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Sample records for american southwest desert

  1. Disturbance and Plant Succession in the Mojave and Sonoran Deserts of the American Southwest

    PubMed Central

    Abella, Scott R.

    2010-01-01

    Disturbances such as fire, land clearing, and road building remove vegetation and can have major influences on public health through effects on air quality, aesthetics, recreational opportunities, natural resource availability, and economics. Plant recovery and succession following disturbance are poorly understood in arid lands relative to more temperate regions. This study quantitatively reviewed vegetation reestablishment following a variety of disturbances in the Mojave and Sonoran Deserts of southwestern North America. A total of 47 studies met inclusion criteria for the review. The time estimated by 29 individual studies for full reestablishment of total perennial plant cover was 76 years. Although long, this time was shorter than an estimated 215 years (among 31 individual studies) required for the recovery of species composition typical of undisturbed areas, assuming that recovery remains linear following the longest time since disturbance measurement made by the studies. PMID:20617030

  2. 75 FR 57761 - Desert Southwest Power, LLC; Notice of Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-22

    ... Energy Regulatory Commission Desert Southwest Power, LLC; Notice of Filing September 14, 2010. Take notice that on September 10, 2010, Desert Southwest Power, LLC (Desert Southwest) filed responses to the... Commission's July 28, 2010 letter regarding Desert Southwest's petition for declaratory order...

  3. Desert basins of the Southwest

    USGS Publications Warehouse

    Leake, Stanley A.; Konieczki, Alice D.; Rees, Julie A.H.

    2000-01-01

    Ground water is among the Nation’s most important natural resources. It provides drinking water to urban and rural communities, supports irrigation and industry, sustains the flow of streams and rivers, and maintains riparian and wetland ecosystems. In many areas of the Nation, the future sustainability of ground-water resources is at risk from overuse and contamination. Because ground-water systems typically respond slowly to human actions, a long-term perspective is needed to manage this valuable resource. This publication is one in a series of fact sheets that describe ground-water-resource issues across the United States, as well as some of the activities of the U.S. Geological Survey that provide information to help others develop, manage, and protect ground-water resources in a sustainable manner. Ground-water resources in the Southwest are among the most overused in the United States. Natural recharge to aquifers is low and pumping in many areas has resulted in lowering of water tables. The consequences of large-scale removal of water from storage are becoming increasingly evident. These consequences include land subsidence; loss of springs, streams, wetlands and associated habitat; and degradation of water quality. Water managers are now seeking better ways of managing ground-water resources while looking for supplemental sources of water. This fact sheet reviews basic information on ground water in the desert basins of the Southwest. Also described are some activities of the U.S. Geological Survey (USGS) that are providing scientific information for sustainable management of ground-water resources in the Southwest. Ground-water sustainability is defined as developing and using ground water in a way that can be maintained for an indefinite time without causing unacceptable environmental, economic, or social consequences.

  4. Collection Development "Southwest Gardening": The Desert Shall Bloom

    ERIC Educational Resources Information Center

    Charles, John; Mosley, Shelley; Van Winkle, Sandra

    2008-01-01

    Gardening in the American Southwest (SW) is an extreme sport. Not only are gardeners challenged by geographic extremes from tropical deserts to subalpine locales, they must also deal with a wide range of climates. Winter in the mountains and higher regions means heavy snows, frozen soils, and temperatures that can dip below zero. In contrast,…

  5. 75 FR 61467 - Desert Southwest Power, LLC; Notice of Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-05

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Desert Southwest Power, LLC; Notice of Filing September 27, 2010. Take notice that on September 24, 2010, Desert Southwest Power, LLC (Desert Southwest) supplemented...

  6. Desert Culture Area. Native American Curriculum Series.

    ERIC Educational Resources Information Center

    Ross, Cathy; Fernandes, Roger

    One in a series of Native American instructional materials, this booklet introduces elementary students to the history and culture of the Navajo, Pueblo, and other Indian tribes of the southwest desert. Written in simple language, the booklet provides background information, activities, legends, and illustrations. Topics include the climate of the…

  7. Perspectives on history: army dietetics in southwest Asia during Operation Desert Shield/Desert Storm.

    PubMed

    Hodges, P A; Lyon, J M

    1996-06-01

    The Army dietitians deployed during Operation Desert Shield and Operation Desert Storm exemplified the commitment, dedication, patriotism, and professionalism of their predecessors. Although some were continuously on the move and all dealt with the extremes of a desert environment, were frequently handicapped with equipment shortages, and coped constantly with the monotony of limited ration variety, throughout their experiences these professionals expressed pride in participating in this national undertaking. The purposes of this article are to familiarize members of The American Dietetic Association with the responses of their colleagues in the US military to another of their nation's calls, to relate some aspects of Army dietetics experienced in Southwest Asia, and to identify the lessons learned in that engagement. PMID:8655908

  8. 76 FR 28767 - Desert Southwest Customer Service Region-Rate Order No. WAPA-152

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-18

    ... Area Power Administration Desert Southwest Customer Service Region-Rate Order No. WAPA-152 AGENCY.... FOR FURTHER INFORMATION CONTACT: Mr. Darrick Moe, Regional Manager, Desert Southwest Customer Service... moe@wapa.gov , or Mr. Jack Murray, Rates Manager, Desert Southwest Customer Service Region,...

  9. Dramatic Demand Reduction In The Desert Southwest

    SciTech Connect

    Boehm, Robert; Hsieh, Sean; Lee, Joon; Baghzouz, Yahia; Cross, Andrew; Chatterjee, Sarah

    2015-07-06

    This report summarizes a project that was funded to the University of Nevada Las Vegas (UNLV), with subcontractors Pulte Homes and NV Energy. The project was motivated by the fact that locations in the Desert Southwest portion of the US demonstrate very high peak electrical demands, typically in the late afternoons in the summer. These high demands often require high priced power to supply the needs, and the large loads can cause grid supply problems. An approach was proposed through this contact that would reduce the peak electrical demands to an anticipated 65% of what code-built houses of the similar size would have. It was proposed to achieve energy reduction through four approaches applied to a development of 185 homes in northwest part of Las Vegas named Villa Trieste. First, the homes would all be highly energy efficient. Secondly, each house would have a PV array installed on it. Third, an advanced demand response technique would be developed to allow the resident to have some control over the energy used. Finally, some type of battery storage would be used in the project. Pulte Homes designed the houses. The company considered initial cost vs. long-term savings and chose options that had relatively short paybacks. HERS (Home Energy Rating Service) ratings for the homes are approximately 43 on this scale. On this scale, code-built homes rate at 100, zero energy homes rate a 0, and Energy Star homes are 85. In addition a 1.764 Wp (peak Watt) rated PV array was used on each house. This was made up of solar shakes that were in visual harmony with the roofing material used. A demand response tool was developed to control the amount of electricity used during times of peak demand. While demand response techniques have been used in the utility industry for some time, this particular approach is designed to allow the customer to decide the degree of participation in the response activity. The temperature change in the residence can be decided by the residents by

  10. Health Oasis in the Desert Southwest.

    ERIC Educational Resources Information Center

    Barrett, Julia R.

    2001-01-01

    Community outreach and education at the Southwest Environmental Health Sciences Center (University of Arizona, Tucson) features a Web site on toxicology and environmental health with resources for secondary teachers and students, an integrated high school curriculum with an environmental health sciences theme, teacher workshops, outreach to…

  11. Chemical mass balance source apportionment of fine and PM10 in the Desert Southwest, USA

    EPA Science Inventory

    The Desert Southwest Coarse Particulate Matter Study was undertaken in Pinal County, Arizona, to better understand the origin and impact of sources of fine and coarse particulate matter (PM) in rural, arid regions of the U.S. southwestern desert. The desert southwest experiences ...

  12. Notes from the Great American Desert

    ERIC Educational Resources Information Center

    Grady, Marilyn L.; LaCost, Barbara Y.

    2005-01-01

    In the good old days, the state that is Nebraska was identified as part of the Great American Desert. In many ways, in climate and terrain, it still bears a resemblance to a desert. As a frontier or a land of pioneers, it deserves recognition. Invisibility may be one of the greatest challenges women face. One of the great flaws in the writing of…

  13. Geology of the American Southwest

    NASA Astrophysics Data System (ADS)

    Baldridge, W. Scott

    2004-06-01

    Scott Baldridge presents a concise guide to the geology of the Southwestern U.S. Two billion years of Earth history are represented in the rocks and landscape of the Southwest U.S., creating natural wonders such as the Grand Canyon, Monument Valley, and Death Valley. This region is considered a geologist's "dream", attracting a large number of undergraduate field classes and amateur geologists. The volume will prove invaluable to students and will also appeal to anyone interested in the geology and landscape of the region's National Parks.

  14. American Indians of the Southwest.

    ERIC Educational Resources Information Center

    Dutton, Bertha P.

    Designed for both the specialist and nonspecialist, the book provides a synthesis of Southwestern Indian culture based on long familiarity with the people. Chapter 1 describes the physical aspects of American Indians, land and Aboriginal inhabitants, and development of socio-religious patterns. Chapter II is about Pueblo Peoples (Tanoans,…

  15. Historic American Buildings Survey Marc Blair Photographer, Summer 1966 SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Historic American Buildings Survey Marc Blair Photographer, Summer 1966 SOUTHWEST INTERIOR DETAIL - Grace Protestant Episcopal Church, 1041 Wisconsin Avenue Northwest, Washington, District of Columbia, DC

  16. Chemical Characterization of Coarse Particulate Matter in the Desert Southwest - Pinal County Arizona, USA

    EPA Science Inventory

    The Desert Southwest Coarse Particulate Matter Study was undertaken of ambient concentrations and the composition of fine and coarse particles in rural, arid environments. Sampling was conducted in Pinal County, Arizona between February 2009 and February 2010. The goals of this ...

  17. 75 FR 18203 - Desert Southwest Power, LLC; Notice of Petition for Declaratory Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-09

    ... Transmission Investment Through Pricing Reform, Order No. 679, 71 FR 43294 (July 31, 2006), FERC Stats. & Regs. ] 31,222 (2006), order on reh'g, Order No. 679-A, 72 FR 1152 (Jan. 10, 2007), FERC Stats. & Regs. ] 31... Energy Regulatory Commission Desert Southwest Power, LLC; Notice of Petition for Declaratory Order...

  18. Hydrogeologic factors that influence ground water movement in the desert southwest United States

    USGS Publications Warehouse

    Chuang, Frank C.; McKee, Edwin H.; Howard, Keith A.

    2003-01-01

    A project to study ground-water and surface-water interactions in the desert southwestern United States was initiated in 2001 by the Tucson, Arizona office of the Water Resources Division, U.S. Geological Survey (USGS). One of the goals of the Southwest Ground-water Resources Project was to develop a regional synthesis that includes the use of available digital geologic data, which is growing rapidly due to the increasing use of Geographic Information Systems (GIS). Included in this report are the digital maps and databases of geologic information that should have a direct impact on the studies of ground-water flow and surface-water interaction. Ground-water flow is governed by many geologic factors or elements including rock and soil permeability, stratigraphy and structural features. These elements directly influence ground-water flow, which is key to understanding the possible inter-connectivity of aquifer systems in desert basins of the southwestern United States. We derive these elements from the evaluation of regional geology and localized studies of hydrogeologic basins. These elements can then be applied to other unstudied areas throughout the desert southwest. This report presents a regional perspective of the geologic elements controlling ground-water systems in the desert southwest that may eventually lead to greater focus on smaller sub-regions and ultimately, to individual ground-water basins.

  19. High Temperature Extremes - Will They Transform Structure of Avian Assemblages in the Desert Southwest?

    NASA Astrophysics Data System (ADS)

    Mutiibwa, D.; Albright, T. P.; Wolf, B. O.; Mckechnie, A. E.; Gerson, A. R.; Talbot, W. A.; Sadoti, G.; O'Neill, J.; Smith, E.

    2014-12-01

    Extreme weather events can alter ecosystem structure and function and have caused mass mortality events in animals. With climate change, high temperature extremes are increasing in frequency and magnitude. To better understand the consequences of climate change, scientists have frequently employed correlative models based on species occurrence records. However, these approaches may be of limited utility in the context of extremes, as these are often outside historical ranges and may involve strong non-linear responses. Here we describe work linking physiological response informed by experimental data to geospatial climate datasets in order to mechanistically model the dynamics of dehydration risk to dessert passerine birds. Specifically, we modeled and mapped the occurrence of current (1980-2013) high temperature extremes and evaporative water loss rates for eight species of passerine birds ranging in size from 6.5-75g in the US Southwest portion of their range. We then explored the implications of a 4° C warming scenario. Evaporative water loss (EWL) across a range of high temperatures was measured in heat-acclimated birds captured in the field. We used the North American Land Data Assimilation System 2 dataset to obtain hourly estimates of EWL with a 14-km spatial grain. Assuming lethal dehydration occurs when water loss reaches 15% of body weight, we then produced maps of total daily EWL and time to lethal dehydration based on both current data and future scenarios. We found that milder events capable of producing dehydration in passerine birds over four or more hours were not uncommon over the Southwest, but rapid dehydration conditions (<3 hours) were rare. Under the warming scenario, the frequency and extent of dehydration events expanded greatly, often affecting areas several times larger than in present-day climate. Dehydration risk was especially high among smaller bodied passerines due to their higher mass-specific rates of water loss. Even after

  20. Historical context and ecological impact of the 1950s drought in the American Southwest

    SciTech Connect

    Betancourt, J.L.; Pierson, E.A. )

    1993-06-01

    In the American Southwest, the 1950s drought caused massive vegetation dieoffs from the lowland deserts well into conifer woodlands of the uplands, resetting demographic clocks and creating disequilibria in carbon and nutrient cycling. Climate reconstructions from tree rings indicate up to 500-year return periods for droughts of similar magnitude. Broadscale mortality of long-lived conifers yielded >100 m elevational shifts in ecotonal boundaries that had been stable for at least 2500 years, according to a high-resolution packrat midden record. The drought also may have accelerated recent invasion of shurblands into grasslands, and the northward and upward expansion of xerophytes such as Larrea tridentata. Long-term monitoring efforts in the Southwest, particularly those contemplated or initiated only recently (e.g., 1988 on the Sevilleta LTER, New Mexico), should consider the imprint of the 1950s drought on present and future vegetation dynamics.

  1. Identification of skunk species submitted for rabies testing in the desert southwest.

    PubMed

    Dragoo, Jerry W; Matthes, Daniel K; Aragon, Adam; Hass, Christine C; Terry, L Yates

    2004-04-01

    Skunks usually are identified by their common name (skunk) when submitted for rabies testing. In the desert southwest (Arizona, New Mexico, Texas, USA; and northern Mexico), there are five species of skunks; four of which can occur in sympatry. To better understand the ecology of skunk rabies in these areas, it is imperative that species be properly identified. We used the displacement loop (d-loop) of the mitochondrial genome to identify to species 24 skunk brain samples submitted for rabies testing in New Mexico from 2001 to 2002. Most were identified as striped skunks (Mephitis mephitis), but hooded (Mephitis macroura) and hog-nosed (Conepatus leuconotus) skunks were also found.

  2. Mexican-Americans in the Southwest.

    ERIC Educational Resources Information Center

    Martinez, Reynaldo L.; And Others

    Of the 10 million Mexican Americans in the United States, 90% reside in the southwestern states of California, Colorado, Arizona, New Mexico and Texas. Historically, the acquisition of Spanish speaking citizens by the U.S. has resulted from military conquest. Yet, Mexican Americans did not have a significant political voice until the high fatality…

  3. Mexican Americans: Sons of the Southwest.

    ERIC Educational Resources Information Center

    Lamb, Ruth S.

    Concerned with the Mexican Americans, who constitute the largest ethnic group in the southwestern United States, this book traces the history of these people from the early explorations and colonizing efforts of the Spanish in North and South America during the 16th century to the present. Major divisions of this book are the Introduction,…

  4. Size-Differentiated Chemical Composition of Re-Suspended Soil Dust from the Desert Southwest United States

    EPA Science Inventory

    As part of the Desert Southwest Coarse Particulate Matter Study which characterized the composition of fine and coarse particulate matter in Pinal County, AZ, several source samples were collected from several different soil types to assist in source apportionment analysis of the...

  5. MEXICAN-AMERICAN STUDY PROJECT. ADVANCE REPORT 10, MEXICAN AMERICANS IN SOUTHWEST LABOR MARKETS.

    ERIC Educational Resources Information Center

    FOGEL, WALTER

    MEXICAN AMERICANS ARE CLEARLY A DISADVANTAGED GROUP IN THE LABOR MARKETS OF THE SOUTHWEST. ALTHOUGH SUBSTANTIAL GAINS IN INCOME AND OCCUPATIONAL STATUS TAKE PLACE BETWEEN THE FIRST AND SECOND GENERATIONS OF MEXICAN AMERICANS, LITTLE IMPROVEMENT IS EVIDENCED AFTER THE SECOND GENERATION. AS FURTHER EVIDENCE OF DISADVANTAGEMENT, IT HAS BEEN FOUND…

  6. Evidence of Aqueous Secondary Organic Aerosol Formation from Biogenic Emissions in the North American Sonoran Desert

    NASA Astrophysics Data System (ADS)

    Sorooshian, A.; Youn, J.; Wang, Z.; Wonaschuetz, A.; Arellano, A. F.; Betterton, E. A.

    2013-12-01

    This study examines the role of aqueous secondary organic aerosol (SOA) formation in the North American Sonoran Desert as a result of intense solar radiation, enhanced moisture, and biogenic volatile organic compounds (BVOCs). The ratio of water-soluble organic carbon (WSOC) to organic carbon (OC) nearly doubles during the monsoon season relative to other seasons of the year. When normalized by mixing height, the WSOC enhancement during monsoon months relative to preceding dry months (May - June) exceeds that of sulfate by nearly a factor of ten. WSOC:OC and WSOC are most strongly correlated with moisture parameters, temperature, and concentrations of ozone and BVOCs. No positive relationship was identified between WSOC or WSOC:OC and anthropogenic tracers such as carbon monoxide over a full year. These results are especially of significance as recent modeling studies suggest that aqueous SOA formation is geographically concentrated in the eastern United States and likely unimportant in other areas such as the Southwest.

  7. 1. Historic American Buildings Survey Nathaniel R. Ewan, Photographer July ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Nathaniel R. Ewan, Photographer July 12, 1936 EXTERIOR - ENAMELING HOUSE - SOUTHWEST ELEVATION - The Deserted Village, Enameling House, Allaire, Monmouth County, NJ

  8. IPM for fresh-market lettuce production in the desert southwest: the produce paradox.

    PubMed

    Palumbo, John C; Castle, Steven J

    2009-12-01

    In the 'Integrated Control Concept', Stern et al. emphasized that, although insecticides are necessary for agricultural production, they should only be used as a last resort and as a complement to biological control. They argued that selective insecticide use should only be attempted after it has been determined that insect control with naturally occurring biotic agents is not capable of preventing economic damage. However, they concluded their seminal paper by emphasizing that integrated control will not work where natural enemies are inadequate or where economic thresholds are too low to rely on biological control. Thus, it is no surprise that insect control in high-value, fresh-market lettuce crops grown in the desert southwest have relied almost exclusively on insecticides to control a complex of mobile, polyphagous pests. Because lettuce and leafy greens are short-season annual crops with little or no tolerance for insect damage or contamination, biological control is generally considered unacceptable. High expectations from consumers for aesthetically appealing produce free of pesticide residues further forces vegetable growers to use chemical control tactics that are not only effective but safe. Consequently, scientists have been developing integrated pest management (IPM) programs for lettuce that are aimed at reducing the economic, occupational and dietary risks associated with chemical controls of the past. Most of these programs have drawn upon the integrated control concept and promote the importance of understanding the agroecosystem, and the need to sample for pest status and use action thresholds for cost-effective insect control. More recently, pest management programs have implemented newly developed, reduced-risk chemistries that are selectively efficacious against key pests. This paper discusses the influence that the integrated control concept, relative to zero-tolerance market standards and other constraints, has had on the adoption of pest

  9. 76 FR 59682 - Desert Southwest Customer Service Region-Western Area Lower Colorado Balancing Authority-Rate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-27

    ..., DSW-EI2, DSW- SPR2, and DSW-SUR2 on June 26, 2006 (Rate Order No. WAPA-127, 71 FR 36332).\\1\\ These..., Extension of Rate Order No. WAPA-127 through September 30, 2013. 76 FR 28767, May 18, 2011. Desert Southwest... published on September 18, 1985 (50 FR 37835). Under Delegation Order Nos. 00-037.00 and 00-001.00C, 10...

  10. Climate scenarios for the American Southwest in the next century

    SciTech Connect

    Diaz, H.F.

    1995-12-31

    The climate of the Southwest US is governed by two separate large-scale regimes during the course of the year. In the winter half-year, disturbances in the westerlies supply 40--80% of the annual total precipitation in the region. The precipitation is associated with frontal systems sweeping from the west and north through the area, and with the development of upper level troughs and occasional cutoff lows in the upper atmosphere. During the summer half-year, and particularly during the months of July--September, a monsoonal-type circulation system develops along western Mexico and extends into the desert areas of the US Southwest producing locally heavy thunderstorms and floods. In early fall, eastern Pacific hurricanes, occasionally recurving to the north and east across northwestern Mexico, can also produce widespread rains and locally severe flooding in the region. With regards to future changes in climate forced by increasing atmospheric greenhouse-gas concentrations, the question arises, as to whether the annual precipitation in the region will be more affected by changes in the winter-time regime, that is, through a modification of the polar jet stream and associated extratropical cyclone tracks, or whether an increase in the summer monsoon system will, at least in part, make up for a potential winter decline in precipitation. An increase in convective summer-season rainfall will also be accompanied by enhanced soil erosion, arroyo cutting, greater sediment loads in the region`s streams, and other problems. Climatic changes resulting from the enhanced greenhouse effect will be superimposed on a rich spectrum of naturally occurring climatic variability at the relevant time scales that are of interest here, namely, decadal to century fluctuations.

  11. Development of a relative paleointensity curve for the American Southwest

    NASA Astrophysics Data System (ADS)

    Jones, S. A.; Tauxe, L.; Genevey, A.; Blinman, E.

    2014-12-01

    Paleointensity experiments were conducted using the IZZI protocol on fifty-seven baked pottery fragments collected from nine archeological sites near Santa Fe, New Mexico. Results from seventeen fragments passed our strict selection criteria and indicate that at least seven distinct age intervals may be present. Stylistic evidence, historical documentation, dendrochronology, and 14C analyses provide age constraints with up to decade resolution for the results. Continued IZZI paleointensity experiments will be conducted on the seventeen promising fragments, including anisotropy and cooling rate corrections, to ensure a robust dataset. Moreover, additional pottery fragments from the New Mexico area will be analyzed for paleointensity in hopes of combining the data sets to create a high-resolution paleointensity curve for the recent archeological time in the American Southwest.

  12. Water-use trends in the desert southwest--1950-2000

    USGS Publications Warehouse

    Konieczki, Alice D.; Heilman, Julie A.

    2004-01-01

    The population of the Desert Southwest is among the fastest growing in the country. In this area, ground-water supplies have been developed, surface-water resources have been fully appropriated, and conservation and conjunctive water-use measures are being used to meet water-resource needs. Complex networks of water-distribution systems have been developed to deliver surface-water supplies, and interstate agreements, such as the Colorado River Compact of 1922, help manage the distribution of water among many States in the Western United States, including Arizona, California, Nevada, New Mexico, and Utah. The Colorado River, which lies on the borders of Arizona, California, and Nevada, plays an important role in supplying water to the Southwest. Water from the Colorado River is used to irrigate extensive farmland in the southern California deserts and is delivered to southern and central Arizona through the Central Arizona Project canal for domestic and agricultural uses. It is also the source of much of the water used for domestic purposes in southern Nevada. Estimated water-withdrawal and related data were compiled from various sources to identify trends in Arizona, California, Nevada, New Mexico, and Utah. More water is used for agriculture than domestic and industrial use in these five States. From 1950 to 2000, however, the percentage increase in withdrawal for domestic water use exceeded that for agricultural use. The estimated amount of water withdrawn for domestic, agricultural, and industrial purposes in Arizona, California, Nevada, New Mexico, and Utah increased 58 percent, from 39.6 to 62.8 million acre-feet, from 1950 to 2000. During this period withdrawals for domestic water use, which included self-supplied domestic and public supply (all deliveries to residential, commercial, and some industrial users), increased 410 percent from 2.0 million to 10.2 million acre-feet and the population in these five Southwestern States increased 250 percent. From 1965

  13. Middle to late cenozoic geology, hydrography, and fish evolution in the American Southwest

    USGS Publications Warehouse

    Spencer, J.E.; Smith, G.R.; Dowling, T.E.

    2008-01-01

    An evaluation of the poorly understood Cenozoic hydrologic history of the American Southwest using combined geological and biological data yields new insights with implications for tectonic evolution. The Mesozoic Cordilleran orogen next to the continental margin of southwestern North America probably formed the continental divide. Mountain building migrated eastward to cause uplift of the Rocky Mountains during the Late Cretaceous to early Tertiary Laramide orogeny. Closed drainage basins that developed between the two mountain belts trapped lake waters containing fish of Atlantic affinity. Oligocene-Miocene tectonic extension fragmented the western mountain belt and created abundant closed basins that gradually filled with sediments and became conduits for dispersal of fishes of both Pacific and Atlantic affinity. Abrupt arrival of the modern Colorado River to the Mojave-Sonora Desert region at ca. 5 Ma provided a new conduit for fish dispersal. Great dissimilarities in modern fish fauna, including differences in their mitochondrial deoxyribonucleic acid (DNA), indicate that late Miocene runoff from the Colorado Plateau did not flow down the Platte or Rio Grande, or through the Lake Bonneville Basin. Fossil fishes from the upper Miocene part of the Bidahochi Formation on the Colorado Plateau have characteristics that reflect a habitat of large, swift-moving waters, and they are closely related to fossil fishes associated with the Snake and Sacramento Rivers. This evidence suggests that influx of fishes from the ancestral Snake River involved a major drainage, not merely small headwater transfers. ?? 2008 The Geological Society of America.

  14. South American mammal zoogeography: evidence from convergent evolution in desert rodents.

    PubMed

    Mares, M A

    1975-05-01

    Current theories regarding colonization of South America by mammals are divided between those supported by fossil evidence, which suggest the original mammal fauna of the isolated continent was augmented by early immigrants (primates, caviomorph rodents, and later, procyonids) with a final large influx of northern mammals occurring with the formation of the Panama land bridge, and an opposing view which states that the purported "recent invaders" are too taxonomically and ecologically differentiated to have colonized since the land bridge arose. The second theory suggests that most extant mammals entered before the Plio-Pleistocene land connection. An analysis of degree of physiological adaptation, natural history, distribution patterns, and a multivariate assessment of convergent evolution of Monte Desert rodents indicate that South American cricetine rodents are not highly specialized for desert life. Their degree of adaptation could be accounted for, in large part, by adaptations for arid or semiarid Andean habitats. No Monte Desert rodent has developed the specialized desert traits that have evolved in most desert rodent faunas of the world, although extinct marsupials similar to living bipedal desert rodents were present in the Monte as recently as late Pliocene. Evidence suggests that Monte caviomorphs have been associated with the desert for a longer period than cricetines, and that the latter represent a fairly recent invasion of the Monte Desert. The data thus support the first hypothesis of South American mammal colonization.

  15. Subsidence (2004-2009) in and near lakebeds of the Mojave River and Morongo groundwater basins, southwest Mojave Desert, California

    USGS Publications Warehouse

    Solt, Mike; Sneed, Michelle

    2014-01-01

    Subsidence, in the vicinity of dry lakebeds, within the Mojave River and Morongo groundwater basins of the southwest Mojave Desert has been measured by Interferometric Synthetic Aperture Radar (InSAR). The investigation has focused on determining the location, extent, and magnitude of changes in land-surface elevation. In addition, the relation of changes in land-surface elevation to changes in groundwater levels and lithology was explored. This report is the third in a series of reports investigating land-surface elevation changes in the Mojave and Morongo Groundwater Basins, California. The first report, U.S. Geological Survey (USGS) Water-Resources Investigations Report 03-4015 by Sneed and others (2003), describes historical subsidence and groundwater-level changes in the southwest Mojave Desert from 1969 to 1999. The second report, U.S. Geological Survey Water-Resources Investigations Report 07-5097, an online interactive report and map, by Sneed and Brandt (2007), describes subsidence and groundwater-level changes in the southwest Mojave Desert from 1999 to 2004. The purpose of this report is to document an updated assessment of subsidence in these lakebeds and selected neighboring areas from 2004 to 2009 as measured by InSAR methods. In addition, continuous Global Positioning System (GPS)(2005-10), groundwater level (1951-2010), and lithologic data, if available, were used to characterize compaction mechanisms in these areas. The USGS California Water Science Center’s interactive website for the Mojave River and Morongo groundwater basins was created to centralize information pertaining to land subsidence and water levels and to allow readers to access available data and related reports online. An interactive map of land subsidence and water levels in the Mojave River and Morongo groundwater basins displays InSAR interferograms, subsidence areas, subsidence contours, hydrographs, well information, and water-level contours. Background information, including

  16. Mexican American Youth of the Southwest Borderlands: Perceptions of Ethnicity, Acculturation, and Race.

    ERIC Educational Resources Information Center

    Holleran, Lori K.

    2003-01-01

    A study examined young Mexican Americans' perspectives concerning their own ethnicity. Observations and focus groups with 30 Mexican American youths from a Southwest barrio indicate that respondents used racial terms to understand acculturation differences. Intense negative feelings were expressed about less- acculturated, Spanish-speaking…

  17. Phylogeography of Declining Relict and Lowland Leopard Frogs in the Desert Southwest of North America

    EPA Science Inventory

    We investigated the phylogeography of the closely related relict leopard frog (Rana onca) and lowland leopard frog (R. yavapaiensis) – two declining anurans from the warm-desert regions of southwestern North America. We used sequence data from two mitochondrial DNA genes to asses...

  18. Ephemeral-streamflow Induced Focused Recharge in the Desert Southwest (US)

    NASA Astrophysics Data System (ADS)

    Constantz, J. E.; Stonestrom, D. A.

    2015-12-01

    Multiyear studies examined meteorologic and hydrogeologic controls on ephemeral streamflow and focused groundwater recharge at 8 sites across arid and semiarid southwestern regions of the US. Intensive data collection targeted the Great Basin, Mojave Desert, Sonoran Desert, Rio Grande Rift, and Colorado Plateau physiographic areas (USGS Prof. Pap. 1703-C). During the study period (1997-2002), the region went from wetter than normal conditions associated with a strong El Niño climatic pattern (1997-1998) to drier than normal conditions associated with a La Niña climatic pattern. The 1997-1998 El Niño, the strongest in the modern instrumental record, roughly doubled precipitation at the Great Basin, Mojave Desert, and Colorado Plateau study sites. Precipitation at all sites thereafter trended sharply lower, producing moderate- to severe-drought conditions by the end of the study. Streamflow in regional rivers indicated diminishing groundwater recharge, with annual-flow volumes declining to levels of only 10-46% of their respective long-term averages by 2002. Local streamflows showed higher variability, reflecting smaller scales of integration (in time and space) within study-site watersheds. Toward the end of study, extended periods (9-15 months) of zero or negligible flow were observed at half the sites. Summer monsoonal rains generated the majority of streamflow and associated recharge in the Sonoran Desert sites and the more southerly Rio Grande Rift site, whereas winter storms and spring snowmelt dominated the northern and westernmost sites. Proximity to moisture sources and meteorologic fluctuations, in concert with orography, largely control the generation of focused groundwater recharge from ephemeral streamflow, although other aspects (geology, soil, and vegetation) were also identified as factors. Estimates of annual focused infiltration for the research sites ranged from about 105-107 cubic meters from contributing areas that ranged from 26-2,260 square

  19. The Effects of Incorporation into the World-System on Ethnic Persistence: The American Conquest of the Southwest.

    ERIC Educational Resources Information Center

    Hall, Thomas D.

    The varying results of incorporation on the survival of groups such as bands, tribes, chiefdoms and mercantile states can be explained by applying the historical process to the American conquest of the Southwest. The American Southwest (the region covered by Arizona, New Mexico, parts of Texas, California, Utah, Nevada, and Colorado) was occupied…

  20. Status Report on the "Wildfires and Invasive Plants in American Deserts" Symposium and Workshop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The “Wildfires and Invasive Plants in American Deserts” symposium and workshop, was held in Reno, Nevada on December 9-11, 2008. The purpose of this symposium was to synthesize the current understanding of the interactions of wildfire and invasive plants in the four U.S. deserts and the Colorado Pla...

  1. Mexican American Legal Heritage in the Southwest. Second Edition, 1974.

    ERIC Educational Resources Information Center

    Ruiz, Manuel, Jr.

    By 1920, 72 years after the Treaty of Guadalupe Hidalgo brought hostilities between Mexico and the United States to an end, Mexican American exclusion from virtually every area of participation in the mainstream of American life had become institutionalized. With two cultures in conflict and new political power at stake, a series of legal actions…

  2. The Effect of Neighborhood Context on the Drug Use of American Indian Youth of the Southwest

    PubMed Central

    Yabiku, Scott T.; Rayle, Andrea Dixon; Okamoto, Scott K.; Marsiglia, Flavio F.; Kulis, Stephen

    2011-01-01

    SUMMARY This study examined neighborhood effects on the drug use of American Indian youth of the Southwest. We compared these effects with American Indian and non-American Indian youth in order to examine the universality of neighborhood disorganization as a risk factor for drug use. Neighborhood level variables included unemployment, poverty, education, and violent crime rate. Results indicated that American Indian youth were not as adversely affected by these neighborhood factors. American Indian youth may possess cultural characteristics that protect them from the adverse effects of neighborhood disorganization, including close familial relationships and ethnic pride. Culturally competent practice with American Indian youth may best be implemented through the enhancement of relational and cultural strengths as described in the literature. PMID:18192210

  3. PLUTONIUM UPTAKE AND BEHAVIOR IN PLANTS OF THE DESERT SOUTHWEST: A PRELIMINARY ASSESSMENT

    SciTech Connect

    Caldwell, E.; Duff, M.; Ferguson, C.

    2011-03-01

    Eight species of desert vegetation and associated soils were collected from the Nevada National Security Site (N2S2) and analyzed for 238Pu and 239+240Pu concentrations. Amongst the plant species sampled were: atmospheric elemental accumulators (moss and lichen), the very slow growing, long-lived creosote bush and the rapidly growing, short-lived cheatgrass brome. The diversity of growth strategies provided insight into the geochemical behavior and bio-availability of Pu at the N2S2. The highest concentrations of Pu were measured in the onion moss (24.27 Bq kg-1 238Pu and 52.78 Bq kg-1 239+240Pu) followed by the rimmed navel lichen (8.18 Bq kg-1 and 18.4 Bq kg-1 respectively), pointing to the importance of eolian transport of Pu. Brome and desert globemallow accumulated between 3 and 9 times higher concentrations of Pu than creosote and sage brush species. These results support the importance of species specific elemental accumulation strategies rather than exposure duration as the dominant variable influencing Pu concentrations in these plants. Total vegetation elemental concentrations of Ce, Fe, Al, Sm and others were also analyzed. Strong correlations were observed between Fe and Pu. This supports the conclusion that Pu was accumulated as a consequence of the active accumulation of Fe and other plant required nutrients. Cerium and Pu are considered to be chemical analogs. Strong correlations observed in plants support the conclusion that these elements displayed similar geochemical behavior in the environment as it related to the biochemical uptake process of vegetation. Soils were also sampled in association with vegetation samples. This allowed for the calculation of a concentration ratio (CR). The CR values for Pu in plants were highly influenced by the heterogeneity of Pu distribution among sites. Results from the naturally occurring elements of concern were more evenly distributed between sample sites. This allowed for the development of a pattern of plant

  4. Plutonium uptake and behavior in vegetation of the desert southwest: a preliminary assessment.

    PubMed

    Caldwell, Eric; Duff, Martine; Ferguson, Caitlin; Coughlin, Daniel

    2011-09-01

    Eight species of desert vegetation and associated soils were collected from the Nevada National Security Site (N2S2) and analyzed for 238Pu and 239 + 240Pu concentrations. Amongst the plant species sampled were: atmospheric elemental accumulators (moss and lichen), the very slow growing, long-lived creosote bush and the rapidly growing, short-lived cheatgrass brome. The diversity of growth strategies provided insight into the geochemical behavior and bio-availability of Pu at the N2S2. The highest concentrations of Pu were measured in the onion moss (24.27 Bq kg-1 238Pu and 52.78 Bq kg-1 239 + 240Pu) followed by the rimmed navel lichen (8.18 Bq kg-1 and 18.4 Bq kg-1 respectively), pointing to the importance of eolian transport of Pu. Brome and desert globemallow accumulated between 3 and 9 times higher concentrations of Pu than creosote and sage brush species. These results support the importance of species specific elemental accumulation strategies rather than exposure duration as the dominant variable influencing Pu concentrations in these plants. Total vegetation elemental concentrations of Ce, Fe, Al, Sm and others were also analyzed. Strong correlations were observed between Fe and Pu. This supports the conclusion that Pu was accumulated as a consequence of the active accumulation of Fe and other plant required nutrients. Cerium and Pu are considered to be chemical analogs. Strong correlations observed in plants support the conclusion that these elements displayed similar geochemical behavior in the environment as it related to the biochemical uptake process of vegetation. Soils were also sampled in association with vegetation samples. This allowed for the calculation of a concentration ratio (CR). The CR values for Pu in plants were highly influenced by the heterogeneity of Pu distribution among sites. Results from the naturally occurring elements of concern were more evenly distributed between sample sites. This allowed for the development of a pattern of

  5. Plutonium uptake and behavior in vegetation of the desert southwest: a preliminary assessment.

    PubMed

    Caldwell, Eric; Duff, Martine; Ferguson, Caitlin; Coughlin, Daniel

    2011-09-01

    Eight species of desert vegetation and associated soils were collected from the Nevada National Security Site (N2S2) and analyzed for 238Pu and 239 + 240Pu concentrations. Amongst the plant species sampled were: atmospheric elemental accumulators (moss and lichen), the very slow growing, long-lived creosote bush and the rapidly growing, short-lived cheatgrass brome. The diversity of growth strategies provided insight into the geochemical behavior and bio-availability of Pu at the N2S2. The highest concentrations of Pu were measured in the onion moss (24.27 Bq kg-1 238Pu and 52.78 Bq kg-1 239 + 240Pu) followed by the rimmed navel lichen (8.18 Bq kg-1 and 18.4 Bq kg-1 respectively), pointing to the importance of eolian transport of Pu. Brome and desert globemallow accumulated between 3 and 9 times higher concentrations of Pu than creosote and sage brush species. These results support the importance of species specific elemental accumulation strategies rather than exposure duration as the dominant variable influencing Pu concentrations in these plants. Total vegetation elemental concentrations of Ce, Fe, Al, Sm and others were also analyzed. Strong correlations were observed between Fe and Pu. This supports the conclusion that Pu was accumulated as a consequence of the active accumulation of Fe and other plant required nutrients. Cerium and Pu are considered to be chemical analogs. Strong correlations observed in plants support the conclusion that these elements displayed similar geochemical behavior in the environment as it related to the biochemical uptake process of vegetation. Soils were also sampled in association with vegetation samples. This allowed for the calculation of a concentration ratio (CR). The CR values for Pu in plants were highly influenced by the heterogeneity of Pu distribution among sites. Results from the naturally occurring elements of concern were more evenly distributed between sample sites. This allowed for the development of a pattern of

  6. Phylogeography of declining relict and lowland leopard frogs in the desert Southwest of North America

    USGS Publications Warehouse

    Olah-Hemmings, V.; Jaeger, J.R.; Sredl, M.J.; Schlaepfer, Martin A.; Jennings, R.D.; Drost, C.A.; Bradford, D.F.; Riddle, B.R.

    2010-01-01

    We investigated the phylogeography of the closely related relict leopard frog Rana onca (=Lithobates onca) and lowland leopard frog Rana yavapaiensis (=Lithobates yavapaiensis) – two declining anurans from the warm-desert regions of south-western North America. We used sequence data from mitochondrial DNA (mtDNA) to assess 276 individuals representing 30 sites from across current distributions. Our analysis supports a previously determined phylogenetic break between these taxa, and we found no admixing of R. onca and R. yavapaiensis haplotypes within our extensive sampling of sites. Our phylogeographic assessment, however, further divided R. yavapaiensis into two distinct mtDNA lineages, one representing populations across Arizona and northern Mexico and the other a newly discovered population within the western Grand Canyon, Arizona. Estimates of sequence evolution indicate a possible Early Pleistocene divergence of R. onca and R. yavapaiensis, followed by a Middle Pleistocene separation of the western Grand Canyon population of R. yavapaiensis from the main R. yavapaiensis clade. Phylogeographic and demographic analyses indicate population or range expansion for R. yavapaiensis within its core distribution that appears to predate the latest glacial maximum. Species distribution models under current and latest glacial climatic conditions suggest that R. onca and R. yavapaiensis may not have greatly shifted ranges.

  7. Compositions of modern dust and surface sediments in the Desert Southwest, United States

    USGS Publications Warehouse

    Reheis, M.C.; Budahn, J.R.; Lamothe, P.J.; Reynolds, R.L.

    2009-01-01

    Modern dusts across southwestern United States deserts are compositionally similar to dust-rich Av soil horizons (depths of 0-0.5 cm and 1-4 cm at 35 sites) for common crustal elements but distinctly different for some trace elements. Chemical compositions and magnetic properties of the soil samples are similar among sites relative to dust sources, geographic areas, and lithologic substrates. Exceptions are Li, U, and W, enriched in Owens Valley, California, and Mg and Sr, enriched in soils formed on calcareous fan gravel in southeast Nevada. The Av horizons are dominated by dust and reflect limited mixing with substrate sediments. Modern dust samples are also similar across the region, except that Owens Valley dusts are higher in Mg, Ba, and Li and dusts both there and at sites to the north on volcanic substrates are higher in Sb and W. Thus, dust and Av horizons consist of contributions from many different sources that are well mixed before deposition. Modern dusts contain significantly greater amounts of As, Cd, Cr, Cu, Ni, Pb, and Sb than do Av horizons, which record dust additions over hundreds to thousands of years. These results suggest that modern dust compositions are influenced by anthropogenic sources and emissions from Owens (dry) Lake after its artificial desiccation in 1926. Both modern dusts and Av horizons are enriched in As, Ba, Cu, Li, Sb, Th, U, and W relative to average crustal composition, which we interpret to indicate that the geologic sources of dust in the southwestern United States are geochemically distinctive.

  8. Legally White, Socially "Mexican": The Politics of De Jure and De Facto School Segregation in the American Southwest

    ERIC Educational Resources Information Center

    Donato, Ruben; Hanson, Jarrod S.

    2012-01-01

    The history of Mexican American school segregation is complex, often misunderstood, and currently unresolved. The literature suggests that Mexican Americans experienced de facto segregation because it was local custom and never sanctioned at the state level in the American Southwest. However, the same literature suggests that Mexican Americans…

  9. The Prevalence of Metabolic Syndrome and Associated Risk Factors in Northern Plains and Southwest American Indians

    PubMed Central

    Sinclair, Kaìmi A.; Bogart, Andy; Buchwald, Dedra; Henderson, Jeffrey A.

    2011-01-01

    OBJECTIVE To estimate the prevalence of metabolic syndrome by age, sex, and diabetes status in Northern Plains and Southwest American Indians. RESEARCH DESIGN AND METHODS Data for this analysis came from the Education and Research Toward Health (EARTH) study, a 5-year cross-sectional study of Southwest and Northern Plains American Indian adults. The National Cholesterol Education Program's Adult Treatment Panel III (NCEP/ATP III) guidelines were used to identify adults with metabolic syndrome. RESULTS The age-adjusted prevalence of the metabolic syndrome was 49.8% among 4,457 participants aged 18–88 years. Age-adjusted prevalence was 42.4% for participants without diabetes and 86.6% for participants with diabetes. In participants aged <40 years, the overall prevalence of metabolic syndrome was 53.1%; 44.9% after excluding individuals with diabetes. CONCLUSIONS This study confirms a high prevalence of the metabolic syndrome among Northern Plains and Southwest American Indians of all ages. PMID:20864516

  10. PCR primers for microsatellite loci in the desert tortoise (Gopherus agassizii, Testudinidae)

    USGS Publications Warehouse

    Edwards, T.; Goldberg, C.S.; Kaplan, M.E.; Schwalbe, C.R.; Swann, D.E.

    2003-01-01

    The desert tortoise, Gopherus agassizii, is a threatened species native to the North American desert southwest and is recognized as having distinct Mojave and Sonoran populations. We identified six polymorphic microsatellite loci in the desert tortoise. All six loci were polymorphic in Sonoran samples. Five of the loci were variable in Mojave samples with varying degrees of amplification success. Two of the loci exhibited low allelic variation (2-3 alleles) while four were highly variable (8-27 alleles).

  11. Evidence of aqueous secondary organic aerosol formation from biogenic emissions in the North American Sonoran Desert

    PubMed Central

    Youn, Jong-Sang; Wang, Zhen; Wonaschütz, Anna; Arellano, Avelino; Betterton, Eric A.; Sorooshian, Armin

    2013-01-01

    This study examines the role of aqueous secondary organic aerosol formation in the North American Sonoran Desert as a result of intense solar radiation, enhanced moisture, and biogenic volatile organic compounds (BVOCs). The ratio of water-soluble organic carbon (WSOC) to organic carbon (OC) nearly doubles during the monsoon season relative to other seasons of the year. When normalized by mixing height, the WSOC enhancement during monsoon months relative to preceding dry months (May–June) exceeds that of sulfate by nearly a factor of 10. WSOC:OC and WSOC are most strongly correlated with moisture parameters, temperature, and concentrations of O3 and BVOCs. No positive relationship was identified between WSOC or WSOC:OC and anthropogenic tracers such as CO over a full year. This study points at the need for further work to understand the effect of BVOCs and moisture in altering aerosol properties in understudied desert regions. PMID:24115805

  12. Site characterization and performance assessment for a low-level radioactive waste management site in the American Southwest

    SciTech Connect

    Shott, G.J.; Sully, M.J.; Muller, C.J.; Hammermeister, D.P.; Ginanni, J.M.

    1995-11-01

    The Area 5 Radioactive Waste Management Site located in southern Nevada, has been used for the disposal of low-level radioactive waste since 1961. The site is located in the Mohave Desert of the American Southwest, an extremely arid region receiving as little as 0.1 m/yr of precipitation. Site characterization studies have measured the physical, hydrologic, and geochemical properties of core samples collected from 10 shallow boreholes and 3 deep boreholes that extend through the unsaturated zone to the uppermost aquifer. Results indicate that the unsaturated zone consists of 240 m of dry alluvial sediments and is remarkably uniform with respect to most physical parameters. Measurements of saturated hydraulic conductivity with depth showed no evidence of trends, layering, or anisotropy. Parameters for hydraulic functions were not highly variable and exhibited little trend with depth. Water potential profiles indicate that water movement in the upper alluvium is upward, except immediately following a precipitation event. Below the evaporative zone, the liquid flux was downward and of the same order of magnitude as the upward thermal vapor flux induced by the geothermal gradient. The extreme climatic conditions at the site reduce or eliminate many radionuclide release and transport mechanisms. Downward transport of radionuclides to the uppermost aquifer appears unlikely under current climatic conditions. Important radionuclide transport pathways appear to be limited to upward diffusion and advection of gases and biologically-mediated transport. Conceptual models of disposal site performance have been developed based on site characterization studies. The limited transport pathways and limited land use potential of the site provide reasonable assurance that regulatory performance objectives can be met.

  13. Long and spatially variable Neolithic Demographic Transition in the North American Southwest

    PubMed Central

    Kohler, Timothy A.; Reese, Kelsey M.

    2014-01-01

    In many places of the world, a Neolithic Demographic Transition (NDT) is visible as a several-hundred-year period of increased birth rates coupled with stable mortality rates, resulting in dramatic population growth that is eventually curtailed by increased mortality. Similar processes can be reconstructed in particular detail for the North American Southwest, revealing an anomalously long and spatially variable NDT. Irrigation-dependent societies experienced relatively low birth rates but were quick to achieve a high degree of sociopolitical complexity, whereas societies dependent on dry or rainfed farming experienced higher birth rates but less initial sociopolitical complexity. Low birth rates after A.D. 1200 mark the beginning of the decline of the Hohokam. Overall in the Southwest, birth rates increased slowly from 1100 B.C. to A.D. 500, and remained at high levels with some fluctuation until decreasing rapidly beginning A.D. 1300. Life expectancy at 15 increased slowly from 900 B.C. to A.D. 700, and then increased rapidly for 200 y before fluctuating and then declining after A.D. 1400. Life expectancy at birth, on the other hand, generally declined from 1100 B.C. to A.D. 1100/1200, before rebounding. Farmers took two millennia (∼1100 B.C. to ∼A.D. 1000) to reach the carrying capacity of the agricultural niche in the Southwest. PMID:24982134

  14. Sonoran Desert Vegetation Shifts and Watershed-Scale Ecohydrological Dynamics during the North-American Monsoon

    NASA Astrophysics Data System (ADS)

    Pierini, N. A.; Templeton, R. C.; Robles-Morua, A.; Vivoni, E. R.

    2011-12-01

    Semiarid ecosystems are shaped and constrained by water availability. In the Arizona Sonoran desert, rainfall often occurs in short, high intensity summer storms associated with the North American monsoon. Along with natural or anthropogenic disturbances, monsoon conditions have acted to transform these landscapes from desert grassland to woody savannas over the last century. Changes in vegetation properties, structure and patterns in turn impact critical zone water and energy fluxes, including soil moisture and temperature dynamics, evapotranspiration and runoff production. In this study, we present observational and modeling activities conducted in a small watershed located in the Santa Rita Experimental Range, AZ. The desert basin is representative of the landscape vegetation shift and has been characterized by hydrologic and photographic observations over the last 30 years. More recently, we deployed a high-resolution environmental sensor network consisting of 6 rain gauges, 21 soil moisture and temperature profiles, 4 channel runoff flumes and an eddy covariance tower with a complete set of radiation, energy, carbon and water fluxes. In addition, a high-resolution digital terrain model was obtained from LiDAR measurements and a field dGPS survey, allowing characterization of the watershed terrain and plant cover distributions. Using the network, we present preliminary analyses of the temporal and spatial distributions of rainfall, soil moisture and temperature, and channel runoff in the watershed during the summer 2011, as well as land-atmosphere fluxes at the tower location. The field observations are also used for one-dimensional simulations of the TIN-based Real-time Integrated Basin Simulator (tRIBS) designed to explore the influence of the vegetation shifts on the landscape dynamics. Ultimately, applications of the distributed model in the desert basin will allow us to gain insight on the impact of shifting vegetation patterns on the watershed

  15. Abstracts for the October 2012 meeting on Volcanism in the American Southwest, Flagstaff, Arizona

    USGS Publications Warehouse

    Lowenstern, Jacob B.

    2013-01-01

    Though volcanic eruptions are comparatively rare in the American Southwest, the States of Arizona, Colorado, New Mexico, Nevada, and Utah host Holocene volcanic eruption deposits and are vulnerable to future volcanic activity. Compared with other parts of the western United States, comparatively little research has been focused on this area, and eruption probabilities are poorly constrained. Monitoring infrastructure consists of a variety of local seismic networks, and ”backbone“ geodetic networks with little integration. Emergency response planning for volcanic unrest has received little attention by either Federal or State agencies. On October 18–20, 2012, 90 people met at the U.S. Geological Survey campus in Flagstaff, Arizona, providing an opportunity for volcanologists, land managers, and emergency responders to meet, converse, and begin to plan protocols for any future activity. Geologists contributed data on recent findings of eruptive ages, eruption probabilities, and hazards extents (plume heights, ash dispersal). Geophysicists discussed evidence for magma intrusions from seismic, geodetic, and other geophysical techniques. Network operators publicized their recent work and the relevance of their equipment to volcanic regions. Land managers and emergency responders shared their experiences with emergency planning for earthquakes. The meeting was organized out of the recognition that little attention had been paid to planning for or mitigation of volcanic hazards in the American Southwest. Moreover, few geological meetings have hosted a session specifically devoted to this topic. This volume represents one official outcome of the meeting—a collection of abstracts related to talks and poster presentations shared during the first two days of the meeting. In addition, this report includes the meeting agenda as a record of the proceedings. One additional intended outcome will be greater discussion and coordination among emergency responders, geologists

  16. Molecular evidence for Pleistocene glacial cycles driving diversification of a North American desert spider, Agelenopsis aperta.

    PubMed

    Ayoub, Nadia A; Riechert, Susan E

    2004-11-01

    The influence of historical climatic vs. geological changes on species diversification patterns was investigated in a widely distributed North American desert spider, Agelenopsis aperta (Araneae: Agelenidae), with particular reference to Pleistocene glacial cycles and earlier patterns of mountain building. Levels of sequence divergence obtained from the mitochondrial gene, cytochrome oxidase I, dated to the Pleistocene, eliminating Rocky Mountain orogeny as a cause of diversification, as orogeny ended 4 million years ago. The results of phylogenetic and network analyses showed the presence of three geographically defined clades, which were consistent with the presence of at least three glacial refugia: (i) east of the Rocky Mountains; (ii) between the Rocky Mountains and Sierra Nevadas; and (iii) west of the Sierra Nevadas. In addition, populations within the Rocky Mountains exhibited significantly lower genetic diversity than populations east of the Rocky Mountains and the haplotypes found within the Rockies were a subset of eastern haplotypes. These patterns suggest that a post-Pleistocene range expansion occurred out of an eastern glacial refugium into the Rocky Mountains. Examination of phylogeographical studies of other North American desert taxa indicated that mountain building explained diversification patterns more effectively for some taxa but Pleistocene climate change was more important for others, including A. aperta. PMID:15488003

  17. Molecular evidence for Pleistocene glacial cycles driving diversification of a North American desert spider, Agelenopsis aperta.

    PubMed

    Ayoub, Nadia A; Riechert, Susan E

    2004-11-01

    The influence of historical climatic vs. geological changes on species diversification patterns was investigated in a widely distributed North American desert spider, Agelenopsis aperta (Araneae: Agelenidae), with particular reference to Pleistocene glacial cycles and earlier patterns of mountain building. Levels of sequence divergence obtained from the mitochondrial gene, cytochrome oxidase I, dated to the Pleistocene, eliminating Rocky Mountain orogeny as a cause of diversification, as orogeny ended 4 million years ago. The results of phylogenetic and network analyses showed the presence of three geographically defined clades, which were consistent with the presence of at least three glacial refugia: (i) east of the Rocky Mountains; (ii) between the Rocky Mountains and Sierra Nevadas; and (iii) west of the Sierra Nevadas. In addition, populations within the Rocky Mountains exhibited significantly lower genetic diversity than populations east of the Rocky Mountains and the haplotypes found within the Rockies were a subset of eastern haplotypes. These patterns suggest that a post-Pleistocene range expansion occurred out of an eastern glacial refugium into the Rocky Mountains. Examination of phylogeographical studies of other North American desert taxa indicated that mountain building explained diversification patterns more effectively for some taxa but Pleistocene climate change was more important for others, including A. aperta.

  18. Ecological niche modeling of Coccidioides spp. in western North American deserts.

    PubMed

    Baptista-Rosas, Raúl C; Hinojosa, Alejandro; Riquelme, Meritxell

    2007-09-01

    Coccidioidomycosis is an endemic infectious disease in western North American deserts caused by the dimorphic ascomycete Coccidioides spp. Even though there has been an increase in the number of reported cases in the last years, few positive isolations have been obtained from soil samples in endemic areas for the disease. This low correlation between epidemiological and environmental data prompted us to better characterize the fundamental ecological niche of this important fungal pathogen. By using a combination of environmental variables and geospatially referenced points, where positive isolations had been obtained in southern California and Arizona (USA) and Sonora (Mexico), we have applied Genetic Algorithm for Rule Set Production (GARP) and Geographical Information Systems (GIS) to characterize the most likely ecological conditions favorable for the presence of the fungus. This model, based on environmental variables, allowed us to identify hotspots for the presence of the fungus in areas of southern California, Arizona, Texas, Baja California, and northern Mexico, whereas an alternative model based on bioclimatic variables gave us much broader probable distribution areas. We have overlapped the hotspots obtained with the environmental model with the available epidemiological information and have found a high match. Our model suggests that the most probable fundamental ecological niche for Coccidioides spp. is found in the arid lands of the North American deserts and provides the methodological basis to further characterize the realized ecological niche of Coccidioides spp., which would ultimately contribute to design smart field-sampling strategies.

  19. The Historic 2011 American Southwest Fire Season: More than a Lack of Precipitation

    NASA Astrophysics Data System (ADS)

    Rahn, T.; Hryniw, N.; Trugman, A. T.

    2011-12-01

    The 2011 fire season in the American Southwest has been historical by almost any measure. Six of the ten largest fires in TX occurred in the month of April and over 16,000 fires requiring response have resulted in 1.4 million hectares burned since the beginning of the fire season on 15 Nov., 2010. The Wallow Fire and the Horseshoe 2 Fire, both beginning in May in AZ became the state's first and fourth largest fires in history and consumed 217,000+ ha and 90,000 ha respectively. The Las Conchas fire in June near Los Alamos NM burned over 17,000 ha in its first 18 hours and ultimately became the largest single fire in NM state history at 63,000+ ha. The extent of these fires is no doubt related to ongoing regional drought associated with the moderate 2010-2011 La Niña conditions. Given the extent and severity of the Southwest 2011 fire year, even when compared to other recent drought years, we speculated that there may be other factors in addition to lack of precipitation influencing their development. We compiled 26 years of meteorological data from 138 stations in TX, AZ, NM as well as adjoining states and Mexico to investigate the potential influence of temperature, humidity and wind on fire development. We show that dew point suppression, even when referenced to other significant drought years, was widespread across West TX, through NM and the eastern half of AZ, with an anomaly averaging ~10 degrees below normal. In addition, above normal sustained winds were observed in Northern NM and Eastern AZ and may have played a factor in the rapid growth of fires in those localities. A broad temperature anomaly centered over North TX and Southwest OK and extending westward over NM was also observed.

  20. Toward linking maize chemistry to archaeological agricultural sites in the North American Southwest

    USGS Publications Warehouse

    Cordell, L.S.; Durand, S.R.; Antweiler, R.C.; Taylor, H.E.

    2001-01-01

    Maize (Zea mays L.) was the staple domestic food crop for Ancestral Pueblo people throughout the northern American Southwest. It is thought to have been the basic food of the inhabitants of Chaco Canyon. New Mexico, a location that was a major centre of Ancestral Pueblo building and population during the 11th and early 12th centuries AD. Modern heirloom varieties of Native American corn have been difficult to grow in experimental fields in Chaco Canyon. Given an abundance of apparent storage structures in Chacoan buildings, it is possible that some corn recovered from archaeological contexts, was imported from surrounding areas. The ultimate goal of this research is to determine whether the corn in Chaco Canyon was grown locally or imported. This paper establishes the feasibility of a method to accomplish this goal. This study reports the results of using inductively coupled plasma-mass spectrometric (ICP-MS) instrumentation to determine chemical constituents of experimental fields and modern heirloom varieties of Native American corn. Analysis of 19 elements is adequate to differentiate soil and corn from three field areas. These results are promising: however, a number of problems, including post-depositional alterations in maize, remain to be solved. ?? 2001 Academic Press.

  1. PREFERRED DRUG RESISTANCE STRATEGIES OF URBAN AMERICAN INDIAN YOUTH OF THE SOUTHWEST*

    PubMed Central

    KULIS, STEPHEN; BROWN, EDDIE F.

    2011-01-01

    This study explored the drug resistance strategies that urban American Indian adolescents consider the best and worst ways to respond to offers of alcohol, cigarettes, and marijuana. Focus group data were collected from 11 female and 9 male American Indian adolescents attending urban middle schools in the southwest. The youth were presented with hypothetical substance offer scenarios and alternative ways of responding, based on real-life narratives of similar youth. They were asked to choose a preferred strategy, one that would work every time, and a rejected strategy, one they would never use. Using eco-developmental theory, patterns in the preferred and rejected strategies were analyzed to identify culturally specific and socially competent ways of resisting substance offers. The youth preferred strategies that included passive, non-verbal strategies like pretending to use the substance, as well as assertive strategies like destroying the substance. The strategies they rejected were mostly socially non-competent ones like accepting the substance or responding angrily. Patterns of preferred and rejected strategies varied depending on whether the offer came from a family member or non-relative. These patterns have suggestive implications for designing more effective prevention programs for the growing yet under-served urban American Indian youth population. PMID:21888001

  2. THE ECOLOGICAL AND HYDROLOGICAL SIGNIFICANCE OF EPHEMERAL AND INTERMITTENT STREAMS IN THE ARID AND SEMI-ARID AMERICAN SOUTHWEST

    EPA Science Inventory

    This report represents a state-of-the-art synthesis of current knowledge of the ecology and hydrology of ephemeral (dry washes) and intermittent streams in the American Southwest, and may have important bearing on establishing nexus to traditional navigable waters (TNW) and defin...

  3. The Many Roles of the ABCA Member; Proceedings of the 1975 Southwest American Business Communication Association Spring Conference.

    ERIC Educational Resources Information Center

    Bruno, Sam J., Ed.

    The written proceedings of the 1975 Southwest American Business Communication Association (ABCA) Spring Conference, in Houston, Texas, whose theme was "The Many Roles of the ABCA Member" are contained in this report. The five major parts of the document discuss the ABCA member as a job counselor, graduate research advisor, semanticist, and…

  4. Hierarchy and social inequality in the American Southwest, A.D. 800-1200.

    PubMed

    Plog, Stephen; Heitman, Carrie

    2010-11-16

    Chaco Canyon in northwestern New Mexico has been the focus of much recent archaeological research on Pueblo groups who lived during the 9th through 12th centuries in the American Southwest. Here, we examine variation in mortuary patterns in the canyon, focusing in particular on one mortuary crypt, to address questions of social differentiation and the chronology of important sociopolitical processes. Based on new radiocarbon dates as well as reanalysis of the stratigraphy and spatial distribution of materials in the mortuary crypt, we conclude that significant social differentiation began in Chaco ca. 150-200 y earlier than suggested by previous research. We argue that social inequality was sanctified and legitimized by linking people to founders, ancestors, and cosmological forces.

  5. The challenge of accurately quantifying future megadrought risk in the American Southwest

    NASA Astrophysics Data System (ADS)

    Coats, Sloan; Mankin, Justin S.

    2016-09-01

    American Southwest (ASW) megadroughts represent decadal-scale periods of dry conditions the near-term risks of which arise from natural low-frequency hydroclimate variability and anthropogenic forcing. A large single-climate-model ensemble indicates that anthropogenic forcing increases near-term ASW megadrought risk by a factor of 100; however, accurate risk assessment remains a challenge. At the global-scale we find that anthropogenic forcing may alter the variability driving megadroughts over 55% of land areas, undermining accurate assessments of their risk. For the remaining areas, current ensembles are too small to characterize megadroughts' driving variability. For example, constraining uncertainty in near-term ASW megadrought risk to 5 percentage points with high confidence requires 287 simulations. Such ensemble sizes are beyond current computational and storage resources, and these limitations suggest that constraining errors in near-term megadrought risk projections with high confidence—even in places where underlying variability is stationary—is not currently possible.

  6. Hierarchy and social inequality in the American Southwest, A.D. 800–1200

    PubMed Central

    Plog, Stephen; Heitman, Carrie

    2010-01-01

    Chaco Canyon in northwestern New Mexico has been the focus of much recent archaeological research on Pueblo groups who lived during the 9th through 12th centuries in the American Southwest. Here, we examine variation in mortuary patterns in the canyon, focusing in particular on one mortuary crypt, to address questions of social differentiation and the chronology of important sociopolitical processes. Based on new radiocarbon dates as well as reanalysis of the stratigraphy and spatial distribution of materials in the mortuary crypt, we conclude that significant social differentiation began in Chaco ca. 150–200 y earlier than suggested by previous research. We argue that social inequality was sanctified and legitimized by linking people to founders, ancestors, and cosmological forces. PMID:21059921

  7. Phylogenetic community structure of North American desert bats: influence of environment at multiple spatial and taxonomic scales.

    PubMed

    Patrick, Lorelei E; Stevens, Richard D

    2016-07-01

    Numerous processes influence community structure. The relative importance of these processes is thought to vary with spatial, temporal and taxonomic scales: density-dependent interactions are thought to be most important at small scales; at intermediate scales, environmental conditions may be the most influential factor; and biogeographic processes are thought to be of greater importance at larger scales. Additionally, the stress-dominance hypothesis suggests that communities experiencing harsher environmental conditions will be predominantly structured by habitat filtering, whereas communities experiencing more favourable conditions will be structured predominantly by density-dependent interactions such as competition. The aim of this study was to investigate the influence of environmental factors on phylogenetic community structure (PCS) of North American desert bats at multiple spatial and taxonomic scales. We also examined whether the stress-dominance hypothesis is upheld in desert bats across an environmental gradient. Phylogenetic community structure metrics were calculated using species pools that differed in spatial (from all deserts to individual deserts) and taxonomic (all bat taxa, a single family and a single genus) scales. We calculated mean temperature, precipitation and seasonality for each site to determine whether environmental gradients were related to degree of community structure. At the largest spatial and taxonomic scales, communities were significantly phylogenetically clustered while degree of clustering decreased at the smallest spatial and taxonomic scales. Climatic data, particularly mean temperature and temperature seasonality, were important predictors of PCS at larger scales and under harsher conditions, but at smaller scales and in less stressful conditions there was a weaker relationship between PCS and climate. This suggests that North American deserts, while harsh, are not uniform in the challenges they present to the faunas

  8. Projected vegetation changes for the American Southwest: combined dynamic modeling and bioclimatic-envelope approach.

    PubMed

    Notaro, Michael; Mauss, Adrien; Williams, John W

    2012-06-01

    This study focuses on potential impacts of 21st century climate change on vegetation in the Southwest United States, based on debiased and interpolated climate projections from 17 global climate models used in the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Among these models a warming trend is universal, but projected changes in precipitation vary in sign and magnitude. Two independent methods are applied: a dynamic global vegetation model to assess changes in plant functional types and bioclimatic envelope modeling to assess changes in individual tree and shrub species and biodiversity. The former approach investigates broad responses of plant functional types to climate change, while considering competition, disturbances, and carbon fertilization, while the latter approach focuses on the response of individual plant species, and net biodiversity, to climate change. The dynamic model simulates a region-wide reduction in vegetation cover during the 21st century, with a partial replacement of evergreen trees with grasses in the mountains of Colorado and Utah, except at the highest elevations, where tree cover increases. Across southern Arizona, central New Mexico, and eastern Colorado, grass cover declines, in some cases abruptly. Due to the prevalent warming trend among all 17 climate models, vegetation cover declines in the 21st century, with the greatest vegetation losses associated with models that project a drying trend. The inclusion of the carbon fertilization effect largely ameliorates the projected vegetation loss. Based on bioclimatic envelope modeling for the 21st century, the number of tree and shrub species that are expected to experience robust declines in range likely outweighs the number of species that are expected to expand in range. Dramatic shifts in plant species richness are projected, with declines in the high-elevation evergreen forests, increases in the eastern New Mexico prairies, and a northward shift of the

  9. Projected vegetation changes for the American Southwest: combined dynamic modeling and bioclimatic-envelope approach.

    PubMed

    Notaro, Michael; Mauss, Adrien; Williams, John W

    2012-06-01

    This study focuses on potential impacts of 21st century climate change on vegetation in the Southwest United States, based on debiased and interpolated climate projections from 17 global climate models used in the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Among these models a warming trend is universal, but projected changes in precipitation vary in sign and magnitude. Two independent methods are applied: a dynamic global vegetation model to assess changes in plant functional types and bioclimatic envelope modeling to assess changes in individual tree and shrub species and biodiversity. The former approach investigates broad responses of plant functional types to climate change, while considering competition, disturbances, and carbon fertilization, while the latter approach focuses on the response of individual plant species, and net biodiversity, to climate change. The dynamic model simulates a region-wide reduction in vegetation cover during the 21st century, with a partial replacement of evergreen trees with grasses in the mountains of Colorado and Utah, except at the highest elevations, where tree cover increases. Across southern Arizona, central New Mexico, and eastern Colorado, grass cover declines, in some cases abruptly. Due to the prevalent warming trend among all 17 climate models, vegetation cover declines in the 21st century, with the greatest vegetation losses associated with models that project a drying trend. The inclusion of the carbon fertilization effect largely ameliorates the projected vegetation loss. Based on bioclimatic envelope modeling for the 21st century, the number of tree and shrub species that are expected to experience robust declines in range likely outweighs the number of species that are expected to expand in range. Dramatic shifts in plant species richness are projected, with declines in the high-elevation evergreen forests, increases in the eastern New Mexico prairies, and a northward shift of the

  10. Native American depopulation, reforestation, and fire regimes in the Southwest United States, 1492-1900 CE.

    PubMed

    Liebmann, Matthew J; Farella, Joshua; Roos, Christopher I; Stack, Adam; Martini, Sarah; Swetnam, Thomas W

    2016-02-01

    Native American populations declined between 1492 and 1900 CE, instigated by the European colonization of the Americas. However, the magnitude, tempo, and ecological effects of this depopulation remain the source of enduring debates. Recently, scholars have linked indigenous demographic decline, Neotropical reforestation, and shifting fire regimes to global changes in climate, atmosphere, and the Early Anthropocene hypothesis. In light of these studies, we assess these processes in conifer-dominated forests of the Southwest United States. We compare light detection and ranging data, archaeology, dendrochronology, and historical records from the Jemez Province of New Mexico to quantify population losses, establish dates of depopulation events, and determine the extent and timing of forest regrowth and fire regimes between 1492 and 1900. We present a new formula for the estimation of Pueblo population based on architectural remains and apply this formula to 18 archaeological sites in the Jemez Province. A dendrochronological study of remnant wood establishes dates of terminal occupation at these sites. By combining our results with historical records, we report a model of pre- and post-Columbian population dynamics in the Jemez Province. Our results indicate that the indigenous population of the Jemez Province declined by 87% following European colonization but that this reduction occurred nearly a century after initial contact. Depopulation also triggered an increase in the frequency of extensive surface fires between 1640 and 1900. Ultimately, this study illustrates the quality of integrated archaeological and paleoecological data needed to assess the links between Native American population decline and ecological change after European contact.

  11. An Ecohydrological Approach to Riparian Restoration Planning in the American Southwest

    NASA Astrophysics Data System (ADS)

    Leverich, G. T.; Orr, B.; Diggory, Z.; Dudley, T.; Hatten, J.; Hultine, K. R.; Johnson, M. P.; Orr, D.

    2014-12-01

    Riparian systems across the American southwest region are under threat from a growing and intertwined cast of natural and anthropogenic stressors, including flooding, drought, invasion by non-native plants, wildfire, urban encroachment, and land- and water-use practices. In relatively remote and unregulated systems like the upper Gila River in Arizona, riparian habitat value has persisted reasonably well despite much of it being densely infested with non-native tamarisk (salt cedar). A new concern in the watershed, however, is the eventual arrival of the tamarisk leaf beetle that is expected to soon colonize the tamarisk-infested riparian corridor as the beetle continues to spread across the southwest region. While there are numerous potential benefits to tamarisk suppression (e.g., groundwater conservation, riparian habitat recovery, fire-risk reduction), short-term negative consequences are also possible, such as altered channel hydraulics and canopy defoliation during bird nesting season (e.g., the endangered southwestern willow flycatcher). In preparation for anticipated impacts following beetle colonization, we developed a holistic restoration framework to promote recovery of native riparian habitat and subsequent local increases in avian population. Pivotal to this process was an ecohydrological assessment that identified sustainable restoration sites based on consideration of natural and anthropogenic factors that, together, influence restoration opportunities—flood-scour dynamics, vegetation community structure and resilience, surface- and groundwater availability, soil texture and salinity, wildfire potential, and land-use activities. Data collected included high-resolution remote-sensing products, GIS-based delineation of geomorphic activity, and vegetation field mapping. These data along with other information generated, including pre-biocontrol vegetation monitoring and flycatcher-habitat modeling, were synthesized to produce a comprehensive

  12. Severe mortality of a population of threatened Agassiz’s desert tortoises: the American badger as a potential predator

    USGS Publications Warehouse

    Emblidge, Patrick G.; Nussear, Ken E.; Esque, Todd C.; Aiello, Christina M.; Walde, Andrew D.

    2015-01-01

    In the Mojave Desert of the southwestern United States, adult Agassiz’s desert tortoises Gopherus agassizii typically experience high survival, but population declines associated with anthropogenic impacts led to their listing as a threatened Species under the US Endangered Species Act in 1990. Predation of adult tortoises is not often considered a significant threat as they are adapted to deter most predation attempts. Despite these adaptations, some populations have experienced elevated mortality attributed to predators, suggesting that predation pressure may occasionally increase. During the tortoise activity seasons of 2012 and 2013, we observed unsustainably high mortality in 1 of 4 populations of adult desert tortoises (22 and 84%, respectively) in the western Mojave Desert in the vicinity of Barstow, CA. Photographic evidence from trail cameras and examination of carcass condition suggest that American badgers Taxidea taxus— a sometimes cited but unconfirmed predator of adult tortoises — may have been responsible for some of the mortality observed. We discuss the American badger as a plausible predator of a local tortoise population, but recommend further investigation into these events and the impacts such mortality can have on tortoise persistence.

  13. Selection and Characterization of Terrestrial Analogs to the Martian Crust: Field Sites in the U.S. Desert Southwest for Testing Radar Sounders

    NASA Astrophysics Data System (ADS)

    Dinwiddie, C. L.; Stamatakos, J. A.; Gonzalez, S. H.; Grimm, R. E.; McKague, H. L.; Browning, L. B.; Ferrill, D. A.

    2004-05-01

    Ideal terrestrial analogues to Mars combine features such as an arid environment, cold climate, a relatively deep water table, saline pore waters, and bedrock dominated by basalt (although more acidic volcanic strata may also be acceptable). The growing evidence for extensive eolian and fluvial sedimentary deposits on Mars demonstrates that investigation of terrestrial analogues for these environments is also needed. Because of large crustal magnetic anomalies in the southern hemisphere of Mars, highly magnetic terrestrial analogues may also be important, especially for some geophysical applications. Terrestrial analogues best suited for calibrating a suite of geophysical instruments, especially radar sounders, need to be sufficiently characterized to provide an accurate understanding of the local geologic context. During site selection, preference should be given to sites that possess a range of physical properties, stratigraphic complexity, and environmental conditions anticipated for Mars. Accessibility, local infrastructure, and cost (travel expenses, etc.) are also important site selection considerations. A number of favorable analogue sites with locations in the U.S. Desert Southwest were recommended in the 2001 National Research Council Decadal Study report on Terrestrial Analogues to Mars as potentially offering a substantial amount of scientific and technical return. Many of these analogues, however, lack sufficient characterization for prompt testing and calibration of Martian radar sounding devices. In this study, we explore new analogue sites, including sites where extensive geological, geophysical, geochemical, hydrogeological, and climate data already exist. While not cold, these sites are relatively arid with deep water tables and offer complex stratigraphy, including highly magnetic basalts, pyroclastic ashflow tuffs, and alluvium. To support current (i.e., MARSIS) and future subsurface radar-sounding missions to Mars planned for the next decade, we

  14. Native American depopulation, reforestation, and fire regimes in the Southwest United States, 1492-1900 CE.

    PubMed

    Liebmann, Matthew J; Farella, Joshua; Roos, Christopher I; Stack, Adam; Martini, Sarah; Swetnam, Thomas W

    2016-02-01

    Native American populations declined between 1492 and 1900 CE, instigated by the European colonization of the Americas. However, the magnitude, tempo, and ecological effects of this depopulation remain the source of enduring debates. Recently, scholars have linked indigenous demographic decline, Neotropical reforestation, and shifting fire regimes to global changes in climate, atmosphere, and the Early Anthropocene hypothesis. In light of these studies, we assess these processes in conifer-dominated forests of the Southwest United States. We compare light detection and ranging data, archaeology, dendrochronology, and historical records from the Jemez Province of New Mexico to quantify population losses, establish dates of depopulation events, and determine the extent and timing of forest regrowth and fire regimes between 1492 and 1900. We present a new formula for the estimation of Pueblo population based on architectural remains and apply this formula to 18 archaeological sites in the Jemez Province. A dendrochronological study of remnant wood establishes dates of terminal occupation at these sites. By combining our results with historical records, we report a model of pre- and post-Columbian population dynamics in the Jemez Province. Our results indicate that the indigenous population of the Jemez Province declined by 87% following European colonization but that this reduction occurred nearly a century after initial contact. Depopulation also triggered an increase in the frequency of extensive surface fires between 1640 and 1900. Ultimately, this study illustrates the quality of integrated archaeological and paleoecological data needed to assess the links between Native American population decline and ecological change after European contact. PMID:26811459

  15. Native American depopulation, reforestation, and fire regimes in the Southwest United States, 1492–1900 CE

    PubMed Central

    Liebmann, Matthew J.; Farella, Joshua; Roos, Christopher I.; Stack, Adam; Martini, Sarah

    2016-01-01

    Native American populations declined between 1492 and 1900 CE, instigated by the European colonization of the Americas. However, the magnitude, tempo, and ecological effects of this depopulation remain the source of enduring debates. Recently, scholars have linked indigenous demographic decline, Neotropical reforestation, and shifting fire regimes to global changes in climate, atmosphere, and the Early Anthropocene hypothesis. In light of these studies, we assess these processes in conifer-dominated forests of the Southwest United States. We compare light detection and ranging data, archaeology, dendrochronology, and historical records from the Jemez Province of New Mexico to quantify population losses, establish dates of depopulation events, and determine the extent and timing of forest regrowth and fire regimes between 1492 and 1900. We present a new formula for the estimation of Pueblo population based on architectural remains and apply this formula to 18 archaeological sites in the Jemez Province. A dendrochronological study of remnant wood establishes dates of terminal occupation at these sites. By combining our results with historical records, we report a model of pre- and post-Columbian population dynamics in the Jemez Province. Our results indicate that the indigenous population of the Jemez Province declined by 87% following European colonization but that this reduction occurred nearly a century after initial contact. Depopulation also triggered an increase in the frequency of extensive surface fires between 1640 and 1900. Ultimately, this study illustrates the quality of integrated archaeological and paleoecological data needed to assess the links between Native American population decline and ecological change after European contact. PMID:26811459

  16. Vulnerability and adaptation to severe weather events in the American southwest

    SciTech Connect

    Boero, Riccardo; Bianchini, Laura; Pasqualini, Donatella

    2015-05-04

    Climate change can induce changes in the frequency of severe weather events representing a threat to socio-economic development. It is thus of uttermost importance to understand how the vulnerability to the weather of local communities is determined and how adaptation public policies can be effectively put in place. We focused our empirical analysis on the American Southwest. Results show that, consistently with the predictions of an investment model, economic characteristics signaling local economic growth in the near future decrease the level of vulnerability. We also show that federal governments transfers and grants neither work to support recovery from and adaptation to weather events nor to distribute their costs over a broader tax base. Finally, we show that communities relying on municipal bonds to finance adaptation and recovery policies can benefit from local acknowledgment of the need for such policies and that they do not have to pay lenders a premium for the risk induced by weather events. In conclusion, our findings suggest that determinants of economic growth support lower vulnerability to the weather and increase options for financing adaptation and recovery policies, but also that only some communities are likely to benefit from those processes.

  17. Carbon and nutrient cycling in ephemeral streams in the American Southwest

    NASA Astrophysics Data System (ADS)

    Lohse, K. A.; Meixner, T.

    2012-12-01

    Ephemeral streams are an important but little studied resource in the American Southwest. Ephemeral streams receive a subsidy of organic matter and nutrients in addition to water from their surrounding upland ecosystems. Given the hydrologic variability and additional water present in ephemeral stream systems, the upland subsidy to these systems might either lead to elevated organic matter and nutrient concentrations or more rapid processing and thus lower organic matter and nutrient states than surrounding uplands. Here we examine how carbon and nutrient pools and process rates vary across a range of ephemeral, intermittent to perennial streams in Arizona. We compare soil pools and process rates in the ephemeral wash relative to riparian and upland position along three lateral transects at each of the stream reaches (n=13 sites) prior to and post-monsoon rains. We also compared rates of litter decomposition at all sites with two types of litter, oak and sycamore. Nitrogen pools and process rates varied with position and season. Phosphorus availability was high across sites and relatively invariable. Resin exchange bags showed high availability of ammonium, nitrate, and phosphorus with the onset of the monsoon season. Rates of decomposition were higher in washes than riparian and upland positions and slower for oak compared to sycamore leaves. Eighty-six of the oak compared to seventy four percent of the sycamore mass was remaining after 180 days. Our findings suggest that upland subsidies lead to more rapid processing and lower organic matter in washes than surrounding uplands.

  18. Vulnerability and adaptation to severe weather events in the American southwest

    DOE PAGESBeta

    Boero, Riccardo; Bianchini, Laura; Pasqualini, Donatella

    2015-05-04

    Climate change can induce changes in the frequency of severe weather events representing a threat to socio-economic development. It is thus of uttermost importance to understand how the vulnerability to the weather of local communities is determined and how adaptation public policies can be effectively put in place. We focused our empirical analysis on the American Southwest. Results show that, consistently with the predictions of an investment model, economic characteristics signaling local economic growth in the near future decrease the level of vulnerability. We also show that federal governments transfers and grants neither work to support recovery from and adaptationmore » to weather events nor to distribute their costs over a broader tax base. Finally, we show that communities relying on municipal bonds to finance adaptation and recovery policies can benefit from local acknowledgment of the need for such policies and that they do not have to pay lenders a premium for the risk induced by weather events. In conclusion, our findings suggest that determinants of economic growth support lower vulnerability to the weather and increase options for financing adaptation and recovery policies, but also that only some communities are likely to benefit from those processes.« less

  19. Relative Impacts of Mitigation, Temperature, and Precipitation on 21st-Century Megadrought Risk in the American Southwest

    NASA Technical Reports Server (NTRS)

    Ault, Toby R.; Mankin, Justin S.; Cook, Benjamin I.; Smerdon, Jason E.

    2015-01-01

    Megadroughts are comparable in severity to the worst droughts of the 20th century but are of much longer duration. A megadrought in the American Southwest would impose unprecedented stress on the limited water resources of the area, making it critical to evaluate future risks not only under different climate change mitigation scenarios but also for different aspects of regional hydroclimate. We find that changes in the mean hydroclimate state, rather than its variability, determine megadrought risk in the American Southwest. Estimates of megadrought probabilities based on precipitation alone tend to underestimate risk. Furthermore, business-as-usual emissions of greenhouse gases will drive regional warming and drying, regardless of large precipitation uncertainties. We find that regional temperature increases alone push megadrought risk above 70, 90, or 99% by the end of the century, even if precipitation increases moderately, does not change, or decreases, respectively. Although each possibility is supported by some climate model simulations, the latter is the most common outcome for the American Southwest in Coupled Model Intercomparison 5 generation models. An aggressive reduction in global greenhouse gas emissions cuts megadrought risks nearly in half.

  20. Relative impacts of mitigation, temperature, and precipitation on 21st-century megadrought risk in the American Southwest

    PubMed Central

    Ault, Toby R.; Mankin, Justin S.; Cook, Benjamin I.; Smerdon, Jason E.

    2016-01-01

    Megadroughts are comparable in severity to the worst droughts of the 20th century but are of much longer duration. A megadrought in the American Southwest would impose unprecedented stress on the limited water resources of the area, making it critical to evaluate future risks not only under different climate change mitigation scenarios but also for different aspects of regional hydroclimate. We find that changes in the mean hydroclimate state, rather than its variability, determine megadrought risk in the American Southwest. Estimates of megadrought probabilities based on precipitation alone tend to underestimate risk. Furthermore, business-as-usual emissions of greenhouse gases will drive regional warming and drying, regardless of large precipitation uncertainties. We find that regional temperature increases alone push megadrought risk above 70, 90, or 99% by the end of the century, even if precipitation increases moderately, does not change, or decreases, respectively. Although each possibility is supported by some climate model simulations, the latter is the most common outcome for the American Southwest in Coupled Model Intercomparison 5 generation models. An aggressive reduction in global greenhouse gas emissions cuts megadrought risks nearly in half. PMID:27713927

  1. Atherosclerosis and atherosensitivity in two southwest Algerian desert rodents, Psammomys obesus and Gerbillus gerbillus, and in Rattus norvegicus

    PubMed Central

    El-Aoufi, Salima; Lazourgui, Mohamed-Amine; Griene, Lakhdar; Maouche, Boubekeur

    2012-01-01

    Cardiovascular disease, including atherosclerosis, is the leading cause of death in patients with diabetes worldwide; thus, it is a major medical concern. The endothelium contributes to the control of many vascular functions, and clinical observations show that it is a primary target for diabetic syndrome. To get better insight into the mechanisms underlying atherosclerosis, we studied the interspecific differences in the arterial metabolisms of two, Psammomys obesus and Gerbillus gerbillus, as well as Rattus norvegicus (Wistar rat), well known for its atheroresistance. Twenty-two enzymatic activities and six macromolecular substances were histochemically compared in the two desert species and in Wistar aortas (abdominal and thoracic) and arteries (femoral and caudal) embedded in a common block. In the healthy adult rodents, enzyme activities were very intense. They demonstrated that aortic myocytes are capable of various synthesis and catabolism processes. However, considering the frequency of atherosclerosis and its phenotypes, significant differences appeared between the species studied. Our comparative study shows that aortic atherosensitive animals have several common metabolic characteristics, which are found in Psammomys rich in metachromatic glycosaminoglycans (involved in the inhibition of lipolysis and in calcification of the organic matrix), reduced activity in enzymes related to the Krebs cycle (weakening energetic power), and low lipolytic enzyme, adenosine triphosphatase, and adenosine diphosphatase activities. However, the most fundamental pathophysiological difference is the low lipolytic power of the aorta of Psammomys when compared to Wistar rats. This characteristic determines its atherosensitivity and makes this animal model more applicable to the experimental development of atherosclerosis. PMID:23055758

  2. Multiple Pleistocene refugia and Holocene range expansion of an abundant southwestern American desert plant species (Melampodium leucanthum, Asteraceae).

    PubMed

    Rebernig, Carolin A; Schneeweiss, Gerald M; Bardy, Katharina E; Schönswetter, Peter; Villaseñor, Jose L; Obermayer, Renate; Stuessy, Tod F; Weiss-Schneeweiss, Hanna

    2010-08-01

    Pleistocene climatic fluctuations had major impacts on desert biota in southwestern North America. During cooler and wetter periods, drought-adapted species were isolated into refugia, in contrast to expansion of their ranges during the massive aridification in the Holocene. Here, we use Melampodium leucanthum (Asteraceae), a species of the North American desert and semi-desert regions, to investigate the impact of major aridification in southwestern North America on phylogeography and evolution in a widespread and abundant drought-adapted plant species. The evidence for three separate Pleistocene refugia at different time levels suggests that this species responded to the Quaternary climatic oscillations in a cyclic manner. In the Holocene, once differentiated lineages came into secondary contact and intermixed, but these range expansions did not follow the eastwardly progressing aridification, but instead occurred independently out of separate Pleistocene refugia. As found in other desert biota, the Continental Divide has acted as a major migration barrier for M. leucanthum since the Pleistocene. Despite being geographically restricted to the eastern part of the species' distribution, autotetraploids in M. leucanthum originated multiple times and do not form a genetically cohesive group. PMID:20670366

  3. Grief and burial in the American Southwest: the role of evolutionary theory in the interpretation of mortuary remains.

    PubMed

    MacDonald, D H

    2001-10-01

    Evolutionary theory, in consort with Marxism and processualism, provides new insights into the interpretation of grave-good variation. Processual interpretations of burial sites in the American Southwest cite age, sex, or social rank as the main determinants of burial-good variation. Marxist theorists suggest that mortuary ritual mediates social tension between an egalitarian mindset and an existing social inequality. Evolutionary theory provides a supplementary explanatory framework. Recent studies guided by kin-selection theory suggest that humans grieve more for individuals of high reproductive value and genetic relatedness. Ethnographic examples also show that individuals mourn more intensively and, thus, place more social emphasis on burials of individuals of highest reproductive value (young adults). Analysis of grave goods from La Ciudad, a Hohokam site in the American Southwest, supports the hypothesis that labor value, reproductive value, and grief contributed to grave-good differentiation. At La Ciudad, individuals between the ages of 10 and 20 possessed more and higher-quality grave goods on average than any other age group. Grief at the loss of a young adult of high reproductive and labor value may facilitate explanation of mortuary variation at La Ciudad, as well as other sites in the greater Southwest and beyond. PMID:20043376

  4. Economic performance of irrigation capacity development to adapt to climate in the American Southwest

    NASA Astrophysics Data System (ADS)

    Ward, Frank A.; Crawford, Terry L.

    2016-09-01

    Growing demands for food security to feed increasing populations worldwide have intensified the search for improved performance of irrigation, the world's largest water user. These challenges are raised in the face of climate variability and from growing environmental demands. Adaptation measures in irrigated agriculture include fallowing land, shifting cropping patterns, increased groundwater pumping, reservoir storage capacity expansion, and increased production of risk-averse crops. Water users in the Gila Basin headwaters of the U.S. Lower Colorado Basin have faced a long history of high water supply fluctuations producing low-valued defensive cropping patterns. To date, little research grade analysis has investigated economically viable measures for irrigation development to adjust to variable climate. This gap has made it hard to inform water resource policy decisions on workable measures to adapt to climate in the world's dry rural areas. This paper's contribution is to illustrate, formulate, develop, and apply a new methodology to examine the economic performance from irrigation capacity improvements in the Gila Basin of the American Southwest. An integrated empirical optimization model using mathematical programming is developed to forecast cropping patterns and farm income under two scenarios (1) status quo without added storage capacity and (2) with added storage capacity in which existing barriers to development of higher valued crops are dissolved. We find that storage capacity development can lead to a higher valued portfolio of irrigation production systems as well as more sustained and higher valued farm livelihoods. Results show that compared to scenario (1), scenario (2) increases regional farm income by 30%, in which some sub regions secure income gains exceeding 900% compared to base levels. Additional storage is most economically productive when institutional and technical constraints facing irrigated agriculture are dissolved. Along with

  5. Phylogeographic structure and historical demography of the western diamondback rattlesnake (Crotalus atrox): A perspective on North American desert biogeography.

    PubMed

    Castoe, Todd A; Spencer, Carol L; Parkinson, Christopher L

    2007-01-01

    The western diamondback rattlesnake (Crotalus atrox) is a prominent member of North American desert and semi-arid ecosystems, and its importance extends from its impact on the region's ecology and imagery, to its medical relevance as a large deadly venomous snake. We used mtDNA sequences to identify population genetic structure and historical demographic patterns across the range of this species, and relate these to broader patterns of historical biogeography of desert and semi-arid regions of the southwestern USA and adjacent Mexico. We inferred a Late Pliocene divergence between peninsular and continental lineages of Crotalus, followed by an Early Mid Pleistocene divergence across the continental divide within C. atrox. Within desert regions (Sonoran and Chihuahuan Deserts, Southern Plains, and Tamaulipan Plain) we observed population structure indicating isolation of populations in multiple Pleistocene refugia on either side of the continental divide, which we attempt to identify. Evidence of post-glacial population growth and range expansion was inferred, particularly in populations east of the continental divide. We observed clear evidence of (probably recent) gene flow across the continental divide and secondary contact of haplotype lineages. This recent gene flow appears to be particularly strong in the West-to-East direction. Our results also suggest that Crotalus tortugensis (Tortuga Island rattlesnake) and a population of 'C. atrox' inhabiting Santa Cruz Island (in the Gulf of California) previously suggested to be an unnamed species, are in fact deeply phylogenetically nested within continental lineages of C. atrox. Accordingly, we suggest C. tortugensis and 'C. atrox' from Santa Cruz Island be placed in the synonymy of C. atrox. PMID:16934495

  6. Extending the western North American Proterozoic and Paleozoic continental crust through the Mojave Desert

    SciTech Connect

    Martin, M.W.; Walker, J.D. )

    1992-08-01

    Data supporting the existence of Proterozoic basement in the central and western Mojave Desert include U-Pb zircon geochronology and Nd, Sr, and Pb isotopic values of quartzofeldspathic gneisses, detrital zircon provenance ages, and the presence of basement clasts in Paleozoic and Mesozoic conglomerates. These data corroborate existing isotopic data from Mesozoic and Tertiary intrusive rocks that suggest involvement of Proterozoic crust in their genesis. Exposures of Proterozoic basement and Late Proterozoic and Paleozoic transitional miogeoclinal-cratonal facies trends in the central and western Mojave Desert consistently imply that cratonal North America continues westward uninterrupted through this region to the San Andreas fault. These data place geographic limits on the position of several pre-Tertiary tectonic elements speculated to exist in the Mojave Desert.

  7. Record of the North American southwest monsoon from Gulf of Mexico sediment cores

    USGS Publications Warehouse

    Poore, R.Z.; Pavich, M.J.; Grissino-Mayer, H. D.

    2005-01-01

    Summer monsoonal rains (the southwest monsoon) are an important source of moisture for parts of the southwestern United States and northern Mexico. Improved documentation of the variability in the southwest monsoon is needed because changes in the amount and seasonal distribution of precipitation in this semiarid region of North America influence overall water supply and fire severity. Comparison of abundance variations in the planktic foraminifer Globigerinoides sacculifer in marine cores from the western and northern Gulf of Mexico with terrestrial proxy records of precipitation (tree-ring width and packrat-midden occurrences) from the southwestern United States indicate that G. sacculifer abundance is a proxy for the southwest monsoon on millennial and submillennial time scales. The marine record confirms the presence of a severe multicentury drought centered ca. 1600 calendar (cal.) yr B.P. as well as several multidecadal droughts that have been identified in a long tree-ring record spanning the past 2000 cal. yr from westcentral New Mexico. The marine record further suggests that monsoon circulation, and thus summer rainfall, was enhanced in the middle Holocene (ca. 6500-4500 14C yr B.P.; ca. 6980-4710 cal. yr B.P.). The marine proxy provides the potential for constructing a highly resolved, well-dated, and continuous history of the southwest monsoon for the entire Holocene. ?? 2005 Geological Society of America.

  8. Variable effects of cinder-cone eruptions on prehistoric agrarian human populations in the American southwest

    NASA Astrophysics Data System (ADS)

    Ort, Michael H.; Elson, Mark D.; Anderson, Kirk C.; Duffield, Wendell A.; Samples, Terry L.

    2008-10-01

    Two ˜ 900 BP cinder-cone eruptions in the American Southwest affected prehistoric human populations in different ways, mostly because of differences in the eruption styles and area affected. Primary pre-eruption cultural factors that may have led to successful adaptation to the eruptions include decision-making at the family or household level, low investment in site structures, dispersion of agricultural sites in varied environments, and settlement spread over a large area so that those who were less affected could shelter and feed evacuees. Sunset Crater, near Flagstaff, Arizona, produced about 8 km 2 lava flow fields and a ˜ 2300-km 2 tephra blanket in an area that had been settled by prehistoric groups for at least 1000 years. Local subsistence relied on agriculture, primarily maize, and > 30 cm tephra cover rendered 265 km 2 of prime land unfarmable. This area was apparently abandoned for at least several generations. A > 500-km 2 area was probably marked by collapsed roofs and other structural damage from the fallout. If the eruption occurred during the agricultural season, the fallout would also have significantly damaged crops. The eruption did have some benefits to local groups because lower elevation land, which had previously been too dry to farm, became agriculturally productive due to 3-8 cm of tephra 'mulch' and some temporary soil nutrient improvements. This previously uninhabited land became the site of significant year-round settlement and farming, eventually containing some of the largest pueblo structures ever built in the region. New agricultural techniques were developed to manage the fallout mulch. The eruption also affected ceramic production and trading patterns, and volcano-related ritual behavior - the production of maize-impressed lava-spatter agglutinate - was initiated. Little Springs Volcano, about 200 km northwest of Sunset Crater, is a small spatter rampart around a series of vents that produced about 5 km 2 of lava flow fields

  9. South by Southwest: Mexican Americans and Segregated Schooling, 1900-1950.

    ERIC Educational Resources Information Center

    Ruiz, Vicki L.

    2001-01-01

    Addresses school segregation and Mexican Americans, delineating the institutional nature of segregation "for the cause of Americanization." Discusses "Alvarez v. Lemon Grove School District" and "Mendez v. Westminster," two important legal challenges by Mexican American parents on behalf of their children. Includes a bibliography. (CMK)

  10. Ploidy race distributions since the Last Glacial Maximum in the North American desert shrub, Larea tridentata

    USGS Publications Warehouse

    Hunter, Kimberly L.; Betancourt, Julio L.; Riddle, Brett R.; Van Devender, Thomas R.; Cole, K.L.; Spaulding, W.G.

    2001-01-01

    1. A classic biogeographic pattern is the alignment of diploid, tetraploid and hexaploid races of creosote bush (Larrea tridentata) across the Chihuahuan, Sonoran and Mohave Deserts of western North America. We used statistically robust differences in guard cell size of modern plants and fossil leaves from packrat middens to map current and past distributions of these ploidy races since the Last Glacial Maximum (LGM). 2 Glacial/early Holocene (26a??10 14C kyr bp or thousands of radiocarbon years before present) populations included diploids along the lower Rio Grande of west Texas, 650 km removed from sympatric diploids and tetraploids in the lower Colorado River Basin of south-eastern California/south-western Arizona. Diploids migrated slowly from lower Rio Grande refugia with expansion into the northern Chihuahuan Desert sites forestalled until after ~4.0 14C kyr bp. Tetraploids expanded from the lower Colorado River Basin into the northern limits of the Sonoran Desert in central Arizona by 6.4 14C kyr bp. Hexaploids appeared by 8.5 14C kyr bp in the lower Colorado River Basin, reaching their northernmost limits (~37A?N) in the Mohave Desert between 5.6 and 3.9 14C kyr bp. 3 Modern diploid isolates may have resulted from both vicariant and dispersal events. In central Baja California and the lower Colorado River Basin, modern diploids probably originated from relict populations near glacial refugia. Founder events in the middle and late Holocene established diploid outposts on isolated limestone outcrops in areas of central and southern Arizona dominated by tetraploid populations. 4 Geographic alignment of the three ploidy races along the modern gradient of increasingly drier and hotter summers is clearly a postglacial phenomenon, but evolution of both higher ploidy races must have happened before the Holocene. The exact timing and mechanism of polyploidy evolution in creosote bush remains a matter of conjecture.

  11. Ploidy race distributions since the Last Glacial Maximum in the North American desert shrub, Larrea tridentata

    USGS Publications Warehouse

    Hunter, K.L.; Betancourt, J.L.; Riddle, B.R.; Van Devender, T. R.; Cole, K.L.; Geoffrey, Spaulding W.

    2000-01-01

    1 A classic biogeographic pattern is the alignment of diploid, tetraploid and hexaploid races of creosote bush (Larrea tridentata) across the Chihuahuan, Sonoran and Mohave Deserts of western North America. We used statistically robust differences in guard cell size of modern plants and fossil leaves from packrat middens to map current and past distributions of these ploidy races since the Last Glacial Maximum (LGM). 2 Glacial/early Holocene (26-10 14C kyr BP or thousands of radiocarbon years before present) populations included diploids along the lower Rio Grande of west Texas, 650 km removed from sympatric diploids and tetraploids in the lower Colorado River Basin of south-eastern California/south-western Arizona. Diploids migrated slowly from lower Rio Grande refugia with expansion into the northern Chihuahuan Desert sites forestalled until after ???4.0 14C kyr BP. Tetraploids expanded from the lower Colorado River Basin into the northern limits of the Sonoran Desert in central Arizona by 6.4 14C kyr BP. Hexaploids appeared by 8.5 14C kyr BP in the lower Colorado River Basin, reaching their northernmost limits (???37??N) in the Mohave Desert between 5.6 and 3.9 14C kyr BP. 3 Modern diploid isolates may have resulted from both vicariant and dispersal events. In central Baja California and the lower Colorado River Basin, modern diploids probably originated from relict populations near glacial refugia. Founder events in the middle and late Holocene established diploid outposts on isolated limestone outcrops in areas of central and southern Arizona dominated by tetraploid populations. 4 Geographic alignment of the three ploidy races along the modern gradient of increasingly drier and hotter summers is clearly a postglacial phenomenon, but evolution of both higher ploidy races must have happened before the Holocene. The exact timing and mechanism of polyploidy evolution in creosote bush remains a matter of conjecture. ?? 2001 Blackwell Science Ltd.

  12. While on My Journey: A Life Story Analysis of African American Women in Pursuit of Their Doctoral Degrees in the Southwest

    ERIC Educational Resources Information Center

    Manning, Linda

    2013-01-01

    The purpose of this study is to explore the lived experiences of African American women in pursuit of doctoral degrees in the southwest, their challenges and motivations, and plans for the their next chapter. Drawing from critical race theory and a sociocultural framework, this qualitative study uses Dan McAdams' "Life Story Interview"…

  13. 1776-1976: From Revolution to Revelation; Proceedings of the Southwest American Business Communication Association Spring Conference (3rd, San Antonio, Texas, March 17-20, 1976).

    ERIC Educational Resources Information Center

    Bruno, Sam J., Ed.

    The papers included in this document represent most of the papers presented at the 1976 conference of the Southwest American Business Communication Association and deal with various aspects of business communication. Topics of papers are nonverbal aspects of business communication; four problems relating to awareness of metacommunication in…

  14. Silence as Weapons: Transformative Praxis among Native American Students in the Urban Southwest

    ERIC Educational Resources Information Center

    San Pedro, Timothy

    2015-01-01

    This article explores the benefits of verbal conflicts--contested storied spaces--in a Native American literature classroom composed of a multi-tribal and multicultural urban student body. Students in this course engage in whole-class verbal discussions focusing on contemporary and historical issues concerning Native American tribes and…

  15. Exploring Indigenous Identities of Urban American Indian Youth of the Southwest.

    PubMed

    Kulis, Stephen; Wagaman, M Alex; Tso, Crescentia; Brown, Eddie F

    2013-05-01

    This study examined the indigenous identities of urban American Indian youth using measures related to three theoretical dimensions of Markstrom's identity model: identification (tribal and ethnic heritage), connection (reservation ties), and involvement in traditional cultural practices and spirituality. Data came from self-administered questionnaires completed by 142 urban American Indian middle school students in a southwestern metropolitan area with the largest urban American Indian population in the United States. Using both quantitative and qualitative measures, descriptive statistics showed most youth were connected to all three dimensions of indigenous identity. Hierarchical regression analyses showed that youth with the strongest sense of American Indian ethnic identity had native fathers and were heavily involved in traditional cultural practices and spirituality. Although urban American Indians may face challenges in maintaining their tribal identities, the youth in this study appeared strongly moored to their native indigenous heritage. Implications for future research are discussed.

  16. Exploring Indigenous Identities of Urban American Indian Youth of the Southwest

    PubMed Central

    Kulis, Stephen; Wagaman, M. Alex; Tso, Crescentia; Brown, Eddie F.

    2013-01-01

    This study examined the indigenous identities of urban American Indian youth using measures related to three theoretical dimensions of Markstrom's identity model: identification (tribal and ethnic heritage), connection (reservation ties), and involvement in traditional cultural practices and spirituality. Data came from self-administered questionnaires completed by 142 urban American Indian middle school students in a southwestern metropolitan area with the largest urban American Indian population in the United States. Using both quantitative and qualitative measures, descriptive statistics showed most youth were connected to all three dimensions of indigenous identity. Hierarchical regression analyses showed that youth with the strongest sense of American Indian ethnic identity had native fathers and were heavily involved in traditional cultural practices and spirituality. Although urban American Indians may face challenges in maintaining their tribal identities, the youth in this study appeared strongly moored to their native indigenous heritage. Implications for future research are discussed. PMID:23766553

  17. Exploring Indigenous Identities of Urban American Indian Youth of the Southwest.

    PubMed

    Kulis, Stephen; Wagaman, M Alex; Tso, Crescentia; Brown, Eddie F

    2013-05-01

    This study examined the indigenous identities of urban American Indian youth using measures related to three theoretical dimensions of Markstrom's identity model: identification (tribal and ethnic heritage), connection (reservation ties), and involvement in traditional cultural practices and spirituality. Data came from self-administered questionnaires completed by 142 urban American Indian middle school students in a southwestern metropolitan area with the largest urban American Indian population in the United States. Using both quantitative and qualitative measures, descriptive statistics showed most youth were connected to all three dimensions of indigenous identity. Hierarchical regression analyses showed that youth with the strongest sense of American Indian ethnic identity had native fathers and were heavily involved in traditional cultural practices and spirituality. Although urban American Indians may face challenges in maintaining their tribal identities, the youth in this study appeared strongly moored to their native indigenous heritage. Implications for future research are discussed. PMID:23766553

  18. Tree mortality in mature riparian forest: Implications for Fremont cottonwood conservation in the American southwest

    USGS Publications Warehouse

    Andersen, Douglas

    2015-01-01

    Mature tree mortality rates are poorly documented in desert riparian woodlands. I monitored deaths and calculated annual survivorship probability (Ps) in 2 groups of large (27–114 cm DBH), old (≥40 years old) Fremont cottonwood (Populus fremontii Wats.) in a stand along the free-flowing Yampa River in semiarid northwestern Colorado. Ps = 0.993 year-1 in a group (n = 126) monitored over 2003–2013, whereas Ps = 0.985 year-1 in a group (n = 179) monitored over the same period plus 3 earlier years (2000–2003) that included drought and a defoliating insect outbreak. Assuming Ps was the same for both groups during the 10-year postdrought period, the data indicate that Ps = 0.958 year-1 during the drought. I found no difference in canopy dieback level between male and female survivors. Mortality was equal among size classes, suggesting Ps is independent of age, but published longevity data imply that either Ps eventually declines with age or, as suggested in this study, periods with high Ps are interrupted by episodes of increased mortality. Stochastic population models featuring episodes of low Ps suggest a potential for an abrupt decline in mature tree numbers where recruitment is low. The modeling results have implications for woodland conservation, especially for relictual stands along regulated desert rivers.

  19. Mesoscale disturbance and ecological response to decadal climatic variability in the American Southwest

    USGS Publications Warehouse

    Swetnam, T.W.; Betancourt, J.L.

    1998-01-01

    Ecological responses to climatic variability in the Southwest include regionally synchronized fires, insect outbreaks, and pulses in tree demography (births and deaths). Multicentury, tree-ring reconstructions of drought, disturbance history, and tree demography reveal climatic effects across scales, from annual to decadal, and from local (<102 km2) to mesoscale (104-106 km2). Climate-disturbance relations are more variable and complex than previously assumed. During the past three centuries, mesoscale outbreaks of the western spruce budworm (Choristoneura occidentalis) were associated with wet, not dry episodes, contrary to conventional wisdom. Regional fires occur during extreme droughts but, in some ecosystems, antecedent wet conditions play a secondary role by regulating accumulation of fuels. Interdecadal changes in fire-climate associations parallel other evidence for shifts in the frequency or amplitude of the Southern Oscillation (SO) during the past three centuries. High interannual, fire-climate correlations (r = 0.7 to 0.9) during specific decades (i.e., circa 1740-80 and 1830-60) reflect periods of high amplitude in the SO and rapid switching from extreme wet to dry years in the Southwest, thereby entraining fire occurrence across the region. Weak correlations from 1780 to 1830 correspond with a decrease in SO frequency or amplitude inferred from independent tree-ring width, ice core, and coral isotope reconstructions. Episodic dry and wet episodes have altered age structures and species composition of woodland and conifer forests. The scarcity of old, living conifers established before circa 1600 suggests that the extreme drought of 1575-95 had pervasive effects on tree populations. The most extreme drought of the past 400 years occurred in the mid-twentieth century (1942-57). This drought resulted in broadscale plant dieoffs in shrublands, woodlands, and forests and accelerated shrub invasion of grasslands. Drought conditions were broken by the post

  20. Mesoscale Disturbance and Ecological Response to Decadal Climatic Variability in the American Southwest.

    NASA Astrophysics Data System (ADS)

    Swetnam, Thomas W.; Betancourt, Julio L.

    1998-12-01

    Ecological responses to climatic variability in the Southwest include regionally synchronized fires, insect outbreaks, and pulses in tree demography (births and deaths). Multicentury, tree-ring reconstructions of drought, disturbance history, and tree demography reveal climatic effects across scales, from annual to decadal, and from local (<102 km2) to mesoscale (104-106 km2). Climate-disturbance relations are more variable and complex than previously assumed. During the past three centuries, mesoscale outbreaks of the western spruce budworm (Choristoneura occidentalis) were associated with wet, not dry episodes, contrary to conventional wisdom. Regional fires occur during extreme droughts but, in some ecosystems, antecedent wet conditions play a secondary role by regulating accumulation of fuels. Interdecadal changes in fire-climate associations parallel other evidence for shifts in the frequency or amplitude of the Southern Oscillation (SO) during the past three centuries. High interannual, fire-climate correlations (r = 0.7 to 0.9) during specific decades (i.e., circa 1740-80 and 1830-60) reflect periods of high amplitude in the SO and rapid switching from extreme wet to dry years in the Southwest, thereby entraining fire occurrence across the region. Weak correlations from 1780 to 1830 correspond with a decrease in SO frequency or amplitude inferred from independent tree-ring width, ice core, and coral isotope reconstructions.Episodic dry and wet episodes have altered age structures and species composition of woodland and conifer forests. The scarcity of old, living conifers established before circa 1600 suggests that the extreme drought of 1575-95 had pervasive effects on tree populations. The most extreme drought of the past 400 years occurred in the mid-twentieth century (1942-57). This drought resulted in broadscale plant dieoffs in shrublands, woodlands, and forests and accelerated shrub invasion of grasslands. Drought conditions were broken by the post

  1. Preserving Southwest Virginia's Folklore.

    ERIC Educational Resources Information Center

    Burgin, Ramond

    1997-01-01

    Describes Southwest Virginia's rich tradition of folklore and culture and the need for its preservation. Summarizes the author's time-consuming process of preparing an inventory and indexing the vast archival collections gathered by students in American Folklore classes at Mountain Empire Community College and by the Southwest Virginia Folklore…

  2. Southwest: A Simulation of the Spanish/Mexican Influence upon American History.

    ERIC Educational Resources Information Center

    Callis, Jan

    This simulation allows students to learn of the shared Hispanic background of the Southwestern states and help students realize that the states developed in a parallel fashion, not in isolation. The packet is divided into eight sections: (1) "Introduction"; (2) "Land"; (3) "Native Americans"; (4) "Explorers"; (5) "Missions/Settlements"; (6)…

  3. Exploring Indigenous Identities of Urban American Indian Youth of the Southwest

    ERIC Educational Resources Information Center

    Kulis, Stephen; Wagaman, M. Alex; Tso, Crescentia; Brown, Eddie F.

    2013-01-01

    This study examined the indigenous identities of urban American Indian youth using measures related to three theoretical dimensions of Markstrom's identity model: identification (tribal and ethnic heritage), connection (reservation ties), and involvement in traditional cultural practices and spirituality. Data came from self-administered…

  4. MyPyramid.gov knowledge and access among rural southwest Mississippi African American adolescents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study used a qualitative approach to identify knowledge of food recommendations found on MyPyramid.gov and access to MyPyramid.gov among limited-income African American youth. We conducted 5 single-sex focus groups with 9 boys and 30 girls (grades 5th and 6th). Data processing and analysis incl...

  5. Southwest Cardiovascular Curriculum Project: Study Findings for American Indian Elementary Students.

    ERIC Educational Resources Information Center

    Davis, Sally M.; And Others

    1995-01-01

    This article describes the Southwestern Cardiovascular Curriculum, a school-based, culturally relevant curriculum designed to prevent tobacco use and promote a good diet. Comparisons of American Indian students in participating and nonparticipating schools indicated that participants had significant increases in knowledge, better diets, increased…

  6. SPANISH IN THE SOUTHWEST.

    ERIC Educational Resources Information Center

    SANCHEZ, GEORGE I.

    IN THE AMERICAN SOUTHWEST, FOUR MILLION SPANISH-AMERICANS ARE CONCENTRATED IN FIVE STATES. THEIR CULTURAL TENACITY IS A PECULIARITY NOT DISPLAYED BY OTHER IMMIGRANT GROUPS. EVEN AFTER 125 YEARS THEY SPEAK AND LIVE IN A SPANISH-AMERICAN SOCIETY. THE REASON FOR THIS IS DIFFICULT TO DISCERN, BUT IT IS FELT BY SOME THAT THIS TENACITY IS VERY NOBLE AND…

  7. The Desert Laboratory Repeat Photography Collection - An Invaluable Archive Documenting Landscape Change

    USGS Publications Warehouse

    Webb, Robert H.; Boyer, Diane E.; Turner, Raymond M.; Bullock, Stephen H.

    2007-01-01

    The Desert Laboratory Repeat Photography Collection, the largest collection of its kind in the world, is housed at the U.S. Geological Survey (USGS) in Tucson, Arizona. The collection preserves thousands of photos taken precisely in the same places but at different times. This archive of 'repeat photographs' documents changes in the desert landscape and vegetation of the American Southwest, and also includes images from northwestern Mexico and Kenya. These images are an invaluable asset to help understand the effects of climate variation and land-use practices on arid and semiarid environments.

  8. AN APPROACH FOR DETERMINING REGIONAL LAND COVER AND SPECIES HABITAT DISTRIBUTIONS IN THE AMERICAN SOUTHWEST: THE SOUTHWEST REGIONAL GAP ANALYSIS PROJECT

    EPA Science Inventory

    The Southwest Regional Gap Analysis Project (SWReGAP) is developing seamless digital coverages for land cover, vertebrate animal habitat, and land management status for the 5-state region of Nevada, Arizona, Utah, New Mexico, and Colorado. The project is a second generation effor...

  9. Unprecedented 21st century drought risk in the American Southwest and Central Plains

    NASA Astrophysics Data System (ADS)

    Cook, B.; Ault, T.; Smerdon, J. E.

    2015-12-01

    In the Southwest and Central Plains of Western North America, climate change is expected to increase drought severity in the coming decades. These regions nevertheless experienced extended Medieval-era droughts that were more persistent than any historical event, providing crucial targets in the paleoclimate record for benchmarking the severity of future drought risks. We use an empirical drought reconstruction and three soil moisture metrics from 17 state-of-the-art general circulation models to show that these models project significantly drier conditions in the later half of the 21st century compared to the 20th century and earlier paleoclimatic intervals. This desiccation is consistent across most of the models and moisture balance variables, indicating a coherent and robust drying response to warming despite the diversity of models and metrics analyzed. Notably, future drought risk will likely exceed even the driest centuries of the Medieval Climate Anomaly (1100-1300 CE) in both moderate (RCP 4.5) and high (RCP 8.5) future emissions scenarios, leading to unprecedented drought conditions during the last millennium.

  10. Unprecedented 21st century drought risk in the American Southwest and Central Plains

    PubMed Central

    Ault, Toby R.; Smerdon, Jason E.

    2015-01-01

    In the Southwest and Central Plains of Western North America, climate change is expected to increase drought severity in the coming decades. These regions nevertheless experienced extended Medieval-era droughts that were more persistent than any historical event, providing crucial targets in the paleoclimate record for benchmarking the severity of future drought risks. We use an empirical drought reconstruction and three soil moisture metrics from 17 state-of-the-art general circulation models to show that these models project significantly drier conditions in the later half of the 21st century compared to the 20th century and earlier paleoclimatic intervals. This desiccation is consistent across most of the models and moisture balance variables, indicating a coherent and robust drying response to warming despite the diversity of models and metrics analyzed. Notably, future drought risk will likely exceed even the driest centuries of the Medieval Climate Anomaly (1100–1300 CE) in both moderate (RCP 4.5) and high (RCP 8.5) future emissions scenarios, leading to unprecedented drought conditions during the last millennium. PMID:26601131

  11. Southwest History. [Sahuarita High School Career Curriculum Project].

    ERIC Educational Resources Information Center

    Hoffman, Judy

    A course on South west history part of a high school career curriculum project, is outlined. Objectives for each part of the course are listed. Course titles include: Urban Problems in the Southwest, Mexican Americans in the Southwest, Southwest History, Americans in the Southwest, Indians in the Southwest, Urban Problems, and History of Business…

  12. Wither the Fruited Plain: The Long Expedition and the Description of the "Great American Desert"

    ERIC Educational Resources Information Center

    Sweeney, Kevin Z.

    2005-01-01

    The view from Pikes Peak is breathtaking. In the summer of 1893, Katherine Lee Bates sat on the summit of Pikes Peak, inspired by the panorama to pen the words to "America the Beautiful." Her poem was set to the tune "Materna" by Samuel Augustus Ward two years later to become one of our nation's most beloved anthems. Many educated Americans in the…

  13. Sensitivity of aquatic ecosystems to climatic and anthropogenic changes: The basin and range, American Southwest and Mexico

    USGS Publications Warehouse

    Grimm, N. B.; Chacon, A.; Dahm, Clifford N.; Hostetler, S.W.; Lind, O.T.; Starkweather, P.L.; Wurtsbaugh, W.W.

    1997-01-01

    Variability and unpredictability are characteristics of the aquatic ecosystems, hydrological patterns and climate of the largely dryland region that encompasses the Basin and Range, American Southwest and western Mexico. Neither hydrological nor climatological models for the region are sufficiently developed to describe the magnitude or direction of change in response to increased carbon dioxide; thus, an attempt to predict specific responses of aquatic ecosystems is premature. Instead, we focus on the sensitivity of rivers, streams, springs, wetlands, reservoirs, and lakes of the region to potential changes in climate, especially those inducing a change in hydrological patterns such as amount, timing and predictability of stream flow. The major sensitivities of aquatic ecosystems are their permanence and even existence in the face of potential reduced net basin supply of water, stability of geomorphological structure and riparian ecotones with alterations in disturbance regimes, and water quality changes resulting from a modified water balance. In all of these respects, aquatic ecosystems of the region are also sensitive to the extensive modifications imposed by human use of water resources, which underscores the difficulty of separating this type of anthropogenic change from climate change. We advocate a focus in future research on reconstruction and analysis of past climates and associated ecosystem characteristics, long-term studies to discriminate directional change vs. year to year variability (including evidence of aquatic ecosystem responses or sensitivity to extremes), and studies of ecosystems affected by human activity. ?? 1997 by John Wiley & Sons, Ltd.

  14. Stream hierarchy defines riverscape genetics of a North American desert fish.

    PubMed

    Hopken, Matthew W; Douglas, Marlis R; Douglas, Michael E

    2013-02-01

    Global climate change is apparent within the Arctic and the south-western deserts of North America, with record drought in the latter reflected within 640,000 km(2) of the Colorado River Basin. To discern the manner by which natural and anthropogenic drivers have compressed Basin-wide fish biodiversity, and to establish a baseline for future climate effects, the Stream Hierarchy Model (SHM) was employed to juxtapose fluvial topography against molecular diversities of 1092 Bluehead Sucker (Catostomus discobolus). MtDNA revealed three geomorphically defined evolutionarily significant units (ESUs): Bonneville Basin, upper Little Colorado River and the remaining Colorado River Basin. Microsatellite analyses (16 loci) reinforced distinctiveness of the Bonneville Basin and upper Little Colorado River, but subdivided the Colorado River Basin into seven management units (MUs). One represents a cline of three admixed gene pools comprising the mainstem and its lower-gradient tributaries. Six others are not only distinct genetically but also demographically (i.e. migrants/generation <9.7%). Two of these (i.e. Grand Canyon and Canyon de Chelly) are defined by geomorphology, two others (i.e. Fremont-Muddy and San Raphael rivers) are isolated by sharp declivities as they drop precipitously from the west slope into the mainstem Colorado/Green rivers, another represents an isolated impoundment (i.e. Ringdahl Reservoir), while the last corresponds to a recognized subspecies (i.e. Zuni River, NM). Historical legacies of endemic fishes (ESUs) and their evolutionary potential (MUs) are clearly represented in our data, yet their arbiter will be the unrelenting natural and anthropogenic water depletions that will precipitate yet another conservation conflict within this unique but arid region. PMID:23279045

  15. Mutation analysis of the cystic fibrosis transmembrane regulator gene in native American populations of the southwest

    SciTech Connect

    Grebe, T.A. Maricopa Medical Center, Phoenix, AZ ); Doane, W.W.; Norman, R.A.; Rhodes, S.N. ); Richter, S.F. ); Clericuzio, C. ); Seltzer, W.K. ); Goldberg, B.E. ); Hernried, L.S. ); McClure, M.; Kaplan, G.

    1992-10-01

    The authors report DNA and clinical analysis of cystic fibrosis (CF) in two previously unstudied, genetically isolated populations: Pueblo and Navajo Native Americans. Direct mutation analysis of six mutations of the CFTR gene - namely, [Delta]F508, G542X, G551D, R553X, N1303K, and W1282X - was performed on PCR-amplified genomic DNA extracted from blood samples. Haplotype analyses with marker/enzyme pairs XV2c/TaqI and KM29/PstI were performed as well. Of the 12 affected individuals studied, no [Delta]F508 mutation was detected; only one G542X mutation was found. None of the other mutations was detected. All affected individuals have either an AA, AC, or CC haplotype, except for the one carrying the G542X mutation, who has the haplotye AB. Clinically, six of the affected individuals examined exhibit growth deficiency, and five (all from the Zuni Pueblo) have a severe CF phenotype. Four of the six Zunis with CF are also microcephalic, a finding not previously noted in CF patients. The DNA data have serious implications for risk assessment of CF carrier status for these people. 14 refs., 3 tabs.

  16. Wood decay in desert riverine environments

    USGS Publications Warehouse

    Andersen, Douglas; Stricker, Craig A.; Nelson, S. Mark

    2016-01-01

    , local weather, and especially the regional climate through its effect on the flow regime. The increased warmth and aridity expected to accompany climate change in the North American southwest will likely retard the already slow wood decay process on naturally functioning desert river floodplains. Our results have implications for designing environmental flows to manage floodplain forest wood budgets, carbon storage, and nutrient cycling along regulated dryland rivers.

  17. Flash flood causing mechanisms of the North American Monsoon System in the Sonoran Desert

    NASA Astrophysics Data System (ADS)

    Bieda, Stephen Walter, III

    The North American Monsoon System (NAMS) is a significant weather and climate phenomenon that brings critical rainfall to the southwestern United States and northwestern Mexico. As a result of the North American Monsoon Experiment, and research efforts surrounding the field campaign, the understanding of the NAMS has increased considerably over the last 15 years. In addition questions concerning potential flash flood causing mechanisms of the NAMS have not been thoroughly investigated. This dissertation is comprised of two papers that collectively address the aspects of the literary understanding of the NAMS as we know it today and conduct an investigation into the complex interactions between various weather systems that may influence the NAMS. In the first paper, a review of the major research of the NAMS literature since the last comprehensive review 15 years ago is conducted. The results of his review are assessed for where our understanding has been improved and where future research needs to be guided for purposes of the second paper. Based upon the results from the literature review, the second paper focuses on identification of inverted troughs and gulf surges based upon lower- and mid-level atmospheric parameters for purposes of assessing the impacts on National Weather Service Storm Report flash flood dates. This research contributes to the synthesis of the current knowledge of the NAMS in general and to the specific regional impacts that do occur during periods of heavy precipitation over the NAMS region for purposes of improving meteorological predictability of flash flooding. The results can (1) gauge our understanding of the NAMS literature to date and (2) improve meteorological forecasts through the recognition of synoptic and sub-synoptic patterns related to the NAMS that are most likely to cause flash floods.

  18. Interaction of the terrestrial and atmospheric hydrological cycles in the context of the North American southwest summer monsoon

    NASA Technical Reports Server (NTRS)

    Dickinson, Robert E.

    1995-01-01

    flux divergence of water vapor from ECMWF data, most moisture at upper levels arrives from the Gulf of Mexico, while low level moisture comes from the northern Gulf of California. Composites of ECMWF analyses for wet and dry periods (classified by rain gauge data) show that both regimes show low level moisture arriving from northern and central Gulf of California. Above 700 MB, moisture comes from both source regions and the Sierra Madre Occidental. During wet periods a longer fetch through the moist air mass above western Mexico results in a greater moisture flux into the Sonoran Desert region, while there is less moisture from the Gulf of Mexico both above and below 700 mb. Work on the grant subcontract at the University of Colorado concentrated on the development of a technique useful to TRMM combining visible, infrared and passive microwave data for measuring precipitation. Two established techniques using either visible or infrared data applied over the US Southwest correlated with gauges at the 0.58 to 0.70 level. The application of some established passive microwave techniques were less successful for a variety of reason, including problems in both the gauge and satellite data quality, sampling problems and weaknesses inherent in the algorithms themselves. A more promising solution for accurate rainfall estimation was explored using visible and infrared data to perform a cloud classification, which when combined with information about the background (e.g. Iand/ocean), was used to select the most appropriate microwave algorithm from a suite of possibilities.

  19. Farming the Desert: agriculture in the World War II-era Japanese-American relocation centers.

    PubMed

    Lillquist, Karl

    2010-01-01

    In 1942 over 110,000 Japanese Americans were evacuated from the West Coast to ten inland, barbed wire-enclosed relocation centers in the name of national security. Agriculture was a key component of the eight arid to semi-arid centers located in the western United States. Each center's agricultural program included produce for human consumption, feed crops, and livestock. Some centers also grew seed, ornamental, and war crops. Evacuees raised and consumed five types of livestock and sixty-one produce varieties, including many traditional foods. Seasonal surpluses were preserved, shipped to other centers, or sold on the open market. Short growing seasons, poor soils, initially undeveloped lands, pests, equipment shortages, and labor issues hampered operations. However, imprisoned evacuee farmers proved that diverse agricultural programs could succeed in the harsh settings primarily because of labor-intensive farming methods, ingenuity, and the large markets provided by the centers. These agricultural programs played major roles in feeding, providing meaningful employment, and preparing evacuees for life outside the centers, and readied lands for post-war "homesteaders."

  20. Farming the Desert: agriculture in the World War II-era Japanese-American relocation centers.

    PubMed

    Lillquist, Karl

    2010-01-01

    In 1942 over 110,000 Japanese Americans were evacuated from the West Coast to ten inland, barbed wire-enclosed relocation centers in the name of national security. Agriculture was a key component of the eight arid to semi-arid centers located in the western United States. Each center's agricultural program included produce for human consumption, feed crops, and livestock. Some centers also grew seed, ornamental, and war crops. Evacuees raised and consumed five types of livestock and sixty-one produce varieties, including many traditional foods. Seasonal surpluses were preserved, shipped to other centers, or sold on the open market. Short growing seasons, poor soils, initially undeveloped lands, pests, equipment shortages, and labor issues hampered operations. However, imprisoned evacuee farmers proved that diverse agricultural programs could succeed in the harsh settings primarily because of labor-intensive farming methods, ingenuity, and the large markets provided by the centers. These agricultural programs played major roles in feeding, providing meaningful employment, and preparing evacuees for life outside the centers, and readied lands for post-war "homesteaders." PMID:20419893

  1. Differences in cigarette and smokeless tobacco use among American Indian and Alaska Native people living in Alaska and the Southwest United States

    PubMed Central

    Lanier, Anne P.; Renner, Caroline; Smith, Julia; Tom-Orme, Lillian; Slattery, Martha L.

    2010-01-01

    Introduction: This study analyzed self-reported tobacco use among American Indian and Alaska Native (AI/AN) people enrolled in the Education and Research Towards Health Study in Alaska (n = 3,821) and the Southwest United States (n = 7,505) from 2004 to 2006. Methods: Participants (7,060 women and 4,266 men) completed a computer-assisted self-administered questionnaire on cigarette and smokeless tobacco (ST) use. Results: Current use of cigarettes was considerably higher in Alaska than in the Southwest United States (32% vs. 8%). Current ST use was also more common in Alaska than in the Southwest United States (18% vs. 8%). Additionally, smoking was more common among men, younger age, those who were not married, and who only spoke English at home, while ST use was more common among men, those with lower educational attainment and those who spoke an AI/AN language at home (p < .01). Compared with the U.S. general population, AI/AN people living in Alaska were more likely and those living in the Southwest United States were less likely to be current smokers. Rates of ST use, including homemade ST, in both regions were much higher than the U.S. general population. Discussion: Tobacco use among AI/AN people in the Southwest United States, who have a tradition of ceremonial tobacco use, was far lower than among Alaska Native people, who do not have a tribal tradition. Tobacco use is a key risk factor for multiple diseases. Reduction of tobacco use is a critical prevention measure to improve the health of AI/AN people. PMID:20525781

  2. Desert wetlands—Archives of a wetter past

    USGS Publications Warehouse

    Pigati, Jeffery S.; Springer, Kathleen B.; Manker, Craig R.

    2015-12-16

    Scientists from the U.S. Geological Survey (USGS) are finding evidence of a much wetter past in the deserts of the American Southwest using a most unlikely source—wetlands. Wetlands form in arid environments where water tables approach or breach the ground surface. Often thought of as stagnant and unchanging, new evidence suggests that springs and wetlands responded dynamically to past episodes of abrupt climate change. Multiple cycles of deposition, erosion, and soil formation show that wetlands in the southwestern United States expanded and contracted many times during the past 35,000 years or so, before disappearing altogether as the last glacial period came to a close. USGS scientists are now studying the deposits to determine how closely conditions in the desert were tied to regional and global climate patterns in the past, and what it might mean for the fragile ecosystems in light of anticipated climate change in the future.

  3. Turbines and terrestrial vertebrates: variation in tortoise survivorship between a wind energy facility and an adjacent undisturbed wildland area in the desert southwest (USA)

    USGS Publications Warehouse

    Agha, Mickey; Lovich, Jeffrey E.; Ennen, Joshua R.; Augustine, Benjamin J.; Arundel, Terry; Murphy, Mason O.; Meyer-Wilkins, Kathie; Bjurlin, Curtis; Delaney, David F.; Briggs, Jessica; Austin, Meaghan; Madrak, Sheila V.; Price, Steven J.

    2015-01-01

    With the recent increase in utility-scale wind energy development, researchers have become increasingly concerned how this activity will affect wildlife and their habitat. To understand the potential impacts of wind energy facilities (WEF) post-construction (i.e., operation and maintenance) on wildlife, we compared differences in activity centers and survivorship of Agassiz's desert tortoises (Gopherus agassizii) inside or near a WEF to neighboring tortoises living near a wilderness area (NWA) and farther from the WEF. We found that the size of tortoise activity centers varied, but not significantly so, between the WEF (6.25 ± 2.13 ha) and adjacent NWA (4.13 ± 1.23 ha). However, apparent survival did differ significantly between the habitat types: over the 18 year study period apparent annual survival estimates were 0.96 ± 0.01 for WEF tortoises and 0.92 ± 0.02 for tortoises in the NWA. High annual survival suggests that operation and maintenance of the WEF has not caused considerable declines in the adult population over the past two decades. Low traffic volume, enhanced resource availability and decreased predator populations may influence annual survivorship at this WEF. Further research on these proximate mechanisms and population recruitment would be useful for mitigating and managing post-development impacts of utility scale wind energy on long-lived terrestrial vertebrates.

  4. Turbines and Terrestrial Vertebrates: Variation in Tortoise Survivorship Between a Wind Energy Facility and an Adjacent Undisturbed Wildland Area in the Desert Southwest (USA).

    PubMed

    Agha, Mickey; Lovich, Jeffrey E; Ennen, Joshua R; Augustine, Benjamin; Arundel, Terence R; Murphy, Mason O; Meyer-Wilkins, Kathie; Bjurlin, Curtis; Delaney, David; Briggs, Jessica; Austin, Meaghan; Madrak, Sheila V; Price, Steven J

    2015-08-01

    With the recent increase in utility-scale wind energy development, researchers have become increasingly concerned how this activity will affect wildlife and their habitat. To understand the potential impacts of wind energy facilities (WEF) post-construction (i.e., operation and maintenance) on wildlife, we compared differences in activity centers and survivorship of Agassiz's desert tortoises (Gopherus agassizii) inside or near a WEF to neighboring tortoises living near a wilderness area (NWA) and farther from the WEF. We found that the size of tortoise activity centers varied, but not significantly so, between the WEF (6.25 ± 2.13 ha) and adjacent NWA (4.13 ± 1.23 ha). However, apparent survival did differ significantly between the habitat types: over the 18-year study period apparent annual survival estimates were 0.96 ± 0.01 for WEF tortoises and 0.92 ± 0.02 for tortoises in the NWA. High annual survival suggests that operation and maintenance of the WEF has not caused considerable declines in the adult population over the past two decades. Low traffic volume, enhanced resource availability, and decreased predator populations may influence annual survivorship at this WEF. Further research on these proximate mechanisms and population recruitment would be useful for mitigating and managing post-development impacts of utility-scale wind energy on long-lived terrestrial vertebrates. PMID:25894273

  5. Turbines and Terrestrial Vertebrates: Variation in Tortoise Survivorship Between a Wind Energy Facility and an Adjacent Undisturbed Wildland Area in the Desert Southwest (USA)

    NASA Astrophysics Data System (ADS)

    Agha, Mickey; Lovich, Jeffrey E.; Ennen, Joshua R.; Augustine, Benjamin; Arundel, Terence R.; Murphy, Mason O.; Meyer-Wilkins, Kathie; Bjurlin, Curtis; Delaney, David; Briggs, Jessica; Austin, Meaghan; Madrak, Sheila V.; Price, Steven J.

    2015-08-01

    With the recent increase in utility-scale wind energy development, researchers have become increasingly concerned how this activity will affect wildlife and their habitat. To understand the potential impacts of wind energy facilities (WEF) post-construction (i.e., operation and maintenance) on wildlife, we compared differences in activity centers and survivorship of Agassiz's desert tortoises ( Gopherus agassizii) inside or near a WEF to neighboring tortoises living near a wilderness area (NWA) and farther from the WEF. We found that the size of tortoise activity centers varied, but not significantly so, between the WEF (6.25 ± 2.13 ha) and adjacent NWA (4.13 ± 1.23 ha). However, apparent survival did differ significantly between the habitat types: over the 18-year study period apparent annual survival estimates were 0.96 ± 0.01 for WEF tortoises and 0.92 ± 0.02 for tortoises in the NWA. High annual survival suggests that operation and maintenance of the WEF has not caused considerable declines in the adult population over the past two decades. Low traffic volume, enhanced resource availability, and decreased predator populations may influence annual survivorship at this WEF. Further research on these proximate mechanisms and population recruitment would be useful for mitigating and managing post-development impacts of utility-scale wind energy on long-lived terrestrial vertebrates.

  6. Turbines and Terrestrial Vertebrates: Variation in Tortoise Survivorship Between a Wind Energy Facility and an Adjacent Undisturbed Wildland Area in the Desert Southwest (USA).

    PubMed

    Agha, Mickey; Lovich, Jeffrey E; Ennen, Joshua R; Augustine, Benjamin; Arundel, Terence R; Murphy, Mason O; Meyer-Wilkins, Kathie; Bjurlin, Curtis; Delaney, David; Briggs, Jessica; Austin, Meaghan; Madrak, Sheila V; Price, Steven J

    2015-08-01

    With the recent increase in utility-scale wind energy development, researchers have become increasingly concerned how this activity will affect wildlife and their habitat. To understand the potential impacts of wind energy facilities (WEF) post-construction (i.e., operation and maintenance) on wildlife, we compared differences in activity centers and survivorship of Agassiz's desert tortoises (Gopherus agassizii) inside or near a WEF to neighboring tortoises living near a wilderness area (NWA) and farther from the WEF. We found that the size of tortoise activity centers varied, but not significantly so, between the WEF (6.25 ± 2.13 ha) and adjacent NWA (4.13 ± 1.23 ha). However, apparent survival did differ significantly between the habitat types: over the 18-year study period apparent annual survival estimates were 0.96 ± 0.01 for WEF tortoises and 0.92 ± 0.02 for tortoises in the NWA. High annual survival suggests that operation and maintenance of the WEF has not caused considerable declines in the adult population over the past two decades. Low traffic volume, enhanced resource availability, and decreased predator populations may influence annual survivorship at this WEF. Further research on these proximate mechanisms and population recruitment would be useful for mitigating and managing post-development impacts of utility-scale wind energy on long-lived terrestrial vertebrates.

  7. Modeling Soil Moisture in the Mojave Desert

    USGS Publications Warehouse

    Miller, David M.; Hughson, Debra; Schmidt, Kevin M.

    2008-01-01

    The Mojave Desert is an arid region of southeastern California and parts of Nevada, Arizona, and Utah; the desert occupies more than 25,000 square miles (fig. 1). Ranging from below sea level to over 5,000 feet (1,524 m) in elevation, the Mojave Desert is considered a ?high desert.? On the west and southwest it is bounded by the Sierra Nevada, the San Gabriel, and the San Bernardino Mountains. These imposing mountains intercept moisture traveling inland from the Pacific Ocean, producing arid conditions characterized by extreme fluctuations in daily temperatures, strong seasonal winds, and an average annual precipitation of less than six inches. The Mojave Desert lies farther south and at a lower elevation than the cooler Great Basin Desert and grades southward into the even lower and hotter Sonoran Desert.

  8. Sociocultural barriers to medical care among Mexican Americans in Texas: a summary report of research conducted by the Southwest Medical Sociology Ad Hoc Committee.

    PubMed

    Quesada, G M; Heller, P L

    1977-05-01

    This paper summarizes research findings from members of the Southwest Medical Sociology Ad Hoc Committee concerning sociocultural barriers to medical care among Mexican Americans in Texas. Committee members individually, or in two-person groups, studied a number of factors concerning Mexican-American medical care in Texas such as: 1) mortality, morbidity, and other health status indicators; 2) health manpower and educational needs; 3) political factors impeding economical health care; 4) alienation, familism, and their relationship to utilization of the health services; 5) language and communication barriers; and 6) folk medicine. Findings include documentation that structural alienation of Mexican-Americans from mainstream Anglo-American middle-class society is carried over into their relation with utilization of the health care delivery system; that their emphasis on familism works alternatively to encourage and discourage their seeking access to health care; the language differences serve to perpetuate certain cultural differences that are inimical to health care delivery; and that curanderismo can be seen as complementing other types of health care. The report concludes with a number of recommendations for accomplishing cultural integration that will lead to better care for this segment of the health population. PMID:857103

  9. Sociocultural barriers to medical care among Mexican Americans in Texas: a summary report of research conducted by the Southwest Medical Sociology Ad Hoc Committee.

    PubMed

    Quesada, G M; Heller, P L

    1977-05-01

    This paper summarizes research findings from members of the Southwest Medical Sociology Ad Hoc Committee concerning sociocultural barriers to medical care among Mexican Americans in Texas. Committee members individually, or in two-person groups, studied a number of factors concerning Mexican-American medical care in Texas such as: 1) mortality, morbidity, and other health status indicators; 2) health manpower and educational needs; 3) political factors impeding economical health care; 4) alienation, familism, and their relationship to utilization of the health services; 5) language and communication barriers; and 6) folk medicine. Findings include documentation that structural alienation of Mexican-Americans from mainstream Anglo-American middle-class society is carried over into their relation with utilization of the health care delivery system; that their emphasis on familism works alternatively to encourage and discourage their seeking access to health care; the language differences serve to perpetuate certain cultural differences that are inimical to health care delivery; and that curanderismo can be seen as complementing other types of health care. The report concludes with a number of recommendations for accomplishing cultural integration that will lead to better care for this segment of the health population.

  10. Use of Anecdotal Occurrence Data in Species Distribution Models: An Example Based on the White-Nosed Coati (Nasua narica) in the American Southwest

    PubMed Central

    Frey, Jennifer K.; Lewis, Jeremy C.; Guy, Rachel K.; Stuart, James N.

    2013-01-01

    Simple Summary We evaluated the influence of occurrence records with different reliability on predicted distribution of a unique, rare mammal in the American Southwest, the white-nosed coati (Nasua narica). We concluded that occurrence datasets that include anecdotal records can be used to infer species distributions, providing such data are used only for easily-identifiable species and based on robust modeling methods such as maximum entropy. Use of a reliability rating system is critical for using anecdotal data. Abstract Species distributions are usually inferred from occurrence records. However, these records are prone to errors in spatial precision and reliability. Although influence of spatial errors has been fairly well studied, there is little information on impacts of poor reliability. Reliability of an occurrence record can be influenced by characteristics of the species, conditions during the observation, and observer’s knowledge. Some studies have advocated use of anecdotal data, while others have advocated more stringent evidentiary standards such as only accepting records verified by physical evidence, at least for rare or elusive species. Our goal was to evaluate the influence of occurrence records with different reliability on species distribution models (SDMs) of a unique mammal, the white-nosed coati (Nasua narica) in the American Southwest. We compared SDMs developed using maximum entropy analysis of combined bioclimatic and biophysical variables and based on seven subsets of occurrence records that varied in reliability and spatial precision. We found that the predicted distribution of the coati based on datasets that included anecdotal occurrence records were similar to those based on datasets that only included physical evidence. Coati distribution in the American Southwest was predicted to occur in southwestern New Mexico and southeastern Arizona and was defined primarily by evenness of climate and Madrean woodland and chaparral land

  11. Who is Offering and How Often? Gender Differences in Drug Offers among American Indian Adolescents of the Southwest

    ERIC Educational Resources Information Center

    Rayle, Andrea Dixon; Kulis, Stephen; Okamoto, Scott K.; Tann, Sheila S.; LeCroy, Craig Winston; Dustman, Patricia; Burke, Aimee M.

    2006-01-01

    This exploratory study examined gender differences in the patterns of drug offers among a sample of 71 American Indian middle school students. Participants responded to an inventory of drug-related problem situations specific to the cultural contexts of Southwestern American Indian youth. They were asked to consider the frequency of drug offers…

  12. Use of Anecdotal Occurrence Data in Species Distribution Models: An Example Based on the White-Nosed Coati (Nasua narica) in the American Southwest.

    PubMed

    Frey, Jennifer K; Lewis, Jeremy C; Guy, Rachel K; Stuart, James N

    2013-01-01

    Species distributions are usually inferred from occurrence records. However, these records are prone to errors in spatial precision and reliability. Although influence of spatial errors has been fairly well studied, there is little information on impacts of poor reliability. Reliability of an occurrence record can be influenced by characteristics of the species, conditions during the observation, and observer's knowledge. Some studies have advocated use of anecdotal data, while others have advocated more stringent evidentiary standards such as only accepting records verified by physical evidence, at least for rare or elusive species. Our goal was to evaluate the influence of occurrence records with different reliability on species distribution models (SDMs) of a unique mammal, the white-nosed coati (Nasua narica) in the American Southwest. We compared SDMs developed using maximum entropy analysis of combined bioclimatic and biophysical variables and based on seven subsets of occurrence records that varied in reliability and spatial precision. We found that the predicted distribution of the coati based on datasets that included anecdotal occurrence records were similar to those based on datasets that only included physical evidence. Coati distribution in the American Southwest was predicted to occur in southwestern New Mexico and southeastern Arizona and was defined primarily by evenness of climate and Madrean woodland and chaparral land-cover types. Coati distribution patterns in this region suggest a good model for understanding the biogeographic structure of range margins. We concluded that occurrence datasets that include anecdotal records can be used to infer species distributions, providing such data are used only for easily-identifiable species and based on robust modeling methods such as maximum entropy. Use of a reliability rating system is critical for using anecdotal data.

  13. Interior view to the southwest of Computer Room 157 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view to the southwest of Computer Room 157 - Over-the-Horizon Backscatter Radar Network, Mountain Home Air Force Operations Building, On Desert Street at 9th Avenue Mountain Home Air Force Base, Mountain Home, Elmore County, ID

  14. Ecophysiology of two Sonoran Desert evergreen shrubs during extreme drought

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent drought across the arid Southwest US may be especially problematic for evergreen desert species that maintain leaves through dry periods. In July, 2002 we compared the ecophysiogical performance of the microphyllous creosotebush (Larrea tridentata) to broadleaved jojoba (Simmondisa chinensis...

  15. Desert Communities.

    ERIC Educational Resources Information Center

    NatureScope, 1985

    1985-01-01

    Provides: (1) background information on desert communities, their similarities, and differences; (2) student activities on this topic; and (3) ready-to-copy student pages with pictures of desert animals and plants. Each activity includes objective(s), recommended age level(s), subject area(s), list of materials needed, and procedures. (DH)

  16. Intimate Partner Violence and Alcohol, Drug, and Mental Disorders among American Indian Women from Southwest Tribes in Primary Care

    ERIC Educational Resources Information Center

    Duran, Bonnie; Oetzel, John; Parker, Tassy; Malcoe, Lorraine Halinka; Lucero, Julie; Jiang, Yizhou

    2009-01-01

    The relationship of intimate partner violence (IPV) with mental disorders was investigated among 234 American Indian/Alaska Native female primary care patients. Results indicated that unadjusted prevalence ratios for severe physical or sexual abuse (relative to no IPV) were significant for anxiety, PTSD, mood, and any mental disorder. Adjusted…

  17. Water developments and canids in two North American deserts: a test of the indirect effect of water hypothesis.

    PubMed

    Hall, Lucas K; Larsen, Randy T; Knight, Robert N; Bunnell, Kevin D; McMillan, Brock R

    2013-01-01

    Anthropogenic modifications to landscapes intended to benefit wildlife may negatively influence wildlife communities. Anthropogenic provisioning of free water (water developments) to enhance abundance and distribution of wildlife is a common management practice in arid regions where water is limiting. Despite the long-term and widespread use of water developments, little is known about how they influence native species. Water developments may negatively influence arid-adapted species (e.g., kit fox, Vulpes macrotis) by enabling water-dependent competitors (e.g., coyote, Canis latrans) to expand distribution in arid landscapes (i.e., indirect effect of water hypothesis). We tested the two predictions of the indirect effect of water hypothesis (i.e., coyotes will visit areas with free water more frequently and kit foxes will spatially and temporally avoid coyotes) and evaluated relative use of free water by canids in the Great Basin and Mojave Deserts from 2010 to 2012. We established scent stations in areas with (wet) and without (dry) free water and monitored visitation by canids to these sites and visitation to water sources using infrared-triggered cameras. There was no difference in the proportions of visits to scent stations in wet or dry areas by coyotes or kit foxes at either study area. We did not detect spatial (no negative correlation between visits to scent stations) or temporal (no difference between times when stations were visited) segregation between coyotes and kit foxes. Visitation to water sources was not different for coyotes between study areas, but kit foxes visited water sources more in Mojave than Great Basin. Our results did not support the indirect effect of water hypothesis in the Great Basin or Mojave Deserts for these two canids.

  18. Water Developments and Canids in Two North American Deserts: A Test of the Indirect Effect of Water Hypothesis

    PubMed Central

    Hall, Lucas K.; Larsen, Randy T.; Knight, Robert N.; Bunnell, Kevin D.; McMillan, Brock R.

    2013-01-01

    Anthropogenic modifications to landscapes intended to benefit wildlife may negatively influence wildlife communities. Anthropogenic provisioning of free water (water developments) to enhance abundance and distribution of wildlife is a common management practice in arid regions where water is limiting. Despite the long-term and widespread use of water developments, little is known about how they influence native species. Water developments may negatively influence arid-adapted species (e.g., kit fox, Vulpes macrotis) by enabling water-dependent competitors (e.g., coyote, Canis latrans) to expand distribution in arid landscapes (i.e., indirect effect of water hypothesis). We tested the two predictions of the indirect effect of water hypothesis (i.e., coyotes will visit areas with free water more frequently and kit foxes will spatially and temporally avoid coyotes) and evaluated relative use of free water by canids in the Great Basin and Mojave Deserts from 2010 to 2012. We established scent stations in areas with (wet) and without (dry) free water and monitored visitation by canids to these sites and visitation to water sources using infrared-triggered cameras. There was no difference in the proportions of visits to scent stations in wet or dry areas by coyotes or kit foxes at either study area. We did not detect spatial (no negative correlation between visits to scent stations) or temporal (no difference between times when stations were visited) segregation between coyotes and kit foxes. Visitation to water sources was not different for coyotes between study areas, but kit foxes visited water sources more in Mojave than Great Basin. Our results did not support the indirect effect of water hypothesis in the Great Basin or Mojave Deserts for these two canids. PMID:23844097

  19. Desert salt flats as oases for the spider Saltonia incerta Banks (Araneae: Dictynidae).

    PubMed

    Crews, Sarah C; Gillespie, Rosemary G

    2014-10-01

    The deserts of southwestern North America have undergone dramatic changes over their recent geological history including large changes in size and connectivity during the Pleistocene glaciopluvial cycles. This study examines the population history of the rare spider Saltonia incerta, once thought to be extinct, to determine the role of past climatological events in shaping the structure of the species. This species is restricted to salt crusts of intermittent or dry lakes, streams or rivers in the desert southwest, a region that was much wetter during glacial periods. We examine the distribution and genetic variability of populations to test whether there is recent dispersal throughout the range of the species. Analyses of mitochondrial and nuclear DNA indicate significant population structure, with one major clade comprising New Mexico localities and one comprising California-northern Baja California localities. Finer-scale structure is evident within the California clade, although not all of the subclades are reciprocally monophyletic. However, isolation with migration analysis suggests that migration is very low to non-existent. These results extend the known distribution of Saltonia, provide genetic evidence of strong isolation among localities within drainage basins and between drainage basins and provide a mechanistic understanding of population connectivity after the aridification of the American southwest. The implication is that although the species' distribution has been fragmented, populations have persisted throughout this area, suggesting that desert salt flats may have served as refugia for at least some terrestrial species.

  20. Desert salt flats as oases for the spider Saltonia incerta Banks (Araneae: Dictynidae).

    PubMed

    Crews, Sarah C; Gillespie, Rosemary G

    2014-10-01

    The deserts of southwestern North America have undergone dramatic changes over their recent geological history including large changes in size and connectivity during the Pleistocene glaciopluvial cycles. This study examines the population history of the rare spider Saltonia incerta, once thought to be extinct, to determine the role of past climatological events in shaping the structure of the species. This species is restricted to salt crusts of intermittent or dry lakes, streams or rivers in the desert southwest, a region that was much wetter during glacial periods. We examine the distribution and genetic variability of populations to test whether there is recent dispersal throughout the range of the species. Analyses of mitochondrial and nuclear DNA indicate significant population structure, with one major clade comprising New Mexico localities and one comprising California-northern Baja California localities. Finer-scale structure is evident within the California clade, although not all of the subclades are reciprocally monophyletic. However, isolation with migration analysis suggests that migration is very low to non-existent. These results extend the known distribution of Saltonia, provide genetic evidence of strong isolation among localities within drainage basins and between drainage basins and provide a mechanistic understanding of population connectivity after the aridification of the American southwest. The implication is that although the species' distribution has been fragmented, populations have persisted throughout this area, suggesting that desert salt flats may have served as refugia for at least some terrestrial species. PMID:25614800

  1. Desert salt flats as oases for the spider Saltonia incerta Banks (Araneae: Dictynidae)

    PubMed Central

    Crews, Sarah C; Gillespie, Rosemary G

    2014-01-01

    The deserts of southwestern North America have undergone dramatic changes over their recent geological history including large changes in size and connectivity during the Pleistocene glaciopluvial cycles. This study examines the population history of the rare spider Saltonia incerta, once thought to be extinct, to determine the role of past climatological events in shaping the structure of the species. This species is restricted to salt crusts of intermittent or dry lakes, streams or rivers in the desert southwest, a region that was much wetter during glacial periods. We examine the distribution and genetic variability of populations to test whether there is recent dispersal throughout the range of the species. Analyses of mitochondrial and nuclear DNA indicate significant population structure, with one major clade comprising New Mexico localities and one comprising California-northern Baja California localities. Finer-scale structure is evident within the California clade, although not all of the subclades are reciprocally monophyletic. However, isolation with migration analysis suggests that migration is very low to non-existent. These results extend the known distribution of Saltonia, provide genetic evidence of strong isolation among localities within drainage basins and between drainage basins and provide a mechanistic understanding of population connectivity after the aridification of the American southwest. The implication is that although the species' distribution has been fragmented, populations have persisted throughout this area, suggesting that desert salt flats may have served as refugia for at least some terrestrial species. PMID:25614800

  2. Some thoughts on the factors that controlled prehistoric maize production in the American Southwest with application to southwestern Colorado

    USGS Publications Warehouse

    Benson, L.V.; Ramsey, D.K.; Stahle, D.W.; Petersen, K.L.

    2013-01-01

    In this paper, we present a model of prehistoric southwestern Colorado maize productivity. The model is based on a tree-ring reconstruction of water-year precipitation for Mesa Verde for the period A.D. 480 to 2011. Correlation of historic Mesa Verde precipitation with historic precipitation at 11 other weather stations enabled the construction of an elevation-dependent precipitation function. Prehistoric water-year precipitation values for Mesa Verde together with the elevation-dependent precipitation function allowed construction of the elevation of southwest Colorado precipitation contours for each year since A.D. 480, including the 30-cm contour, which represents the minimum amount of precipitation necessary for the production of maize and the 50-cm contour, which represents the optimum amount of precipitation necessary for the production of maize. In this paper, calculations of prehistoric maize productivity and field life for any specific elevation are also demonstrated. These calculations were performed using organic nitrogen measurements made on seven southwestern Colorado soil groups together with values of reconstructed water-year precipitation and estimations of the organic nitrogen mineralization rate.

  3. 29. ISLAND PLANT: INTERIOR VIEW LOOKING SOUTHWEST ON GROUND FLOOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. ISLAND PLANT: INTERIOR VIEW LOOKING SOUTHWEST ON GROUND FLOOR - American Falls Water, Power & Light Company, Island Power Plant, Snake River, below American Falls Dam, American Falls, Power County, ID

  4. Chronology, sedimentology, and microfauna of groundwater discharge deposits in the central Mojave Desert, Valley Wells, California

    USGS Publications Warehouse

    Pigati, Jeffrey S.; Miller, David M.; Bright, Jordon E.; Mahan, Shannon; Nekola, Jeffrey C.; Paces, James B.

    2011-01-01

    During the late Pleistocene, emergent groundwater supported persistent and long-lived desert wetlands in many broad valleys and basins in the American Southwest. When active, these systems provided important food and water sources for local fauna, supported hydrophilic and phreatophytic vegetation, and acted as catchments for eolian and alluvial sediments. Desert wetlands are represented in the geologic record by groundwater discharge deposits, which are also called spring or wetland deposits. Groundwater discharge deposits contain information on the timing and magnitude of past changes in water-table levels and, thus, are a source of paleohydrologic and paleoclimatic information. Here, we present the results of an investigation of extensive groundwater discharge deposits in the central Mojave Desert at Valley Wells, California. We used geologic mapping and stratigraphic relations to identify two distinct wetland sequences at Valley Wells, which we dated using radiocarbon, luminescence, and uranium-series techniques. We also analyzed the sediments and microfauna (ostracodes and gastropods) to reconstruct the specific environments in which they formed. Our results suggest that the earliest episode of high water-table conditions at Valley Wells began ca. 60 ka (thousands of calendar yr B.P.), and culminated in peak discharge between ca. 40 and 35 ka. During this time, cold (4–12 °C) emergent groundwater supported extensive wetlands that likely were composed of a wet, sedge-rush-tussock meadow mixed with mesic riparian forest. After ca. 35 ka, the water table dropped below the ground surface but was still shallow enough to support dense stands of phreatophytes through the Last Glacial Maximum (LGM). The water table dropped further after the LGM, and xeric conditions prevailed until modest wetlands returned briefly during the Younger Dryas cold event (13.0–11.6 ka). We did not observe any evidence of wet conditions during the Holocene at Valley Wells. The timing

  5. Chronology, sedimentology, and microfauna of groundwater discharge deposits in the central Mojave Desert, Valley Wells, California

    USGS Publications Warehouse

    Pigati, J.S.; Miller, D.M.; Bright, J.E.; Mahan, S.A.; Nekola, J.C.; Paces, J.B.

    2011-01-01

    groundwater supported persistent and long-lived desert wetlands in many broad valleys and basins in the American Southwest. When active, these systems provided important food and water sources for local fauna, supported hydrophilic and phreatophytic vegetation, and acted as catchments for eolian and alluvial sediments. Desert wetlands are represented in the geologic record by groundwater discharge deposits, which are also called spring or wetland deposits. Groundwater discharge deposits contain information on the timing and magnitude of past changes in water-table levels and, thus, are a source of paleohydrologic and paleoclimatic information. Here, we present the results of an investigation of extensive groundwater discharge deposits in the central Mojave Desert at Valley Wells, California. We used geologic mapping and stratigraphic relations to identify two distinct wetland sequences at Valley Wells, which we dated using radiocarbon, luminescence, and uranium-series techniques. We also analyzed the sediments and microfauna (ostracodes and gastropods) to reconstruct the specific environments in which they formed. Our results suggest that the earliest episode of high water-table conditions at Valley Wells began ca. 60 ka (thousands of calendar yr B.P.), and culminated in peak discharge between ca. 40 and 35 ka. During this time, cold (4-12 ??C) emergent groundwater supported extensive wetlands that likely were composed of a wet, sedge-rush-tussock meadow mixed with mesic riparian forest. After ca. 35 ka, the water table dropped below the ground surface but was still shallow enough to support dense stands of phreatophytes through the Last Glacial Maximum (LGM). The water table dropped further after the LGM, and xeric conditions prevailed until modest wetlands returned briefly during the Younger Dryas cold event (13.0-11.6 ka). We did not observe any evidence of wet conditions during the Holocene at Valley Wells. The timing of these fluctuations is consistent with

  6. Thar Desert

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This ASTER sub-scene covers an area of 12 x 15 km in NW India in the Thar Desert. The sand dunes of the Thar Desert constantly shift and take on new shapes. Located in northwestern India and eastern Pakistan, the desert is bounded on the south by a salt marsh known as the Rann of Kutch, and on the west by the Indus River plain. About 800 kilometers long and about 490 kilometers wide, the desert's terrain is mainly rolling sandhills with scattered growths of shrub and rock outcroppings. Only about 12 to 25 centimeters of rain fall on the desert each year, and temperatures rise as high as 52 degrees Celsius. Much of the population is pastoral, raising sheep for their wool. The image is located at 24.4 degrees north latitude and 69.3 degrees east longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  7. Desert Scrublands

    USGS Publications Warehouse

    Jones, L.L.C.; Halama, K.J.; Lovich, R.E.

    2016-01-01

    Desert scrublands comprise the lower to mid-elevation portions of four different ecosystems including the Chihuahuan, Great Basin, Mojave and Sonoran Deserts. Together the area inside their outer boundaries includes over 8% of the surface area of the United States. Despite significant differences in the flora and fauna of these bioregions they all share the common trait of being arid shrub-steppe ecosystems, receiving, on average, less than 254 mm of rain per year. The austere nature of these landscapes belies their significant biodiversity, the amazing behavioral and physiological adaptations of the biota, and the fragility of the ecosystems to human disturbances. For example, the Mojave Desert alone has at least 250 species of ephemeral plants, mostly winter annuals, and up to 90% are endemic.

  8. Climate change and its impact on precipitation, runoff, and erosion in a small semi-arid watershed of the American Southwest

    NASA Astrophysics Data System (ADS)

    Lu, Meng; Renschler, Chris; Nearing, Mark

    2014-05-01

    Changes in precipitation due to climate change may contribute to changes of soil erosion and runoff in semi-arid rangelands. Therefore it is important to quantify the spatial-temporal characteristics of precipitation in order to better understand climate impacts on soil erosion and sedimentation. This study investigates historic changes in spatial-temporal precipitation and the responses of corresponding soil erosion and sedimentation in a small catchment of the Walnut Gulch Experimental Watershed (WGEW) - a semiarid rangeland watershed of the American Southwest. Spatial and temporal dynamics in rainfall and rainfall energy and erosivity are analyzed on the more than 50 years of records in the densely distributed rainfall gauges network in WGEW. The discussion focuses on data preprocessing, time series modeling, dimension reduction, spatial-temporal analysis, and potentially the spatial-temporal array in data management. The process-based hydrological and soil erosion model -Water Erosion Prediction Project (WEPP) (Flanagan and Nearing, 1995) and the GIS interface of WEPP - GeoWEPP (Renschler, 2003) was used to investigate the relationship between climate change and soil erosion. Observed precipitation and precipitation statistics that represent the watershed were processed into climate files and applied to simulate the runoff, sediment yield and erosion with WEPP/GeoWEPP in hillslope and different watershed scales, of which the results were compared with annual rainfall erosivity. The contributions of this study were: 1) analyzing the explicit spatial-temporal rainfall and rainfall energy; 2) testing the capability of WEPP/GeoWEPP in simulating climate change effects on sediment leaving and soil erosion in semiarid rangeland watersheds; and 3) analyzing the impact of climate change on water runoff and soil erosion.

  9. Interactions of landscape position, stream flow, and litter quality on litter decomposition in intermittent to ephemeral streams in the American Southwest

    NASA Astrophysics Data System (ADS)

    Lohse, K. A.; Schwabedissen, S. G.; Gallo, E. L.; Meixner, T.

    2014-12-01

    Ephemeral streams are an important but little studied resource in the American Southwest. Many streams in arid and semi-arid regions are ephemeral (e.g. 89% of western US), only flowing in response to rainfall, and the distribution of these streams is likely to increase in a changing climate. Given the hydrologic variability and additional water present in ephemeral stream systems, decomposition rates are likely to vary as a function of stream flow presence and soil-water presence. Here we examine how different types of litter decompose across a climate gradient in Arizona with a range of ephemeral, intermittent to perennial streams. We used a space for time substitution and deployed common gamble oak and sycamore litterbags at three replicate reach transects at 13 sites in Arizona over an 18-month period. Within each of these sites, we deployed little bags in channel, riparian, and channel landscape positions for (1100 total litter bags). We measured soil-water presence and stream flow days with electrical resistivity sensors. Cumulative rainfall ranged from 9 to 38 cm across the sites whereas cumulative stream flow presence varied dramatically across the sites, from 11 to 433 days over the 18-month deployment. As expected, rates of decomposition were higher in channels than riparian and upland positions at sites with higher soil-water and stream flow presence and slower for oak compared to sycamore leaves. Eighty-six of the oak compared to seventy four percent of the sycamore mass was remaining after 180 days. Cumulative days of soil -water presence and stream flow associated with each site were positively related to rates of decomposition of litter located in channels suggesting that changes in streamflow and soil-water presence associated climate change will have large effects of rates of nutrient release via the process of decomposition.

  10. Evaluating Changes in Extreme Weather During the North American Monsoon in the Southwest U.S. Using High Resolution, Convective-Permitting Regional Atmospheric Modeling

    NASA Astrophysics Data System (ADS)

    Castro, C. L.; Chang, H. I.; Luong, T. M.; Lahmers, T.; Jares, M.; Mazon, J.; Carrillo, C. M.; Adams, D. K.

    2015-12-01

    The North American monsoon (NAM) is the principal driver of summer severe weather in the Southwest U.S. Monsoon convection typically initiates during daytime over the mountains and may organize into mesoscale convective systems (MCSs). Most monsoon-related severe weather occurs in association with organized convection, including microbursts, dust storms, flash flooding and lightning. A convective resolving grid spacing (on the kilometer scale) model is required to explicitly represent the physical characteristics of organized convection, for example the presence of leading convective lines and trailing stratiform precipitation regions. Our objective is to analyze how monsoon severe weather is changing in relation to anthropogenic climate change. We first consider a dynamically downscaled reanalysis during a historical period 1948-2010. Individual severe weather event days, identified by favorable thermodynamic conditions, are then simulated for short-term, numerical weather prediction-type simulations of 30h at a convective-permitting scale. Changes in modeled severe weather events indicate increases in precipitation intensity in association with long-term increases in atmospheric instability and moisture, particularly with organized convection downwind of mountain ranges. However, because the frequency of synoptic transients is decreasing during the monsoon, organized convection is less frequent and convective precipitation tends to be more phased locked to terrain. These types of modeled changes also similarly appear in observed CPC precipitation, when the severe weather event days are selected using historical radiosonde data. Next, we apply the identical model simulation and analysis procedures to several dynamically downscaled CMIP3 and CMIP5 models for the period 1950-2100, to assess how monsoon severe weather may change in the future with respect to occurrence and intensity and if these changes correspond with what is already occurring in the historical

  11. Desert Survivors!

    ERIC Educational Resources Information Center

    Horton, Jessica; Friedenstab, Steve

    2013-01-01

    This article describes a special third-grade classroom unit based on the reality show "Survivor." The goal of this engaging and interactive unit was to teach students about physical and behavioral adaptations that help animals survive in various desert biomes. The activity combines research, argument, and puppet play over one week of…

  12. Discovering Deserts.

    ERIC Educational Resources Information Center

    Braus, Judy, Ed.

    1985-01-01

    Ranger Rick's NatureScope is a creative education series dedicated to inspiring in children an understanding and appreciation of the natural world while developing the skills they will need to make responsible decisions about the environment. The topic of this issue is "Discovering Deserts." Contents are organized into the following sections: (1)…

  13. Desert and desertification in Iran

    NASA Astrophysics Data System (ADS)

    Bahrami, M.

    2009-04-01

    One of the greatest environmental concerns in Iran as in other arid and semiarid countries is the transformation of once productive, or marginally productive, land to deteriorated land and soil unable to support plants and animals. Because the land becomes barren and dry, the process is described as desertification, which occurs as a sequence of events. The area of deserts in Iran is about 340,000 Km2 (less than one fifth of its total area), of which 100,000 Km2 is being used for some cultivation, 120,000 Km2 is subjected to moving sands about 40 % of which is active sand dunes. Most of features and processes usual in world famous deserts are also observed in Iran: low precipitation, high evaporation, poor or lack of vegetation, saline and alkaline soils, low population and small and sparse oases. The deserts of Iran are generally classified in the subtropical, warm, arid and semiarid group, but the effect and presence of some geographical and geoclimatical factors such as height, vicinity to Indian Ocean and so on do some changes in climatic conditions and geographical features causing some local and regional differences in them. Geographically, two groups of deserts have been known in Iran: (1) Coastal deserts which, like a ribbon with variable width, stretch from extreme southeast to extreme southwest, at the north parts of Oman Sea and Persian Gulf. One important feature of these deserts is relatively high humidity which differentiates them from other deserts. This causes an increase in vegetation coverage and hence a decrease in eolian erosion and also a dominance of chemical weathering to that of physical. (2) internal deserts, which rest in central, eastern and southeastern plateau of the country and in independent and semi dependent depressions. This situation, which is due to the surrounding high mountains, blocks humidity entry and causes the aridity of these deserts. Wind as a dominant process in the area causes deflated features such as Reg (desert

  14. View to the northeast of the southwest elevation OvertheHorizon ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View to the northeast of the southwest elevation - Over-the-Horizon Backscatter Radar Network, Mountain Home Air Force Operations Building, On Desert Street at 9th Avenue Mountain Home Air Force Base, Mountain Home, Elmore County, ID

  15. Detectable Aspects Of Alaska, and the Southwests Kokopelli, Indicate That Environmental Monitoring By Native Americans Utilized Several Sensory Modes, and That Their Conservation Held Moral Value Within Their Traditional Culture.

    NASA Astrophysics Data System (ADS)

    Ochs, Michael Ann; Mc Leod, Roger D.

    2004-03-01

    Place-names of Alaska and the Americas, in names like Natick, MA, Matagamon, ME, Matacumbe Key, FL, Tecate Mt, CA, and Tacoma, WA as well as Allapatah, FL, and Issaqua, WA indicate Native Americans all monitored equivalent aspects of the earths EMF. Former coastal and island areas of Native American activity and culture in Alaska show a traditional, historic leader climbed the mountain of one cliff-like island area for weather prediction. We suggest that the ascent onto the mountain and the subsequent significant stay there was for purposes of cultural and religious reverence associated with direct observation of phenomena associated with known weather sequences. Similar cultural awareness of EMF phenomena and weather-making could be related to practices of the MiKmaw/Micmac Indians of the northeast, and the so-called rain-dance of the Hopi of the southwest. *This paper does not necessarily represent the views of the U.S. E.P.A

  16. Detectable Aspects Of Alaska, and the Southwests Kokopelli, Indicate That Environmental Monitoring By Native Americans Utilized Several Sensory Modes, and That Their Conservation Held Moral Value Within Their Traditional Culture.

    NASA Astrophysics Data System (ADS)

    Ochs, Michael Ann; Mc Leod, Roger D.

    2004-03-01

    Place-names of Alaska and the Americas, in names like Natick, MA, Matagamon, ME, Matacumbe Key, FL, Tecate Mt, CA, and Tacoma, WA as well as Allapatah, FL, and Issaqua, WA indicate Native Americans all monitored equivalent aspects of the earths EMF. Former coastal and island areas of Native American activity and culture in Alaska show a traditional, historic leader climbed the mountain of one cliff-like island area for weather prediction. We suggest that the ascent onto the mountain and the subsequent significant stay there was for purposes of cultural and religious reverence associated with direct observation of phenomena associated with known weather sequences. Similar cultural awareness of EMF phenomena and weather-making could be related to practices of the MiKmaw/Micmac Indians of the northeast, and the so-called rain-dance of the Hopi of the southwest. *This paper does not necessarily represent the views of the U.S. E.P.A

  17. Cryptic Neogene vicariance and Quaternary dispersal of the red-spotted toad (Bufo punctatus): insights on the evolution of North American warm desert biotas.

    PubMed

    Jaeger, Jef R; Riddle, Brett R; Bradford, David F

    2005-09-01

    We define the geographical distributions of mitochondrial DNA (mtDNA) lineages embedded within a broadly distributed, arid-dwelling toad, Bufo punctatus. These patterns were evaluated as they relate to hypothesized vicariant events leading to the formation of desert biotas within western North America. We assessed mtDNA sequence variation among 191 samples from 82 sites located throughout much of the species' range. Parsimony-based haplotype networks of major identified lineages were used in nested clade analysis (NCA) to further elucidate and evaluate shallow phylogeographic patterns potentially associated with Quaternary (Pleistocene-Holocene) vicariance and dispersal. Phylogenetic analyses provided strong support for three monophyletic lineages (clades) within B. punctatus. The geographical distributions of the clades showed little overlap and corresponded to the general boundaries of the Peninsular Desert, and two continental desert regions, Eastern (Chihuahuan Desert-Colorado Plateau) and Western (Mojave-Sonoran deserts), geographically separated along the Rocky Mountains and Sierra Madre Occidental. The observed divergence levels and congruence with postulated events in earth history implicate a late Neogene (latest Miocene-early Pliocene) time frame for separation of the major mtDNA lineages. Evaluation of nucleotide and haplotype diversity and interpretations from NCA reveal that populations on the Colorado Plateau resulted from a recent, likely post-Pleistocene, range expansion from the Chihuahuan Desert. Dispersal across historical barriers separating major continental clades appear to be recent, resulting in secondary contacts in at least two areas. Given the observed contact between major clades, we speculated as to why the observed deep phylogeographic structure has not been eroded during the multiple previous interglacials of the Pleistocene. PMID:16101772

  18. What Makes a Desert a Desert?

    ERIC Educational Resources Information Center

    NatureScope, 1985

    1985-01-01

    Presents background information and activities which focus on definition of a desert, locations of deserts, and factors influencing locations. Activities include objective(s), recommended age level(s), subject area(s), list of materials needed, and procedures. Two ready-to-copy pages with desert landforms and temperature/rainfall data are…

  19. Simulated distribution of an invasive grass, Lehmann lovegrass, in the Chihuahuan Desert under future climate scenarios

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background/Question/Methods Lehmann lovegrass (Eragrostis lehmanniana), a perennial grass introduced to the Southwest US in the 1930s from South Africa, has had a limited distribution in the Chihuahuan Desert while it has dominated many grassland sites in the Sonoran Desert.  Previous observational ...

  20. Mapping perennial vegetation cover in the Mojave Desert

    USGS Publications Warehouse

    Wallace, Cynthia S.A.

    2011-01-01

    Scientists with the U.S. Geological Survey's Western Geographic Science Center have recently created a regional map of perennial vegetation cover for the Mojave Desert. The scientists used existing field data collected for a variety of previous studies and satellite data available for free through USGS archives to create a calibrated model of percent vegetation cover, an important attribute of desert ecosystems. This map is being used to inform ongoing scientific investigations and land-management efforts, including endangered species habitat mapping and vulnerability and recoverability studies of desert landscapes in the arid Southwest.

  1. Evidence for high taxonomic and morphologic tyrannosauroid diversity in the Late Cretaceous (Late Campanian) of the American Southwest and a new short-skulled tyrannosaurid from the Kaiparowits formation of Utah

    NASA Astrophysics Data System (ADS)

    Carr, Thomas D.; Williamson, Thomas E.; Britt, Brooks B.; Stadtman, Ken

    2011-03-01

    The fossil record of late Campanian tyrannosauroids of western North America has a geographic gap between the Northern Rocky Mountain Region (Montana, Alberta) and the Southwest (New Mexico, Utah). Until recently, diagnostic tyrannosauroids from the Southwest were unknown until the discovery of Bistahieversor sealeyi from the late Campanian of New Mexico. Here we describe an incomplete skull and postcranial skeleton of an unusual tyrannosaurid from the Kaiparowits Formation (Late Cretaceous) of Utah that represents a new genus and species, Teratophoneus curriei. Teratophoneus differs from other tyrannosauroids in having a short skull, as indicated by a short and steep maxilla, abrupt angle in the postorbital process of the jugal, laterally oriented paroccipital processes, short basicranium, and reduced number of teeth. Teratophoneus is the sister taxon of the Daspletosaurus + Tyrannosaurus clade and it is the most basal North American tyrannosaurine. The presence of Teratophoneus suggests that dinosaur faunas were regionally endemic in the west during the upper Campanian. The divergence in skull form seen in tyrannosaurines indicates that the skull in this clade had a wide range of adaptive morphotypes.

  2. Evidence for high taxonomic and morphologic tyrannosauroid diversity in the Late Cretaceous (late Campanian) of the American Southwest and a new short-skulled tyrannosaurid from the Kaiparowits Formation of Utah.

    PubMed

    Carr, Thomas D; Williamson, Thomas E; Britt, Brooks B; Stadtman, Ken

    2011-03-01

    The fossil record of late Campanian tyrannosauroids of western North America has a geographic gap between the Northern Rocky Mountain Region (Montana, Alberta) and the Southwest (New Mexico, Utah). Until recently, diagnostic tyrannosauroids from the Southwest were unknown until the discovery of Bistahieversor sealeyi from the late Campanian of New Mexico. Here we describe an incomplete skull and postcranial skeleton of an unusual tyrannosaurid from the Kaiparowits Formation (Late Cretaceous) of Utah that represents a new genus and species, Teratophoneus curriei. Teratophoneus differs from other tyrannosauroids in having a short skull, as indicated by a short and steep maxilla, abrupt angle in the postorbital process of the jugal, laterally oriented paroccipital processes, short basicranium, and reduced number of teeth. Teratophoneus is the sister taxon of the Daspletosaurus + Tyrannosaurus clade and it is the most basal North American tyrannosaurine. The presence of Teratophoneus suggests that dinosaur faunas were regionally endemic in the west during the upper Campanian. The divergence in skull form seen in tyrannosaurines indicates that the skull in this clade had a wide range of adaptive morphotypes.

  3. Desert Bloom

    ERIC Educational Resources Information Center

    Krieger, Zvika

    2008-01-01

    With more than a dozen American universities opening branches and campuses on the Persian Gulf, the oil-rich emirates of the Arabian peninsula are threatening to dethrone cities like Cairo, Baghdad, and Beirut as the academic centers of the Middle East. Wealthy, safe, and relatively stable, these emirates are vying to become the new intellectual…

  4. Desert Voices: Southwestern Children's Literature.

    ERIC Educational Resources Information Center

    Polette, Keith

    1997-01-01

    Examines three books with different ways of writing about the desert. Discusses: "Here Is the Southwestern Desert" by Madeline Dunphy, "The Desert Is My Mother" by Pat Mora, and "The Desert Mermaid" by Alberto Blanco. (PA)

  5. Rock Art of the Greater Southwest

    NASA Astrophysics Data System (ADS)

    Krupp, Edwin C.

    Archaeoastronomical studies in the American Southwest began in 1955 with recognition of what seemed to be pictorial eyewitness records of the Crab supernova of 1054 AD In time, reports of seasonally significant light-and-shadow effects on rock art and associations of rock art with astronomical alignments also emerged. Most astronomical rock art studies remained problematic, however, because criteria for proof of ancient intent were elusive. Disciplined methods for assessing cultural function were difficult to develop, but review of ethnographically documented astronomical traditions of California Indians and of Indians in the American Southwest subsequently increased confidence in the value of some astronomical rock art initiatives.

  6. 75 FR 42119 - Notice of Intent to Repatriate Cultural Items: High Desert Museum, Bend, OR

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-20

    ... National Park Service Notice of Intent to Repatriate Cultural Items: High Desert Museum, Bend, OR AGENCY... cultural items in the possession of the High Desert Museum, Bend, OR, that meet the definition of... notice. In 1990, Native American cultural items were donated to the High Desert Museum by the Roger...

  7. Studies in Southwest Spanish.

    ERIC Educational Resources Information Center

    Bowen, J. Donald, Ed.; Ornstein, Jacob, Ed.

    The Spanish dialects of the Southwest United States have received little serious attention until recently. The present volume contains studies designed to contribute to the understanding and acceptance of Southwest Spanish. The book consists of the following chapters: (1) "Linguistic Diversity in Southwest Spanish," by Garland D. Bills and Jacob…

  8. Late Quaternary history of the Atacama Desert

    USGS Publications Warehouse

    Latorre, Claudio; Betancourt, Julio L.; Rech, Jason A.; Quade, Jay; Holmgren, Camille; Placzek, Christa; Maldonado, Antonio; Vuille, Mathias; Rylander, Kate A.; Smith, Mike; Hesse, Paul

    2005-01-01

    Of the major subtropical deserts found in the Southern Hemisphere, the Atacama Desert is the driest. Throughout the Quaternary, the most pervasive climatic influence on the desert has been millennial-scale changes in the frequency and seasonality of the scant rainfall, and associated shifts in plant and animal distributions with elevation along the eastern margin of the desert. Over the past six years, we have mapped modern vegetation gradients and developed a number of palaeoenvironmental records, including vegetation histories from fossil rodent middens, groundwater levels from wetland (spring) deposits, and lake levels from shoreline evidence, along a 1200-kilometre transect (16–26°S) in the Atacama Desert. A strength of this palaeoclimate transect has been the ability to apply the same methodologies across broad elevational, latitudinal, climatic, vegetation and hydrological gradients. We are using this transect to reconstruct the histories of key components of the South American tropical (summer) and extratropical (winter) rainfall belts, precisely at those elevations where average annual rainfall wanes to zero. The focus has been on the transition from sparse, shrubby vegetation (known as the prepuna) into absolute desert, an expansive hyperarid terrain that extends from just above the coastal fog zone (approximately 800 metres) to more than 3500 metres in the most arid sectors in the southern Atacama.

  9. Palynological evidence for the historic expansion of juniper and desert shrubs in Arizona, U.S.A.

    USGS Publications Warehouse

    Davis, O.K.; Turner, R.M.

    1986-01-01

    Analysis of the sediment of Pecks Lake, Yavapai County, Arizona, has permitted the first reported palynological evidence for the historic expansion of juniper and desert shrubs in the American Southwest. The palynological evidence is supported by the comparison of modern and historical photographs, which shows the regional expansion of pinyon-juniper woodland, and the local increase of mesquite and creosote bush. A gradual increase in juniper pollen percentages began over 2000 years ago, but the rate of increase abruptly accelerated after the historic introduction of grazing animals. In contrast, juniper percentages did not increase during a prehistoric interval of intense disturbance by humans, about A.D. 1200, and a different weed flora was present. Prehistorically, water depth was greatest at ca. 600 B.C. and was lowest just prior to the arrival of Europeans. Regional climate has gradually cooled since the beginning of the record at 2630 B.P. ?? 1986.

  10. Strategies to Resist Drug Offers Among Urban American Indian Youth of the Southwest: An Enumeration, Classification, and Analysis by Substance and Offeror

    PubMed Central

    Kulis, Stephen; Reeves, Leslie Jumper; Dustman, Patricia Allen; O’Neill, Marissa

    2011-01-01

    This study explores the drug resistance strategies of urban American Indian adolescents when they encounter people offering them alcohol, cigarettes, and marijuana. Data were collected in 2005 from 11 female and 9 male adolescents who self-identified as American Indian and attended two urban middle schools in the southwestern United States. In two focus groups—one at each school site—the youth described their reactions to 25 hypothetical substance offer scenarios drawn from real-life narratives of similar youth. Qualitative analysis of their 552 responses to the scenarios generated 14 categories. Half of the responses were strategies reported most often by nonnative youth (refuse, explain, leave, and avoid). Using ecodevelopmental theory, the responses were analyzed for indications of culturally specific ways of resisting substance offers, such as variation by specific substance and relationship to the person offering. Study limitations are noted along with suggestive implications for future research on culturally appropriate prevention approaches for urban American Indian youth. PMID:21810074

  11. History, Heritage, and Hearsay: A Children's Guide to Ethnic South and Southwest Philadelphia.

    ERIC Educational Resources Information Center

    D'Amico, Joseph J.; Newcombe, Ellen

    This guide for elementary students will help them learn about five of South and Southwest Philadelphia's ethnic groups and examine their own ethnic heritage. These groups are: Afro Americans, Irish Americans, Italian Americans, Jewish Americans, and Polish Americans. The guide has different sections. "Hearsay" sections contain short stories based…

  12. Reconstructing Past Vegetation Types During the Late Holocene Using Stable Carbon Isotopes of Leporids from Archaeological Sites in the American Southwest

    NASA Astrophysics Data System (ADS)

    Mauldin, R. P.; Munoz, C.; Kemp, L.; Hard, R.

    2012-12-01

    Stable carbon isotopes (δ13C) from bone collagen in leporids provide high-resolution vegetation reconstruction. Leporids [e.g., cottontails (Sylvilagus sp.), jackrabbits (Lepus sp.)] die young (ca. 2 years) and use small home ranges (< 1 km2). They consume a variety of vegetation, including plants that use both C3 and C4/CAM photosynthetic pathways. Leporids appear to focus on new growth as it becomes available throughout the year, perhaps as a function of water content. Their diet, and their bone collagen, provides a high-resolution view of the carbon isotopic values present in their local plant community. Here we provide an example of the use of leporid bone collagen for reconstruction of past vegetation types using data from several archaeological sites as well as modern collections. All samples are from a basin and range setting within the Chihuahuan Desert in far west Texas and southern New Mexico, USA. The sites span a period back to roughly 1350 BP. Isotopic patterns in leporid collagen show clear evidence of change in vegetation from around 775 BP to the modern period, with a dramatic shift of 4.2‰ in median δ13C values over this period in jackrabbit collagen and a 7.3‰ decrease in median carbon isotopic values in cottontail rabbits. These data suggest a significant increase in C3 plants in leporid diet, and by extension a relative increase in these plant types in the local environment sampled by leporids. This shift is consistent with historic accounts of more C3 mesquite, possibly because of historic land use and ranching practices in the 1800s. However, while this shift may have been accelerated by historic land use changes, our data suggest that the vegetation shift began several hundred years earlier during the prehistoric period. The prehistoric collagen isotopic record also shows increased sample variability through time in both species, suggesting that year-to-year variability in vegetation may have increased late in that sequence. Our results

  13. American Indian Recipes.

    ERIC Educational Resources Information Center

    Gurnoe, Katherine J.; Skjervold, Christian, Ed.

    Presenting some 60 to 70 Native American recipes, this document includes a brief introduction and a suggested reading list (15 citations related to American Indian foods). The introduction identifies five regional Native American cuisines as follows: in the Southwest, peppers and beans were made into chili, soups, guacamole, and barbecue sauces by…

  14. Association of Common Genetic Variants with Diabetes and Metabolic Syndrome Related Traits in the Arizona Insulin Resistance Registry: A Focus on Mexican American Families in the Southwest

    PubMed Central

    DeMenna, Jacob; Puppala, Sobha; Chittoor, Geetha; Schneider, Jennifer; Kim, Joon Young; Shaibi, Gabriel Q.; Mandarino, Lawrence J.; Duggirala, Ravindranath; Coletta, Dawn K.

    2016-01-01

    Background/Aims The increased occurrence of type 2 diabetes and its clinical correlates is a global public health issue, and there are continued efforts to find its genetic determinant across ethnically diverse populations. The aims of this study were to determine the heritability of diabetes and metabolic syndrome phenotypes in the Arizona Insulin Resistance (AIR) registry and to perform an association analysis of common single nucleotide polymorphisms (SNPs) identified by GWAS with these traits. All study participants were Mexican Americans from the AIR registry. Methods Metabolic, anthropometric, demographic and medical history information was obtained on the 667 individuals enrolled in the registry. Results The heritability estimates were moderate to high in magnitude and significant, indicating that the AIR registry is well suited for the identification of genetic factors contributing to diabetes and the metabolic syndrome. From the 30 GWAS genes selected (some genes were represented by multiple SNPs), 20 SNPs exhibited associations with one or more of the diabetes related traits with nominal significance (p ≤ 0.05). In addition, 25 SNPs were nominally significantly associated with one or more of the metabolic phenotypes tested (p ≤ 0.05). Most notably, 5 SNPs from 5 genes [body mass index (BMI), hip circumference: rs3751812/FTO; fasting plasma glucose, hemoglobin A1c: rs4607517/GCK; very-low-density lipoprotein: rs10830963/MTNR1B; BMI: rs13266634/SLC30A8, and total cholesterol, low-density lipoprotein: rs7578597/THADA] were significantly associated with obesity, glycemic, and lipid phenotypes when using the multiple testing significance threshold of 0.0015. Conclusion These findings extend previous work on Mexican Americans to suggest that metabolic disease is strongly influenced by genetic background in this high-risk population. PMID:25060389

  15. Animals of the Desert.

    ERIC Educational Resources Information Center

    NatureScope, 1985

    1985-01-01

    Provides background information and student activities on how desert animals have adapted to dryness and heat, how and when animals move on the desert, and nocturnal/diurnal animals. Each activity includes objective(s), recommended age level(s), subject area(s), list of materials needed, and procedures. Ready-to-copy pages are included for a…

  16. Mapping habitat for multiple species in the Desert Southwest

    USGS Publications Warehouse

    Inman, Richard D.; Nussear, Kenneth E.; Esque, Todd C.; Vandergast, Amy G.; Hathaway, Stacie A.; Wood, Dustin A.; Barr, Kelly R.; Fisher, Robert N.

    2014-01-01

    Many utility scale renewable energy projects are currently proposed across the Mojave Ecoregion. Agencies that manage biological resources throughout this region need to understand the potential impacts of these renewable energy projects and their associated infrastructure (for example, transmission corridors, substations, access roads, etc.) on species movement, genetic exchange among populations, and species’ abilities to adapt to changing environmental conditions. Understanding these factors will help managers’ select appropriate project sites and possibly mitigate for anticipated effects of management activities. We used species distribution models to map habitat for 15 species across the Mojave Ecoregion to aid regional land-use management planning. Models were developed using a common 1 × 1 kilometer resolution with maximum entropy and generalized additive models. Occurrence data were compiled from multiple sources, including VertNet (http://vertnet.org/), HerpNET (http://www.herpnet.org), and MaNIS (http://manisnet.org), as well as from internal U.S. Geological Survey databases and other biologists. Background data included 20 environmental covariates representing terrain, vegetation, and climate covariates. This report summarizes these environmental covariates and species distribution models used to predict habitat for the 15 species across the Mojave Ecoregion.

  17. Gobi Desert, China as seen from STS-59

    NASA Technical Reports Server (NTRS)

    1994-01-01

    View to the south by southwest across the southern Gobi Desert (China) across the Chi-Lien-Shan or Quilienshan or Nanshan (Mountains) in Gansu Province to Lake Quinghai or Ch'ing-Hai (orthography varies with political conditions and scholarship) in Quinghai Province. The lake has a surface elevation of 10,450 feet, partially filling one of the easternmost closed drainage basins of Central Asia.

  18. Making silica rock coatings in the lab: synthetic desert varnish

    NASA Astrophysics Data System (ADS)

    Perry, Randall S.; Kolb, Vera M.; Philip, Ajish I.; Lynne, Bridget Y.; McLoughlin, Nicola; Sephton, Mark; Wacey, David; Green, Owen R.

    2005-09-01

    Desert varnish and silica rock coatings have perplexed investigators since Humboldt and Darwin. They are found in arid regions and deserts on Earth but the mechanism of their formation remains challenging (see Perry et al. this volume). One method of researching this is to investigate natural coatings, but another way is to attempt to produce coatings in vitro. Sugars, amino acids, and silicic acid, as well as other organic and (bio)organic compounds add to the complexity of naturally forming rock coatings. In the lab we reduced the complexity of the natural components and produced hard, silica coatings on basaltic chips obtained from the Mojave Desert. Sodium silicate solution was poured over the rocks and continuously exposed to heat and/or UV light. Upon evaporation the solutions were replenished. Experiments were performed at various pH's. The micro-deposits formed were analyzed using optical, SEM-EDAX, and electron microprobe. The coatings formed are similar in hardness and composition to silica glazes found on basalts in Hawaii as well as natural desert varnish found in US southwest deserts. Thermodynamic mechanisms are presented showing the theoretical mechanisms for overcoming energy barriers that allow amorphous silica to condense into hard coatings. This is the first time synthetic silica glazes that resemble natural coatings in hardness and chemical composition have been successfully reproduced in the laboratory, and helps to support an inorganic mechanism of formation of desert varnish as well as manganese-deficient silica glazes.

  19. ABCC8 R1420H Loss-of-Function Variant in a Southwest American Indian Community: Association With Increased Birth Weight and Doubled Risk of Type 2 Diabetes.

    PubMed

    Baier, Leslie J; Muller, Yunhua Li; Remedi, Maria Sara; Traurig, Michael; Piaggi, Paolo; Wiessner, Gregory; Huang, Ke; Stacy, Alyssa; Kobes, Sayuko; Krakoff, Jonathan; Bennett, Peter H; Nelson, Robert G; Knowler, William C; Hanson, Robert L; Nichols, Colin G; Bogardus, Clifton

    2015-12-01

    Missense variants in KCNJ11 and ABCC8, which encode the KIR6.2 and SUR1 subunits of the β-cell KATP channel, have previously been implicated in type 2 diabetes, neonatal diabetes, and hyperinsulinemic hypoglycemia of infancy (HHI). To determine whether variation in these genes affects risk for type 2 diabetes or increased birth weight as a consequence of fetal hyperinsulinemia in Pima Indians, missense and common noncoding variants were analyzed in individuals living in the Gila River Indian Community. A R1420H variant in SUR1 (ABCC8) was identified in 3.3% of the population (N = 7,710). R1420H carriers had higher mean birth weights and a twofold increased risk for type 2 diabetes with a 7-year earlier onset age despite being leaner than noncarriers. One individual homozygous for R1420H was identified; retrospective review of his medical records was consistent with HHI and a diagnosis of diabetes at age 3.5 years. In vitro studies showed that the R1420H substitution decreases KATP channel activity. Identification of this loss-of-function variant in ABCC8 with a carrier frequency of 3.3% affects clinical care as homozygous inheritance and potential HHI will occur in 1/3,600 births in this American Indian population. PMID:26246406

  20. Wind modeling of Chihuahuan Desert dust outbreaks

    NASA Astrophysics Data System (ADS)

    Rivera Rivera, Nancy I.; Gill, Thomas E.; Gebhart, Kristi A.; Hand, Jennifer L.; Bleiweiss, Max P.; Fitzgerald, Rosa M.

    The Chihuahuan Desert region of North America is a significant source of mineral aerosols in the Western Hemisphere, and Chihuahuan Desert dust storms frequently impact the Paso del Norte (El Paso, USA/Ciudad Juarez, Mexico) metropolitan area. A statistical analysis of HYSPLIT back trajectory residence times evaluated airflow into El Paso on all days and on days with synoptic (non-convective) dust events in 2001-2005. The incremental probability—a measure of the areas most likely to have been traversed by air masses arriving at El Paso during dusty days—was only strongly positively associated with the region west-southwest of the city, a zone of known dust source areas. Focused case studies were made of major dust events on 15 April and 15 December 2003. Trajectories approached the surface and MM5 (NCAR/Penn State Mesoscale Model) wind speeds increased at locations consistent with dust sources observed in satellite imagery on those dates. Back trajectory and model analyses suggested that surface cyclones adjacent to the Chihuahuan Desert were associated with the extreme dust events, consistent with previous studies of dust storms in the Southern High Plains to the northeast. The recognition of these meteorological patterns serves as a forecast aid for prediction of dust events likely to impact the Paso del Norte.

  1. Sonoran Desert: Fragile Land of Extremes

    USGS Publications Warehouse

    Produced and Directed by Wessells, Stephen

    2003-01-01

    'Sonoran Desert: Fragile Land of Extremes' shows how biologists with the U.S. Geological Survey work with other scientists in an effort to better understand native plants and animals such as desert tortoises, saguaro cacti, and Gila monsters. Much of the program was shot in and around Saguaro National Park near Tucson, Arizona. Genetic detective work, using DNA, focuses on understanding the lives of tortoises. Studies of saguaros over many decades clarify how these amazing plants reproduce and thrive in the desert. Threats from fire, diseases in tortoises, and a growing human population motivate the scientists. Their work to identify how these organisms live and survive is a crucial step for the sound management of biological resources on public lands. This 28-minute program, USGS Open-File Report 03-305, was shot entirely in high definition video and produced by the USGS Western Ecological Research Center and Southwest Biological Science Center; produced and directed by Stephen Wessells, Western Region Office of Communications.

  2. 9. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 PALLADIAN WINDOW AT NORTH END OF CENTRAL HALL. 10. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 CENTRAL VIEW OF DOUBLE PARLORS FROM SOUTHWEST PARLOR TOWARD NORTHWEST PARLOR. 11. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 WALLPAPER IN SOUTHWEST PARLOR. 12. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 FIREPLACE IN SOUTHWEST PARLOR. 13. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 WINDOW IN SOUTHWEST PARLOR. 14. Historic American Buildings Survey, Laurence E. Tilley, Photographer April, 1958 DETAIL OF WALLPAPER AND WOODWORK IN ... - Eliza Ward House, 2 George Street, Providence, Providence County, RI

  3. Are Food Deserts Also Play Deserts?

    PubMed

    Cohen, Deborah A; Hunter, Gerald; Williamson, Stephanie; Dubowitz, Tamara

    2016-04-01

    Although food deserts are areas that lack easy access to food outlets and considered a barrier to a healthy diet and a healthy weight among residents, food deserts typically comprise older urban areas which may have many parks and street configurations that could facilitate more physical activity. However, other conditions may limit the use of available facilities in these areas. This paper assesses the use of parks in two Pittsburgh food desert neighborhoods by using systematic observation. We found that while the local parks were accessible, they were largely underutilized. We surveyed local residents and found that only a minority considered the parks unsafe for use during the day, but a substantial proportion suffered from health limitations that interfered with physical activity. Residents also felt that parks lacked programming and other amenities that could potentially draw more park users. Parks programming and equipment in food desert areas should be addressed to account for local preferences and adjusted to meet the needs and limitations of local residents, especially seniors.

  4. Deserts : geology and resources

    USGS Publications Warehouse

    Walker, Alta S.

    1996-01-01

    Approximately one-third of the Earth's land surface is desert, arid land with meager rainfall that supports only sparse vegetation and a limited population of people and animals. Deserts stark, sometimes mysterious worlds have been portrayed as fascinating environments of adventure and exploration from narratives such as that of Lawrence of Arabia to movies such as "Dune." These arid regions are called deserts because they are dry. They may be hot, they may be cold. They may be regions of sand or vast areas of rocks and gravel peppered with occasional plants. But deserts are always dry. Deserts are natural laboratories in which to study the interactions of wind and sometimes water on the arid surfaces of planets. They contain valuable mineral deposits that were formed in the arid environment or that were exposed by erosion. Because deserts are dry, they are ideal places for human artifacts and fossils to be preserved. Deserts are also fragile environments. The misuse of these lands is a serious and growing problem in parts of our world.

  5. The effect of drought on four plant communities in the northern Mojave Desert

    SciTech Connect

    Schultz, B.W.; Ostler, W.K.

    1993-12-31

    Desert plant communities contain many perennial plant species that are well adapted to arid environments; therefore, one would intuitively believe that perennial desert species readily survive drought conditions. Abundant research on plant-soil-water relationships in North American deserts has shown that many species can maintain water uptake and growth when the soil-water potential is low. Little research, however, has focused on how prolonged drought conditions affect plant species in vegetation associations in desert ecosystems. A prolonged and widespread drought occurred in much of the western United States, including the Northern Mojave Desert, from 1987 through 1991. During this drought period vegetation characterization studies, initiated in 1990, by the US Department of Energy (DOE) at Yucca Mountain, Nevada, allowed EG and G Energy Measurements to collect data that could be used to infer how both desert vegetation associations and desert plant species reacted to a prolonged drought. This paper presents the preliminary results.

  6. Using terrestrial light detection and ranging (lidar) technology for land-surface analysis in the Southwest

    USGS Publications Warehouse

    Soulard, Christopher E.; Bogle, Rian C.

    2011-01-01

    Emerging technologies provide scientists with methods to measure Earth processes in new ways. One of these technologies--ultra-high-resolution, ground-based light detection and ranging (lidar)--is being used by USGS Western Geographic Science Center scientists to characterize the role of wind and fire processes in shaping desert landscapes of the Southwest United States.

  7. What is Desert RATS?

    NASA Video Gallery

    The mission manager and test coordinators for the 2011 mission explain why Desert RATS was started 14 years ago, questions being studied in this year's activities, technologies being tested and the...

  8. Nelson's big horn sheep (Ovis canadensis nelsoni) trample Agassiz's desert tortoise (Gopherus agassizii) burrow at a California wind energy facility

    USGS Publications Warehouse

    Agha, Mickey; Delaney, David F.; Lovich, Jeffrey E.; Briggs, Jessica; Austin, Meaghan; Price, Steven J.

    2015-01-01

    Research on interactions between Agassiz's desert tortoises (Gopherus agassizii) and ungulates has focused exclusively on the effects of livestock grazing on tortoises and their habitat (Oldemeyer, 1994). For example, during a 1980 study in San Bernardino County, California, 164 desert tortoise burrows were assessed for vulnerability to trampling by domestic sheep (Ovis aries). Herds of grazing sheep damaged 10% and destroyed 4% of the burrows (Nicholson and Humphreys 1981). In addition, a juvenile desert tortoise was trapped and an adult male was blocked from entering a burrow due to trampling by domestic sheep. Another study found that domestic cattle (Bos taurus) trampled active desert tortoise burrows and vegetation surrounding burrows (Avery and Neibergs 1997). Trampling also has negative impacts on diversity of vegetation and intershrub soil crusts in the desert southwest (Webb and Stielstra 1979). Trampling of important food plants and overgrazing has the potential to create competition between desert tortoises and domestic livestock (Berry 1978; Coombs 1979; Webb and Stielstra 1979).

  9. High concentrations of regional dust from deserts to plains across the central Rocky Mountains, USA

    NASA Astrophysics Data System (ADS)

    Reynolds, R. L.; Munson, S. M.; Fernandez, D. P.; Neff, J. C.

    2015-12-01

    Regional mineral dust in the American Southwest affects snow-melt rates, biogeochemical cycling, visibility, and public health. We measured total suspended particulates (TSP) across a 500-km-long sampling network of five remote sites in Utah and Colorado, USA, forming a gradient in distance from major dust emitting areas. The two westernmost sites on the Colorado Plateau desert had similar TSP concentrations (2008-2012, daily average=126 μg m-3; max. daily average over a two-week period=700 μg m-3 at Canyonlands National Park, Utah), while the easternmost High Plains site, close to cropped and grazed areas in northeastern Colorado, had an average concentration of 143 μg m-3 in 2011-2012 (max. daily average=656 μg m-3). Such concentrations rank comparably with those of TSP in several African and Asian cities in the paths of frequent dust storms. Dust loadings at the two intervening montane sites decreased from the western slope of the Rocky Mountains (Telluride, daily average=68 μg m-3) to an eastern site (Niwot Ridge, daily average=58 μg m-3). Back-trajectory analyses and satellite retrievals indicated that the three westernmost sites received most dust from large desert-source regions as far as 300 km to their southwest. These sources also sometimes sent dust to the two easternmost sites, which additionally captured dust from sources north and northwest of the central Rocky Mountains as well as locally at the Plains site. The PM10 fraction accounted for <15% of TSP, but most TSP is only slightly larger (typical median size, 15-20 μm) after about 100-800 km transport distances. Correlations between TSP and PM10 values indicate increases in both fractions during regional wind storms, especially related to Pacific frontal systems during late winter to late spring. These measurements and observations indicate that most dust deposition and associated air-quality problems in the interior American West are connected to regional dust sources and not to those in

  10. Inferences about winter temperatures and summer rains from the late Quaternary record of C4 perennial grasses and C3 desert shrubs in the northern Chihuahuan Desert

    USGS Publications Warehouse

    Holmgren, Camille A.; Norris, Jodi; Betancourt, Julio L.

    2007-01-01

    Late Quaternary histories of two North American desert biomes—C4 grasslands and C3 shrublands—are poorly known despite their sensitivity and potential value in reconstructing summer rains and winter temperatures. Plant macrofossil assemblages from packrat midden series in the northern Chihuahuan Desert show that C4 grasses and annuals typical of desert grassland persisted near their present northern limits throughout the last glacial-interglacial cycle. By contrast, key C3 desert shrubs appeared somewhat abruptly after 5000cal.yrBP. Bioclimatic envelopes for select C4 and C3 species are mapped to interpret the glacial-interglacial persistence of desert grassland and the mid-to-late Holocene expansion of desert shrublands. The envelopes suggest relatively warm Pleistocene temperatures with moist summers allowed for persistence of C4 grasses, whereas winters were probably too cold (or too wet) for C3 desert shrubs. Contrary to climate model results, core processes associated with the North American Monsoon and moisture transport to the northern Chihuahuan Desert remained intact throughout the last glacial-interglacial cycle. Mid-latitude effects, however, truncated midsummer (July-August) moisture transport north of 35° N. The sudden expansion of desert shrublands after 5000cal.yrBP may be a threshold response to warmer winters associated with increasing boreal winter insolation, and enhanced El Niño-Southern Oscillation variability.

  11. Reclaiming freshwater sustainability in the Cadillac Desert

    PubMed Central

    Sabo, John L.; Sinha, Tushar; Bowling, Laura C.; Schoups, Gerrit H. W.; Wallender, Wesley W.; Campana, Michael E.; Cherkauer, Keith A.; Fuller, Pam L.; Graf, William L.; Hopmans, Jan W.; Kominoski, John S.; Taylor, Carissa; Trimble, Stanley W.; Webb, Robert H.; Wohl, Ellen E.

    2010-01-01

    Increasing human appropriation of freshwater resources presents a tangible limit to the sustainability of cities, agriculture, and ecosystems in the western United States. Marc Reisner tackles this theme in his 1986 classic Cadillac Desert: The American West and Its Disappearing Water. Reisner's analysis paints a portrait of region-wide hydrologic dysfunction in the western United States, suggesting that the storage capacity of reservoirs will be impaired by sediment infilling, croplands will be rendered infertile by salt, and water scarcity will pit growing desert cities against agribusiness in the face of dwindling water resources. Here we evaluate these claims using the best available data and scientific tools. Our analysis provides strong scientific support for many of Reisner's claims, except the notion that reservoir storage is imminently threatened by sediment. More broadly, we estimate that the equivalent of nearly 76% of streamflow in the Cadillac Desert region is currently appropriated by humans, and this figure could rise to nearly 86% under a doubling of the region's population. Thus, Reisner's incisive journalism led him to the same conclusions as those rendered by copious data, modern scientific tools, and the application of a more genuine scientific method. We close with a prospectus for reclaiming freshwater sustainability in the Cadillac Desert, including a suite of recommendations for reducing region-wide human appropriation of streamflow to a target level of 60%. PMID:21149727

  12. Reclaiming freshwater sustainability in the Cadillac Desert.

    PubMed

    Sabo, John L; Sinha, Tushar; Bowling, Laura C; Schoups, Gerrit H W; Wallender, Wesley W; Campana, Michael E; Cherkauer, Keith A; Fuller, Pam L; Graf, William L; Hopmans, Jan W; Kominoski, John S; Taylor, Carissa; Trimble, Stanley W; Webb, Robert H; Wohl, Ellen E

    2010-12-14

    Increasing human appropriation of freshwater resources presents a tangible limit to the sustainability of cities, agriculture, and ecosystems in the western United States. Marc Reisner tackles this theme in his 1986 classic Cadillac Desert: The American West and Its Disappearing Water. Reisner's analysis paints a portrait of region-wide hydrologic dysfunction in the western United States, suggesting that the storage capacity of reservoirs will be impaired by sediment infilling, croplands will be rendered infertile by salt, and water scarcity will pit growing desert cities against agribusiness in the face of dwindling water resources. Here we evaluate these claims using the best available data and scientific tools. Our analysis provides strong scientific support for many of Reisner's claims, except the notion that reservoir storage is imminently threatened by sediment. More broadly, we estimate that the equivalent of nearly 76% of streamflow in the Cadillac Desert region is currently appropriated by humans, and this figure could rise to nearly 86% under a doubling of the region's population. Thus, Reisner's incisive journalism led him to the same conclusions as those rendered by copious data, modern scientific tools, and the application of a more genuine scientific method. We close with a prospectus for reclaiming freshwater sustainability in the Cadillac Desert, including a suite of recommendations for reducing region-wide human appropriation of streamflow to a target level of 60%. PMID:21149727

  13. Reclaiming freshwater sustainability in the Cadillac Desert

    USGS Publications Warehouse

    Sabo, John L.; Sinha, Tushar; Bowling, Laura C.; Schoups, Gerrit H.W.; Wallender, Wesley W.; Campana, Michael E.; Cherkauer, Keith A.; Fuller, Pam L.; Graf, William L.; Hopmans, Jan W.; Kominoski, John S.; Taylor, Carissa; Trimble, Stanley W.; Webb, Robert H.; Wohl, Ellen E.

    2010-01-01

    Increasing human appropriation of freshwater resources presents a tangible limit to the sustainability of cities, agriculture, and ecosystems in the western United States. Marc Reisner tackles this theme in his 1986 classic Cadillac Desert: The American West and Its Disappearing Water. Reisner's analysis paints a portrait of region-wide hydrologic dysfunction in the western United States, suggesting that the storage capacity of reservoirs will be impaired by sediment infilling, croplands will be rendered infertile by salt, and water scarcity will pit growing desert cities against agribusiness in the face of dwindling water resources. Here we evaluate these claims using the best available data and scientific tools. Our analysis provides strong scientific support for many of Reisner's claims, except the notion that reservoir storage is imminently threatened by sediment. More broadly, we estimate that the equivalent of nearly 76% of streamflow in the Cadillac Desert region is currently appropriated by humans, and this figure could rise to nearly 86% under a doubling of the region's population. Thus, Reisner's incisive journalism led him to the same conclusions as those rendered by copious data, modern scientific tools, and the application of a more genuine scientific method. We close with a prospectus for reclaiming freshwater sustainability in the Cadillac Desert, including a suite of recommendations for reducing region-wide human appropriation of streamflow to a target level of 60%.

  14. Reclaiming freshwater sustainability in the Cadillac Desert.

    PubMed

    Sabo, John L; Sinha, Tushar; Bowling, Laura C; Schoups, Gerrit H W; Wallender, Wesley W; Campana, Michael E; Cherkauer, Keith A; Fuller, Pam L; Graf, William L; Hopmans, Jan W; Kominoski, John S; Taylor, Carissa; Trimble, Stanley W; Webb, Robert H; Wohl, Ellen E

    2010-12-14

    Increasing human appropriation of freshwater resources presents a tangible limit to the sustainability of cities, agriculture, and ecosystems in the western United States. Marc Reisner tackles this theme in his 1986 classic Cadillac Desert: The American West and Its Disappearing Water. Reisner's analysis paints a portrait of region-wide hydrologic dysfunction in the western United States, suggesting that the storage capacity of reservoirs will be impaired by sediment infilling, croplands will be rendered infertile by salt, and water scarcity will pit growing desert cities against agribusiness in the face of dwindling water resources. Here we evaluate these claims using the best available data and scientific tools. Our analysis provides strong scientific support for many of Reisner's claims, except the notion that reservoir storage is imminently threatened by sediment. More broadly, we estimate that the equivalent of nearly 76% of streamflow in the Cadillac Desert region is currently appropriated by humans, and this figure could rise to nearly 86% under a doubling of the region's population. Thus, Reisner's incisive journalism led him to the same conclusions as those rendered by copious data, modern scientific tools, and the application of a more genuine scientific method. We close with a prospectus for reclaiming freshwater sustainability in the Cadillac Desert, including a suite of recommendations for reducing region-wide human appropriation of streamflow to a target level of 60%.

  15. 3. Historic American Buildings Survey Nathaniel R. Ewan, Photographer March ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Nathaniel R. Ewan, Photographer March 12, 1937 EXTERIOR - DETAIL BLAST FURNACE - WEST ELEVATION - The Deserted Village, Blast Furnace, Allaire, Monmouth County, NJ

  16. A Comparison of One-Dimensional Hydrologic Models Using Soil Moisture Observations under Urban Irrigation in a Desert Climate

    NASA Astrophysics Data System (ADS)

    Volo, T. J.; Vivoni, E. R.; Martin, C. A.; Wang, Z.; Ruddell, B.

    2012-12-01

    Through the past several decades, rapid population growth in the arid American Southwest has dramatically changed patterns of plant-available water through municipal and residential irrigation systems that provide supplemental water to designed and managed urban landscape vegetation. Urban irrigation, including diversion of rainwater and addition of imported water, has thereby enabled the transformation of areas once covered by bare soil and low water-use, native desert plant species to large tracts of exotic, high water-use turf grass and shade trees. Despite the large percentage of residential water appropriated to irrigation purposes, models of urban hydrology often fail to include the impact that this anthropogenic input has on water, energy, and biomass conditions. This study utilizes two one-dimensional soil moisture models to examine the importance of representing different processes in a quantitative urban ecohydrology model under irrigation scenarios. Such processes include sub-daily energy fluxes, vertical redistribution of soil moisture, saturation- and infiltration-excess runoff mechanisms, seasonally variable irrigation scheduling, and soil moisture control on evapotranspiration rates. The analysis is informed by soil moisture observations from an experimental sensor network in the Phoenix, Arizona metropolitan area. The network includes data from several different landscape and irrigation treatments representative of pre- and post-development conditions in the region. By interpreting soil moisture levels in terms of plant water stress, this study analyzes the effectiveness of urban irrigation practices in arid climates. Furthermore, by identifying the necessary hydrologic processes to represent in an urban ecohydrology model, our results inform future work in adapting a distributed hydrologic model to desert urban settings where irrigation plays a significant role in minimizing plant water stress. An appropriate model of water and energy balances

  17. Looking Southwest at Southwest End of Erbia Building Showing Typical ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Southwest at Southwest End of Erbia Building Showing Typical Wall and Roof Juncture Including a Recycling Furnace - Hematite Fuel Fabrication Facility, Erbia Plant, 3300 State Road P, Festus, Jefferson County, MO

  18. Interior of southwest vault, opened southwest vault door, closed southeast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior of southwest vault, opened southwest vault door, closed southeast vault door, and evidence of forced entry in north interior wall. View from west interior wall of southwest vault. Facing east. - Travis Air Force Base, Building No. 925, W Street, Fairfield, Solano County, CA

  19. Environmental Science: Activities with Plants of the Southwest.

    ERIC Educational Resources Information Center

    Hackley, Sharon; Hackley, Mike

    In this book for students of all ages, the author introduces unusual recipe ideas for the prickly, odd, and pestiferous plants of the American southwestern desert. Students are involved in cooking activities designed to spark interest in ecology, trigger logical thinking, utilize math skills, and build sound environmental concepts. Care was taken…

  20. A Systematic Review of Wild Burro Grazing Effects on Mojave Desert Vegetation, USA

    NASA Astrophysics Data System (ADS)

    Abella, Scott R.

    2008-06-01

    Wild burros ( Equus asinus), protected by the 1971 Wild Free-Roaming Horse and Burro Act on some federal lands but exotic animals many ecologists and resource mangers view as damaging to native ecosystems, represent one of the most contentious environmental management problems in American Southwest arid lands. This review synthesizes the scattered literature about burro effects on plant communities of the Mojave Desert, a center of burro management contentions. I classified 24 documents meeting selection criteria for this review into five categories of research: (i) diet analyses directly determining which plant species burros consume, (ii) utilization studies of individual species, (iii) control-impact comparisons, (iv) exclosure studies, and (v) forage analyses examining chemical characteristics of forage plants. Ten diet studies recorded 175 total species that burros consumed. However, these studies and two exclosure studies suggested that burros preferentially eat graminoid and forb groups over shrubs. One study in Death Valley National Park, for example, found that Achnatherum hymenoides (Indian ricegrass) was 11 times more abundant in burro diets than expected based on its availability. Utilization studies revealed that burros also exhibit preferences within the shrub group. Eighty-three percent of reviewed documents were produced in a 12-year period, from 1972 to 1983, with the most recent document produced in 1988. Because burros remain abundant on many federal lands and grazing may interact with other management concerns (e.g., desert wildfires fueled by exotic grasses), rejuvenating grazing research to better understand both past and present burro effects could help guide revegetation and grazing management scenarios.

  1. A systematic review of wild burro grazing effects on Mojave Desert vegetation, USA.

    PubMed

    Abella, Scott R

    2008-06-01

    Wild burros (Equus asinus), protected by the 1971 Wild Free-Roaming Horse and Burro Act on some federal lands but exotic animals many ecologists and resource mangers view as damaging to native ecosystems, represent one of the most contentious environmental management problems in American Southwest arid lands. This review synthesizes the scattered literature about burro effects on plant communities of the Mojave Desert, a center of burro management contentions. I classified 24 documents meeting selection criteria for this review into five categories of research: (i) diet analyses directly determining which plant species burros consume, (ii) utilization studies of individual species, (iii) control-impact comparisons, (iv) exclosure studies, and (v) forage analyses examining chemical characteristics of forage plants. Ten diet studies recorded 175 total species that burros consumed. However, these studies and two exclosure studies suggested that burros preferentially eat graminoid and forb groups over shrubs. One study in Death Valley National Park, for example, found that Achnatherum hymenoides (Indian ricegrass) was 11 times more abundant in burro diets than expected based on its availability. Utilization studies revealed that burros also exhibit preferences within the shrub group. Eighty-three percent of reviewed documents were produced in a 12-year period, from 1972 to 1983, with the most recent document produced in 1988. Because burros remain abundant on many federal lands and grazing may interact with other management concerns (e.g., desert wildfires fueled by exotic grasses), rejuvenating grazing research to better understand both past and present burro effects could help guide revegetation and grazing management scenarios. PMID:18379838

  2. Evaluation of the Landsat-5 TM radiometric calibration history using desert test sites

    NASA Astrophysics Data System (ADS)

    Markham, Brian L.; Barsi, Julia A.; Helder, Dennis L.; Thome, Kurtis J.; Barker, John L.

    2006-09-01

    The U.S. radiometric calibration procedure for the reflective bands of the Landsat-5 Thematic Mapper was updated in May 2003. This update was based on a model of the performance of the instrument developed from its response to the best-behaved internal calibration lamp and from a cross calibration with Landsat-7 ETM+ that occurred in June 1999. Since this update was performed, there have been continued attempts to validate the model. These validations have relied primarily upon data acquired over deserts of the world. These studies have been limited by the amount of data available over any one site for the 22-year life of the mission. Initial attempts over the desert Southwest of the United States were inconclusive, though they were suggestive of additional degradation occurring in the shorter wavelength channels. More recently, significant holdings from European Space Agency of data over North Africa have been made available for analysis. The North Africa test area results to date for one site in Libya are considerably less noisy than the North American datasets. They indicate an exponential-like decay of about 19%, 16%, 8% and 4% for TM bands 1, 2, 3 and 4, with the degradation, at least in bands 1 and 2 occurring throughout the mission. The current model shows changes of roughly the same magnitude, but with the change occurring more rapidly so that nearly all the change is completed in 4 years. These results are generally consistent with independent work going on outside of this effort. Additional sites are being analyzed as data become available.

  3. Children's Literature of the Southwest: Creative Springboard to Integrating the Language Arts.

    ERIC Educational Resources Information Center

    Whitmer, Jean E.

    Using children's books that reflect the cultural heritage of the American Southwest, this paper offers suggestions for integrating the language arts through reading, writing, and listening activities. Activities are arranged into two sections: (1) integrated language arts approaches to writing springing from Southwest picture books by Byrd Baylor,…

  4. Plants of the Desert.

    ERIC Educational Resources Information Center

    NatureScope, 1985

    1985-01-01

    Provides background information and student activities on plants of the desert, including various adaptations for life with limited water supplies. Each activity includes objective(s), recommended age level(s), subject area(s), list of materials needed, and procedures. A ready-to-copy student worksheet is included. (DH)

  5. How desert varnish forms?

    NASA Astrophysics Data System (ADS)

    Perry, Randall S.; Kolb, Vera M.; Lynne, Bridget Y.; Sephton, Mark A.; Mcloughlin, Nicola; Engel, Michael H.; Olendzenski, Lorraine; Brasier, Martin; Staley, James T., Jr.

    2005-09-01

    Desert varnish is a black, manganese-rich rock coating that is widespread on Earth. The mechanism underlying its formation, however, has remained unresolved. We present here new data and an associated model for how desert varnish forms, which substantively challenges previously accepted models. We tested both inorganic processes (e.g. clays and oxides cementing coatings) and microbial methods of formation. Techniques used in this preliminary study include SEM-EDAX with backscatter, HRTEM of focused ion beam prepared (FIB) wafers and several other methods including XRPD, Raman spectroscopy, XPS and Tof-SIMS. The only hypothesis capable of explaining a high water content, the presence of organic compounds, an amorphous silica phase (opal-A) and lesser quantities of clays than previously reported, is a mechanism involving the mobilization and redistribution of silica. The discovery of silica in desert varnish suggests labile organics are preserved by interaction with condensing silicic acid. Organisms are not needed for desert varnish formation but Bacteria, Archaea, Eukarya, and other organic compounds are passively incorporated and preserved as organominerals. The rock coatings thus provide useful records of past environments on Earth and possibly other planets. Additionally this model also helps to explain the origin of key varnish and rock glaze features, including their hardness, the nature of the "glue" that binds heterogeneous components together, its layered botryoidal morphology, and its slow rate of formation.

  6. 2. Historic American Buildings Survey W. N. Manning, Photographer, March ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey W. N. Manning, Photographer, March 23, 1934. FRONT VIEW. - SOUTHWEST - Summerfield College, Music Building, Main & College Streets, Summerfield, Dallas County, AL

  7. 1. Historic American Buildings Survey Arthur C. Haskell, Photographer April, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Arthur C. Haskell, Photographer April, 1934 (b) LIGHTHOUSE AND KEEPER'S COTTAGE FROM SOUTHWEST - Lighthouse, Cedar Point Scituate Harbor, Scituate, Plymouth County, MA

  8. 2. Historic American Buildings Survey R. Merritt Lacey, Photographer May ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey R. Merritt Lacey, Photographer May 6, 1936 EXTERIOR - SOUTHEAST ELEVATION AND SOUTHWEST END - Cornwallis Headquarters, Palisade Interstate Park, Alpine, Bergen County, NJ

  9. 2. Historic American Buildings Survey Lester Jones, Photographer March 2, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Lester Jones, Photographer March 2, 1940 GENERAL VIEW FROM SOUTHWEST - Fort Smith, Commissary Building, 100 South Garrison Avenue, Fort Smith, Sebastian County, AR

  10. 3. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, 1934 VIEW FROM SOUTHWEST - Felix & Odile Pratt Valle House, Merchant & Second Streets, Sainte Genevieve, Ste. Genevieve County, MO

  11. 1. Historic American Buildings Survey Russell Jones, Photographer June 1963 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Russell Jones, Photographer June 1963 SOUTHWEST VIEW - Abner Cloud House, Intersection of Canal Road & Reservoir Road Northwest, Washington, District of Columbia, DC

  12. 4. Historic American Buildings Survey Jack Maley, Photographer May 31, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey Jack Maley, Photographer May 31, 1978 SOUTHWEST (FRONT) AND SOUTHEAST (SIDE) ELEVATIONS - Franklin Park Zoo, Elephant House, Seaver Street, Boston, Suffolk County, MA

  13. 2. Historic American Buildings Survey Jack Maley, Photographer May 31, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Jack Maley, Photographer May 31, 1978 SOUTHWEST (FRONT) AND NORTHWEST (SIDE) ELEVATION - Franklin Park Zoo, Feline House, Seaver Street, Boston, Suffolk County, MA

  14. 1. Historic American Buildings Survey Jack Maley, Photographer May 31, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Jack Maley, Photographer May 31, 1978 SOUTHWEST (FRONT) AND SOUTHEAST (SIDE) ELEVATION - Franklin Park Zoo, Feline House, Seaver Street, Boston, Suffolk County, MA

  15. 1. Historic American Buildings Survey Jack Maley, Photographer May 31, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Jack Maley, Photographer May 31, 1978 SOUTHWEST (FRONT) AND NORTHWEST (SIDE) ELEVATIONS - Franklin Park Zoo, Elephant House, Seaver Street, Boston, Suffolk County, MA

  16. Historic American Buildings Survey Marc Blair Photographer, summer 1966 SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Historic American Buildings Survey Marc Blair Photographer, summer 1966 SOUTH ELEVATION from SOUTHWEST - Grace Protestant Episcopal Church, 1041 Wisconsin Avenue Northwest, Washington, District of Columbia, DC

  17. 9. Historic American Buildings Survey, John A. Bryan, Photographer July ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Historic American Buildings Survey, John A. Bryan, Photographer July 9, 1952 SOUTHWEST PERSPECTIVE. - St. John's Episcopal Mission, Chapel & Rectory, Fort Bennett Vicinity, Green Grass, Dewey County, SD

  18. 2. Historic American Buildings Survey James Butters, Photographer April 8, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey James Butters, Photographer April 8, 1936 GENERAL REAR VIEW (SOUTHWEST ELEVATION) - Hope Farm (Villa), Auburn Avenue & Homochitto Street, Natchez, Adams County, MS

  19. 1. Historic American Buildings Survey James Butters, Photographer. Mar, 28, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey James Butters, Photographer. Mar, 28, 1936. GENERAL FRONT VIEW (SOUTHWEST ELEVATION) - Marschalk Printing Office, Wall & Franklin Streets, Natchez, Adams County, MS

  20. 1. Historic American Buildings Survey Lester Jones, Photographer February 28, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Lester Jones, Photographer February 28, 1940 SLAVE HOSPITAL FROM THE SOUTHWEST - Melrose Plantation, Slave Hospital, State Highway 119, Melrose, Natchitoches Parish, LA

  1. Credit PSR. This image depicts the southwest and southeast facades ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Credit PSR. This image depicts the southwest and southeast facades as seen when looking north. The concrete block lean-to in the foreground is the facility control room. Between this room and the X-ray room is a four foot thick concrete wall (which can be seen as a "step" between the lowest and highest roof planes) intended as X-ray shielding for operators. The X-ray chamber faces away from the JPL Edwards Facility toward a fenced desert area - Jet Propulsion Laboratory Edwards Facility, Radiographic Inspection Building, Edwards Air Force Base, Boron, Kern County, CA

  2. View of large workroom on southwest corner of second floor ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of large workroom on southwest corner of second floor interior, American Railway Express Building, looking to the east. View shows corner office, boxed wood ceiling beams and wood support posts - Southern Pacific Railroad Depot, Railroad Terminal Post Office & Express Building, Fifth & I Streets, Sacramento, Sacramento County, CA

  3. Borderlands of the Southwest: An Exercise in Geographical History

    ERIC Educational Resources Information Center

    Thornton, Stephen J.

    2013-01-01

    In this article, the author argues that geography is more than a passive backdrop to time and events. Geographical perception is culturally mediated. He examines the case of the American Southwest and how its geography and historical heritage have been portrayed and how they might be otherwise if viewed through a different lens. (Contains 12…

  4. 7. DETAIL OF INTAKE PIER, LOOKING SOUTHWEST FROM EASTERN SACRAMENTO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. DETAIL OF INTAKE PIER, LOOKING SOUTHWEST FROM EASTERN SACRAMENTO LEVEE. - Sacramento River Water Treatment Plant Intake Pier & Access Bridge, Spanning Sacramento River approximately 175 feet west of eastern levee on river; roughly .5 mile downstream from confluence of Sacramento & American Rivers, Sacramento, Sacramento County, CA

  5. A study of Desert Dermatoses in the Thar Desert Region

    PubMed Central

    Chatterjee, Manas; Vasudevan, Biju

    2015-01-01

    Introduction: Desert dermatology describes the cutaneous changes and the diseases affecting those living in the desert. Diurnal variation in temperature is high and is characteristic of the deserts. The lack of water affects daily activities and impacts dermatological conditions. Adaptation to the desert is therefore important to survival. This original article focuses on dermatoses occurring in a population in the Thar desert of India, predominantly located in Rajasthan. Materials and Methods: This is a descriptive study involving various dermatoses seen in patients residing in the Thar desert region over a duration of 3 years. Results: Infections were the most common condition seen among this population and among them fungal infections were the most common. The high incidence of these infections would be accounted for by the poor hygienic conditions due to lack of bathing facilities due to scarcity of water and the consequent sweat retention and overgrowth of cutaneous infective organisms. Pigmentary disorders, photodermatoses, leishmaniasis and skin tumors were found to be more prevalent in this region. Desert sweat dermatitis was another specific condition found to have an increased incidence. Conclusion: The environment of the desert provides for a wide variety of dermatoses that can result in these regions with few of these dermatoses found in much higher incidence than in other regions. The concept of desert dermatology needs to be understood in more details to provide better care to those suffering from desert dermatoses and this article is a step forward in this regard. PMID:25657392

  6. Millennial-scale records of North American Monsoon in time and space during the last glacial period: reconstructions from arid northern Mexico

    NASA Astrophysics Data System (ADS)

    Roy, P.; Quiroz-Jiménez, D.; Charles-Polo, M.; Lozano-Santacruz, R.

    2013-05-01

    The arid northern Mexico is part of the Sonora and Chihuahua Deserts and both the deserts belong to the North American Desert system. The North American Monsoon (NAM) or Mexican Monsoon refers to the system that brings summer precipitation to arid northern Mexico and southwestern USA. It contributes ca. 70-80% of total annual precipitation along the western slopes of the Sierra Madre Occidental (northern Mexico) and ca. 40-50% of total precipitation in Arizona and New Mexico (southwest USA). High-resolution geochemical data from lacustrine deposits located between 23°N and 31°N (paleolakes La Salada, Babicora and San Felipe) provide spatio-temporal and millennial-scale paleohydrological records related to the dynamics of summer precipitation as well as westerly winter storms over the last glacial period. The inverse relationship between proxy records of runoff into lacustrine basins of northern Mexico and winter precipitation over the southwestern USA indicate that the westerly winter storms had minimal influence south of 30°N and the paleohydrological changes are mainly summer precipitation controlled. The variation in summer season precipitation between 20 and 60 cal. kyr BP was driven by long term changes in summer insolation. During an interval of lower summer insolation (i.e. >60 cal. kyr BP), the higher summer precipitation could be related to the NAM expansion as a result of reduced north hemisphere ice sheets. On a millennial-scale, the region received more than average precipitation during the warm interstadials and vice versa.

  7. Range and habitats of the desert tortoise

    USGS Publications Warehouse

    Germano, D.J.; Bury, R.B.; Esque, T.C.; Fritts, T.H.; Bury, R.B.; Germano, D.J.

    1994-01-01

    We determined the current range of the desert tortoise (Gopherus agassizii) based on the available latest data from government agencies, the literature, and our experience. We developed the first detailed range map of this species and summarized information about habitat preferences. New records of occurrences were incorporated, and some peripheral localities of questionable authenticity were deleted. The distribution oCG. agassizii covers the broadest range of latitude, climatic regimes, habitats, and biotic regions of any North American tortoise. The northern portion ofits range is in the Mojave Desert of sDuth"eastern California, southern Nevada, southwestern Utah, and northwestern Arizona. The central portion of the range consists of several subdivisions of the Sonaran Desert in southeastern California, western and southern Arizona, and western Sonora, Mexico. The southern edge of its range is in the semitropical Sinaloan thornscrub and Sinaloan deciduous forest of eastern Sonora and northern Sinaloa, Mexico. This species has marked geogi-aphic differences but seems to construct burrows throughout its range.

  8. General Information about Native Americans. Native American Curriculum Series.

    ERIC Educational Resources Information Center

    Ross, Cathy; Fernandes, Roger

    The first in a series of Native American instructional materials, this booklet introduces elementary students to the culture and history of woodland, plains, desert, and coastal Indians. It presents an overview of philosophies common to most Native American cultures, differentiates the four Indian culture areas, and guides students in identifying…

  9. Deserts of China

    USGS Publications Warehouse

    Walker, Alta S.

    1982-01-01

    Improving arid land quality requires an understanding of the original state of the land and its relationship to wind, water, and plant regimes, as well as understanding of interactions within the present ecosystem.  Chinese scientists and local residents have made significant advances in improving arid environments in gobi and sandy deserts and in less arid sandy lands.  Wind patterns are being changed by planting forest belts to protect oases and sandy lands, and on a smaller scale by planting grasses and shrubs or constructing straw grids.  Research on reclamation of deserts is now focusing on how sand-fixing plants may be adapted to local environments, and how the resources of grazing land and water may be effectively exploited without being overused.

  10. Southwestern desert resources

    USGS Publications Warehouse

    Halvorson, William L.; van Riper, Charles; Schwalbe, Cecil R.

    2010-01-01

    The southwestern deserts stretch from southeastern California to west Texas and then south to central Mexico. The landscape of this region is known as basin and range topography featuring to "sky islands" of forest rising from the desert lowlands which creates a uniquely diverse ecology. The region is further complicated by an international border, where governments have caused difficulties for many animal populations. This book puts a spotlight on individual research projects which are specific examples of work being done in the area and when they are all brought together, to shed a general light of understanding the biological and cultural resources of this vast region so that those same resources can be managed as effectively and efficiently as possible. The intent is to show that collaborative efforts among federal, state agency, university, and private sector researchers working with land managers, provides better science and better management than when scientists and land managers work independently.

  11. Namib Desert, Namibia, Africa

    NASA Technical Reports Server (NTRS)

    1990-01-01

    One of the driest regions on Earth, the Namib Desert, Namibia, Africa (23.0N, 15.0E) lies adjacent to the Atlantic coast but the upwelling oceanic water causes a very stable rainless atmosphere. The few local inland rivers do not reach the sea but instead, appear as long indentations where they penetrate the dune fields and end as small dry lakes. The vast dune fields are the result of sands deposited over millions of years by the stream flow.

  12. Namib Desert, Namibia, Africa

    NASA Technical Reports Server (NTRS)

    1990-01-01

    One of the driest regions on Earth, the Namib Desert, Namibia, Africa (23.0N, 15.0E) lies adjacent to the Atlantic coast but upwelling oceanic water causes a very stable rainless atmosphere. The few local inland rivers do not reach the sea but instead appear as long indentations where rivers penetrate the dune fields and end as small dry lakes. The vast dune fields are the result of sands deposited over millions of years by the stream flow.

  13. Aquaporins in desert rodent physiology.

    PubMed

    Pannabecker, Thomas L

    2015-08-01

    Desert rodents face a sizeable challenge in maintaining salt and water homeostasis due to their life in an arid environment. A number of their organ systems exhibit functional characteristics that limit water loss above that which occurs in non-desert species under similar conditions. These systems include renal, pulmonary, gastrointestinal, nasal, and skin epithelia. The desert rodent kidney preserves body water by producing a highly concentrated urine that reaches a maximum osmolality nearly three times that of the common laboratory rat. The precise mechanism by which urine is concentrated in any mammal is unknown. Insights into the process may be more apparent in species that produce highly concentrated urine. Aquaporin water channels play a fundamental role in water transport in several desert rodent organ systems. The role of aquaporins in facilitating highly effective water preservation in desert rodents is only beginning to be explored. The organ systems of desert rodents and their associated AQPs are described.

  14. The Desert Crossings of Mars

    NASA Astrophysics Data System (ADS)

    Cockell, C. S.

    Apart from the polar caps, the Martian volcanoes and the Valles Marineris, ~80% of the martian surface can essentially be classified as `desert'. The methods used to explore Mars, the scientific priorities and the philo- sophical and historical precedents that drive human exploration on Mars will primarily come from our experiences in terrestrial deserts. Here, the methods and approaches used for terrestrial desert expeditions are discussed with reference to Mars. Some of the physical challenges such as low temperature and frost formation will be akin to cold polar desert exploration on Earth. However, some challenges, such as dust storms and lack of liquid water will be akin to hot desert exploration. Expeditions that draw the appropriate lessons from both hot and cold desert terrestrial expeditions will succeed. Examples of major regions on Mars that might be regarded as significant exploratory challenges for expeditions are identified. Key parameters of these expeditions including distance and plausible scientific objectives are provided.

  15. Jeeps Penetrating a Hostile Desert

    ERIC Educational Resources Information Center

    Bailey, Herb

    2009-01-01

    Several jeeps are poised at base camp on the edge of a desert aiming to escort one of them as far as possible into the desert, while the others return to camp. They all have full tanks of gas and share their fuel to maximize penetration. In a friendly desert it is best to leave caches of fuel along the way to help returning jeeps. We solve the…

  16. Microbial origin of desert varnish.

    PubMed

    Dorn, R I; Oberlander, T M

    1981-09-11

    Scanning electron microscopy and energy dispersive x-ray analyses of desert varnish reveal that microorganisms concentrate ambient manganese that becomes greatly enhanced in brown to black varnish. Specific characteristics of desert varnish and of varnish bacteria support a microbial origin for manganese-rich films. Varnish microbes can be cultured and produce laboratory manganese films. Accordingly, natural desert varnish and also manganese-rich rock varnishes in nondesert environments appear to be a product of microbial activity. PMID:17744757

  17. Microbial origin of desert varnish.

    PubMed

    Dorn, R I; Oberlander, T M

    1981-09-11

    Scanning electron microscopy and energy dispersive x-ray analyses of desert varnish reveal that microorganisms concentrate ambient manganese that becomes greatly enhanced in brown to black varnish. Specific characteristics of desert varnish and of varnish bacteria support a microbial origin for manganese-rich films. Varnish microbes can be cultured and produce laboratory manganese films. Accordingly, natural desert varnish and also manganese-rich rock varnishes in nondesert environments appear to be a product of microbial activity.

  18. OVERVIEW OF AMERICAN BRASS BUFFALO PLANT FROM ROOF OF STRAND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    OVERVIEW OF AMERICAN BRASS BUFFALO PLANT FROM ROOF OF STRAND ANNEALING TOWER, INCLUDING CASTING SHOP AND BAG HOUSE (CENTER-LEFT) AND PORTION OF REROLL BAY (R). VIEW LOOKING SOUTHWEST. - American Brass Foundry, 70 Sayre Street, Buffalo, Erie County, NY

  19. Libyan Desert, Libya, Africa

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Desert landscapes such as this part of the northern Sahara (27.0N, 11.0E) may be analogous to other planets which have no soil or plant growth. The dark rocks in this view are probably volcanic in origin and have many stream beds leading into the dune areas. These stream beds carry sediments towards the lower terrain where the water evaporates, leaving the sediments to be wind blown into the complex dune patterns. The red color comes from iron oxides.

  20. Southwest Asia assessment.

    PubMed

    Devendra, T

    1984-06-01

    Southwest Asia, which support 1/3 of the world's population, is acutely aware of the consequences of rapid and excessive population growth. No other region has consciously devoted so much of its resources to stemming excessive population growth. India, with a population of 684 million, formulated a policy of population limitation in the 1950s. The 1980 government rededicated itself to voluntary family planning and rebuilt the broad coalition of an excellent infrastructure of government institutions, voluntary organizations, and international agencies. Government support for family planning clinics began in Bangladesh in the 1960s. A strong institutional structure has been established under the supervision of the National Population Council. Innovative approaches to family planning service delivery have been initiated by an admirable array of institutions. Pakistan's Population Welfare Plan provides substantial funds and an administrative structure to make maternal/child helath care and family planning services available in rural areas. Another welfare program encourages smaller families through projects to enhance the status of women by improving literacy, establishing rural industries, and advocating late marriage. Nepal has had to struggle with a poor administrative structure, grossly insufficient medical services, and an inadequate database for policy formulation. Family planning services are now a component of the overall health program. The family planning services of the pioneer Afghan Family Guidance Association, established in 1968, have been incorported into the national maternal/child health program. The present government of Iran views foreign assistance as an unacceptable form of persuasion and has phased out all international funded family planning programs. Sri Lanka is the only country in the region to have made the demographic transition to fertility decline. An impressive health infrastructure delivers family planning services at every level using

  1. Native American Architecture.

    ERIC Educational Resources Information Center

    Nabokov, Peter; Easton, Robert

    This book presents building traditions of the major Indian tribes in nine regions of the North American continent, from the huge, plankhouse villages of the Northwest Coast, to the moundbuilder towns and temples of the Southeast, to the Navajo hogans and adobe pueblos of the Southwest. Indian buildings are a central element of Indian culture, the…

  2. Desert landscape irrigation

    SciTech Connect

    Quinones, R.

    1995-06-01

    Industrialization can take place in an arid environment if a long term, overall water management program is developed. The general rule to follow is that recharge must equal or exceed use. The main problem encountered in landscape projects is that everyone wants a lush jungle setting, tall shade trees, ferns, with a variety of floral arrangements mixed in. What we want, what we can afford, and what we get are not always the same. Vegetation that requires large quantities of water are not native to any desert. Surprisingly; there are various types of fruit trees, and vegetables that will thrive in the desert. Peaches, plums, nut trees, do well with drip irrigation as well as tomatoes. Shaded berry plans will also do well, the strawberry being one. In summary; if we match our landscape to our area, we can then design our irrigation system to maintain our landscape and grow a variety of vegetation in any arid or semiarid environment. The application of science and economics to landscaping has now come of age.

  3. Hydrologic Evaluation of the Jungo Area, Southern Desert Valley, Nevada

    USGS Publications Warehouse

    Lopes, Thomas J.

    2010-01-01

    RecologyTM, the primary San Francisco waste-disposal entity, is proposing to develop a Class 1 landfill near Jungo, Nevada. The proposal calls for the landfill to receive by rail about 20,000 tons of waste per week for up to 50 years. On September 22, 2009, the Interior Appropriation (S.A. 2494) was amended to require the U.S. Geological Survey to evaluate the proposed Jungo landfill site for: (1) potential water-quality impacts on nearby surface-water resources, including Rye Patch Reservoir and the Humboldt River; (2) potential impacts on municipal water resources of Winnemucca, Nevada; (3) locations and altitudes of aquifers; (4) how long it will take waste seepage from the site to contaminate local aquifers; and (5) the direction and distance that contaminated groundwater would travel at 95 and 190 years. This evaluation was based on review of existing data and information. Desert Valley is tributary to the Black Rock Desert via the Quinn River in northern Desert Valley. The Humboldt River and Rye Patch Reservoir would not be affected by surface releases from the proposed Jungo landfill site because they are in the Humboldt basin. Winnemucca, on the Humboldt River, is 30 miles east of the Jungo landfill site and in the Humboldt basin. Groundwater-flow directions indicate that subsurface flow near the proposed Jungo landfill site is toward the south-southwest. Therefore, municipal water resources of Winnemucca would not be affected by surface or subsurface releases from the proposed Jungo landfill site. Basin-fill aquifers underlie the 680-square-mile valley floor in Desert Valley. Altitudes around the proposed Jungo landfill site range from 4,162 to 4,175 feet. Depth to groundwater is fairly shallow in southern Desert Valley and is about 60 feet below land surface at the proposed Jungo landfill site. A groundwater divide exists about 7 miles north of the proposed Jungo landfill site. Groundwater north of the divide flows north towards the Quinn River. South of

  4. Bilingualism in the Southwest.

    ERIC Educational Resources Information Center

    Turner, Paul R., Ed.

    This book is intended to encourage interdisciplinary exchange of ideas and cooperation in the study of bilingualism. To this end, those who contributed the articles collected here belong to several disciplines: anthropology, education, English, linguistics, sociology and Spanish. The book is divided into three parts: (1) Mexican-Americans, (2)…

  5. A Microscopists View of Desert Varnish from the Sonoran Desert

    NASA Astrophysics Data System (ADS)

    Garvie, L. A. J.; Burt, D. M.; Buseck, P. R.

    2009-03-01

    Nanometer-scale element mapping and spectroscopy of desert varnish reveals a dynamic disequilibrium system characterized by post-depositional mineralogical, chemical, and structural changes, activated by liquid water.

  6. Design and fabrication of a prototype system for photovoltaic residences in the Southwest

    NASA Astrophysics Data System (ADS)

    1982-06-01

    Described are the design of a photovoltaic powered residence for the American Southwest, dubbed Casa fotovoltaica, and the construction of a prototype building at the Southwest Residential Experiment Station for testing the performance of the full size photovoltaic (PV) system. Included are architectural drawings of both the residence and the prototype, analysis of the energy requirements of the residence, prediction of PV system output, description of the electrical system, and history of the construction process of the prototype.

  7. Challenge of a desert: revegetation of disturbed desert lands

    SciTech Connect

    Wallace, A.; Romney, E.M.; Hunter, R.B.

    1980-01-01

    The revegetation of disturbed, arid lands is one of the great challenges of a desert. An attempt to encourage it is not an impossible task, however, if the natural and the man-made resources available are utilized and managed. Where rainfall and temperature conditions approach or exceed those of the Great Basin desert, restoration of disturbed land will occur through natural revegetation processes within a reasonable period of time. This is not generally the case in the more arid Mojave Desert areas where the moisture and temperature conditions are less favorable for germination and seedling survival. Restoration of vegetation by natural reseeding can, however, occur within local sites where moisture has concentrated as the result of terrain features forming catchment basins. Otherwise, the natural revegetation processes in the Mojave Desert areas require much longer periods of time (possibly decades or centuries) than are practical for meeting environmental protection standards imposed by current legislation. Through better understanding of the processes governing revegetation and the ability to control them, it is possible for man to more rapidly restore disturbed desert lands. Terrain manipulation to form moisture catchment basins, selection of seed from pioneering shrub species, preservation of existing shrub clump fertile islands in the soil, supplemental fertilization, irrigation, organic amendments, and transplanting vigorous shrub species are some of the important things that can be done to help restore disturbed desert land.

  8. Desert tortoise hibernation: Temperatures, timing, and environment

    USGS Publications Warehouse

    Nussear, K.E.; Esque, T.C.; Haines, D.F.; Tracy, C.R.

    2007-01-01

    This research examined the onset, duration, and termination of hibernation in Desert Tortoises (Gopherus agassizii) over several years at multiple sites in the northeastern part of their geographic range, and recorded the temperatures experienced by tortoises during winter hibernation. The timing of hibernation by Desert Tortoises differed among sites and years. Environmental cues acting over the short-term did not appear to influence the timing of the hibernation period. Different individual tortoises entered hibernation over as many as 44 days in the fall and emerged from hibernation over as many as 49 days in the spring. This range of variation in the timing of hibernation indicates a weak influence at best of exogenous cues hypothesized to trigger and terminate hibernation. There do appear to be regional trends in hibernation behavior as hibernation tended to begin earlier and continue longer at sites that were higher in elevation and generally cooler. The emergence date was generally more similar among study sites than the date of onset. While the climate and the subsequent timing of hibernation differed among sites, the average temperatures experienced by tortoises while hibernating differed by only about five degrees from the coldest site to the warmest site. ?? 2007 by the American Society of Ichthyologists and Herpetologists.

  9. 4. Historic American Buildings Survey, Bill Engdahl for HedrichBlessing, Photographers, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey, Bill Engdahl for Hedrich-Blessing, Photographers, February, 1979 SOUTHWEST ELEVATION. - Field-Pacheco Complex, 1049 East Monroe Street, Brownsville, Cameron County, TX

  10. 3. Historic American Buildings Survey Ray Malinowski, Photographer JulyAugust 1968 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Ray Malinowski, Photographer July-August 1968 SOUTHWEST VIEW - Louisville & Nashville Railroad, Marine Terminal, 207 East Main Street, Pensacola, Escambia County, FL

  11. 2. Historic American Buildings Survey, Bill Engdahl for HedrichBlessing, Photographers, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey, Bill Engdahl for Hedrich-Blessing, Photographers, February, 1979 VIEW FROM SOUTHWEST. - Cameron County Courthouse, 1150 East Madison Street, Brownsville, Cameron County, TX

  12. 3. Historic American Buildings Survey, Bill Engdahl for HedrichBlessing, Photographers, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey, Bill Engdahl for Hedrich-Blessing, Photographers, February, 1979 SOUTHWEST ELEVATION. - Cameron County Courthouse, 1150 East Madison Street, Brownsville, Cameron County, TX

  13. 3. Historic American Buildings Survey, Bill Engdahl for HedrichBlessing, Photographers, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey, Bill Engdahl for Hedrich-Blessing, Photographers, February, 1979 SOUTHWEST (FRONT) ELEVATION. - Douglas Drug Store, 1201 East Elizabeth Street, Brownsville, Cameron County, TX

  14. Vegetation Structure and Function along Ephemeral Streams in the Sonoran Desert

    NASA Astrophysics Data System (ADS)

    Stromberg, J. C.; Katz, G.

    2011-12-01

    Despite being the most prevalent stream type in the American Southwest, far less is known about riparian ecosystems associated with ephemeral streams than with perennial streams. Patterns of plant composition and structure reflect complex environmental gradients, including water availability and flood intensity, which in turn are related to position in the stream network. A survey of washes in the Sonoran Desert near Tucson, Arizona showed species composition of small ephemeral washes to be comprised largely of upland species, including large seeded shrubs such as Acacia spp. and Larrea tridentata. Small seeded disturbance adapted xerophytic shrubs, such as Baccharis sarothroides, Hymenoclea monogyra and Isocoma tenuisecta, were common lower in the stream network on the larger streams that have greater scouring forces. Because ephemeral streams have multiple water sources, including deep (sometimes perched) water tables and seasonally variable rain and flood pulses, multiple plant functional types co-exist within a stream segment. Deep-rooted phreatophytes, including Tamarix and nitrogen-fixing Prosopis, are common on many washes. Such plants are able to access not only water, but also pools of nutrients, several meters below ground thereby affecting nutrient levels and soil moisture content in various soil strata. In addition to the perennial plants, many opportunistic and shallow-rooted annual species establish during the bimodal wet seasons. Collectively, wash vegetation serves to stabilize channel substrates and promote accumulation of fine sediments and organic matter. In addition to the many streams that are ephemeral over their length, ephemeral reaches also occupy extensive sections of interrupted perennial rivers. The differences in hydrologic conditions that occur over the length of interrupted perennial rivers influence plant species diversity and variability through time. In one study of three interrupted perennial rivers, patterns of herbaceous species

  15. Mate desertion in the snail kite

    USGS Publications Warehouse

    Beissinger, S.R.; Snyder, N.F.R.

    1988-01-01

    Mate desertion during the breeding cycle was documented at 28 of 36 (78%) snail kite, Rostrhamus sociabilis nests in Florida between 1979 and 1983. Offspring mortality occurred at only one deserted nest, however. Parents that were deserted by their mates continued to care for their young until independence (3?5 additional weeks) and provided snails at a rate similar to that of both parents combined before desertion. Males and females deserted with nearly equal frequency, except in 1982 when more females deserted. No desertion occurred during drought years, whereas desertion occurred at nearly every nest during favourable conditions. The occurrence of mate desertion was generally related to indirect measures of snail abundance: foraging range, snail delivery rates to the young and growth rates. Small broods were deserted more frequently by females than by males and tended to be deserted earlier than large ones. After desertion, deserters had the opportunity to re-mate and nest again since breeding seasons were commonly lengthy, but whether they did so was impossible to determine conclusively in most cases. The deserted bird sometimes incurred increased energetic costs and lost breeding opportunities during periods of monoparental care.

  16. Thermodynamic and pedogenic differences between desert microsites

    NASA Astrophysics Data System (ADS)

    Young, Michael; Caldwell, Todd; Lin, Henry

    2014-05-01

    taken along transects radiating from canopies of perennial shrubs into bare interspaces of structured soils. We augmented these measurements with ground-penetrating radar (GPR), laboratory analyses, and (in some cases) soil trenches. The results showed higher saturated conductivity under canopies versus interspaces, regardless of surface age, with the largest differences observed on older, developed soils. Bulk density, soil structure grade, and silt and clay content increased significantly away from the canopy, and organic content decreased toward interspaces. Trends in soil properties, from canopies to interspaces, were found to be predictable to a distance of 1.35 +/- 0.32 times the canopy radius, regardless of the size or genus of the shrub. The microsite environments, which are separated by only 10s of cm, release energy and mass at different rates—the fluxes differ by microsite locations. They exist with different thermodynamic gradients, with larger upward fluxes to support shrubs under canopy microsites and larger downward fluxes in interspaces. Armoured against change in interspaces can explain progressive structural evolution of pedons, a paradoxically reduced water infiltration capacity, and a contraction of canopy volumes and ecosystem production in older soils. We use these gradients to illustrate the importance of microsite location when considering complex feedbacks that result through currently-observed, time-dependent processes of pedogenesis in arid regions of the desert southwest.

  17. Ecological controls on water-cycle response to climate variability in deserts

    PubMed Central

    Scanlon, B. R.; Levitt, D. G.; Reedy, R. C.; Keese, K. E.; Sully, M. J.

    2005-01-01

    The impact of climate variability on the water cycle in desert ecosystems is controlled by biospheric feedback at interannual to millennial timescales. This paper describes a unique field dataset from weighing lysimeters beneath nonvegetated and vegetated systems that unequivocally demonstrates the role of vegetation dynamics in controlling water cycle response to interannual climate variability related to El Niño southern oscillation in the Mojave Desert. Extreme El Niño winter precipitation (2.3-2.5 times normal) typical of the U.S. Southwest would be expected to increase groundwater recharge, which is critical for water resources in semiarid and arid regions. However, lysimeter data indicate that rapid increases in vegetation productivity in response to elevated winter precipitation reduced soil water storage to half of that in a nonvegetated lysimeter, thereby precluding deep drainage below the root zone that would otherwise result in groundwater recharge. Vegetation dynamics have been controlling the water cycle in interdrainage desert areas throughout the U.S. Southwest, maintaining dry soil conditions and upward soil water flow since the last glacial period (10,000-15,000 yr ago), as shown by soil water chloride accumulations. Although measurements are specific to the U.S. Southwest, correlations between satellite-based vegetation productivity and elevated precipitation related to El Niño southern oscillation indicate this model may be applicable to desert basins globally. Understanding the two-way coupling between vegetation dynamics and the water cycle is critical for predicting how climate variability influences hydrology and water resources in water-limited landscapes. PMID:15837922

  18. Ecological controls on water-cycle response to climate variability in deserts.

    PubMed

    Scanlon, B R; Levitt, D G; Reedy, R C; Keese, K E; Sully, M J

    2005-04-26

    The impact of climate variability on the water cycle in desert ecosystems is controlled by biospheric feedback at interannual to millennial timescales. This paper describes a unique field dataset from weighing lysimeters beneath nonvegetated and vegetated systems that unequivocally demonstrates the role of vegetation dynamics in controlling water cycle response to interannual climate variability related to El Nino southern oscillation in the Mojave Desert. Extreme El Nino winter precipitation (2.3-2.5 times normal) typical of the U.S. Southwest would be expected to increase groundwater recharge, which is critical for water resources in semiarid and arid regions. However, lysimeter data indicate that rapid increases in vegetation productivity in response to elevated winter precipitation reduced soil water storage to half of that in a nonvegetated lysimeter, thereby precluding deep drainage below the root zone that would otherwise result in groundwater recharge. Vegetation dynamics have been controlling the water cycle in interdrainage desert areas throughout the U.S. Southwest, maintaining dry soil conditions and upward soil water flow since the last glacial period (10,000-15,000 yr ago), as shown by soil water chloride accumulations. Although measurements are specific to the U.S. Southwest, correlations between satellite-based vegetation productivity and elevated precipitation related to El Nino southern oscillation indicate this model may be applicable to desert basins globally. Understanding the two-way coupling between vegetation dynamics and the water cycle is critical for predicting how climate variability influences hydrology and water resources in water-limited landscapes. PMID:15837922

  19. Southwest Airlines: lessons in loyalty.

    PubMed

    D'Aurizio, Patricia

    2008-01-01

    Southwest Airlines continues to garner accolades in the areas of customer service, workforce management, and profitability. Since both the health care and airlines industries deal with a service rather than a product, the customer experience depends on the people who deliver that experience. Employees' commitment or "loyalty" to their customers, their employer, and their work translates into millions of dollars of revenue. What employee wants to work for "the worst employer in town?" Nine loyalty lessons from Southwest can be carried over to the health care setting for the benefit of employees and patients. PMID:19330974

  20. Analysis of tectonic features in US southwest from Skylab photographs

    NASA Technical Reports Server (NTRS)

    Abdel-Gawad, M. (Principal Investigator); Tubbesing, L.

    1975-01-01

    The author has identified the following significant results. Skylab photographs were utilized to study faults and tectonic lines in selected areas of the U.S. Southwest. Emphasis was on elements of the Texas Zone in the Mojave Desert and the tectonic intersection in southern Nevada. Transverse faults believed to represent the continuation of the Texas Zone were found to be anomalous in strike. This suggests that the Mojave Desert block was rotated counterclockwise as a unit with the Sierra Nevada. Left-lateral strike-slip faults in Lake Mead area are interpreted as elements of the Wasatch tectonic zone; their anomalous trend indicates that the Lake Mead area has rotated clockwise with the Colorado Plateau. A tectonic model relating major fault zones to fragmentation and rotation of crustal blocks was developed. Detailed correlation of the high resolution S190B metric camera photographs with U-2 photographs and geologic maps demonstrates the feasibility of utilizing S190B photographs for the identification of geomorphic features associated with recent and active faults and for the assessment of seismic hazards.

  1. Variations in ADH and ALDH in Southwest California Indians

    PubMed Central

    Ehlers, Cindy L.

    2007-01-01

    Native Americans as a group have the highest rates of alcohol-related deaths of all ethnicities in the United States; however, it remains unclear how and why a greater proportion of individuals in some Native American communities develop alcohol-related problems and alcohol use disorders (AUDs). One potential factor that can influence responses to alcohol are variations in alcohol-metabolizing enzymes. Researchers have analyzed the frequencies of variants in the alcohol-metabolizing enzymes alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) in some Native American populations. So far the studies have yielded no evidence that an ALDH2 variant, which has shown protective effects in other populations, is found in either American Indians or Alaska Natives. A variant of the ALDH1 enzyme that is encoded by the ALDH1A1*2 allele, however, was found in a small proportion of a group of Southwest California Indians and had a protective effect against alcoholism in that population. Furthermore, a variant of the ADH1B enzyme that is encoded by the ADH1B*3 allele was found in a similar proportion of Southwest California Indians and also was associated with a protective effect. However, these findings do not explain the high prevalence of alcoholism in the tribes investigated. PMID:17718395

  2. 2. Historic American Buildings Survey Nathaniel R. Ewan, Photographer July ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Nathaniel R. Ewan, Photographer July 12, 1936 EXTERIOR - BLAST FURNACE - WEST ELEVATION - CLOSE-UP - The Deserted Village, Blast Furnace, Allaire, Monmouth County, NJ

  3. Phytoremediation for Oily Desert Soils

    NASA Astrophysics Data System (ADS)

    Radwan, Samir

    This chapter deals with strategies for cleaning oily desert soils through rhizosphere technology. Bioremediation involves two major approaches; seeding with suitable microorganisms and fertilization with microbial growth enhancing materials. Raising suitable crops in oil-polluted desert soils fulfills both objectives. The rhizosphere of many legume and non-legume plants is richer in oil-utilizing micro-organisms than non-vegetated soils. Furthermore, these rhizospheres also harbour symbiotic and asymbiotic nitrogen-fixing bacteria, and are rich in simple organic compounds exuded by plant roots. Those exudates are excellent nutrients for oil-utilizing microorganisms. Since many rhizospheric bacteria have the combined activities of hydrocarbon-utilization and nitrogen fixation, phytoremediation provides a feasible and environmentally friendly biotechnology for cleaning oil-polluted soils, especially nitrogen-poor desert soils.

  4. [Water and environment in the Southwest of Madagascar].

    PubMed

    Razanamparany, L

    1993-04-01

    The dry and arid southwest region of Madagascar is not a desert but resembles the Sahel region of West Africa. The chronic water deficit is aggravated by the heat and constant winds that accelerate evapotranspiration on the permeable soils. The dryness occurs because the southwest region lies outside the main pluviogenic systems. Erosion occurs at all seasons. In the winter the sun and winds are the main causes, while the rare storms are more conducive to run-off and to erosion than to absorption. The acute water shortage in the southwest has prompted hydrogeologic research and well-drilling, but the high salt content of the water and other impurities will be a limiting factor for development of the area. The population of the southwest is extremely mobile. Human settlements are concentrated in the valleys and depressions and along major roads. Customary rights to land under the control of the traditional chiefs regulate tenure in most areas. But especially in the river bottoms, the coming of cash crops cultivated with modern equipment has resulted in significant erosion which has aggravated ecological problems. Accelerating soil degradation has led peasants to extend their lands under cultivation to the detriment of forest cover. Cattle herding remains the principal economic activity in the southwest. Herding has progressed from nomadism to pastoralism, but it remains a sign of power and wealth. Transhumance is the strategy of herders faced with shortages of water and pasturage, demographic pressure, and environmental degradation. Raising of sheep and goats constitutes a supplemental food source, medium of exchange, and form of savings. But angora goats graze on everything in their path, devastating their surrounds. Fear of cattle thefts militates against efforts to improve the quality of the stock. The various problems together have prompted a wasteful exploitation of the forest resources. Development strategies for the area explored by the government have all

  5. Shaking up the future of Hispanic students in rural southwest Arizona: A collaborative research/teaching effort creating a bridge between students and the geosciences.

    NASA Astrophysics Data System (ADS)

    Conway, M. F.; Croxen, F.; Garrett, M.

    2002-12-01

    Arizona Western College, Yuma, Arizona, serves the largely Hispanic population of rural southwestern Arizona. The majority of our students are first-generation college students who frequently lack strong educational role models. We are constructing a geoscience education program for recruiting and mentoring Hispanic and Native American students from Yuma and La Paz counties, Arizona. This program will be structured around faculty-mentored, undergraduate research on the seismicity and related geologic phenomenon of the Salton Trough of southeastern California and northern Mexico. Yuma-area students are well-suited for this program, because they have strong footholds in the cultures and languages of the region. Our chief goal is to provide educational opportunities in geoscience for historically underrepresented minorities of southern Arizona and California. Ultimately, this should lead to leadership roles in the geoscience for Hispanics in the largely Hispanic communities of the desert southwest. Importantly, this geoscience education program has the support and collaboration of science educators from across the educational spectrum in southern Arizona and California, and northern Mexico.

  6. Cultural Arts in the Southwest.

    ERIC Educational Resources Information Center

    Cross, Kate

    1998-01-01

    Presents a pottery project for eighth-grade students based on a study of ancient and modern forms of Pueblo Indian pottery of the Southwest United States. Details the process for creating either carved, red clay, or painted white clay pottery typical of these cultural groups. Relates student reactions to the project. (DSK)

  7. Native Art of the Southwest.

    ERIC Educational Resources Information Center

    Langham, Barbara A.

    1997-01-01

    Provides historical information on native Southwest peoples and their arts to encourage appreciation and understanding of this cultural heritage. Provides instructions and supply lists for age-appropriate craft projects including woven baskets and rugs, clay pots, clay and paper beads, silver bracelets, kachina dolls, sand paintings, dream…

  8. The Influence of Race and Ethnicity on Substance Use and Negative Activity Involvement among Monoracial and Multiracial Adolescents of the Southwest

    ERIC Educational Resources Information Center

    Jackson, Kelly F.; LeCroy, Craig W.

    2009-01-01

    This study examined predictors of substance use and negative activity involvement among a diverse sample of European American, African American, Hispanic, Native American, and multiracial early adolescents (n = 749) living in a large urban city in the Southwest United States. This study investigated a broad set of predictor variables that tap…

  9. Borders of Loss: The Representation of a Desert City in Two Chicano Testimonial Texts

    ERIC Educational Resources Information Center

    Vasquez, Mary S.

    2007-01-01

    Diego Vazquez Jr.'s novel "Growing Through the Ugly" (1997) and Gloria Lopez-Stafford's memoir of childhood "A Place in El Paso: A Mexican American Childhood" (1996) offer two divergent views of the west Texas city and its surrounding desert. In the vision created in the Vazquez text, El Paso is a site of exploitation, predation, and a limitless,…

  10. Snails, stable iostopes, and southwestern desert paleoclimates

    SciTech Connect

    Sharpe, S.E.; Whelan, J.F.; Forester, R.M.; Burdett, J.

    1995-09-01

    Modern and fossil molluscs (snails) occur in many localities in and semi-arid regions throughout the desert southwest. Live terrestrial snails are found under rocks and in forest litter and aquatic taxa inhabit springs, seeps, and/or wetlands. Molluscs uptake local water during their growing season (spring and summer) and incorporate its delta 180 signature into their shells. Preliminary 180 analysis of modem shells from the southern Great Basin indicates that the shells probably reflect meteoric water 180 values during the growing season. This provides a way to estimate the delta 180 value of precipitation and, thereby, the source of the moisture-bearing air masses. Significant 180 variability in shells analyzed include geographic location, elevation, taxonomy, and habitat (terrestrial, spring, or wetland). We found a rough inverse correlation with elevation in modem shells from the Spring Range in southern Nevada. The delta 180 values of modem and fossil shells are also very different; modem values in this location are much higher than those from nearby late Pleistocene-age molluscs suggesting that the Pleistocene summers were variously colder and wetter than today or less evaporative (more humid). Assuming shell material directly reflects the 180 of the growing-season environment, comparison of modem and fossil shell delta 180 values can potentially identify changes in air-mass moisture sources and can help to define seasonal precipitation change through time. Comprehension and quantification of community and isotopic variability in modem gastropods is required to create probabilistic valid transfer functions with fossil materials. Valid inferences about past environmental conditions can then be established with known confidence limits.

  11. Food insecurity and food deserts.

    PubMed

    Camp, Nadine L

    2015-08-15

    Food insecurity has been steadily increasing in the United States with prevalence at nearly 15% of all households. Nurse practitioners can assess for food insecurity and provide local resources for families living in neighborhoods without easy access to healthy foods, otherwise known as food deserts.

  12. On a Crowded Desert Island.

    ERIC Educational Resources Information Center

    Rothstein, Samuel

    1989-01-01

    Suggests reference sources most appropriate for a desert island. In addition to "Robinson Crusoe" (Daniel Defoe) and a reference guide to the literature of travel, the list includes basic books on reference work, guides to reference sources, journals, an almanac, encyclopedias, a guide to English usage, and a book of quotations. (14 references)…

  13. Desert Pathfinder at Work

    NASA Astrophysics Data System (ADS)

    2005-09-01

    The Atacama Pathfinder Experiment (APEX) project celebrates the inauguration of its outstanding 12-m telescope, located on the 5100m high Chajnantor plateau in the Atacama Desert (Chile). The APEX telescope, designed to work at sub-millimetre wavelengths, in the 0.2 to 1.5 mm range, passed successfully its Science Verification phase in July, and since then is performing regular science observations. This new front-line facility provides access to the "Cold Universe" with unprecedented sensitivity and image quality. After months of careful efforts to set up the telescope to work at the best possible technical level, those involved in the project are looking with satisfaction at the fruit of their labour: APEX is not only fully operational, it has already provided important scientific results. "The superb sensitivity of our detectors together with the excellence of the site allow fantastic observations that would not be possible with any other telescope in the world," said Karl Menten, Director of the group for Millimeter and Sub-Millimeter Astronomy at the Max-Planck-Institute for Radio Astronomy (MPIfR) and Principal Investigator of the APEX project. ESO PR Photo 30/05 ESO PR Photo 30/05 Sub-Millimetre Image of a Stellar Cradle [Preview - JPEG: 400 x 627 pix - 200k] [Normal - JPEG: 800 x 1254 pix - 503k] [Full Res - JPEG: 1539 x 2413 pix - 1.3M] Caption: ESO PR Photo 30/05 is an image of the giant molecular cloud G327 taken with APEX. More than 5000 spectra were taken in the J=3-2 line of the carbon monoxide molecule (CO), one of the best tracers of molecular clouds, in which star formation takes place. The bright peak in the north of the cloud is an evolved star forming region, where the gas is heated by a cluster of new stars. The most interesting region in the image is totally inconspicuous in CO: the G327 hot core, as seen in methanol contours. It is a truly exceptional source, and is one of the richest sources of emission from complex organic molecules in the

  14. Water balance in desert Drosophila: lessons from non-charismatic microfauna.

    PubMed

    Gibbs, Allen G

    2002-11-01

    Water stress is a particularly important problem for insects and other small organisms in arid environments. Cactophilic fruit flies in the genus Drosophila have invaded deserts on numerous occasions, including multiple independent invasions of North American deserts. Because the evolutionary history of this genus is so well studied, we can investigate the mechanisms of adaptation in a rigorous phylogenetic context. As expected, desert fruit flies lose water less rapidly than their mesic congeners. They are also able to tolerate the loss of a greater percentage of body water, but this difference is mainly due to phylogenetic history, and does not represent an adaptation specifically to desert habitats. A laboratory analogue of desert Drosophila is provided by populations of D. melanogaster that have been subjected to selection for desiccation resistance. Selected populations resemble desert species in that they lose water slowly, relative to control populations, and are not more tolerant of dehydration stress. They differ, however, in having much higher water contents and different behavioral responses to desiccating conditions. Our comparisons of laboratory and natural populations reveal that not all possible adaptive mechanisms evolve in stressful environments. Different physiological and behavioral strategies may evolve depending upon the particular options available in the environment.

  15. Cenozoic reconstruction of southwest Pacific

    SciTech Connect

    Chun, Y.Y.; Kroenke, L.W.

    1986-07-01

    Poles of opening and spreading rates for some of the well-studied marginal basins in the southwest Pacific have been redetermined. Times of opening range from Late Cretaceous-Paleocene in the Tasman basin to middle Pliocene in the Bismarck Sea. The observed magnetic lineations in most of these basins show a relatively short duration of opening and relatively small area of total opening. Most of the smaller basins are bounded by troughs and arcuate island chains, some of which are inferred to be trenches and volcanic arcs situated along paleoconvergent boundaries. At least four successive paleoconvergent boundaries are believed to have formed between the Pacific and the Indian-Australian plates during the Cenozoic. Combining the newly determined poles of opening, spreading rates, and paleoplate boundary locations, a series of palinspastic maps of the southwest Pacific have been constructed for these times, relative to a fixed hot-spot frame of reference for both the Pacific and Indian-Australian plates.

  16. Understanding the effects of global change on ecosystems of the Sonoran Desert

    SciTech Connect

    Halvorson, W.L. )

    1993-06-01

    The Global Change program for the Sonoran Desert just began in March 1992. Currently, two projects are being directly funded by the National Park Service and we are coordinating with research of other agencies. One thrust of the program is to understand the effect of climate on species growth, abundances and distribution. This will be done using a number of methods. One is growth ring analysis of conifers on mountain ranges in and bordering the Sonoran Desert. Another study will relate the USGS Desert Laboratory data base on plant species distributions to a mesoscale climate model. Other programs that we are coordinating with include a USGS Desert Laboratory project to study long term changes in plant communities of the southwest using a comparison of photos from the early 1930s, early 1960s and early 1990s. Other agencies have active global climate research at The University of Arizona and we are working to coordinate the NPS program with these at the investigator level through participation in a university-wide Global Change Committee.

  17. 6. Historic American Buildings Survey John O. Brostrup, Photographer September ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey John O. Brostrup, Photographer September 17, 1936 VIEW FROM NORTHEAST (front) - Wheat Row, 1315-1321 Fourth Street Southwest, Washington, District of Columbia, DC

  18. 1. Historic American Buildings Survey John O. Brostrup, Photographer December ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey John O. Brostrup, Photographer December 29, 1936 10:45 A. M. DETAIL OF MANTEL, 1321 HOUSE, SECOND FLOOR FRONT ROOM NORTH WALL - Wheat Row, 1321 Fourth Street Southwest, Washington, District of Columbia, DC

  19. 1. Historic American Buildings Survey John O. Brostrup, Photographer September ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey John O. Brostrup, Photographer September 17, 1936 10:45 A. M. VIEW OF 1315 4th St., S. W., FROM NORTHEAST (front) - Wheat Row, 1315 Fourth Street Southwest, Washington, District of Columbia, DC

  20. 112. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. April ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    112. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. April 24, 1940. MEDALLION - 'ST. AGNES OF PRAGUE'. NICHE - 'BLESSED BERNADINA FELTRIA'. (SOUTHWEST ELEVATION). EAST TRANSEPT - San Xavier del Bac Mission, Mission Road, Tucson, Pima County, AZ

  1. 1. Historic American Buildings Survey John O. Brostrup, Photographer May ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey John O. Brostrup, Photographer May 12, 1936 11:25 A.M. VIEW FROM SOUTHWEST (front) - Christ Church at Accokeek, 600 West Farmington Road, Accokeek, Prince George's County, MD

  2. 1. Historic American Buildings Survey John O. Brostrup, photographer May ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey John O. Brostrup, photographer May 21, 1936 9:45 A.M. ONE-HALF VIEW FROM SOUTHWEST (Front) - Forest Hill, 4310 Enterprise Road (State Route 556), Buena Vista, Prince George's County, MD

  3. 2. Historic American Buildings Survey John O. Brostrup, photographer May ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey John O. Brostrup, photographer May 21, 1936 9:50 A.M. ONE-HALF VIEW FROM SOUTHWEST (Front) - Forest Hill, 4310 Enterprise Road (State Route 556), Buena Vista, Prince George's County, MD

  4. 11. Historic American Buildings Survey Elmer R. Pearson, Photographer 1969 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Historic American Buildings Survey Elmer R. Pearson, Photographer 1969 LOOKING SOUTHWEST - Sabbathday Lake Shaker Community Meetinghouse, West of State Route 26, South of North Raymond Road, northwest edge of church family area, Sabbathday Lake Village, Cumberland County, ME

  5. 2. Historic American Buildings Survey John O. Brostrup, Photographer March ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey John O. Brostrup, Photographer March 4, 1937 1:45 P.M. VIEW FROM SOUTHWEST (front). - National Zoological Park, Holt House, Adams Mill Road Vicinity, Washington, District of Columbia, DC

  6. 26. Historic American Buildings Survey E. R. Pearson, Photographer 1972 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. Historic American Buildings Survey E. R. Pearson, Photographer 1972 STAIRS IN FIRST ATTIC HALL TO SECOND ATTIC, LOOKING SOUTHWEST - Shaker Centre Family Dwelling House, West side of U.S. Route 68, South Union, Logan County, KY

  7. 3. Historic American Buildings Survey Cervin Robinson, Photographer January 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Cervin Robinson, Photographer January 1959 SOUTHWEST ENTRANCE, SOUTHEAST SIDE - Massachusetts Charitable Mechanics Association, Exhibition Hall, Huntington Avenue & West Newton Street, Boston, Suffolk County, MA

  8. 1. Historic American Buildings Survey Frederick A. Eastman, Photographer January ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Frederick A. Eastman, Photographer January 1938 GENERAL VIEW FROM STREET - SOUTHWEST - Ballantyne Robinson House, Military Plaza (141 South Fifth Avenue), Tucson, Pima County, AZ

  9. 11. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. April ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. April 10, 1940 GENERAL VIEW MAIN CHURCH (SOUTHWEST ELEVATION). - San Xavier del Bac Mission, Mission Road, Tucson, Pima County, AZ

  10. 8. Historic American Buildings Survey John O. Brostrup, Photographer March ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Historic American Buildings Survey John O. Brostrup, Photographer March 22, 1937 9:40 A.M. VIEW FROM SOUTHWEST (front). - Timothy Caldwell House, 2017 "Eye" Street Northwest, Washington, District of Columbia, DC

  11. 16. Historic American Buildings Survey, Cervin Robinson, Photographer August, 1958 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. Historic American Buildings Survey, Cervin Robinson, Photographer August, 1958 DOORWAYS, NORTHWEST TO SOUTHWEST ROOMS, SECOND FLOOR. - Henry Fisher House, State Route 622 (Oley Township), Yellow House, Berks County, PA

  12. 6. Historic American Buildings Survey, Cervin Robinson, Photographer August, 1958 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey, Cervin Robinson, Photographer August, 1958 EAST WALL OF SOUTHWEST ROOM, FIRST FLOOR. - Henry Fisher House, State Route 622 (Oley Township), Yellow House, Berks County, PA

  13. 15. Historic American Buildings Survey, Cervin Robinson, Photographer August, 1958 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Historic American Buildings Survey, Cervin Robinson, Photographer August, 1958 EAST WALL, SOUTHWEST ROOM, SECOND FLOOR. - Henry Fisher House, State Route 622 (Oley Township), Yellow House, Berks County, PA

  14. 1. HISTORIC AMERICAN BUILDINGS SURVEY JOHN R. KELLEY PHOTOGRAPHER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. HISTORIC AMERICAN BUILDINGS SURVEY JOHN R. KELLEY - PHOTOGRAPHER - MARCH 16, 1934 GENERAL VIEW FROM SOUTHWEST - Whitewater Canal Aqueduct, Spanning Duck Creek, Whitewater Canal (carried over creek) (Changed from Duck Creek), Metamora, Franklin County, IN

  15. 2. Historic American Buildings Survey Lester Jones, Photographer. October 1, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Lester Jones, Photographer. October 1, 1940. VIEW FROM SOUTHWEST - Fort de Chartres, Powder Magazine, Fort de Chartres State Park, Prairie du Rocher, Randolph County, IL

  16. 3. Historic American Buildings Survey, William F. Winter, Jr., Photographer, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey, William F. Winter, Jr., Photographer, April 1925, VIEW FROM SOUTHWEST, Gift of New York State Department of Education. - Shaker Church Family Sisters' Workshop, Watervliet Shaker Road, Colonie Township, Watervliet, Albany County, NY

  17. 3. Historic American Buildings Survey, William F. Winter, Jr., Photographer, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey, William F. Winter, Jr., Photographer, April 1926, VIEW FROM SOUTHWEST, Gift of New York State Department of Education. - Shaker Church Family Brethren's Workshop, Watervliet Shaker Road, Colonie Township, Watervliet, Albany County, NY

  18. 4. Historic American Buildings Survey, William F. Winter, Jr., Photographer, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey, William F. Winter, Jr., Photographer, April 1925, VIEW FROM SOUTHWEST, Gift of New York State Department of Education. - Shaker Church Family Brethren's Workshop, Watervliet Shaker Road, Colonie Township, Watervliet, Albany County, NY

  19. 1. Historic American Buildings Survey, William F. Winter, Jr., Photographer, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, William F. Winter, Jr., Photographer, September 1926, VIEW FROM SOUTHWEST, Gift of New York State Department of Education. - Shaker Church Family Seed House, Watervliet Shaker Road, Colonie Township, Watervliet, Albany County, NY

  20. 19. Historic American Buildings Survey, John O. Brostrup, Photographer November ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Historic American Buildings Survey, John O. Brostrup, Photographer November 4, 1937 1:40 P.M. VIEW OF SOUTHWEST CORNER OF SPINNING ROOM ON THIRD FLOOR OF SARON. - The Cloisters, Saron, Ephrata, Lancaster County, PA

  1. 14. Historic American Buildings Survey John O. Brostrup, Photographer April ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Historic American Buildings Survey John O. Brostrup, Photographer April 6, 1936 11:45 A. M. VIEW FROM WEST (front) - Thomas Law House, 1252 Sixth Street Southwest, Washington, District of Columbia, DC

  2. 16. Historic American Buildings Survey John O. Brostrup, Photographer March ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. Historic American Buildings Survey John O. Brostrup, Photographer March 2, 1937 10:00 A. M. DETAIL OF CORNICE. - Thomas Law House, 1252 Sixth Street Southwest, Washington, District of Columbia, DC

  3. 1. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, 1934 VIEW FROM SOUTHWEST - Second & Gabourie Streets (Old Stone House), Corner of Second & Gabourie Streets, Sainte Genevieve, Ste. Genevieve County, MO

  4. 2. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, 1934 DETAIL OF STONEWORK (SOUTHWEST CORNER) - Second & Gabourie Streets (Old Stone House), Corner of Second & Gabourie Streets, Sainte Genevieve, Ste. Genevieve County, MO

  5. 205. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. April ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    205. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. April 10, 1940. LIONS and COLUMNS, HILL OF THE CROSS (SOUTHWEST ELEVATION). - San Xavier del Bac Mission, Mission Road, Tucson, Pima County, AZ

  6. 53. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. March ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    53. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. March 24, 1940. THE CIMBORIO, PARAPETS, LIONS, FINIALS. (SOUTHWEST ELEVATION) - San Xavier del Bac Mission, Mission Road, Tucson, Pima County, AZ

  7. 1. Historic American Buildings Survey Robert W. Kerrigan, Photographer Year ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Robert W. Kerrigan, Photographer Year Built: 1846 Photo Taken: May 12, 1936 VIEW FROM SOUTHWEST - General Fremont House, 539 Hartnell Street, Monterey, Monterey County, CA

  8. 1. Historic American Buildings Survey Robert W. Kerrigan. Photographer Year ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Robert W. Kerrigan. Photographer Year Built: 1835 Photo Taken: May 12, 1936 SOUTHEAST - 160 (degrees) (VIEW FROM SOUTHWEST) - Stokes House, 500 Hartnell Street, Monterey, Monterey County, CA

  9. 2. Historic American Buildings Survey John O. Brostrup, Photographer October ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey John O. Brostrup, Photographer October 20, 1936 12:55 P. M. VIEW OF BARN FROM SOUTHWEST - Samuel Gaither Barn, 3101 Mount Carmel Cemetery Road, Unity, Montgomery County, MD

  10. 1. Historic American Buildings Survey John O. Brostrup, Photographer October ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey John O. Brostrup, Photographer October 20, 1936 12:50 P. M. VIEW FROM SOUTHWEST (front) - Samuel Gaither House, 3101 Mount Carmel Cemetery Road, Unity, Montgomery County, MD

  11. 13. Historic American Buildings Survey Cervin Robinson, Photographer June 1959 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Historic American Buildings Survey Cervin Robinson, Photographer June 1959 FIREPLACE (NORTHEAST) WALL IN SECOND FLOOR NORTH ROOM, VIEW FROM SOUTHWEST - Clough-Langdon House, 21 Unity Street, Boston, Suffolk County, MA

  12. 3. Historic American Buildings Survey Photocopy of 1964 photo, copyright ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Photocopy of 1964 photo, copyright Guy Gannett Publishing Co. VIEW FROM SOUTHWEST - U. S. Post Office & Old Courthouse, 169 Middle Street, Portland, Cumberland County, ME

  13. 2. Historic American Buildings Survey Philip Turner, Photographer Summer 1967 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Philip Turner, Photographer Summer 1967 SOUTH (FRONT) FACADE OF HOUSE AND CARRIAGE HOUSE FROM SOUTHWEST - Albert F. Madlener House, 4 West Burton Place, Chicago, Cook County, IL

  14. 1. Historic American Buildings Survey, Frederick Tilberg, Photographer August 25, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, Frederick Tilberg, Photographer August 25, 1957 EXTERIOR OF OVEN FROM THE SOUTHWEST. - Bricker Outdoor Bake Oven, Taneytown & Wheat Fields Roads, Gettysburg, Adams County, PA

  15. 18. Historic American Buildings Survey Photocopy of old view, date ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Historic American Buildings Survey Photocopy of old view, date unknown From collection of Anna B. Scherer, Lees Summit, Mo. SOUTHEAST AND SOUTHWEST FACADES - Longview Farm, Grandstand & Clubhouse, Longview Road, Lees Summit, Jackson County, MO

  16. 2. Historic American Buildings Survey Photo from Vischer Drawing California ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Photo from Vischer Drawing California Historical Society Original: August 16, 1866 (Vischer drawing) Re-photo: January 1940 VIEW FROM SOUTHWEST - Mission San Jose de Guadalupe, Mission & Washington Boulevards, Fremont, Alameda County, CA

  17. 1. Historic American Buildings Survey Courtesy of Historical Society of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Courtesy of Historical Society of Montana, Rephoto: 1963 VIRGINIA CITY - MONTANA TERRITORY 1866 - Content Corner, Southwest corner of Wallace & Jackson Streets, Virginia City, Madison County, MT

  18. 24. Historic American Buildings Survey, Frederick D. Nichols, Photographer June, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. Historic American Buildings Survey, Frederick D. Nichols, Photographer June, 1939 GREAT ROOM, VIEW LOOKING SOUTHWEST. - Second Bank of the United States, 420 Chestnut Street, Philadelphia, Philadelphia County, PA

  19. 1. Historic American Buildings Survey Copied by Survey, Photographer, Old ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey Copied by Survey, Photographer, Old Photo before 1880 (a) Ext-General view from Southwest. - Governor Thomas Prence House, King's Highway (U.S. Route 6), Eastham, Barnstable County, MA

  20. 3. Historic American Buildings Survey Harold Allen, Photographer 3 May ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Harold Allen, Photographer 3 May 1965 ENTRANCE CANOPY FROM SOUTHWEST - Holy Trinity Russian & Greek Orthodox Church, 1121 North Leavitt Street, Chicago, Cook County, IL

  1. 7. Historic American Buildings Survey George Eisenman, Photographer Summer 1967 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Historic American Buildings Survey George Eisenman, Photographer Summer 1967 BASEMENT, FIREPLACE SUPPORT IN SOUTHWEST CORNER - Adams-Mason House, 1072 Thomas Jefferson Street Northwest, Washington, District of Columbia, DC

  2. 2. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Alexander Piaget, Photographer, April 10, 1934 VIEW FROM SOUTHWEST - Jean Baptiste Valle House, 99 South Main Street (Northwest corner of Main & Market Streets), Sainte Genevieve, Ste. Genevieve County, MO

  3. 11. Historic American Buildings Survey P. A. Beaudoin, Photographer August ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Historic American Buildings Survey P. A. Beaudoin, Photographer August 1960 DETAILS OF THE SOUTHWEST CORNER AT THE SECOND FLOOR - Don Raimundo Arrivas House, 44 South George Street, Saint Augustine, St. Johns County, FL

  4. 4. Historic American Buildings Survey Thomas T. Waterman, Photographer 1938 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey Thomas T. Waterman, Photographer 1938 GATE PIER Now at Southwest Corner Fifteenth and Constitution Avenue - U.S. Capitol, Gateposts, Nineteenth Street & Constitution (moved from Capitol), Washington, District of Columbia, DC

  5. 3. Historic American Buildings Survey Albert S. Burns, Photographer c. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Albert S. Burns, Photographer c. 1934-35 VIEW FROM SOUTHWEST - U.S. Capitol, Intersection of North, South, & East Capitol Streets & Capitol Mall, Washington, District of Columbia, DC

  6. 15. Historic American Buildings Survey, July 15, 1936 (old photo, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Historic American Buildings Survey, July 15, 1936 (old photo, no date) LIBRARY, FIRST FLOOR, SOUTHWEST CORNER. DETAIL OF FIREPLACE AND BOOK CASES. - Judge A. V. Parson Mansion, 5 East Fourth Street, Williamsport, Lycoming County, PA

  7. 3. Historic American Buildings Survey Richard Koch, Photographer, April, 1934 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Richard Koch, Photographer, April, 1934 SOUTHWEST ELEVATION - Angelina Plantation (Dove Cote & Doll House), State Highway 1, Mount Airy, St. John the Baptist Parish, LA

  8. 2. Historic American Buildings Survey Richard Koch, Photographer, April, 1934 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Richard Koch, Photographer, April, 1934 SOUTHWEST ELEVATION - Angelina Plantation (Dove Cote & Doll House), State Highway 1, Mount Airy, St. John the Baptist Parish, LA

  9. 7. Historic American Buildings Survey, John A. Bryan, Photographer July ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Historic American Buildings Survey, John A. Bryan, Photographer July 9, 1952 CHAPEL AND CLASSROOM, SOUTHWEST PERSPECTIVE. - St. John's Episcopal Mission, Chapel & Rectory, Fort Bennett Vicinity, Green Grass, Dewey County, SD

  10. 4. Historic American Buildings Survey John O. Brostrup, Photographer March ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey John O. Brostrup, Photographer March 30, 1936 12:50 P. M. VIEW FROM SOUTHWEST - Friendship, Kolbies Corner, State Routes 214 & 556, Largo, Prince George's County, MD

  11. 8. Historic American Buildings Survey, Arthur W. Stewart, Photographer June ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Historic American Buildings Survey, Arthur W. Stewart, Photographer June 26, 1936 GENERAL VIEW AFTER 1919 STORM (SOUTHWEST ELEVATION). - Conrad Meuly House & Store, 210 Chaparral Street, Corpus Christi, Nueces County, TX

  12. 4. Historic American Buildings Survey, Glenn C. Wilson, Photographer March ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey, Glenn C. Wilson, Photographer March 1, 1934 VIEW OF SOUTHWEST CORNER, SHOWING RECENT ADDITION. - Friederich Homann Saddlery & Residence, 136 Seguin Street, New Braunfels, Comal County, TX

  13. 4. Historic American Buildings Survey, Paul L. and Sally L. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey, Paul L. and Sally L. Gordon, Photographers October 15, 1966, DETAIL OF DOOR, SOUTHWEST PARLOR, FIRST FLOOR. - Lindley M. Moore House, 22 Lake View Park, Rochester, Monroe County, NY

  14. 3. Historic American Buildings Survey, W. Eugene George, Jr., Photographer ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey, W. Eugene George, Jr., Photographer July, 1961 NORTHWEST ELEVATION (RIO GRANDE RIVER FACADE). - Leocadia Leandro Garcia House, Southwest corner of Main Plaza, Roma Creek, Starr County, TX

  15. 1. Historic American Buildings Survey, W. Eugene George, Jr., Photographer ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, W. Eugene George, Jr., Photographer July, 1961 SOUTHWEST ELEVATION, MAIN STREET. - Silverio De La Pena Drugstore & Post Office, Main & Lopez Streets, Rio Grande City, Starr County, TX

  16. 2. Historic American Buildings Survey, W. Eugene George, Jr., Photographer ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey, W. Eugene George, Jr., Photographer July, 1961 WEST ELEVATION (RIO GRANDE RIVER FACADE). - Leocadia Leandro Garcia House, Southwest corner of Main Plaza, Roma Creek, Starr County, TX

  17. 1. Historic American Buildings Survey, W. Eugene George, Jr., Photographer ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, W. Eugene George, Jr., Photographer July, 1961 NORTH ELEVATION (PLAZA FACADE). - Leocadia Leandro Garcia House, Southwest corner of Main Plaza, Roma Creek, Starr County, TX

  18. 4. Historic American Buildings Survey, W. Eugene George, Jr., Photographer ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey, W. Eugene George, Jr., Photographer July, 1961 SOUTH ELEVATION, REAR. - Leocadia Leandro Garcia House, Southwest corner of Main Plaza, Roma Creek, Starr County, TX

  19. 5. Historic American Buildings Survey, W. Eugene George, Jr., Photographer ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Historic American Buildings Survey, W. Eugene George, Jr., Photographer July, 1961 DETAIL OF ENTRANCE DOOR AND BALCONY (PLAZA FACADE). - Leocadia Leandro Garcia House, Southwest corner of Main Plaza, Roma Creek, Starr County, TX

  20. 3. Historic American Buildings Survey Courtesy of Title Insurance and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey Courtesy of Title Insurance and Trust Company Photo ca. 1888 SOUTHWEST ELEVATION - Cathedral of St. Vibiana, Second & Main Streets, Los Angeles, Los Angeles County, CA

  1. 2. Historic American Buildings Survey Courtesy of Title Insurance and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Courtesy of Title Insurance and Trust Company Photo ca. 1885 SOUTHWEST ELEVATION - Cathedral of St. Vibiana, Second & Main Streets, Los Angeles, Los Angeles County, CA

  2. 6. Historic American Buildings Survey John O. Brostrup, Photographer September ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey John O. Brostrup, Photographer September 4, 1936 10:50 A. M. VIEW OF SLAVE QUARTERS FROM SOUTHWEST (front.) - Rock Hall & Slave Quarters, Dickerson, Montgomery County, MD

  3. 29. Historic American Buildings Survey Albert S. Burns, Photographer September ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. Historic American Buildings Survey Albert S. Burns, Photographer September 30, 1935. MANTEL, SOUTHWEST BEDROOM - 2d FLOOR - The Maples, 630 South Carolina Avenue Southeast, Washington, District of Columbia, DC

  4. 23. Historic American Buildings Survey John O. Brostrup, Photographer Nov. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Historic American Buildings Survey John O. Brostrup, Photographer Nov. 17, 1936 9:30 A.M. SOUTHWEST CORNER OF SOUTHEAST ROOM (DRAWING ROOM) - The Maples, 630 South Carolina Avenue Southeast, Washington, District of Columbia, DC

  5. 1. Historic American Buildings Survey From Society of California Pioneers ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey From Society of California Pioneers Painting by Renaud Original: Before 1835 Re-photo: January 1940 VIEW FROM SOUTHWEST - Mission San Rafael Archangel, San Rafael, Marin County, CA

  6. Snow in Southwest United States

    NASA Technical Reports Server (NTRS)

    2002-01-01

    In late December, the Southwest was blanketed with snow, and this scence was captured by MODIS on December 27, 2001. The white drape contrasts sharply with the red rock of the Colorado Plateau, a geologic region made up of a succession of plateaus and mesas composed mostly of sedimentary rock, whose reddish hues indicate the presence of oxidized iron. The Plateau covers the Four Corners area of the Southwest, including (clockwise from upper left) southern Utah, Colorado, New Mexico, and Arizona. The region gets its name from the Colorado River, seen most prominently as a dark ribbon running southwest through southern Utah. At the upper left of the image, a bank of low clouds partially obscures Utah's Great Salt Lake, but its faint outline is still visible. To the east and southeast of the lake, some high peaks of the Wasatch Mountain range break free of the clouds. The Park City area, one of the 2002 Winter Olympic venues, can be seen poking through the cloud deck about 75km southeast of the lake. Farther east, the dark Uinta Mountains follow the border between Colorado and Wyoming. The Uinta are one of the rare east-west running ranges of the Rocky Mountains.

  7. Distribution of desert varnish in Arizona

    NASA Technical Reports Server (NTRS)

    Elvidge, Christopher D.

    1989-01-01

    Desert varnish is the dark coat of clay and ferromanganese oxides developed on exposed rock surfaces in arid regions. It forms from the accretion of material from windblown dust. The distribution of desert varnish was mapped in Arizona. It was discovered that desert varnish could be mapped on a regional scale. Well developed desert varnish is common on stable rock surfaces in areas having alkaline soils and less than about 25 cm of annual precipitation. Rock surfaces in areas having more than 40 cm of annual precipitation are generally devoid of desert varnish. An experiment was conducted with varnished desert pavement stone. The stones were broken in half and half was set on a roof in central Illinois from April until October. Removed from the alkaline desert environment, it only took seven months for the varnish to develop an eroded appearance. This experiment graphically illustrates the dependency of desert varnish on alkalinity. In this context, the zones of eroded desert varnish in Arizona indicate that the area of active desert varnish formation has fluctuated, expanding in drier times and contracting/eroding in wetter times.

  8. Controls on the variability of net infiltration to desert sandstone

    USGS Publications Warehouse

    Heilweil, V.M.; McKinney, T.S.; Zhdanov, M.S.; Watt, D.E.

    2007-01-01

    As populations grow in and climates and desert bedrock aquifers are increasingly targeted for future development, understanding and quantifying the spatial variability of net infiltration becomes critically important for accurately inventorying water resources and mapping contamination vulnerability. This paper presents a conceptual model of net infiltration to desert sandstone and then develops an empirical equation for its spatial quantification at the watershed scale using linear least squares inversion methods for evaluating controlling parameters (independent variables) based on estimated net infiltration rates (dependent variables). Net infiltration rates used for this regression analysis were calculated from environmental tracers in boreholes and more than 3000 linear meters of vadose zone excavations in an upland basin in southwestern Utah underlain by Navajo sandstone. Soil coarseness, distance to upgradient outcrop, and topographic slope were shown to be the primary physical parameters controlling the spatial variability of net infiltration. Although the method should be transferable to other desert sandstone settings for determining the relative spatial distribution of net infiltration, further study is needed to evaluate the effects of other potential parameters such as slope aspect, outcrop parameters, and climate on absolute net infiltration rates. Copyright 2007 by the American Geophysical Union.

  9. Assessing shrub encroachment in a grassland-shrubland desert ecotone using the relationship between remote sensed phenology of vegetation and precipitation

    NASA Astrophysics Data System (ADS)

    Moreno de las Heras, Mariano; Diaz-Sierra, Ruben; Wainwright, John

    2014-05-01

    monsoonal summer rainfall. For shrubs, NPP is better explained by winter plus summer precipitation, overlapping the monsoonal period of rain concentration. Our results suggest that a precipitation drift driven by reductions in monsoonal summer rainfall and increases in winter precipitation may enhance the shrub-encroachment process in the desert grasslands studied in the American Southwest.

  10. Arid lands of the Southwest

    USGS Publications Warehouse

    Thorsteinson, Lyman

    2005-01-01

    When thinking about plants and animals that inhabit hot arid lands of the southwestern U.S., fish are easily overlooked by most people. However, these desert lands often contain isolated springs or cienegas (a Spanish term referring to permanently saturated 'seep wetlands') and streams supporting native fishes that occur no where else in the world. These aquatic remnants from the last Ice Age have survived for thousands of years due to an amazing ability to tolerate harsh environmental conditions, especially extremely high water temperatures, high salinities, and unpredictable water flows.

  11. An Ecological Study of Food Desert Prevalence and 4th Grade Academic Achievement in New York State School Districts

    PubMed Central

    Frndak, Seth E.

    2014-01-01

    Background This ecological study examines the relationship between food desert prevalence and academic achievement at the school district level. Design and methods Sample included 232 suburban and urban school districts in New York State. Multiple open-source databases were merged to obtain: 4th grade science, English and math scores, school district demographic composition (NYS Report Card), regional socioeconomic indicators (American Community Survey), school district quality (US Common Core of Data), and food desert data (USDA Food Desert Atlas). Multiple regression models assessed the percentage of variation in achievement scores explained by food desert variables, after controlling for additional predictors. Results The proportion of individuals living in food deserts significantly explained 4th grade achievement scores, after accounting for additional predictors. School districts with higher proportions of individuals living in food desert regions demonstrated lower 4th grade achievement across science, English and math. Conclusions Food deserts appear to be related to academic achievement at the school district level among urban and suburban regions. Further research is needed to better understand how food access is associated with academic achievement at the individual level. Significance for public health The prevalence of food deserts in the United States is of national concern. As poor nutrition in United States children continues to spark debate, food deserts are being evaluated as potential sources of low fruit and vegetable intake and high obesity rates. Cognitive development and IQ have been linked to nutrition patterns, suggesting that children in food desert regions may have a disadvantage academically. This research evaluates if an ecological relationship between food desert prevalence and academic achievement at the school district level can be demonstrated. Results suggest that food desert prevalence may relate to poor academic performance at

  12. Egypt western desert activity hits high gear

    SciTech Connect

    Petzet, G.A.

    1996-11-04

    Exploration in Egypt`s western desert is turning up large oil and gas reserves in several sub-basins. Though not a threat to the Gulf of Suez`s oil production dominance, the western desert`s output is climbing. And gas production is also set to rise as more pipelines are built. The paper describes the geology, Qarun field production, further exploration at Qarun and the Khalda/Obaiyed gas.

  13. Network topology of the desert rose

    NASA Astrophysics Data System (ADS)

    Hope, Sigmund; Kundu, Sumanta; Roy, Chandreyee; Manna, Subhrangshu; Hansen, Alex

    2015-09-01

    Desert roses are gypsum crystals that consist of intersecting disks. We determine their geometrical structure using computer assisted tomography. By mapping the geometrical structure onto a graph, the topology of the desert rose is analyzed and compared to a model based on diffusion limited aggregation. By comparing the topology, we find that the model gets a number of the features of the real desert rose right, whereas others do not fit so well.

  14. The age of the Taklimakan Desert.

    PubMed

    Sun, Jimin; Liu, Tungsheng

    2006-06-16

    The Taklimakan Desert is located in the foreland basin of the Tibetan Plateau. We report here the results of stratigraphic investigations of a 1626-meter-thick sequence with interbedded wind-blown silt from the southern marginal Taklimakan Desert. Because the studied section is located downwind of the desert, the eolian silt accumulation is closely linked to desert formation. Our new evidence indicates that shifting sand dunes prevailed in the Tarim Basin by at least 5.3 million years ago, as they do today. We attribute this event to late Cenozoic climatic deterioration, as well as to changes in atmospheric circulation induced by Tibetan Plateau uplift.

  15. EFFECTS OF ELEVATED CO2 ON ROOT FUNCTION AND SOIL RESPIRATION IN A MOJAVE DESERT ECOSYSTEM

    SciTech Connect

    Nowak, Robert S.

    2007-12-19

    Increases in atmospheric CO{sub 2} concentration during the last 250 years are unequivocal, and CO{sub 2} will continue to increase at least for the next several decades (Houghton et al. 2001, Keeling & Whorf 2002). Arid ecosystems are some of the most important biomes globally on a land surface area basis, are increasing in area at an alarming pace (Dregne 1991), and have a strong coupling with regional climate (Asner & Heidebrecht 2005). These water-limited ecosystems also are predicted to be the most sensitive to elevated CO{sub 2}, in part because they are stressful environments where plant responses to elevated CO{sub 2} may be amplified (Strain & Bazzaz 1983). Indeed, all C{sub 3} species examined at the Nevada Desert FACE Facility (NDFF) have shown increased A{sub net} under elevated CO{sub 2} (Ellsworth et al. 2004, Naumburg et al. 2003, Nowak et al. 2004). Furthermore, increased shoot growth for individual species under elevated CO{sub 2} was spectacular in a very wet year (Smith et al. 2000), although the response in low to average precipitation years has been smaller (Housman et al. 2006). Increases in perennial cover and biomass at the NDFF are consistent with long term trends in the Mojave Desert and elsewhere in the Southwest, indicating C sequestration in woody biomass (Potter et al. 2006). Elevated CO{sub 2} also increases belowground net primary production (BNPP), with average increases of 70%, 21%, and 11% for forests, bogs, and grasslands, respectively (Nowak et al. 2004). Although detailed studies of elevated CO{sub 2} responses for desert root systems were virtually non-existent prior to our research, we anticipated that C sequestration may occur by desert root systems for several reasons. First, desert ecosystems exhibit increases in net photosynthesis and primary production at elevated CO{sub 2}. If large quantities of root litter enter the ecosystem at a time when most decomposers are inactive, significant quantities of carbon may be stored

  16. Ritual drinks in the pre-Hispanic US Southwest and Mexican Northwest

    PubMed Central

    Crown, Patricia L.; Gu, Jiyan; Hurst, W. Jeffrey; Ward, Timothy J.; Bravenec, Ardith D.; Ali, Syed; Kebert, Laura; Berch, Marlaina; Redman, Erin; Lyons, Patrick D.; Merewether, Jamie; Phillips, David A.; Reed, Lori S.; Woodson, Kyle

    2015-01-01

    Chemical analyses of organic residues in fragments of pottery from 18 sites in the US Southwest and Mexican Northwest reveal combinations of methylxanthines (caffeine, theobromine, and theophylline) indicative of stimulant drinks, probably concocted using either cacao or holly leaves and twigs. The results cover a time period from around A.D. 750–1400, and a spatial distribution from southern Colorado to northern Chihuahua. As with populations located throughout much of North and South America, groups in the US Southwest and Mexican Northwest likely consumed stimulant drinks in communal, ritual gatherings. The results have implications for economic and social relations among North American populations. PMID:26372965

  17. Ritual drinks in the pre-Hispanic US Southwest and Mexican Northwest.

    PubMed

    Crown, Patricia L; Gu, Jiyan; Hurst, W Jeffrey; Ward, Timothy J; Bravenec, Ardith D; Ali, Syed; Kebert, Laura; Berch, Marlaina; Redman, Erin; Lyons, Patrick D; Merewether, Jamie; Phillips, David A; Reed, Lori S; Woodson, Kyle

    2015-09-15

    Chemical analyses of organic residues in fragments of pottery from 18 sites in the US Southwest and Mexican Northwest reveal combinations of methylxanthines (caffeine, theobromine, and theophylline) indicative of stimulant drinks, probably concocted using either cacao or holly leaves and twigs. The results cover a time period from around A.D. 750-1400, and a spatial distribution from southern Colorado to northern Chihuahua. As with populations located throughout much of North and South America, groups in the US Southwest and Mexican Northwest likely consumed stimulant drinks in communal, ritual gatherings. The results have implications for economic and social relations among North American populations.

  18. Ritual drinks in the pre-Hispanic US Southwest and Mexican Northwest.

    PubMed

    Crown, Patricia L; Gu, Jiyan; Hurst, W Jeffrey; Ward, Timothy J; Bravenec, Ardith D; Ali, Syed; Kebert, Laura; Berch, Marlaina; Redman, Erin; Lyons, Patrick D; Merewether, Jamie; Phillips, David A; Reed, Lori S; Woodson, Kyle

    2015-09-15

    Chemical analyses of organic residues in fragments of pottery from 18 sites in the US Southwest and Mexican Northwest reveal combinations of methylxanthines (caffeine, theobromine, and theophylline) indicative of stimulant drinks, probably concocted using either cacao or holly leaves and twigs. The results cover a time period from around A.D. 750-1400, and a spatial distribution from southern Colorado to northern Chihuahua. As with populations located throughout much of North and South America, groups in the US Southwest and Mexican Northwest likely consumed stimulant drinks in communal, ritual gatherings. The results have implications for economic and social relations among North American populations. PMID:26372965

  19. Genetic diversity of the endangered endemic Agave victoriae-reginae (Agavaceae) in the Chihuahuan Desert.

    PubMed

    Martínez-Palacios, A; Eguiarte, L E; Furnier, G R

    1999-08-01

    Long-lived perennials are a species-rich, ecologically important component of the North American deserts, yet we know little about their genetic structure, information important for their conservation. Agave victoriae-reginae is an endemic of the Chihuahuan Desert of northern Mexico that is endangered by collection for the ornamental trade. We examined levels and patterns of variation at ten polymorphic allozyme loci in ten populations representing the range of the species. Levels of genetic variation (mean H(e)= 0.335) and differentiation (mean F(ST) = 0.236) were high. Phenetic clustering suggested the existence of at least three distinct groups of populations. If this pattern of variation is representative of other long-lived desert perennials, it may explain the species richness of this group and will pose a real challenge to gene conservation efforts.

  20. Desert winds; monitoring wind-related surface processes in Arizona, New Mexico, and California

    USGS Publications Warehouse

    Breed, Carol S.; Reheis, Marith C.

    1999-01-01

    The 18-year Desert Winds Project established instrumented field sites in the five major regions of the North American Desert to obtain meteorological, geological, and vegetation data for natural desert sites affected by wind erosion. The eight chapters in this volume describe the settings and operation of the stations and summarize eolian-related research to date around the stations. The report includes studies of the sand-moving effectiveness of storm winds, wind-erosion susceptibility of different ground-surface types, relations of dust storms to meteorological conditions, mediation of wind erosion by vegetation, remote sensing to detect vegetation changes related to climate change, and comparison of regional dust deposition to that near Owens (dry) Lake.

  1. Dynamic Response of Southwest Juniper to Shifting Climate and Natural and Anthropogenic Changes in Atmospheric pCO2

    NASA Astrophysics Data System (ADS)

    Zinniker, D. A.; Holmgren, C. A.; Pagani, M.

    2008-12-01

    % increase in carbon assimilation rates in response to anthropogenic CO2. This average increase is associated with greater assimilation rate variability as juniper continues to colonize more diverse and generally drier sites. Variable but generally heavier deuterium isotope values indicate increasing growth during periods of aridity and a general lengthening of juniper growing seasons. Expansion of juniper woodlands under the influence of anthropogenic CO2 is likely to continue where water loss limits growth. Carbon assimilation rates during periods of water stress will also increase. In mesic sites other environmental factors may become limiting (e.g. nutrients, light, or competition), reducing the continuing impact of CO2 fertilization. Widespread establishment of new juniper woodlands could significantly affect the hydrology in the southwest US due to direct canopy interception of precipitation, increased runoff, increased transpirational use of deep groundwater, and amplification of the North American Monsoon through transpirational evaporation. New desert woodlands form a net carbon sink for anthropogenic CO2, but the size, stability, and continued growth of this reservoir depend on complex interactions between plants and our changing environment.

  2. Resistance to invasion and resilience to fire in desert shrublands of North America

    USGS Publications Warehouse

    Brooks, Matthew L.; Chambers, Jeanne C.

    2011-01-01

    Settlement by Anglo-Americans in the desert shrublands of North America resulted in the introduction and subsequent invasion of multiple nonnative grass species. These invasions have altered presettlement fire regimes, resulted in conversion of native perennial shrublands to nonnative annual grasslands, and placed many native desert species at risk. Effective management of these ecosystems requires an understanding of their ecological resistance to invasion and resilience to fire. Resistance and resilience differ among the cold and hot desert shrublands of the Great Basin, Mojave, Sonoran, and Chihuahuan deserts in North America. These differences are largely determined by spatial and temporal patterns of productivity but also are affected by ecological memory, severity and frequency of disturbance, and feedbacks among invasive species and disturbance regimes. Strategies for preventing or managing invasive plant/fire regimes cycles in desert shrublands include: 1) conducting periodic resource assessments to evaluate the probability of establishment of an altered fire regime; 2) developing an understanding of ecological thresholds associate within invasion resistance and fire resilience that characterize transitions from desirable to undesirable fire regimes; and 3) prioritizing management activities based on resistance of areas to invasion and resilience to fire.

  3. Tradeoffs and synergies between biofuel production and large-scale solar infrastructure in deserts

    NASA Astrophysics Data System (ADS)

    Ravi, S.; Lobell, D. B.; Field, C. B.

    2012-12-01

    Solar energy installations in deserts are on the rise, fueled by technological advances and policy changes. Deserts, with a combination of high solar radiation and availability of large areas unusable for crop production are ideal locations for large scale solar installations. For efficient power generation, solar infrastructures require large amounts of water for operation (mostly for cleaning panels and dust suppression), leading to significant moisture additions to desert soil. A pertinent question is how to use the moisture inputs for sustainable agriculture/biofuel production. We investigated the water requirements for large solar infrastructures in North American deserts and explored the possibilities for integrating biofuel production with solar infrastructure. In co-located systems the possible decline in yields due to shading by solar panels may be offsetted by the benefits of periodic water addition to biofuel crops, simpler dust management and more efficient power generation in solar installations, and decreased impacts on natural habitats and scarce resources in deserts. In particular, we evaluated the potential to integrate solar infrastructure with biomass feedstocks that grow in arid and semi-arid lands (Agave Spp), which are found to produce high yields with minimal water inputs. To this end, we conducted detailed life cycle analysis for these coupled agave biofuel - solar energy systems to explore the tradeoffs and synergies, in the context of energy input-output, water use and carbon emissions.

  4. Magnetic Analysis Techniques Applied to Desert Varnish

    NASA Technical Reports Server (NTRS)

    Schmidgall, E. R.; Moskowitz, B. M.; Dahlberg, E. D.; Kuhlman, K. R.

    2003-01-01

    Desert varnish is a black or reddish coating commonly found on rock samples from arid regions. Typically, the coating is very thin, less than half a millimeter thick. Previous research has shown that the primary components of desert varnish are silicon oxide clay minerals (60%), manganese and iron oxides (20-30%), and trace amounts of other compounds [1]. Desert varnish is thought to originate when windborne particles containing iron and manganese oxides are deposited onto rock surfaces where manganese oxidizing bacteria concentrate the manganese and form the varnish [4,5]. If desert varnish is indeed biogenic, then the presence of desert varnish on rock surfaces could serve as a biomarker, indicating the presence of microorganisms. This idea has considerable appeal, especially for Martian exploration [6]. Magnetic analysis techniques have not been extensively applied to desert varnish. The only previous magnetic study reported that based on room temperature demagnetization experiments, there were noticeable differences in magnetic properties between a sample of desert varnish and the substrate sandstone [7]. Based upon the results of the demagnetization experiments, the authors concluded that the primary magnetic component of desert varnish was either magnetite (Fe3O4) or maghemite ( Fe2O3).

  5. Off-Road and the Fragile Desert

    ERIC Educational Resources Information Center

    Stebbins, Robert C.

    1974-01-01

    Part one of a two-part article sets forth the dimensions and the political-cultural aspects of the use of off-road vehicles in desert areas. Presents arguments for and against off-road vehicle use on national-resource land as exemplified in the California Desert. (Editor/JR)

  6. Mesozoic rift basins in western desert of Egypt, their southern extension and impact on future exploration

    SciTech Connect

    Taha, M.A. )

    1988-08-01

    Rift basins are a primary target of exploration in east, central, and west Africa. These intracratonic rift basins range in age from the Triassic to the Neogene and are filled with lagoonal-lacustrine sand-shale sequences. Several rift basins may be present in the Western Desert of Egypt. In the northeastern African platform, the Mesozoic Tethyan strand lines were previously interpreted to have limited southern extension onto the continent. This concept, based upon a relatively limited amount of subsurface data, has directed and focused the exploration for oil and gas to the northernmost 120 km of the Western Desert of Egypt. Recent well and geophysical data indicate a southerly extension of mesozoic rift basins several hundred kilometers inland from the Mediterranean Sea. Shushan/Faghur and Abu Gharadig/Bahrein basins may represent subparallel Mesozoic basins, trending northeast-southwest. Marine Oxfordian-Kimmeridgian sediments were recently reported from wells drilled approximately 500 km south of the present-day Mediterranean shoreline. The link of these basins with the Sirte basin to the southwest in Libya is not well understood. Exploration is needed to evaluate the hydrocarbon potential of such basins.

  7. Desert landforms of southwest Egypt: A basis for comparison with Mars

    NASA Technical Reports Server (NTRS)

    El-Baz, F. (Editor); Maxwell, T. A. (Editor)

    1982-01-01

    Geologic interpretations of The Gilf Kebir-Uweinat of Apollo-Soyuz photographs were verified. The photographs and LANDSAT images showed features reminiscent of those depicted by Mariner and Viking missions to Mars. These features were to better understand their morphologic analogs on Mars. It is indicated that climate change played a significant role in the formation of the eastern Sahara. It is also revealed that correlations between the eolian features in southwestern Egypt and the wind blown patterns on the surface of Mars result in a better understanding of eolian activity on both planets.

  8. 76 FR 8730 - Desert Southwest Customer Service Region-Rate Order No. WAPA-151

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ... CFR part 903) were published on September 18, 1985 (50 FR 37835). After review of public comments, and... would go into effect on October 1, 2011, and would remain in effect through September 30, 2016, or until superseded.\\1\\ The new rate schedule for GI Service, under Rate Schedule DSW-GI1, would go into effect...

  9. Stratospheric contribution to surface ozone in the desert Southwest during the 2013 Las Vegas Ozone Study

    NASA Astrophysics Data System (ADS)

    Langford, A. O.; Senff, C. J.; Alvarez, R. J. _II, II; Brioude, J. F.; Cooper, O. R.; Holloway, J. S.; Lin, M.; Marchbanks, R.; Pierce, R. B.; Reddy, P. J.; Sandberg, S.; Weickmann, A. M.; Williams, E. J.; Gustin, M. S.; Iraci, L. T.; Leblanc, T.; Yates, E. L.

    2014-12-01

    The 2013 Las Vegas Ozone Study (LVOS) was designed to investigate the potential impact of stratosphere-troposphere transport (STT) and long-range transport of pollution from Asia on surface O3 concentrations in Clark County, NV. This measurement campaign, which took place in May and June of 2013, was conducted at Angel Peak, NV, a high elevation site about 2.8 km above mean sea level and 45 km west of Las Vegas. The study was organized around the NOAA ESRL truck-based TOPAZ scanning ozone lidar with collocated in situ sampling of O3, CO, and meteorological parameters. These measurements were supported by the NOAA/NESDIS real time modelling system (RAQMS), FLEXPART particle dispersion model, and the NOAA GFDL AM3 model. In this talk, I will describe one of several STT events that occurred during the LVOS campaign. This intrusion, which was profiled by TOPAZ on the night of May 24-25, was also sampled by the NASA Alpha Jet, the Table Mountain ozone lidar, and by an ozonesonde flying above southern California. This event also led to significant ozone increases at surface monitors operated by Clark County, the California Air Resources Board, the U.S. National Park Service, and the Nevada Rural Ozone Initiative (NRVOI), and resulted in exceedances of the 2008 75 ppbv O3 NAAQS both in Clark County and in surrounding areas of Nevada and southern California. The potential implications of this and similar events for air quality compliance in the western U.S. will be discussed.

  10. Wildlife conservation and solar energy development in the Desert Southwest, United States

    USGS Publications Warehouse

    Lovich, Jeffrey E.; Ennen, Josua R.

    2011-01-01

    Large areas of public land are currently being permitted or evaluated for utility-scale solar energy development (USSED) in the southwestern United States, including areas with high biodiversity and protected species. However, peer-reviewed studies of the effects of USSED on wildlife are lacking. The potential effects of the construction and the eventual decommissioning of solar energy facilities include the direct mortality of wildlife; environmental impacts of fugitive dust and dust suppressants; destruction and modification of habitat, including the impacts of roads; and off-site impacts related to construction material acquisition, processing, and transportation. The potential effects of the operation and maintenance of the facilities include habitat fragmentation and barriers to gene flow, increased noise, electromagnetic field generation, microclimate alteration, pollution, water consumption, and fire. Facility design effects, the efficacy of site-selection criteria, and the cumulative effects of USSED on regional wildlife populations are unknown. Currently available peer-reviewed data are insufficient to allow a rigorous assessment of the impact of USSED on wildlife.

  11. Bioaerosols from the land application of biosolids in the desert southwest USA.

    PubMed

    Brooks, J P; Tanner, B D; Josephson, K L; Gerba, C P; Pepper, I L

    2004-01-01

    This study evaluated bioaerosol emissions during land application of Class B biosolids in and around Tucson, Arizona, to aid in developing models of the fate and transport of bioaerosols generated from the land application of biosolids. Samples were collected for 20 min at distances between 2 m and 20 m downwind of point sources, using an SKC BioSampler impinger. A total of six samples were collected per sampling event, which consisted of a biosolid spray applicator applying liquid biosolids to a cotton field. Each application represented one exposure. Samples were collected in deionised water amended with peptone and antifoam agent. Ambient weather conditions were also monitored every 10 min following initiation of sampling. Concurrently with downwind samples, background (ambient) air samples were collected to compensate for any ambient airborne microorganisms. In addition, biosolids samples were collected for analysis of target indicator and pathogenic organisms. Soil samples were also collected and analysed. Significant numbers of heterotrophic plate count (HPC) bacteria were found in air samples collected during the biosolid application process. These could have arisen from soil particles being aerosolised during the land application process. Aerosolised soil may contribute significantly to the amount of aerosolised microorganisms. Soil particles may be able to more readily aerosolise, due to their low density, small particle size and low mass. Aerosolised HPC bacteria found during biosolids land application were similar to those found during normal tractor operation on non-biosolids applied fields. Coliforms and coliphages were not routinely detected even though they were found to be present in the biosolids at relatively high concentrations, 10(6) and 10(4)/g (dry weight) of biosolids respectively. This could be due to the die-off rate of aerosolised Gram-negative bacteria or sorption to the solid portion of the biosolids. Low numbers of aerosolised coliphages may likewise be due to sorption phenomena. We theorise that only organisms in the aqueous phase of the biosolids were available to desorb and be aerosolised. Animal viruses, which were not detected in the biosolids, were likewise not detected in the aerosol samples. Clostridium perfringens was detected in only a small percent of aerosol samples although it was detected during all weather conditions; other microorganisms were detected during more favourable environmental conditions (relative humidity >10%). Despite the fact that many of these organisms were present in the biosolids at significant concentrations, their presence in bioaerosols generated during the land application of biosolids was limited to only a small percentage of samples. Bacteria as well as viruses may sorb to biosolids, which contain a high percentage of organic matter, and desorption during land application of biosolids may not readily take place; therefore, these microorganisms may not be readily aerosolised. PMID:15318479

  12. Desert wildfire and severe drought diminish survivorship of the long-lived Joshua Tree (Yucca brevifolia; Agavaceae)

    USGS Publications Warehouse

    DeFalco, L.A.; Esque, T.C.; Scoles-Sciulla, S. J.; Rodgers, J.

    2010-01-01

    Extreme climate events are transforming plant communities in the desert Southwest of the United States. Abundant precipitation in 1998 associated with El Ni??o Southern Oscillation (ENSO) stimulated exceptional alien annual plant production in the Mojave Desert that fueled wildfires in 1999. Exacerbated by protracted drought, 80% of the burned Yucca brevifolia, a long-lived arborescent monocot, and 26% of unburned plants died at Joshua Tree National Park by 2004. Many burned plants < 1 m tall died immediately, and survival of all but the tallest, oldest plants declined to the same low level by 2004. Postfire sprouting prolonged survival, but only at the wetter, high-elevation sites. During succeeding dry years, herbaceous plants were scarce, and individuals of Thomomys bottae (pocket gopher) gnawed the periderm and hollowed stems of Y. brevifolia causing many of them to topple. Thomomys bottae damage reduced plant survivorship at low-elevation, unburned sites and diminished survival of burned plants in all but the driest site, which already had low survival. Accentuated ENSO episodes and more frequent wildfires are expected for the desert Southwest and will likely shift Y. brevifolia population structure toward tall, old adults with fewer opportunities for plant recruitment, thus imperiling the persistence of this unique plant community.

  13. Desert wildfire and severe drought diminish survivorship of the long-lived Joshua tree (Yucca brevifolia; Agavaceae).

    PubMed

    Defalco, Lesley A; Esque, Todd C; Scoles-Sciulla, Sara J; Rodgers, Jane

    2010-02-01

    Extreme climate events are transforming plant communities in the desert Southwest of the United States. Abundant precipitation in 1998 associated with El Niño Southern Oscillation (ENSO) stimulated exceptional alien annual plant production in the Mojave Desert that fueled wildfires in 1999. Exacerbated by protracted drought, 80% of the burned Yucca brevifolia, a long-lived arborescent monocot, and 26% of unburned plants died at Joshua Tree National Park by 2004. Many burned plants <1 m tall died immediately, and survival of all but the tallest, oldest plants declined to the same low level by 2004. Postfire sprouting prolonged survival, but only at the wetter, high-elevation sites. During succeeding dry years, herbaceous plants were scarce, and individuals of Thomomys bottae (pocket gopher) gnawed the periderm and hollowed stems of Y. brevifolia causing many of them to topple. Thomomys bottae damage reduced plant survivorship at low-elevation, unburned sites and diminished survival of burned plants in all but the driest site, which already had low survival. Accentuated ENSO episodes and more frequent wildfires are expected for the desert Southwest and will likely shift Y. brevifolia population structure toward tall, old adults with fewer opportunities for plant recruitment, thus imperiling the persistence of this unique plant community.

  14. The evolution of social behavior in the prehistoric American southwest.

    PubMed

    Gumerman, George J; Swedlund, Alan C; Dean, Jeffrey S; Epstein, Joshua M

    2003-01-01

    Long House Valley, located in the Black Mesa area of northeastern Arizona (USA), was inhabited by the Kayenta Anasazi from circa 1800 B.C. to circa A.D. 1300. These people were prehistoric precursors of the modern Pueblo cultures of the Colorado Plateau. A rich paleoenvironmental record, based on alluvial geomorphology, palynology, and dendroclimatology, permits the accurate quantitative reconstruction of annual fluctuations in potential agricultural production (kg maize/hectare). The archaeological record of Anasazi farming groups from A.D. 200 to 1300 provides information on a millennium of sociocultural stasis, variability, change, and adaptation. We report on a multi-agent computational model of this society that closely reproduces the main features of its actual history, including population ebb and flow, changing spatial settlement patterns, and eventual rapid decline. The agents in the model are monoagriculturalists, who decide both where to situate their fields and where to locate their settlements.

  15. Evidence of cacao use in the Prehispanic American Southwest.

    PubMed

    Crown, Patricia L; Hurst, W Jeffrey

    2009-02-17

    Chemical analyses of organic residues in fragments of ceramic vessels from Pueblo Bonito in Chaco Canyon, New Mexico, reveal theobromine, a biomarker for cacao. With an estimated 800 rooms, Pueblo Bonito is the largest archaeological site in Chaco Canyon and was the center of a large number of interconnected towns and villages spread over northwestern New Mexico. The cacao residues come from pieces of vessels that are likely cylinder jars, special containers occurring almost solely at Pueblo Bonito and deposited in caches at the site. This first known use of cacao drinks north of the Mexican border indicates exchange with cacao cultivators in Mesoamerica in a time frame of about A.D. 1000-1125. The association of cylinder jars and cacao beverages suggests that the Chacoan ritual involving the drinking of cacao was tied to Mesoamerican rituals incorporating cylindrical vases and cacao. The importance of Pueblo Bonito within the Chacoan world likely lies in part with the integration of Mesoamerican ritual, including critical culinary ingredients.

  16. Evidence of cacao use in the Prehispanic American Southwest

    PubMed Central

    Crown, Patricia L.; Hurst, W. Jeffrey

    2009-01-01

    Chemical analyses of organic residues in fragments of ceramic vessels from Pueblo Bonito in Chaco Canyon, New Mexico, reveal theobromine, a biomarker for cacao. With an estimated 800 rooms, Pueblo Bonito is the largest archaeological site in Chaco Canyon and was the center of a large number of interconnected towns and villages spread over northwestern New Mexico. The cacao residues come from pieces of vessels that are likely cylinder jars, special containers occurring almost solely at Pueblo Bonito and deposited in caches at the site. This first known use of cacao drinks north of the Mexican border indicates exchange with cacao cultivators in Mesoamerica in a time frame of about A.D. 1000–1125. The association of cylinder jars and cacao beverages suggests that the Chacoan ritual involving the drinking of cacao was tied to Mesoamerican rituals incorporating cylindrical vases and cacao. The importance of Pueblo Bonito within the Chacoan world likely lies in part with the integration of Mesoamerican ritual, including critical culinary ingredients. PMID:19188605

  17. Trees, chemistry, and prehistory in the American Southwest

    USGS Publications Warehouse

    Durand, S.R.; Shelley, P.H.; Antweiler, R.C.; Taylor, H.E.

    1999-01-01

    At least 200 000 trees were used in the building construction in Chaco Canyon, New Mexico, from about (AD) 850-1150. A large portion of these construction timbers were transported 50 km or more and the harvesting location(s) is not known. We argue that a feasible method for determining the wood source areas is to chemically characterize the possible source areas using modern wood and then attempt to match the prehistoric timbers to the modern signatures. This paper establishes the feasibility of this method. ICP-AES was employed to obtain element concentration values for 29 elements, from 62 trees, on three bedrock types. We conclude that it is possible to isolate the variation due to lithology if one controls for wood type (bark, sapwood, heartwood). In addition, ICP-MS was used for the analysis of a small sample of ancient wood. Data from these determinations are presented and the results indicate that the elemental variation is consistent with the most current model of wood use practices in Chaco Canyon. The methods pioneered here should be broadly applicable for determining wood source areas.

  18. Desert Test Site Uniformity Analysis

    NASA Technical Reports Server (NTRS)

    Kerola, Dana X.; Bruegge, Carol J.

    2009-01-01

    Desert test sites such as Railroad Valley (RRV) Nevada, Egypt-1, and Libya-4 are commonly targeted to assess the on-orbit radiometric performance of sensors. Railroad Valley is used for vicarious calibration experiments, where a field-team makes ground measurements to produce accurate estimates of top-of-atmosphere (TOA) radiances. The Sahara desert test sites are not instrumented, but provide a stable target that can be used for sensor cross-comparisons, or for stability monitoring of a single sensor. These sites are of interest to NASA's Atmospheric Carbon Observation from Space (ACOS) and JAXA's Greenhouse Gas Observation SATellite (GOSAT) programs. This study assesses the utility of these three test sites to the ACOS and GOSAT calibration teams. To simulate errors in sensor-measured radiance with pointing errors, simulated data have been created using MODIS Aqua data. MODIS data are further utilized to validate the campaign data acquired from June 22 through July 5, 2009. The first GOSAT vicarious calibration experiment was conducted during this timeframe.

  19. Catastrophic desert formation in Daisyworld.

    PubMed

    Ackland, Graeme J; Clark, Michael A; Lenton, Timothy M

    2003-07-01

    Feedback between life and its environment is ubiquitous but the strength of coupling and its global implications remain hotly debated. Abrupt changes in the abundance of life for small changes in forcing provide one indicator of regulation, for example, when vegetation-climate feedback collapses in the formation of a desert. Here we use a two-dimensional "Daisyworld" model with curvature to show that catastrophic collapse of life under gradual forcing provides a testable indicator of environmental feedback. When solar luminosity increases to a critical value, a desert forms across a wide band of the planet. The scale of collapse depends on the strength of feedback. The efficiency of temperature regulation is limited by mutation rate in an analogous manner to the limitation of adaptive fitness in evolutionary theories. The final state of the system emerging from single-site rules can be described by two global quantities: optimization of temperature regulation and maximization of diversity, which are mathematically analogous to energy and entropy in thermodynamics.

  20. Parasailing fatalities in southwest Florida.

    PubMed

    Wolf, Barbara C; Harding, Brett E

    2009-12-01

    Parasailing is a recreational sport that is generally considered to be of little risk to the participants. Typically, the passenger launches from a motorboat with a specially designed winch that pulls him or her back to the boat at the end of the ride. The sport is not regulated at the federal, state, or county level. There have been few reports of injuries to parasailors. Additionally, there have been only 2 fatalities reported to the United States Coast Guard in a 10-year review. We report the details of these 2 deaths, those of a mother and daughter riding in a tandem parasail, which occurred on Fort Myers Beach in 2001, as well as an additional case of a parasailing fatality that occurred in southwest Florida in 1999. These cases illustrate the injuries seen in such fatalities and the hazards posed by adverse weather conditions and faulty equipment, as well as the impairment of passenger judgment by drugs and/or alcohol.

  1. Thermal regime of the Escalante Desert, Utah, with an analysis of the the Newcastle Geothermal System

    SciTech Connect

    Chapman, D.S.; Clement, M.D.; Mase, C.W.

    1981-12-10

    Twenty-five new heat flow measurements are presented for the Escalante Desert region within the Great Basin of the wester United States. Heat flow, excluding geothermal areas, ranges from 43 to 350 mW m/sup -2/, but much of the variability may be caused by deeply circulating groundwater redistributing the regional flux. A subset of 10 sites drilled specifically to characterize the heat flow of the region yielded a mean of 100 mW m/sup -2/ with a standard deviation of 22 mW m/sup -2/. A comparison of thermal conductivities of solid cylindrical discs and rock chips (rhyolite to andesite tuffs) confirmed the importance of porosity corrections to thermal conductivity measurements. A 'blind' geothermal system southwest of Newastle, Utah, situated within the Escalante Desert, has also been studied. Temperature Desert, has also been studied. Temperatures of 110/sup 0/C are observed only 75 m below the ground surface. Heat flow results from 11 drillholes in this region yield values between 163 and 3065 mW m/sup -2/. The 500 mW m/sup -2/ contour encloses an area of 9.4 km/sup 2/. By integrating the excess heat flux (above background) over the thermal anomaly, we deduce a thermal power loss of 12.8 MW for this geothermal system, which corresponds to a subsurface water discharge of 32 kg s/sup -1/.

  2. Thermal and water relations of desert beetles.

    PubMed

    Cloudsley-Thompson, J L

    2001-11-01

    The physical problems that living organisms have to contend with in hot deserts are primarily extremes of temperature, low humidity, shortage or absence of free water, and the environmental factors that accentuate these--such as strong winds, sand-storms, lack of shade, rocky and impenetrable soils. Climatic factors are particularly important to smaller animals such as arthropods on account of their relatively enormous surface to volume ratios. Nevertheless, beetles (especially Tenebrionidae and, to a lesser extent, Chrysomelidae) are among the most successful animals of the desert, and are often the only ones to be seen abroad during the day. Similar physical problems are experienced by insects in all terrestrial biomes, but they are much enhanced in the desert. Although climatic extremes are often avoided by burrowing habits coupled with circadian and seasonal activity rhythms, as well as reproductive phenology, several species of desert beetle are nevertheless able to withstand thermal extremes that would rapidly cause the death of most other arthropods including insects. The reactions of desert beetles to heat are largely behavioural whilst their responses to water shortage are primarily physiological. The effects of coloration are not discussed. In addition to markedly low rates of transpiration, desert beetles can also withstand a considerable reduction in the water content of their tissues. The study of desert beetles is important because it illustrates many of the solutions evolved by arthropods to the problems engendered, in an extreme form, by life in all terrestrial environments.

  3. Thermal and water relations of desert beetles

    NASA Astrophysics Data System (ADS)

    Cloudsley-Thompson, J.

    2001-11-01

    The physical problems that living organisms have to contend with in hot deserts are primarily extremes of temperature, low humidity, shortage or absence of free water, and the environmental factors that accentuate these - such as strong winds, sand-storms, lack of shade, rocky and impenetrable soils. Climatic factors are particularly important to smaller animals such as arthropods on account of their relatively enormous surface to volume ratios. Nevertheless, beetles (especially Tenebrionidae and, to a lesser extent, Chrysomelidae) are among the most successful animals of the desert, and are often the only ones to be seen abroad during the day. Similar physical problems are experienced by insects in all terrestrial biomes, but they are much enhanced in the desert. Although climatic extremes are often avoided by burrowing habits coupled with circadian and seasonal activity rhythms, as well as reproductive phenology, several species of desert beetle are nevertheless able to withstand thermal extremes that would rapidly cause the death of most other arthropods including insects. The reactions of desert beetles to heat are largely behavioural whilst their responses to water shortage are primarily physiological. The effects of coloration are not discussed. In addition to markedly low rates of transpiration, desert beetles can also withstand a considerable reduction in the water content of their tissues. The study of desert beetles is important because it illustrates many of the solutions evolved by arthropods to the problems engendered, in an extreme form, by life in all terrestrial environments.

  4. Competing Interests and Concerns in the Rio Grande Basin: Mountain Hydrology, Desert Ecology, Climate Change, and Population Growth

    NASA Astrophysics Data System (ADS)

    Rango, A.

    2004-12-01

    In the mountainous American Southwest, the Rio Grande basin is a prime example of how conflicts, misconceptions, and competition regarding water can arise in arid and semi-arid catchments. Much of the Rio Grande runoff originates from snow fields in the San Juan Mountains of southern Colorado and the Sangre De Cristo Mountains of northern New Mexico, far from population centers. Large and rapidly growing cities, like Albuquerque, Las Cruces, El Paso, and Juarez, are located along the Rio Grande where it flows through the Chihuahuan Desert, the largest desert in North America(two NSF Long Term Ecological Research sites are located in the desert portion of the basin). As a result, the importance of snowmelt, which makes up 50-75% or more of the total streamflow in sub-basins above Elephant Butte Reservoir(in south central New Mexico) is hardly known to the general public. Streamflow below Elephant Butte Reservoir is rainfall driven and very limited, with the lower basin receiving only 170-380 mm of precipitation annually, most of it occurring during the months of July-September. Extreme events, such as drought and flooding, are not unusual in arid basins, and they are of increasing concern with regard to changes in frequency of such events under the impending conditions of climate change. Current water demands in the basin already exceed the water supply by 15% or more, so streamflow forecasts(especially from snowmelt runoff) are extremely valuable for efficient water management as well as for proper apportionment of water between Colorado, New Mexico, and Texas under the Rio Grande Compact of 1938 and between the U.S. and Mexico under the Treaty of 1906. Other demands on the water supply include Indian water rights, flood regulation, irrigated agriculture, municipal and industrial demands, water quality, riverine and riparian habitat protection, endangered and threatened species protection, recreation, and hydropower. To assess snow accumulation and cover and to

  5. Wildfire and invasive plants in American deserts: a special feature

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Society for Range Management (SRM) and 26 partners hosted a special conference in Reno, Nevada in December of 2008 in response to the need to provide information for the management of native rangelands in the face of challenges posed by the interactions of invasive plants and wildfire. SRM hoste...

  6. Effects of desert wildfires on desert tortoise (Gopherus agassizii) and other small vertebrates

    USGS Publications Warehouse

    Esque, T.C.; Schwalbe, C.R.; DeFalco, L.A.; Duncan, R.B.; Hughes, T.J.

    2003-01-01

    We report the results of standardized surveys to determine the effects of wildfires on desert tortoises (Gopherus agassizii) and their habitats in the northeastern Mojave Desert and northeastern Sonoran Desert. Portions of 6 burned areas (118 to 1,750 ha) were examined for signs of mortality of vertebrates. Direct effects of fire in desert habitats included animal mortality and loss of vegetation cover. A range of 0 to 7 tortoises was encountered during surveys, and live tortoises were found on all transects. In addition to desert tortoises, only small (<1 kg) mammals and reptiles (11 taxa) were found dead on the study areas. We hypothesize that indirect effects of fire on desert habitats might result in changes in the composition of diets and loss of vegetation cover, resulting in an increase in predation and loss of protection from temperature extremes. These changes in habitat also might cause changes in vertebrate communities in burned areas.

  7. Microphytic crusts: 'topsoil' of the desert

    USGS Publications Warehouse

    Belnap, Jayne

    1990-01-01

    Deserts throughout the world are the home of microphytic, or cryptogamic, crusts. These crusts are dominated by cyanobacteria, previously called blue-green algae, and also include lichens, mosses, green algae, microfungi and bacteria. They are critical components of desert ecosystems, significantly modifying the surfaces on which they occur. In the cold deserts of the Colorado Plateau (including parts of Utah, Arizona, Colorado, and New Mexico), these crusts are extraordinarily well-developed, and may represent 70-80% of the living ground cover.

  8. Nonlinear responses of desert shrubs to episodic rainfall events

    NASA Astrophysics Data System (ADS)

    Ogle, K.; Reynolds, J. F.

    2001-12-01

    The physiological responses of desert shrubs to rapidly varying soil and atmospheric water status are equivocal. While much of the wide variations in observed responses in gas exchange and plant water potential can be readily attributed to nonlinear plant-soil-atmosphere couplings, there is a paucity of data to quantify these behaviors in the field. This motivated us to conduct an integrated field and modeling study on Larrea tridentata, the dominant shrub of North American warm deserts. We monitored photosynthesis, stomatal behavior, and water potential of 16 individual shrubs exposed to natural and simulated rainfall during two growing seasons at a field site in southern New Mexico. We use these field data to develop a new photosynthesis (A) model that explicitly links internal CO2 (Ci) and stomatal conductance (g). A threshold response is assumed for instantaneous g such that stomata operate at their maximum g (gmax) for low vapor pressure deficits (VPD); thereafter, g decreases nonlinearly with increasing VPD. Predawn water potential and growing temperature interact with VPD to affect g and gmax. Ci is a linear function of g and the intercept is the minimum achievable Ci, which varies with temperature and light intensity. This model is able to reproduce Larrea's responses to episodic soil and atmospheric water availability, capturing the large diurnal and seasonal fluctuations in A, g, and Ci. We use this model to show that the many conflicting conclusions regarding desert shrub responses to rainfall are explained by the lack of sufficient field data and by several key nonlinear plant-soil-atmosphere couplings.

  9. Response of the North American monsoon to regional changes in ocean surface temperature

    USGS Publications Warehouse

    Barron, John A.; Metcalfe, Sarah E.; Addison, Jason A.

    2012-01-01

    The North American monsoon (NAM), an onshore wind shift occurring between July and September, has evolved in character during the Holocene largely due to changes in Northern Hemisphere insolation. Published paleoproxy and modeling studies suggest that prior to ∼8000 cal years BP, the NAM affected a broader region than today, extending westward into the Mojave Desert of California. Holocene proxy SST records from the Gulf of California (GoC) and the adjacent Pacific provide constraints for this changing NAM climatology. Prior to ∼8000 cal years BP, lower GoC SSTs would not have fueled northward surges of tropical moisture up the GoC, which presently contribute most of the monsoon precipitation to the western NAM region. During the early Holocene, the North Pacific High was further north and SSTs in the California Current off Baja California were warmer, allowing monsoonal moisture flow from the subtropical Pacific to take a more direct, northwesterly trajectory into an expanded area of the southwestern U.S. west of 114°W. A new upwelling record off southwest Baja California reveals that enhanced upwelling in the California Current beginning at ∼7500 cal year BP may have triggered a change in NAM climatology, focusing the geographic expression of NAM in the southwest USA into its modern core region east of ∼114°W, in Arizona and New Mexico. Holocene proxy precipitation records from the southwestern U.S. and northwestern Mexico, including lakes, vegetation/pollen, and caves are reviewed and found to be largely supportive of this hypothesis of changing Holocene NAM climatology.

  10. Response of the North American monsoon to regional changes in ocean surface temperature

    NASA Astrophysics Data System (ADS)

    Barron, John A.; Metcalfe, Sarah E.; Addison, Jason A.

    2012-09-01

    The North American monsoon (NAM), an onshore wind shift occurring between July and September, has evolved in character during the Holocene largely due to changes in Northern Hemisphere insolation. Published paleoproxy and modeling studies suggest that prior to ˜8000 cal years BP, the NAM affected a broader region than today, extending westward into the Mojave Desert of California. Holocene proxy SST records from the Gulf of California (GoC) and the adjacent Pacific provide constraints for this changing NAM climatology. Prior to ˜8000 cal years BP, lower GoC SSTs would not have fueled northward surges of tropical moisture up the GoC, which presently contribute most of the monsoon precipitation to the western NAM region. During the early Holocene, the North Pacific High was further north and SSTs in the California Current off Baja California were warmer, allowing monsoonal moisture flow from the subtropical Pacific to take a more direct, northwesterly trajectory into an expanded area of the southwestern U.S. west of 114°W. A new upwelling record off southwest Baja California reveals that enhanced upwelling in the California Current beginning at ˜7500 cal year BP may have triggered a change in NAM climatology, focusing the geographic expression of NAM in the southwest USA into its modern core region east of ˜114°W, in Arizona and New Mexico. Holocene proxy precipitation records from the southwestern U.S. and northwestern Mexico, including lakes, vegetation/pollen, and caves are reviewed and found to be largely supportive of this hypothesis of changing Holocene NAM climatology.

  11. A long-term vegetation history of the Mojave-Colorado Desert ecotone at Joshua Tree National Park

    USGS Publications Warehouse

    Holmgren, Camille A.; Betancourt, Julio L.; Rylander, Kate A.

    2010-01-01

    Thirty-eight dated packrat middens were collected from upper desert (930-1357?m) elevations within Joshua Tree National Park near the ecotone between the Mojave Desert and Colorado Desert, providing a 30?ka record of vegetation change with remarkably even coverage for the last 15?ka. This record indicates that vegetation was relatively stable, which may reflect the lack of invasion by extralocal species during the late glacial and the early establishment and persistence of many desert scrub elements. Many of the species found in the modern vegetation assemblages were present by the early Holocene, as indicated by increasing S?renson\\'s Similarity Index values. C4 grasses and summer-flowering annuals arrived later at Joshua Tree National Park in the early Holocene, suggesting a delayed onset of warm-season monsoonal precipitation compared to other Sonoran Desert and Chihuahuan Desert localities to the east, where summer rains and C4 grasses persisted through the last glacial?interglacial cycle. This would suggest that contemporary flow of monsoonal moisture into eastern California is secondary to the core processes of the North American Monsoon, which remained intact throughout the late Quaternary. In the Holocene, northward displacement of the jet stream, in both summer and winter, allowed migration of the subtropical ridge as far north as southern Idaho and the advection of monsoonal moisture both westward into eastern California and northward into the southern Great Basin and Colorado Plateau. Copyright 2009 John Wiley & Sons, Ltd.

  12. Consequences of long-term changes in seasonal precipitation for the biochemistry of photosynthesis in dominant desert shrubs and grasses

    NASA Astrophysics Data System (ADS)

    Bentley, L. P.; Ogle, K.; Loik, M. E.; Huxman, T. E.; Smith, S. D.; Tissue, D.

    2011-12-01

    Alterations in seasonal precipitation have been demonstrated to have short-term effects on biochemical limitations to photosynthesis, but longer-term effects on plant biochemistry are generally unknown. This study explores the long-term impacts of altered precipitation on the photosynthetic biochemistry of seven dominant desert plants. Seasonal precipitation was experimentally manipulated (addition and/or exclusion) for 5-6 years in four North American deserts prior to a 2-year campaign of photosynthetic measurements. Photosynthetic response curve data were analyzed via a novel hierarchical Bayesian model that enabled the estimation of biochemical limitations to photosynthesis in C3 and C4 plants, while simultaneously incorporating precipitation treatment effects. In the Chihuahuan Desert, an increase in both summer and winter precipitation increased biochemical efficiency in a C3 woody monocot. In the Sonoran Desert, increased winter precipitation increased biochemical efficiency in a C4 non-native grass. Precipitation treatment effects were lacking in the Mojave and Great Basin Deserts, perhaps due to low summer precipitation in these deserts. Seasonal precipitation differentially affects plant- and species-level carbon dynamics over the long-term due to the timing of precipitation and the interaction of precipitation with nitrogen dynamics. Our results emphasize the importance of studying longer-term biochemical responses to changes in environmental conditions because they may not reflect short-term stomatal responses.

  13. Psychological Distress Among Elderly Mexican Americans and Anglos.

    ERIC Educational Resources Information Center

    Markides, Kyriakos S.; And Others

    Psychological distress is investigated in a sample of elderly Mexican Americans and Anglos residing in a four-census tract area in southwest San Antonio. Comparisons of the two ethnic groups using the Computer Derived Mental Health Rating as the measure of psychological distress show that Mexican Americans exhibit more distress than Anglos. This…

  14. This Proud Land, A Unit in Native American Studies.

    ERIC Educational Resources Information Center

    Noe, Sally W.; Wright, Gregory, Ed.

    The American Indians of the Southwest--their history and culture from ancient to modern times--are the focal point of this resource manual based on an American history course developed at Gallup High School, Gallup, New Mexico. The course covers ancient culture and migrations of the Indian tribes now inhabiting New Mexico and the coming of Spanish…

  15. Desert Dust and Monsoon Rain

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.; Kim, Kyu-Myong

    2014-01-01

    For centuries, inhabitants of the Indian subcontinent have know that heavy dust events brought on by strong winds occur frequently in the pre-monsoon season, before the onset of heavy rain. Yet scientists have never seriously considered the possibility that natural dust can affect monsoon rainfall. Up to now, most studies of the impacts of aerosols on Indian monsoon rainfall have focused on anthropogenic aerosols in the context of climate change. However, a few recent studies have show that aerosols from antropogenic and natural sources over the Indian subcontinent may affect the transition from break to active monsoon phases on short timescales of days to weeks. Writing in Nature Geoscience, Vinoj and colleagues describe how they have shown that desert dust aerosols over the Arabian Sea and West Asia can strenghten the summer monsoon over the Indial subcontinent in a matter of days.

  16. Desert Dust Satellite Retrieval Intercomparison

    NASA Technical Reports Server (NTRS)

    Carboni, E.; Thomas, G. E.; Sayer, A. M.; Siddans, R.; Poulsen, C. A.; Grainger, R. G.; Ahn, C.; Antoine, D.; Bevan, S.; Braak, R.; Brindley, H.; DeSouza-Mchado, S.; Deuze, J. L.; Diner, D.; Ducos, F.; Grey, W.; Hsu, C.; Kalashnikova, O. V.; Kahn, R.; North, P. R. J.; Salustro, C.; Smith, A.; Tanre, D.; Torres, O.; Veihelmann, B.

    2012-01-01

    This work provides a comparison of satellite retrievals of Saharan desert dust aerosol optical depth (AOD) during a strong dust event through March 2006. In this event, a large dust plume was transported over desert, vegetated, and ocean surfaces. The aim is to identify and understand the differences between current algorithms, and hence improve future retrieval algorithms. The satellite instruments considered are AATSR, AIRS, MERIS, MISR, MODIS, OMI, POLDER, and SEVIRI. An interesting aspect is that the different algorithms make use of different instrument characteristics to obtain retrievals over bright surfaces. These include multi-angle approaches (MISR, AATSR), polarisation measurements (POLDER), single-view approaches using solar wavelengths (OMI, MODIS), and the thermal infrared spectral region (SEVIRI, AIRS). Differences between instruments, together with the comparison of different retrieval algorithms applied to measurements from the same instrument, provide a unique insight into the performance and characteristics of the various techniques employed. As well as the intercomparison between different satellite products, the AODs have also been compared to co-located AERONET data. Despite the fact that the agreement between satellite and AERONET AODs is reasonably good for all of the datasets, there are significant differences between them when compared to each other, especially over land. These differences are partially due to differences in the algorithms, such as as20 sumptions about aerosol model and surface properties. However, in this comparison of spatially and temporally averaged data, at least as significant as these differences are sampling issues related to the actual footprint of each instrument on the heterogeneous aerosol field, cloud identification and the quality control flags of each dataset.

  17. Desert potholes: Ephemeral aquatic microsystems

    USGS Publications Warehouse

    Chan, M.A.; Moser, K.; Davis, J.M.; Southam, G.; Hughes, K.; Graham, T.

    2005-01-01

    An enigma of the Colorado Plateau high desert is the "pothole", which ranges from shallow ephemeral puddles to deeply carved pools. The existence of prokaryotic to eukaryotic organisms within these pools is largely controlled by the presence of collected rainwater. Multivariate statistical analysis of physical and chemical limnologic data variables measured from potholes indicates spatial and temporal variations, particularly in water depth, manganese, iron, nitrate and sulfate concentrations and salinity. Variation in water depth and salinity are likely related to the amount of time since the last precipitation, whereas the other variables may be related to redox potential. The spatial and temporal variations in water chemistry affect the distribution of organisms, which must adapt to daily and seasonal extremes of fluctuating temperature (0-60 ??C), pH changes of as much as 5 units over 12 days, and desiccation. For example, many species become dormant when potholes dry, in order to endure intense heat, UV radiation, desiccation and freezing, only to flourish again upon rehydration. But the pothole organisms also have a profound impact on the potholes. Through photosynthesis and respiration, pothole organisms affect redox potential, and indirectly alter the water chemistry. Laboratory examination of dried biofilm from the potholes revealed that within 2 weeks of hydration, the surface of the desiccated, black biofilm became green from cyanobacterial growth, which supported significant growth in heterotrophic bacterial populations. This complex biofilm is persumably responsible for dissolving the cement between the sandstone grains, allowing the potholes to enlarge, and for sealing the potholes, enabling them to retain water longer than the surrounding sandstone. Despite the remarkable ability of life in potholes to persist, desert potholes may be extremely sensitive to anthropogenic effects. The unique limnology and ecology of Utah potholes holds great scientific

  18. Satellite Observations of Desert Dust-induced Himalayan Snow Darkening

    NASA Technical Reports Server (NTRS)

    Gautam, Ritesh; Hsu, N. Christina; Lau, William K.-M.; Yasunari, Teppei J.

    2013-01-01

    The optically thick aerosol layer along the southern edge of the Himalaya has been subject of several recent investigations relating to its radiative impacts on the South Asian summer monsoon and regional climate forcing. Prior to the onset of summer monsoon, mineral dust from southwest Asian deserts is transported over the Himalayan foothills on an annual basis. Episodic dust plumes are also advected over the Himalaya, visible as dust-laden snow surface in satellite imagery, particularly in western Himalaya. We examined spectral surface reflectance retrieved from spaceborne MODIS observations that show characteristic reduction in the visible wavelengths (0.47 nm) over western Himalaya, associated with dust-induced solar absorption. Case studies as well as seasonal variations of reflectance indicate a significant gradient across the visible (0.47 nm) to near-infrared (0.86 nm) spectrum (VIS-NIR), during premonsoon period. Enhanced absorption at shorter visible wavelengths and the resulting VIS-NIR gradient is consistent with model calculations of snow reflectance with dust impurity. While the role of black carbon in snow cannot be ruled out, our satellite-based analysis suggests the observed spectral reflectance gradient dominated by dust-induced solar absorption during premonsoon season. From an observational viewpoint, this study underscores the importance of mineral dust deposition toward darkening of the western Himalayan snow cover, with potential implications to accelerated seasonal snowmelt and regional snow albedo feedbacks.

  19. Profile of the Mexican American Woman.

    ERIC Educational Resources Information Center

    Cotera, Martha

    The second largest group of minority women in the U.S., Mexican American women share multitudinous histories, vast differences in lifestyles, experiences and realities. A Chicana may have recently arrived from Mexico, or her ancestors may have been in the Southwest since 1520 (or before) or in the Midwest since the 1880's. She may be rural, urban,…

  20. Power lines: Urban space, energy development and the making of the modern Southwest

    NASA Astrophysics Data System (ADS)

    Needham, Todd Andrew

    "Power Lines: Urban Space, Energy Development, and the Making of the Modern Southwest" explores the social and environmental transformation of the postwar Southwest and the resulting disputes between urban boosters, federal officials, Native Americans, and environmental activists. The dissertation focuses on the infrastructure built to provide the burgeoning populations of Phoenix, Los Angeles, and other Southwestern cities with electricity. This infrastructure allowed metropolitan boosters in the Southwest to attract Cold War defense manufacturing and to build a new suburban landscape even as industrialization on Indian lands provided electricity for those landscapes. Tracing the transition of electrical generation from a dispersed geography relying on local resources to a centralized geography utilizing primarily coal from Navajo land, "Power Lines" demonstrates the increasing centrality of Indian lands and labor to the metropolitan Southwest. Paying close attention to these networks reveals the far-reaching changes caused by postwar metropolitan growth. "Power Lines" challenges understandings of urban space that neglect the material resources that allow cities to "live." As the nation's cities and suburbs became increasingly energy-intensive, electrical utilities reached deep into the metropolitan periphery, transforming landscapes hundreds of miles from city centers into urban space. The construction of the new "geography of power" in the Southwest also reflects the impact of growth liberalism on postwar growth, as federal money funded suburban, manufacturing, and infrastructure developments. This pursuit of growth produced new political struggles, both as the development of energy resources conflicted with emerging environmentalist sensibilities and as American Indians increasingly resented the industrialization of their land for the benefit of others. By the 1970s, the simultaneous pursuit and criticism of growth came to define the modern Southwest. The

  1. 2011 Desert RATS Sights and Sounds

    NASA Video Gallery

    Watch scenes from the 2011 Desert Research and Technology Studies (RATS) analog field test, as NASA scientists and engineers drive the Space Exploration Vehicle, assemble equipment in the Habitat D...

  2. Giant viruses of the Kutch Desert.

    PubMed

    Kerepesi, Csaba; Grolmusz, Vince

    2016-03-01

    The Kutch Desert (Great Rann of Kutch, Gujarat, India) is a unique ecosystem: in the larger part of the year it is a hot, salty desert that is flooded regularly in the Indian monsoon season. In the dry season, the crystallized salt deposits form the "white desert" in large regions. The first metagenomic analysis of the soil samples of Kutch was published in 2013, and the data were deposited in the NCBI Sequence Read Archive. At the same time, the sequences were analyzed phylogenetically for prokaryotes, especially for bacteria. In the present work, we identified DNA sequences of recently discovered giant viruses in the soil samples from the Kutch Desert. Since most giant viruses have been discovered in biofilms in industrial cooling towers, ocean water, and freshwater ponds, we were surprised to find their DNA sequences in soil samples from a seasonally very hot and arid, salty environment.

  3. Desert R.A.T.S. 2011

    NASA Video Gallery

    Desert Research And Technology Studies (D-R.A.T.S) kicks off an exciting new year of field testing. The crew is back in action, testing communication scenarios for near-Earth asteroids, and two new...

  4. Giant viruses of the Kutch Desert.

    PubMed

    Kerepesi, Csaba; Grolmusz, Vince

    2016-03-01

    The Kutch Desert (Great Rann of Kutch, Gujarat, India) is a unique ecosystem: in the larger part of the year it is a hot, salty desert that is flooded regularly in the Indian monsoon season. In the dry season, the crystallized salt deposits form the "white desert" in large regions. The first metagenomic analysis of the soil samples of Kutch was published in 2013, and the data were deposited in the NCBI Sequence Read Archive. At the same time, the sequences were analyzed phylogenetically for prokaryotes, especially for bacteria. In the present work, we identified DNA sequences of recently discovered giant viruses in the soil samples from the Kutch Desert. Since most giant viruses have been discovered in biofilms in industrial cooling towers, ocean water, and freshwater ponds, we were surprised to find their DNA sequences in soil samples from a seasonally very hot and arid, salty environment. PMID:26666442

  5. Microbial Fossils Detected in Desert Varnish

    NASA Astrophysics Data System (ADS)

    Flood, B. E.; Allen, C.; Longazo, T.

    2003-03-01

    Desert varnish, a mixture of clays, Mn-oxides, and Fe-oxides, is a potential terrestrial analogue to Martian hematite. A scanning electron microscopic examination of samples from Pilbara, Australia revealed evidence of microbial fossilization.

  6. Magnetic Analysis Techniques Applied to Desert Varnish

    NASA Astrophysics Data System (ADS)

    Schmidgall, E. R.; Moskowitz, B. M.; Dahlberg, E. D.; Kuhlman, K. R.

    2003-03-01

    A vibrating sample magnetometer (VSM) and radio frequency superconducting quantum interference device (RF SQUID) have been used to measure the properties of magnetic carriers in samples of black and red rock varnish from the Mojave Desert.

  7. Problems with the North American Monsoon in CMIP/IPCC GCM Precipitation

    NASA Astrophysics Data System (ADS)

    Schiffer, N. J.; Nesbitt, S. W.

    2011-12-01

    Successful water management in the Desert Southwest and surrounding areas hinges on anticipating the timing and distribution of precipitation. IPCC AR4 models predict a more arid climate, more extreme precipitation events, and an earlier peak in springtime streamflow in the North American Monsoon region as the area warms. This study aims to assess the summertime skill with which general circulation models (GCMs) simulate precipitation and related dynamics over this region, a necessary precursor to reliable hydroclimate projections. Thirty-year climatologies of several GCMs in the third and fifth Climate Model Intercomparison Projects (CMIP) are statistically evaluated against each other and observed climatology for their skill in representing the location, timing, variability, character, and large-scale forcing of precipitation over the southwestern United States and northwestern Mexico. The results of this study will lend greater credence to more detailed, higher resolution studies, based on the CMIP and IPCC models, of the region's future hydrology. Our ultimate goal is to provide guidance such that decision-makers can plan future water management with more confidence.

  8. Trona resources in southwest Wyoming

    USGS Publications Warehouse

    Dyni, J.R.; Wiig, S.V.; Grundy, W.D.

    1995-01-01

    Bedded trona (Na2CO3??NaHCO3??2H2O) in the lacustrine Green River Formation of Eocene age in the Green River Basin, southwest Wyoming, constitutes the largest known resource of natural sodium carbonate in the world. In this study, 116 gigatons (Gt) of trona ore are estimated to be present in 22 beds, ranging from 1.2 to 11 meters (m) in thickness. Of this total, 69 Gt of trona ore are estimated to be in beds containing less than 2 percent halite and 47 Gt in beds containing 2 or more percent halite. These 22 beds underlie areas of about 130 to more than 2,000 km2 at depths ranging from about 200 m to more than 900 m below the surface. The total resource of trona ore in the basin for which drilling information is available is estimated to be about 135 Gt. Underveloped trona beds in the deeper southern part of the basin may be best developed by solution mining. Additional unevaluated sodium carbonate resources are present in disseminated shortite (Na2CO3??2CaCO3) in strata interbedded with the trona and in shallow sodium carbonate brines in the northeast part of the basin. Estimates of the shortite and brine resources were not made. ?? 1995 Oxford University Press.

  9. Desert varnish: an environmental recorder for Mars

    NASA Astrophysics Data System (ADS)

    Perry, Randall S.; Sephton, Mark A.

    2006-08-01

    With the prospect of a Mars Sample Return mission in the next two decades, attention is now focusing on the types of samples that would be most useful for returning to Earth for laboratory analysis. Recent data on desert varnish reveal that laminated coatings on rocks from extreme environments are a passive recorder of past and present environments. Martian desert varnish would contain a chronology of the martian setting, perhaps extending back to a wetter and more biologically active period.

  10. Impact of the Desert Dust on the Summer Monsoon System over Southwestern North America

    SciTech Connect

    Zhao, Chun; Liu, Xiaohong; Leung, Lai-Yung R.

    2012-04-24

    The radiative forcing of dust emitted from the Southwest United States (US) deserts and its impact on monsoon circulation and precipitation over the North America monsoon (NAM) region are simulated using a coupled meteorology and aerosol/chemistry model (WRF-Chem) for 15 years (1995-2009). During the monsoon season, dust has a cooling effect (-0.90 W m{sup -2}) at the surface, a warming effect (0.40 W m{sup -2}) in the atmosphere, and a negative top-of-the-atmosphere (TOA) forcing (-0.50 W m{sup -2}) over the deserts on 24-h average. Most of the dust emitted from the deserts concentrates below 800 hPa and accumulates over the western slope of the Rocky Mountains and Mexican Plateau. The absorption of shortwave radiation by dust heats the lower atmosphere by up to 0.5 K day{sup -1} over the western slope of the Mountains. Model sensitivity simulations with and without dust for 15 summers (June-July-August) show that dust heating of the lower atmosphere over the deserts strengthens the low-level southerly moisture fluxes on both sides of the Sierra Madre Occidental. It also results in an eastward migration of NAM-driven moisture convergence over the western slope of the Mountains. These monsoonal circulation changes lead to a statistically significant increase of precipitation by up to {approx}40% over the eastern slope of the Mountains (Arizona-New Mexico-Texas regions). This study highlights the interaction between dust and the NAM system and motivates further investigation of possible dust feedback on monsoon precipitation under climate change and the megadrought conditions projected for the future.

  11. Geomorphic control of radionuclide diffusion in desert soils

    USGS Publications Warehouse

    Pelletier, J.D.; Harrington, C.D.; Whitney, J.W.; Cline, M.; DeLong, S.B.; Keating, G.; Ebert, T.K.

    2005-01-01

    Diffusion is a standard model for the vertical migration of radionuclides in soil profiles. Here we show that diffusivity values inferred from fallout 137CS profiles in soils on the Fortymile Wash alluvial fan, Nye County, Nevada, have a strong inverse correlation with the age of the geomorphic surface. This result suggests that radionuclide-bound particles are predominantly transported by infiltration rather than by bulk-mixing processes such as wetting/ drying, freeze/thaw, and bioturbation. Our results provide a preliminary basis for using soil-geomorphic mapping, point-based calibration data, and the diffusion model to predict radionuclide trans desert soils within a pedotransfer-function approach. Copyright 2005 by the American Geophysical Union.

  12. Incorporating Mexican American History and Culture into the Social Studies Classroom.

    ERIC Educational Resources Information Center

    Escamilla, Kathy

    Although Mexican Americans are the fastest growing ethnic group in the United States, their history and literature are seldom taught in American classrooms. A study of over 3,000 high school sophomores in the Southwest revealed that neither Anglos nor Hispanics were aware of the contributions of Mexican Americans. Incorporating Mexican American…

  13. Still "Unfinished Education": Latino Students Forty Years after the Mexican American Education Study

    ERIC Educational Resources Information Center

    Madrigal-Gonzalez, Lizely

    2012-01-01

    The onus of this dissertation was to evaluate the educational conditions of Mexican American students forty years after the "Mexican American Education Study" published a six-volume study detailing the findings of the "Mexican American Education Study" (1970-1974). The "MAES" study focused on five southwest states…

  14. Folk medicine in the Southwest. Myths and medical facts.

    PubMed

    Trotter, R T

    1985-12-01

    The three folk illnesses described in this article--caida de mollera, susto, and empacho--can all be linked to recognized biologic conditions and therefore cannot be analyzed solely on the basis of sociocultural factors. Clearly, it would be a mistake to continue ignoring these syndromes in the Southwest on the assumption that they are "all in the mind" of Mexican-American patients. They must be assessed from the view that they are culturally different labels for serious medical conditions (eg, caida de mollera), that they are useful screening labels for patients with high disease loads (eg, susto), or that they are harmless in and of themselves but their treatment may have significant medical consequences (eg, empacho).

  15. 1. Historic American Buildings Survey, Bill Engdahl for HedrichBlessing, Photographers, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, Bill Engdahl for Hedrich-Blessing, Photographers, February, 1979 DISTANCE VIEW FROM SOUTHWEST. - Field-Pacheco Complex, 1049 East Monroe Street, Brownsville, Cameron County, TX

  16. 5. Historic American Buildings Survey, Bill Engdahl for HedrichBlessing, Photographers, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Historic American Buildings Survey, Bill Engdahl for Hedrich-Blessing, Photographers, February, 1979 PEDIMENT SIGN ABOVE BALCONY SOUTHWEST FACADE. - Field-Pacheco Complex, 1049 East Monroe Street, Brownsville, Cameron County, TX

  17. 2. Historic American Buildings Survey, Bill Engdahl for HedrichBlessing, Photographers, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey, Bill Engdahl for Hedrich-Blessing, Photographers, February, 1979 SEVEN-BAY FACADE VIEW FROM SOUTHWEST. - Field-Pacheco Complex, 1049 East Monroe Street, Brownsville, Cameron County, TX

  18. 4. Historic American Buildings Survey John P. O'Neill, Photographer March ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey John P. O'Neill, Photographer March 3, 1937 LOOKING NORTHEAST FROM SOUTHWEST CORNER OF PRINCIPAL STRUCTURE (Note Treasure Hunters' Holes) - Mission San Cosme del Tucson, Menlo Park, Tucson, Pima County, AZ

  19. 4. Historic American Buildings Survey Ray Malinowski, Photographer JulyAugust 1968 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey Ray Malinowski, Photographer July-August 1968 UNDATED PHOTOCOPY, SOUTH (FRONT) FACADE, LOOKING FROM SOUTHWEST - St. Michael's Creole Benevolent Association, 410 East Government Street, Pensacola, Escambia County, FL

  20. 2. Historic American Buildings Survey Ray Malinowski, Photographer JulyAugust 1968 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey Ray Malinowski, Photographer July-August 1968 SOUTHWEST VIEW - Dorothy Walton House, 221 East Zaragoza Street (moved from 137 West Romana Street), Pensacola, Escambia County, FL

  1. 5. Historic American Buildings Survey, Bill Engdahl for HedrichBlessing, Photographers, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Historic American Buildings Survey, Bill Engdahl for Hedrich-Blessing, Photographers, February, 1979 MAIN ENTRANCE, SOUTHWEST FACADE. - Cameron County Courthouse, 1150 East Madison Street, Brownsville, Cameron County, TX

  2. 1. Historic American Buildings Survey, E.J. Stein, Photographer, October 1927, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, E.J. Stein, Photographer, October 1927, VIEW FROM SOUTHWEST, Gift of New York State Department of Education. - Shaker Ministry's House, Watervliet Shaker Road, Colonie Township, Watervliet, Albany County, NY

  3. 2. Historic American Buildings Survey, E.J. Stein, Photographer, November 1927, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey, E.J. Stein, Photographer, November 1927, VIEW FROM SOUTHWEST, Gift of New York State Department of Education. - Shaker Church Family Seed House, Watervliet Shaker Road, Colonie Township, Watervliet, Albany County, NY

  4. 3. Historic American Buildings Survey, E.J. Stein, Photographer, October 1927, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey, E.J. Stein, Photographer, October 1927, VIEW FROM SOUTHWEST, Gift of New York State Department of Education. - Shaker Church Family Washhouse & Canning Factory, Watervliet Shaker Road, Colonie Township, Watervliet, Albany County, NY

  5. 1. Historic American Buildings Survey, E.J. Stein, Photographer, November 1927, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, E.J. Stein, Photographer, November 1927, VIEW FROM SOUTHWEST, Gift of New York State Department of Education. - Shaker Meetinghouse (first), Watervliet Shaker Road, Colonie Township, Watervliet, Albany County, NY

  6. 1. Historic American Buildings Survey, Bill Engdahl for HedrichBlessing, Photographers, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, Bill Engdahl for Hedrich-Blessing, Photographers, February, 1979, 11TH STREET PERSPECTIVE FROM SOUTHWEST. - El Globo Chiquito, 1054 East Monroe Street, Brownsville, Cameron County, TX

  7. 4. Historic American Buildings Survey, Pierre LeBoutillier and Trusten M. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey, Pierre LeBoutillier and Trusten M. Baldwin, Photographers, April, 1960 SOUTHWEST ELEVATION. - King of Prussia Inn, U.S. Route 202 (Upper Merion Township), King of Prussia, Montgomery County, PA

  8. Historic Distrust and the Counseling of American Indians and Alaska Natives.

    ERIC Educational Resources Information Center

    Lockart, Barbetta

    1981-01-01

    Since establishment of trust is crucial to counseling relationships, American Indian distrust of non-Indians must be dealt with for successful counseling. Available from: White Cloud Center, Gaines Hall UOHSC, 840 Southwest Gaines Road, Portland, OR 97201. (CM)

  9. 6. Historic American Buildings Survey Oriana Day Paintings, DeYoung Museum ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Historic American Buildings Survey Oriana Day Paintings, DeYoung Museum San Francisco, California Original: Re-photo: February 1940 VIEW FROM SOUTHWEST - Mission San Antonio de Padua, Hunter Liggett Military Reservation, Jolon, Monterey County, CA

  10. 2. Historic American Buildings Survey From Oriana Day paintings DeYoung ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey From Oriana Day paintings DeYoung Museum, San Francisco Original: 1861-1885 Re-photo: February 1940 VIEW FROM SOUTHWEST - Mission Nuestra Senora de la Soledad, Soledad, Monterey County, CA

  11. Internal and External Adaptation in Army Families: Lessons from Operations Desert Shield and Desert Storm

    ERIC Educational Resources Information Center

    Pittman, Joe F.; Kerpelman, Jennifer L.; McFadyen, Jennifer M.

    2004-01-01

    This study examined 1,064 Army families reunited after a member's deployment for Operation Desert Shield and Operation Desert Storm. Postdeployment outcomes were conceptualized in terms of the "fit" between the family and the demands of Army life, especially the stress of deployment. A structural model was used to test the hypothesized effects of…

  12. HIGH FOLIAR NITROGEN IN DESERT SHRUBS: AN IMPORTANT ECOSYSTEM TRAIT OR DEFECTIVE DESERT DOCTRINE?

    EPA Science Inventory

    Nitrogen concentrations in green and senesced leaves of perennial desert shrubs were compiled from a worldwide literature search to test the validity of the doctrine that desert shrubs produce foliage and leaf litter much richer in nitrogen than that in the foliage of plants from...

  13. Traditional cultural use as a tool for inferring biogeography and provenance: a case study involving painted turtles (Chrysemys picta) and Hopi Native American culture in Arizona, USA

    USGS Publications Warehouse

    Lovich, Jeffrey E.; LaRue, Charles T.; Drost, Charles A.; Arundel, Terence R.

    2014-01-01

    Inferring the natural distribution and native status of organisms is complicated by the role of ancient and modern humans in utilization and translocation. Archaeological data and traditional cultural use provide tools for resolving these issues. Although the painted turtle (Chrysemys picta) has a transcontinental range in the United States, populations in the Desert Southwest are scattered and isolated. This pattern may be related to the fragmentation of a more continuous distribution as a result of climate change after the Pleistocene, or translocation by Native Americans who used turtles for food and ceremonial purposes. Because of these conflicting or potentially confounded possibilities, the distribution and status of C. picta as a native species in the state of Arizona has been questioned in the herpetological literature. We present evidence of a population that once occurred in the vicinity of Winslow, Arizona, far from current remnant populations on the upper Little Colorado River. Members of the Native American Hopi tribe are known to have hunted turtles for ceremonial purposes in this area as far back as AD 1290 and possibly earlier. Remains of C. picta are known from several pueblos in the vicinity including Homol'ovi, Awatovi, and Walpi. Given the great age of records for C. picta in Arizona and the concordance of its fragmented and isolated distribution with other reptiles in the region, we conclude that painted turtles are part of the native fauna of Arizona.

  14. Energy expenditure and efficiency of energy use in rodents: desert and non-desert species.

    PubMed

    Degen, A A

    1998-01-01

    Feeding and the search for food are the predominant activities of most rodents. Since desert rodents inhabit regions of generally low food availability, it has been theorized that their energetic requirements would be lower and/or their efficiency to use energy for maintenance and growth would be higher than for rodents from more temperate regions. Indeed, the basal metabolic rate, average daily metabolic rate and field metabolic rate of desert rodents have been found to be lower than those of non-desert rodents. However, the ability to use energy intake for maintenance by desert rodents was calculated to be lower than that of non-desert rodents. In addition, granivores were not different from omnivores and herbivores in energy use efficiency, but herbivores were more efficient than omnivores.

  15. Namibia [South-West Africa].

    PubMed

    1983-01-01

    Namibia, a country of 1,051,700 inhabitants of whom 85.6% are blacks of diverse ethnic and linguistic origins, 7.5% are white, and the rest are of mixed ancestry, has been illegally administered by South Africa since 1966, when a League of Nations mandate was revoked by the UN. The Namibian Desert was a barrier to European expansion until the late 18th century, when the area came under German and British influence. Efforts to bring about an orderly and peaceful transition to independent status are hampered at present by the lack of parallel progress toward withdrawal of Cuban combat forces from Angola. Beginning in 1980, considerable executive power was transferred from the administrator general appointed by the South African Government to an interim 3-tier system of elected representatives dividing responsibility between central, ethnic, and local authorities. The judicial structure has separate overlapping systems for whites, westernized blacks and coloreds and for indigenous blacks. Namibian society is highly politicized, with 4 white and about 40 nonwhite political groups. The South West Africa People's Organization (SWAPO) remains an active party inside Namibia despite simultaneous detention of its entire leadership in 1979 by the South African Government. Namibia's economy is dual, with a modern market sector of mining, ranching and fishing producing most of the wealth and a traditional subsistence sector supporting most of the labor force. About 60% of the work force of 500,000 in 1981 worked in agriculture, 19% in industry and commerce, 6% in mining, 8% in services, and 7% in government. Namibia's gross domestic product in 1980 was $1.712 billion, representing an average growth rate of 2.5% from 1970-80. However, real growth since 1978 has been negative because of persistent drought, political uncertainty, low demand for mineral products, and previous overfishing. Namibia has no separate representation in any international body. The country may have the

  16. Rainbows in the Indian rock art of desert western America.

    PubMed

    Sassen, K

    1991-08-20

    For thousands of years the image of the rainbow was pecked and painted by native Americans onto the rocks of the Great Basin and the Southwest. This long-lived tradition, which transcended major developments in lifestyles and cultures, underscores the important symbolic significance of the rainbow to the inhabitants of this arid region. The rainbow rock art depictions were usually associated with humanlike ceremonial figures, snakes, clouds, rain, and lightning bolts, suggesting that the rainbow symbol was employed as part of an elaborate sacred tradition. Although such ceremonial usage of the rainbow image tends to lead to abstraction and symbolic representation, there are examples, including a properly colorized rainbow painting from central Utah (approximately a thousand years old), that indicate observationally based rainbow reproductions of relatively great antiquity.

  17. Rainbows in the Indian rock art of desert western America.

    PubMed

    Sassen, K

    1991-08-20

    For thousands of years the image of the rainbow was pecked and painted by native Americans onto the rocks of the Great Basin and the Southwest. This long-lived tradition, which transcended major developments in lifestyles and cultures, underscores the important symbolic significance of the rainbow to the inhabitants of this arid region. The rainbow rock art depictions were usually associated with humanlike ceremonial figures, snakes, clouds, rain, and lightning bolts, suggesting that the rainbow symbol was employed as part of an elaborate sacred tradition. Although such ceremonial usage of the rainbow image tends to lead to abstraction and symbolic representation, there are examples, including a properly colorized rainbow painting from central Utah (approximately a thousand years old), that indicate observationally based rainbow reproductions of relatively great antiquity. PMID:20706421

  18. Chihuahuan Deserts Ecoregion: Chapter 27 in Status and trends of land change in the Western United States--1973 to 2000

    USGS Publications Warehouse

    Ruhlman, Jana; Gass, Leila; Middleton, Barry

    2012-01-01

    The Chihuahuan Desert is the largest of the North American deserts, extending from southern New Mexico and Texas deep into Mexico, with approximately 90 percent of its area falling south of the United States–Mexico border (Lowe, 1964, p. 24). The Chihuahuan Deserts Ecoregion covers approximately 174,472 km2 (67,364 mi2) within the United States, including much of west Texas, southern New Mexico, and a small portion of southeastern Arizona (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The ecoregion is generally oriented from northwest to southeast, with the Madrean Archipelago Ecoregion to the west; the Arizona/New Mexico Mountains, Arizona/New Mexico Plateau, Southwestern Tablelands, and Western High Plains Ecoregions to the north; and the Edwards Plateau and Southern Texas Plains Ecoregions to the east (fig. 1).

  19. Widespread natural perchlorate in unsaturated zones of the southwest United States

    USGS Publications Warehouse

    Rao, B.; Anderson, T.A.; Orris, G.J.; Rainwater, K.A.; Rajagopalan, S.; Sandvig, R.M.; Scanlon, B.R.; Stonestrom, D.A.; Walvoord, M.A.; Jackson, W.A.

    2007-01-01

    A substantial reservoir (up to 1 kg ha-1) of natural perchlorate is present in diverse unsaturated zones of the arid and semi-arid southwestern United States. The perchlorate co-occurs with meteoric chloride that has accumulated in these soils throughout the Holocene [0 to 10-15 ka (thousand years ago)] and possibly longer periods. Previously, natural perchlorate widely believed to be limited to the Atacama Desert, now appears widespread in steppe-to-desert ecoregions. The perchlorate reservoir becomes sufficiently large to affect groundwater when recharge from irrigation or climate change flushes accumulated salts from the unsaturated zone. This new source may help explain increasing reports of perchlorate in dry region agricultural products and should be considered when evaluating overall source contributions. ?? 2007 American Chemical Society.

  20. On Separate Paths: The Mexican American and African American Legal Campaigns against School Segregation

    ERIC Educational Resources Information Center

    Powers, Jeanne M.

    2014-01-01

    "Brown v. Board of Education" (1954) was a landmark decision that was the result of decades of efforts by grassroots activists and civil rights organizations to end legalized segregation. A less well-known effort challenged the extralegal segregation of Mexican American students in the Southwest. I combine original research and research…

  1. Desert Amplification in a Warming Climate.

    PubMed

    Zhou, Liming

    2016-01-01

    Here I analyze the observed and projected surface temperature anomalies over land between 50°S-50°N for the period 1950-2099 by large-scale ecoregion and find strongest warming consistently and persistently seen over driest ecoregions such as the Sahara desert and the Arabian Peninsula during various 30-year periods, pointing to desert amplification in a warming climate. This amplification enhances linearly with the global mean greenhouse gases(GHGs) radiative forcing and is attributable primarily to a stronger GHGs-enhanced downward longwave radiation forcing reaching the surface over drier ecoregions as a consequence of a warmer and thus moister atmosphere in response to increasing GHGs. These results indicate that desert amplification may represent a fundamental pattern of global warming associated with water vapor feedbacks over land in low- and mid- latitudes where surface warming rates depend inversely on ecosystem dryness. It is likely that desert amplification might involve two types of water vapor feedbacks that maximize respectively in the tropical upper troposphere and near the surface over deserts, with both being very dry and thus extremely sensitive to changes of water vapor. PMID:27538725

  2. Desert Amplification in a Warming Climate.

    PubMed

    Zhou, Liming

    2016-08-19

    Here I analyze the observed and projected surface temperature anomalies over land between 50°S-50°N for the period 1950-2099 by large-scale ecoregion and find strongest warming consistently and persistently seen over driest ecoregions such as the Sahara desert and the Arabian Peninsula during various 30-year periods, pointing to desert amplification in a warming climate. This amplification enhances linearly with the global mean greenhouse gases(GHGs) radiative forcing and is attributable primarily to a stronger GHGs-enhanced downward longwave radiation forcing reaching the surface over drier ecoregions as a consequence of a warmer and thus moister atmosphere in response to increasing GHGs. These results indicate that desert amplification may represent a fundamental pattern of global warming associated with water vapor feedbacks over land in low- and mid- latitudes where surface warming rates depend inversely on ecosystem dryness. It is likely that desert amplification might involve two types of water vapor feedbacks that maximize respectively in the tropical upper troposphere and near the surface over deserts, with both being very dry and thus extremely sensitive to changes of water vapor.

  3. Desert Amplification in a Warming Climate

    PubMed Central

    Zhou, Liming

    2016-01-01

    Here I analyze the observed and projected surface temperature anomalies over land between 50°S-50°N for the period 1950–2099 by large-scale ecoregion and find strongest warming consistently and persistently seen over driest ecoregions such as the Sahara desert and the Arabian Peninsula during various 30-year periods, pointing to desert amplification in a warming climate. This amplification enhances linearly with the global mean greenhouse gases(GHGs) radiative forcing and is attributable primarily to a stronger GHGs-enhanced downward longwave radiation forcing reaching the surface over drier ecoregions as a consequence of a warmer and thus moister atmosphere in response to increasing GHGs. These results indicate that desert amplification may represent a fundamental pattern of global warming associated with water vapor feedbacks over land in low- and mid- latitudes where surface warming rates depend inversely on ecosystem dryness. It is likely that desert amplification might involve two types of water vapor feedbacks that maximize respectively in the tropical upper troposphere and near the surface over deserts, with both being very dry and thus extremely sensitive to changes of water vapor. PMID:27538725

  4. Desert Amplification in a Warming Climate

    NASA Astrophysics Data System (ADS)

    Zhou, Liming

    2016-08-01

    Here I analyze the observed and projected surface temperature anomalies over land between 50°S-50°N for the period 1950–2099 by large-scale ecoregion and find strongest warming consistently and persistently seen over driest ecoregions such as the Sahara desert and the Arabian Peninsula during various 30-year periods, pointing to desert amplification in a warming climate. This amplification enhances linearly with the global mean greenhouse gases(GHGs) radiative forcing and is attributable primarily to a stronger GHGs-enhanced downward longwave radiation forcing reaching the surface over drier ecoregions as a consequence of a warmer and thus moister atmosphere in response to increasing GHGs. These results indicate that desert amplification may represent a fundamental pattern of global warming associated with water vapor feedbacks over land in low- and mid- latitudes where surface warming rates depend inversely on ecosystem dryness. It is likely that desert amplification might involve two types of water vapor feedbacks that maximize respectively in the tropical upper troposphere and near the surface over deserts, with both being very dry and thus extremely sensitive to changes of water vapor.

  5. Background-like nitrate in desert air

    NASA Astrophysics Data System (ADS)

    Wu, Feng; Zhang, Daizhou; Cao, Junji; Zhang, Ting; An, Zhisheng

    2014-02-01

    The atmospheric nitrogen cycle is a key process driving the earth's environmental evolution. Current model studies require knowledge of NOx soil emissions from various land types, but desert emissions remain unquantified or are not addressed with high confidence. Our measurements at two observatories in Taklimakan desert during a dust episode showed an approximately stable and dust-independent nitrate in the air. Its concentration estimated from PM2.5, PM10 and TSP samples under non-dust, floating dust and dust storm conditions was 3.81 ± 1.24 μg m-3, 2.95 ± 0.69 μg m-3, 4.99 ± 1.71 μg m-3, respectively, despite the more-than-one-order difference of dust loading. This concentration was much larger than that in remote marine and tropical forest air. Comprehensive investigation revealed a similar presence of nitrate in other desert air. The nitrate was hypothesized to be the consequence of the conversion of NOx released from desert soils. These results indicate a background-like nitrate and active reactions of nitrogen compounds in desert air.

  6. Assessing Climate Change Impacts for Military Installations in the Southwest United States During the Warm Season

    NASA Astrophysics Data System (ADS)

    Castro, C.

    2013-05-01

    Arid and semi-arid regions are experiencing some of the most adverse impacts of climate change with increased heat waves, droughts, and extreme weather. These events will likely exacerbate socioeconomic and political instabilities in regions where the United States has vital strategic interests and ongoing military operations. The Southwest U.S. is strategically important in that it houses some of the most spatially expansive and important military installations in the country. The majority of severe weather events in the Southwest occur in association with the North American monsoon system (NAMS), and current observational record has shown a 'wet gets wetter and dry gets drier' global monsoon precipitation trend. We seek to evaluate the warm season extreme weather projection in the Southwest U.S., and how the extremes can affect Department of Defense (DoD) military facilities in that region. A baseline methodology is being developed to select extreme warm season weather events based on historical sounding data and moisture surge observations from Gulf of California. Numerical Weather Prediction (NWP)-type high resolution simulations will be performed for the extreme events identified from Weather Research and Forecast (WRF) model simulations initiated from IPCC GCM and NCAR Reanalysis data in both climate control and climate change periods. The magnitude in extreme event changes will be analyzed, and the synoptic forcing patterns of the future severe thunderstorms will provide a guide line to assess if the military installations in the Southwest will become more or less susceptible to severe weather in the future.

  7. SOUTHWEST REGIONAL PARTNERSHIP ON CARBON SEQUESTRATION

    SciTech Connect

    Brian McPherson; Rick Allis; Barry Biediger; Joel Brown; Jim Cappa; George Guthrie; Richard Hughes; Eugene Kim; Robert Lee; Dennis Leppin; Charles Mankin; Orman Paananen; Rajesh Pawar; Tarla Peterson; Steve Rauzi; Jerry Stuth; Genevieve Young

    2004-11-01

    The Southwest Partnership Region includes six whole states, including Arizona, Colorado, Kansas, New Mexico, Oklahoma, and Utah, roughly one-third of Texas, and significant portions of adjacent states. The Partnership comprises a large, diverse group of expert organizations and individuals specializing in carbon sequestration science and engineering, as well as public policy and outreach. The main objective of the Southwest Partnership project is to achieve an 18% reduction in carbon intensity by 2012. The Partnership made great progress in this first year. Action plans for possible Phase II carbon sequestration pilot tests in the region are almost finished, including both technical and non-technical aspects necessary for developing and carrying out these pilot tests. All partners in the Partnership are taking an active role in evaluating and ranking optimum sites and technologies for capture and storage of CO{sub 2} in the Southwest Region. We are identifying potential gaps in all aspects of potential sequestration deployment issues.

  8. The heat is on: desert tortoises and survival

    USGS Publications Warehouse

    Wessells, Stephen M.; Schwarzbach, Steven E.

    2010-01-01

    To highlight USGS scientists' research and build support for the work being done to help with desert tortoise recovery. To educate people about desert tortoises, their habitat needs, and what people might do to help. Length: 30 minutes

  9. Water relations of riparian plants from warm desert regions

    USGS Publications Warehouse

    Smith, S.D.; Devitt, Dale A.; Cleverly, James R.; Busch, David E.

    1998-01-01

    Riparian plants have been classified as 'drought avoiders' due to their access to an abundant subsurface water supply. Recent water-relations research that tracks water sources of riparian plants using the stable isotopes of water suggests that many plants of the riparian zone use ground water rather than stream water, and not all riparian plants are obligate phreatophytes (dependent on ground water as a moisture source) but may occasionally be dependent of unsaturated soil moisture sources. A more thorough understanding of riparian plant-water relations must include water-source dynamics and how those dynamics vary over both space and time. Many rivers in the desert Southwest have been invaded by the exotic shrub Tamarix ramosissima (saltcedar). Our studies of Tamarix invasion into habitats formerly dominated by native riparian forests of primarily Populus and Salix have shown that Tamarix successfully invades these habitats because of its (1) greater tolerance to water stress and salinity, (2) status as a facultative, rather than obligate, phreatophyte and, therefore, its ability to recover from droughts and periods of ground-water drawdown, and (3) superior regrowth after fire. Analysis of water- loss rates indicate that Tamarix-dominated stands can have extremely high evapotranspiration rates when water tables are high but not necessarily when water tables are lower. Tamarix has leaf-level transpiration rates that are comparable to native species, whereas sap-flow rates per unit sapwood area are higher than in natives, suggesting that Tamarix maintains higher leaf area than can natives, probably due to its greater water stress tolerance. Tamarix desiccates and salinizes floodplains, due to its salt exudation and high transpiration rates, and may also accelerate fire cycles, thus predisposing these ecosystems to further loss of native taxa. Riparian species on regulated rivers can be exposed to seasonal water stress due to depression of floodplain water tables

  10. Desert pavements and associated rock varnish in the Mojave Desert: How old can they be?

    NASA Astrophysics Data System (ADS)

    Quade, Jay

    2001-09-01

    Desert pavements are common features of arid landscapes and have been widely used as a relative age indicator of the geomorphic surfaces upon which they are developed. In this study I examined the patterns of pavement development as a function of elevation in the Mojave Desert as well as the causes for the gradual disappearance of pavement at high elevations. Pavement density, as measured by percentage of pebble coverage, decreases systematically with elevation gain by ˜3% per 100 m, from 95% coverage below 500 m to less than 60% at 1700 m. Plants appear to be the main agent of pavement disruption; plant density decreases as pavement density increases. Burrowing by rodents and crusting by cryptobiota also disrupt pavement development at higher elevation. During the last glacial maximum, plant communities were displaced 1000 1400 m downward in the Mojave Desert. Pavements today generally do not survive above the blackbush (Coleogyne ramossisma)-sagebrush (Artemisia tridentata) zone. Evidence from packrat middens shows that these and other plants typical of high elevations today grew as low as 300 400 m during the last glacial maximum. I suggest that during the last glacial maximum, desert pavements were confined to the lowest alluvial fans of Death Valley and adjoining low valleys. No alluvial desert pavements above ˜400 m in the region are older than the latest Pleistocene. By the same reasoning, desert varnish on desert pavements above 400 m may all be Holocene in age, except where developed on stable boulders.

  11. SOUTHWEST REGIONAL PARTNERSHIP ON CARBON SEQUESTRATION

    SciTech Connect

    Brian McPherson

    2005-08-01

    The Southwest Partnership on Carbon Sequestration completed several more tasks during the period of October 1, 2004--March 31, 2005. The main objective of the Southwest Partnership project is to achieve an 18% reduction in carbon intensity by 2012. Action plans for possible Phase 2 carbon sequestration pilot tests in the region are completed, and a proposal was developed and submitted describing how the Partnership may develop and carry out appropriate pilot tests. The content of this report focuses on Phase 1 objectives completed during this reporting period.

  12. [Response of morphological characteristics of Populus euphratica nebkhas to groundwater in Birkum Desert, west of Taklimakan].

    PubMed

    Zhang, Zhan-he; Lai, Feng-bing; Chen, Shu-jiang

    2015-09-01

    By regarding the east of Birkum desert of the west of Taklimakan as research areas, the paper measured the basic morphological characteristics of Populus euphratica nebkhas through real-time kinematics, got the relevant data of groundwater by manual drilling, and analyzed the response of emorphological characteristics of P. euphratica nebkhas to groundwater. The results showed that the change range of morphological parameters of P. euphratica nebkhas was large. Groundwater infil- trated the research areas from west, south and southwest to northwest and the depth of groundwater ranged from 0.15 m to 83.2 m. Except for the maximums of the length and circumference, the other morphological parameters of P. euphratica nebkhas had a negative relation with the depth of groundwater. The volume of P. euphratica nebkhas was mainly in the range of 63.54-91.24 m3.

  13. Water-table fluctuations in the Amargosa Desert, Nye County, Nevada

    SciTech Connect

    Paces, James B.; Whelan, Joseph

    2001-04-29

    Pleistocene ground-water discharge deposits approximately 20 km southwest of Yucca Mountain were previously thought to represent pluvial water-table rises of 80 to 120 m. Data from new boreholes at two of the three discharge sites indicate that the modern water-table is at depths of only 17 to 30 m and that this shallow water is part of the regional ground-water flow system rather than being perched. Calcite in equilibrium with this modern ground water would have isotopic compositions similar to those in Pleistocene calcite associated with the discharge deposits. Carbon and uranium isotopes in both ground water and discharge deposits imply that past discharge consisted of a mixture of both shallow and deep ground water. These data limit Pleistocene water-table fluctuations at the specified Amargosa Desert discharge sites to between 17 and 30 m and eliminate the need to invoke large water-table rises.

  14. Establishing food site vectors in desert ants.

    PubMed

    Bolek, Siegfried; Wittlinger, Matthias; Wolf, Harald

    2012-02-15

    When returning to the site of a successful previous forage, where does one search for the goodies? Should one rely on experience from the previous homebound journey, or should one consider the outbound journey as well, or even exclusively? Desert ants are particularly well suited for pursuing this question because of their primary reliance on path integration in open and featureless desert habitats. Path integration has been studied particularly with regard to homing after lengthy foraging trips. The ants also use path integration to return to plentiful feeding sites, but what is memorised for revisiting the feeder remains controversial. Here, we demonstrate that desert ants consider, and indeed linearly average, both outbound and inbound travel for their return to a familiar feeder. This may be interpreted as a strategy to reduce navigation errors.

  15. New lakes in the Taklamakan Desert

    NASA Astrophysics Data System (ADS)

    Chen, Jiansheng; Wang, Chi-Yuen; Tan, Hongbing; Rao, Wenbo; Liu, Xiaoyan; Sun, Xiaoxu

    2012-11-01

    At the beginning of this century, some new lakes unexpectedly appeared in the Taklamakan Desert - one of the largest and driest deserts in the world. The origin of the water in the new lakes, however, has been a matter of debate. We test the hypotheses by analyzing water samples collected from the new lakes, the Bosten Lake and the foothills of the mountains that surround the desert. Using the isotopic composition of these waters as tracers, together with data from remote sensing, local weather stations and stream gauges, we infer that the new lakes may originate from increased recharge of groundwater from meltwater in the nearby mountains. We further speculate, supported by first-order simulation of earthquake-induced discharge of groundwater from mountains, that the source of this increased recharge may be related to earthquake-induced discharge of groundwater from nearby Altyn and Kunlun Mountains.

  16. Pliocene climate change of the Southwest Pacific and the impact of ocean gateways

    NASA Astrophysics Data System (ADS)

    Karas, Cyrus; Nürnberg, Dirk; Tiedemann, Ralf; Garbe-Schönberg, Dieter

    2011-01-01

    The transition from the early Pliocene “Warmhouse” towards the present “Icehouse” climate and the role of Gateway dynamics are intensively debated. Both, the constrictions of the Central American Seaway and the Indonesian Gateway affected ocean circulation and climate during the Pliocene epoch. Here, we use combined δ18O and Mg/Ca ratios of planktonic foraminifera (marine protozoa) from surface and subsurface levels to reconstruct the thermal structure and changes in salinities from the Southwest Pacific Deep Sea Drilling Project (DSDP) Site 590B from 6.5 to 2.5 Ma. Our data suggest a gradual cooling of ~ 2 °C and freshening of the sea surface during ~ 4.6-4 Ma with an increased meridional temperature gradient between the West Pacific Warm Pool and the Southwest Pacific when the closing of the Central American Seaway reached a critical threshold. After ~ 3.5 Ma, the restricted Indonesian Gateway might have amplified the East Australian Current, allowing enhanced heat transport towards the Southwest Pacific with reduced meridional temperature gradients when the global climate gradually cooled. At the same time our data suggest a cooling and freshening of Subantarctic Mode Water (SAMW) or/and an increased northward flow of SAMW towards Site 590B, possibly a first step towards the present Antarctic Frontal System.

  17. Oxalosis in wild desert tortoises, Gopherus agassizii

    USGS Publications Warehouse

    Jacobson, Elliott R.; Berry, Kristin H.; Stacy, Brian; Huzella, Louis M.; Kalasinsky, Victor F.; Fleetwood, Michelle L.; Mense, Mark G.

    2009-01-01

    We necropsied a moribund, wild adult male desert tortoise (Gopherus agassizii) with clinical signs of respiratory disease and elevated plasma biochemical analytes indicative of renal disease (blood urea nitrogen [415 mg/dl], uric acid [11.8 mg/dl], sodium >180 mmol/l] and chloride [139 mmol/l]). Moderate numbers of birefringent oxalate crystals, based on infrared and electron microscopy, were present within renal tubules; small numbers were seen in colloid within thyroid follicles. A retrospective analysis of 66 additional cases of wild desert tortoises was conducted to determine whether similar crystals were present in thyroid and kidney. The tortoises, from the Mojave and Sonoran deserts, were necropsied between 1992 and 2003 and included juveniles and adults. Tortoises were classified as healthy (those that died due to trauma and where no disease was identified after necropsy and evaluation by standard laboratory tests used for other tortoises) or not healthy (having one or more diseases or lesions). For all 67 necropsied tortoises, small numbers of crystals of similar appearance were present in thyroid glands from 44 of 54 cases (81%) and in kidneys from three of 65 cases (5%). Presence of oxalates did not differ significantly between healthy and unhealthy tortoises, between age classes, or between desert region, and their presence was considered an incidental finding. Small numbers of oxalate crystals seen within the kidney of two additional tortoises also were considered an incidental finding. Although the source of the calcium oxalate could not be determined, desert tortoises are herbivores, and a plant origin seems most likely. Studies are needed to evaluate the oxalate content of plants consumed by desert tortoises, and particularly those in the area where the tortoise in renal failure was found.

  18. The Punitive Paradox: Desert and the Compulsion to Punish.

    ERIC Educational Resources Information Center

    Clear, Todd R.

    1996-01-01

    Explores the concept of a "just deserts" justice paradox in which carrying out a deserved penalty breaches the values that undergird the theory of just deserts. Examines whether it might ever be proper, from a desert perspective, to choose not to impose a deserved punishment. (KW)

  19. An Economic View of Food Deserts in the United States

    ERIC Educational Resources Information Center

    Bitler, Marianne; Haider, Steven J.

    2011-01-01

    Considerable policy and academic attention has been focused on the topic of food deserts. We consider this topic from an economic perspective. First, we consider how the components of a standard economic analysis apply to the study of food deserts. Second, using this economic lens, we revisit the empirical literature on food deserts to assess the…

  20. 75 FR 19246 - Safety Zone; Desert Storm, Lake Havasu, AZ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-14

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Desert Storm, Lake Havasu, AZ AGENCY: Coast... Havasu City, Arizona in support of the Desert Storm Exhibition Run. This temporary safety zone is... Purpose The Lake Racer LLC is sponsoring the Desert Storm Charity Poker Run and Exhibition Run, which...

  1. 13. Southwest corner of burning hood and incinerator. North wall ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Southwest corner of burning hood and incinerator. North wall of scrubber cell room. Looking southwest. - Plutonium Finishing Plant, Waste Incinerator Facility, 200 West Area, Richland, Benton County, WA

  2. 1. Keeper's house and light tower, view north northeast, southwest ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Keeper's house and light tower, view north northeast, southwest and southeast sides of house, northwest and southwest sides of tower - Wood Island Light Station, East end of Wood Island, at mouth of Soo River, Biddeford Pool, York County, ME

  3. 1. THE CHANGE HOUSE (OR 'DRY') LOOKING TO THE SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. THE CHANGE HOUSE (OR 'DRY') LOOKING TO THE SOUTHWEST (STONE ELECTRIC POWER STATION IS IN THE BACKGROUND). - Foster Gulch Mine, Change House, Bear Creek 1 mile Southwest of Town of Bear Creek, Red Lodge, Carbon County, MT

  4. 4. BUILDING 422, WEST SIDE, FROM APPROXIMATELY 25 FEET SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. BUILDING 422, WEST SIDE, FROM APPROXIMATELY 25 FEET SOUTHWEST OF SOUTHWEST CORNER, LOOKING NORTHEAST. - Oakland Naval Supply Center, Aeronautical Materials Storehouses, Between E & G Streets, between Fourth & Sixth Streets, Oakland, Alameda County, CA

  5. View from southwest to northeast of industrial building. Far right ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View from southwest to northeast of industrial building. Far right doors lead to vehicle service and maintenance bays - Stanley R. Mickelsen Safeguard Complex, Industrial Building, One block southwest of Limited Area Sentry Station, Nekoma, Cavalier County, ND

  6. View of automotive repair and gas station, facing southwest from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of automotive repair and gas station, facing southwest from across Pope Street. Garage built for storage of employee automobiles in left background - Automotive Repair & Gas Station, Southwest corner of Pope Street & Olympic Avenue, Port Gamble, Kitsap County, WA

  7. 3. VIEW TO SOUTHWEST (NORTHEAST CORNER OF EDIBLE FATS FACTORY) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. VIEW TO SOUTHWEST (NORTHEAST CORNER OF EDIBLE FATS FACTORY) - Wilson's Oil House, Lard Refinery, & Edible Fats Factory, Edible Fats Factory, 2801 Southwest Fifteenth Street, Oklahoma City, Oklahoma County, OK

  8. 23. Third floor, third level of milk room, looking southwest ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Third floor, third level of milk room, looking southwest at existing dairy equipment (original location of pasteurizing holding cylinders) - Sheffield Farms Milk Plant, 1075 Webster Avenue (southwest corner of 166th Street), Bronx, Bronx County, NY

  9. 78 FR 78810 - Pacific Southwest Recreation Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    ...; ] DEPARTMENT OF AGRICULTURE Forest Service Pacific Southwest Recreation Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Pacific Southwest Recreation Resource Advisory Committee (Recreation RAC) will meet in San Bernardino, California. The Recreation RAC...

  10. 78 FR 49253 - Pacific Southwest Recreation Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-13

    ... Forest Service Pacific Southwest Recreation Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Pacific Southwest Recreation Resource Advisory Committe will meet in Sacramento, California. The Committee is authorized under the Federal Lands Recreation...

  11. 2. MORAVIAN POTTERY AND TILE WORKS, VIEW FROM THE SOUTHWEST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. MORAVIAN POTTERY AND TILE WORKS, VIEW FROM THE SOUTHWEST. INDIAN HOUSE WING AT THE LEFT. - Moravian Pottery & Tile Works, Southwest side of State Route 313 (Swamp Road), Northwest of East Court Street, Doylestown, Bucks County, PA

  12. 48. Second floor, looking southwest (possibly former multipurpose room) with ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    48. Second floor, looking southwest (possibly former multi-purpose room) with fire stair in center - Sheffield Farms Milk Plant, 1075 Webster Avenue (southwest corner of 166th Street), Bronx, Bronx County, NY

  13. 1. EXTERIOR VIEW SHOWING THE SOUTHWEST & SOUTHEAST SIDES OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. EXTERIOR VIEW SHOWING THE SOUTHWEST & SOUTHEAST SIDES OF THE AUDITORIUM, LOOKING NORTHEAST - Fort McCoy, Building No. T-1056, Southwest of intersection of South Tenth Avenue & South "X" Street, Block 10, Sparta, Monroe County, WI

  14. Interior general view of stair well at southwest corner showing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior general view of stair well at southwest corner showing stair enclosure and typical steel fire door; view to southwest. - Lawrence Machine Shop, Building No. 4, 70 General Street, Lawrence, Essex County, MA

  15. GARAGE (L) IN RELATION TO TENANT HOUSE (R), LOOKING SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GARAGE (L) IN RELATION TO TENANT HOUSE (R), LOOKING SOUTHWEST - Irvine Ranch Agricultural Headquarters, Carillo Tenant House, Southwest of Intersection of San Diego & Santa Ana Freeways, Irvine, Orange County, CA

  16. Trestle #1, southwest abutment and wing wall. View to west ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Trestle #1, southwest abutment and wing wall. View to west - Promontory Route Railroad Trestles, S.P. Trestle 779.91, One mile southwest of junction of State Highway 83 and Blue Creek, Corinne, Box Elder County, UT

  17. 2. NORTHEAST VIEW OF SOUTH SIDE WITH ADDITION ON SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. NORTHEAST VIEW OF SOUTH SIDE WITH ADDITION ON SOUTHWEST - Juniata Mill Complex, Mine & Camp Residence, 22.5 miles Southwest of Hawthorne, between Aurora Crater & Aurora Peak, Hawthorne, Mineral County, NV

  18. 3. EAST VIEW OF NORTHWEST AND SOUTHWEST SIDES OF BUILDING. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. EAST VIEW OF NORTHWEST AND SOUTHWEST SIDES OF BUILDING. COLLAPSED STRUCTURE IN FOREGROUND - Juniata Mill Complex, Mine Camp Building, 22.5 miles Southwest of Hawthorne, between Aurora Crater & Aurora Peak, Hawthorne, Mineral County, NV

  19. 2. NORTHEAST VIEW OF SOUTHWEST CORNER, WEST AND SOUTH SIDES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. NORTHEAST VIEW OF SOUTHWEST CORNER, WEST AND SOUTH SIDES - Juniata Mill Complex, Mine & Camp Residence, 22.5 miles Southwest of Hawthorne, between Aurora Crater & Aurora Peak, Hawthorne, Mineral County, NV

  20. 2. NORTHEAST VIEW OF SOUTHWEST CORNER, WEST AND SOUTH SIDES. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. NORTHEAST VIEW OF SOUTHWEST CORNER, WEST AND SOUTH SIDES. PARTIALLY SUNKEN TUB ON LEFT SIDE. - Juniata Mill Complex, Pump House, 22.5 miles Southwest of Hawthorne, between Aurora Crater & Aurora Peak, Hawthorne, Mineral County, NV

  1. 3. NORTHEAST VIEW OF SOUTHWEST CORNER (WEST AND SOUTH SIDES) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. NORTHEAST VIEW OF SOUTHWEST CORNER (WEST AND SOUTH SIDES) - Juniata Mill Complex, Camp Bunk House, 22.5 miles Southwest of Hawthorne, between Aurora Crater & Aurora Peak, Hawthorne, Mineral County, NV

  2. 1. VIEW NORTHNORTHWEST OF SOUTHEAST AND SOUTHWEST SIDES Juniata ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. VIEW NORTH-NORTHWEST OF SOUTHEAST AND SOUTHWEST SIDES - Juniata Mill Complex, Mine Camp Building, 22.5 miles Southwest of Hawthorne, between Aurora Crater & Aurora Peak, Hawthorne, Mineral County, NV

  3. A Reservoir of Nitrate Beneath Desert Soils

    USGS Publications Warehouse

    Walvoord, M.A.; Phillips, F.M.; Stonestrom, D.A.; Evans, R.D.; Hartsough, P.C.; Newman, B.D.; Striegl, R.G.

    2003-01-01

    A large reservoir of bioavailable nitrogen (upto ???104 kilograms of nitrogen per hectare, as nitrate) has been previously overlooked in studies of global nitrogen distribution. The reservoir has been accumulating in subsoil zones of and regions throughout the Holocene. Consideration of the subsoil reservoir raises estimates of vadose-zone nitrogen inventories by 14 to 71% for warm deserts and arid shrublands worldwide and by 3 to 16% globally. Subsoil nitrate accumulation indicates long-term leaching from desert soils, impelling further evaluation of nutrient dynamics in xeric ecosystems. Evidence that subsoil accumulations are readily mobilized raises concern about groundwater contamination after land-use or climate change.

  4. Desert Dust Properties, Modelling, and Monitoring

    NASA Technical Reports Server (NTRS)

    Kaskaoutis, Dimitris G.; Kahn, Ralph A.; Gupta, Pawan; Jayaraman, Achuthan; Bartzokas, Aristides

    2013-01-01

    This paper is just the three-page introduction to a Special Issue of Advances in Meteorology focusing on desert dust. It provides a paragraph each on 13 accepted papers, most relating to the used of satellite data to assess attributes or distribution of airborne desert dust. As guest Associate Editors of this issue, we organized the papers into a systematic whole, beginning with large-scale transport and seasonal behavior, then to regional dust transport, transport history, and climate impacts, first in the Mediterranean region, then India and central Asia, and finally focusing on transport model assessment and the use of lidar as a technique to constrain dust spatial-temporal distribution.

  5. A reservoir of nitrate beneath desert soils.

    PubMed

    Walvoord, Michelle A; Phillips, Fred M; Stonestrom, David A; Evans, R Dave; Hartsough, Peter C; Newman, Brent D; Striegl, Robert G

    2003-11-01

    A large reservoir of bioavailable nitrogen (up to approximately 10(4) kilograms of nitrogen per hectare, as nitrate) has been previously overlooked in studies of global nitrogen distribution. The reservoir has been accumulating in subsoil zones of arid regions throughout the Holocene. Consideration of the subsoil reservoir raises estimates of vadose-zone nitrogen inventories by 14 to 71% for warm deserts and arid shrublands worldwide and by 3 to 16% globally. Subsoil nitrate accumulation indicates long-term leaching from desert soils, impelling further evaluation of nutrient dynamics in xeric ecosystems. Evidence that subsoil accumulations are readily mobilized raises concern about groundwater contamination after land-use or climate change.

  6. Predatory bird populations in the east Mojave Desert, California

    USGS Publications Warehouse

    Knight, R.L.; Camp, R.J.; Boarman, W.I.; Knight, H.A.L.

    1999-01-01

    We surveyed 7 species of predatory birds weekly during a 12-month period (December 1992 through November 1993) in the east Mojave Desert, California. The Common Raven (Corvus corax) was the most frequently observed species with an average of 6.9 sightings per 100 km. Turkey Vultures (Cathartes aura), Red-tailed Hawks (Buteo jamaicensis), Loggerhead Shrikes (Lanius ludovicianus), American Kestrels (Falco sparverius), Golden Eagles (Aquila chrysaetos), and Prairie Falcons (Falco mexicanus) were seen in decreasing order of frequency of observation through the study period. Ravens, Red-tailed Hawks, Loggerhead Shrikes, American Kestrels, and Prairie Falcons were seen throughout the year. Turkey Vultures were not present during winter months, while Golden Eagles were seen only during November and December. Turkey Vultures, Red-tailed Hawks, and ravens were most numerous on agricultural lands, while Loggerhead Shrikes were most Common at urban areas. Raven numbers increased with increasing number of linear rights-of-way parallel to the survey route. Perching was the most common behavior type, although Turkey Vultures and ravens were often observed soaring, flying, or standing on the ground near highways. Transmission powerline towers and telephone poles were used as perch sites disproportionately to availability.

  7. Geochemical registers of Late Quaternary paleoclimatic conditions at Sonora and Chihuahua Deserts, Mexico: comparison and synthesis

    NASA Astrophysics Data System (ADS)

    Roy, P.; Perez-Cruz, L. L.; Lozano-Garcia, S.

    2011-12-01

    Sonora and Chihuahua Deserts form the southwestern and southeastern parts of North American Desert system and spread over at least 5 different states in the northern Mexico. Presently, Sonora Desert receives annual precipitation in a bi-modal distribution, whereas Chihuahua Desert receives dominant summer precipitation. Paleoclimatic registers from Mojave Desert suggest that the spatial extent and magnitude of both the summer and winter precipitation varied during the last glacial period and such fluctuations were linked to the volume of the Laurentide ice sheet, changing winter-summer insolation, North Atlantic climatic variability and ENSO dynamics. We present multi-elemental concentrations, magnetic susceptibility, organic and inorganic carbon from 750 cm long sediment core collected from paleolake San Felipe (31°N, western Sonora Desert) and 970 cm long sediment core collected from paleolake Babicora (29°N, western Chihuahua Desert) in order to understand the paleohydrological and paleoclimatic evolution in the arid region of northern Mexico. 6 AMS 14C dates constrain the San Felipe sediment core between 49 cal kyr BP and present. Similarly, 8 AMS 14C dates put the Babicora core in the age bracket between 76 cal kyr BP and present with two different hiatus at 4-8 cal kyr BP and 40-45 cal kyr BP. Due to the special geomorphology of San Felipe basin, Ti concentration was used as a proxy for pluvial discharge and to differentiate regimes of dominant summer and winter precipitation. Aeolian deposition was constrained at >48 cal kyr BP. Period of lower pluvial discharge during 14-48 cal kyr BP is related to a regime of dominant winter frontal storms. During 3-14 cal kyr BP, higher catchment erosion and transportation of REE bearing heavy minerals into the basin are possibly as a result of higher pluvial discharge related to a regime of dominant summer precipitation. In paleolake Babicora, high resolution Ti suggests higher pluvial inflow prior to 60 cal kyr BP (H

  8. EPA's Southwest Ecosystem Services Research Program

    EPA Science Inventory

    EPA's Ecosystem Services Research Program (ESRP) in the Office of Research and Development (ORD) is studying ecosystem services and the benefits to human well-being provided by ecological services. As part of this research effort, the Southwest Ecosystem Services Research Progra...

  9. Investigating Ecosystems Services in the Arid Southwest

    EPA Science Inventory

    The Southwest Ecosystem Services Project (SwESP) is an integrated, multi-disciplinary, multi-agency project focused on how to identify, characterize, and quantify the ecosystem services in the southwestern United States and northern Mexico. The southwestern landscape is highly d...

  10. Southwest Energy Innovation Forum: Summary Report

    ERIC Educational Resources Information Center

    Ewing Marion Kauffman Foundation, 2010

    2010-01-01

    The Ewing Marion Kauffman Foundation, Arizona State University (ASU), and U.S. Department of Energy's Advanced Research Projects Agency-Energy (ARPA-E) co-convened a conference on Energy Innovation in the Southwest region of the United States that included participation by entrepreneurs, state government officials, representatives of academia,…

  11. USDA Southwest climate hub for climate change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA Southwest (SW) Climate Hub was created in February 2014 to develop risk adaptation and mitigation strategies for coping with climate change effects on agricultural productivity. There are seven regional hubs across the country with three subsidiary hubs. The SW Climate Hub Region is made up...

  12. Sedimentary Rocks and Methane - Southwest Arabia Terra

    NASA Technical Reports Server (NTRS)

    Allen, Carlton C.; Oehler, Dorothy Z.; Venechuk, Elizabeth M.

    2006-01-01

    We propose to land the Mars Science Laboratory in southwest Arabia Terra to study two key aspects of martian history the extensive record of sedimentary rocks and the continuing release of methane. The results of this exploration will directly address the MSL Scientific Objectives regarding biological potential, geology and geochemistry, and past habitability.

  13. Comparison of remote sensing indices for monitoring of desert cienegas

    USGS Publications Warehouse

    Wilson, Natalie R; Norman, Laura M.; Villarreal, Miguel; Gass, Leila; Tiller, Ron; Salywon, Andrew

    2016-01-01

    This research considers the applicability of different vegetation indices at 30 m resolution for mapping and monitoring desert wetland (cienega) health and spatial extent through time at Cienega Creek in southeastern Arizona, USA. Multiple stressors including the risk of decadal-scale drought, the effects of current and predicted global warming, and continued anthropogenic pressures threaten aquatic habitats in the southwest and cienegas are recognized as important sites for conservation and restoration efforts. However, cienegas present a challenge to satellite-imagery based analysis due to their small size and mixed surface cover of open water, exposed soils, and vegetation. We created time series of five well-known vegetation indices using annual Landsat Thematic Mapper (TM) images retrieved during the April–June dry season, from 1984 to 2011 to map landscape-level distribution of wetlands and monitor the temporal dynamics of individual sites. Indices included the Normalized Difference Vegetation Index (NDVI), the Soil-Adjusted Vegetation Index (SAVI), the Normalized Difference Water Index (NDWI), and the Normalized Difference Infrared Index (NDII). One topographic index, the Topographic Wetness Index (TWI), was analyzed to examine the utility of topography in mapping distribution of cienegas. Our results indicate that the NDII, calculated using Landsat TM band 5, outperforms the other indices at differentiating cienegas from riparian and upland sites, and was the best means to analyze change. As such, it offers a critical baseline for future studies that seek to extend the analysis of cienegas to other regions and time scales, and has broader applicability to the remote sensing of wetland features in arid landscapes.

  14. New Insights in Preservation of Meteorites in Hot Deserts: The Oldest Hot Desert Meteorite Collection.

    NASA Astrophysics Data System (ADS)

    Hutzler, A.; Rochette, P.; Bourlès, D.; Gattacceca, J.; Merchel, S.; Jull, A. J. T.; Valenzuela, M.

    2016-08-01

    Terrestrial ages of a subset of a chilean meteorite collection have been determined with cosmogenic nuclides. We show here that provided the environnement is favorable enough, hot desert meteorites can survive over a million year.

  15. Distribution, habitat and habits of the desert tortoise (Gopherus agassizii) in the eastern Mojave Desert

    SciTech Connect

    Esque, T.C.; Bury, R.B. ); Medica, P.A. )

    1990-01-01

    The desert tortoise is widely distributed across most of southern Nevada below 1500 meters elevation and then ranges northeast into the Arizona Strip and southwestern Utah. There are several large populations, but also many isolated groups of desert tortoises due to the rugged topography and, possibly, unsuitable soils. We suggest that the greatest threats to tortoises in the eastern Mojave Desert are with peripheral populations. Tortoises in the eastern Mojave Desert occupy a wide variety of habitats from flats and bajadas in lower elevation to rocky slopes bordering on blackbrush and juniper woodland. In winter they use shallow burrows near Las Vegas but frequent deep caves in the northeast edge of their range. Tortoises in all areas may occur in steep, rocky habitats. Climatic extremes are frequent in this region and rainfall can be spotty due to several major mountain ranges that cause rain shadows. Forage is highly variable and this species can be an opportunistic herbivore. 11 refs., 13 figs.

  16. USDA Southwest Regional Hub for Adaptation to and Mitigation of Climate Change

    NASA Astrophysics Data System (ADS)

    Rango, A.; Elias, E.; Steele, C. M.; Havstad, K.

    2014-12-01

    The USDA Southwest (SW) Climate Hub was created in February 2014 to develop risk adaptation and mitigation strategies for coping with climate change effects on agricultural productivity. There are seven regional hubs across the country with three subsidiary hubs. The SW Climate Hub Region is made up of six states: New Mexico, Arizona, Utah, Nevada, California and Hawaii (plus the Trust Territories of the Pacific Islands). The SW Climate Hub has a subsidiary hub located in Davis, California. The Southwest region has high climatic diversity, with the lowest and highest average annual rainfall in the U.S.(6.0 cm in Death Valley, CA and 1168 cm at Mt. Waialeale, HI). There are major deserts in five of the six states, yet most of the states, with exception of Hawaii, depend upon the melting of mountain snowpacks for their surface water supply. Additionally, many of the agricultural areas of the SW Regional Hub depend upon irrigation water to maintain productivity. Scientific climate information developed by the Hub will be used for climate-smart decision making. To do this, the SW Regional Hub will rely upon existing infrastructure of the Cooperative Extension Service at Land-Grant State Universities. Extension service and USDA-NRCS personnel have existing networks to communicate with stakeholders (farmers, ranchers, and forest landowners) through meetings and workshops which have already started in the six states. Outreach through the development of a weather and climate impact modules designed for seventh grade students and their teachers will foster education of future generations of rural land managers. We will be synthesizing and evaluating existing reports, literature and information on regional climate projections, water resources, and agricultural adaptation strategies related to climate in the Southwest. The results will be organized in a spatial format and provided through the SW Hub website (http://swclimatehub.info) and peer-reviewed articles.

  17. A mathematical model on the optimal timing of offspring desertion.

    PubMed

    Seno, Hiromi; Endo, Hiromi

    2007-06-01

    We consider the offspring desertion as the optimal strategy for the deserter parent, analyzing a mathematical model for its expected reproductive success. It is shown that the optimality of the offspring desertion significantly depends on the offsprings' birth timing in the mating season, and on the other ecological parameters characterizing the innate nature of considered animals. Especially, the desertion is less likely to occur for the offsprings born in the later period of mating season. It is also implied that the offspring desertion after a partially biparental care would be observable only with a specific condition.

  18. A mathematical model on the optimal timing of offspring desertion.

    PubMed

    Seno, Hiromi; Endo, Hiromi

    2007-06-01

    We consider the offspring desertion as the optimal strategy for the deserter parent, analyzing a mathematical model for its expected reproductive success. It is shown that the optimality of the offspring desertion significantly depends on the offsprings' birth timing in the mating season, and on the other ecological parameters characterizing the innate nature of considered animals. Especially, the desertion is less likely to occur for the offsprings born in the later period of mating season. It is also implied that the offspring desertion after a partially biparental care would be observable only with a specific condition. PMID:17328918

  19. Habitat selection by juvenile Mojave Desert tortoises

    USGS Publications Warehouse

    Todd, Brian D; Halstead, Brian J.; Chiquoine, Lindsay P.; Peaden, J. Mark; Buhlmann, Kurt A.; Tuberville, Tracey D.; Nafus, Melia G.

    2016-01-01

    Growing pressure to develop public lands for renewable energy production places several protected species at increased risk of habitat loss. One example is the Mojave desert tortoise (Gopherus agassizii), a species often at the center of conflicts over public land development. For this species and others on public lands, a better understanding of their habitat needs can help minimize negative impacts and facilitate protection or restoration of habitat. We used radio-telemetry to track 46 neonate and juvenile tortoises in the Eastern Mojave Desert, California, USA, to quantify habitat at tortoise locations and paired random points to assess habitat selection. Tortoise locations near burrows were more likely to be under canopy cover and had greater coverage of perennial plants (especially creosote [Larrea tridentata]), more coverage by washes, a greater number of small-mammal burrows, and fewer white bursage (Ambrosia dumosa) than random points. Active tortoise locations away from burrows were closer to washes and perennial plants than were random points. Our results can help planners locate juvenile tortoises and avoid impacts to habitat critical for this life stage. Additionally, our results provide targets for habitat protection and restoration and suggest that diverse and abundant small-mammal populations and the availability of creosote bush are vital for juvenile desert tortoises in the Eastern Mojave Desert.

  20. Extrafloral nectar fuels ant life in deserts

    PubMed Central

    Aranda-Rickert, Adriana; Diez, Patricia; Marazzi, Brigitte

    2014-01-01

    Interactions mediated by extrafloral nectary (EFN)-bearing plants that reward ants with a sweet liquid secretion are well documented in temperate and tropical habitats. However, their distribution and abundance in deserts are poorly known. In this study, we test the predictions that biotic interactions between EFN plants and ants are abundant and common also in arid communities and that EFNs are only functional when new vegetative and reproductive structures are developing. In a seasonal desert of northwestern Argentina, we surveyed the richness and phenology of EFN plants and their associated ants and examined the patterns in ant–plant interaction networks. We found that 25 ant species and 11 EFN-bearing plant species were linked together through 96 pairs of associations. Plants bearing EFNs were abundant, representing ca. 19 % of the species encountered in transects and 24 % of the plant cover. Most ant species sampled (ca. 77 %) fed on EF nectar. Interactions showed a marked seasonal pattern: EFN secretion was directly related to plant phenology and correlated with the time of highest ant ground activity. Our results reveal that EFN-mediated interactions are ecologically relevant components of deserts, and that EFN-bearing plants are crucial for the survival of desert ant communities. PMID:25381258