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Hydroperiod, or the amount of time a lentic waterbody contains water, shapes communities of aquatic organisms. Precise measurement of hydroperiod features such as inundation timing and duration can help predict community dynamics and ecosystem stability. In areas defined by high spatial and temporal variability, fine‐scale temporal variation in inundation timing and duration may drive community structure, but that variation may not be captured using common approaches including remote sensing technology. Here, we provide methods to accurately capture inundation timing by fitting hidden Markov models to measurements of daily temperature SD collected from temperature loggers. We describe a rugged housing design to protect loggers from physical damage and apply our methods to a group of intermittent ponds in southeastern Arizona, showing that initial pond inundation timing is highly variable across a small geographic scale (∼50 km2). We also compare a 1‐logger (pond only) and 2‐logger (pond + control) design and show that, although a single logger may be sufficient to capture inundation timing in most cases, a 2‐logger design can increase confidence in results. These methods are cost‐effective and show promise in capturing variation in intraregional inundation timing for a range of temporary lentic habitats that may have profound effects on aquatic communities, with implications for how these communities may respond to hydroperiod alteration from a changing climate. Key Points: Hydroperiod inundation timing and duration are key factors that drive many biotic processes in temporary lentic watersTools to assess fine‐scale hydroperiod dynamics are needed to understand and predict responses of lentic habitats to a changing climateUse of temperature loggers and hidden Markov models are a cost‐effective and reliable way to estimate hydroperiod dynamics [ABSTRACT FROM AUTHOR]

To better understand risk management and mutual aid among American ranchers, we interviewed and mailed a survey to ranchers in Hidalgo County, New Mexico, and Cochise County, Arizona, focusing on two questions: (1) When do ranchers expect repayment for the help they provide others? (2) What determines ranchers' degrees of involvement in networks of mutual aid, which they refer to as "neighboring"? When needs arise due to unpredictable events, such as injuries, most ranchers reported not expecting to be paid back for the help they provide. When help is provided for something that follows a known schedule or that can be scheduled, such as branding, most ranchers did expect something in return for the help they provide. This pattern makes sense in light of computational modeling that shows that transfers to those in need without expectations of repayment pool risk more effectively than transfers that create debt. Ranchers reported helping other ranchers more often when they belonged to more religious and civic organizations, when they owned larger ranches, when they relied less on ranch vs. other income, and when they had more relatives in the area. Operators of midsize ranches reported helping other ranchers more frequently than did those on smaller and larger ranches. None of our independent variables predicted how many times ranchers reported receiving help from other ranchers. Although ranch culture in the American West is often characterized by an ethic of individualism and independence, our study suggests that this ethic stands alongside an ethic of mutual aid during times of need. [ABSTRACT FROM AUTHOR]

The Transitional Zone of central Arizona is a mountainous region dissected by rivers that created barriers and drove movement between prehistoric Hohokam groups to the south and Ancestral Peoples groups to the northeast and northwest. Although never suitable for large-scale agricultural irrigation, this region provided small areas of arable land scattered across rugged terrain rich in wild foods and alboreal resources. Archaeological data recovery related to road improvement projects throughout Arizona Route 260 allowed us to examine paleobotanical and osteofaunal remains of five archaeological sites. We relate changes in diet breadth and anthropogenic land effects modeled and described using the methods of the optimal foraging theory, with modes of use modeled using concepts from the frontier theory. We found that brief intervals of prey suppression and concomitant expansion of diet breadth between low value resources coincide with intervals of prey recovery and diet amplitude contraction between low value resources and more intensive settlement. On the other hand, ranges of prey recovery and diet breadth contraction among low value resources coincide with a reduced population and seasonal, extractive, and short-term occupations. [ABSTRACT FROM AUTHOR]

Turquoise has been used in the American Southwest since “time immemorial,” and remains an important material for contemporary indigenous groups of the region. Detailed studies of ancient turquoise mines are few, however, and inferences of turquoise procurement and provenance have been limited. Our intensive investigation of one mine, the Canyon Creek locale in Arizona, integrates archaeology and geochemistry to enhance understanding of the mine and its output. A detailed description of the mine's morphology and geologic setting lays foundations for interpreting an isotopic analysis of specimens from the mine's four localities. The analysis reveals extremely radiogenic Pb isotope ratios, which distinguish Canyon Creek turquoise from that of other known sources in the American Southwest. Its distinctive isotopic signature makes Canyon Creek turquoise readily identifiable in archaeological assemblages. The presence of turquoise from Canyon Creek at late prehispanic settlements in east-central Arizona helps clarify the mine's chronology of use and regional distribution. Our observations suggest the mine was larger than previously supposed, and that it provided an important source of turquoise for inhabitants of the region during the thirteenth and fourteenth centuries AD. [ABSTRACT FROM AUTHOR]

The protistan genus Epistylis contains freshwater colonial species that attach to aquatic organisms in an epibiotic or parasitic relationship. They are known to attach to the epidermis and shells of aquatic turtles, but have not been reported to cause heavy infestations or morbidity in turtles. We documented heavy infestations of Epistylis spp. in several populations of Sonoran mud turtles (Kinosternon sonoriense) inhabiting livestock ponds in Arizona, USA, and rough-footed mud turtles (Kinosternon hirtipes) from livestock ponds in Texas, USA, over the course of several years. Severe Epistylis spp. infestations on mud turtles appeared to alter diving and swimming behavior when compared to uninfested conspecifics. Infestations were cleared in captivity using tap water or a 10% salt solution, and the turtles had no permanent damage to their shell or epidermis upon clearing. While several of the mud turtles we observed had poor body condition, it is possible that the severe infestations we observed were caused by a comorbidity associated with a pathogen, parasite, or poor habitat quality that made the turtles more susceptible to the Epistylis spp. infestation. Further research on causes for these severe infestations are warranted because they contribute to changes in behavior of the heavily infested turtles and may contribute to morbidity in Kinosternon spp. when mud turtles inhabit extremely warm, shallow, eutrophic aquatic habitats, such as livestock ponds., (© Wildlife Disease Association 2023.)

Abstract: Eight prehistoric wells dug to a depth of ∼2 m below the modern ground surface were found in the alluvial sediments of McClellan Wash on Gila River Indian Community in southern Arizona. Charcoal from the sediments filling the wells yielded radiocarbon ages of ∼1000 B.C. The time in which wells were dug coincides with a period of general regional aridity and high ENSO activity in the American Southwest. Digging to access water may have occurred in response to period(s) of resource uncertainty, or as a logistical activity that engaged increasingly resource-tethered Late Archaic/Early Agricultural populations. These activities laid the foundation for agricultural practices that eventually became the dominant mode of subsistence in the low-lying areas of the Sonoran Desert. [Copyright &y& Elsevier]

The American southwest has among the best solar resources in the world. For this reason, the solar industry monitors the progress of solar energy development there closely. Yet, meaningful adoption has been slow, particularly in the state with the richest resource, Arizona. This article reports on the results of internet surveys and personal interviews to explain why this is true. We focused on identifying industry-perceived barriers to solar adoption. We asked three questions: (1) Which industry factors slow the speed of adoption of solar energy in Arizona? (2) Are there unmet workforce needs that slow adoption in Arizona? (3) Which policy incentives are needed to accelerate solar development? We identified a need for the following steps: establish financial security for projects with newly created and targeted statutory instruments, develop standardized college-level solar curriculum to train a local workforce, and provide conspicuous government support and supportive policy commitments that are sustainable. A systematic and integrated effort with government, industry, educational, and public representation is needed to make solar energy a significant contributor to the future economic vitality of the state, thereby helping to advance such adoption in other places with similar opportunities for solar energy development. [ABSTRACT FROM AUTHOR]

This study presents a revision of Dean E. Arnold's (1985, 1993) Exploitable Threshold Model, which attempts to explain the selection of raw materials for pottery production. Arnold's model posits that potters' preferences for materials are largely determined by the linear distance to individual resources. We argue, however, that potters' choices are, at least in part, determined by spatial relationships among the necessary resources rather than the distances to them. This study of 14th century pottery production on Perry Mesa, Arizona demonstrates that potters selected materials based on the co-occurrence of readily available sources of temper, clay, and fuel. Lack of water and fuel sources on the mesa top compelled local residents to eschew the use of readily available basaltic sands to temper their plainware pottery. Instead, Perry Mesa potters selected granitic sands from the river valley nearly 300 vertical meters below their settlements. [ABSTRACT FROM AUTHOR]

In the field of archaeological palynology, charcoal and ash debris in sediments have been among the palynologists' worst enemies. Too often important pollen information is found in the soils of sites near fire hearths where the members of ancient cultures would gather to eat and conduct social activities, and in winter sleep. near the fire. For decades archaeological palynologists have searched for ways to remove the thousands of tiny flecks of charcoal and ash in these samples so the fossil pollen can be observed. Until now, no technique has proven adequate for successful charcoal removal without the loss of pollen. We have not completely solved this problem, but we have developed an extraction method that significantly reduces the amount of included charcoal and ash in archaeological sediments. We tested this new extraction procedure on charcoal-laden archaeological sediments from a pueblo site in Arizona. The result demonstrates the advantage of using this new pollen extraction procedure for certain types of archaeological soils. [ABSTRACT FROM AUTHOR]

The article examines the Colorado River's natural and cultural systems and the outlook for the river's viability as a renewable water source that will support human habitation in the region of the Colorado River Basin. The discussion focuses on the influence of humans on the natural world in the American Southwest, water use, sustainability, and environmental values. The disappearance of the Santa Cruz River, water consumption in cities such as Tucson in Arizona, water extraction from aquifers under the Sonoran Desert, and the occurrence of subsidence after the removal of groundwater are mentioned.

Abstract: As part of a study to investigate the causes of channel narrowing and incision in Canyon de Chelly National Monument, the effects of Tamarisk and Russian-olive on streambank stability were investigated. In this study, root tensile strengths and distributions in streambanks were measured and used in combination with a root-reinforcement model, RipRoot, to estimate the additional cohesion provided to layers of each streambank. The additional cohesion provided by the roots in each 0.1-m layer ranged from 0 to 6.9 kPa for Tamarisk and from 0 to 14.2 kPa for Russian-olive. Average root-reinforcement values over the entire bank profile were 2.5 and 3.2 kPa for Tamarisk and Russian-olive, respectively. The implications of vegetation removal on bank stability and failure frequency were evaluated in two incised reaches by modeling bank-toe erosion and bank stability with and without vegetation. The effects of a series of 1.0- and 1.5-m-deep flows on bank-toe erosion, pore-pressure distributions, and bank stability were evaluated first. In addition, bank stability model runs were conducted using iterative modeling of toe erosion and bank stability using a discretized flow and groundwater record for one year. Results showed that the effects of root-reinforcement provided by Tamarisk and Russian-olive have a significant impact on bank-stability and bank-failure frequency. Because the bank materials are dominated by sands, cohesion provided by roots is significant to bank stability, providing an average 2.8 kPa of cohesion to otherwise cohesionless bank materials. Bank retreat rates at one site following vegetation removal have approximately doubled when compared to the control reach (from an approximate rate of 0.7–0.8 m/y between 2003 and 2006 to 1.85 m/y during the year modeled). Vegetation removal along the entire riparian corridor in Canyon de Chelly may lead to the introduction of significantly more sediment to the system through bank widening processes, although it is not known whether this change alone would be sufficient to cause a shift in channel morphology to the wide-braided channels that were once characteristic of this canyon. [Copyright &y& Elsevier]

The Western Pueblos in the American Southwest have been subject to over 450 years of historic contact, yet a myth has emerged about their unchanging nature. A detailed examination of historical documents and photographs reveals, instead, where postcontact technological and social influences have occurred, especially with regard to pueblo households, use of space, increases in room sizes, dwelling construction, kivas, and agricultural processing and storage facilities. A dynamic ethnographic model is proposed that takes into account both postcontact changes and continuity in Western Pueblo society and how these processes can be used for understanding the archaeological record. [ABSTRACT FROM AUTHOR]