Northwestern Oklahoma Research Articles

Assessment of Oklahoma Phlox (Phlox oklahomensis: Polemoniaceae) in the Gypsum Hills of Northwestern Oklahoma and Southern Kansas

Phlox oklahomensis Wherry, Oklahoma phlox, occurs within the tall grass prairie of the southern Flint Hills of Kansas, and other populations occur within the southern mixed grass prairie of the Gypsum Hills of northwestern Oklahoma and southern Kansas. The first census of Oklahoma phlox in northwestern Oklahoma and southern Kansas was conducted over a three-year period (1980-1982). The second and third censuses occurred approximately 20 years after the first census, in 2002 and 2003. Since the 1980s two major wildfires and several droughts have occurred throughout its distribution range. The goals of this research were to compare the 1980-1982 census and the 2002 and 2003 censuses of Oklahoma phlox to censuses conducted in 2020 and 2021 and assess the current status of the species. In addition, we used a geographic information system (GIS) to identify factors that influence the likelihood of finding Oklahoma phlox in the region. The final census found that the occurrence of Oklahoma phlox has not changed significantly over the last 40 years. Populations thrive in areas where the fire interval is >5 years, and it commonly occurs on the upper elevations of the landscape on hilltops and/or ridges where the slope is > 7%. Although plants were observed on all landscape exposures, populations occur more frequently on west and northwest facing slopes. The authors recommend an S3 ranking for Oklahoma phlox.

Right-Moving Supercell Tornadogenesis during Interaction with a Left-Moving Supercell’s Rear-Flank Outflow

Abstract On the local afternoon of 29 May 2012, a long-lived, right-moving (RM) supercell formed over northwestern Oklahoma and turned roughly southeastward. For >3 h, as it moved toward the Oklahoma City, Oklahoma, metro area, this supercell remained nontornadic and visually high-based, producing a nearly tornadic gustnado and a swath of significantly severe, sometimes giant hail up to 5 in. (12.7 cm) in diameter. Meanwhile, a left-moving (LM) supercell formed over southwestern Oklahoma about 100 mi (161 km) south-southwest of the RM storm, and moved northeastward, with a rear-flank gust front that became well defined on radar imagery as the LM storm approached southern and central parts of the metro. The authors, who had been observing the RM supercell in the field since genesis, surmised its potential future interaction with the LM storm’s trailing gust front about 1 h beforehand. We repositioned to near the gust front’s extrapolated collision point with the RM mesocyclone, in anticipation of maximized tornado potential, then witnessed a small tornado from the RM mesocyclone immediately following its interception of the boundary. Synchronized radar and photographic images of this remarkable sequence are presented and discussed in context of more recent findings on tornadic supercell–boundary interactions, with implications for operational utility. Significance Statement Supercells—well-organized, rotating thunderstorms mainly found in midlatitudes—commonly produce the largest hail, along with damaging gusts and most tornadoes. In radar imagery and photographs, we show the characteristics and merger of two supercell types: left-moving and right-moving, with respect to winds aloft. As the left-moving storm’s trailing gust front interacted with the right-mover’s mesocyclone, the latter strengthened quickly, soon producing a tornado. Observed evolution of these storms supports idealized numerical and conceptual models for supercell behavior and interactions with storm-scale boundaries, and may be useful in short-fused tornado forecast and warning operations.

Detection of Babesia conradae in Coyotes (Canis latrans) and Coyote-Hunting Greyhound Dogs (Canis familiaris).

Babesia conradae is a small piroplasm previously detected in coyote-hunting Greyhound dogs in California and Oklahoma. In dogs, B. conradae causes clinical signs similar to other tick-borne illnesses, and if not treated it can lead to acute kidney injury and other life-threating complications. To date, the life cycle of this apicomplexan parasite has not been fully described, but suggestions of direct contact or tick transmission have been proposed. The purpose of this study was to test coyote tissue samples from coyotes hunted by Greyhound dogs with a history of B. conradae infection to determine if this parasite is present in the coyote population in Northwestern Oklahoma. The analyzed tissue samples included liver, lung and tongue samples collected by hunters. DNA was isolated from these tissues and assessed by RT-PCR of the 18S rRNA and PCR of the COX1 genes for B. conradae. A total of 66 dogs and 38 coyotes were tested, and the results demonstrated the presence of B. conradae DNA in 21 dogs (31.8%) and 4 coyotes (10.5%). These results indicate that B. conradae is present in the dog and coyote population from the same area and that direct contact with coyotes may increase the risk of infection in dogs. Further studies are required to test possible modes of transmission, including direct bite, tick or vertical transmission.

359 Using an Extruded 100% Dried Distillers' Grains Cube to Intensify Production in a Stocker Grazing Enterprise on Native Range in Northwestern Oklahoma

Abstract A 2-year experiment was conducted at the USDA-ARS Southern Plains Experimental Range (SPER) near Fort Supply, OK to define the effects of supplementing steers grazing native range with extruded 100% dried distillers' grains (DDGS) cubes. Each year 126 steers (259 ± 43 kg) grazed from late May to late September allocated to 3 treatments: 1) negative control (NC) stocked at 2.4 ha/steer with ad libitum mineral only, 2) positive control (PC), supplemented with 1.8 kg/steer on alternate days during the late summer stocked at 2.4 ha/steer, and 3) high supplement (HS) fed 0.75% BW supplemental DDGS cubes all season stocked at 1.6 ha/steer. Data were analyzed across years using PROC MIXED in SAS as a complete block design using year as the random block and pasture within treatment by year as the error term. Early season ADG and BW gains for HS were 0.30 ± 0.031 kg and 20 ± 2.1 kg greater (P < 0.01) than NC and PC, respectively. However, late season ADG for HS and PC steers were 0.34 ± 0.08 and 0.36 ± 0.08 kg greater (P < 0.01) than NC. Late season BW gains for HS and PC did not differ (P ≥ 0.76) but were 22.3 ± 5.3 and 23.9 ± 5.4 kg greater than NC, respectively. Hence, overall ADG, total BW gain, and BW gain/ha for HS were 0.32 ± 0.04, 0.14 ± 0.04; 42 ± 5.4, 18 ± 5.4; and 53 ± 2.2, 42 ± 2.2 kg greater (P < 0.01) than NC and PC, respectively. Supplementing 100% DDGS cubes during summer grazing is an effective management option to increase stocking rates without negatively impacting individual animal performance, and increasing gain/hectare.

179 Using a 100% Dried Distillers Grains Cube as a Supplement for Steers Grazing Mixed Grass Prairie in Oklahoma

Abstract This research was conducted to determine effects of supplementation and implanting on BW gain by steers grazing mixed grass prairie (n = 12 pastures, 19.9 ± 0.7 ha) in northwest Oklahoma. Three main plot treatments were: 1) Negative Control (NC), no supplementation, 2) Positive Control (PC), supplemented with DDGS cubes, 1.8 kg/steer on alternate days in late summer, 3) High Supplement (HS), 1/3 increase in stocking rate with 0.75% BW supplemental DDGS cubes all season. Steers (n = 125, BW = 223.1 ± 23.2 kg) were stocked at 2.2 ha/steer for PC and NC, 1.3 ha/steer for HS. Grazing was from May 17 – September 27 (132 d). All steers were implanted with 200 mg progesterone and 20 mg estradiol benzoate (SYN, Synonvex S, Zoetis Animal Health) on May 17. On July 18 three reimplant treatments were applied: 1) no reimplant; 2) SYN; or 3) 40 mg trenbolone acetate and 8 mg estradiol (Revalor G, Merck Animal Health). Data were analyzed using the PROC MIXED in SAS as a split-plot experimental design. In early summer HS had 0.26 kg greater (P < 0.01) ADG than NC and PC. Late summer gains of PC were 0.33 kg/d more (P ≤ 0.01) than NC; and HS gained 0.49 and 0.16 kg/day more (P ≤ 0.04) than NC and PC, respectively. Gain per hectare for PC (46 kg/ha) were greater (P < 0.01) than NC (35 kg/ha) and more than doubled (P < 0.01) with HS (89 kg/ha). Reimplanting had no effect on ADG (P ≥ 0.28). Late season supplementation with PC resulted in supplemental efficiency of 2.7 kg supplement/kg added gain compared with NC. Increased stocking rates with season long supplementation in HS resulted in supplemental efficiency of 3.8 kg supplement/kg added gain per hectare. Based on these data, a 100% DDGS cube is an effective supplement option to increase BW gain during the late summer or increase carrying capacity and gain during the summer grazing period in northwestern Oklahoma.

Spatial and temporal patterns of drought in Oklahoma (1901–2014)

This study uses the Standardized Precipitation Evapotranspiration Index (SPEI) at a 6‐month timescale to document the spatial and temporal patterns of drought in Oklahoma from 1901 to 2014. A principal component analysis (PCA) with a VARIMAX rotation was used to divide Oklahoma into four spatially contiguous regions with similar drought patterns that are located in northwestern, northeastern, southwestern and southeastern regions of the state. Droughts tend to occur more frequently in northwestern Oklahoma, but all four regions show that droughts in Oklahoma have substantial variability at decadal timescales. A Mann–Kendall trend test demonstrates that there has been a statistically significant increase in the SPEI in Oklahoma since 1901. This indicates that conditions are generally getting wetter in Oklahoma. However, there is substantial variability in moisture conditions that is evident at shorter timescales. Prolonged periods of drier than normal conditions occurred in the 1910s, 1930s, 1950s, 1970s and 1980s, while conditions from the 1980s to the 2000s have been wetter than normal. Recently, the SPEI has decreased, which suggests that Oklahoma may be at the beginning of another dry cycle. In addition, while most droughts during the study period were caused by decreases in precipitation, recent droughts, such as the severe drought in 2011, were caused by both decreases in precipitation and increases in potential evapotranspiration. This may be indicative of future drought conditions in Oklahoma.

Use of whole genome sequencing to complement characterisation of a typhoid fever outbreak among a Marshallese community: Oklahoma, 2015.

Typhoid fever is an illness caused by Salmonella enterica serotype Typhi. In developing regions, it affects an estimated 20 million people annually, causing 200 000 deaths. Although uncommon, cases occur in the USA each year, predominantly due to international travel. During February 2015, the Oklahoma State Department of Health (OSDH) detected an outbreak of typhoid fever among residents of northwestern Oklahoma. OSDH conducted case-patient interviews to identify the source and symptomatic contacts. Whole genome sequencing (WGS) was performed to characterise the genetic relatedness of isolates among the four outbreak-associated pulsed-field gel electrophoresis (PFGE) patterns. We identified 38 cases, 25 confirmed and 13 probable, in two states. WGS revealed a 0-10 single-nucleotide polymorphism variation between isolates. Although we were unable to determine the source, almost all case-patients were members of the Marshallese community that attended a common event in Oklahoma, or were contacts to a confirmed case. This is the largest outbreak of typhoid fever in the USA since 1989, and first to apply WGS to complement interpretation of PFGE results during a typhoid fever outbreak investigation. This investigation illustrates the potential risk of outbreaks among communities comprised of international populations from regions where typhoid fever remains endemic.

Teaching the Literatures of the American Civil War ed. by Colleen Glenney Boggs

Reviewed by: Teaching the Literatures of the American Civil War ed. by Colleen Glenney Boggs Richmond B. Adams Teaching the Literatures of the American Civil War. Edited by Colleen Glenney Boggs. ( New York: Modern Language Association of America, 2016. Pp. xii, 317. Paper, $29.00, ISBN 978-1-60329-276-4; cloth, $45.00, ISBN 978-1-60329-275-7.) Exploring the literature of the American Civil War remains as daunting as it is overwhelming. To prepare a volume that expands on various ways to teach students about the relationship between the war and the fictions that grew from it becomes more intimidating still. Faced with this task, Colleen Glenney Boggs has compiled a useful and insightful volume of essays in an effort to mitigate what she describes as the period's absence "from our scholarly and pedagogical approaches to American literary studies" (p. 1). Boggs helpfully divides the essays into four sections that address unique approaches to teaching aspects of the war, including works that discuss literature in the historical context of antebellum period and in the war's aftermath, approaches to various literary genres, and a last segment entitled "Teaching Materials." Larry J. Reynolds's essay covers how the antebellum works of Nathaniel Hawthorne and Ralph Waldo Emerson helped shape understandings of the origins of the war. Alison E. Carey's essay examines the seemingly noncanonical but culturally significant dime novels that common soldiers carried into camp and combat. Wiebke Omnus Klumpenhower, drawing on her experience teaching students in South Korea, helpfully provides a way for American readers to grapple with issues they may face while teaching international students. The essay by Darren T. Williamson, Shawn Jones, and William Steele reflects their interdisciplinary team-teaching approach, which involves taking students to actual battlefields as part of a course. It contains superb ideas for broadening student engagement with the war's complexities while potentially saving them the costs of covering the same breadth of material. Catherine E. Saunders's essay examines the poetry of African American soldiers and helps shape the necessary Part 3, "Teaching Specific Topics." Contributions from Jessica DeSpain, Elizabeth Duquette, Matthew R. Davis, Michael Ziser, and Ian Finseth provide an almost literal center to the collection with their corporate and singular examinations of previously unheard voices. Saunders's essay in particular is well balanced by Faith Barrett's earlier examination of not simply "Reading the Civil War in Poetry," as Barrett puts it in [End Page 466] her essay's subtitle, but to do so in conjunction with song. Finseth's contention that the "Civil War did not so much produce literary realism as provide a set of conditions in which a variety of writers (and visual artists) grappled with the meanings of large-scale bloodletting" provides solid grounding for extended discussions of a once-held maxim in American literary history (p. 124). Boggs's collection has easily earned a place within pedagogical and scholarly realms. On a small note, if for no other reason than the ever-increasing number of volumes aimed at assisting teaching efforts, adding an essay or two on strictly literary concerns and perhaps including one fewer on how teaching a topic remains beyond even the best pedagogy might have enhanced the collection. Past that minor matter, Boggs has produced a superb collection that should become part of any university or personal library. Its relatively modest price makes such an acquisition possible. Richmond B. Adams Northwestern Oklahoma State University Copyright © 2018 The Southern Historical Association

The World the Civil War MadeGregory P.Downs and KateMasur, Editors. University of North Carolina Press, 2015.

The Journal of American CultureVolume 40, Issue 4 p. 437-437 Book Review The World the Civil War Made , Gregory P. Downs and Kate Masur, Editors. , 2015. Richmond B. Adams, Richmond B. Adams Northwestern Oklahoma State UniversitySearch for more papers by this author Richmond B. Adams, Richmond B. Adams Northwestern Oklahoma State UniversitySearch for more papers by this author First published: 07 December 2017 https://doi.org/10.1111/jacc.12831Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume40, Issue4December 2017Pages 437-437 RelatedInformation

On the Forcing of the Summertime Great Plains Low-Level Jet

AbstractThe low-level jet (LLJ) is a ubiquitous feature of the lower atmosphere over the Great Plains during summer. The LLJ is a nocturnal phenomenon, developing during the 6–9-h period after sunset. Forcing of the LLJ has been debated for over 60 years, the focus being on two processes: decoupling of the residual layer from the surface owing to nighttime cooling and diurnal heating and cooling of the sloping Great Plains topography.To examine characteristics and forcing mechanisms for the LLJ, composite grids were compiled from the North American Mesoscale Forecast System for the summertime months of June and July over a 5-yr period (2008–12). One composite set was assembled from well-developed LLJ episodes during which the maximum nocturnal jet magnitude at 0900 UTC over northwestern Oklahoma exceeded 20 m s−1. A second set consists of nonjet conditions for which the maximum nighttime wind magnitude in the lowest 3 km did not exceed 10 m s−1.The intensity of the horizontal pressure gradient and hence background geostrophic flow at jet level was the dominant difference between composite cases. The horizontal pressure gradient forms in response to the thermal wind above jet level that results primarily from seasonal heating of the sloping Great Plains. Thermal wind forcing is thus the key link between the Great Plains and the high frequency of LLJ occurrence. The nocturnal wind maximum develops primarily because of the inertial oscillation of the ageostrophic wind occurring after decoupling of the lower atmosphere from the surface owing to radiational cooling in the early evening.

The Pheidole (Hymenoptera: Formicidae) of Oklahoma: new species records and distributional notes

Big-headed ants from the genus Pheidole (Hy­men­optera: Formicidae) are diverse and ecologically important world-wide. Here we report the first record in Oklahoma for two species, Pheidole pelor and Pheidole tysoni, increasing the number of known Pheidole species in Oklahoma to twelve. We highlight two areas, northwestern and southeastern Oklahoma, that may contain undocumented species based on their unique habitat, and stress the importance of surveying the regional fauna of these areas to create a proper baseline for monitoring the effects of environmental change.

Optimizing Eastern Gamagrass Forage Harvests Using Growing Degree Days

Tripsacum dactyloides (L.) L., commonly known as eastern gamagrass, is useful for grazing, stored forage, soil amelioration and conservation, and as a biofuel feedstock. Our goal was to calculate accumulated growing degree days (GDD) from existing datasets collected for eastern gamagrass forage production experiments in northwestern Oklahoma, and discuss the use of GDD, instead of calendar harvest dates, in the production of eastern gamagrass forage. Growing degree days were calculated from 1 January each year using the “optimum day method”. For 10 harvest years, the first eastern gamagrass harvest required 690 ± 26 cumulative GDD. Based on long-term weather data from Woodward, Oklahoma, this would place the first harvest on or near 1 June. The second harvest required 635 ± 27 cumulative GDD which would place the second harvest on or near 15 July and the third harvest required 690 ± 23 cumulative GDD placing it on or near 30 August. Each of the 30 harvest required an average of 670 ± 15 cumulative GDD. Using GDD to predict harvest events is a useful tool that forage producer can use in the production of eastern gamagrass forage in the USA and possibly elsewhere.

Territory Characteristics of Cassin's Sparrows in Northwestern Oklahoma

We examined Cassin's sparrow (Aimophila cassinii) territory characteristics in shrub-grassland in northwestern Oklahoma during the 2008 breeding season. We estimated Cassin's sparrow territory area using territory mapping and song playback. Additionally, we determined vegetation cover, and aspect within territories and at nonterritorial sites, at both small scale (214 ha) and large scale (4856 ha). Mean territory size was 0.55 ha. Territories were 1.8 × more likely to be on north aspects than expected. Additionally, territories had greater shrub [sand sagebrush (Artemisia filifolia)] cover than the surrounding landscape.

Declines in pinyon pine cone production associated with regional warming

Global climate change is expected to produce large shifts in vegetation distribution and has already increased tree mortality, altering forest structure. However, long‐term shifts will be partly dependent on the ability of species to reproduce under a novel climate. Few studies have examined the impact of climate change on the reproductive output of long‐lived ‘masting' species, or species characterized by episodic reproductive events. Here, we show that seed cone production among pinyon pine (Pinus edulis), a masting species, declined by 40% from the 1974 decade (1969–1978) to the 2008 decade (2003–2012) in revisited stands throughout New Mexico and northwestern Oklahoma. Seed cone production was highly correlated with late summer temperatures at the time of cone initiation. Further, declines in seed cone production were greatest among populations that experienced the greatest increases in growing season temperatures, which were the populations located at the cooler, upper elevations. As growing season temperatures are predicted to increase across this region over the next century, these findings suggest seed cone production may be an increasingly important bottleneck for future pinyon pine regeneration, especially in areas with greater increases in temperature. Declines in seed cone production may not only affect pinyon pine population dynamics but also the various wildlife species that rely on pinyon pine seeds. Because pinyon pine has similar reproductive strategies as other semi‐arid pine species, increasing temperature may negatively influence reproductive output of other conifers. Further investigation into the full geographic and taxonomic extent of these seed declines is warranted.

Vascular Flora of Alabaster Caverns State Park, Cimarron Gypsum Hills, Woodward County,Oklahoma

Alabaster Caverns State Park is located in the Cimarron Gypsum Hills of northwestern Oklahoma, a semi-arid region of the state. The majority of the park is dominated by mixed-grass prairie and gypsum outcrops, with some riparian habitat and wooded north-facing slopes. A vascular plant inventory conducted from 2004 through 2007 yielded 274 species in 199 genera and 66 families. The largest families were the Poaceae (52 species), Asteraceae (47), and Fabaceae (23). There were 100 annuals, 6 biennials, and 163 perennials, as well as 5 species that have more than one life history form. Forty-two species (15.3%) were not native to North America. Three taxa currently being tracked by the Oklahoma Natural Heritage Inventory (2012) were present: Echinocereus reichenbachii (S3G5), Haploesthes greggii (S1G4?), and Marsilea vestita (S1G5). Compared to floristic inventories of sites in the Cimarron Gypsum Hills that are less impacted by public visitation, but more intensively grazed, Alabaster Caverns State Park has a higher number of species as well as a higher proportion of introduced species.

Patterns of size change in late Neogene pocket gophers from the Meade Basin of Kansas and Oklahoma

A dense late Neogene history of pocket gophers from the Meade Basin of south-western Kansas and north-western Oklahoma preserves a detailed record of size change, as indicated by mean length of the lower fourth premolar. A ‘time for space substitution’ interpretation results in the tentative recognition of a pattern analogous to character displacement, in which the small to medium-sized Pliogeomys buisi, P. louderbachi, Geomys minor and G. floralindae are considered ecological analogues and treated as a single ecological entity, Avatar A. The larger G. jacobi and G. quinni are combined as Avatar B. Statistical analyses confirm that populations of Avatar A are of equal size when allochronic from Avatar B, and significantly smaller when synchronic (and sympatric) with Avatar B. However, this pattern is complicated by the observation that Avatar A began dwarfing before the appearance of Avatar B. This historical perspective suggests that static size patterns among modern taxa may have a complex history. Occasional diminutive geomyid transients (G. adamsi, Thomomys cf talpoides) are always paired with significantly larger, medium-sized Geomys. Although a random walk explanation for the pattern of size changes is unlikely, we are currently unable to distinguish between environmental change and competition as the likely forcing mechanisms.

Badger Hole: Towards Defining a Folsom Bison Hunting Complex along the Beaver River, Oklahoma

Badger Hole, 34HP 194, is a Folsom-age arroyo bison kill along the north side of the Beaver River floodplain in northwestern Oklahoma. Badger Hole joins the Cooper and Jake Bluff sites to define one of the highest density Folsom site concentrations in this area of the southern Plains. Together these sites suggest the possible existence of a bison hunting complex that is structured on bison migration, arroyo occurrence, and seasonally specific intercept patterns. A preliminary definition of the Beaver River bison hunting complex is provided based on recent results of limited excavation at the recently discovered Badger Hole site.

Establishing Chickasaw plum for wildlife in northwestern Oklahoma

AbstractChickasaw plum (Prunus angustifolia) provides cover (escape, thermal, nesting, resting) and food (foliage and fruit) for wildlife in the southern Great Plains. Establishing plum may increase abundance of some wildlife species and species diversity on areas deficient in woody cover. To provide recommendations for establishment methods of Chickasaw plum, we tested effects of tillage, planting date, and competition control on survival and growth of bare‐root seedlings (BRS), coppiced transplants (CT), and intact transplants (IT) of Chickasaw plum planted on sandy sites in Woods County, Oklahoma, USA, during 2007–2011. Tillage did not affect survival or growth. After 4 years, BRS had higher survival than CT or IT (83%, 26%, and 18%, respectively). Bare‐root seedlings also outperformed transplants in height and diameter development and coppicing transplants did not have a long‐term negative effect. At the end of 4 years, heights were 70 cm, 55 cm, and 52 cm, while ground line diameters were 14 mm, 9 mm, and 9 mm, for the BRS, IT, and CT propagules, respectively. Based on crown spread and an initial planting density of 60 × 60 cm, stands should be fully established by age 6. Planting in mid‐spring increased survival of CT by >33% compared to late‐winter or early spring planting. Competition control using weed‐barrier cloth increased plum survival by 13%. Overall, BRS performed well, but if seedlings are not available, local transplants can be taken and planted at higher densities to achieve similar results. If using local transplants, we recommend coppicing to increase survival and hasten establishment. © 2012 The Wildlife Society.

Modelling the response of an alluvial aquifer to anthropogenic and recharge stresses in the United States Southern Great Plains

This paper uses Visual MODFLOW to simulate potential impacts of anthropogenic pumping and recharge variability on an alluvial aquifer in semi-arid northwestern Oklahoma. Groundwater withdrawal from the aquifer is projected to increase by more than 50% (relative to 1990) by the year 2050. In contrast, climate projections indicate declining regional precipitation over the next several decades, creating a potential problem of demand and supply. The following scenarios were simulated: (1) projected groundwater withdrawal, (2) a severe drought, (3) a prolonged wet period, and (4) a human adjustment scenario, which assumes future improvements in water conservation measures. Results indicate that the combined impacts of anthropogenic pumping and droughts would create drawdown of greater than 12 m in the aquifer. Spatially, however, areas of severe drawdown will be localized around large-capacity well clusters. The worst impacts of both pumping and droughts will be on stream–aquifer interaction. For example, the projected aquifer pumpage would lead to a total streamflow loss of 40%, creating losing stream system regionally. Similarly, a severe drought would lead to a total streamflow loss of >80%. A post-audit of the model was also carried out to evaluate model performance. By simulating various stress scenarios on the alluvial aquifer, this study provides important information for evaluating management options for alluvial aquifers.

Five million years of pocket gopher history in the Meade Basin of southwestern Kansas and northwestern Oklahoma

ABSTRACT The Meade Basin record of pocket gophers extends from the latest Miocene (Buis Ranch local fauna) to modern time. A primitive species with hypsodont but rooted cheek teeth, Pliogeomys buisi, characterizes the late Hemphillian. Another species of Pliogeomys, P. louderbachi, is described here as a new species from the early Blancan. It is intermediate in dental and mandibular morphology between Pliogeomys and Geomys. The Geomys minor (= G. smithi) lineage displays a stepped dwarfing trend prior to its extinction, whereas the G. jacobi lineage demonstrates an overall pattern of stasis in size. G. jacobi is replaced by G. quinni at the end of the Pliocene, within which there is a significant directional size increase. A late Pliocene immigrant, the new species G. floralindae, appears in the Sanders assemblage. It is briefly replaced by an indeterminate small species in the Nash 72 local fauna. G. tobinensis is found in the Cudahy local fauna. Morphologically modern G. bursarius appears in the Meade Basin during the early Rancholabrean. A small, primitive species, Geomys adamsi, appears only during the early Pliocene at Fox Canyon, and transient Thomomys appear at various times during the Pleistocene, both apparently during cold intervals. A phylogenetic analysis suggests two clades, one uniting Pliogeomys russelli and Geomys adamsi and another including the remaining Meade Basin geomyines. Enhanced species turnover and the last push for modern mandibular morphology is most pronounced in sediments younger than about 2.6 million years ago, corresponding to the first global cooling heralding the Pleistocene.