparalleled educational and professional opportunity, bringing the young artists to the University of Oklahoma to study easel painting. He also arranged for them to study mural painting with fellow Swedish immigrant artist Olle Nordmark at Fort Sill, Oklahoma. Jacobson’s actions were unprecedented. No other American university had such a program, and it was not until much later in the twentieth century that Native students studied art at American universities in significant numbers. Under Jacobson’s mentorship and promotion, the group of painters who became known as the Kiowa Five gained international recognition and went on to long and successful art careers. What began as a teacher-student relationship that crossed social and cultural boundaries grew into a long-lasting friendship and professional affiliation between Jacobson and Mopope, which contributed significantly to the development of a twentieth-century Native American fine art tradition. Mopope was born on the Oklahoma reservation where his southern plains tribe had been forcibly removed in the 1870s. Jacobson was a Swedish immigrant who was raised in the Swedish American enclave of Lindsborg, [End Page 516] Kansas. After graduating from Yale University, he became an art professor at the University of Oklahoma, where he remained for the rest of his career. Given their backgrounds, Jacobson and Mopope seem like an unlikely pairing. However, as Fur argues, both were members of diasporic communities; and although they experienced dislocation in different ways, each experienced restrictions and loss as a result of their outsider status. Fur argues for the importance of viewing Jacobson’s experience of immigration and Mopope’s experience of dispossession as interdependent and complexly interlinked. While she never loses sight of the greater social inequality Native Americans have experienced relative to Swedish immigrants, she posits that displacement and loss may have served as common points of identification that allowed Jacobson and Mopope to forge and maintain a fruitful alliance. Fur uses published scholarly studies, archival sources, oral histories, and memoirs to reconstruct the lives of Jacobson and Mopope. Mopope’s grand-daughter Vanessa Paukeigope Jennings and Jacobson’s wife, Sophie Brousse Jacobson, who wrote under the pen name Jeanne d’Ucel and completed several unpublished manuscripts on her husband’s life and work, were especially important sources of information. Fur points out that, while scholarship on Swedish immigrants to North America is abundant, histories of interactions between Scandinavian newcomers and American Indians are rare, and such retellings tend to lump all European immigrants together as one indistinguishable group. Fur’s previous scholarship on Swedish immigrant communities in North America and Karen V. Hansen’s Encounter on the Great Plains: Scandinavian Settlers and the Dispossession of Dakota Indians, 1890–1930 (New York, 2013), which Fur cites as influential on her work, are notable exceptions. Historical accounts of Jacobson’s work with the Kiowa artists are numerous. However, Fur provides a richer and more nuanced accounting than her predecessors. Her writing is elegant and engaging, and the narratives she presents are compelling. Anyone with an interest in twentieth-century Native American art will want to read Painting Culture, Painting Nature. Jennifer McLerran Northern Arizona University Copyright © 2020 The Southern Historical Association

Regeneration patterns reveal contraction of ponderosa forests and little upward migration of pinyon-juniper woodlands

A recent severe drought caused widespread mortality of ponderosa pine (Pinus ponderosa) and pinyon pine (Pinus edulis) in forests and woodlands in the southwestern United States. The sustainability of these tree species in the region depends on adequate regeneration and perhaps movement to more climatologically favorable locations. We investigated tree regeneration and species migration along elevation gradients in three community types (pinyon-juniper woodlands, woodland-forest ecotones, and ponderosa pine forests) and three soil parent materials (sedimentary, flow basalt, and volcanic cinder) at 27 sites in northern Arizona. We measured stand characteristics, historic cone production, and density of tree regeneration and small trees. All species produced cones at sites with cinder soil parent material but had little regeneration. Woodlands and woodland-forest ecotones had regeneration of pinyon pine and juniper despite earlier mortality of some mature pinyon trees. Regeneration of ponderosa pine was nearly absent in woodland-forest ecotones, suggesting eventual loss of ponderosa pine and transition to pinyon-juniper woodland. Forests had little regeneration and few small trees of any tree species, indicating little upward migration of pinyon pine and juniper. Occurrence of pinyon pine and juniper regeneration was associated with a suite of biotic and abiotic factors, including a negative relationship with temperature and a positive relationship with precipitation. Regeneration failure of ponderosa pine at woodland-forest ecotone and low-elevation forest sites coupled with limited upward migration of pinyon pine and juniper portends future losses of tree cover as climate continues to warm.

Quantification of Ammonia Emissions With High Spatial Resolution Thermal Infrared Observations From the Hyperspectral Thermal Emission Spectrometer (HyTES) Airborne Instrument

Thermal infrared spectra can provide unique information on atmospheric ammonia enhancements, including those produced by agricultural, industrial, and biomass burning sources. In this work, we develop and test a quantitative ammonia retrieval algorithm using data from the airborne hyperspectral thermal emission spectrometer (HyTES) instrument over diverse targets, including persistent ammonia sources, such as cattle feedlots and a power plant, as well as a small, smoldering wildfire. Although no formal validation was possible due to lack of collocated observations, the HyTES ammonia values over feedlots in the California San Joaquin Valley are shown to be consistent within the estimated retrieval uncertainty of $\sim$ 20%–50% with in situ ammonia values collected over the same facilities during the 2013 DISCOVER-AQ field campaign. HyTES also observed meter-scale thermal hot spots associated with a small wildfire in Northern Arizona, which was determined to coincide with the emission of free ammonia, presumed to originate from the fire. This very localized emission source, not visible from satellite sensors, could be resolved in HyTES imagery. The ammonia enhancement immediately downwind from the smoldering fire, before the free ammonia reacted to form aerosols, was found to be distinguishable from the background with values three to ten times smaller than ammonia enhancements from the power plant and cattle feedlots, respectively. High-resolution detection and quantification of ammonia over nonpersistent sources like wildfires from HyTES shows that it is a powerful tool that can be used to improve regional scale fire emission inventories by accounting for the presence of temporally short ammonia processes.

Investigation, Examination, Control, and Anxiety

This is a special issue on surveilled bodies, with five articles guest edited by Ira Allen, Assistant Professor of Rhetoric, Writing, and Digital Media Studies at Northern Arizona University and Assistant Editor of Screen Bodies. The question here is one of how screens and bodies are brought together through surveillance (visual and otherwise), how surveillance hails the body to attend to it (beckons us to catch a glimpse of here or there) even as it hides itself from the body, working to be noticed yet remaining unnoticed, in order to keep us “on our toes.” In this light, surveillance is not only about investigating, examining, logging, and controlling the body but also about bringing the body into being as a body-to-be-surveilled, about interpolating the body into becoming evermore surveillable in ever-more granular ways.

A microfacies analysis of arid continental carbonates from the Cedar Mesa Sandstone Formation, Utah, USA

AbstractArid continental environments are typically dominated by siliciclastic aeolian, alluvial and fluvial deposits. Despite their common recognition within these environments, carbonate deposits are often overlooked, yet they can provide vital insight into the depositional history, climate and tectonic controls of a sedimentary basin. This work presents a detailed microfacies analysis of the carbonates found within the Cedar Mesa Sandstone Formation of the Western USA. The Cedar Mesa Sandstone Formation is an early Permian, predominantly aeolian succession, exposed across much of the Colorado Plateau of southern Utah and northern Arizona. The formation is dominantly clastic erg deposits, that grade into a mixed carbonate/clastic sedimentary succession interbedded with carbonate and evaporitic units, interpreted to represent sabkha or sabkha‐like deposits. While many authors have worked within the aeolian dominated facies and have proposed various facies schemes for the siliciclastic components, comparatively little attention has been paid to the mixed evaporitic/clastic/carbonate aeolian‐sabkha transition zone. In this work the microfacies of the carbonates present within the Cedar Mesa Sandstone are analysed, in order to: (a) develop a record of, and interpret carbonate components, (b) propose depositional mechanisms and (c) identify evolutionary trends that stand alongside the formation's clastic depositional story. Six microfacies are presented: (MF1) Clastic Influenced Carbonate Wackestone; (MF2) Laminated Carbonate Wackestone/Packstone; (MF3) Microbial Laminated Fenestral Bindstone; (MF4) Rounded Mudclast Wackestone; (MF5) Laminated Bioclastic‐Ostracod‐Carbonate Wackestone and (MF6) Microcrystalline Quartz. The microfacies have been interpreted to document the development of carbonate interdune, lacustrine and continental sabkha environments influenced by localized fault control juxtaposed across a wetting and drying climate cycle and provide useful comparisons for other mixed evaporite/carbonate and clastic sequences.

Is Excellence in the Cards?

Thomas G. McPoil, PT, PhD, FAPTA, is Emeritus Professor of Physical Therapy at Regis University, Denver, Colorado, and Emeritus Regents' Professor of Physical Therapy at Northern Arizona University. He has served as an Adjunct Honorary Professor in the School of Physiotherapy at the University of Queensland, Brisbane, Australia, and currently serves as a consultant to the Physical Therapy Orthotics Clinic at Denver Health Medical Center, Denver, Colorado. Dr. McPoil is known nationally and internationally for his scholarly contributions that have systematically examined foot and ankle function from both scientific and clinical perspectives. Dr. McPoil is an author or coauthor of 130 publications in peer-reviewed journals, coeditor of 2 books, and coauthor of 6 book chapters. His work reaches beyond the profession of physical therapy, as he served on the editorial boards of Foot and Ankle International, the Journal of Foot and Ankle Research, and Research in Sports Medicine and is currently on the editorial boards of the Journal of the American Podiatric Medical Association and The FOOT. Dr McPoil received his PhD in kinesiology with a specialization in biomechanics from University of Illinois at Urbana-Champaign. He holds an MS in physical education with a specialization in athletic training from Louisiana State University and a BA in physical education from the California State University, Sacramento. During his career, he has held faculty appointments at the University of Illinois at Chicago, Northern Arizona University, and Regis University. Dr McPoil's clinical practice has focused on the management of chronic orthopedic foot and ankle disorders for the past 38 years. Dr McPoil is the founding president of the Foot and Ankle Special Interest Group of the Academy of Orthopaedic Physical Therapy. He has served as Vice President of the Academy of Orthopaedic Physical Therapy and as the Treasurer of the Journal of Orthopaedic and Sports Physical Therapy. He has received numerous teaching awards, including APTA's Dorothy E. Baethke & Eleanor J. Carlin Award for Excellence in Academic Teaching and the Academy of Orthopaedic Physical Therapy's James A. Gould Excellence in Teaching Orthopaedic Physical Therapy Award. He is a recipient of a Fulbright Senior Scholar Award, the William J. Stickel Award for Research in Podiatric Medicine, the Academy of Orthopaedic Physical Therapy's Stanley Paris Distinguished Service Award and was elected a Catherine Worthingham Fellow of APTA in 2007.

A true “migrant trap”: Boerhavia (Nyctaginaceae) entanglement as a recurring cause of avian entrapment and mortality

Bird entanglement in plants is a relatively uncommonly documented occurrence, with only a handful of plant species known to recurrently trap birds and cause mortality. Here I describe a large number of bird entanglement events, including 3 confirmed bird deaths, involving Boerhavia torreyana (Torrey's spiderling) in an arid canyon in northern Arizona. Like many species of Boerhavia, B. torreyana possesses sticky rings on its stems that are hypothesized to enhance herbivory defense. I document that these sticky rings also frequently capture birds, and identify 39 separate bird entanglement events involving at least 9 different bird species in a small area where B. torreyana is common. Because B. torreyana is an annual plant that germinates with the arrival of the Southwestern monsoon in mid-summer, it matures and presents an entanglement risk at a time that coincides with the fall bird migration. Small ground-dwelling passerines and insectivores appear to be particularly at risk of being trapped. There are very few known examples of plant species that regularly causes bird entanglement and associated mortality, and the observations presented here document a new case of this phenomenon.

Investigating the Role of Animal Burrows on the Ecology and Distribution of Coccidioides spp. in Arizona Soils.

The lack of knowledge regarding the ecology of Coccidioides spp. makes both modeling the potential for disease outbreaks and predicting the distribution of the organism in the environment challenging. No single ecological parameter explains the biogeography of the pathogen. Previous investigations suggest an association with desert mammals, but these results should be confirmed with modern molecular techniques. Therefore, we used molecular tools to analyze soils associated with animal activity (i.e., burrows) to better define the ecology and biogeography of Coccidioides spp. in Arizona. Soils were collected from locations predicted to have favorable habitat outside of the established endemic regions to better understand the ecological niche of the organism in this state. Our central hypothesis is that soils taken from within animal burrows will have a higher abundance of Coccidioides spp. when compared to soils not directly associated with animal burrows. Our results show that there is a positive relationship with Coccidioides spp. and animal burrows. The organism was detected in two locations in northern Arizona at sites not known previously to harbor the fungus. Moreover, this fungus is able to grow on keratinized tissues (i.e., horse hair). These results provide additional evidence that there is a relationship between Coccidioides spp. and desert animals, which sheds new light on Coccidioides' ecological niche. These results also provide evidence that the geographic range of the organism may be larger than previously thought, and the concept of endemicity should be reevaluated for Coccidioides.

The SPICE project: Production rates of cosmogenic 21Ne, 10Be, and 14C in quartz from the 72 ka SP basalt flow, Arizona, USAu

The SP lava flow is a quartz-, olivine- and pyroxene-bearing basalt with an 40 Ar/ 39 Ar age of 72 ± 4 ka (2σ). The flow is preserved in the desert climate of northern Arizona, USA. Its unweathered appearance and the lack of soil development indicate it has undergone negligible erosion and/or burial, making it an ideal site for direct calibration of cosmogenic nuclide production rates. Cross-calibrated production rates and production rate ratios for cosmogenic 21 Ne, 10 Be, and 14 C have been determined from SP flow quartz. Production rate ratios for 21 Ne/ 10 Be, 21 Ne/ 14 C, and 14 C/ 10 Be are based on the total, local production rates of each cosmogenic nuclide, independent of scaling models, and have error-weighted means (±2σ uncertainty) of 4.44 ± 0.32, 1.43 ± 0.10, and 2.85 ± 0.21, respectively. Error-weighted mean, sea-level, high latitude (SLHL) total reference production rates of 21 Ne, 10 Be, and 14 C are 17.0 ± 1.1, 3.84 ± 0.27, and 11.2 ± 0.6 at/g/yr (2σ), respectively, using time-independent Lal (1991)/Stone (2000) ( St ) scaling factors. St scaled spallogenic 10 Be and 14 C rates are 3.73 ± 0.26 and 9.2 ± 0.6 at/g/yr, respectively. 21 Ne and 10 Be production rates are integrated over the past 72 ka, whereas 14 C production rates are integrated over 25 ka, the time at which SP flow quartz has reached saturation with respect to 14 C. These rates overlap within 2σ uncertainty with other St -scaled production rates in the literature, including the total reference SLHL 21 Ne production rate of Niedermann (2000), which is revised in this paper to 16.8 ± 3.3 at/g/yr (2σ; St scaling) to reflect a recent change in age control at the Sierra Nevada sites. All SLHL production rates are lower if time- dependent Sf , Sa , and Lm scaling factors are used. For example, error-weighted mean, sea-level, high latitude (SLHL) total reference production rates for 10 Be as calculated in the CREp online calculator range from 3.49 ± 0.23 to 3.74 ± 0.25 at/g/yr (2σ), using time-dependent Lm scaling factors. Commonly used SLHL 10 Be and 14 C production rates in the literature were calibrated on surfaces that have been exposed to cosmic rays for less than 20 ka. Between 20 and 50 ka, the geomagnetic field is proposed to have been weaker than it is today. Production rates of cosmogenic nuclides increase during periods of weaker geomagnetic field strength. However, our study finds no measureable difference between St -scaled production rates of cosmogenic 21 Ne and 10 Be over the past 20 ka and St -scaled 21 Ne and 10 Be production rates over the past 72 ka. As such, the study suggests that 21 Ne and 10 Be production rates in quartz were not significantly greater during the proposed period of decreased magnetic strength from 20 to 50 ka. • Total reference production rates at SLHL are calculated in 72 ka quartz. • Cosmogenic 21 Ne, 10 Be, and 14 C rates ( St ): 17.0 ± 1.1, 3.84 ± 0.27, and 11.2 ± 0.6 at/g/yr. • These rates agree with St scaled production rates over past 20 ka in literature. • There is a proposed period of decreased geomagnetic field strength from 20 to 50 ka. • SPICE rates do not record increased cosmogenic nuclide production over past 72 ka.

Drought-Mediated Changes in Tree Physiological Processes Weaken Tree Defenses to Bark Beetle Attack.

Interactions between water stress and induced defenses and their role in tree mortality due to bark beetles are poorly understood. We performed a factorial experiment on 48 mature ponderosa pines (Pinus ponderosa) in northern Arizona over three years that manipulated a) tree water stress by cutting roots and removing snow; b) bark beetle attacks by using pheromone lures; and c) phloem exposure to biota vectored by bark beetles by inoculating with dead beetles. Tree responses included resin flow from stem wounds, phloem composition of mono- and sesqui-terpenes, xylem water potential, leaf gas exchange, and survival. Phloem contained 21 mono- and sesqui-terpenes, which were dominated by (+)-α-pinene, (-)-limonene, and δ-3-carene. Bark beetle attacks (mostly Dendroctonus brevicomis) and biota carried by beetles induced a general increase in concentration of phloem mono- and sesqui-terpenes, whereas water stress did not. Bark beetle attacks induced an increase in resin flow for unstressed trees but not water-stressed trees. Mortality was highest for beetle-attacked water-stressed trees. Death of beetle-attacked trees was preceded by low resin flow, symptoms of water stress (low xylem water potential, leaf gas exchange), and an ephemeral increase in concentrations of mono- and sesqui-terpenes compared to surviving trees. These results show a) that ponderosa pine can undergo induction of both resin flow and phloem terpenes in response to bark beetle attack, and that the former is more constrained by water stress; b) experimental evidence that water stress predisposes ponderosa pines to mortality from bark beetles.

Fay Weldon, Feminism, and British Culture by Mara E. Reisman (review)

Reviewed by: Fay Weldon, Feminism, and British Culture by Mara E. Reisman Jeffery Moser Mara E. Reisman. Fay Weldon, Feminism, and British Culture. Lanham: Lexington Books, 2018. 171 p. The enigma of the influential and successful author Fay Weldon (1931) is that no reader should be certain whether the Birmingham-born writer's overall aim is to wholly define and refine womanhood or to re-imagine what womanhood is supposed to be. I mean, even one of Weldon's books is titled "What Makes Women Happy" (2006). So what critic, literary or otherwise, would ever dare to discount and dismiss this best-loved writer's successful pursuit of both paths? Assuredly, Weldon has spent the past half-century explaining, defending, excusing, chastising, re-creating, moralizing, illustrating, ruminating, and entertaining about the female condition through more than sixty novels, novellas, short stories, dramas, chapbooks, and [End Page 227] essays. It is true that her fiction is a lot like that by Gloria Naylor, Caryl Churchill, and Julia Alvarez, but Weldon also stands apart from each of these novelists who also write about women, as much as they stand apart from her. Fay Weldon has her own words and wisdom, and she applies them with wit and experience to comment about the present state of the individual, intimacy, and literature. Simply put, if anyone wants to learn about what makes women happy and whether sexual relationships are everything that they are popularly cracked up to be, then read, enjoy, and fall in love with Fay Weldon's writings. For womanhood is most acutely what it is and always has been – acknowledged by one of Weldon's fictional characters – a "symbol of success" and a "symptom" of it (Down Among the Women, 1971). Hence, while Weldon seldom, if ever, disappoints her readers, she almost inevitably provokes and inspires them about the inventions, limits, and possibilities of women and how they--along with, and aside from, men in matters of gender, sexual politics, friendship, family, and modern life and literature—raise concerns about ethics, morality, and personal and corporate responsibility, which all of us should think about, and then think again. For as much as Weldon's writing entertains with satire, humor, and directness about the relationships between men and women, she also explores and analyzes issues of memory, feminism, diversity, and cultural history. Even the topics of food and chocolate are put under the spyglass and given the taste test. As a result, by focusing on a plethora of aspects about femininity and the man-woman thing—what Weldon labels "the truths"—this prolific author has faithfully piqued the public's interest for over fifty years while also interrupting the public's intellect about identity, British nationhood, and the unsentimental reality of our modern world. Therefore, capturing the essence of almost six decades of Weldon' commentary about the female condition and social concerns requires a significant accounting and holistic review of the challenges and controversies that Fay Weldon's books and herself as an author offer. Fortunately, for fans and scholars of Weldon, Mara E. Reisman undertook this challenge. Reisman is associate professor of British literature and women's literature at Northern Arizona University. Her 2018 comprehensive literary analysis and historical overview of Weldon and her work is, as the American academic and humorist Regina Barreca states on the [End Page 228] back cover, an "engaging" study to "be recognized by scholars and critics as a useful, erudite, and lively exposition of sex, class, humor, feminism, and the art of publishing over the last half-century." With the subtitle, "Challenging Cultural and Literary Conventions," Reisman's book reviews and examines Weldon's works through seven chapters that concentrate on the on-going social and critical debates about women, sex, feminism, fiction, and nonfiction. Reisman does not address all of Weldon's writings, but she admits this in her introduction and states that, "I have chosen representative works from each decade that speak to the multiple controversies and challenges to convention in which Weldon and her books played a key role" (xiii). Thus, Reisman has laid out the chapters chronologically, from Weldon's earliest publications to the most recent. She uses the backdrop of...

TWO RECONSTRUCTIONS OF AUGUST–JULY PRECIPITATION FOR CENTRAL NORTHERN ARIZONA FROM TREE RINGS

This study reports two multi-century regional reconstructions of annual precipitation based on Pinus ponderosa and P. edulis from four sites in central northern Arizona. It compares standard regional and time-nested methods to generate reconstructions from 1581–2016 C.E. and 1529–2016 C.E., respectively. The strongest climate relationship is a positive correlation between total ring width and 12-month total precipitation ending in July of the growth year. The chronologies account for 50% of the variance of observed annual precipitation in the regional model and 59%, 60%, and 47% and 35% in the nested models. The two reconstructions are highly correlated (Pearson's correlation r > 0.97, p < 0.001) demonstrating that the reconstructions are highly similar over the period common to both reconstructions, with the nested-models’ advantage of extending the range of the reconstruction. The precipitation reconstructions are significantly correlated (r = 0.66, p < 0.001) with the North American Drought Atlas (NADA).

Tree and opening spatial patterns vary by tree density in two old-growth remnant ponderosa pine forests in Northern Arizona, USA

Forest spatial patterns influence many ecological processes in dry conifer forests. Thus, understanding and replicating spatial patterns is critically important in order to make these forests sustainable and more resilient to fire and other disturbances. The labor and time required to stem-map trees and the large plot size (>0.5 ha) needed to study tree spatial patterns have limited our examination of how these patterns change as a function of site conditions and tree densities. We stem-mapped all trees >40 cm DBH within two large relict (minimally logged) pure ponderosa pine study sites on experimental forests at Long Valley (73 ha) on sedimentary soils and Fort Valley (32 ha) on basalt soils in northern Arizona, USA. We also simulated 1,000 4-ha plots from models of each study site incorporating field data parameters. Using cluster analysis and field data, we found that an inter-tree distance (ITD) of 9–11 m best separated single trees and groups within our study sites. Using a fixed 10-m ITD, the more productive Long Valley (LV) site had 62 trees ha−1 and groups of up to 113 trees, compared to the Fort Valley (FV) site, which averaged 41 trees ha−1 and had 22 trees in the largest group. However, the sites differed only slightly in terms of single trees ha−1 (LV 7.3; FV 5.6) and group of tree ha−1 (LV 7.2; FV 8.1). Simulation results indicated that when tree densities are equal, the spatial patterns were very similar between the two sites, suggesting that tree spatial pattern variability is a function of tree densities and only indirectly related to site productivity. As the number of trees increased, the additional trees integrated into existing groups rather than creating new groups. In addition to tree spatial patterns, we quantified gaps (defined as >30 m wide stem-to-stem) and openings (defined as ≥30 m wide stem-to-stem) within the two study sites. Although both sites were dominated by small openings most of the open area was found within a few large openings. Our large plots allowed us to incorporate variability and capture a larger range of tree and openings spatial patterns than have been captured in previous studies to provide insights on spatial heterogeneity that can inform management of this important forest type in North America.

The importance of municipal and agricultural demands in future water shortages in the United States

We examine how future changes in water yield and demand will affect the likelihood of water shortages and the efficacy of some of the most common methods for dealing with water shortages and meeting municipal demands, including improvements in water use efficiency and transfers of water between sectors of the economy. We find that more than 45.8 million people, primarily in the Southwest, central Great Plains, and southern California, would already be experiencing regular water shortages in the absence of groundwater mining. By 2060, that number would grow to over 136.2 million people. Among the reasons we find for increased likelihood of water shortages, reduced water yield is the most prevalent, affecting 80% of water basins in the US In the American West, nearly half of the water basins are projected to see an increase in shortages. We estimate future water withdrawals in the industrial and commercial and thermoelectric sectors will remain fairly steady, but withdrawals in the domestic and public sector are expected to rise. The Colorado River and Rio Grande regions see the largest percentage increases in projected domestic and public water use as well as the greatest percentage decreases in projected water yield. To cover new municipal demands, transfers from agriculture may be needed, in which case, significant impacts to agriculture will occur in northern New Mexico, parts of Utah, Nevada, and Washington where municipal demands are projected to grow to 25%–50% of agricultural water use. The situation is more extreme in northern Arizona and eastern Texas, where additional municipal demands are projected to be six times the amount used by agriculture.

Review: Improvisation and Social Aesthetics, edited by Georgina Born, Eric Lewis, and Will Straw

Book Review| August 01 2019 Review: Improvisation and Social Aesthetics, edited by Georgina Born, Eric Lewis, and Will Straw Improvisation and Social Aesthetics, edited by Georgina Born, Eric Lewis, and Will Straw. Improvisation, Community, and Social Practice. Durham, NC: Duke University Press, 2017. vii, 345 pp. Rob Wallace Rob Wallace ROB WALLACE is a Lecturer in the Honors College at Northern Arizona University. In addition to numerous articles, reviews, recordings, and poetry, he is the author of Improvisation and the Making of American Literary Modernism (Continuum, 2010) and coeditor of People Get Ready: The Future of Jazz Is Now! (Duke University Press, 2013). Search for other works by this author on: This Site PubMed Google Scholar Journal of the American Musicological Society (2019) 72 (2): 595–599. https://doi.org/10.1525/jams.2019.72.2.595 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Rob Wallace; Review: Improvisation and Social Aesthetics, edited by Georgina Born, Eric Lewis, and Will Straw. Journal of the American Musicological Society 1 August 2019; 72 (2): 595–599. doi: https://doi.org/10.1525/jams.2019.72.2.595 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentJournal of the American Musicological Society Search Improvisation and Social Aesthetics, the latest volume in the series Improvisation, Community, and Social Practice published by Duke University Press, is a welcome addition to the ever-expanding field of critical improvisation studies. Indeed, many of the book's contributors are innovators in the field, and many are also directly involved with the international research project that inspired the book series, now called the International Institute for Critical Studies in Improvisation, or IICSI. (The present reviewer is a Research Associate of this institute.) The book itself originated in a conference held at McGill University in 2010, one of the many symposia that generated IICSI. This brief context is important, since many musicologists may not be directly familiar with IICSI, and because a wide swath of the research coming from IICSI is beyond the range of conventional musicological discourse. Nevertheless, as the presence of figures such as Georgina Born, Lisa Barg, and... You do not currently have access to this content.

A Putative Hybrid between Phoradendron juniperinum and P. capitellatum (Viscaceae) from Northern Arizona

Juniper mistletoe (Phoradendron juniperinum, Viscaceae) and hairy mistletoe (P. capitellatum) commonly parasitize junipers (Juniperus spp.) in Arizona. Although hybridization between species of Phoradendron is rare, this note reports the occurrence of a putative hybrid between these mistletoes in northern Arizona. The principal characteristics of the hybrid plant are the length, width, and pubescence of leaves, which are intermediate between the parent species. The putative hybrid is a female plant, and although it flowered and formed 17 fruits in 2017, seeds from the mature fruits did not germinate, suggesting that the hybrid is probably sterile.

Stand Dynamics of Pinyon-Juniper Woodlands After Hazardous Fuels Reduction Treatments in Arizona

Pinyon-juniper ecosystems occur extensively across western North America, and at the landscape scale, variation in structure and composition is influenced by topographic position, soils, disturbance history, and local climate. The persistent pinyon-juniper woodland is a common structural form, and though they are known to be infrequent-fire systems, there is increasing interest in implementation of hazardous fuels reduction treatments in woodlands, especially in the wildland-urban interface. Few studies have quantified stand dynamics following fuels reduction treatments in persistent woodlands or compared treatment outcomes to conditions that develop under natural disturbance and successional processes. In 2004, we established a randomized, replicated study in woodlands of northern Arizona, and monitored stand dynamics and understory responses to determine how stand-level changes differed between common fuels reduction approaches. We compared the resulting structure with a conceptual state-and-transition model. Results showed that, over the 11 yr after treatment, juniper tree densities decreased by 8.4% and 0.9% but increased by 14.0% and 27.3% in Control, Burn, Thin, and Thin + Burn treatments, respectively. Pinyon tree densities decreased by 1.1% and 3.3%, increased by 12.2%, and decreased 7.9% in Control, Burn, Thin, and Thin + Burn treatments, respectively. All treatments showed fuel load reductions throughout the 11-yr study period and minimal rebound of tree recruitment toward pretreatment conditions. Prescribed fire alone (Burn) maintained persistent woodland conditions. Thinning treatments substantially reduced small tree densities and, with the addition of prescribed fire, produced losses of large trees. Thinning with prescribed fire (Thin + Burn) tended to produce conditions qualitatively unlike those described by our state-and-transition model. Evaluation of these commonly used fuels treatments against our state-and-transition model suggested that concerns regarding loss of ecological integrity may be warranted.

A Methodology For Disaggregation and Textural Analysis of Quartz-cemented Sandstones

AbstractSandstone textures provide critical information for reservoir modeling and interpreting depositional processes. While loose sand textures are easy to describe, various authors have developed thin-section and image-analysis techniques to characterize lithified deposits that were assumed impossible to disaggregate successfully. These methods are effective but tedious, and are generally not feasible for processing many samples. We present a new methodology for disaggregating quartz-dominated sandstones cemented by quartz overgrowths, with application to the Permian Coconino Sandstone of northern and central Arizona, USA. Textural parameters of the disaggregated sand were measured using a laser diffraction particle analyzer. Our average grain sizes from laser analysis are coarser than those from thin section (as expected), but trends from the analyzer correlate well with thin-section results. This strong correlation strengthens the validity of both methods and suggests that disaggregation and whole-particle analysis may effectively replace petrographic techniques in many textural studies. We hope that our methods, which increase the efficiency of grain-size analysis, will expand the potential for collecting textural data from quartz-cemented sandstones.

The transition from bee-to-fly dominated communities with increasing elevation and greater forest canopy cover.

Insect pollinator communities are thought to transition from bee-dominated communities at low elevations to fly-dominated communities at high elevations. We predicted that increased tree canopy cover and a subsequent decrease in meadows and flowering plants would limit bees but not flies at higher elevations. We tested and supported this prediction by examining changes in both abundance and species richness for 128 bee species and 96 fly species at key points along an elevational gradient in Northern Arizona represented by distinct vegetation life zones. In addition to an increase in fly species and abundance relative to bees with increasing elevation, there were changes in community structure). To better understand factors that might influence this transition we examined how tree canopy cover changed along the elevational gradient and how this influenced the change in insect pollinator communities. While bee communities were progressively divergent between forest and meadow habitats with increasing elevation and tree canopy cover, there was no significant pattern with flies between meadow and forest habitats. However, fly abundance did increase with increasing elevation relative to bees. Along a comparable elevational gradient on an adjacent mountain with no tree canopy cover (i.e., a fire burned mountain), the bee-to-fly transition did not occur; bees persisted as the dominant pollinator into the highest life zone. This suggests that tree canopy cover can in part explain the transition from bee-to fly-dominated communities. In conclusion, this is the first study in North America to document a bee-fly transition for both abundance and species richness and show that tree canopy cover may play a role in determining pollinator community composition, by restricting bees to open meadow habitats.