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  1. Rio Grande Wetbacks: Mexican Migrant Workers.

    ERIC Educational Resources Information Center

    Norquest, Carrol

    Farmers in the Lower Rio Grande Valley of Texas saw a rise of wetback labor in the 1930s and 40s. The wetback laborers were Mexicans who had crossed the Rio Grande and were in the United States illegally to work. Carrol Norquest, a farmer in the Lower Rio Grande Valley, employed wetbacks regularly. In this book, Mr. Norquest writes about the…

  2. Rio Grande rift: An overview

    NASA Astrophysics Data System (ADS)

    Olsen, Kenneth H.; Scott Baldridge, W.; Callender, Jonathan F.

    1987-11-01

    The Rio Grande rift of the southwestern United States is one of the world's principal continental rift systems. It extends as a series of asymmetrical grabens from central Colorado, through New Mexico, to Presidio, Texas, and Chihuahua, Mexico—a distance of more than 1000 km. Although the Rio Grande rift is closely related in timing and structural style to the contiguous Basin and Range extensional province, the two can be distinguished by a variety of geological and geophysical signatures. Rifts (both oceanic and continental) can be defined as elongate depressions overlying places where the entire lithosphere has ruptured in extension. The lithosphere of the Rio Grande rift conforms to this definition, in that: (1) the crust is moderately thinned—Moho depths range from about 45 km under the flanks to about 33 km beneath the rift axis. (2) anomalously low P n velocities (7.6-7.8 km s -1) beneath the rift and a long wavelength gravity low suggest that the asthenosphere is in contact with the base of the crust. The P-velocity is abnormally low (6.4-6.5 km s -1) in the lower half of the crust beneath the rift, suggesting high crustal temperatures. However, associated seismic and volcanologic data indicate the sub-rift lower crust is not dominated by a massive composite mafic intrusion such as is sometimes inferred for the East African rifts. Seismic and magnetotelluric data suggest the presence of a thin (< 1 km) sill-like contemporary midcrustal magma body which may perhaps extend intermittently along much of the length of the rift. Seismic and structural studies indicate a dominant horizontal fabric in the upper and middle crust. The brittle-ductile transition is at depths -15 km except for the major volcanic fields, where it rises to 2-3 km. Structural development of the rift occurred mainly during two time intervals: the early phase beginning at -30 Ma. and lasting 10-12 m.y., and the late phase extending from -10 to 3 Ma. The early phase involved extensive

  3. Hyacinths Choke the Rio Grande

    NASA Technical Reports Server (NTRS)

    2002-01-01

    These images acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), flying aboard NASA's Terra satellite, demonstrate the potential of satellite-based remote sensors to monitor infestations of non-native plant species. These images show the vigorous growth of water hyacinths along a stretch of the Rio Grande River in Texas. The infestation had grown so dense in some places it was impeding the flow of water and rendered the river impassible for boats. The hyacinth is an aquatic weed native to South America. The plant is exotic looking and, when it blooms, the hyacinth produces a pretty purple flower, which is why it was introduced into North America. However, it has the capacity to grow and spread at astonishing rates so that in the wild it can completely clog the flow of rivers and waterways in a matter of days or weeks. The top image was acquired on March 30, 2002, and the bottom image on May 9, 2002. In the near-infrared region of the spectrum, photosynthetically-active vegetation is highly reflective. Consequently, vegetation appears bright to the near-infrared sensors aboard ASTER; and water, which absorbs near-infrared radiation, appears dark. In these false-color images produced from the sensor data, healthy vegetation is shown as bright red while water is blue or black. Notice a water hyacinth infestation is already apparent on March 30 near the center of the image. By May 9, the hyacinth population has exploded to cover more than half the river in the scene. Satellite-based remote sensors can enable scientists to monitor large areas of infestation like this one rather quickly and efficiently, which is particularly useful for regions that are difficult to reach from on the ground. (For more details, click to read Showdown in the Rio Grande.) Images courtesy Terrametrics; Data provided by the ASTER Science Team

  4. Rio Grande sediment study -- Supply and transport

    SciTech Connect

    Diniz, E.; Eidson, D.; Bourgeois, M.

    1995-12-31

    The 1992 New Mexico State Legislature directed the Interstate Stream Commission (ISC) to study the feasibility of clearing and deepening the channel of the Rio Grande between Albuquerque and Elephant Butte to improve water conveyance and water conservation. The ISC requested the US Army Corps of Engineers-Albuquerque District (COE) to undertake this study under the Planning Assistance to States Program. The study was divided into two phases. Phase 1 consisted of an analysis of the sediment contribution to the Rio grande from the tributaries and an evaluation of the existing US Geological Survey (USGS) sediment gage data. Phase 2 will be an analysis, through the use of an HEC-6, Scour and Deposition in Rivers and Reservoirs, computer model, to determine the long-term performance of any Rio Grande channel improvements. This narrative presents the Phase 1 methods and results.

  5. Middle Rio Grande Cooperative Water Model

    Energy Science and Technology Software Center (ESTSC)

    2005-11-01

    This is computer simulation model built in a commercial modeling product Called Studio Expert, developed by Powersim, Inc. The simulation model is built in a system dynamics environment, allowing the simulation of the interaction among multiple systems that are all changing over time. The model focuses on hydrology, ecology, demography, and economy of the Middle Rio Grande, with Water as the unifying feature.

  6. Rio Grande rift: problems and perspectives

    SciTech Connect

    Baldridge, W.S.; Olsen, K.H.; Callender, J.F.

    1984-01-01

    Topics and ideas addressed include: (1) the regional extent of the Rio Grande rift; (2) the structure of the crust and upper mantle; (3) whether the evidence for an axile dike in the lower crust is compelling; (4) the nature of faulting and extension in the crust; and (5) the structural and magmatic development of the rift. 88 references, 5 figures.

  7. Substance Abuse in the Rio Grande Valley.

    ERIC Educational Resources Information Center

    Zavaleta, Anthony N.

    1979-01-01

    In the Mexican American barrios of Texas' Lower Rio Grande Valley, existence is complicated by the interactive forces of culture, society, and economy. These three factors act in unison to create an etiology of alcohol and drug use and abuse which is poorly understood by persons outside the barrio's grasp. (Author/NQ)

  8. 27 CFR 9.119 - Middle Rio Grande Valley.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Middle Rio Grande Valley... Middle Rio Grande Valley. (a) Name. The name of the viticultural area described in this section is “Middle Rio Grande Valley.” (b) Approved maps. The approved maps for determining the boundaries of...

  9. Upper Rio Grande Simulation Model (URGSIM)

    Energy Science and Technology Software Center (ESTSC)

    2010-08-05

    URGSIM estimates the location of surface water and groundwater resources in the upper Rio Grande Basin between the Colorado-New Mexico state line, and Caballo Reservoir from 1975 - 2045. It is a mass balance hydrology model of the Upper Rio Grande surface water, groundwater, and water demand systems which runs at a monthly timestep from 1975-1999 in calibration mode, 2000 – 2004 in validation mode, and 2005 – 2045 in scenario analysis mode.

  10. Rio Grande pipeline introduces LPG to Mexico

    SciTech Connect

    1997-06-01

    Rio Grande Pipeline, a joint venture between Mid-America Pipeline Co., Amoco Pipeline Co. and Navajo Pipeline Co., has broken new ground in the energy industry as the first LPG pipeline to cross the US-Mexico border. Plans for the project were announced in November 1995 and first deliveries started three months ago on March 21, 1997. The 8-inch, 265-mile pipeline originates near Odessa, TX, where it receives an 85-15 propane-butane mix via a connection to Mid-America Pipeline. From Odessa, product moves west through the Texas desert and crosses the Rio Grande River about 15 miles south of El Paso near Clint, TX and extends 20 miles into Mexico. Capacity of the line is 24,000 bpd and it has been averaging about 22,000 bpd since line-fill. All in all, it sounded like a reasonably feasible, routine project. But perceptions can be deceiving, or at least misleading. In other words, the project can be summarized as follows: one river, two cultures and a world of difference. The official border crossing for pipeline construction took place on Dec. 2, 1996, with a directional drill under the Rio Grande River, but in actuality, the joint venture partners were continually bridging differences in language, laws, customs and norms with Pemex and contracted workers from Mexico.

  11. Raptor Use of the Rio Grande Gorge

    SciTech Connect

    Ponton, David A.

    2015-03-20

    The Rio Grande Gorge is a 115 km long river canyon located in Southern Colorado (15 km) and Northern New Mexico (100 km). The majority of the canyon is under the administration of the Bureau of Land Management {BLM), and 77 km of the canyon south of the Colorado/New Mexico border are designated Wild River under the National Wild and Scenic Rivers Act of 1968. Visits I have made to the Rio Grande Gorge over the past 15 .years disclosed some raptor utilization. As the Snake River Birds of Prey Natural Area gained publicity, its similarity to the Rio Grande Gorge became obvious, and I was intrigued by the possibility of a high raptor nesting density in the Gorge. A survey in 1979 of 20 km of the northern end of the canyon revealed a moderately high density of red-tailed hawks and prairie falcons. With the encouragement of that partial survey, and a need to assess the impact of river-running on nesting birds of prey, I made a more comprehensive survey in 1980. The results of my surveys, along with those of a 1978 helicopter survey by the BLM, are presented in this report, as well as general characterization of the area, winter use by raptors, and an assessment of factors influencing the raptor population.

  12. 75 FR 32359 - Upper Rio Grande Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-08

    ... Forest Service Upper Rio Grande Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Upper Rio Grande Resource Advisory Committee will meet in South Fork... members and Forest Service personnel. (2) Selection of a chairperson by the committee members. (3)...

  13. Simulations of Precipitation Variability over the Upper Rio Grande Basin

    SciTech Connect

    Costigan, Keeley R.; Bossert, James E.; Langley, David L.

    1997-12-31

    In this research, we study Albuquerque`s water and how it may be affected by changes in the regional climate, as manifested by variations in Rio Grande water levels. To do this, we rely on the use of coupled atmospheric, runoff, and ground water models. Preliminary work on the project has focused on uncoupled simulations of the aquifer beneath Albuquerque and winter precipitation simulations of the upper Rio Grande Basin. The latter is discussed in this paper.

  14. 77 FR 8275 - Notice of Meeting, Rio Grande Natural Area Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-14

    ... Bureau of Land Management Notice of Meeting, Rio Grande Natural Area Commission AGENCY: Bureau of Land.... Department of the Interior, Bureau of Land Management (BLM) Rio Grande Natural Area Commission will meet as.... SUPPLEMENTARY INFORMATION: The Rio Grande Natural Area Commission was established in the Rio Grande Natural...

  15. 76 FR 73657 - Notice of Meeting, Rio Grande Natural Area Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-29

    ... Bureau of Land Management Notice of Meeting, Rio Grande Natural Area Commission AGENCY: Bureau of Land.... Department of the Interior, Bureau of Land Management ] (BLM) Rio Grande Natural Area Commission will meet as.... SUPPLEMENTARY INFORMATION: The Rio Grande Natural Area Commission was established in the Rio Grande Natural...

  16. 77 FR 21584 - Notice of Meeting, Rio Grande Natural Area Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-10

    ... Bureau of Land Management Notice of Meeting, Rio Grande Natural Area Commission AGENCY: Bureau of Land.... Department of the Interior, Bureau of Land Management (BLM) Rio Grande Natural Area Commission will meet as.... SUPPLEMENTARY INFORMATION: The Rio Grande Natural Area Commission was established in the Rio Grande Natural...

  17. 78 FR 9729 - Notice of Meeting, Rio Grande Natural Area Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-11

    ... Bureau of Land Management Notice of Meeting, Rio Grande Natural Area Commission AGENCY: Bureau of Land... Interior, Bureau of Land Management (BLM) Rio Grande Natural Area Commission will meet as indicated below.... SUPPLEMENTARY INFORMATION: The Rio Grande Natural Area Commission was established in the Rio Grande Natural...

  18. Thermomechanical models of the Rio Grande rift

    SciTech Connect

    Bridwell, R.J.; Anderson, C.A.

    1980-01-01

    Fully two-dimensional, coupled thermochemical solutions of a continental rift and platform are used to model the crust and mantle structure of a hot, buoyant mantle diapir beneath the Rio Grande rift. The thermomechanical model includes both linear and nonlinear laws of the Weertman type relating shear stress and creep strain rate, viscosity which depends on temperature and pressure, and activation energy, temperature-dependent thermal conductivity, temperature-dependent coefficient of thermal expansion, the Boussinesq approximation for thermal bouyancy, material convection using a stress rate that is invariant to rigid rotations, an elastically deformable crust, and a free surface. The model determines the free surface velocities, solid state flow field in the mantle, and viscosity structure of lithosphere and asthenosphere. Regional topography and crustal heat flow are simulated. A suite of symmetric models, assumes continental geotherms on the right and the successively increasing rift geotherms on the left. These models predict an asthenospheric flow field which transfers cold material laterally toward the rift at > 300 km, hot, buoyant material approx. 200 km wide which ascends vertically at rates of 1 km/my between 175 to 325 km, and spreads laterally away from the rift at the base of the lithosphere. Crustal spreading rates are similar to uplift rates. The lithosphere acts as stiff, elastic cap, damping upward motion through decreased velocities of 1 km/10 my and spreading uplift laterally. A parameter study varying material coefficients for the Weertman flow law suggests asthenospheric viscosities of approx. 10/sup 22/ to 10/sup 23/ poise. Similar studies predict crustal viscosities of approx. 10/sup 25/ poise. The buoyant process of mantle flow narrows and concentrates heat transport beneath the rift, increases upward velocity, and broadly arches the lithosphere. 10 figures, 1 table.

  19. Vigilando la Calidad del Agua de los Grandes Rios de la Nacion: El Programa NASQAN del Rio Grande (Rio Bravo del Norte)

    USGS Publications Warehouse

    Lurry, Dee L.; Reutter, David C.; Wells, Frank C.; Rivera, M.C., (translator); Munoz, A.

    1998-01-01

    La Oficina del Estudio Geologico de los Estados Unidos (U.S. Geological Survey, 0 USGS) ha monitoreado la calidad del agua de la cuenca del Rio Grande (Rio Bravo del Norte) desde 1995 como parte de la rediseiiada Red Nacional para Contabilizar la Calidad del Agua de los Rios (National Stream Quality Accounting Network, o NASOAN) (Hooper and others, 1997). EI programa NASOAN fue diseiiado para caracterizar las concentraciones y el transporte de sedimento y constituyentes quimicos seleccionados, encontrados en los grandes rios de los Estados Unidos - incluyendo el Misisipi, el Colorado y el Columbia, ademas del Rio Grande. En estas cuatro cuencas, el USGS opera actualmente (1998) una red de 40 puntos de muestreo pertenecientes a NASOAN, con un enfasis en cuantificar el flujo en masa (la cantidad de material que pasa por la estacion, expresado en toneladas por dial para cada constituyente. Aplicacando un enfoque consistente, basado en la cuantificacion de flujos en la cuenca del Rio Grande, el programa NASOAN esta generando la informacion necesaria para identificar fuentes regionales de diversos contaminantes, incluyendo sustancias qui micas agricolas y trazas elementos en la cuenca. EI efecto de las grandes reservas en el Rio Grande se puede observar segun los flujos de constituyentes discurren a 10 largo del rio. EI analisis de los flujos de constituyentes a escala de la cuenca proveera los medios para evaluar la influencia de la actividad humana sobre las condiciones de calidad del agua del Rio Grande.

  20. Chemical Contamination of the Lower Rio Grande near Laredo, TX

    NASA Astrophysics Data System (ADS)

    Flores, B.; Ren, J.; Krishnamurthy, S.; Belzer, W.

    2006-12-01

    The Rio Grande River stretches over 2000 miles from the southern Rocky Mountains in Colorado to the tip of Texas where the Rio Grande meets the Gulf of Mexico. It is the natural boundary between U.S. and Mexico from El Paso, TX, to Brownsville, TX. The communities along the border heavily rely upon the Rio Grande as a primary source of water for consumption, agricultural uses, supporting wildlife and recreation. For many years the Rio Grande has been polluted with municipal, industrial, agricultural and farming contaminants from both sides of the border. This pollution has led to the extinction or reduction of certain wildlife species as well as affecting the health of the residences along the border. Even though great strides have been made in monitoring the Rio Grande, there has been a lack of intense monitoring data collection for pollutants such as pesticides. Three sampling sites including Manadas Creek, the Rio Grande River at International Bridge I, and USGS monitoring site 08459200 off of Highway 83 were chosen. The water quality parameters focused include temperature, pH, conductivity, dissolve oxygen (DO), salinity, total dissolved solids, nutrients, metals and pesticides. Preliminary results have shown elevated concentration of total phosphorus and ortho-phosphorus in the Manadas Creek site. Organochlorinated pesticides such as heptachlor and 4, 4 DDE were detected at various concentrations at all sites and endrin aldehyde was found at Manadas Creek site. This research has provided more information on the current chemical contamination level of the Rio Grande in the Laredo area.

  1. Biology of the Rio Grande border region : a bibliography

    USGS Publications Warehouse

    Johnson, Lynne E.; Jacobs, Linda J.; Papoulias, Diana

    1997-01-01

    This bibliography includes 1,913 references to the literature of the Rio Grande (Rio Bravo del Norte). The specific geographic area covered extends 100 km on either side of the river from Elephant Butte Dam in New Mexico to the Gulf of Mexico. The bibliography focuses on the biological literature, divided into major subject areas, and also includes supporting literature from the physical and environmental sciences.

  2. Modeling streamflow from snowmelt in the upper Rio Grande

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Annual snowpack in the high elevation snowsheds of the Upper Rio Grande (URG) Basin is a vital source of surface water for irrigated agriculture in New Mexico. Maximum streamflow from the annual snowpack usually occurs in early May for the southernmost snowsheds (e.g., Ojo Caliente) and at the end o...

  3. 13(a) assessment of the Rio Grande Region. Final report

    SciTech Connect

    Not Available

    1981-09-01

    The report summarizes results of an assessment of water requirements, water availability and other water implications of the development of emerging, nonnuclear energy technologies in the Rio Grande Region. The technologies assessed include advanced coal combustion, geothermal energy, small-scale/low-head hydropower, and enhanced oil recovery.

  4. SNOW: THE REAL WATER SUPPLY FOR THE RIO GRANDE BASIN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Rio Grande basin in Colorado, New Mexico, Texas, and Mexico is an important drainage in southwestern North America, vital for water consumption by a rapidly growing population, irrigated agriculture, economic development, preservation of endangered species, and energy generation. The most impor...

  5. Society and Health in the Lower Rio Grande Valley.

    ERIC Educational Resources Information Center

    Madsen, William

    Shedding light on problems of mental health and illness that have baffled public health workers attempting to improve the health and welfare of Mexican Americans living in the lower Rio Grande Valley, this document reports the folk customs, social organization, medical practices, and beliefs of the Mexican American of this area. Chapters describe…

  6. ASSESSING TRANSBOUNDARY INFLUENCES IN THE LOWER RIO GRANDE VALLEY

    EPA Science Inventory

    The Lower Rio Grande Valley Transboundary Air Pollution Project (TAPP) was a U.S.-Mexico Border XXI Program project to assess transboundary air pollution in and near Brownsville, Texas. The study used a three-site air monitoring network very close to the border to capture the d...

  7. 75 FR 54085 - Divide Ranger District, Rio Grande National Forest; Colorado; Big Moose Vegetation Management...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE Forest Service Divide Ranger District, Rio Grande National Forest; Colorado; Big Moose Vegetation Management Project AGENCY: Forest Service, Rio Grande National Forest, USDA. ACTION: Corrected Notice...

  8. 77 FR 66479 - Notice of Meeting, Rio Grande Natural Area Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-05

    ... Bureau of Land Management Notice of Meeting, Rio Grande Natural Area Commission AGENCY: Bureau of Land.... Department of the Interior, Bureau of Land Management (BLM) Rio Grande Natural Area Commission will meet as... hours. SUPPLEMENTARY INFORMATION: The Rio Grande Natural Area Commission was established in the...

  9. 78 FR 25097 - Notice of Meeting, Rio Grande Natural Area Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-29

    ... Bureau of Land Management Notice of Meeting, Rio Grande Natural Area Commission AGENCY: Bureau of Land... Interior, Bureau of Land Management (BLM) Rio Grande Natural Area Commission will meet as indicated below... business hours. SUPPLEMENTARY INFORMATION: The Rio Grande Natural Area Commission was established in...

  10. 78 FR 52783 - Notice of Meeting, Rio Grande Natural Area Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-26

    ... Bureau of Land Management Notice of Meeting, Rio Grande Natural Area Commission AGENCY: Bureau of Land... Interior, Bureau of Land Management (BLM) Rio Grande Natural Area Commission will meet as indicated below... normal business hours. SUPPLEMENTARY INFORMATION: The Rio Grande Natural Area Commission was...

  11. 77 FR 41798 - Notice of Meeting, Rio Grande Natural Area Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-16

    ... Bureau of Land Management Notice of Meeting, Rio Grande Natural Area Commission AGENCY: Bureau of Land.... Department of the Interior, Bureau of Land Management (BLM) Rio Grande Natural Area Commission will meet as... hours. SUPPLEMENTARY INFORMATION: The Rio Grande Natural Area Commission was established in the...

  12. 78 FR 69127 - Notice of Meeting, Rio Grande Natural Area Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-18

    ... Bureau of Land Management Notice of Meeting, Rio Grande Natural Area Commission AGENCY: Bureau of Land... Interior, Bureau of Land Management (BLM) Rio Grande Natural Area Commission will meet as indicated below... during normal business hours. SUPPLEMENTARY INFORMATION: The Rio Grande Natural Area Commission...

  13. 76 FR 55416 - Notice of Meeting, Rio Grande Natural Area Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-07

    ... relating to non-Federal land in the Rio Grande Natural Area, as directed by law. Planned agenda topics... Bureau of Land Management Notice of Meeting, Rio Grande Natural Area Commission AGENCY: Bureau of Land.... Department of the Interior, Bureau of Land Management (BLM) Rio Grande Natural Area Commission will meet...

  14. Late archaic settlement systems in the northern Rio Grande

    SciTech Connect

    Vierra, Bradley J.

    2003-01-01

    Last year at these meetings I proposed a possible seasonal transhumance pattern for the Late Archaic in the northern Rio Grande region. This pattern involved the movement of groups from the lowland juniper-savanna grasslands in the early summer, to the upland ponderosa pindmixed conifer forests in the mid to late summer, and then back down to the piiion-juniper woodlands during the fall. The Rio Grande Valley was also used for winter habitation sites. Following on this research, I take the next step by studying the inter-assemblage variability represented in a sample of open-air sites located within each of these vegetation communities. The results indicate that there are significant differences in reduction tactics represented between valley habitation vs., upland campsites, and that these site sites are linked together by obsidian procurement patterns.

  15. Seismic Evidence for an Active Southern Rio Grande Rift

    NASA Astrophysics Data System (ADS)

    Thompson, L. E.; Velasco, A. A.

    2010-12-01

    Competing models exist to explain what caused the Earth’s crust to spread apart 29 million years ago to create a region known today as the Rio Grande Rift (RGR). The RGR extends from central Colorado through New Mexico to northern Mexico, near El Paso. A growing body of evidence shows that geologic activity still occurs in the RGR, with a continuation of faulting, seismicity and a small widening rate. We map of the seismic velocity structure and crustal thickness using data from the Rio Grande Rift Seismic TRAnsect (RISTRA) experiment and the EarthScope Transportable Array (USArray) dataset. In addition to the data we collected from the RISTRA experiment and USArray dataset, we also acquired receiver functions from the EarthScope Automatic Receiver Survey (EARS) website (http://www.earthscope.org/data) and waveform data from the Incorporated Research Institutes for Seismology (IRIS) Data Management Center (DMC). In particular, we requested seismograms from the IRIS DMC database where we acquired teleseismic events from Jan 2000 to Dec 2009. This includes 7,259 seismic events with a minimum magnitude of 5.5 and 106,389 continuous waveforms. This data was preprocessed (merged, rotated) using a program called Standing Order of Data (SOD). We computed receiver functions and receiver function stacks for all data in the Southern Rio Grande Rift (SRGR). We map the crustal thickness, seismic velocity, and mantle structure to better determine the nature of tectonic activity that is presently taking place and further investigate the regional extension of the Southern Rio Grande Rift (SRGR). Here we present results of the crustal and velocity structure using the kriging interpolation scheme and interpret our results in relation to southern RGR deformation and extension.

  16. Migrant Worker: A Boy from the Rio Grande Valley.

    ERIC Educational Resources Information Center

    Hoyt-Goldsmith, Diane

    Ricky is an 11-year-old migrant worker. During the summer, he travels with his family from their home in Rio Grande City, Texas, to farms farther north. There they spend 10-12 hours a day in the hot sun picking fruit and vegetables and packing the harvest for market. Ricky is not protected by the federal laws that govern the hours, wages, and…

  17. Symposium: Optics Along The Rio Grande Research Corridor

    NASA Astrophysics Data System (ADS)

    Freese, K.

    1985-11-01

    New Mexico's scientific, technological, and educational resources are concentrated along a 300-mile stretch of the Rio Grande, from Los Alamos in the north to Las Cruces in the south. This area contains two major multidisciplinary national laboratories (Los Alamos and Sandia), three military R&D centers, three state universities, and numerous other technology based organizations, including a growing number of "high-tech" businesses and industries.

  18. Structure of the southern Rio Grande rift from gravity interpretation

    NASA Astrophysics Data System (ADS)

    Daggett, P. H.; Keller, G. R.; Wen, C.-L.; Morgan, P.

    1986-05-01

    Regional Bouguer gravity anomalies in southern New Mexico have been analyzed by two-dimensional wave number filtering and poly-nomial trend surface analysis of the observed gravity field. A prominent, regional oval-shaped positive gravity anomaly was found to be associated with the southern Rio Grande rift. Computer modeling of three regional gravity profiles suggests that this anomaly is due to crustal thinning beneath the southern Rio Grande rift. These models indicate a 25 to 26-km minimum crustal thickness within the rift and suggest that the rift is underlain by a broad zone of anomalously low-density upper mantle. The southern terminus of the anomalous zone is approximately 50 km southwest of El Paso, Texas. A thinning of the rifted crust of 2-3 km relative to the adjacent Basin and Range province indicates an extension of about 9 percent during the formation of the modern southern Rio Grande rift. This extension estimate is consistent with estimates from other data sources. The crustal thinning and anomalous mantle is thought to result from magmatic activity related to surface volcanism and high heat flow in this area.

  19. Field Studies of Geothermal Reservoirs Rio Grande Rift, New Mexico

    SciTech Connect

    James C Witcher

    2002-07-30

    The Rio Grande rift provides an excellent field laboratory to study the nature of geothermal systems in an extensional environment. Much of the geologic complexity that is found in the Basin and Range is absent because the rift is located on cratonic crust with a thin and well-characterized Phanerozoic stratigraphy and tectonic history. On the other hand, the Neogene thermo-tectonic history of the rift has many parallels with the Basin and Range to the west. The geology of the southern Rio Grande rift is among the best characterized of any rift system in the world. Also, most geologic maps for the region are rather unique in that detailed analyses of Quaternary stratigraphic and surficial unit are added in concert with the details of bedrock geology. Pleistocene to Holocene entrenchment of the Rio Grande and tributaries unroofs the alteration signatures and permeability attributes of paleo outflow plumes and upflow zones, associated with present-day, but hidden or ''blind,'' hydrothermal systems at Rincon and San Diego Mountain.

  20. Bottom water throughflows at the Rio de Janeiro and Rio Grande Fracture Zones

    NASA Astrophysics Data System (ADS)

    Mercier, Herlé; Weatherly, Georges L.; Arhan, Michel

    2000-05-01

    Bottom water throughflows at the Rio de Janeiro Fracture Zone (22°S) and Rio Grande Fracture Zone (26°S) of the Mid-Atlantic Ridge are identified from hydrographic anomalies observed along 9°W in the Angola Basin. The throughflow water is supplied by a meridional band of cold and fresh water lying against the western flank of the Ridge.

  1. Microbial contamination and chemical toxicity of the Rio Grande

    PubMed Central

    Mendoza, Jose; Botsford, James; Hernandez, Jose; Montoya, Anna; Saenz, Roswitha; Valles, Adrian; Vazquez, Alejandro; Alvarez, Maria

    2004-01-01

    Background The Rio Grande River is the natural boundary between U.S. and Mexico from El Paso, TX to Brownsville, TX. and is one of the major water resources of the area. Agriculture, farming, maquiladora industry, domestic activities, as well as differences in disposal regulations and enforcement increase the contamination potential of water supplies along the border region. Therefore, continuous and accurate assessment of the quality of water supplies is of paramount importance. The objectives of this study were to monitor water quality of the Rio Grande and to determine if any correlations exist between fecal coliforms, E. coli, chemical toxicity as determined by Botsford's assay, H. pylori presence, and environmental parameters. Seven sites along a 112-Km segment of the Rio Grande from Sunland Park, NM to Fort Hancock, TX were sampled on a monthly basis between January 2000 and December 2002. Results The results showed great variability in the number of fecal coliforms, and E. coli on a month-to-month basis. Fecal coliforms ranged between 0–106 CFU/100 ml while E. coli ranged between 6 to > 2419 MPN. H. pylori showed positive detection for all the sites at different times. Toxicity ranged between 0 to 94% of inhibition capacity (IC). Since values above 50% are considered to be toxic, most of the sites displayed significant chemical toxicity at different times of the year. No significant correlations were observed between microbial indicators and chemical toxicity. Conclusion The results of the present study indicate that the 112-Km segment of the Rio Grande river from Sunland Park, NM to Fort Hancock, TX exceeds the standards for contact recreation water on a continuous basis. In addition, the presence of chemical toxicity in most sites along the 112-Km segment indicates that water quality is an area of concern for the bi-national region. The presence of H. pylori adds to the potential health hazards of the Rio Grande. Since no significant correlation was

  2. Seismic investigation of the southern Rio Grande Rift

    NASA Astrophysics Data System (ADS)

    Thompson, Lennox E.

    Competing models exist to explain what caused the Earth's crust to spread apart 29 million years ago to create a region known today as the Rio Grande Rift (RGR). The RGR extends from central Colorado through New Mexico to northern Mexico, near El Paso. The RGR has different geologic features that distinguish it from most other valleys (e.g., the RGR was not cut by a river nor does a river branch upstream). A growing body of evidence shows that geologic activity still occurs in the RGR, with a continuation of faulting, seismicity and widening at a small rate of about 0.3 mm/yr (Woodward , 1977). We map of the seismic velocity structure and crustal thickness using data from the Rio Grande Rift Seismic TRAnsect (RISTRA) experiment and the EarthScope Transportable Array (USArray) dataset. In addition to the data we collected from the RISTRA experiment and USArray dataset, we also acquired receiver functions from the EarthScope Automatic Receiver Survey (EARS) website (http://www.earthscope.org/data) and waveform data from the Incorporated Research Institutes for Seismology (IRIS) Data Management Center (DMC). We requested seismograms from the IRIS DMC database where we acquired teleseismic events from Jan 2000 to Dec 2009. This includes 7,259 seismic events with a minimum magnitude of 5.5 and 106,389 continuous waveforms. This data was preprocessed (merged, rotated) using a program called Standing Order of Data (SOD). The RISTRA experiment and the USArray were designed to image crust and mantle structures by computing receiver functions for all data in the Southern Rio Grande Rift (SRGR). We map the crustal thickness, seismic velocity, and mantle structure for the sole purpose to better determine the nature of tectonic activity that is presently taking place and further investigate the regional extension of the Southern Rio Grande Rift (SRGR). Here we present preliminary results of the crustal and velocity structure using the kriging interpolation scheme seem stable

  3. 46 CFR 7.105 - Marquesas Keys, FL to Rio Grande, TX.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the seaward limits of the territorial sea (as defined in 33 CFR 2.22(a)(1)) to Rio Grande, Texas at... 46 Shipping 1 2012-10-01 2012-10-01 false Marquesas Keys, FL to Rio Grande, TX. 7.105 Section 7... LINES Gulf Coast § 7.105 Marquesas Keys, FL to Rio Grande, TX. A line drawn from Marquesas Keys,...

  4. 46 CFR 7.105 - Marquesas Keys, FL to Rio Grande, TX.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... the seaward limits of the territorial sea (as defined in 33 CFR 2.22(a)(1)) to Rio Grande, Texas at... 46 Shipping 1 2014-10-01 2014-10-01 false Marquesas Keys, FL to Rio Grande, TX. 7.105 Section 7... LINES Gulf Coast § 7.105 Marquesas Keys, FL to Rio Grande, TX. A line drawn from Marquesas Keys,...

  5. 46 CFR 7.105 - Marquesas Keys, FL to Rio Grande, TX.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the seaward limits of the territorial sea (as defined in 33 CFR 2.22(a)(1)) to Rio Grande, Texas at... 46 Shipping 1 2010-10-01 2010-10-01 false Marquesas Keys, FL to Rio Grande, TX. 7.105 Section 7... LINES Gulf Coast § 7.105 Marquesas Keys, FL to Rio Grande, TX. A line drawn from Marquesas Keys,...

  6. 46 CFR 7.105 - Marquesas Keys, FL to Rio Grande, TX.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the seaward limits of the territorial sea (as defined in 33 CFR 2.22(a)(1)) to Rio Grande, Texas at... 46 Shipping 1 2011-10-01 2011-10-01 false Marquesas Keys, FL to Rio Grande, TX. 7.105 Section 7... LINES Gulf Coast § 7.105 Marquesas Keys, FL to Rio Grande, TX. A line drawn from Marquesas Keys,...

  7. 46 CFR 7.105 - Marquesas Keys, FL to Rio Grande, TX.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the seaward limits of the territorial sea (as defined in 33 CFR 2.22(a)(1)) to Rio Grande, Texas at... 46 Shipping 1 2013-10-01 2013-10-01 false Marquesas Keys, FL to Rio Grande, TX. 7.105 Section 7... LINES Gulf Coast § 7.105 Marquesas Keys, FL to Rio Grande, TX. A line drawn from Marquesas Keys,...

  8. Geomorphology of plutonium in the Northern Rio Grande

    SciTech Connect

    Graf, W.L.

    1993-03-01

    Nearly all of the plutonium in the natural environment of the Northern Rio Grande is associated with soils and sediment, and river processes account for most of the mobility of these materials. A composite regional budget for plutonium based on multi-decadal averages for sediment and plutonium movement shows that 90 percent of the plutonium moving into the system is from atmospheric fallout. The remaining 10 percent is from releases at Los Alamos. Annual variation in plutonium flux and storage exceeds 100 percent. The contribution to the plutonium budget from Los Alamos is associated with relatively coarse sediment which often behaves as bedload in the Rio Grande. Infusion of these materials into the main stream were largest in 1951, 1952, 1957, and 1968. Because of the schedule of delivery of plutonium to Los Alamos for experimentation and weapons manufacturing, the latter two years are probably the most important. Although the Los Alamos contribution to the entire plutonium budget was relatively small, in these four critical years it constituted 71--86 percent of the plutonium in bedload immediately downstream from Otowi.

  9. Intracontinental rift comparisons: Baikal and Rio Grande Rift Systems

    NASA Astrophysics Data System (ADS)

    Lipman, P. W.; Logatchev, N. A.; Zorin, Y. A.; Chapman, C. E.; Kovalenko, V.; Morgan, P.

    Both the Baikal rift in Siberia and the Rio Grande rift in New Mexico, Colorado and Texas are major intracontinental extensional structures of Cenozoic age that affect regions about 1500 km long and several hundred km wide (Figures 1, 2). In the summer of 1988 these rifts were visited by study groups of U.S. and Soviet geoscientists during cooperative field workshops sponsored by the Soviet Academy of Sciences, U.S. National Academy of Sciences, and U.S. Geological Survey.In the Rio Grande region, we spent 2 weeks examining rift features between El Paso, Tex., and Denver, Colo. Particular emphasis was on the sedimentary record of rift evolution, widespread volcanic activity from inception of rifting to the present, geophysical expression of rift features, and relations between rifting and the larger-scale evolution of the North American Cordillera. In the Baikal region, which presents formidable logistic problems for a workshop, we travelled by bus, truck, helicopter, and ship to examine young seismotectonic features, rift-related basalt, and bounding structures of the Siberian craton that influenced rift development (Figure 3).

  10. Female homicide in Rio Grande do Sul, Brazil.

    PubMed

    Leites, Gabriela Tomedi; Meneghel, Stela Nazareth; Hirakata, Vania Noemi

    2014-01-01

    This study aimed to assess the female homicide rate due to aggression in Rio Grande do Sul, Brazil, using this as a "proxy" of femicide. This was an ecological study which correlated the female homicide rate due to aggression in Rio Grande do Sul, according to the 35 microregions defined by the Brazilian Institute of Geography and Statistics (IBGE), with socioeconomic and demographic variables access and health indicators. Pearson's correlation test was performed with the selected variables. After this, multiple linear regressions were performed with variables with p < 0.20. The standardized average of female homicide rate due to aggression in the period from 2003 to 2007 was 3.1 obits per 100 thousand. After multiple regression analysis, the final model included male mortality due to aggression (p = 0.016), the percentage of hospital admissions for alcohol (p = 0.005) and the proportion of ill-defined deaths (p = 0.015). The model have an explanatory power of 39% (adjusted r2 = 0.391). The results are consistent with other studies and indicate a strong relationship between structural violence in society and violence against women, in addition to a higher incidence of female deaths in places with high alcohol hospitalization. PMID:25272258

  11. ASSESSING TRANSBOUNDARY INFLUENCES IN THE LOWER RIO GRANDE VALLEY (COMMUNITY SUMMARY)

    EPA Science Inventory

    The Lower Rio Grande Valley Transboundary Air Pollution Project (TAPP) was done to determine if movement of air pollutants across the U.S.-Mexico border was occurring in the Lower Rio Grande Valley (hereinafter called "the Valley") and, if so, the extent. The study w...

  12. 33 CFR 80.850 - Brazos River, TX to the Rio Grande, TX.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Brazos River, TX to the Rio Grande, TX. 80.850 Section 80.850 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Eighth District § 80.850 Brazos River, TX to the Rio Grande, TX. (a) Except...

  13. 75 FR 7625 - Endangered and Threatened Wildlife and Plants; Rio Grande Silvery Minnow (Hybognathus amarus...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-22

    ... Rio Grande silvery minnow was listed as federally endangered in 1994 (July 20, 1994; 59 FR 36988) and critical habitat was designated in 2003 (February 19, 2003; 68 FR 8087). The species was extirpated from... (mi)) reach of the Rio Grande River in New Mexico, downstream of Cochiti Dam to the headwaters...

  14. 76 FR 39120 - Notice of Meeting, Rio Grande Natural Area Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-05

    .../co/frrac/co_fr.htm . Dated: June 28, 2011. Anna Marie Burden, Acting State Director. BILLING CODE... Bureau of Land Management Notice of Meeting, Rio Grande Natural Area Commission AGENCY: Bureau of Land.... Department of the Interior, Bureau of Land Management (BLM) Rio Grande Natural Area Commission will meet...

  15. Remote Sensing of Exotic Invasive Weeds in the Rio Grande System of Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Exotic invasive weeds are a serious problem in the Rio Grande system of Texas. This paper presents the results of several aerial remote sensing studies conducted from 2002 to 2006 on the Rio Grande from its mouth near Brownsville in south Texas to El Paso in west Texas. Weed species addressed inc...

  16. Bryozoans from rio grande do sul continental shelf, southern Brazil.

    PubMed

    Ramalho, Laís V; Calliari, Lauro

    2015-01-01

    The continental shelf of Rio Grande do Sul (RS) is predominantly composed of unconsolidated sediments with a few hard substrates represented principally by beachrock. In this area there are elongate deposits of shell gravel material which are interpreted as indicators of the palaeo-shorelines. These Pleistocene deposits are overlapped by Holocene sediments (Recent), but are exposed during erosive events caused by extra-tropical cyclones, which provide the mixture of both sediments mainly during autumn and winter. The few studies on bryozoans made in this area previously recorded seven species, one fossil and the other six from Recent fluvial and marine environments. The aim of the present study was to describe the eight most abundant bryozoan species that occur in the inner RS shelf. Of these, four are new records for RS State (Arachnopusia aff. pusae, Hippomonavella brasiliensis, Turbicellepora pourtalesi, and Lifuella gorgonensis), and the other four are new to science (Chaperia taylori, Micropora nodimagna, Cellaria riograndensis, and Exochella moyani). PMID:25947873

  17. STEM education for teachers in the Rio Grande Valley

    NASA Astrophysics Data System (ADS)

    Ries, Judit Gyorgyey; Baguio, Margaret R.

    2015-11-01

    We have worked with elementary and middle school teachers in the Rio Grande Valley for the last 10 years bringing Earth and Space Science themed workshops to underserved areas of Texas. The Texas curriculum was also changed to include Astronomy and Space Science requirement in the tests students need to take to prove their academic preparedness. The teachers worked through a variety of inquiry-based, hands-on activities after a short presentation on the background science. In order to evaluate our effectiveness, we have asked the teachers to take pre- and post-workshop tests, and we asked them to fill out a self-reflective survey. We will report on our experiences, what works best with the teachers, and in what areas we still have a long way to go.This work was supported by various NASA education grants and Cooperative agreements, as well as grants provided by the Texas Space Grant Consortium.

  18. A groundwater convection model for Rio Grande rift geothermal resources

    NASA Technical Reports Server (NTRS)

    Morgan, P.; Harder, V.; Daggett, P. H.; Swanberg, C. A.

    1981-01-01

    It has been proposed that forced convection, driven by normal groundwater flow through the interconnected basins of the Rio Grande rift is the primary source mechanism for the numerous geothermal anomalies along the rift. A test of this concept using an analytical model indicates that significant forced convection must occur in the basins even if permeabilities are as low as 50-200 millidarcies at a depth of 2 km. Where groundwater flow is constricted at the discharge areas of the basins forced convection can locally increase the gradient to a level where free convection also occurs, generating surface heat flow anomalies 5-15 times background. A compilation of groundwater data for the rift basins shows a strong correlation between constrictions in groundwater flow and hot springs and geothermal anomalies, giving strong circumstantial support to the convection model.

  19. Magnetotelluric pilot study in the Rio Grande Rift, southwest USA

    NASA Astrophysics Data System (ADS)

    Feucht, D. W.; Bedrosian, P. A.; Sheehan, A. F.

    2012-12-01

    A magnetotelluric (MT) pilot study consisting of approximately 25 stations distributed in and around the Rio Grande Rift of the southwest United States was carried out in the summer of 2012. Both broadband (100 Hz to 1000 s) and long-period (up to 10 000 s) MT data were collected across two profiles that run perpendicular to the rift axis near Denver, Colorado and Taos, New Mexico, respectively. Time-domain EM data was also collected at each site to account for galvanic distortion in the near-surface. The tectonic forces and rheologic properties behind the initiation and propagation of the rift are poorly understood. Surface mapping of volcanism, normal faulting and sedimentary basins reveals a narrow band of crustal deformation confined to a region in close proximity to the rift axis while geophysical results suggest that deformation is distributed across a much broader and deeper region of the lithosphere. In particular, seismic tomography shows low seismic wave speeds into the lower crust and upper mantle. The magnetotelluric technique is a well-proven passive electromagnetic method that allows for the detection of apparent resistivity at a wide range of depth scales. Complimenting the seismic results with MT data will provide important new information on the geologic and geophysical properties that control the rifting process in this low-strain rate environment. Properties to which the MT method is particular sensitive include temperature, fluid content, and mineral alteration. Preliminary results from this most recent survey are encouraging, showing good data quality up to 10 000 s. In an important precursor to full 2D modeling, the magnetotelluric phase tensor has been used to assess the dimensionality of the electrical resistivity structure at depth. This pilot study provides proof of concept for a much larger magnetotelluric experiment planned to take place in the Rio Grande Rift in 2013.

  20. View of northeastern Mexico and the Rio Grande Valley of Texas

    NASA Technical Reports Server (NTRS)

    1973-01-01

    An oblique view of northeastern Mexico and the Rio Grande Valley of Texas (26.0N,100.0W), as photographed from the Skylab space station by one of the Skylab 4 crewmen. Mexico's Sierra Madre Oriental Mountains are in the center of the picture. The Gulf of Mexico is in the background. Note the lakes on the Rio Grande River. Monterrey is near the center of the picture. Field patterns in the lower Rio Grande Valley can easily be identified. The stark, linear roughness of the Sierra Madre Oriental Mountains is the most prominent feature.

  1. Extreme Drought Conditions in the Rio Grande/Bravo Basin

    NASA Astrophysics Data System (ADS)

    Gutiérrez, F.; Dracup, J. A.

    2001-12-01

    The Treaty of February 3, 1944 entitled "Utilization of Waters of the Colorado and Tijuana Rivers and of the Rio Grande" between the U.S. and Mexico regulates the distribution of flows of the rivers between these two countries. The treaty is based on hydrological data available up to 1944. Using new (historical and paleoclimatological) data, the water balance presented in the Treaty is re-examinated and the 431,721,000 m3/year allocation for USA during "extreme drought conditions" is re-evaluated. The authors define "extreme drought conditions" for this basin and a hydrological drought analysis is carried out using a streamflow simulation model. The analysis is complemented with an analysis of the effects of the El Niño - Southern Oscillation and the Pacific Decadal Oscillation on precipitation and streamflow. The results of this research will be applicable to potential changes in the current water resources management policies on the basin. Given the social, economical and political importance of this basin, the findings of this research potentially will have significant impacts. This research is founded by the NSF fund SAHRA (Science and Technology Center to study and promote the "Sustainability of Water Resources in Semi-Arid Regions" at the University of Arizona).

  2. Upwarp of anomalous asthenosphere beneath the Rio Grande rift

    USGS Publications Warehouse

    Parker, E.C.; Davis, P.M.; Evans, J.R.; Iyer, H.M.; Olsen, K.H.

    1984-01-01

    Continental rifts are possible analogues of mid-ocean ridges, although major plate tectonic features are less clearly observed1. Current thermal models of mid-ocean ridges2-4 consist of solid lithospheric plates overlying the hotter, less viscous asthenosphere, with plate thickness increasing away from the ridge axis. The lithospheric lower boundary lies at or near the melting point isotherm, so that at greater depths higher temperatures account for lower viscosity, lower seismic velocities and possibly partial melting. Upwarp of this boundary at the ridge axis concentrates heat there, thus lowering densities by expansion and raising the sea floor to the level of thermal isostatic equilibrium. At slow spreading ridges, a major central graben forms owing to the mechanics of magma injection into the crust5. Topography, heat flow, gravity and seismic studies support these models. On the continents, a low-velocity channel has been observed, although it is poorly developed beneath ancient cratons6-9. Plate tectonic models have been applied to continental basins and margins10-12, but further similarities to the oceanic models remain elusive. Topographic uplift is often ascribed to Airy type isostatic compensation caused by crustal thickening, rather than thermal compensation in the asthenosphere. Here we discuss the Rio Grande rift, in southwestern United States. Teleseismic P-wave residuals show that regional uplift is explained by asthenosphere uplift rather than crustal thickening. ?? 1984 Nature Publishing Group.

  3. Hydrological and Meteorological Disturbances in Rio Grande Riparian Ecosystems

    NASA Astrophysics Data System (ADS)

    Thibault, J. R.; Cleverly, J. R.; Dahm, C.

    2012-12-01

    Invasive species and ecohydrological disturbances are imperiling native riparian ecosystems. Adaptable, resilient exotic competitors including tamarisk have colonized many waterways in the western US. Alteration of the natural flow regime due to water diversions is expected to be exacerbated by climate change in this region, confounding restoration efforts. Climate change may also increase the likelihood of other disturbances, including extreme weather events (drought, floods, temperatures). We investigate how hydrological and meteorological variability impact water use by tamarisk communities that have overtaken native riparian vegetation. We have collected more than a decade of complete growing season eddy covariance evapotranspiration (ET) and water table (WT) elevation data at two sites along the Rio Grande corridor of central New Mexico, USA. Conditions have ranged from extreme drought to exceedingly wet years with extensive overbank flooding, and from record setting warm to cold temperatures. Severe to extreme droughts persisted throughout 2002 and 2003. Abundant snowpacks and wetter conditions led to extensive flooding early in the 2005 and 2008 growing seasons. Along with a return to intense drought conditions, extreme temperatures struck New Mexico in 2011. A deep freeze in early February followed by an extraordinarily late, extended hard freeze at the onset of the growing season was then succeeded by the warmest summer in the state's 117 year record. We present how water use by the replacement communities responds to droughts, flooding, and extreme temperatures, all of which are expected to increase in frequency, and speculate how these disturbances will affect native riparian ecosystems.

  4. Geographic distribution of genetic diversity in populations of Rio Grande Chub Gila pandora

    USGS Publications Warehouse

    Galindo, Rene; Wilson, Wade; Caldwell, Colleen A.

    2016-01-01

    In the southwestern United States (US), the Rio Grande chub (Gila pandora) is state-listed as a fish species of greatest conservation need and federally listed as sensitive due to habitat alterations and competition with non-native fishes. Characterizing genetic diversity, genetic population structure, and effective number of breeders will assist with conservation efforts by providing a baseline of genetic metrics. Genetic relatedness within and among G. pandora populations throughout New Mexico was characterized using 11 microsatellite loci among 15 populations in three drainage basins (Rio Grande, Pecos, Canadian). Observed heterozygosity (HO) ranged from 0.71–0.87 and was similar to expected heterozygosity (0.75–0.87). Rio Ojo Caliente (Rio Grande) had the highest allelic richness (AR = 15.09), while Upper Rio Bonito (Pecos) had the lowest allelic richness (AR = 6.75). Genetic differentiation existed among all populations with the lowest genetic variation occurring within the Pecos drainage. STRUCTURE analysis revealed seven genetic clusters. Populations of G. pandora within the upper Rio Grande drainage (Rio Ojo Caliente, Rio Vallecitos, Rio Pueblo de Taos) had high levels of admixture with Q-values ranging from 0.30–0.50. In contrast, populations within the Pecos drainage (Pecos River and Upper Rio Bonito) had low levels of admixture (Q = 0.94 and 0.87, respectively). Estimates of effective number of breeders (N b ) varied from 6.1 (Pecos: Upper Rio Bonito) to 109.7 (Rio Grande: Rio Peñasco) indicating that populations in the Pecos drainage are at risk of extirpation. In the event that management actions are deemed necessary to preserve or increase genetic diversity of G. pandora, consideration must be given as to which populations are selected for translocation.

  5. 78 FR 57411 - Second Call for Nominations for the Rio Grande Natural Area Commission, CO

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-18

    ... request public nominations for a vacancy on the Rio Grande Natural Area Commission (Commission). The nine....C. 460rrr-2). The Commission shall be composed of nine members appointed by the Secretary, of...

  6. Workshop on The Rio Grande Rift: Crustal Modeling and Applications of Remote Sensing

    NASA Technical Reports Server (NTRS)

    Blanchard, D. P. (Editor)

    1980-01-01

    The elements of a program that could address significant earth science problems by combining remote sensing and traditional geological, geophysical, and geochemical approaches were addressed. Specific areas and tasks related to the Rio Grande Rift are discussed.

  7. Plutonium and the Rio Grande: Environmental change and contamination in the nuclear age

    SciTech Connect

    Graf, W.L.

    1994-12-31

    An attempt is made to analyze questions concerning the issue of plutonium in the Rio Grande. The author describes in great detail how he arrived at the conclusions. The objective has been to produce research that is absolutely transparent, so that its results can be fairly evaluated and duplicated by anyone. The results of this work show that plutonium from Los Alamos National Laboratory and atmospheric fallout has been deposited along the Rio Grande in small, though detectable, quantities in certain predictable places.

  8. A Confluence of Community: Gathering the Waters of the Rio Grande.

    ERIC Educational Resources Information Center

    Smith, Craig

    2001-01-01

    A Gathering of Waters is a community-based art and activism project to raise awareness that the Rio Grande/Rio Bravo is a desperately endangered river, connect communities dependent on the river, and galvanize those communities into action. Activities provided actual and symbolic experiences of river water for American Indian, Hispanic, Anglo, and…

  9. LOWER RIO GRANDE VALLEY TRANSBOUNDARY AIR POLLUTION PROJECT (TAPP) (MAIN REPORT)

    EPA Science Inventory

    The purpose of the Lower Rio Grande Valley Transboundary Air Pollution Project (TAPP) was to obtain air quality data for a full year at three border monitoring sites to assess anthropogenic and biogenic emission impacts and transboundary air pollution transport in the Lower Rio...

  10. U and Sr Isotope Tracers of Agricultural Salinity Sources to the Lower Rio Grande River

    NASA Astrophysics Data System (ADS)

    Nyachoti, S. K.; Ma, L.; Szynkiewicz, A.; Jin, L.; McIntosh, J. C.

    2014-12-01

    Elevated salinity of the lower Rio Grande River deteriorates water quality and limits domestic and agricultural water use. Both natural and anthropogenic processes contribute salts in the Rio Grande. Previous studies have focused on natural salt contributions with less emphasis on anthropogenic sources of salinity in the Rio Grande. Using (234U/238U) activity ratios (UAR), 87Sr/86Sr isotope ratios, and major element concentrations, we aim to trace and quantify the salt loads in the Lower Rio Grande watershed which is greatly impacted by agricultural activities. Between 2009 and 2010, we sampled the Rio Grande stretch and irrigation return flows between the Elephant Butte Reservoir, New Mexico and El Paso, Texas. Furthermore, we monitored in monthly intervals the temporal changes of chemical and isotopic compositions of the Rio Grande at Canutillo, Tx. Our results show higher U and Sr fluxes in the Rio Grande during the irrigation season as compared to the non-irrigation season. The UAR (1.62 to 2.13) and 87Sr/86Sr ratios (0.7099 to 0.7138) were higher in the non-irrigation season compared to the irrigation season (UAR: 1.69 to 1.77; 87Sr/86Sr: 0.7100 to 0.7106). These variations of UAR and 87Sr/86Sr ratios imply multiple sources of U and Sr in the Rio Grande. In contrast, the agricultural return flows show a narrow range of UAR (1.31 to 1.37) and 87Sr/86Sr ratios (0.7091 to 0.7099) in the studied seasons. This is consistent with salinity contributions from agricultural sources. Rio Grande at Canutillo shows low UAR (1.62 to 1.77) and 87Sr/86Sr ratios (0.7104 to 0.7105) during the irrigation season as compared to the non-irrigation season (UAR: 2.04 to 2.24; 87Sr/86Sr: 0.7105 to 0.7109). The low U and Sr signature at Canutillo during the irrigation season is close to that of the agricultural return flows, indicative of agricultural salinity sources. These results provide useful elemental and isotopic constraints for future mass balance calculations of salinity

  11. Trace elements and organic compounds associated with riverbed sediments in the Rio Grande/Rio Bravo basin, Mexico and Texas

    USGS Publications Warehouse

    Lee, R.W.; Wilson, J.T.

    1997-01-01

    In 1991, the Texas Natural Resource Conservation Commission (TNRCC) was mandated by the Texas Clean Rivers Act (Senate Bill 818) to assess water quality of rivers in Texas. Recent efforts to collect information for the assessment of water quality in the Rio Grande/Rio Bravo Basin have involved Federal agencies on both sides of the 1,248-mile U.S.-Mexico border?U.S. Environmental Protection Agency, U.S. Geological Survey (USGS), Secretaria de Desarollo Social (Secretary for Social Development, Mexico), National Water Commission of Mexico, and International Boundary and Water Commission?as well as State and local agencies in a spirit of international cooperation. Substantial efforts have been made to gather data needed to determine the quality of water and ecological status of the Rio Grande/Rio Bravo, especially at sites along the border (fig. 1). The purpose of this report is to assess selected historical data of trace elements and organic compounds in riverbed sediments of the Rio Grande/Rio Bravo, and of the Pecos River and the Arroyo Colorado in Texas.

  12. Evaluation of canoe surveys for anurans along the Rio Grande in Big Bend National Park, Texas

    USGS Publications Warehouse

    Jung, R.E.; Bonine, K.E.; Rosenshield, M.L.; de la Reza, A.; Raimondo, S.; Droege, S.

    2002-01-01

    Surveys for amphibians along large rivers pose monitoring and sampling problems. We used canoes at night to spotlight and listen for anurans along four stretches of the Rio Grande in Big Bend National Park, Texas, in 1998 and 1999. We explored temporal and spatial variation in amphibian counts and species richness and assessed relationships between amphibian counts and environmental variables, as well as amphibian-habitat associations along the banks of the Rio Grande. We documented seven anuran species, but Rio Grande leopard frogs (Rana berlandieri) accounted for 96% of the visual counts. Chorus surveys along the river detected similar or fewer numbers of species, but orders of magnitude fewer individuals compared to visual surveys. The number of species varied on average by 37% across monthly and nightly surveys. We found similar average coefficients of variation in counts of Rio Grande leopard frogs on monthly and nightly bases (CVs = 42-44%), suggesting that canoe surveys are a fairly precise technique for counts of this species. Numbers of Rio Grande leopard frogs observed were influenced by river gage levels and air and water temperatures, suggesting that surveys should be conducted under certain environmental conditions to maximize counts and maintain consistency. We found significant differences in species richness and bullfrog (Rana catesbeiana) counts among the four river stretches. Four rare anuran species were found along certain stretches but not others, which could represent either sampling error or unmeasured environmental or habitat differences among the river stretches. We found a greater association of Rio Grande leopard frogs with mud banks compared to rock or cliff (canyon) areas and with seepwillow and open areas compared to giant reed and other vegetation types. Canoe surveys appear to be a useful survey technique for anurans along the Rio Grande and may work for other large river systems as well.

  13. A lithospheric investigation of the Southern Rio Grande Rift

    NASA Astrophysics Data System (ADS)

    Averill, Matthew George

    2007-12-01

    The crustal structure of the Rio Grande Rift is an important link to the understanding of mantle, crustal and surface processes associated with continental rift environments. We present a model for the crustal velocity structure of the rift derived from the analysis of seismic refraction/wide-angle reflection data acquired during the Potrillo Volcanic Field (PVF) experiment in May 2003. The 205 km long profile, consisting of 8 shots and 793 receivers across southern New Mexico and Far West Texas, was designed as a detailed seismic investigation of the structure and composition of the Southern Rio Grande Rift (SRGR) and the Potrillo Volcanic field, a very recent and well-known xenolith locale. Our results provide several new insights into the structure of the SRGR, including: (1) A new detailed cross-section of the basins and range structure across southern New Mexico into Far West Texas; (2) evidence for slightly thicker crust (˜30--31 km) in the SRGR than previously modeled with little overall topography on the Moho; (3) a highly complex upper-crustal velocity structure underlying the PVF, that includes several high velocity bodies between 5 and 10 km depth; (4) increased seismic reflectivity within the crust and at the Moho interface concentrated below the PVF and; (5) a dramatic step in a mid-crustal interface from west to east indicating a thickening of the mid-crust below the PVF. Interpretation of our velocity results is complimented by use gravity modeling, magnetic and heat flow data and xenolith studies. Furthermore, the resolution of our model has been analyzed using a new approach to determine velocity uncertainty in tomographic modeling. Along the profile, the velocity structure of the upper 3--5 km reflects the basins and ranges of this recently extended area. Basin fill ranges in velocity from 2.5 to 4.5 km/s. In the ranges, velocities are 4.7 to 5.3 km/s and reflect uplifted Paleozoic sedimentary rock. A middle crust interface marks the transition

  14. Monitoring The Water Quality of the Nation's Large Rivers: Rio Grande NASQAN Program

    USGS Publications Warehouse

    Lurry, Dee L.; Reutter, David C.; Wells, Frank C.

    1998-01-01

    The U.S. Geological Survey (USGS) has monitored the water quality in the Rio Grande Basin as part of the redesigned National Stream Quality Accounting Network (NASQAN) since 1995 (Hooper and others, 1997). The NASQAN program was designed to characterize the concentrations and transport of sediment and selected chemical constituents found in the Nation's large rivers-including the Mississippi, Colorado, and Columbia in addition to the Rio Grande. In these four basins, the USGS currently (1998) operates a network of 40 NASQAN sites, with an emphasis on quantifying the mass flux for each constituent (the amount of material moving past the site, expressed in tons per day). By applying a consistent flux-based approach in the Rio Grande Basin, the NASQAN program is generating the information needed to identify regional sources for a variety of constituents, including agricultural chemicals and trace elements, in the basin. The effect of the large reservoirs on the Rio Grande can be observed as constituent fluxes are routed downstream. The analysis of constituent fluxes on a basin-wide scale will provide the means to assess the influence of human activity on water-quality conditions in the Rio Grande.

  15. Paleohydraulic interpretation and morphologic reconstruction of the northern Rio Grande River, Colorado

    SciTech Connect

    Muriceak, D.R. . Geosciences Dept.)

    1993-03-01

    A flight of unpaired late Quaternary terraces comprised of fluvio-glacial deposits flanks the northern Rio Grande River for nearly ten miles along the upper Rio Grande valley. These terraces, which occur at decreasing heights due to progressive valley incision, are comprised of sediments that represent aggradation by braided streams flowing from the terminus of valley glaciers that flowed down the upper Rio Grande at least twice during late Quaternary time. Terminal moraines that are equivalent to Pinedale and Bull Lake stages of ice advance occur at the upstream origin of the terraces. Incision of the Rio Grande river since Pinedale time has resulted in at least three cut terraces that converge downstream. The purpose of this report is to reconstruct the Quaternary history of the Rio Grande river valley during its transition from full glacial to interglacial conditions. A total geodetic station provided coordinate and elevation data to correlate the terraces, extrapolate channel geometry through cross sections, and construct longitudinal profiles of the individual terrace surfaces. Measurements of the B-axis length of boulders on both terrace tread surfaces and surfaces within the terrace deposits were used to reconstruct paleoflow hydrology. The coarsest channel morphological features, too large to be deposited by normal glacial outwash, were deposited during a catastrophic outburst flood (after the failure of an ice dammed lake) that produced high discharge.

  16. Creating a standardized watersheds database for the lower Rio Grande/Rio Bravo, Texas

    USGS Publications Warehouse

    Brown, Julie R.; Ulery, Randy L.; Parcher, Jean W.

    2000-01-01

    This report describes the creation of a large-scale watershed database for the lower Rio Grande/Rio Bravo Basin in Texas. The watershed database includes watersheds delineated to all 1:24,000-scale mapped stream confluences and other hydrologically significant points, selected watershed characteristics, and hydrologic derivative datasets. Computer technology allows generation of preliminary watershed boundaries in a fraction of the time needed for manual methods. This automated process reduces development time and results in quality improvements in watershed boundaries and characteristics. These data can then be compiled in a permanent database, eliminating the time-consuming step of data creation at the beginning of a project and providing a stable base dataset that can give users greater confidence when further subdividing watersheds. A standardized dataset of watershed characteristics is a valuable contribution to the understanding and management of natural resources. Vertical integration of the input datasets used to automatically generate watershed boundaries is crucial to the success of such an effort. The optimum situation would be to use the digital orthophoto quadrangles as the source of all the input datasets. While the hydrographic data from the digital line graphs can be revised to match the digital orthophoto quadrangles, hypsography data cannot be revised to match the digital orthophoto quadrangles. Revised hydrography from the digital orthophoto quadrangle should be used to create an updated digital elevation model that incorporates the stream channels as revised from the digital orthophoto quadrangle. Computer-generated, standardized watersheds that are vertically integrated with existing digital line graph hydrographic data will continue to be difficult to create until revisions can be made to existing source datasets. Until such time, manual editing will be necessary to make adjustments for man-made features and changes in the natural landscape

  17. Investigation of rifting processes in the Rio Grande Rift using data from unusually large earthquake swarms

    SciTech Connect

    Sanford, A.; Balch, R.; House, L.; Hartse, H.

    1995-12-01

    San Acacia Swarm in the Rio Grande Rift. Because the Rio Grande rift is one of the best seismically instrumented rift zones in the world, studying its seismicity provides an exceptional opportunity to explore the active tectonic processes within continental rifts. We have been studying earthquake swarms recorded near Socorro in an effort to link seismicity directly to the rifting process. For FY94, our research has focused on the San Acacia swarm, which occurred 25 km north of Socorro, New Mexico, along the accommodation zone between the Albuquerque-Belen and Socorro basins of the central Rio Grande rift. The swarm commenced on 25 February 1983, had a magnitude 4.2 main shock on 2 March and ended on 17 March, 1983.

  18. DDE mercury, and selenium in Biota, sediments, and water of the Rio Grande-Rio Bravo Basin, 1965-1995.

    PubMed

    Mora, M A; Wainwright, S E

    1998-01-01

    An assessment of contaminant stressors on biota of the Rio Grande was conducted to identify relevant contaminant issues, assess exposure and ecological effects, identify data gaps, and determine potential risks. Most contaminant data were from studies conducted during 1965-1995 in the Lower Rio Grande, on the Texas side of the river, within a 100-km boundary from Falcon Dam to the mouth. Contaminants most frequently reported were organochlorine compounds (OCs) and trace elements. The number of records for OCs and trace elements was at least twofold greater for fish than for birds, mammals, or reptiles. Of the OCs, p,p'-DDE was the most commonly reported. Among the trace elements, Hg was one of the most frequently reported; however, Se, As, Pb, Cu, and Zn were also common. The highest concentrations of OCs and trace elements were reported predominantly from Lower Rio Grande Valley locations, with approximately 68% of the highest values detected from Falcon Dam to the mouth of the river. Twenty-six (20%) of the locations with maximum concentrations corresponded to portions of Llano Grande Lake and the Arroyo Colorado. Recent analyses of birds and fish indicate that levels of DDE are currently much lower than in the 1970s or 1980s in Rio Grande wildlife. This apparent decline does not apply to Hg and Se levels in birds and fish, which have remained more or less constant, but may have increased over the years in some locations. Hg was of particular concern because of high levels found recently in addled eggs of aplomado falcons and in their potential prey. Hg was elevated in fish from the Big Bend area. Also, Se in fish sampled in 1993 and 1994 was near or above the threshold for potential effects in fish-eating wildlife. Future investigations should evaluate the potential impacts of Hg and Se on aquatic and terrestrial species from selected sites of concern. PMID:9751032

  19. New evidence for magmatic intrusion beneath the Rio Grande rift, New Mexico.

    USGS Publications Warehouse

    Towle, J.N.

    1980-01-01

    An analysis of the geomagnetic variation field across the Rio Grande rift has identified two concentrations of telluric current flow beneath the rift caused by channeling of telluric currents in electrically conductive structures in the crust and upper mantle. A shallow conductor nearly coincides with a very strong reflection in a high-resoltuion seismic-reflection profile across the central Rio Grande graben which has been attributed to a lens at mid-crustal depth. The deep (more than 30 km) conductor is 200 km wide and may indicate anomalously high temperatures and, by inference, a thinning of the lithosphere beneath the rift.-Authors

  20. Mesohabitats, fish assemblage composition, and mesohabitat use of the Rio Grande silvery minnow over a range of seasonal flow regimes in the Rio Grande/Rio Bravo del Norte, in and near Big Bend National Park, Texas, 2010-11

    USGS Publications Warehouse

    Moring, J. Bruce; Braun, Christopher L.; Pearson, Daniel K.

    2014-01-01

    In 2010–11, the U.S. Geological Survey (USGS), in cooperation with the U.S. Fish and Wildlife Service, evaluated the physical characteristics and fish assemblage composition of mapped river mesohabitats at four sites on the Rio Grande/Rio Bravo del Norte (hereinafter Rio Grande) in and near Big Bend National Park, Texas. The four sites used for the river habitat study were colocated with sites where the U.S. Fish and Wildlife Service has implemented an experimental reintroduction of the Rio Grande silvery minnow (Hybognathus amarus), a federally listed endangered species, into part of the historical range of this species. The four sites from upstream to downstream are USGS station 08374340 Rio Grande at Contrabando Canyon near Lajitas, Tex. (hereinafter the Contrabando site), USGS station 290956103363600 Rio Grande at Santa Elena Canyon, Big Bend National Park, Tex. (hereinafter the Santa Elena site), USGS station 291046102573900 Rio Grande near Ranger Station at Rio Grande Village, Tex. (hereinafter the Rio Grande Village site), and USGS station 292354102491100 Rio Grande above Stillwell Crossing near Big Bend National Park, Tex. (hereinafter the Stillwell Crossing site). In-channel river habitat was mapped at the mesohabitat scale over a range of seasonal streamflows. A late summer (August–September 2010) high-flow regime, an early spring (April–May 2010) intermediate flow regime, and a late spring (May 2011) low-flow regime were the seasonal flows used in the study. River habitat was mapped in the field by using a geographic information system and a Global Positioning System unit to characterize the sites at the mesohabitat scale. Physical characteristics of a subset of mesohabitats in a reach of the Rio Grande at each site were measured during each flow regime and included depth, velocity, type and size of the substrate, and percent embeddedness. Selected water-quality properties (dissolved oxygen, pH, specific conductance, and temperature) of a subset of

  1. Water Management for Competing Uses: Environmental Flows in the Transboundary Rio Grande/Rio Bravo

    NASA Astrophysics Data System (ADS)

    Sandoval Solis, S.; McKinney, D. C.

    2011-12-01

    Introduction Due to high water demand, the scarcity of water, and the complexity of water allocation, environmental flows have not been considered as an integral part of the water management in the Rio Grande/Rio Bravo transboundary basin. The Big Bend reach is located between the cities of Presidio/Ojinaga to Amistad international reservoir, along the main stream (Fig. 1). Important environmental habitats such as the Big Bend National and State Park in the U.S., the Maderas del Carmen, Cañon de Santa Elena and Ocampo natural reserved areas in Mexico are ecologically threatened because of the lack of environmental water management policies. Several efforts have been undertaken by scientists, government agencies and NGOs to determine the environmental flows for this reach and water management policies that can provide these flows. Objective The objective of this research is to describe a water management policy that can conciliate environmental and human water uses in the Big Bend region. In other words, define a policy that can provide environmental flows without harming water supply for stakeholders or increasing flood risk, within legal and physical constraints of the system. Methodology First, the system was characterized identifying water users, hydraulic infrastructure, and water allocation according to state, federal and international regulations. Second, a hydrograph for environmental flows was proposed that mimics the hydrologic characteristics of the prior dam alteration. Third, a water planning model was constructed to evaluate alternative policies. Fourth, the water management is proposed to provide environmental restoration flows from Luis L. Leon reservoir. This policy considers mechanisms that reduce flooding and drought risks, while meting national and international water regulations. Results Three types of natural flow regimes are considered: (1) median flows aimed to provide the base flow in the region, (2) high flows to provide transversal

  2. Water-quality trends in the Rio Grande/Rio Bravo Basin using sediment cores from reservoirs

    USGS Publications Warehouse

    Van Metre, Peter C.; Mahler, B.J.; Callender, Edward C.

    1997-01-01

    In 1991, the U.S. Geological Survey (USGS) began full implementation of the National Water-Quality Assessment (NAWQA) Program (Leahy and others, 1990). Also in 1991, the State of Texas established the Clean Rivers Program (CRP) administered by the Texas Natural Resource Conservation Commission (TNRCC). The coring study reported here was a collaborative effort between the NAWQA Program and the CRP Rio Grande Border Environmental Assessment Team, with additional funding support from the El Paso County Water Improvement District No. 1.

  3. Constraints and opportunities for ecological restoration in the Rio Grande Valley, Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are few areas in the United States that have experienced a more precipitous growth than the Lower Rio Grande Valley (RGV) in south Texas, where human populations have almost doubled in the last 20 years. This growth is matched with a rapid proliferation of built environments that is often asso...

  4. Projecting avian responses to landscape management along the Middle Rio Grande, New Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lack of flooding due to river impoundments on the middle Rio Grande has contributed to the spread of exotic vegetation with dense understory fuel loads. Restoration has focused on understory vegetation thinning but it is unclear how these actions impact bird populations. We quantified densities of ...

  5. Estimating water use by giant reed along the Rio Grande River using a large aperture scintillometer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Giant reed (Arundo donax L.) is a bamboo-like perennial invasive weed from Eurasia presenting a severe threat to agroecosystems and riparian areas in Texas and Mexican portions of the Rio Grande River Basin. It is known to consume excessive amounts of water to support its rapid vegetative growth rat...

  6. A survey of bee species found pollinating watermelons in the Lower Rio Grande Valley of Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using a combination of flower traps and visual observations, we surveyed three watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] fields in the Lower Rio Grande Valley to determine what bees inhabit this crop in this region. No managed honey bee (Apis mellifera L.) hives were in any of the fie...

  7. Urban Impact of Dissolved Metals in the Paso del Norte Segment of the Rio Grande

    ERIC Educational Resources Information Center

    Freiwan, Sumayeh Ahmad

    2013-01-01

    The Paso del Norte segment of the Rio Grande experiences two seasons per year; the (wet) irrigation season and the (dry) non-irrigation season. The goal of this study was to improve the understanding of occurrence and contribution of dissolved metals in this region during the non-irrigation season. The objectives of this study were to (1) evaluate…

  8. 76 FR 22075 - Divide Ranger District, Rio Grande National Forest; CO; Black Mesa Vegetation Management Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ...; ] DEPARTMENT OF AGRICULTURE Forest Service Divide Ranger District, Rio Grande National Forest; CO; Black Mesa... Mesa Vegetation Management Project Public Comment. FOR FURTHER INFORMATION CONTACT: Diana McGinn at 719... for Action The purpose and need for the Black Mesa Vegetation Management Project is move...

  9. Projecting avian responses to landscape managment along the middle RIO GRANDE, New Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lack of flooding due to river impoundments on the middle Rio Grande has contributed to the spread of exotic vegetation with dense understory fuel loads. Restoration has focused on understory vegetation thinning but it is unclear how these actions impact bird populations. We quantified densities of ...

  10. Biological Control of Saltcedar and Giant Reed in the Lower Rio Grande Basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Saltcedar (Tamarix spp.) and giant reed (Arundo donax L.) are exotic invasive weeds along the banks of rivers and reservoirs throughout the western U.S. In the Rio Grande Basin of Texas and Mexico, these weeds compete for water resources that are critical for agricultural and urban users and that s...

  11. 40 CFR 81.239 - Upper Rio Grande Valley Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 18 2012-07-01 2012-07-01 false Upper Rio Grande Valley Intrastate Air Quality Control Region. 81.239 Section 81.239 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions §...

  12. 40 CFR 81.83 - Albuquerque-Mid Rio Grande Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false Albuquerque-Mid Rio Grande Intrastate Air Quality Control Region. 81.83 Section 81.83 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions §...

  13. 40 CFR 81.239 - Upper Rio Grande Valley Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Upper Rio Grande Valley Intrastate Air Quality Control Region. 81.239 Section 81.239 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions §...

  14. 40 CFR 81.83 - Albuquerque-Mid Rio Grande Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Albuquerque-Mid Rio Grande Intrastate Air Quality Control Region. 81.83 Section 81.83 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions §...

  15. 40 CFR 81.239 - Upper Rio Grande Valley Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false Upper Rio Grande Valley Intrastate Air Quality Control Region. 81.239 Section 81.239 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions §...

  16. STS-65 Earth observation of dust plumes from Rio Grande in Southern Bolivia

    NASA Technical Reports Server (NTRS)

    1994-01-01

    STS-65 Earth observation taken aboard Columbia, Orbiter Vehicle (OV) 102, is of dust plumes from the Rio Grande in Southern Bolivia. A series of dust plumes can be seen rising from sand banks in the Rio Grande of southern Bolivia, bottom right of this northeast-looking view. The Rio Grande brings sediment from the Andes (foothills visible in the foreground, bottom left) and flows across the flat country of the northern Chaco plain. During the low-flow season, sand banks of this sediment are exposed to northerly winds which often blow dust into the surrounding forest. One of the significances of the dust plumes is that dust acts as a source of nutrient for the local soils. This is the most impressive example of dust ever recorded on Shuttle photography from this river. Such plumes have been seen on photographs from four previous missions (STS-31, STS-47, STS-48, STS-51I) emanating from the Rio Grande. The plumes are regularly space because the sand is blown only from those reaches of th

  17. Environmental Degradation in a Dependent Region: The Rio Grande Valley of Mexico and Texas.

    ERIC Educational Resources Information Center

    Jones, Richard C.

    1999-01-01

    Traces the interrelationships among dependence, environmental degradation, and human health in the Rio Grande Valley of Mexico and Texas. Presents a case study on environmental factors threatening family health in households located on both sides of the border; the health problems can be overcome by addressing restrictive zoning, health services,…

  18. Mapping giant reed along the Rio Grande using airborne and satellite imagery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Giant reed (Arundo donax L.) is a perennial invasive weed that presents a severe threat to agroecosystems and riparian areas in the Texas and Mexican portions of the Rio Grande Basin. The objective of this presentation is to give an overview on the use of aerial photography, airborne multispectral a...

  19. Trace element characteristics of lithospheric and asthenospheric mantle in the Rio Grande rift region

    SciTech Connect

    Perry, F.V.

    1994-06-01

    Trace element analyses of 10 mafic volcanic rocks from the Colorado Plateau transition zone, Colorado Plateau, Rio Grande rift, and Great Plains were obtained to characterize the trace element characteristics of asthenospheric and lithospheric mantle beneath these regions. Characterization of these mantle reservoirs using the trace element contents of basalts allows one to track the response of the lithosphere to continental rifting and extension.

  20. Economic implications for the biological control of Arundo donax: Rio Grande Basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Giant reed, Arundo donax L., is a large bamboo-like plant native to the Mediterranean region. It has invaded several thousand hectares of the Rio Grande riparian habitat in Texas and Mexico. The United States Department of Agriculture-Agricultural Research Service (USDA-ARS) is investigating four ...

  1. Magnetic Investigation of Ancestral Puebloan Rio Grande (New Mexico) Glaze Wares

    NASA Astrophysics Data System (ADS)

    Dyer, J. B.; Geissman, J. W.; Ramenofsky, A. F.

    2007-12-01

    In geologically heterogeneous regions, such as the Rio Grande, archaeologists typically rely on petrographic analyses to determine ceramic provenance and reconstruct prehistoric trade patterns. Even in these regions, other methods are useful for elucidating trade patterns and/or resolving ambiguities from the petrographic data. Magnetic properties of Ancestral central Rio Grande Puebloan ceramics are being acquired to assess their use in identifying provenance, trade patterns, composition, manufacturing techniques, and firing conditions of ceramics, before and during the early European contact period (ca. A.D. 1325-1700) in New Mexico. Similar to the study of Moskowitz et al. (1987), we use a combination of bulk susceptibility, NRM, ARM, and SIRM intensity, AF response by NRM, ARM, and SIRM, thermal demagnetization of NRM and SIRM, and coercivity of remanence, to study temporal change in Rio Grande glaze wares from four archaeological sites in the northern Rio Grande (approximately 90 sherds per site). Rio Grande glaze wares were widely traded among Ancestral Puebloan groups before and during the European contact period. The ceramics are from the two earliest Spanish administrative centers in New Mexico, San Gabriel del Yungue and Palace of the Governors, and two mission pueblos, Pecos Pueblo and San Marcos Pueblo. Magnetic property data are being compared with petrographic observations to test the effectiveness of several magnetic measurements to identify, among other things, ceramic provenance. A tentative observation in our study is that bulk susceptibility values correlate with different ceramic provenances. The mean bulk susceptibility values for Galisteo Basin ceramics, tempered with augite monzonite and hornblende latite, are significantly higher (5.56E-04 and 4.91E-04 SI mass, respectively) than those for Pajarito Plateau ceramics, tempered with glassy tuff, tuff rocks, and andesite, (1.79E-04, 2.53E-04, and 2.58E-04 SI mass, respectively). This study is

  2. Social, political, and institutional setting: Water management problems of the Rio Grande

    USGS Publications Warehouse

    Douglas, A.J.

    2009-01-01

    This paper discusses various water management issues facing federal, state, and local agencies charged with managing the water resources of the Rio Grande River Basin and its major tributaries. The Rio Grande - 3,058 km (=1,900 mi) long - is the fourth longest river in the United States. The river's basin is 870,236 km2 (=336,000 mi2) and for roughly two-thirds of its length it forms the United States-Mexican border. It is a major recreational resource providing world class trout fishing near its headwaters in Colorado's San Juan Mountains and shoreline, angling, and boating opportunities near the Colorado-New Mexico border. The Rio Grande is the principal tourist attraction of Big Bend National Park and flows through downtown Albuquerque and El Paso. Many reaches are wide and broad, but almost all are relatively shallow and not navigable by commercial ships. Nevertheless, it is one of the most important renewable water resources of the southwestern United States and North America. The issue of the "manageability" of the river in the face of social forces and disparate administrative jurisdictions that adversely impact Rio Grande flows is a thread linking various sections of the paper together. The length of the river; the fact that major reaches lie in Colorado, New Mexico, and Texas; and its unique role as an international boundary pose complex management problems. The allocation status quo formed by the complex nexus of existing river laws make it difficult to reshape Rio Grande management. ?? 2009 ASCE.

  3. Cenozoic thermal, mechanical and tectonic evolution of the Rio Grande rift

    NASA Technical Reports Server (NTRS)

    Morgan, P.; Seager, W. R.; Golombek, M. P.

    1986-01-01

    Two areas of New Mexico which exhibit complex but similar Cenozoic histories of extensional tectonism are analyzed. The first study area is the Basin and Range province and southern Rio Gande rift in southern New Mexico; the second study area is the central Rio Grande rift in central and northern New Mexico, the southern San Luis basin, the Espanola basin, and the Albuquerque basin. Two phases of extension were identified: the first phase which began in mid-Oligocene was characterized by local high-strain extension events, low-angle faulting, and the development of broad, shallow basins, all indicating an approximately NE-SW + or - 25 deg extension direction; the later phase which occurred primarily in the late Miocene, was characterized by synchronous, high-angle faulting, resulting in large vertical strains which produced the modern Rio Grande rift morphology. Extension direction was approximately E-W. Geotherms were estimated and lithospheric strength curves were calculated for these two phases of extension. A high geotherm was deduced for the early phase resulting in a shallow crustal brittle transition, and insignificant mantle strength. The lithosphere subsequently cooled, resulting in a significant zone of mantle strength beneath the Moho. It is concluded that the interrelationship among regional and local prerifting, synrifting, and postrifting events in the Rio Grande rift attests to the fact that the rifting (in the region studied) should be considered in the context of other geologic events.

  4. Tectonic rotations within the Rio Grande rift - Evidence from paleomagnetic studies

    NASA Technical Reports Server (NTRS)

    Brown, L. L.; Golombek, M. P.

    1985-01-01

    Paleomagnetic studies on Miocene Pliocene volcanic rocks from the Espanola basin of the Rio Grande rift, New Mexico, reveal directions discordant form the expected mean direction for North America. The Paliza Canyon Formation, Tschicoma Formation, and Lobato Basalt, all sampled in the Jemez Mountains west of the Pajarito fault zone, have mean declinations east of the expected mean. The Cerros del Rio volcanics, lying east of the Pajarito fault zone, have a westerly declination. Combined with published data on the Santa Fe Group sediments east of the fault zone, and the Valles Rhyolite, west of the fault zone, distinct rotations of the two areas are evident. The western block has rotated clockwise 12 deg, while the eastern block shows 16 deg of conter-clockwise motion. Differential rotations of 25-30 deg are calculated between the two blocks; 4 deg/m.y. is the minimum differential rotation for the past 5 m.y. Geologic explanations for these rotations include the opening of the Rio Grande rift in response to clockwise rotation of the Colorado Plateau and significant left slip along the Rio Grande rift.

  5. Quantifying Ichthyofaunal Zonation and Species Richness along a 2800 km Reach of the Rio Chama and Rio Grande (U.S.A.)

    EPA Science Inventory

    Ichthyofaunal zonation occurs when lotic fishes are partitioned into distinct assemblages, usually in response to longitudinally distributed habitats. Several studies have documented zonation within the Rio Grande, but this is the first to quantitatively test the zonation hypothe...

  6. A regional perspective on arsenic in waters of the Middle Rio Grande Basin, New Mexico

    SciTech Connect

    Chapin, C.E.; Dunbar, N.W.

    1995-12-31

    The objectives of this paper are to provide a concise summary and a regional perspective on the geochemical characteristics and occurrence of arsenic in waters of the Middle Rio Grande Basin. The initial intent was to discuss arsenic in groundwater, but, because of interrelationships between ground and surface waters, the need to research arsenic variations in both soon became apparent. To develop a regional perspective on natural variations in arsenic in ground and surface waters of the western US the author obtained all the arsenic analyses in the STORET data base of the US Environmental Improvement Agency for the Rio grande, Colorado and Snake rivers, and a more limited data set for some of their tributaries, some wastewater treatment plants along their drainages, and for some springs and wells.

  7. Geohydrology of White Rock Canyon of the Rio Grande from Otowi to Frijoles Canyon

    SciTech Connect

    Purtymun, W.D.; Peters, R.J.; Owens, J.W.

    1980-12-01

    Twenty-seven springs discharge from the Totavi Lentil and Tesuque Formation in White Rock Canyon. Water generally acquires its chemical characteristics from rock units that comprise the spring aquifer. Twenty-two of the springs are separated into three groups of similar aquifer-related chemical quality. The five remaining springs make up a fourth group with a chemical quality that differs due to localized conditions in the aquifer. Localized conditions may be related to recharge or discharge in or near basalt intrusion or through faults. Streams from Pajarito, Ancho, and Frijoles Canyons discharge into the Rio Grande in White Rock Canyon. The base flow in the streams is from springs. Sanitary effluent in Mortandad Canyon from the treatment plant at White Rock also reaches the Rio Grande.

  8. Economic impact of alternative policy responses to prolonged and severe drought in the Rio Grande Basin

    NASA Astrophysics Data System (ADS)

    Booker, James F.; Michelsen, Ari M.; Ward, Frank A.

    2005-02-01

    In the Rio Grande Basin, water is overallocated, demands are growing, and river flows and uses are vulnerable to drought and climate change. Currently, the basin is in the third year of severe drought; irrigation and municipal water diversions have been severely curtailed; extensive diversions threaten endangered species, and reservoir volumes are nearly depleted. A central challenge is development of policies that efficiently and equitably allocate the basin's water resources among competing uses across political and institutional jurisdictions. A basin-wide, nonlinear programming model optimizes resource allocations and water use levels for the upper part of the Rio Grande Basin to test whether institutional adjustments can reduce damages caused by drought. Compared to existing institutions, we find that future drought damages could be reduced by 20 and 33% per year through intracompact and interstate water markets, respectively, that would allow water transfers across water management jurisdictions. Results reveal economic tradeoffs among water uses, regions, and drought control strategies.

  9. Lower Rio Grande Valley transboundary air pollution project (TAPP). Project report 1996--1997

    SciTech Connect

    Mukerjee, S.; Shadwick, D.S.; Dean, K.E.; Carmichael, L.Y.; Bowser, J.J.

    1999-04-01

    The Lower Rio Grande Valley Transboundary Air Pollution Project (TAPP) was a US-Mexico Border XXI project to find out if air pollutants were moving across the border from Mexico into the Lower Rio Grande Valley of Texas and to see what levels of air pollutants were present. Ambient measurements and meteorology were collected data for a year (March 1996-March 1997) at three fixed sites in and near Brownsville, Texas very close to the US-Mexico border on a continuous and 24-h internal basis. Overall levels of air pollution were similar to or lower than other areas in Texas and elsewhere. Based on wind sector analyses, transport of air pollution across the border did not appear to adversely impact air quality on the US side of the Valley. Southeasterly winds from the Gulf of Mexico were largely responsible for the clean air conditions.

  10. RiSA: A Science Festival for the Bilingual and Bicultural Rio Grande Valley

    NASA Astrophysics Data System (ADS)

    Key, Joey Shapiro; Torres, Cristina; Stone, Robert

    2014-03-01

    The Rio Grande Science and Arts (RiSA) Festival organized by the Center for Gravitational Wave Astronomy (CGWA) at the University of Texas at Brownsville (UTB) will use a wide variety of artforms to bring physics and science topics to the bilingual and bicultural population of the Rio Grande Valley of South Texas. The science and art faculty at UTB will partner with art and education professionals to create an annual community event celebrating science though art. Music, dance, poetry, and visual arts will headline the festival activities. Festival events and products will be produced in both English and Spanish to attract and inform the bilingual local community. The RiSA Festival is supported by the Science Festival Alliance and the Sloan Foundation. Supported by the Science Festival Alliance and the Sloan Foundation.

  11. Rhipicephalus sanguineus (ACARI: IXODIDAE) BITING A HUMAN BEING IN PORTOALEGRE CITY, RIO GRANDE DO SUL, BRAZIL

    PubMed Central

    MENTZ, Márcia Bohrer; TROMBKA, Marcelo; da SILVA, Guilherme Liberato; SILVA, Carlos Eugênio

    2016-01-01

    We report the finding of a female brown dog tick, Rhipicephalus sanguineus (Acari: Ixodidae) on the scalp of a male patient in Porto Alegre, Rio Grande do Sul, Brazil. Human parasitism by this tick is rare and has seldomly been reported in the literature, despite its recognized importance since it can act as a vector of Rickettsia rickettsii, the agent of spotted fever. PMID:27074329

  12. Poverty and Problems of Development in the Lower Rio Grande Valley of Texas.

    ERIC Educational Resources Information Center

    Miller, Michael V.

    Bounded on the west and south by Mexico and to the east by the Gulf, the Lower Rio Grande Valley of Texas is separated from the nearest U.S. urban center of any size by miles of flat and arid brushland. Its total population of approximately 335,000 is essentially composed of 2 groups--Mexican Americans and Anglos. Although the region is one of the…

  13. Finite element analysis of the I-40 bridge over the Rio Grande

    SciTech Connect

    Farrar, C.R.; Duffey, T.A.; Goldman, P.A.; Jauregui, D.V.; Vigil, J.S.

    1996-01-01

    In the 1960s and 1970s numerous bridges were built in the US with a design similar to those on Interstate 40 (I-40) over the Rio Grande in Albuquerque, New Mexico. The Federal Highway Administration (FHWA) and the National Science Foundation (NSF) have provided funds to New Mexico State University (NMSU) through the New Mexico State Highway and Transportation Department (NMSH and TD) and The Alliance For Transportation Research (ATR) for evaluation and testing of the existing fracture-critical bridges over the Rio Grande. Because the I-40 Bridges over the Rio Grande were to be razed during the summer of 1993, the investigators were able to introduce damage into the structure in order to test various damage identification methods and to observe the changes in load paths through the structure caused by the cracking. To support this research effort, NMSU contracted Los Alamos National Laboratory (LANL) to perform experimental modal analyses, and to develop experimentally verified numerical models of the bridge. A previous report (LA-12767-MS) summarizes the results of the experimental modal analyses. This report summarizes the numerical analyses of the bridges and compares the results of these analyses to the experimental results.

  14. DIETARY CHARACTERIZATIONS IN A STUDY OF HUMAN EXPOSURES IN THE LOWER RIO GRANDE VALLEY: I. FOODS AND BEVERAGES

    EPA Science Inventory

    The Lower Rio Grande Valley Environmental Study (LRGVES), a cooperative effort between various federal and state agencies, responded to concerns of the local community about possible adverse health effects related to environmental conditions. The LRGVES pilot project, conducted d...

  15. The potential to improve water quality in the middle Rio Grande through effective wetland restoration.

    PubMed

    Rodriguez, Ruth; Lougheed, Vanessa L

    2010-01-01

    The Rio Grande, which forms the United States-Mexico border for much of its course, receives diverse pollutants from both urban and agricultural areas, most notably in the sister cities of El Paso (TX, USA)-Ciudad Juárez (CHI, Mexico). This study aimed to describe regional trends in water quality in waters near the El Paso-Ciudad Juárez metroplex and to examine the potential for water quality improvement through the use of a created wetland. Very few differences in nutrient chemistry were found among drains, canals and the Rio Grande, with the exception of elevated chloride and lower phosphorus levels found in the drains. Overall, chloride concentrations increased with distance downstream, likely due to concentration of salts via evaporation from irrigated agriculture. A wastewater treatment plant (WWTP) contributed substantially to total phosphorus and nitrate levels, which, together with ammonia, tended to exceed state criteria for water quality downstream of the WWTP outflow. The created Rio Bosque wetlands reduced nitrate concentrations in the water, possibly via denitrification enhanced by algae; algae increased in biomass as water flowed through the wetlands. However, the diversion of water for irrigated agriculture, resulting in the absence of water, and thus aquatic plants, in the wetland in the summer has limited the ability of this wetland to improve regional water quality. PMID:20705996

  16. Ground-Water Resource Assessment in the Rio Grande de Manati Alluvial Plain, Rio Arriba Saliente Area, Puerto Rico

    USGS Publications Warehouse

    Torres-Gonzalez, Sigfredo; Gómez-Gómez, Fernando; Warne, Andrew G.

    2002-01-01

    The alluvial aquifer within a 160-acre area of the Rio Grande de Manati alluvial plain was investigated to evaluate its potential as a water-supply source for the Barrios Rio Arriba Saliente and Pugnado Afuera, municipio of Manati, Puerto Rico. Analysis of well boring samples and the results of electric resistivity surveys indicate that the average thickness of the unconsolidated alluvial deposits in the study area is about 100 to 110 feet. The alluvium is a mixture of sand and gravel, which generally has a porosity of 0.2 to 0.35. Short-duration pump tests in small-diameter piezometers indicate that the alluvial aquifer has a hydraulic conductivity of about 200 feet per day and a transmissivity of about 7,900 feet squared per day. Analyses of water levels in piezometers, combined with stage measurements at a series of surveyed reference points along the Rio Grande de Manati channel, indicate that the water-table gradient in the alluvial aquifer is about 0.001, and that ground-water flow is generally from south to north, in the general direction of river flow. The water-table data indicate that the Rio Grande de Manati is the principal source of ground-water recharge to the alluvial aquifer in the study area. Because base flow for the Rio Grande de Manati is usually greater than 44 cubic feet per second, a continuous withdrawal rate of 0.5 to 1.0 cubic foot per second (225 to 450 gallons per minute) from a production well is possible. Chemical analysis of a ground-water sample indicates that the alluvial aquifer water meets U.S. Environmental Protection Agency secondary standards for selected constituents. Bacteriological analysis of ground-water samples indicates that the ground water contains little or no fecal coliform or fecal streptococcus bacteria. Although long-term data from upstream of the study area indicate high levels of fecal coliform and fecal streptococcus prior to 1996, bacteriological analyses of Rio Grande de Manati water samples obtained during

  17. Evaluating Mantle-to-Surface Hydrologic Connections in the Rio Grande Rift using Mathematical Modeling

    NASA Astrophysics Data System (ADS)

    Woolsey, E. E.; Person, M. A.; Crossey, L. J.; Phillips, F. M.; Karlstrom, K. E.; Williams, A. J.

    2012-12-01

    The southern terminus of the Albuquerque Basin along the Rio Grande Rift (RGR) is characterized by high river salinity (200-700 mg/L), temperature (29°C at 155 m depth), and mantle helium (0.26-0.37 RC/A) anomalies, which are clear indications of complex mixing of mantle and crustal fluids. The zone of maximum uplift of the Socorro Magma Body (SMB) is also localized at the southern end of the Albuquerque Basin. Two end member hypotheses have been proposed to account for salt loading in the Rio Grande: 1) basin constriction forcing brines and warm water to the surface and 2) fault-controlled fluid flow from deep mantle/magmatic sources. A better understanding of the hydrologic controls is necessary to assess the degradation of water quality along the Rio Grande. The role of basin constriction and fault-controlled fluid flow in explaining observed fluxes of salinity, enthalpy and primordial helium is examined in this study using mathematical modeling. A basin-scale, cross-sectional hydrologic model was constructed along the RGR in the Albuquerque and Socorro Basins drawn to a depth of 19 km to incorporate deeply derived inputs related to the SMB. The finite element model used is capable of representing heat, brine and noble gas transport. Geologic maps, well bore lithologic logs, as well as gravity and seismic-surveys were used to construct the general N-S cross-section on which the model is based. The model follows the longitudinal profile of the Rio Grande through the Albuquerque Basin and into the Socorro Basin. Multiple versions of the model were created based on two working hypotheses to better understand the structural and hydrologic controls at the basin boundary. One model assumes that the Tertiary dike exposed at the boundary acts as a conduit for deeply sourced fluids and primordial 3He related to the SMB. An alternate version assumes all the units down to the Precambrian basement rock decrease in depth significantly at the basin boundary due to the

  18. Effects of reservoir installation, San Juan-Chama Project water, and reservoir operations on streamflow and water quality in the Rio Chama and Rio Grande, northern and central New Mexico, 1938-2000

    USGS Publications Warehouse

    Langman, Jeff B.; Anderholm, Scott K.

    2004-01-01

    The coordinated operation of Heron, El Vado, and Abiquiu Dams on the Rio Chama and Cochiti Dam on the Rio Grande and the importation of Colorado River Basin water by the San Juan-Chama Project have altered streamflow and water quality of the Rio Chama and Rio Grande in northern and central New Mexico. The coordinated retention of streamflow in the four reservoirs increased median streamflows, decreased extreme flows, and decreased periods of small streamflow; inflow of San Juan-Chama Project water increased overall streamflow in the Rio Chama and Rio Grande. These changes to streamflow decreased specific conductance and suspended-sediment concentration and increased pH in the Rio Chama and the Rio Grande. Following construction of Heron and Cochiti Dams and integration of reservoir operations on the Rio Chama and the Rio Grande, the inflow of San Juan-Chama Project water and retention of snowmelt runoff influenced water quality. These influences varied by season because reservoir releases fluctuated according to downstream user needs and annual streamflow variation. The influences of San Juan-Chama Project water and retained snowmelt on water quality diminished with downstream flow as the Rio Grande was subjected to various natural and anthropogenic inflows. Because of the variability and type of seasonal influences, streamflow did not have a strong annual correlation with water quality in the Rio Chama or the Rio Grande.

  19. Distribution and habitat associations of juvenile Common Snook in the lower Rio Grande, Texas

    USGS Publications Warehouse

    Huber, Caleb G.; Grabowski, Timothy B.; Patino, Reynaldo; Pope, Kevin L.

    2014-01-01

    Common Snook Centropomus undecimalis were once abundant off the Texas coast, but these populations are now characterized by low abundance and erratic recruitment. Most research concerning Common Snook in North America has been conducted in Florida and very little is known about the specific biology and habitat needs of Common Snook in Texas. The primary objective of this study was to describe the habitat use patterns of juvenile Common Snook and their role in the fish assemblage in the lower portion of the Rio Grande, Texas. Secondarily, we documented the relationship between age and juvenile reproductive development. Fish were collected during January–March 2006 from the lower 51.5 km of the Rio Grande using a bottom trawl and boat-mounted electrofisher. Measurements of water quality and other habitat traits were recorded at each sampling site. We captured 225 Common Snook exclusively in freshwater habitats above river kilometer 12.9. The distribution of juvenile Common Snook was not random, but influenced primarily by turbidity and dissolved oxygen. Sex differentiation and gonadal development based on histological examination of gonads established that age-1 and age-2 Common Snook were juvenile, prepubertal males. There was no difference between the age groups in their overall distribution in the river. However, age-2 Common Snook were associated with deeper areas with faster currents, higher conductivity, and steeper banks. Overall, Common Snook in the lower Rio Grande show substantial differences in habitat use than their counterparts in other parts of the range of the species, but it is unclear whether this is due to differences in habitat availability, behavioral plasticity, or some combination thereof.

  20. Late Pleistocene landslide-dammed lakes along the Rio Grande, White Rock Canyon, New Mexico

    SciTech Connect

    Reneau, S.L.; Dethier, D.P.

    1996-11-01

    Massive slump complexes composed of Pliocene basaltic rocks and underlying Miocene and Pliocene sediments flank the Rio Grande along 16 km of northern White Rock Canyon, New Mexico. The toe area of at least one slump complex was active in the late Pleistocene, damming the Rio Grande at least four times during the period from 18 to 12 {sup 14}C ka and impounding lakes that extended 10-20 km upriver. Stratigraphic relationships and radiocarbon age constraints indicate that three separate lakes formed between 13.7 and 12.4 {sup 14}C ka. The age and dimensions of the ca. 12.4 ka lake are best constrained; it had an estimated maximum depth of {approx}30 m, a length of {approx}13 km, a surface area of {approx}2.7 km{sup 2}, and an initial volume of {approx}2.5 x 10{sup 7} m{sup 3}. The youngest landslide-dammed lakes formed during a period of significantly wetter regional climate, strongly suggesting that climate changes were responsible for reactivation of the slump complexes. We are not certain about the exact triggering mechanisms for these landslides, but they probably involved removal of lateral support due to erosion of the slope base by the Rio Grande during periods of exceptionally high flood discharge or rapid incision; increased pore pressures associated with higher water tables; higher seepage forces at sites of ground-water discharge; or some combination of these processes. Seismic shaking could also have contributed to triggering of some of the landslides, particularly if aided by wet antecedent conditions. 54 refs., 19 figs., 3 tabs.

  1. HOSPITALIZATIONS FOR CHOLECYSTITIS AND CHOLELITHIASIS IN THE STATE OF RIO GRANDE DO SUL, BRAZIL

    PubMed Central

    NUNES, Emeline Caldana; ROSA, Roger dos Santos; BORDIN, Ronaldo

    2016-01-01

    ABSTRACT Background: The cholelithiasis is disease of surgical resolution with about 60,000 hospitalizations per year in the Sistema Único de Saúde (SUS - Brazilian National Health System) of the Rio Grande do Sul state. Aim: To describe the profile of hospitalizations for cholecystitis and cholelithiasis performed by the SUS of Rio Grande do Sul state, 2011-2013. Methods: Hospital Information System data from the National Health System through morbidity list for cholelithiasis and cholecystitis (ICD-10 K80-K81). Variables studied were sex, age, number of hospitalizations and approved Hospitalization Authorizations (AIH), total amount and value of hospital services generated, days and average length of stay, mortality, mortality and case fatality ratio, from health regions of the Rio Grande do Sul. Results: During 2011-2013 there were 60,517 hospitalizations for cholecystitis and cholelithiasis, representing 18.86 hospitalizations per 10,000 inhabitants/year, most often in the age group from 60 to 69 years (41.34 admissions per 10,000 inhabitants/year) and female (27.72 hospitalizations per 10,000 inhabitants/year). The fatality rate presented an inverse characteristic: 13.52 deaths per 1,000 admissions/year for males, compared with 7.12 deaths per 1,000 admissions/year in females. The state had an average total amount spent and value of hospital services of R$ 16,244,050.60 and R$ 10,890,461.31, respectively. The health region "Capital/Gravataí Valley" exhibit the highest total expenditure and hospital services, and the largest number of deaths, and average length of stay. Conclusion: The hospitalization and lethality coefficients, the deaths, the length of stay and spending related to admissions increased from 50 years old. Females had a higher frequency and higher values ​​spent on hospitalization, while the male higher coefficient of mortality and mean hospital stay. PMID:27438030

  2. Dynamic characterization and damage detection in the I-40 bridge over the Rio Grande

    SciTech Connect

    Farrar, C.R.; Baker, W.E.; Bell, T.M.; Cone, K.M.; Darling, T.W.; Duffey, T.A.; Eklund, A.; Migliori, A.

    1994-06-01

    In the 1960`s and 1970`s over 2500 bridges were built in the U.S. with a design similar to those on Interstate 40 over the Rio Grande in Albuquerque, New Mexico. These bridges were built without structural redundancy and typically have only two plate girders carrying the entire dead and live loads. Failure of either girder is assumed to produce catastrophic failure of the bridge, hence these bridges are referred to as fracture-critical bridges. The Federal Highway Administration (FHWA) and the National Science Foundation (NSF) have provided funds to New Mexico State University (NMSU) through the New Mexico State Highway and Transportation Department (NMSH&TD) and The Alliance For Transportation Research (ATR) for evaluation and testing of the existing fracture critical bridges over the Rio Grande. Because the 1-40 bridges over the Rio Grande were to be razed during the summer of 1993, the investigators were able to introduce simulated fatigue cracks, similar to those observed in the field, into the structure in order to test various damage identification methods and to observe the changes in load paths through the structure caused by the cracking. To support this research effort, NMSU contracted Los Alamos National Laboratory (LANL) to perform experimental modal analyses, and to develop experimentally verified numerical models of the bridge. Scientists from the LANL`s Condensed Matter and Thermal Physics Group (P-10) applied state-of-the-art sensors and data acquisition software to the modal tests. Engineers from the LANL`s Advanced Engineering Technology Group (MEE-13) conducted ambient and forced vibration tests to verify detailed and simplified finite element models of the bridge. Forced vibration testing was done in conjunction with engineers from Sandia National Laboratory (SNL) who provided and operated a hydraulic shaker.

  3. The topographic distribution of annual incoming solar radiation in the Rio Grande River Basin

    NASA Astrophysics Data System (ADS)

    Dubayah, R.; van Katwijk, V.

    1992-11-01

    We model the annual incoming solar radiation topoclimatology for the Rio Grande River basin in Colorado, U.S.A. Hourly pyranometer measurements are combined with satellite reflectance data and 30 m digital elevation models within a topographic solar radiation algorithm. Our results show that there is large spatial variability within the basin, even at an annual integration length, but the annual, basin-Wide mean is close to that measured by the pyranometers. The variance within 16 km2 and 100 km2 regions is a linear function of the average slope in the region, suggesting a possible parameterization for sub-grid cell variability.

  4. The topographic distribution of annual incoming solar radiation in the Rio Grande River basin

    SciTech Connect

    Dubayah, R.; Van Katwijk, V. USDA, Hydrology Lab., Beltsville, MD )

    1992-11-01

    We model the annual incoming solar radiation topoclimatology for the Rio Grande River basin in Colorado, U.S.A. Hourly pyranometer measurements are combined with satellite reflectance data and 30-m digital elevation models within a topographic solar radiation algorithm. Our results show that there is large spatial variability within the basin, even at an annual integration length, but the annual, basin-wide mean is close to that measured by the pyranometers. The variance within 16 sq km and 100 sq km regions is a linear function of the average slope in the region, suggesting a possible parameterization for sub-grid-cell variability. 13 refs.

  5. The topographic distribution of annual incoming solar radiation in the Rio Grande River basin

    NASA Technical Reports Server (NTRS)

    Dubayah, R.; Van Katwijk, V.

    1992-01-01

    We model the annual incoming solar radiation topoclimatology for the Rio Grande River basin in Colorado, U.S.A. Hourly pyranometer measurements are combined with satellite reflectance data and 30-m digital elevation models within a topographic solar radiation algorithm. Our results show that there is large spatial variability within the basin, even at an annual integration length, but the annual, basin-wide mean is close to that measured by the pyranometers. The variance within 16 sq km and 100 sq km regions is a linear function of the average slope in the region, suggesting a possible parameterization for sub-grid-cell variability.

  6. Radionuclide concentrations in bed sediment and fish tissue within the Rio Grande drainage basin

    SciTech Connect

    Booher, J.L.; Fresquez, P.R.; Carter, L.F.; Gallaher, B.M.; Mullen, M.A.

    1998-02-01

    In 1992-93, Los Alamos National Laboratory collaborated with the U.S. Geological Survey in an effort to characterize radionuclide concentrations in bed sediment and fish tissue within the Rio Grande drainage basin from Colorado to Texas. Bed sediment was sampled from 18 locations for cesium ({sup 137}Cs), tritium ({sup 3}H), strontium ({sup 90}Sr), plutonium ({sup 238}Pu and {sup 239}Pu), americium ({sup 241}Am), total uranium ({sup tot}U) and alpha, beta, and gamma activity. Fish tissue was sampled from 12 locations for {sup 137}Cs, {sup 90}Sr, {sup 238}Pu, {sup 239}Pu and {sup tot}U.

  7. [Violence and social distress among transgender persons in Santa Maria, Rio Grande do Sul State, Brazil].

    PubMed

    Souza, Martha Helena Teixeira de; Malvasi, Paulo; Signorelli, Marcos Claudio; Pereira, Pedro Paulo Gomes

    2015-04-01

    The authors conducted an ethnographic research with transgender persons in Santa Maria, Rio Grande do Sul State, Brazil, in 2012, using participant observation, semi-structured interviews, and following their everyday lives. These individuals invariably experienced physical and symbolic violence and the resulting distress, a condition they had to deal with in their careers and daily practices and tasks. The article discusses the violence experienced by transvestites (in the family, school, police precincts, and health services), specifically seeking to understand how such violence relates to their experiences with health services and how the latter respond. PMID:25945986

  8. Water resources simulation in the Rio Grande basin using coupled models

    SciTech Connect

    Springer, E.P.; Winter, C.L.; Bossert, J.E.

    1999-04-01

    Regional assessments of water resources under global climate change require models that can resolve management, land use, and climate effects. Los Alamos National Laboratory is developing a coupled model of water resources that places a river basin in its global context. The upper Rio Grande basin above El Paso, Texas is the testbed for this model. The model structure and computational approach are emphasize and issues such as nonlinear feedback between components and spatial and temporal scaling of processes are discussed. Using simulations of regional meteorology, the effects of high spatial resolution simulations on the distribution of precipitation are demonstrated.

  9. Historic interrelationships of humans and the ecosystems of the Middle Rio Grande Basin

    SciTech Connect

    Scurlock, D.

    1995-12-31

    An ongoing study of the environmental history of the Middle Rio Grande Basin, New Mexico, is revealing major impacts on and changes to ecosystems over the past 455 years. Various land uses, such as grazing, irrigation farming, logging, and constructing flood control features, combined with climatic fluctuations have adversely produced changes in stream flow-morphology, ground water levels, topsoils, biotic communities, and individual species. Indigenous human populations have been adversely impacted by these modifications as well. Continued land-water use-impacts from a rapidly increasing regional population portend continuing changes and major challenges for natural and human resource management agencies and organizations.

  10. Historical changes in streamflows, channel morphology, and riparian vegetation of the Rio Grande downstream of Brownsville, Texas

    USGS Publications Warehouse

    Moring, J. Bruce; Setser, Rita

    2000-01-01

    The Rio GrandefRio Bravo drains an area of more than 440,300 square kilometers of Mexico and southwestern United States (Bartlett. 1984). The Rio Grande flows for 3,000 kilometers from its headwaters in the San Juan Mountains of southern Colorado to the Gulf of Mexico downstream of Brownsville, Texas. The "Rio," as it is often called, drains the southern Rocky Mountains of Colorado and northern New Mexico; the vast Chihuahuan Desert of southern New Mexico, northern Mexico, and southwestern Texas; ami the subtropical lower valley of southern Texas (fig. I).

  11. Evaluation of MODIS snow cover products in the Upper Rio Grande River Basin

    NASA Astrophysics Data System (ADS)

    Klein, A.; Barnett, A.; Lee, S.

    2003-04-01

    Snow cover is an important water resource for the Upper Rio Grande River Basin of Colorado and New Mexico. Global daily snow cover maps currently are produced from Moderate Resolution Imaging Spectroradiometer (MODIS) data and are freely distributed by the National Snow and Ice Data Center (NSIDC). The classification accuracy of these daily snow maps was assessed by comparing MODIS snow cover maps with operational snow cover maps produced by the National Operational Hydrologic Remote Sensing Center (NOHRSC) and against in situ SNOTEL (Snowpack Telemetry) measurements for the 2000-2001 snow season. For days during the 2000-2001 snow season where both MODIS and NOHRSC snow maps exist the overall snow classification agreement is 86 percent. Comparisons of both snow maps against in situ SNOTEL measurements for the same days indicate snow mapping accuracies of 94 percent and 76 percent for MODIS and NOHRSC, respectively. A lengthened comparison of MODIS against SNOTEL measurements which increases the number of comparisons for snow-free conditions indicates a slightly lower overall classification accuracy of 88 percent. In addition, assessment of the usefulness of these two snow cover products as inputs into the Snowmelt Runoff Model (SRM) for streamflow prediction in the Upper Rio Grande River Basin is ongoing.

  12. A Coupled Modeling System to Simulate Water Resources in the Rio Grande Basin

    SciTech Connect

    Bossert, J.E.; Breshears, D.D.; Campbell, K.; Costigan, K.R.; Greene, R.K.; Keating, E.H.; Kleifgen, L.M.; Langley, D.L.; Martens, S.N.; Sanderson, J.G.; Springer, E.P.; Stalker, J.R.; Tartakovsky, D.M.; Winter, C.L.; Zyvoloski, G.A.

    1999-01-11

    Limited availability of fresh water in arid and semi-arid regions of the world requires prudent management strategies from accurate, science-based assessments. These assessments demand a thorough understanding of the hydrologic cycle over long time periods within the individual water-sheds that comprise large river basins. Measurement and simulation of the hydrologic cycle is a tremendous challenge, involving a coupling between global to regional-scale atmospheric precipitation processes with regional to local-scale land surface and subsurface water transport. Los Alamos National Laboratory is developing a detailed modeling system of the hydrologic cycle and applying this tool at high resolution to assess the water balance within the upper Rio Grande river basin. The Rio Grande is a prime example of a river system in a semiarid environment, with a high demand from agricultural, industrial, recreational, and municipal interests for its water supply. Within this river basin, groundwater supplies often augment surface water. With increasing growth projected throughout the river basin, however, these multiple water users have the potential to significantly deplete groundwater resources, thereby increasing the dependence on surface water resources.

  13. Changes on the fine sediment dynamics after the Port of Rio Grande expansion

    NASA Astrophysics Data System (ADS)

    Silva, P. D.; Lisboa, P. V.; Fernandes, E. H.

    2015-01-01

    The Patos Lagoon estuary is a reservoir of fine sediments derived from the continental basin, which is exported to the coastal area through a narrow channel with average discharge of 2000 m3 s-1. The Port of Rio Grande is located in this connection channel between the Patos Lagoon and the Atlantic Ocean, and recently received investments from the Brazilian Government to expand its draft and modify the configuration of the breakwaters located at the mouth. The objective of this study is to investigate changes in the fine sediment dynamics in the estuarine and coastal region, after the modernization work carried out at the Port of Rio Grande. The study was conducted using a three-dimensional numerical model (TELEMAC-3D) coupled with a sediment in suspension and morphological model (SediMorph). Results were analyzed in a comparative way in relation to the deposition pattern observed in these regions before and after the construction work. Results indicate that there was a change in the deposition pattern and redistribution of sediment at the bottom due to hydrodynamic changes resulting from the new configuration of the breakwaters and progressive deepening of the access channel.

  14. Genetic diversity of Brucella ovis isolates from Rio Grande do Sul, Brazil, by MLVA16

    PubMed Central

    2014-01-01

    Background Ovine epididymitis is predominantly associated with Brucella ovis infection. Molecular characterization of Brucella spp. achieved by multi-locus variable number of tandem repeats (VNTR) analyses (MLVA) have proved to be a powerful tool for epidemiological trace-back studies. Thus, the aim of this study was to evaluate the genetic diversity of Brucella ovis isolates from Rio Grande do Sul State, Brazil, by MLVA16. Findings MLVA16 genotyping identified thirteen distinct genotypes and a Hunter-Gaston diversity index of 0.989 among the fourteen B. ovis genotyped strains. All B. ovis MLVA16 genotypes observed in the present study represented non-previously described profiles. Analyses of the eight conserved loci included in panel 1 (MLVA8) showed three different genotypes, two new and one already described for B. ovis isolates. Among ten B. ovis isolates from same herd only two strains had identical pattern, whereas the four isolates with no epidemiologic information exhibited a single MLVA16 pattern each. Analysis of minimal spanning tree, constructed using the fourteen B. ovis strains typed in this study together with all nineteen B. ovis MLVA16 genotypes available in the MLVAbank 2014, revealed the existence of two clearly distinct major clonal complexes. Conclusions In conclusion, the results of the present study showed a high genetic diversity among B. ovis field isolates from Rio Grande do Sul State, Brazil, by MLVA16. PMID:25015223

  15. Paracoccidioidomycosis in southern Rio Grande do Sul: A retrospective study of histopathologically diagnosed cases

    PubMed Central

    de Souza, Silvana Pereira; Jorge, Valéria Magalhães; Xavier, Melissa Orzechowski

    2014-01-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis caused by the fungus Paracoccidioides brasiliensis and is endemic to Brazil. The aim of this study was to perform a retrospective analysis of the PCM cases in the countryside south of Rio Grande do Sul, Brazil. The files from four histopathology laboratories located in the city of Pelotas were obtained, and all of the epidemiological and clinical data from the PCM diagnosed cases were collected for analysis. A total of 123 PCM cases diagnosed between 1966 and 2009 were selected. Of these patients, 104 (84.5%) were male, and 17 were female. The patients ranged from 02 to 92 years of age. Fifty-two cases (41.9%) were obtained from the oral pathology laboratory, and the remaining 71 cases (58.1%) were obtained from the three general pathology laboratories. Of all of the patients studied, 65.2% lived in rural zones and worked in agriculture or other related fields. Data on the evolution of this disease was available for 43 cases, and the time frame ranged from 20 to 2920 days (mean = 572.3 days). An accurate diagnosis performed in less than 30 days only occurred in 21% of the cases. PCM is endemic to the countryside of Rio Grande do Sul. Therefore, it is recommended that PCM be included as a differential diagnosis, mainly for individuals between 30 and 60 years of age, living in rural zones and who have respiratory signs and associated-oropharyngeal lesions. PMID:24948940

  16. Seroepidemiology of Paracoccidioides brasiliensis infection in horses from Rio Grande do Sul, Brazil.

    PubMed

    Albano, Ana Paula Neuschrank; Klafke, Gabriel Baracy; Brandolt, Tchana Martinez; Da Hora, Vanusa Pousada; Nogueira, Carlos Eduardo Wayne; Xavier, Melissa Orzechowski; Meireles, Mário Carlos Araújo

    2015-06-01

    Paracoccidioides brasiliensis is the etiological agent of the major systemic mycosis in Brazil, called paracoccidioidomycosis. Although the Rio Grande do Sul is considered an endemic area of the disease, there are few studies on the ecology of P. brasiliensis in the state. Therefore, this study aimed to evaluate the infection of P. brasiliensis in horses from the mesoregion of Southwest Riograndense, using these animals as sentinels. Serological techniques, such as double immunodiffusion in agar gel (AGID) and indirect ELISA, were performed to detect the anti-gp43 P. brasiliensis antibody in horses from five different farms in the region of Bagé, RS, Brazil. Serology was performed in 200 Pure Blood English horses up to two years of age that were born and raised exclusively at the farms. Of these horses, 12% had anti-gp43 antibodies according to the ELISA results, with rates ranging from 0 to 30% according to the farm of origin (p < 0.001). Based on the immunodiffusion results, all equine serum samples were negative. These results indicate the presence of the fungus P. brasiliensis in the middle region of the southwestern state of Rio Grande do Sul, Brazil. PMID:26273267

  17. [Faunistic analysis of leafhopper (Hemiptera: Cicadellidae) species in vineyards of Rio Grande do Sul State, Brazil].

    PubMed

    Ringenberg, Rudiney; Lopes, João R S; Botton, Marcos; Azevedo-Filho, Wilson S De; Cavichioli, Rodney R

    2010-01-01

    In some American countries, grapevines are affected by Pierce's disease (PD), which is caused by a particular strain of Xylella fastidiosa not yet reported in Brazil. In order to investigate the potential for PD spread in Brazil in case of pathogen introduction, we conducted a faunistic analysis of leafhoppers (Hemiptera: Cicadellidae) associated to vineyards in the State of Rio Grande do Sul, with emphasis in the subfamily Cicadellinae (sharpshooters), which includes the main potential vectors of X. fastidiosa. Leafhopper samplings were carried out fortnightly during two years (9/2004-9/2006) in four Vitis vinifera vineyards in the municipalities of Bento Gonçalves and Farroupilha (RS). Thirtyfour leafhopper and six spittlebug species were collected, but most (98.4%) of the 3,893 specimens trapped were leafhoppers, distributed in the subfamilies Cicadellinae (60.2%), Gyponinae (34.1%), Deltocephalinae (3.8%) and Coelidinae (0.3%). The sharpshooter specimens were divided in the tribes Cicadellini (68.5%; 12 species) and Proconiini (31.5%; 11 species). Based on the faunistic indices, five species of Cicadellini, Bucephalogonia xanthophis (Berg), Dilobopterus dispar (Germar), Macugonalia cavifrons Stal, Sibovia sagata (Signoret) and Spinagonalia rubrovittata Cavichioli, and three of Proconiini, Molomea consolida (Schöder), Oncometopia facialis (Signoret) and Oncometopia fusca Melichar were prevalent in the vineyards. The high diversity of native sharpshooters in Rio Grande do Sul indicates the existence of a high risk of PD spread if the pathogen is introduced in grapevines. PMID:20498954

  18. Crustal structure of the Southern Rio Grande rift determined from seismic refraction profiling

    NASA Technical Reports Server (NTRS)

    Sinno, Y. A.; Keller, G. R.; Harder, S. H.; Daggett, P. H.; Morgan, P.

    1986-01-01

    As part of a major cooperative seismic experiment, a series of seismic refraction profiles have been recorded in south-central New Mexico with the goal of determining the crustal structure in the southern Rio Grande rift. The data gathered greatly expand the seismic data base in the area, and consist of three interlocking regional profiles: a reversed E-W line across the rift, an unreversed N-S axial line, and an unreversed SW-SE line. The reversed E-W line shows no significant dip along the Moho (32 km thick crust) and a 7.7 km/s Pn velocity. Results from the N-S axial line and the NW-SE line indicate an apparent Pn velocity of 7.95 km/s and significant dip along the Moho with crustal thinning toward the south and southeast. When interpreted together, these data indicate a crustal thinning in the southern rift of 4-6 km with respect to the northern rift and the adjacent Basin and Range province, and establish the regional Pn velocity to be approximately 7.7 km/s. These results suggest that the Rio Grande rift can be identified as a crustal feature separate and distinct from the Basin and Range province.

  19. Paleomagnetism and tectonic interpretations of the Taos Plateau volcanic field, Rio Grande rift, New Mexico

    NASA Technical Reports Server (NTRS)

    Brown, Laurie L.; Caffall, Nancy M.; Golombek, Matthew P.

    1993-01-01

    The tectonic response of the Taos Plateau volcanic field in the southern San Luis basin to late stage extensional environment of the Rio Grande rift was investigate using paleomagnetic techniques. Sixty-two sites (533 samples) of Pliocene volcanic units were collected covering four major rock types with ages of 4.7 to 1.8 Ma. Twenty-two of these sites were from stratigraphic sections of the lower, middle and upper Servilleta Basalt collected in the Rio Grande gorge at two locations 19 km apart. Flows from the lower and middle members in the southern gorge record reversed polarities, while those in Garapata Canyon are normal with an excursion event in the middle of the sequence. The uppermost flows of the upper member at both sites display normal directions. Although these sections correlate chemically, they seem to represent different magnetic time periods during the Gilbert Reversed-Polarity Chron. The data suggest the Taos Plateau volcanic field, showing no rotation and some flattening in the south and east, has acted as a stable buttress and has been downwarped by overriding of the southeastern end of the plateau by the Picuris Mountains, which make up the northern corner of the counter-clockwise rotating Espanola block.

  20. Acute lower respiratory illness in under-five children in Rio Grande, Rio Grande do Sul State, Brazil: prevalence and risk factors.

    PubMed

    Prietsch, Silvio O M; Fischer, Gilberto B; César, Juraci A; Lempek, Berenice S; Barbosa, Luciano V; Zogbi, Luciano; Cardoso, Olga C; Santos, Adriana M

    2008-06-01

    This study aimed to determine the prevalence of acute lower respiratory illness and to identify associated factors among children less than five years of age in the city of Rio Grande, southern Brazil. Using a cross-sectional survey, a standardized household questionnaire was applied to mothers or guardians. Information was collected on household conditions, socioeconomic status, and parental smoking. Prenatal care attendance, nutritional status, breastfeeding pattern, and use of health services for the children were also investigated. Data analysis was based on prevalence ratios and logistic regression, using a conceptual framework. Among 771 children studied, 23.9% presented acute lower respiratory illness. The main risk factors were previous episodes of acute lower respiratory infection or wheezing, crowding, maternal schooling less than five years, monthly family income less than US$ 200, four or more people per room, asthma in family members, and maternal smoking. Mothers 30 years or older were identified as a protective factor. These results can help define specific measures to reduce morbidity and mortality due to acute lower respiratory illness in this setting. PMID:18545768

  1. Quantifying Salinization of the Upper-Middle Rio Grande Using a Basin-Scale Water and Chloride Mass Balance Model

    NASA Astrophysics Data System (ADS)

    Mills, S. K.; Phillips, F. M.; Hogan, J. F.; Hendrickx, J. M.

    2002-12-01

    The Rio Grande is clearly undergoing salinization, manifested by a 50-fold increase in total dissolved solids content between its headwaters in Colorado and the U.S.-Mexico border. To elucidate the causes of this salinization, we conducted an eight-day synoptic sampling campaign in August 2001. This sampling included the river, its major tributaries, and major irrigation drain inflows. Along 1200 km between the river headwaters in Colorado and Fort Quitman, Texas, we collected 110 water samples with an average interval of ~10 km between sampling locales. In the laboratory, samples were analyzed for major constituents including chloride, as well as for bromide and the 36Cl/Cl ratio. Isotopic fingerprinting using the 36Cl/Cl ratio indicates that meteoric waters and deep sedimentary brines respectively account for most of the water and most of the salt inflow to the Rio Grande. The meteoric end member has a 36Cl/Cl ratio of 1100 and a Cl/Br ratio of 30; the brine end member has a 36Cl/Cl ratio of 35 and a Cl/Br ratio of 1150. Using these end member chemistries with USGS stream flow gauging data, we constructed a water- and salt- instantaneous mass balance model of the Rio Grande for the eight-day sampling interval. This model indicates that most water losses from the Rio Grande are due to evaporation from Elephant Butte reservoir, open water evaporation from irrigation ditches, and evapotranspiration of riparian and ditch-bank vegetation. The model also emphasizes the significance of salt input due to deep brine discharge to the river, particularly at the downstream ends of local sedimentary basins of the Rio Grande rift. The Rio Grande receives a smaller amount of salt from saline drains near El Paso, which may be acquiring salt from deep brine discharge as they cross over faults or other structural fluid conduits.

  2. Determining Environmental Factors Controlling Nitrogen Cycling in the Semi-Arid Rio Grande Using Nitrogen and Oxygen Isotopes

    NASA Astrophysics Data System (ADS)

    Sanchez, D. A.; Szynkiewicz, A.; Faiia, A. M.

    2015-12-01

    The Rio Grande is a semi-arid river in the American Southwest supporting agriculture and large populous centers in New Mexico and west Texas. In addition to increasing salinity, considerable increases of nitrate (NO3), up to ~50 mg/L, have been previously observed in the Rio Grande between Las Cruces, New Mexico and El Paso, Texas. This is particularly a problem during non-irrigation season when little surface water is released from upstream reservoirs, substantially reducing stream flows in the Rio Grande. While both irrigation runoff and municipal waste effluents are likely important NO3 contributors, there are no quantitative studies assessing NO3 fluxes to the Rio Grande from these two sources. Therefore, in this study we used 𝛿15N and 𝛿18O values of NO3 as environmental tracers to characterize major NO3 sources in the Rio Grande and its agricultural drains between Las Cruces and El Paso. Surface water of the semi-arid Rio Grande, drains and major wastewater treatment plants were collected in October 2014 (non-irrigation season) and August 2015 (irrigation season). The water samples from the 2014 sampling campaign showed that the 𝛿15N and 𝛿18O values of NO3 in the Rio Grande and two agricultural drains located south of El Paso varied in relatively narrow range from +9.8 to +15.7‰ and -5.9 to -0.2‰, respectively. These ranges were similar to 𝛿15N and 𝛿18O values of local wastewater treatment plants in Las Cruces and El Paso, from +8.2 to +10.2‰ and -9.7 to -2.5‰ respectively. Municipal wastewater effluents are important tributaries to the semi-arid Rio Grande in the studied area, particularly during non-irrigation season. Furthermore, irrigation of agricultural fields south of El Paso is to a large extent supported by reclaimed municipal wastewater. Consequently, these explain the observed higher contributions of NO3 from urban sources in the investigated area.

  3. Initial results of environmental monitoring in the Texas Rio Grande Valley.

    PubMed

    Garcia, S S; Ake, C; Clement, B; Huebner, H J; Donnelly, K C; Shalat, S L

    2001-06-01

    Previous studies have suggested that a segment of human disease may be attributable to environmental exposures. These may include exposure to chemicals released from a broad range of natural and man-made sources. The purpose of this study was to develop the sampling methodology and prepare a preliminary database on the presence of various organic chemicals in environmental media in two South Texas counties bordered by the Rio Grande River. A third county, located approximately 150 miles north of the Rio Grande River, was also sampled. The South Texas counties were the focus of study due to an increased incidence of anencephalic births in recent years. The environmental media that was sampled included surface water and sediment from the Rio Grande River and irrigation canals, as well as soil from adjacent cropland and pastures. Samples were collected using United States Geological Survey (USGS) quadrangle maps (7.5'; 1:24,000 scale) to identify the area of interest. At least one sampling location was established in each quadrangle. A pond sampler was used for the collection of surface water samples, while soil was collected with a stainless steel trowel. Sediment samples were collected directly in a glass jar. Solid samples were extracted in a soxhlet extractor using methylene chloride. Organic chemicals were concentrated from water samples on a Sep-Pak cartridge and the organics eluted with methanol/acetonitrile. Extracts were analyzed using GC-MS. All of the surface water samples contained aliphatic hydrocarbons and plasticizers, while soil samples contained aliphatics, plasticizers, pesticides, and industrial estrogens. Specific chemicals detected in environmental samples included atrazine and benzene dicarboxylic acid. Contaminant levels in sediments were generally higher than were detected in other media. The results demonstrate the broad variability of contaminant types and concentrations in environmental samples. Although this study presents only a very

  4. Floodplain construction of the Rio Grande at El Paso, Texas, USA: response to Holocene climate change

    NASA Astrophysics Data System (ADS)

    Hall, Stephen A.; Peterson, John A.

    2013-04-01

    The Rio Grande is one of the larger rivers in North America, and the development of its floodplain is related to Holocene climate and climate change. The late Pleistocene through early Holocene channel is characterized by a meander or braided system with lateral cutting and backfilling, resulting in the valley-wide deposition of massive to cross-bedded, fine-to-medium textured sand. The late Pleistocene-early Holocene floodplain is also the sand source for the adjacent Bolson sand sheet. The sand sheet stopped accumulating new sand 5000 yrs ago, an event directly related to the shutting off of the sand supply caused by the deposition of overbank muds that covered and sealed the floodplain surface. During the middle Holocene, the river may have dried intermittently with the floodplain becoming deflated and local sand dunes forming on the floodplain. After 5000 yrs the climate was less arid and the river shifted to a regime of increased flooding and overbank deposition of silt and clay. By 2500 yrs, a late Holocene period of wet climate resulted in further overbank deposition and the formation of a cumulic Mollisol across the floodplain, the Socorro paleosol. The period of wet climate corresponds to the Audubon Neoglacial and active rock glaciers in the southern Rocky Mountains, speleothem growth in nearby caves, and other evidence for wet-cool conditions in the region. After 1000 yrs, the climate became drier, and the deposition and accumulation of overbank muds by the flooding Rio Grande came to a halt. Even though the river has flooded often in historic times, and presumably during late prehistoric times as well, there is little evidence for deposition of overbank sediments on the floodplain since A.D. 1000. Accordingly, the present-day surface of the Lower Valley is ten centuries old. Three channels occur on the US side of the Lower Valley floodplain, and during the past 2500 yrs stream flow has shifted from one to the other by the avulsion process of channel

  5. Deformation in the Basin & Range Province and Rio Grande Rift using InSAR Time Series

    NASA Astrophysics Data System (ADS)

    Taylor, H.; Pisaniello, M.; Pritchard, M. E.

    2012-12-01

    High heat flow in the Basin and Range Province and Rio Grande Rift has been attributed to partial melting in the crust and upper mantle as a result of ongoing extension (e.g. Lachenbruch 1978). We would then expect to observe surface deformation in areas with actively moving magmatic fluids. The distribution of these magmatic fluids has implications for the rheology of the crust and upper mantle. For this study, we use InSAR to locate deformation due to magmatic sources as well as localized hydrologic deformation. While our focus is magmatic deformation, hydrologic signals are important for correcting geodetic data used to monitor tectonic activity. InSAR is a suitable technique for a large study in the Basin and Range and Rio Grande Rift since SAR acquisitions are both numerous and temporally extensive in these regions. We use ERS-1, ERS-2, and ENVISAT SAR images from 1992-2010 to create time series' with interferograms up to 1800km long from both ascending and descending satellite tracks. Each time series has an average of 100 interferograms reducing the atmospheric noise that masks small deformation signals in single interferograms. The time series' results are validated using overlapping tracks and are further compared to signals identified in previous geophysical studies (e.g. Reilinger and Brown 1980, Massonnet et al 1997, Finnegan and Pritchard 2009). We present results for several areas of deformation in the Basin & Range Province and Rio Grande Rift. An agricultural area near Roswell, NM exhibits seasonal uplift and subsidence of ±3.5cm/yr between 1992 and 1999. Results indicate subsidence on the order of 1cm/yr and uplift of 2cm/yr at the Raft River power plant, ID that is likely related to the start of geothermal fluid production and injection. Just north of the Raft River plant, we detect what appears to be rapid agricultural subsidence in an area extending for 50km. We discuss subsidence of ~2cm/yr in Escalante Valley, UT that is comparable to

  6. Leishmaniasis transmission in an ecotourism area: potential vectors in Ilha Grande, Rio de Janeiro State, Brazil

    PubMed Central

    2013-01-01

    Background The south coast of Rio de Janeiro State, in Brazil, is endemic for cutaneous and visceral leishmaniases and is frequently visited by tourists from different parts of the world. Since the complex epidemiology of leishmaniases demands local studies, the goal of this study was to investigate the phlebotomine sand fly fauna and leishmaniases transmission in Ilha Grande, an ecotourism area of Angra dos Reis municipality. Methods Sand fly fauna was sampled in three monitoring stations using HP light traps in domiciles, peridomiciles and forests. Species abundance was evaluated by the Index of Species Abundance. A Leishmania natural infection survey was done using multiplex PCR and dot blot hybridization. Results During 15 consecutive months of sand fly monitoring, 1093 specimens from 16 species were captured. The potential leishmaniases vectors found were Lutzomyia (Nyssomyia) intermedia, L. migonei, L. (N.) flaviscutellata, L. (Psychodopygus) ayrozai and L. (Lutzomyia) longipalpis. Five species were new records in Ilha Grande: L. (Sciopemyia) microps, L. termitophila, L. firmatoi, L. rupicola and L. (P.) ayrozai. Higher species richness was found inside forest areas, although potential leishmaniases vectors were present in deforested areas, peridomiciles and inside houses. Lutzomyia (N.) intermedia and L. migonei were the most abundant species. Females of L. migonei showed a high rate (10.3%) of natural infection by Leishmania (Viannia) sp., probably Leishmania (V.) braziliensis. Conclusions The detection of leishmaniases transmission and potential vectors in Ilha Grande is of public health concern, especially because tourists are frequently visiting the island. Besides reinforcing the epidemiological importance of L. (N.) intermedia in Rio de Janeiro State, the role of L. migonei in cutaneous leishmaniasis transmission is highlighted with its high rate of Leishmania natural infection. The finding of L. (L.) longipalpis confirmed the human autochthonous case

  7. Development and impact of biological control of giant reed, Arundo donax, in the Rio Grande Basin of the U.S. and Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Giant reed (Arundo donax L.) also known as giant cane or carrizo cane, is an exotic perennial grass that has infested over 60,000 hectares along riparian corridors in the southwestern U.S. The most severe infestations are in the Lower Rio Grande Basin, where giant reed along the Rio Grande and Mexic...

  8. a Microgravity Survey to Determine the Extent of AN Andesitic Sill that Intrudes across the Rio Grande River Basin, Rio Grande Rift Valley, Sunland Park, New Mexico

    NASA Astrophysics Data System (ADS)

    Baker, L. A.; Shinagel, S.; Villalobos, J. I.; Avila, V.; Montana, C. J.; Kaip, G.

    2012-12-01

    In Sunland Park, NM, there is an andesite outcrop near the bank of the Rio Grande (called the River Andesite) which does not match the surrounding sedimentary deposition. Studies of the River Andesite by Garcia (1970) indicate the outcrop is petrologically similar to the Muleros Andesite of Mt. Cristo Rey located several km to the south. A limited GPR and magnetic survey conducted by UTEP students in 2008 suggested the River Andesite was part of a dike, although Garcia mapped smaller outcrops of andesite ~300 m west of the river that may be part of the same body. We have recently (June 2012) found large andesite boulders that may be the outcrops Garcia mapped, although it is uncertain whether these boulders are in-situ. We initially collected microgravity and magnetic data in a small region near the river outcrop in December 2011 to determine the extent of the outcrop. Our preliminary modeling of these data showed the river outcrop appeared to merge with a more extensive igneous body at depth. Ground conductivity data collected near the river outcrop in March 2012 suggested that the outcrop impacts groundwater flow and sediment deposition adjacent to the river. From May through July 2012 we have been collecting additional microgravity data on a grid with 100-200 m spacing extending ~ 500 m from both sides of the river outcrop to better determine the extent of the buried andesite body. We also plan to conduct GPR and magnetic surveys near the recently discovered andesite boulders to determine if these are truly in-situ and part of the same igneous body as the river outcrop. Our eventual goal is to determine how extensive the andesite unit is and how it may impact groundwater flow and flooding in this area of growing urbanization.

  9. Rio Grande Erosion Potential Demonstration - Report for the National Border Technology Program

    SciTech Connect

    JEPSEN, RICHARD A.; ROBERTS, JESSE D.; LANGFORD, RICHARD; GAILANI, JOSEPH

    2001-11-01

    This demonstration project is a collaboration among DOE, Sandia National Laboratories, the University of Texas, El Paso (UTEP), the International Boundary and Water Commission (IBWC), and the US Army Corps of Engineers (USACE). Sandia deployed and demonstrated a field measurement technology that enables the determination of erosion and transport potential of sediments in the Rio Grande. The technology deployed was the Mobile High Shear Stress Flume. This unique device was developed by Sandia's Carlsbad Programs for the USACE and has been used extensively in collaborative efforts on near shore and river systems throughout the United States. Since surface water quantity and quality along with human health is an important part of the National Border Technology Program, technologies that aid in characterizing, managing, and protecting this valuable resource from possible contamination sources is imperative.

  10. Second century megadrought in the Rio Grande headwaters, Colorado: How unusual was medieval drought?

    NASA Astrophysics Data System (ADS)

    Routson, Cody C.; Woodhouse, Connie A.; Overpeck, Jonathan T.

    2011-11-01

    A new tree-ring record from living and remnant bristlecone pine (Pinus aristata) wood from the headwaters region of the Rio Grande River, Colorado is used in conjunction with other regional records to evaluate periods of unusually severe drought over the past two millennia (B.C. 268 to A.D. 2009). Our new record contains a multi-century period of unusual dryness between 1 and 400 A.D., including an extreme drought during the 2nd century. Characterized by almost five decades of drought (below average ring width), we hypothesize this megadrought is equally, if not more severe than medieval period megadroughts in this region. Published paleoclimate time series help define the spatial extent, severity, and potential causes of the 2nd century megadrought. Furthermore, this early period of unusual dryness has intriguing similarities to later medieval period aridity. Our findings suggest we should anticipate similar severe drought conditions in an even warmer and drier future.

  11. Earth resources evaluation for New Mexico by LANDSAT-2. [Rio Grande

    NASA Technical Reports Server (NTRS)

    Linden, K. V. (Principal Investigator); Feldman, S. C.; Inglis, M. H.; Kottlowski, F. E.; Tabet, D. E.

    1975-01-01

    The author has identified the following significant results. The Middle Rio Grande project has not yet progressed to the point where mineral exploration sites can be chosen; however, there does appear to be some correlation between the known structure and mineral deposits and the LANDSAT lineament map. A circular feature identified in the southern Magdalena Mountains on LANDSAT-1 imagery agrees well with the location of a newly proposed caldron complex. Several recognized and unrecognized circular features were identified on imagery of the Mogollon-Datil volcanic field. A check of aeromagnetic maps for New Mexico found that the circular features on the LANDSAT imagery showed up as areas of generally high magnetic intensity.

  12. Solute Sources and Budget for the Rio Grande above El Paso, Texas

    NASA Astrophysics Data System (ADS)

    Hogan, J. F.; Phillips, F. M.; Hendrickx, J. M.

    2001-12-01

    Issues of water quality, especially salinity, limit the use of water resources from the Rio Grande. Identification and quantification of salinity sources is critical for improved river management. In the headwater region salts are typically derived from atmospheric deposition and chemical weathering reactions. Salinity increases during transit may result from both natural (saline groundwater, hydrothermal springs and dissolution of evaporite deposits) and anthropogenic (agricultural return flow and wastewater from sewage treatment plants) sources. These increases are magnified by evapotranspiration (this includes evaporation from open water, transpiration from irrigated agriculture and transpiration from natural riparian areas). With multiple salinity sources and evapotranspiration acting simultaneously, understanding the solute balance for the Rio Grande at a level needed for improved river management is difficult. We have conducted synoptic sampling of the Rio Grande from the headwaters in Colorado to south of El Paso, Texas. Sampling was conducted in January and August of 2000 and 2001. The total dissolved solids content (TDS) of the Rio Grande increases from < 50 mg/L in headwater regions of Colorado to > 2000 mg/L south of El Paso, Texas. The Cl/Br (wt/wt) ratio for river water increases from ~50 in the headwaters (typical for atmospheric deposition) to ~700 in the lower basin. This increase in Cl/Br ratio demonstrates the importance of additional salinity sources. Three end-members are recognized using Cl/Br mixing plots for winter samples: atmospheric deposition, a hydrothermal end-member localized around Truth of Consequences, NM, and a third end-member that may represent groundwater. Samples collected during the summer months are shifted off the winter mixing lines indicating concentration through ET. Increases in salinity were not a simple function of distance downriver, but rather occurred in a series of steps. Some of these steps are correlated with

  13. Effects of Soil Solarization on Rotylenchulus reniformis in the Lower Rio Grande Valley of Texas.

    PubMed

    Heald, C M; Robinson, A F

    1987-01-01

    Soil solarization was evaluated for control of Rotylenchulus reniformis in the lower Rio Grande Valley of Texas. In field experiments, solarization significantly reduced soil nematode population densities 0-15 cm deep and increased yields of lettuce and cowpea. The length of time required for 90% mortality of nematodes in soil heated under controlled conditions in the laboratory varied from 25 hours to less than 1 hour between 41 and 47 C. Daily exposures of nematode-infested soil to lethal temperatures for sublethal time periods had a cumulative lethal effect. In water, vermiform stages required up to 10 days to recover from sublethal thermal stress. Eggs were similar to juveniles in their sensitivity to high temperatures. Lethal time-temperatures under controlled conditions were in general agreement with field results. PMID:19290112

  14. Structural evolution of the Abiquiu embayment, Rio Grande Rift: Implications for the development of transfer zones.

    NASA Astrophysics Data System (ADS)

    Hicks, R. T.; Murphy, M. A.

    2006-12-01

    The Abiquiu embayment is located along the boundary between the Colorado Plateau and the Rio Grande rift in north central New Mexico. It is an early rift basin bordered by the Canones fault system on its west side that is oblique to the regional trend of the Rio Grande rift and lies within a region where the polarity of the rift changes. Knowledge of the geometry, kinematics, and slip history of the basin-bounding faults is important in understanding segmentation of the Rio Grande rift and may shed light on the development of transform zones in general. We present geologic mapping, stratigraphic analysis and structural analyses of geologic features in the Abiquiu area to assess the role of Abiquiu embayment in the development of the Rio Grande rift. Our mapping shows that the Canones fault system is an east-dipping, oblique normal fault system that strikes northeast for approximately 20 km. It juxtaposes Permian and Triassic age formations in its footwall against upper Jurassic rocks and 300 m of Tertiary basin fill in its hanging wall. Attitudes of pre-rift strata in the hanging wall define a basin-scale rollover structure, which implies the fault system is listric at depth. Fault slip data collected from the Canones fault system shows the mean slip direction is ENE, which yields nearly equal components of left- slip and normal dip-slip. Mode 1 fractures adjacent to the fault system strike between N20E and N47E, an orientation similar to the strike of basaltic dikes several kilometers east of the surface trace of the Canones fault system. Restoration of the contact between Permian and Triassic-age rocks in a direction parallel to the mean slip direction yields slip estimates that show along strike changes. In the southern part of the study area we estimate 300 m of net slip. In the north, we estimate approximately 425 m. The majority of the total slip occurred before deposition of the 8-10 Ma Lobato basalt. Offset of this basalt unit is less than 50 m, implying

  15. Engaging Teachers and Students in the Rio Grande Valley in Earth and Space Science: Chapter II

    NASA Astrophysics Data System (ADS)

    Ries, J. G.; Baguio, M.; Ramirez, S.

    2012-08-01

    In the summer of 2010, we received a NASA Science, Technology, Engineering, and Mathematics (STEM) education Cooperative Agreement Notice to prepare teachers in the Rio Grande Valley to become certified to teach the new fourth year capstone courses in astronomy and earth and space science. During the 2010 ASP conference, we reported on the earth and space science resources provided, guidance in curriculum development, and training in classroom activities. This two-year project began with the two 2010 summer workshops that concentrated on earth and space sciences, and were then followed up with two weekend training sessions, on-line training, and a Family Science Night during the school year. An important requirement of the new fourth year courses is a field investigation conducted by students. We offered mini-grants for proposing teachers to support a field investigation. Here we highlight the outcomes of these follow-up programs and the two weeklong astronomy workshops in June 2011 in Edinburg, Texas.

  16. Oligocene basaltic volcanism of the northern Rio Grande Rift: San Luis Hills, Colorado

    USGS Publications Warehouse

    Thompson, R.A.; Johnson, C.M.; Mehnert, H.H.

    1991-01-01

    The inception of the Rio Grande Rift in northern New Mexico and southern Colorado was accompanied by voluminous mafic volcanism preserved in part as erosional remnants on an intrarift horst within the current axial rift graben of the San Luis Valley. Major and trace element constraints support a petrogenetic model of fractionation plus lower crustal assimilation for petrologic suites within the San Luis Hills rocks, although the model cannot relate lavas for the entire series to a common parent. Most mafic lavas of the San Luis Hills were evolved (Mg # <60) and contaminated by LREE-enriched silicic partial melts of granulitic lower crust depleted in Rb, Th, and U. However, relatively noncontaminated lavas can be identified and indicate at least two mantle source regions were involved. -from Authors

  17. An international borderland of concern: Conservation of biodiversity in the Lower Rio Grande Valley

    USGS Publications Warehouse

    Leslie,, David M., Jr.

    2016-01-01

    The Lower Rio Grande Valley (LRGV) of southern Texas is located on the United States-Mexico borderland and represents a 240-kilometer (150-mile) linear stretch that ends at the Gulf of Mexico. The LRGV represents a unique transition between temperate and tropical conditions and, as such, sustains an exceptionally high diversity of plants and animals—some of them found in few, or no other, places in the United States. Examples include Leopardus pardalis albescens (northern ocelot) and Falco femoralis septentrionalis (northern aplomado falcon)—both endangered in the United States and emblematic of the LRGV. The U.S. Fish and Wildlife Service (USFWS) manages three national wildlife refuges (Santa Ana, Lower Rio Grande Valley, and Laguna Atascosa) that together make up the South Texas Refuge Complex, which actively conserves biodiversity in about 76,006 hectares (187,815.5 acres) of native riparian and upland habitats in the LRGV. These diminished habitats harbor many rare, threatened, and endangered species. This report updates the widely used 1988 USFWS biological report titled “Tamaulipan Brushland of the Lower Rio Grande Valley of South Texas: Description, Human Impacts, and Management Options” by synthesizing nearly 400 peer-reviewed scientific publications that have resulted from biological and sociological research conducted specifically in the four Texas counties of the LRGV in the past nearly 30 years. This report has three goals: (1) synthesize scientific insights gained since 1988 related to the biology and management of the LRGV and its unique biota, focusing on flora and fauna of greatest conservation concern; (2) update ongoing challenges facing Federal and State agencies and organizations that focus on conservation or key natural resources in the LRGV; and (3) redefine conservation opportunities and land-acquisition strategies that are feasible and appropriate today, given the many new and expanding constraints that challenge conservation

  18. A toxic cyanobacterial bloom in an urban coastal lake, Rio Grande do Sul state, Southern Brazil

    PubMed Central

    de Carvalho, Luciana Retz; Pipole, Fernando; Werner, Vera Regina; Laughinghouse IV, Haywood Dail; de Camargo, Antonio Carlos M.; Rangel, Marisa; Konno, Katsuhiro; Sant’ Anna, Célia Leite

    2008-01-01

    Reports of cyanobacterial blooms developing worldwide have considerably increased, and, in most cases, the predominant toxins are microcystins. The present study reports a cyanobacterial bloom in Lake Violão, Torres, Rio Grande do Sul State, in January 2005. Samples collected on January 13, 2005, were submitted to taxonomical, toxicological, and chemical studies. The taxonomical analysis showed many different species of cyanobacteria, and that Microcystis protocystis and Sphaerocavum cf. brasiliense were dominant. Besides these, Microcystis panniformis, Anabaena oumiana, Cylindrospermopsis raciborskii, and Anabaenopsis elenkinii f. circularis were also present. The toxicity of the bloom was confirmed through intraperitoneal tests in mice, and chemical analyses of bloom extracts showed that the major substance was anabaenopeptin F, followed by anabaenopeptin B, microcystin-LR, and microcystin-RR. PMID:24031304

  19. Independent Life Skills among psychosocial care network users of Rio Grande do Sul, Brazil.

    PubMed

    Rodrigues, Cândida Garcia Sinott Silveira; Jardim, Vanda Maria da Rosa; Kantorski, Luciane Prado; Coimbra, Valeria Cristina Christello; Treichel, Carlos Alberto Dos Santos; Francchini, Beatriz; Bretanha, Andreia Ferreira; Neutzling, Aline Dos Santos

    2016-08-01

    This is a cross-sectional study that aims to identify the prevalence of lower independent living skills and their associations in 390 users of psychiatric community-based services in the state Rio Grande do Sul, Brazil. For tracing the outcome it was used the "scale Independent Living Skills Survey", adopting a cut-off value lower than 2. The crude and adjusted analyses were conducted on binary logistic regressions and they considered a hierarchical model developed through a systematic literature review. In adjusted analysis the level of the same variables were adjusted to each other and to previous levels. The statistical significance remained as a < 0.05 p-value. The prevalence of smaller independent living skills was 33% and their associations were: younger age; no partner; lower education; resident at SRT; diagnosis of schizophrenia and younger diagnosis. PMID:27557029

  20. The prevalence of multiple sclerosis in Santa Maria, Rio Grande do Sul, Brazil.

    PubMed

    Finkelsztejn, Alessandro; Lopes, Juarez Silva; Noal, Janaína; Finkelsztejn, Juliana M

    2014-02-01

    Multiple sclerosis (MS) is one of the leading causes of neurologic deficits in young adults and can lead to physical, intellectual and emotional problems. Approved treatments are expensive and are among the 10 highest budgets of the Brazilian Health Ministry. Given the diverse prevalence of MS among Brazilian regions, it is important to determine prevalence rates across the country. Seven studies have assessed MS in Brazil and reported rates ranging from 15 cases to 18 cases per 100,000 inhabitants. It has been hypothesized that this rate is even higher in southern Brazil, which has a high proportion of European heritage (mostly German and Italian) immigrants. Here, we report that the prevalence of MS in the city of Santa Maria, Rio Grande do Sul, Brazil, is 27.2 cases/100,000 inhabitants. PMID:24604362

  1. Geodetic measurement of horizontal deformation across the Rio Grande rift near Socorro, New Mexico.

    USGS Publications Warehouse

    Savage, J.C.; Lisowski, M.; Prescott, W.H.; Sanford, A.R.

    1980-01-01

    Trilateration surveys of a geodetic network across the Rio Grande rift near Socorro, New Mexico, in 1972, 73, 76 and 79 have failed to detect any significant strain accumulation. The surveys place an upper bound (95% confidence limit) of 1 mm/a (a = years) on EW spreading across the rift in 1972-79. There is marginal evidence from triangulation for an episode of EW spreading across the rift within the interval 1954-72. The trilateration network lies on the S flank of an uplift caused by magma intrusion into a midcrustal sill during this century according to Reilinger and Oliver. The horizontal deformation induced by sill inflation is sufficiently small that continued uplift during 1972-79 cannot be excluded by the observed absence of significant horizontal deformation.-Authors

  2. Utilization of LANDSAT orbital imagery in the soil survey processes at Rio Grande do Norte state

    NASA Technical Reports Server (NTRS)

    Formaggio, A. R. (Principal Investigator)

    1984-01-01

    Pedologic photointerpretative criteria adapted to LANDSAT orbital imagery were used: drainage (pattern, integration degree, density and uniformity degree); relief (pattern, dissection degree and crest lines); photographic texture, photographic tonnality, and the land use (type, glebas size and intensity of use). The performance of the imagery as an auxiliar tool in the soil survey processes, at Rio Grande do Norte State was evaluated. The drainage and relief elements were easily extracted from the imagery and also ones that provided the greatest deductive possibility about pedologic boundaries. Other analyzed criteria were considered only auxiliaries, corroborating some soil limits in the evidences convergence phase. The principal pedologic dominions of the 30,000 sq km are covered by the same LANDSAT image (WRS 359/16) were delimited with good precision: (1) fluvial plains, beaches, dunes and coastal mangroves; (2) North Coast line Plateau; (3) Acu Sandstone Zone; (4) residual plateaus of the Tertiary; and (6) plains of the embasement.

  3. [Use of dental services by preschool children in Canela, Rio Grande do Sul State, Brazil].

    PubMed

    Kramer, Paulo Floriani; Ardenghi, Thiago Machado; Ferreira, Simone; Fischer, Laura de Almeida; Cardoso, Luciana; Feldens, Carlos Alberto

    2008-01-01

    The aim of this study was to assess the use of dental services and age at first dental visit in preschool children in Canela, Rio Grande do Sul State, Brazil. A representative sample of under-five children was surveyed on National Children's Vaccination Day. Children's parents completed questionnaires containing socio-demographic data and age at first dental visit. Data were analyzed using multiple logistic regression. 192 children were examined. 13.3% of the sample had already visited the dentist at least once, but only 4.3% had their first dental visit by one year of age. The number of children who had already visited a dentist increased with age. Girls showed higher odds of having visited a dentist (OR = 1.46; 95%CI: 1.01-2.1). Public health strategies are needed to determine the effectiveness of health promotion and improve the use of dental services by preschool children. PMID:18209843

  4. Case study Middle Rio Grande Basin, New Mexico, USA: Chapter 12

    USGS Publications Warehouse

    Plummer, L.N.; Sanford, W.

    2013-01-01

    Chemical and isotopic patterns in groundwater can record characteristics of water sources, flow directions, and groundwater-age information. This hydrochemical information can be useful in refining conceptualization of groundwater flow, in calibration of numerical models of groundwater flow, and in estimation of paleo and modern recharge rates. This case study shows how chemical and isotopic data were used to characterize sources and flow of groundwater in the Middle Rio Grande Basin (MRGB) of New Mexico, USA. The 14C model ages of the groundwater samples are on the tens of thousands of year timescale. These data changed some of the prevailing ideas about flow in the MRGB, and were used to improve a numerical model of the aquifer system.

  5. Pathogenic Landscape of Transboundary Zoonotic Diseases in the Mexico-US Border Along the Rio Grande.

    PubMed

    Esteve-Gassent, Maria Dolores; Pérez de León, Adalberto A; Romero-Salas, Dora; Feria-Arroyo, Teresa P; Patino, Ramiro; Castro-Arellano, Ivan; Gordillo-Pérez, Guadalupe; Auclair, Allan; Goolsby, John; Rodriguez-Vivas, Roger Ivan; Estrada-Franco, Jose Guillermo

    2014-01-01

    Transboundary zoonotic diseases, several of which are vector borne, can maintain a dynamic focus and have pathogens circulating in geographic regions encircling multiple geopolitical boundaries. Global change is intensifying transboundary problems, including the spatial variation of the risk and incidence of zoonotic diseases. The complexity of these challenges can be greater in areas where rivers delineate international boundaries and encompass transitions between ecozones. The Rio Grande serves as a natural border between the US State of Texas and the Mexican States of Chihuahua, Coahuila, Nuevo León, and Tamaulipas. Not only do millions of people live in this transboundary region, but also a substantial amount of goods and people pass through it everyday. Moreover, it occurs over a region that functions as a corridor for animal migrations, and thus links the Neotropic and Nearctic biogeographic zones, with the latter being a known foci of zoonotic diseases. However, the pathogenic landscape of important zoonotic diseases in the south Texas-Mexico transboundary region remains to be fully understood. An international perspective on the interplay between disease systems, ecosystem processes, land use, and human behaviors is applied here to analyze landscape and spatial features of Venezuelan equine encephalitis, Hantavirus disease, Lyme Borreliosis, Leptospirosis, Bartonellosis, Chagas disease, human Babesiosis, and Leishmaniasis. Surveillance systems following the One Health approach with a regional perspective will help identifying opportunities to mitigate the health burden of those diseases on human and animal populations. It is proposed that the Mexico-US border along the Rio Grande region be viewed as a continuum landscape where zoonotic pathogens circulate regardless of national borders. PMID:25453027

  6. Stratigraphy and sedimentology of Kincaid Formation, Midway Group (Paleocene), Upper Rio Grande Embayment, Texas

    SciTech Connect

    Roy, E.C. Jr.

    1984-09-01

    Sedimentary rocks of the Kincaid Formation crop out along the northern and western edges of the Rio Grande Embayment. Siltstones are exposed at the type locality of the Kincaid Formation along the Frio River in Uvalde County, Texas. On the east and south, the Kincaid Formation changes facies to richly fossiliferous carbonate rocks; however, basinward, it grades into a shale facies that contains interbedded units of fine-grained sandstone. At the type locality of the Kincaid Formation, approximately 30 ft (9 m) of massive siltstone grades upward into a very silty limestone unit. Bedding is poorly defined throughout the section, largely the result of intensive bioturbation. The grain size of the siltstone increases upward, ranging from medium to coarse. Clay content in the siltstone decreases upward as the amount of calcareous material increases. The upper 4-6 ft (1.2-1.8 m) may actually be considered a silty limestone. A dramatic facies change is present along the outcrop both east and south of the type section. To the east, the Kincaid Formation is composed of glauconitic and highly fossiliferous limestone. The siltstone present at the type locality thins eastward and is absent less than 20 mi (32 km) away. Eighty miles (130 km) to the south, along the Rio Grande River, approximately 45 ft (14 m) of limestone and shale comprise the Kincaid Formation. These early Paleocene sediments are interpreted to be shallow marine in origin. The siltstone represents a shallow sublittoral shoreface environment whereas the limestones on the east and south were deposited in shallow nearshore environments beyond the reach of clastic deposition.

  7. Ages of Quaternary Rio Grande terrace-fill deposits, Albuquerque area, New Mexico

    USGS Publications Warehouse

    Cole, J.C.; Mahan, S.A.; Stone, B.D.; Shroba, R.R.

    2007-01-01

    Results from luminescence dating on 13 samples from the Albuquerque area show that major-drainage fluvial deposits represent significant periods of aggradation that formed paired, correlatable terraces on the east and west margins of the Rio Grande valley. The youngest terrace fills (Primero Alto) formed during late Pleistocene as a result of streamflow variations with climate cooling during Marine Oxygen-Isotope Stage 3; our ages suggest aggradation of the upper part of the fill occurred at about 47-40 ka. Deposits of the second (Segundo Alto) terraces reached maximum height during climate cooling in the early part of Marine Oxygen-Isotope Stage 5 as late as 90-98 ka (based on dated basalt flows). Our luminescence ages show considerable scatter and tend to be younger (range from 63 ka to 162 ka). The third (Tercero Alto) and fourth (Cuarto Alto) terraces are dated on the basis of included volcanic tephra. Tercero Alto terrace-fill deposits contain the Lava Creek B tephra (639 ka), and Cuarto Alto terrace-fill deposits contain tephra of the younger Bandelier Tuff eruption (1.22 Ma), the Cerro Toledo Rhyolite (1.47 Ma), and the older Bandelier Tuff eruption (1.61 Ma). These periods of aggradation culminated in fluvial terraces that are preserved at maximum heights of 360 ft (Cuarto Alto), 300 ft (Tercero Alto), 140 ft (Segundo Alto), and 60 ft (Primero Alto) above the modern flood-plain. Despite lithologic differences related to local source-area contributions, these terracefill deposits can be correlated across the Rio Grande and up- and down-valley for tens of miles based on maximum height of the terrace above the modern floodplain.

  8. Ages of Quaternary Rio Grande terrace-fill deposits, Albuquerque area, New Mexico

    USGS Publications Warehouse

    James Channing Cole; Mahan, Shannon; Stone, Byron D.; Shroba, Ralph R.

    2007-01-01

    Results from luminescence dating on 13 samples from the Albuquerque area show that major-drainage fluvial deposits represent significant periods of aggradation that formed paired, correlatable terraces on the east and west margins of the Rio Grande valley . The youngest terrace fills (Primero Alto) formed during late Pleistocene as a result of streamflow variations with climate cooling during Marine Oxygen-Isotope Stage 3; our ages suggest aggradation of the upper part of the fill occurred at about 47–40 ka . Deposits of the second (Segundo Alto) terraces reached maximum height during climate cooling in the early part of Marine Oxygen-Isotope Stage 5 as late as 90–98 ka (based on dated basalt flows) . Our luminescence ages show considerable scatter and tend to be younger (range from 63 ka to 162 ka) . The third (Tercero Alto) and fourth (Cuarto Alto) terraces are dated on the basis of included volcanic tephra. Tercero Alto terrace-fill deposits contain the Lava Creek B tephra (639 ka), and Cuarto Alto terrace-fill deposits contain tephra of the younger Bandelier Tuff eruption (1 .22 Ma), the Cerro Toledo Rhyolite (1 .47 Ma), and the older Bandelier Tuff eruption (1 .61 Ma). These periods of aggradation culminated in fluvial terraces that are preserved at maximum heights of 360 ft (Cuarto Alto), 300 ft. (Tercero Alto), 140 ft (Segundo Alto), and 60 ft. (Primero Alto) above the modern floodplain. Despite lithologic differences related to local source-area contributions, these terracefill deposits can be correlated across the Rio Grande and up- and down-valley for tens of miles based on maximum height of the terrace above the modern floodplain.

  9. Use of a dynamic simulation model to understand nitrogen cycling in the middle Rio Grande, NM.

    SciTech Connect

    Meixner, Tom; Tidwell, Vincent Carroll; Oelsner, Gretchen; Brooks, Paul; Roach, Jesse D.

    2008-08-01

    Water quality often limits the potential uses of scarce water resources in semiarid and arid regions. To best manage water quality one must understand the sources and sinks of both solutes and water to the river system. Nutrient concentration patterns can identify source and sink locations, but cannot always determine biotic processes that affect nutrient concentrations. Modeling tools can provide insight into these large-scale processes. To address questions about large-scale nitrogen removal in the Middle Rio Grande, NM, we created a system dynamics nitrate model using an existing integrated surface water--groundwater model of the region to evaluate our conceptual models of uptake and denitrification as potential nitrate removal mechanisms. We modeled denitrification in groundwater as a first-order process dependent only on concentration and used a 5% denitrification rate. Uptake was assumed to be proportional to transpiration and was modeled as a percentage of the evapotranspiration calculated within the model multiplied by the nitrate concentration in the water being transpired. We modeled riparian uptake as 90% and agricultural uptake as 50% of the respective evapotranspiration rates. Using these removal rates, our model results suggest that riparian uptake, agricultural uptake and denitrification in groundwater are all needed to produce the observed nitrate concentrations in the groundwater, conveyance channels, and river as well as the seasonal concentration patterns. The model results indicate that a total of 497 metric tons of nitrate-N are removed from the Middle Rio Grande annually. Where river nitrate concentrations are low and there are no large nitrate sources, nitrate behaves nearly conservatively and riparian and agricultural uptake are the most important removal mechanisms. Downstream of a large wastewater nitrate source, denitrification and agricultural uptake were responsible for approximately 90% of the nitrogen removal.

  10. Forest Cover Change and Soil Erosion in Toledo's Rio Grande Watershed

    NASA Astrophysics Data System (ADS)

    Chicas, S.; Omine, K.

    2015-04-01

    Toledo, the southernmost district, is the hub of Belize's Mayan population, descendants of the ancient Mayan civilization. The Toledo District is primarily inhibited by Kekchi and Mopan Mayans whose subsistence needs are met by the Milpa slash-and-burn agricultural system and the extraction of forest resources. The poverty assessment in the country indicates that Toledo is the district with the highest percentage of household an individual indigence of 37.5 % and 49.7 % respectively. Forest cover change in the area can be attributed to rapid population growth among the Maya, together with increase in immigration from neighboring countries, logging, oil exploration and improvement and construction of roads. The forest cover change analysis show that from 2001 to 2011 there was a decrease of Lowland broad-leaved wet forest of 7.53 km sq, Shrubland of 4.66 km sq, and Wetland of 0.08 km sq. Forest cover change has resulted in soil erosion which is causing the deterioration of soils. The land cover types that are contributing the most to total erosion in the Rio Grande watershed are no-forest, lowland broad-leaved wet forest and submontane broad-leaved wet forest. In this study the Revised Universal Soil Loss Equation (RUSLE) was employed in a GIS platform to quantify and assess forest cover change and soil erosion. Soil erosion vulnerability maps in Toledo's Rio Grande watershed were also created. This study provides scientifically sound information in order to understand and respond effectively to the impacts of soil erosion in the study site.

  11. Water quality and amphibian health in the Big Bend region of the Rio Grande Basin

    USGS Publications Warehouse

    Sharma, Bibek; Hu, F.; Carr, J.A.; Patino, Reynaldo

    2011-01-01

    Male and female Rio Grande leopard frogs (Rana berlandieri) were collected in May 2005 from the main stem and tributaries of the Rio Grande in the Big Bend region of Texas. Frogs were examined for (1) incidence of testicular ovarian follicles in males; (2) thyroid epithelial cell height, a potential index of exposure to thyroid-disrupting contaminants; and (3) incidence of liver melanomacrophage aggregates, a general index of exposure to contaminants. Standard parameters of surface water quality and concentrations of selected elements, including heavy metals, were determined at each frog collection site. Heavy metals also were measured in whole-frog composite extracts. Water cadmium concentrations in most sites and chloride concentrations in the main stem exceeded federal criteria for freshwater aquatic life. Mercury was detected in frogs from the two collection sites in Terlingua Creek. There was a seventeen percent incidence of testicular ovarian follicles in male frogs. Mean thyroid epithelial cell height was greater in frogs from one of the Terlingua Creek sites (Terlingua Abajo). No differences were observed in the incidence of hepatic macrophage aggregates among sites. In conclusion, although potential cause-effect relationships between indices of habitat quality and amphibian health could not be established, the results of this study raise concerns about the general quality of the aquatic habitat and the potential long-term consequences to the aquatic biota of the Big Bend region. The presence of ovarian follicles in male frogs is noteworthy but further study is necessary to determine whether this phenomenon is natural or anthropogenically induced.

  12. Seismic Anisotropy Beneath the Eastern Flank of the Rio Grande Rift

    NASA Astrophysics Data System (ADS)

    Benton, N. W.; Pulliam, J.

    2015-12-01

    Shear wave splitting was measured across the eastern flank of the Rio Grande Rift (RGR) to investigate mechanisms of upper mantle anisotropy. Earthquakes recorded at epicentral distances of 90°-130° from EarthScope Transportable Array (TA) and SIEDCAR (SC) broadband seismic stations were examined comprehensively, via the Matlab program "Splitlab", to determine whether SKS and SKKS phases indicated anisotropic properties. Splitlab allows waveforms to be rotated, filtered, and windowed interactively and splitting measurements are made on a user-specified waveform segment via three independent methods simultaneously. To improve signal-to-noise and improve reliability, we stacked the error surfaces that resulted from grid searches in the measurements for each station location. Fast polarization directions near the Rio Grande Rift tend to be sub-parallel to the RGR but then change to angles that are consistent with North America's average plate motion, to the east. The surface erosional depression of the Pecos Valley coincides with fast polarization directions that are aligned in a more northerly direction than their neighbors, whereas the topographic high to the east coincides with an easterly change of the fast axis.The area above a mantle high velocity anomaly discovered separately via seismic tomography which may indicate thickened lithosphere, corresponds to unusually large delay times and fast polarization directions that are more closely aligned to a north-south orientation. The area of southeastern New Mexico that falls between the mantle fast anomaly and the Great Plains craton displays dramatically smaller delay times, as well as changes in fast axis directions toward the northeast. Changes in fast axis directions may indicate flow around the mantle anomaly; small delay times could indicate vertical or attenuated flow.

  13. SAGE 2010 Magnetotelluric Soundings Provide New Constraints on Rio Grande Rift Mid-Crustal Conductor

    NASA Astrophysics Data System (ADS)

    Strader, A. E.; Martin, C. L.; Thomas, T.; Bedrosian, P. A.; Pellerin, L.; Jiracek, G. R.

    2010-12-01

    Since the inception of the Summer of Applied Geophysical Experience (SAGE) program in 1983, long-period magnetotelluric (MT) soundings have imaged a pronounced mid-crustal conductor at 10-20 km depth within the central Rio Grande rift. Wideband MT soundings (0.01 to over 1000 s period) collected in 2010 extended the detection of this feature to nearly 100 km length along the rift axis in the vicinity of Santa Fe, New Mexico. The conductive anomaly is clearly defined in the longest periods of the mode identified as the transverse electric (TE) in the recently acquired MT data. The spatially-limited 2010 soundings in the Santo Domingo Basin do not allow two-dimensional (2-D) inversions; however, one-dimensional (1-D) inversion of TE mode measurements in conductive rift basins can yield good depth estimates of deep conductive layers as has been shown by 2-D rift MT modeling. Such 1-D inversions of the 2010 MT soundings yield ~20 km depth to the top of the mid-crustal conductor, 5-10 km deeper than 90 km to the north if 3-D effects are negligible. Estimated conductance of the Santo Domingo basin conductor is 2000 S with resistivities in the range of 2-10 ohm-m. An interpretation of the ubiquitous, mid-crustal conductor in the Rio Grande rift is interconnected, saline, aqueous fluid trapped in the ductile crust below the ~10 km-deep seismogenic zone after fluid release and upward ascent from an upwarped mantle.

  14. Pathogenic Landscape of Transboundary Zoonotic Diseases in the Mexico–US Border Along the Rio Grande

    PubMed Central

    Esteve-Gassent, Maria Dolores; Pérez de León, Adalberto A.; Romero-Salas, Dora; Feria-Arroyo, Teresa P.; Patino, Ramiro; Castro-Arellano, Ivan; Gordillo-Pérez, Guadalupe; Auclair, Allan; Goolsby, John; Rodriguez-Vivas, Roger Ivan; Estrada-Franco, Jose Guillermo

    2014-01-01

    Transboundary zoonotic diseases, several of which are vector borne, can maintain a dynamic focus and have pathogens circulating in geographic regions encircling multiple geopolitical boundaries. Global change is intensifying transboundary problems, including the spatial variation of the risk and incidence of zoonotic diseases. The complexity of these challenges can be greater in areas where rivers delineate international boundaries and encompass transitions between ecozones. The Rio Grande serves as a natural border between the US State of Texas and the Mexican States of Chihuahua, Coahuila, Nuevo León, and Tamaulipas. Not only do millions of people live in this transboundary region, but also a substantial amount of goods and people pass through it everyday. Moreover, it occurs over a region that functions as a corridor for animal migrations, and thus links the Neotropic and Nearctic biogeographic zones, with the latter being a known foci of zoonotic diseases. However, the pathogenic landscape of important zoonotic diseases in the south Texas–Mexico transboundary region remains to be fully understood. An international perspective on the interplay between disease systems, ecosystem processes, land use, and human behaviors is applied here to analyze landscape and spatial features of Venezuelan equine encephalitis, Hantavirus disease, Lyme Borreliosis, Leptospirosis, Bartonellosis, Chagas disease, human Babesiosis, and Leishmaniasis. Surveillance systems following the One Health approach with a regional perspective will help identifying opportunities to mitigate the health burden of those diseases on human and animal populations. It is proposed that the Mexico–US border along the Rio Grande region be viewed as a continuum landscape where zoonotic pathogens circulate regardless of national borders. PMID:25453027

  15. Prevalence and Concomitants of Arthritis in the Elderly in Rio Grande do Sul, Brazil

    PubMed Central

    Blay, Sergio L.; Fillenbaum, Gerda G.; Andreoli, Sergio B.; Gastal, Fábio L.

    2012-01-01

    Objectives Information on the prevalence and concomitants of arthritis in developing countries is sparse. It is unclear whether they are comparable to findings in developed countries. To ascertain the prevalence, demographic characteristics, and health-related concomitants of arthritis in older persons in the southern state of Rio Grande do Sul, Brazil, a middle income country. Methods The state of Rio Grande do Sul, Brazil, was subdivided into nine regions. Stratified random sampling was used to identify 880 community residents age ≥60 years in each region. One region with suspect data was excluded. Of 7040 community residents contacted in eight regions, 6963 participated (1.1% refusal rate). In 1995, trained, monitored interviewers, using structured questionnaires, conducted in-home interviews gathering information on demographic characteristics (age, sex, race/ethnicity, education, income, living arrangements, employment status), health behaviors (physical activity, tobacco use, social activity), functional limitations, depression, and 15 self-reported health conditions, including arthritis. Data were analyzed using descriptive statistics and logistic regression. Results Arthritis, reported by 43% of the sample, was more prevalent in women, among the less educated, those with lower income, and higher age. Severity, but not prevalence, differed by race/ethnicity. Controlled analyses indicated significant association with female gender, lower education, and less social activity. Arthritis was associated with reduced odds of stroke, but increased odds of hypertension, varicosities, bronchitis, renal problems, headache, gastrointestinal disorders, and depression. Arthritis was not significantly associated with age or functional limitations, and associations did not differ by gender. Conclusions The prevalence, demographic and health characteristics associated with self-reported arthritis in this southern state in Brazil are similar to findings elsewhere in Brazil

  16. Molecular analysis of the iap gene of Listeria monocytogenes isolated from cheeses in rio grande do Sul, Brazil

    PubMed Central

    de Mello, Jozi Fagundes; Einsfeldt, Karen; Frazzon, Ana Paula Guedes; da Costa, Marisa; Frazzon, Jeverson

    2008-01-01

    The polymorphic region sequences in the iap gene were analyzed in 25 strains of Listeria monocytogenes isolated from cheeses in the state of Rio Grande do Sul, and compared with reference strains. This investigation distinguished two clusters of L. monocytogenes: I (20 strains) and II (5 strains). PMID:24031198

  17. 78 FR 16569 - Iowa Pacific Holdings, LLC, Permian Basin Railways, and San Luis & Rio Grande Railroad-Corporate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-15

    ... Holdings, LLC (IPH), its wholly owned subsidiaries Permian Basin Railways (PBR) and San Luis & Rio Grande..., IPH is a noncarrier that wholly owns PBR, which directly controls seven Class III railroads.\\1\\ PBR... (Saratoga). In addition, PBR controls 80% of Cape Rail, Inc. (Cape Rail), a noncarrier railroad...

  18. Sequence stratigraphic model of the Rio Grande Delta, south west Texas: Potential analog for the Niger Delta

    SciTech Connect

    Banfield, L.A.; Anderson, J.B.; Vail, P.R. )

    1996-01-01

    A sequence stratigraphic model developed from the ancient Rio Grande Delta in South West Texas is suggested as an analog for the Niger Delta. The two delta systems are characterized by high sand bedloads, shale diapirism with associated listric normal faulting, and large amounts of tidal and wave influence forming lower coastal plains characterized by swamps and estuaries. The sequence stratigraphic model of the ancient Rio Grande delta is based on approximately 1200 kilometers of single channel, 15 cubic inch water gun data, lithologic descriptions from approximately 25 long cores (28-30 m) located in 17-94 meters water depth, three gamma ray logs, paleontologic data from two cores, and oxygen isotopic data from one core (152 meters in length and located in 94 meters water depth). The combined data indicate that considerable quantities of sand are sequestered on the continental shelf and point sourcing the slope. The Rio Grande sequence stratigraphic model provides an improved understanding of sand deposits on the shelf, of the role of sediment bypass during lowstands, and of the base of slope deposits formed by headward eroding canyons ( ) or channels ( ) located at the shelf break. This information regarding the distribution of sand in the Rio Grande system can provide valuable insight into the reservoir distribution in the Niger system, improving existing reservoir predictions.

  19. Binational Dilemmas: the Contrasting Challenges for Environmental Management and Restoration of the Colorado River and Rio Grande

    NASA Astrophysics Data System (ADS)

    Schmidt, J. C.; Wilcock, P. R.

    2006-12-01

    The United States and Mexico share waters of the Colorado River and Rio Grande. The two countries have signed joint declarations and begun talks focused on rehabilitating parts of these rivers affected by upstream dams and diversions. These areas include the Colorado River Delta and the Rio Grande downstream from Fort Quitman, TX. Other parts of these river systems are the focus on single country restoration efforts, such as the Glen Canyon Dam Adaptive Management Program and the effort to recover the Rio Grande silvery minnow. Regional and international coordination and collaboration are needed to focus limited restoration funds toward their most beneficial use. Analysis of historical records, published studies of channel change, and computation of sediment mass balance conditions demonstrates that the challenges and difficulties of rehabilitating different parts of the Colorado River and Rio Grande vary greatly. There is little accordance between the importance and tractability of restoration opportunities and the magnitude and location of investment in these opportunities. In some cases, large river management problems are focused on relatively intractable problems, while elsewhere relatively modest and solvable problems are ignored. We demonstrate how watershed scale analysis of the magnitude of hydrologic and geomorphic perturbations and the costs of addressing these perturbations can help guide the allocation of limited public resources to best meet the challenges faced by Mexico and the United States in rehabilitating its shared rivers.

  20. Sequence stratigraphic model of the Rio Grande Delta, south west Texas: Potential analog for the Niger Delta

    SciTech Connect

    Banfield, L.A.; Anderson, J.B.; Vail, P.R.

    1996-12-31

    A sequence stratigraphic model developed from the ancient Rio Grande Delta in South West Texas is suggested as an analog for the Niger Delta. The two delta systems are characterized by high sand bedloads, shale diapirism with associated listric normal faulting, and large amounts of tidal and wave influence forming lower coastal plains characterized by swamps and estuaries. The sequence stratigraphic model of the ancient Rio Grande delta is based on approximately 1200 kilometers of single channel, 15 cubic inch water gun data, lithologic descriptions from approximately 25 long cores (28-30 m) located in 17-94 meters water depth, three gamma ray logs, paleontologic data from two cores, and oxygen isotopic data from one core (152 meters in length and located in 94 meters water depth). The combined data indicate that considerable quantities of sand are sequestered on the continental shelf and point sourcing the slope. The Rio Grande sequence stratigraphic model provides an improved understanding of sand deposits on the shelf, of the role of sediment bypass during lowstands, and of the base of slope deposits formed by headward eroding canyons (?) or channels (?) located at the shelf break. This information regarding the distribution of sand in the Rio Grande system can provide valuable insight into the reservoir distribution in the Niger system, improving existing reservoir predictions.

  1. Release and recovery of exotic parasitoids of Bemisia tabaci in the Lower Rio Grande Valley of Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An intensive field program was conducted in the subtropical Lower Rio Grande Valley of Texas (LRGV) to evaluate the establishment of the imported parasitoids of B. tabaci. Thirty populations/species of Eretmocerus and Encarsia parasitoids were mass reared for field release in multiple agricultural c...

  2. Mexican Migrations to the U.S., 1900-1920, with a Focus on the Texas Lower Rio Grande Valley.

    ERIC Educational Resources Information Center

    Miller, Hubert J.

    Migrations from 1900-1920 were analyzed, focusing on the overall pattern of Mexican migrations to the United States during the two decades; migrations to Texas, the major recipient of migrants during the period; and migrations into the lower Rio Grande Valley. Data were based on official registrations either entering the United States or leaving…

  3. 78 FR 1763 - Oranges and Grapefruit Grown in Lower Rio Grande Valley in Texas; Increased Assessment Rate

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-09

    ...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 906 Oranges and Grapefruit Grown in Lower Rio Grande Valley in Texas; Increased Assessment Rate AGENCY: Agricultural Marketing Service, USDA... Valley in Texas, hereinafter referred to as the ``order.'' The order is effective under the...

  4. DIETARY CHARACTERIZATIONS IN A STUDY OF HUMAN EXPOSURES IN THE LOWER RIO GRANDE VALLEY:II. HOUSEHOLD WATERS

    EPA Science Inventory

    The Lower Rio Grande Valley Environmental Study (LRGVES) was designed to evaluate multiple forms of exposure to Valley residents because of community concerns of possible adverse health effects from environmental conditions. This is the second of two papers that describe the diet...

  5. School and Public Youth Librarians as Health Information Gatekeepers: Research from the Lower Rio Grande Valley of Texas

    ERIC Educational Resources Information Center

    Lukenbill, Bill; Immroth, Barbara

    2009-01-01

    This study investigated how school and public librarians can become better disseminators of health information and improve health information literacy in small and rural communities in a selected research area. We used the Lower Rio Grande Valley of Texas as our study area, composed of the economically depressed Cameron, Hidalgo, Starr, and…

  6. Susceptibility of redbanded and conchuela stink bugs from the Texas Lower Rio Grande Valley to organophosphate and pyrethroid insecticides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report the susceptibility of 2 stink bug species, red banded stink bug (RBSB), Piezodorus guildinii, (Westwood) and conchuela stinkbug, Chlorochroa ligata (Say) collected in the Texas Lower Rio Grande Valley to selected pyrethroid and organophosphate technical grade insecticides. The adult glass ...

  7. IRRIGATION RETURN FLOW WATER QUALITY MONITORING, MODELING AND VARIABILITY IN THE MIDDLE RIO GRANDE VALLEY, NEW MEXICO

    EPA Science Inventory

    A 250-acre (100 hectare) irrigated farm in the middle Rio Grande valley at San Acacia, New Mexico, was intensively monitored for the five year period from 1977 through 1982. During that time there was no statistically significant change in the total dissolved solids concentration...

  8. SOCIO-ECONOMIC AND INSTITUTIONAL FACTORS IN IRRIGATION RETURN FLOW QUALITY CONTROL. VOLUME III. MIDDLE RIO GRANDE VALLEY CASE STUDY

    EPA Science Inventory

    Degradation of water quality as a consequence of use in irrigation in the Lower Rio Grande Valley of New Mexico is a largely unavoidable phenomenon. In this region annual allocations of water to irrigated farms, about 2.5 acre-feet per acre, are little more than enough to produce...

  9. 76 FR 21855 - Rio Grande National Forest, Divide Ranger District; Mineral County, CO; Village at Wolf Creek...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-19

    ... Forest Service Rio Grande National Forest, Divide Ranger District; Mineral County, CO; Village at Wolf... totaling approximately 204 acres. The non-Federal parcel is located in T37N., R2E., NMPM, Mineral County..., Mineral County, CO, Sections 3, 4, 5, and 9. DATES: Formal scoping on this project begins on April...

  10. Mapping giant reed (Arundo donax) infestations along the Texas-Mexico portion of the Rio Grande using aerial photography

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Giant reed is an invasive weed throughout the southern half of the United States with the densest stands growing along the coastal rivers of southern California and the Rio Grande in Texas. The objective of this study was to use aerial photography to map giant reed infestations and estimate infested...

  11. Using aerial photography for mapping giant reed infestations along the Texas-Mexico portion of the Rio Grande.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Giant reed (Arundo donax L.) is an invasive weed throughout the southern half of the United States with the densest stands growing along the coastal rivers of southern California and the Rio Grande in Texas. The objective of this study was to use aerial photography to map giant reed infestations and...

  12. Assessing climate change impacts on water availability of snowmelt-dominated basins of the Upper Rio Grande Basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Study Region- Upper Rio Grande, Colorado and New Mexico, USA: Climate change is predicted to further limit the water availability of the arid southwestern U.S. In this study, the Snowmelt Runoff Model is used to evaluate impacts of increased temperature and altered precipitation on snow covered are...

  13. Using QuickBird satellite imagery to estimate giant reed infestations in the Rio Grande Basin of Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Giant reed (Arundo donax L.) is a perennial invasive weed that presents a severe threat to agroecosystems and riparian areas in the Texas and Mexican portions of the Rio Grande Basin. The objective of this study was to use QuickBird satellite imagery to map giant reed infestations and estimate infes...

  14. Herpetofauna of Núcleo Experimental de Iguaba Grande, Rio de Janeiro state, Brazil.

    PubMed

    Martins, A R; Bruno, S F; Navegantes, A Q

    2012-08-01

    The Atlantic Rain forest, which is considered the second largest pluvial forest in the American continent, has had an estimated 93% of its original area destroyed. Although studies concerning the herpetofaunal diversity in this biome have been intensified in the past years, its diversity is still underestimated. The Nucleo Experimental de Iguaba Grande (NEIG) is included in an Environmental Protection Area (APA de Sapeatiba) in the Iguaba Grande municipality, Rio de Janeiro state, Brazil (22º 51' S and 42º 10' W). The goal of this study was to conduct an inventory of the reptile and amphibian species that occur in this area between July 2008 and December 2009. We recorded 19 species of amphibians (18 anurans and one caecilian) and 15 species of reptiles (three lizards, 11 snakes and one amphisbaenian). Leptodactylus latrans and L. mystacinus had the highest capture rates among amphibians captured, and among reptiles, Ameiva ameiva, Hemidactylus mabouia and Mabuya agilis had the highest capture rates. Rarefaction curves for both amphibians and reptiles did not reach the asymptote, indicating that the species richness in the NEIG is still underestimated. PMID:22990826

  15. Population data of 17 Y-STR loci from Rio Grande do Sul state (South Brazil).

    PubMed

    Schwengber, Solange P; Kommers, Trícia; Matte, Cecília H F; Raimann, Paulo E; Carvalho, Bianca A; Leite, Fabio P N; Medeiros, Marcelo A; Souza, Luis F; Castro, Cibele S; Chassot, Fernanda G C; Bonatto, Sandro L

    2009-12-01

    A sample of 255 Brazilian males from Rio Grande do Sul (RS), the Brazilian southernmost state, was typed for 17 Y-STR loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, YGATA_H4.1 and DYS385ab). A total of 247 haplotypes were identified, of which 239 were unique and eight were found in two individuals each. The haplotype diversity (99.98%) and discrimination capacity (96.86%) were calculated. Pairwise haplotype distances showed that the RS population is not significantly different from Brazil, Rio de Janeiro, and Argentina, is different from São Paulo, Italy, and North Portugal, and is very distant from Spain, the Amazon region, Germany, and South Amerindians. When the RS data was separated in the seven geopolitical regions, some pairs of regions were significantly different; however no region was different from the whole Brazilian sample. PMID:19948319

  16. Quantifying Saline Groundwater Discharge to the Rio Grande using 87Sr/86Sr and [Ca]/[Sr] Ratios

    NASA Astrophysics Data System (ADS)

    Hogan, J. F.; Phillips, F. M.; Mills, S. K.; Ruiz, J.; Chesley, J. T.

    2002-12-01

    Issues of water quality, especially salinity, limit the use of water resources from the Rio Grande. Identification and quantification of salinity sources is critical for improved river management. We have conducted winter and summer synoptic sampling of the Rio Grande from the headwaters in Colorado to south of El Paso, Texas. The total dissolved solids content (TDS) of the Rio Grande increases from less than 50 mg/L in headwater regions of Colorado to greater than 2000 mg/L south of El Paso, Texas. Increases in salinity are not a simple function of distance downriver, but rather occur in a series of steps. Many of these increases are located at the lower end of sedimentary basins leading to the hypothesis that they are the result of discharge of deep, saline, groundwaters. Of particular interest is the Albuquerque and Socorro basins where, in three distinct steps, the TDS of the river doubles from ~ 150 mg/L to ~ 300 mg/L. With little change in river discharge for this reach, this represents a significant increase in the solute burden of the river. We have used 87Sr/86Sr and [Ca]/[Sr] ratios to "fingerprint" and quantify saline groundwater discharge. The Rio Grande entering the Albuquerque basin has an 87Sr/86Sr ratio of 0.7096and a [Ca]/[Sr] ratio of 80. These values are consistent with a mixture of atmospheric deposition and weathering of basalt rock found upstream. Traveling through the Albuquerque and Socorro basin the Rio Grande shifts to a 87Sr/86Sr ratio of 0.7102 and a [Ca]/[Sr] ratio of 30, values which are consistent with saline groundwater discharge. Mixing relationships indicate only two solute sources are required, and that a total saline groundwater discharge rate of ~ 50 cfs is sufficient to explain the observed salinity increases.

  17. Reconnaissance for uranium in the coal of Sao Paulo, Santa Catarina, and Rio Grande do Sul, Brazil

    USGS Publications Warehouse

    Haynes, Donald D.; Pierson, Charles T.; White, Max G.

    1958-01-01

    Uranium-bearing coal and carbonaceous shale of the Rio Bonito formation of Pennsylvanian age have been found in the States of Sao Paulo, Santa Catarlna and Rio Grande do Sul, Brazil. The uranium oxide content of the samples collected in the State of Sao Paulo ranges from 0.001 percent to 0.082 percent. The samples collected in Santa Catarina averaged about 0.002 percent uranium oxide; those collected in Rio Grande do Sul, about 0.003 percent uranium oxide. Since the field and laboratory investigations are still in their initial stages, only raw data on the radioactivity and uranium content of Brazilian coals are given in this report.

  18. The Role of Climatic Variability on Rio Grande Salinity and Water Balances

    NASA Astrophysics Data System (ADS)

    Hogan, J. F.; Phillips, F. M.

    2008-12-01

    The upper Rio Grande/ Rio Bravo extends ~1,200 km between its headwaters in southern Colorado (USA) and the USA/Mexico border region. Like many arid region rivers, it exhibits reductions in streamflow and degrading water quality with distance downstream as a result of decreasing inflows, increasing evapotranspiration, and the addition of natural and anthropogenic solutes. From 2000 to 2007 we conducted detailed biannual synoptic sampling of the Rio Grande from its headwaters in Colorado to ~150 km south of El Paso, Texas to evaluate how these processes result in the observed basin-scale water and solute balances. This period coincides with a severe regional drought, as well as the 8th wettest summer monsoon in the region, allowing us to assess how basin processes which control water quality respond to periods of climatic variability. We employed multiple environmental tracers to help identify dominant hydrological processes and the causes of salinization. Our O and H isotopic results indicate that runoff from high-elevation areas in Colorado and northern New Mexico - primarily as snowmelt - is the dominant source of river water, although runoff from summer precipitation can be locally and seasonally significant. This water then exhibits progressive evaporation with distance downstream, with the greatest evaporation occurring at Elephant Butte Reservoir. At the same time, the total dissolved solids content (TDS) increases from less than 50 mg/L in headwaters of Colorado to over 2000 mg/L south of El Paso, Texas. Water balance estimates and our O and H isotope results indicate that evapotranspiration alone is not sufficient to explain the salinization. The results of our synoptic surveys found that salinity did not increase as a simple function of distance downriver but rather occurred in a series of steps, identified as discharge of deep, saline, ground water. During the course of the drought we observed a progressive increase in salt concentrations and more

  19. Mantle water contents beneath the Rio Grande Rift (NM, USA): FTIR analysis of Rio Puerco and Kilbourne Hole peridotite xenoliths

    NASA Astrophysics Data System (ADS)

    Schaffer, L. A.; Peslier, A. H.; Brandon, A. D.; Selverstone, J.

    2015-12-01

    Peridotite xenoliths from the Rio Grande Rift (RGR) are being analyzed for H2O contents by FTIR as well as for major and trace element compositions. Nine samples are from the Rio Puerco Volcanic Field (RP) which overlaps the central RGR and southeastern Colorado Plateau; seventeen samples are from Kilbourne Hole (KH) in the southern RGR. Spinel Cr# (Cr/(Cr+Al) = 0.08-0.46) and olivine Mg# (Mg/(Mg+Fe) = 0.883-0.911) of samples fall within the olivine-spinel mantle array from [1], an indicator that these are residues of partial melting. Pyroxene H2O contents in KH correlate with bulk rock and pyroxene Al2O3 contents. The KH clinopyroxene rare earth element (REE) variations fit models of 0-13% fractional melting of a primitive upper mantle. Most KH peridotites have bulk-rock light REE depleted patterns, but five are enriched in light REEs consistent with metasomatism. Variation in H2O content seems unrelated to REE enrichment. Metasomatism is seen in RP pyroxenite xenoliths [2] and will be examined in the peridotites studied here. Olivine H2O contents are low (≤20 ppm), and decrease from core to rim within grains. This is likely due to H loss during xenolith transport by the host magma [3]. Diffusion models of H suggest that mantle H2O contents are still preserved in cores of KH olivine, but not those of RP olivine. The average H2O content of Colorado Plateau clinopyroxene (670 ppm) [4] is ~300 ppm higher than RGR clinopyroxene (350 ppm). This upholds the hypothesis that hydration-induced lithospheric melting occurred during flat-slab subduction of the Farallon plate [5]. Numerical models indicate hydration via slab fluids is possible beneath the plateau, ~600 km from the paleo-trench, but less likely ~850 km away beneath the rift [6]. [1]Arai, 1994 CG 113, 191-204.[2]Porreca et al., 2006 Geosp 2, 333-351.[3]Peslier and Luhr, 2006 EPSL 242, 302-319.[4]Li et al., 2008 JGR 113, 1978-2012.[5]Humphreys et al., 2003 Int Geol Rev 45, 575-595.[6]English et al., 2003 EPSL

  20. Mantle Water Contents Beneath the Rio Grande Rift (NM, USA): FTIR Analysis of Rio Puerco and Kilbourne Hole Peridotite Xenoliths

    NASA Technical Reports Server (NTRS)

    Schaffer, L. A.; Peslier, A. H.; Brandon, A.; Selverstone, J.

    2015-01-01

    Peridotite xenoliths from the Rio Grande Rift (RGR) are being analyzed for H (sub 2) O contents by FTIR (Fourier Transform Infrared) as well as for major and trace element compositions. Nine samples are from the Rio Puerco Volcanic Field (RP) which overlaps the central RGR and southeastern Colorado Plateau; seventeen samples are from Kilbourne Hole (KH) in the southern RGR. Spinel Cr# (Cr/(Cr+Al)) (0.08-0.46) and olivine Mg# (Mg/(Mg plus Fe)) (0.883-0.911) of all RGR samples fall within the olivine-spinel mantle array from [1], an indicator that peridotites are residues of partial melting. Pyroxene H (sub 2) O in KH correlate with bulk rock and pyroxene Al (sub 2) O (sub 3).The KH clinopyroxene rare earth element (REE) variations fit models of 0-13 percent fractional melting of a primitive upper mantle. Most KH peridotites have bulk-rock light REE depleted patterns, but five are enriched in light REEs consistent with metasomatism. Variation in H (sub 2) O content is unrelated to REE enrichment. Metasomatism is seen in RP pyroxenite xenoliths [2] and will be examined in the peridotites studied here. Olivine H (sub 2) O contents are low (less than or equal to 15 parts per million), and decrease from core to rim within grains. This is likely due to H loss during xenolith transport by the host magma [3]. Diffusion models of H suggest that mantle H (sub 2) O contents are still preserved in cores of KH olivine, but not RP olivine. The average H (sub 2) O content of Colorado Plateau clinopyroxene (670 parts per million) [4] is approximately 300 parts per million higher than RGR clinopyroxene (350 parts per million). This upholds the hypothesis that hydration-induced lithospheric melting occurred during flat-slab subduction of the Farallon plate [5]. Numerical models indicate hydration via slab fluids is possible beneath the plateau, approximately 600 kilometers from the paleo-trench, but less likely approximately 850 kilometers away beneath the rift [6].

  1. Hydrochemical tracers in the middle Rio Grande Basin, USA: 1. Conceptualization of groundwater flow

    NASA Astrophysics Data System (ADS)

    Plummer, L. Niel; Bexfield, Laura M.; Anderholm, Scott K.; Sanford, Ward E.; Busenberg, Eurybiades

    Chemical and isotopic data for groundwater from throughout the Middle Rio Grande Basin, central New Mexico, USA, were used to identify and map groundwater flow from 12 sources of water to the basin, evaluate radiocarbon ages, and refine the conceptual model of the Santa Fe Group aquifer system. Hydrochemical zones, representing groundwater flow over thousands to tens of thousands of years, can be traced over large distances through the primarily siliciclastic aquifer system. The locations of the hydrochemical zones mostly reflect the ``modern'' predevelopment hydraulic-head distribution, but are inconsistent with a trough in predevelopment water levels in the west-central part of the basin, indicating that this trough is a transient rather than a long-term feature of the aquifer system. Radiocarbon ages adjusted for geochemical reactions, mixing, and evapotranspiration/dilution processes in the aquifer system were nearly identical to the unadjusted radiocarbon ages, and ranged from modern to more than 30 ka. Age gradients from piezometer nests ranged from 0.1 to 2 year cm-1 and indicate a recharge rate of about 3 cm year-1 for recharge along the eastern mountain front and infiltration from the Rio Grande near Albuquerque. There has been appreciably less recharge along the eastern mountain front north and south of Albuquerque. Des données sur les éléments chimiques et les isotopes présents dans l'eau souterraine prélevée à divers endroits dans le bassin moyen du Rio Grande, au centre du Nouveau-Mexique (É-U), ont permis de déterminer l'existence et l'étendue de douze sources d'eau régionales dans le bassin, d'évaluer les âges radiocarbones et de raffiner le modèle conceptuel du système aquifère du groupe de Santa Fe. Des zones hydro-chimiques qui représentent l'écoulement de l'eau souterraine depuis des dizaines de milliers d'années peuvent être suivies sur de longues distances à travers l'aquifère principalement siliclastique. La position des

  2. Species richness, relative abundance, and habitat associations of nocturnal birds along the rio grande in Southern texas

    USGS Publications Warehouse

    Skoruppa, M.K.; Woodin, M.C.; Blacklock, G.

    2009-01-01

    The segment of the Rio Grande between International Falcon Reservoir and Del Rio, Texas (distance ca. 350 km), remains largely unexplored ornithologically. We surveyed nocturnal birds monthly during February-June 1998 at 19 stations along the Rio Grande (n = 6) and at upland stock ponds (n = 13) in Webb County, Texas. We conducted 10-min point counts (n = 89) after sunset and before moonset. Four species of owls and five species of nightjars were detected. Nightjars, as a group, were nearly five limes more abundant (mean number/count = 2.63) than owls (mean number = 0.55). The most, common owl, the great horned owl (Bubo virginianus), had a mean number of 0.25/point count. The mean for elf owls (Micrathene whitneyi) was 0.16/point count. The most common nightjars were the common poorwill (Phalaenoptilus nuttallii; 1.21/point count) and lesser nighthawk (Chordeiles acutipennir, 1.16/point count). Survey sites on the river supported more species (mean = 2.2) than did upland stock ponds (mean = 1.4). However, only one species (common pauraque, Nyctidromus albicollis) showed a preference for the river sites. Our results establish this segment of the Rio Grande in southern Texas as an area of high diversity of nightjars in the United States, matched (in numbers of species) only by southeastern Arizona and southwestern New Mexico.

  3. Biomarkers of exposure and effects of environmental contaminants on swallows nesting along the Rio Grande, Texas, USA

    USGS Publications Warehouse

    Mora, M.A.; Musquiz, D.; Bickham, J.W.; MacKenzie, D.S.; Hooper, M.J.; Szabo, J.K.; Matson, C.W.

    2006-01-01

    We collected adult cave swallows (Petrochelidon fulva) and cliff swallows (P. pyrrhonota) during the breeding seasons in 1999 and 2000 from eight locations along the Rio Grande from Brownsville to El Paso (unless otherwise specified, all locations are Texas, USA) and an out-of-basin reference location. Body mass, spleen mass, hepatosomatic index (HSI), gonadosomatic index (GSI), thyroxine (T4) in plasma, DNA damage measured as the half-peak coefficient of variation of DNA content (HPCV) in blood cells, as well as acetylcholinesterase and butyrylcholinesterase in brain were compared with concentrations of organochlorines, metals, and metalloids in carcasses to determine potential effects of contaminants on swallows during the breeding season. Concentrations of 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p???-DDE) were significantly greater in swallows from El Paso than in those from most locations, except for Pharr and Llano Grande. All swallows from these three locations had p,p???-DDE concentrations of 3 ??g/g wet weight or greater. Swallows from El Paso either had or shared the highest concentrations of p,p???-DDE, polychlorinated biphenyls, and 13 inorganic elements. Swallows from El Paso exhibited greater spleen mass and HPCV values as well as lower T4 values compared with those from other locations. Thyroxine was a potential biomarker of contaminant exposure in swallows of the Rio Grande, because it was negatively correlated with p,p???-DDE and Se. Spleen mass was positively correlated with selenium and HSI and negatively correlated with body mass, GSI, Mn, and Ni. Overall, the present study suggests that insectivorous birds living in areas of high agricultural and industrial activity along the Rio Grande bioaccumulate environmental contaminants. These contaminants, particularly p,p???-DDE, may be among multiple factors that impact endocrine and hematopoietic function in Rio Grande swallows. ?? 2006 SETAC.

  4. Paleomagnetism and Tectonic Interpretations of the Taos Plateau Volcanic Field, Rio Grande Rift, New Mexico

    NASA Technical Reports Server (NTRS)

    Brown, Laurie L.; Caffall, Nancy M.; Golombek, Matthew P.

    1993-01-01

    The tectonic response of the Taos Plateau volcanic field in the southern San Luis basin to the late stage extensional environment of the Rio Grande rift was investigated using paleomagnetic techniques. Sixty-two sites (533 samples) of Pliocene volcanic units were collected covering four major rock types with ages of 4.7 to 1.8 Ma. Twenty-two of these sites were from stratigraphic sections of the lower, middle and upper Servilleta Basalt collected in the Rio Grande gorge at two locations 19 km apart. Flows from the lower and middle members in the southern gorge record reversed polarities, while those in Garapata Canyon are normal with an excursion event in the middle of the sequence. The uppermost flows of the upper member at both sites display normal directions. Although these sections correlate chemically, they seem to represent different magnetic time periods during the Gilbert Reversed-Polarity Chiron. Alternating field demagnetization, aided by principal component analysis, yields 55 sites with stable directions representing both normal and reversed polarities, and five sites indicating transitional fields. Mean direction of the normal and inverted reversed sites is I=49.3 deg. and D=356.7 deg. (alpha(sub 95)=3.6 deg). Angular dispersion of the virtual geomagnetic poles is 16.3 deg, which is consistent with paleosecular variation model G, fit to data from the past 5 m.y. Comparison with the expected direction indicates no azimuthal rotation of the Taos Plateau volcanic field; inclination flattening for the southern part of the plateau is 8.3 deg +/- 5.3 deg. Previous paleomagnelic data indicate 10 deg- 15 deg counterclockwise rotation of die Espanola block to the south over the past 5 m.y. The data suggest the Taos Plateau volcanic field, showing no rotation and some flattening in the south and east, has acted as a stable buttress and has been downwarped by overriding of the southeastern end of the plateau by the Picuris Mountains, which make up the northern

  5. An Integrated Model for a Water Leasing System on the Middle Rio Grand, New Mexico

    NASA Astrophysics Data System (ADS)

    Brookshire, D. S.; Coursey, D. L.; Tidwell, V. C.; Broadbent, C. D.

    2006-12-01

    Since 1950 demand for water has more than doubled in the United States. Virtually all water supplies are allocated, leading to the question, where will water come from? The concept of water leasing has gained considerable attention as a volunteer, market-mediated system for transferring water between competing uses. For a water leasing system to be truly effective, detailed knowledge of the available water supply and the factors that affect water demand is critical. Improving understating of the factors that determine residential, industrial, and agricultural demand for water using experimental economics and then integrating with a hydrological model will allow for better understanding of market-based mechanisms potential to allocate water resources effectively. Currently we have three case studies underway, a generalized water leasing system on the Middle Rio Grande, a sophisticated farmer decision process and a study in the Mimbres basin in southern New Mexico. The developed market model utilizes an open market trading system known as a double auction, where buyers and sellers declare their bids and offers to the market. The developed hydrological model utilizes the Upper Rio Grande Water Operations Model (URGWOM) system structure and data for the generalized water leasing system and the farmer decision process, with a different hydrological model being developed for the Mimbres basin. A key coupling between the hydrologic and market models involves tracking the difference in river losses for trades that move water up or down the river. In the experiments the hydrological model runs before the market-trading period to establish water rights, the trading period occurs and the hydrological model then runs a second time to report flows to each reach of the river. Participants in the experiment represent the interests of specific users, including farmers, Native American interests, urban interests and environmental interests. Participants in the experiments are

  6. Data collection for cooperative water resources modeling in the Lower Rio Grande Basin, Fort Quitman to the Gulf of Mexico.

    SciTech Connect

    Passell, Howard David; Pallachula, Kiran; Tidwell, Vincent Carroll; Villalobos, Joshua; Piccinni, Giovanni; Brainard, James Robert; Gerik, Thomas; Morrison, Wendy; Serrat-Capdevila, Aleix; Valdes, Juan; Sheng, Zhuping; Lovato, Rene; Guitron, Alberto; Ennis, Martha Lee; Aparicio, Javier; Newman, Gretchen Carr; Michelsen, Ari M.

    2004-10-01

    Water resource scarcity around the world is driving the need for the development of simulation models that can assist in water resources management. Transboundary water resources are receiving special attention because of the potential for conflict over scarce shared water resources. The Rio Grande/Rio Bravo along the U.S./Mexican border is an example of a scarce, transboundary water resource over which conflict has already begun. The data collection and modeling effort described in this report aims at developing methods for international collaboration, data collection, data integration and modeling for simulating geographically large and diverse international watersheds, with a special focus on the Rio Grande/Rio Bravo. This report describes the basin, and the data collected. This data collection effort was spatially aggregated across five reaches consisting of Fort Quitman to Presidio, the Rio Conchos, Presidio to Amistad Dam, Amistad Dam to Falcon Dam, and Falcon Dam to the Gulf of Mexico. This report represents a nine-month effort made in FY04, during which time the model was not completed.

  7. Significant cenozoic faulting, east margin of the Espanola basin, Rio Grande Rift, New Mexico

    SciTech Connect

    Vernon, J.H. ); Riecker, R.E.

    1989-03-01

    Tectonic interpretation of the east margin of the Espanola Basin, Rio Grande rift, New Mexico, has been controversial. Previous authors have disagreed as to whether significant faulting defines the boundary between the basin and the Sangre de Cristo Mountains. A more recent geophysical basin transect that suggests no significant faulting and field observation of faceted spurs along the western Sangre de Cristo Mountain front indicating a faulted margin motivate our study. The east margin of the Espanola Basin for about 37 km north of Santa Fe, New Mexico, is marked by a complex array of significant, late Cenozoic high-angle faults. Locally, three parallel, north-trending, high-angle faults cut Precambrian basement and Tertiary basin-full rocks along the basin margin. Elsewhere along the margin, tilted fault blocks and intersecting faults occur. Fault area, fault attitude with depth, magnitude of fault motion, and timing of fault motion remain uncertain. However, faults studied in detail are 1-2 km long, have minimum dip-slip motion of 33-100 m, and underwent movement during the late Cenozoic. Potentially significant tectonic and seismic hazard implications arise from the possibility of post-150 ka fault motion.

  8. Synoptic Sampling of Dissolved Nitrogen Species and Organic Carbon in the Rio Grande Basin

    NASA Astrophysics Data System (ADS)

    Villinski, J. E.; Hogan, J. F.; Brooks, P. D.; Haas, P. A.; Mills, S. K.

    2002-12-01

    Synoptic sampling has been performed along the Rio Grande from the headwaters in Colorado to Fort Quitman, Texas, south of El Paso. Samples from August 2001 and January 2002 were analyzed for nitrate (NO3-), ammonium (NH_{4}$+), total dissolved nitrogen (TDN), and dissolved organic carbon (DOC). DOC concentrations increase slowly between Colorado and southern New Mexico and then approximately double in Texas. Large sources of N during both sampling periods were the urban areas around Albuquerque and El Paso, Texas and Ciudad Juarez, Mexico, and agricultural regions in the Rincon and Mesilla valleys of southern New Mexico. Nitrate-N concentrations remained high south of Albuquerque to Elephant Butte reservoir in the summer, presumably due to lack of primary production. Inorganic N concentrations generally are higher in the winter than in the summer. During the summer, ammonium concentrations were greater than 100 mg N/l only at the outlet of Elephant Butte Reservoir, and in Texas. However, winter concentrations were on average an order of magnitude greater, again with the largest ammonium values (5000 \\mug N/l) in Texas. These patterns are consistent with a reduction in biological nutrient demand during the non-growing season.

  9. Synthesis of benthic flux components in the Patos Lagoon coastal zone, Rio Grande do Sul, Brazil

    NASA Astrophysics Data System (ADS)

    King, J. N.

    2012-12-01

    The primary objective of this work is to synthesize components of benthic flux in the Patos Lagoon coastal zone, Rio Grande do Sul, Brazil. Specifically, the component of benthic discharge flux forced by the terrestrial hydraulic gradient is 0.8 m3 d-1; components of benthic discharge and recharge flux associated with the groundwater tidal prism are both 2.1 m3 d-1; components of benthic discharge and recharge flux forced by surface-gravity wave setup are both 6.3 m3 d-1; the component of benthic discharge flux that transports radium-228 is 350 m3 d-1; and components of benthic discharge and recharge flux forced by surface-gravity waves propagating over a porous medium are both 1400 m3 d-1. (All models are normalized per meter shoreline.) Benthic flux is a function of components forced by individual mechanisms and nonlinear interactions that exist between components. Constructive and destructive interference may enhance or diminish the contribution of benthic flux components. It may not be possible to model benthic flux by summing component magnitudes. Geochemical tracer techniques may not accurately model benthic discharge flux or submarine groundwater discharge (SGD). A conceptual model provides a framework on which to quantitatively characterize benthic discharge flux and SGD with a multifaceted approach.

  10. Anticholinesterase exposure of white-winged doves breeding in lower Rio Grande valley, Texas

    USGS Publications Warehouse

    Tacha, T.C.; Schacht, S.J.; George, R.R.; Hill, E.F.

    1994-01-01

    We studied exposure of breeding white-winged doves (Zenaida asiatica) to anticholinesterase compounds (organophosphorus and carbamate pesticides) in the Lower Rio Grande Valley (LRGV), Texas. Widespread use of organophosphorus pesticides and dove population declines prompted the study. We collected breeding adult doves in May and July 1991 (n = 28) and July 1992 (n = 33) at 6 locations. We used depression of whole-brain cholinesterase (ChE) activity (2 SD below control mean) to detect exposure; values from 4 hand-reared doves fed commercial pigeon chow served as the control. Mean brain ChE activity was lower (P lt 0.027) than the control sample at all 6 locations in 1991; 79% of the birds were diagnostic of exposure ( gt 16.1% ChE depression). Pooled 1992 field samples also were lower (P lt 0.036) than were control samples; doves from 4 of the 6 locations had brain ChE activity below (P lt 0.088) controls. Overall, 39% of 1992 doves were diagnostic of exposure to anticholinesterase compounds. Higher exposure rates in 1991 were probably due to increased use of organophosphorus pesticides. Research is needed documenting effects of sublethal exposure on white-winged dove productivity.

  11. Prevalence of acanthamoeba from tap water in rio grande do Sul, Brazil.

    PubMed

    Winck, Mari Aline Todero; Caumo, Karin; Rott, Marilise Brittes

    2011-11-01

    A total of 136 samples of tap water were collected from state and municipal schools between March and November 2009. The samples were filtered through cellulose nitrate membranes that were seeded at non-nutrient agar 1.5% containing an overlayer of Escherichia coli suspension. Thirty-one (22.79%) tap water samples investigated were found positive for free-living amoebae (FLA). From these, 13 presented as FLA that seems to belong to the genus Acanthamoeba. All samples of FLA were cloned and identified as belonging to the genus Acanthamoeba by the morphology of cysts and trophozoites and by PCR using genus-specific primers that amplify the ASA.S1 region of 18S rDNA gene. Physiological tests of thermotolerance and osmotolerance were used to evaluate the pathogenicity of the isolates. The sequencing analysis by comparing the sequences submitted to GenBank, showed genotype distribution into groups T2, T2/T6, T6, and T4. In tests of thermotolerance and osmotolerance, 50% of the isolates had a low pathogenic potential. The results indicated the presence of Acanthamoeba in tap water in Rio Grande do Sul, Brazil, revealing its importance and the need for more epidemiological studies to determine their distribution in the environment and its pathogenic potential. PMID:21882008

  12. The Clyde W. Tombaugh Papers and the Rio Grande Historical Collections: Preserving the History of Astronomy

    NASA Astrophysics Data System (ADS)

    Gottwald, M.

    2003-12-01

    The study of the history of astronomy requires not only dedicated researchers, but also source material. This requires archives and libraries that are actively involved in preserving astronomy-related collections. It is also vitally important that astronomers and astronomy associations make the effort to deposit their papers in these institutions. One repository with a growing body of astronomy-related holdings is the Rio Grande Historical Collections (RGHC) in the New Mexico State University Library. This paper considers, from an archival perspective, some of the issues of making astronomy-related collections available. Depositing the historical papers in the archives is only the beginning of the process; the archives must also arrange the materials and prepare descriptions that will facilitate research use. The astronomy collections in the RGHC are discussed, with particular focus on the Clyde W. Tombaugh Papers. The Tombaugh Papers presented special challenges in part because of the size of the collection and the numerous types of materials. Additional issues involved Tombaugh's long and varied career which included not only the planet search at Lowell Observatory but also his work in optics at the U.S. Army's White Sands Proving Ground and the establishment of the Department of Astronomy at New Mexico State University.

  13. Modeling The Water Table In The Middle Rio Grande River Riparian Corridor

    NASA Astrophysics Data System (ADS)

    Akasheh, O. Z.; Neale, C. M.

    2007-12-01

    The Middle Rio Grande River (MRGR) is the main source of fresh water for the state of New Mexico. An arid area with low water resources created a situation where water is extensively diverted or stored to supply the high demand for municipalities and agricultural activities. The extensive water diversions over the last few decades has affected the composition of the native riparian vegetation such as cottonwood and coyote willow and enhanced the spread of invasive species harmful to the river system such as Tamarisk and Russian Olives. The river aquatic system has also been badly affected. The need to study the river hydrological processes and their relation with its health is important to preserve the river ecosystem. The water table within the riparian zone is intrinsically connected to the flows in the river. Large withdrawals of water by Tamarisk affect the surface flows, which coupled with the large diversions for irrigation result in a complicated river management problem. In this paper we describe the methodology used to spatially model the water table depth between the river and the adjacent drains parallel to the river. Water table readings are used to check the model. Evapotranspiration by the riparian vegetation is estimated and included in the soil moisture balance. The model runs as an application in ArcGIS. Spatial layers include soils and riparian vegetation maps obtained from the classification of airborne high resolution multispectral imagery.

  14. Dust-on-snow and the Timing of Peak Streamflow in the Upper Rio Grande

    NASA Astrophysics Data System (ADS)

    Steele, C. M.; Elias, E.; Moffitt, A.; Beltran, I.; Rango, A.

    2015-12-01

    Dust radiative forcing on high elevation snowpack is well-documented in the southern Rockies. Various field studies show that dust deposits decrease snow albedo and increase absorption of solar radiation, leading to earlier snowmelt and peak stream flows. These findings have implications for the use of temperature-index snow runoff models (such as the Snowmelt Runoff Model [SRM]) for predicting streamflow. In previous work, we have used SRM to simulate historical streamflow from 26 Upper Rio Grande sub-basins. Because dust radiative forcing can alter the relation between temperature and snowmelt, we wanted to find out if there is evidence of dust radiative forcing and earlier snowmelt in our study basins, particularly for those years where SRM was less successful in simulating streamflow. To accomplish this we have used openly-available data such as EPA air quality station measurements of particulate matter up to 10 micrometers (PM10); streamflow data from the USGS National Water Information System and Colorado Division of Water Resources; temperature, precipitation and snow water equivalent (SWE) from NRCS SNOTEL stations and remotely sensed data products from the MODIS sensor. Initial analyses indicate that a connection between seasonal dust concentration and streamflow timing (date of onset of warm-season snowmelt, date of streamflow center-of-volume) can be detected. This is further supported by time series analysis of MODIS-derived estimates of snow albedo and dust radiative-forcing in alpine and open subalpine snow fields.

  15. [Work-related accidents: urban violence and death in Porto Alegre, Rio Grande do Sul, Brazil

    PubMed

    Oliveira; Mendes

    1997-01-01

    This article focuses on the magnitude of work-related deaths in Porto Alegre, the capital of Rio Grande do Sul State, Brazil. Death certificates were used to investigate 159 cases, or 18% of the 877 deaths from external causes in 1992. Some 31 cases were identified. The principal cause of death among these workers was homicide, with 58% of cases (15 from fire arms and 3 from knives), followed by traffic accidents, with 29% (5 motor vehicle collisions and 4 pedestrians run down by motor vehicles). Of these 31 deaths, 17 were workers from the formal labor market, of whom 11 did not fit into the regular reporting procedures for work-related accidents. The other 14 deaths were of workers from the informal labor market (7), individuals involved in illicit activities (6), and unknown (1), in which cases reporting as work-related accidents was also inappropriate. These data suggest negligence by the public sector in dealing with this issue and the fact that official statistics fail to reflect the reality of daily working conditions. The authors conclude that health surveillance requires other data collection mechanisms besides those used by the Social Welfare System, so as to include all actual risks related to work situations. PMID:10886939

  16. Heat and extension at mid- and lower crustal levels of the Rio Grande rift

    NASA Technical Reports Server (NTRS)

    Olsen, K. H.; Baldridge, W. S.; Callender, J. F.

    1985-01-01

    The process by which large amounts (50 to 200 percent) of crustal extension are produced was concisely described by W. Hamilton in 1982 and 1983. More recently, England, Sawyer, P. Morgan and others have moved toward quantifying models of lithospheric thinning by incorporating laboratory and theoretical data on rock rheology as a function of composition, temperature, and strain rate. Hamilton's description identifies three main crustal layers, each with a distinctive mechanical behavior; brittle fracturing and rotation in the upper crust, discontinuous ductile flow in the middle crust and laminar ductile flow in the lower crust. The temperature and composition dependent brittle-ductile transition essentially defines the diffuse boundary between upper and middle crust. It was concluded that the heat responsible for the highly ductile nature of the lower crust and the lensoidal and magma body structures at mid-crustal depths in the rift was infused into the crust by relatively modest ( 10 percent by mass) magmatic upwelling (feeder dikes) from Moho levels. Seismic velocity-versus-depth data, supported by gravity modeling and the fact that volumes of rift related volcanics are relatively modest ( 6000 cubic km) for the Rio Grande system, all imply velocities and densities too small to be consistent with a massive, composite, mafic intrusion in the lower crust.

  17. Serologic response of Rio Grande wild turkeys to experimental infections of Mycoplasma gallisepticum

    USGS Publications Warehouse

    Rocke, Tonie E.; Yuill, Thomas M.

    1988-01-01

    The serologic response of Rio Grande wild turkeys (Meleagris gallopavo intermedia) to Mycoplasma gallisepticum (MG) was determined. Free-ranging turkeys were caught in southern Texas, shipped to the University of Wisconsin, Madison, and housed in isolation facilities. Fourteen birds were exposed to MG, by intratracheal and intranasal inoculation. Eight birds received sterile broth only. Two wk prior to the end of the experiment, MG exposed turkeys were stressed by challenge with a serologically unrelated mycoplasma. Serum from all exposed birds reacted positively for MG antibody by the rapid plate agglutination (RPA) procedure within 2 mo postexposure (PE) and all but one remained positive for 14 mo PE. Less than one half of the exposed birds developed positive MG antibody titers detectable by the hemagglutination inhibition (HI) test within 2 mo PE, and by 10 mo PE, none had positive titers. Antibody was detected by the HI test in two of 11 infected turkeys, 14 mo PE, and titers increased significantly within 2 wk. MG was isolated from tracheal swabs from two infected birds 2 mo PE, but attempts thereafter failed. However, at the termination of the experiment 15 mo later, MG was isolated from lung tissue of three of 11 exposed turkeys and from a blood clot found in the lower trachea of one bird.

  18. Exposure to insecticides of brushland wildlife within the Lower Rio Grande Valley, Texas, USA

    USGS Publications Warehouse

    Custer, T.W.; Mitchell, C.A.

    1987-01-01

    Brushland wildlife within the Lower Rio Grande Valley of south Texas were studied following applications of eleven insecticides to nearby sugarcane or cotton fields. During the study no wildlife were found dead. Mean brain acetylcholinesterase (AChE) activity of great-tailed grackles (Quiscalus mexicanus) and mourning doves (Zenaida macroura) was significantly lower than controls following application of some organophosphorous insecticides. Brain AChE activity varied significantly among chemicals, days after exposure and application rates. Mean brain AChE activity of white-winged doves (Zenaida asiatica) and three small mammal species was not significantly different than their respective controls following application of insecticides. Mean brain AChE activity of grackles was inhibited significantly more than white-winged doves after application of Bolstar, EPN-methyl parathion, and Azodrin and significantly more than that of mourning doves after applications of Bolstar and EPN-methyl parathion. Our data indicate that there were no adverse effects on most brushland wildlife. Exposure was probably dependent upon use of the agricultural fields as feeding or resting sites and only grackles and mourning doves were regularly present in the fields.

  19. Exposure to insecticides of brushland wildlife within the lower Rio Grande valley Texas USA

    USGS Publications Warehouse

    Custer, T.W.; Mitchell, C.A.

    1987-01-01

    Brushland wildlife within the Lower Rio Grande Valley of south Texas were studied following applications of eleven insecticides to nearby sugarcane or cotton fields. During the study no wildlife were found dead. Mean brain acetycholinesterase (AChE) activity of great-tailed grackles (Quiscalus mexicanus) and mourning doves (Zenaida microura) was significantly lower than controls following application of some organophosphorus insecticides. Brain AChE activity varied significantly among chemicals, days after exposure and lactin rates. Mean brain AChE activity of white-winged doves (Zenaida asiatica) and three small mammals species was not significantly different than their respective control following application of the insecticides. Mean brain AChE activity of grackles was inhibited significantly more than white-winged doves after application of Bolstar, EPN-methyl parathion, and Azodrin and significantly more than that of mourning doves after applications of Bolstar and EPN-methyl parathion. Our data indicate that there were no adverse effects on most brushland wildlife. Exposure was probably dependent upon use of the agricultural fields as feeding or resting site and only grackles and mourning doves were regularly present in the fields.

  20. Determination of β haplotypes in patients with sickle-cell anemia in the state of Rio Grande do Norte, Brazil.

    PubMed

    Cabral, Cynthia Hatsue Kitayama; Serafim, Edvis Santos Soares; de Medeiros, Waleska Rayane Dantas Bezerra; de Medeiros Fernandes, Thales Allyrio Araújo; Kimura, Elza Miyuki; Costa, Fernando Ferreira; de Fátima Sonati, Maria; Rebecchi, Ivanise Marina Moretti; de Medeiros, Tereza Maria Dantas

    2011-07-01

    β(S) haplotypes were studied in 47 non-related patients with sickle-cell anemia from the state of Rio Grande do Norte, Brazil. Molecular analysis was conducted by PCR/RFLP using restriction endonucleases XmnI, HindIII, HincII and HinfI to analyze six polymorphic sites from the beta cluster. Twenty-seven patients (57.5%) were identified with genotype CAR/CAR, 9 (19.1%) CAR/BEN, 6 (12.8%) CAR/CAM, 1 (2.1%) BEN/BEN, 2 (4.3%) CAR/Atp, 1 (2.1%) BEN/Atp and 1 (2.1%) with genotype Atp/Atp. The greater frequency of Cameroon haplotypes compared to other Brazilian states suggests the existence of a peculiarity of African origin in the state of Rio Grande do Norte. PMID:21931513

  1. [Screening for hemoglobinopathies in blood donors from Caxias do Sul, Rio Grande do Sul, Brazil: prevalence in an Italian colony].

    PubMed

    Lisot, Cristina Lucia Alberti; Silla, Lúcia Mariano da Rocha

    2004-01-01

    The high prevalence of beta thalassemia among Italians and their participation in the ethnic formation of Caxias do Sul, Rio Grande do Sul State, Brazil, and neighboring cities prompted us to investigate hemoglobinopathies in 608 blood donors at the Caxias do Sul Regional Blood Center. Despite the ethnic influence, abnormal hemoglobin levels were found in only 1.81% of the donors (0.16% Hb AC, 0.99% Hb AS, and 0.66% Hb AH), similar to the levels observed in a study on qualitative disorders conducted in the rural area of Rio Grande do Sul. In our setting, the most commonly used screening tests for thalassemia, combined with DNA sequencing, were unable to detect quantitative hemoglobin synthesis disorders. This may be attributable to still-unknown genetic disorders, technical limitations, or simply to miscegenation. PMID:15608861

  2. [Homeopathic strategies: the Homeopathic League of Rio Grande do Sul in the 1940s and 1950s].

    PubMed

    Weber, Beatriz Teixeira

    2011-06-01

    Although the period following 1930 has been considered an era in which homeopathy lost ground within academia, homeopaths nevertheless were advocating for their proposals in a variety of spaces. One such instance was represented by the Homeopathic League of Rio Grande do Sul, founded in 1941, which published a journal until the 1970s, set up three free dispensaries to serve the population in Porto Alegre, and played an active role in political discussions through a group of homeopaths who endeavored to disseminate and expand homeopathic practice. An analysis of the League's Boletim de Homeopatia provides insight into homeopaths' strategies for expanding their role in Porto Alegre, capital of Rio Grande do Sul. PMID:21779687

  3. Irrigated rice area estimation using remote sensing techniques: Project's proposal and preliminary results. [Rio Grande do Sul, Brazil

    NASA Technical Reports Server (NTRS)

    Parada, N. D. J. (Principal Investigator); Deassuncao, G. V.; Moreira, M. A.; Novaes, R. A.

    1984-01-01

    The development of a methodology for annual estimates of irrigated rice crop in the State of Rio Grande do Sul, Brazil, using remote sensing techniques is proposed. The project involves interpretation, digital analysis, and sampling techniques of LANDSAT imagery. Results are discussed from a preliminary phase for identifying and evaluating irrigated rice crop areas in four counties of the State, for the crop year 1982/1983. This first phase involved just visual interpretation techniques of MSS/LANDSAT images.

  4. An application of cluster analysis for determining homogeneous subregions: The agroclimatological point of view. [Rio Grande do Sul, Brazil

    NASA Technical Reports Server (NTRS)

    Parada, N. D. J. (Principal Investigator); Cappelletti, C. A.

    1982-01-01

    A stratification oriented to crop area and yield estimation problems was performed using an algorithm of clustering. The variables used were a set of agroclimatological characteristics measured in each one of the 232 municipalities of the State of Rio Grande do Sul, Brazil. A nonhierarchical cluster analysis was used and the pseudo F-statistics criterion was implemented for determining the "cut point" in the number of strata.

  5. Llano Grande Center's Oral History Project Sparks Cultural and Economic Renewal in Texas's Rio Grande Valley. Rural Trust Featured Project.

    ERIC Educational Resources Information Center

    Null, Elizabeth Higgins

    The Llano Grande Center for Research and Development started as an oral history experiment in two of Texas's poorest school districts. Since the 1920s, when this arid region in the southernmost tip of Texas was first transformed into the orchards and farmlands of the "Magic Valley," workers of Mexican descent have worked the land. Over time,…

  6. Electromagnetic surveys to detect clay-rich sediment in the Rio Grande inner valley, Albuquerque area, New Mexico

    USGS Publications Warehouse

    Bartolino, James R.; Sterling, Joseph M.

    2000-01-01

    Information on the presence of clay-rich layers in the inner-valley alluvium is essential for quantifying the amount of water transmitted between the Rio Grande and the Santa Fe Group aquifer system. This report describes a study that used electromagnetic surveys to provide this information. In the first phase of the study, electromagnetic soundings were made using time-domain and frequency-domain electro- magnetic methods. On the basis of these initial results, the time- domain method was judged ineffective because of cultural noise in the study area, so subsequent surveys were made using the frequency-domain method. For the second phase of the study, 31 frequency-domain electromagnetic surveys were conducted along the inner valley and parallel to the Rio Grande in the Albuquerque area in the spring and summer of 1997 to determine the presence of hydrologically significant clay-rich layers buried in the inner-valley alluvium. For this report, the 31 survey sections were combined into 10 composite sections for ease of interpretation. Terrain-conductivity data from the surveys were modeled using interpretation software to produce geoelectric cross sections along the survey lines. This modeling used lithologic logs from two wells installed near the survey lines: the Bosque South and Rio Bravo 5 wells. Because of cultural interference, location of the wells and soundings, complex stratigraphy, and difficulty interpreting lithology, such interpretation was inconclusive. Instead, a decision process based on modeling results was developed using vertical and horizontal dipole 40-meter intercoil spacing terrain-conductivity values. Values larger than or equal to 20 millisiemens per meter were interpreted to contain a hydrologically significant thickness of clay-rich sediment. Thus, clay-rich sediment was interpreted to underlie seven segments of the 10 composited survey lines, totaling at least 2,660 meters of the Rio Grande inner valley. The longest of these clay

  7. On Ensino de Astronomia nas Cidades de Ribeirão Pires e Rio Grande da Serra

    NASA Astrophysics Data System (ADS)

    Faria, R. Z.; Voelzke, M. R.

    2007-08-01

    Apesar da astronomia ser um dos temas indicados pelos Parâmetros Curriculares Nacionais, observa-se que poucas mudanças ocorreram desde a implementação do mesmo em sala de aula. A presente pesquisa diz respeito sobre como os tópicos de astronomia estão sendo abordados pelos professores no ensino médio. Optou-se por aplicar um questionário com os professores que ministram a disciplina de física. Os mesmos trabalham em escolas estaduais situadas nas cidades de Ribeirão Pires e Rio Grande da Serra, ambas subordinadas a Diretoria de Ensino de Mauá, no Estado de São Paulo. O questionário foi aplicado durante o 2° semestre de 2006. Até o momento os resultados são preliminares. Dos 82,0% dos professores que responderam ao questionário no município de Rio Grande da Serra, 66,7% não aplicaram nenhum tópico de astronomia, 77,8% não utilizaram qualquer tipo de programa computacional, 66,7% não utilizaram laboratório, que 77,8% nunca levaram os alunos a museus e ou planetários e que 66,7% não indicaram qualquer tipo de revista ou livro sobre astronomia aos seus alunos. No município de Ribeirão Pires, 53,3% dos professores responderam ao questionário, destes 75,0% não aplicaram nenhum tópico de astronomia, 93,8% não utilizaram qualquer tipo de programa computacional, 75,0% não utilizaram laboratório, 81,3% nunca levaram os alunos a museus e ou planetário e 56,3% não indicaram qualquer tipo de revista ou livro sobre astronomia ao seus alunos. Apesar da maioria dos professores reconhecerem que o conteúdo de astronomia influi na formação do jovem, os mesmos não incluem o tema em seus planejamentos escolares.

  8. Configuration and Correlation of Fluvial Terrace Deposits In the Lower Rio Salado Valley: A Record of Magmatic Uplift and Active Normal Faulting in the Rio Grande Rift

    NASA Astrophysics Data System (ADS)

    Sion, B. D.; Axen, G. J.; Phillips, F. M.; Harrison, B.

    2015-12-01

    The Rio Salado is a western tributary of the Rio Grande whose valley is flanked by six major terrace levels. The Rio crosses several active rift-related normal faults and the active, mid-crustal Socorro Magma Body (SMB; a sill at 19 km depth that is actively doming the land surface), providing an unusual opportunity to explore the effects of deep magma emplacement and active faulting on the terraces. Rio Salado terraces were mapped using a high-resolution DEM and digital color stereophotographs and were projected onto a valley-parallel vertical plane to construct longitudinal profiles. Three new soil pits were described to aid terrace correlation. A net incision rate of 0.41 ± 0.06 m/ka was inferred from the correlation of a major fill-cut terrace to the 122 ± 18 ka Airport surface ~25 km south of the Rio Salado. This incision rate is >1.5 times more rapid than estimated rates nearby or in other parts of New Mexico, but yields age estimates for other terraces that are consistent with soil development. Terrace gradients in the Rio Salado have increased through time, indicating either stream response to Rio Grande incision or footwall tilting from the Quaternary Loma Blanca fault (LBF). Two terraces in the LBF hanging wall are back-tilted relative to their footwall counterparts, suggesting a listric geometry for the LBF. However, two others (Qtf and Qtc) are east-tilted relative to their footwall counterparts. Both Qtf and Qtc merge eastward with the next youngest terrace in the flight, and Qtc is arched, consistent with an earlier episode of surface uplift above the SMB. Future work will involve (a) additional terrace mapping over the SMB, (b) cosmogenic 36Cl depth profile dating of the Rio Salado terraces to determine incision rates, allow regional terrace correlations, and constrain fault-slip slip rates and the record of SMB-related surface uplift, and (c) numerical modeling of SMB inflation constrained by uplift signals.

  9. Hydrogeological characterization of a bank filtration experiment site at the Rio Grande, El Paso, Texas, USA

    NASA Astrophysics Data System (ADS)

    Langford, R.; Schulze-Makuch, D.; Pillai, S.; Abdel-Fattah, A.; Widmer, K.

    2003-04-01

    An experiment site was constructed along an artificial channel of the Rio Grande in El Paso, Texas. The experiment was funded by the EPA and is designed to measure the effectiveness of bank filtration in an arid environment. Regionally, the experiment is important because of the hundreds of thousands of people drinking water from shallow wells drilled in close proximity to septic systems. A pumping well was drilled 17 meters from the stream bank and screened from 3.5 to 8 m depth. A cruciform array of observation wells with several multilevel completions allows detection of downstream and vertical movement of water as well as flow from the stream to the well. All of the wells were continuously cored during drilling. Analysis of the cores reveals that the site consists of two stacked channels filled with sand deposited from the meandering Rio Grande. A grid of ground-penetrating radar lines provided three-dimensional coverage between wells and showed bedding to 6.5 m depth. Constant head hydraulic conductivities show that the aquifer consists of two more permeable units separated by the less permeable upper fill of the lower channel complex, with vertical hydraulic conductivities of (1x10-6 to 2x10-6 m/s?). The intervals above and below this interval have the highest vertical conductivities (up to 3.5x10-5 m/s). A multiple pumping and tracer test was conducted using the cruciform array of the field site that consisted of a pumping well, 16 observation wells, and a stream sampling point. The average hydraulic conductivity of the geological media at the field site was about 2 x 10-3 m/s based on pumping test analysis. However, the type curve responses revealed significant heterogeneity of hydraulic conductivity throughout the field site. For the tracer test, bromide and microspheres were used as tracers. Microspheres were used to mimic the behavior of Giardia and Cryptosporidium. The tracers (bromide and microspheres of different sizes and colors) were injected in one

  10. Creating a standardized watersheds database for the Lower Rio Grande/Río Bravo, Texas

    USGS Publications Warehouse

    Brown, J.R.; Ulery, Randy L.; Parcher, Jean W.

    2000-01-01

    This report describes the creation of a large-scale watershed database for the lower Rio Grande/Río Bravo Basin in Texas. The watershed database includes watersheds delineated to all 1:24,000-scale mapped stream confluences and other hydrologically significant points, selected watershed characteristics, and hydrologic derivative datasets.Computer technology allows generation of preliminary watershed boundaries in a fraction of the time needed for manual methods. This automated process reduces development time and results in quality improvements in watershed boundaries and characteristics. These data can then be compiled in a permanent database, eliminating the time-consuming step of data creation at the beginning of a project and providing a stable base dataset that can give users greater confidence when further subdividing watersheds.A standardized dataset of watershed characteristics is a valuable contribution to the understanding and management of natural resources. Vertical integration of the input datasets used to automatically generate watershed boundaries is crucial to the success of such an effort. The optimum situation would be to use the digital orthophoto quadrangles as the source of all the input datasets. While the hydrographic data from the digital line graphs can be revised to match the digital orthophoto quadrangles, hypsography data cannot be revised to match the digital orthophoto quadrangles. Revised hydrography from the digital orthophoto quadrangle should be used to create an updated digital elevation model that incorporates the stream channels as revised from the digital orthophoto quadrangle. Computer-generated, standardized watersheds that are vertically integrated with existing digital line graph hydrographic data will continue to be difficult to create until revisions can be made to existing source datasets. Until such time, manual editing will be necessary to make adjustments for man-made features and changes in the natural landscape

  11. A Regional Geothermal Assessment of the Rio Grande Rift: All Data Are Not Created Equal

    NASA Astrophysics Data System (ADS)

    Chapman, D. S.; D'Alfonso, D.; Hardwick, C.; Hollingshaus, B.; Kordy, M. A.; Shurtleff, R.; Smith, K.; Smith, S.

    2011-12-01

    In response to growing interest in geothermal energy, the University of Utah enrolled 22 geoscience and engineering students in a fall semester 2010 course "Geothermal Systems for Geoscientists." Seven of those students continued in a spring semester seminar, sponsored by NREL (National Renewable Energy Laboratory), to create a case study on the geothermal potential of the Rio Grande Rift. The assessment, grounded in informatics, began with a complete inventory of all printed and web resources for the region. ArcMAP was used to create a suitable base map and, through extensive data mining, to spatially correlate relevant demographic, infrastructure, and geothermal datasets. Of the more than 40 spatial data overlays available, we determined the following data to be most useful in making a geothermal assessment: (1) heat flow measurements, (2) geochemistry of spring and well waters, (3) geologic mapping focused on young volcanics and intrusives, and (4) regional and local hydrology. Infrastructure (power plant, power line, population centers, and highway locations) became important only after the geothermal resource was identified. We identified four potential geothermal reservoir sites, two of which were chosen for detailed reservoir quantification and geothermal development plans. Thermal energy in each reservoir was calculated and compared to results computed with the software package GEOFRAT. The Mt. Princeton site is considered as an example of a high temperature reservoir suitable for binary plant power generation. The power potential for a 30-year use is estimated to be 8.5 MWelectric. The second system is more appropriate for direct heat application. Land-use regulations limit access for geothermal development of the Valles Caldera system to an extensive low temperature reservoir in Jemez Springs estimated at 1.1 GWthermal. In developing geothermal case studies, this student driven project has demonstrated the importance of both (a) using geothermal science

  12. Characterization of stormwater discharges from Las Flores Industrial Park, Rio Grande, Puerto Rico, 1998-99

    USGS Publications Warehouse

    Rodriguez, Jose M.

    2000-01-01

    Stormwater discharges from Las Flores Industrial Park, Rio Grande, Puerto Rico, were characterized from June 1998 to July 1999 by measuring the flow rate at two outfalls, delineating the drainage areas for each outfall, and calculating the volume of the stormwater discharges. Stormwater-discharge samples were collected and analyzed to determine the quality of the discharges. Constituent loads and loads per area were estimated for each drainage area. The studied drainage subareas covered approximately 46 percent of the total area of the Las Flores Industrial Park. Industrial groups represented in the study areas include manufacturers of textile, electronics, paper, fabricated metal, plastic, and chemical products. The concentrations of oil and grease (1 to 6 milligrams per liter), biochemical oxygen demand (4.7 to 16 milligrams per liter), total organic carbon (5.8 to 36 milligrams per liter), total suspended solids (28 to 100 milligrams per liter), and total phosphorous (0.11 to 0.78 milligrams per liter) from all the samples collected were less than the U.S. Environmental Protection Agency stormwater benchmark concentrations. Concentrations of chemical oxygen demand (15.8 to 157 milligrams per liter) and nitrate and nitrite (0.06 to 1.75 milligrams per liter) exceeded benchmark concentrations at one of the studied drainage areas. Total Kjeldahl nitrogen concentrations (1.00 to 3.20 milligrams per liter) exceeded the benchmark concentrations at the two studied drainage areas. Maximum concentrations for oil and grease, biochemical oxygen demand, chemical oxygen demand, total organic carbon, total Kjeldahl nitrogen, nitrate plus nitrite, and total phosphorous were detected in an area where electronics, plastics, and chemical products are currently manufactured. The maximum concentration of total suspended solids was detected at an area where textile, paper, plastic, chemical, and fabricated metal products are manufactured.

  13. Prevalence and Correlates of Physical Inactivity among Older Adults in Rio Grande do Sul, Brazil

    PubMed Central

    Souza, Adelle M. R.; Fillenbaum, Gerda G.; Blay, Sergio L.

    2015-01-01

    Background Current information on the epidemiology of physical inactivity among older adults is lacking, making it difficult to target the inactive and to plan for interventions to ameliorate adverse effects. Objectives To present statewide representative findings on the prevalence of physical inactivity among older community residents, its correlates and associated health service use. Methods A representative non-institutionalized random sample of 6963 individuals in Rio Grande do Sul, Brazil, aged ≥60 years, was interviewed face-to-face. Information was obtained on demographic characteristics, social resources, health conditions and behaviors, health service use, and physical inactivity. Controlled logistic regression was used to determine the association of physical inactivity with these characteristics. Results Overall, 62% reported no regular physical activity. Physical inactivity was significantly more prevalent among women, older persons, those with lower education and income, Afro-Brazilians (73%; White: 61%; “other”: 64%), those no longer married, and was associated with multiple individual health conditions and impaired activities of daily living (ADL). In adjusted analyses, associations remained for sociodemographic characteristics, social participation, impaired self-rated health, ADL, vision, and depression (odds ratios (OR) 1.2–1.7). Physically inactive respondents were less likely to report outpatient visits (OR 0.81), but more likely to be hospitalized (OR 1.41). Conclusions Physical inactivity is highly prevalent, particularly among Afro -Brazilians. It is associated with adverse sociodemographic characteristics; lack of social interaction; and poor self-rated health, ADL, vision, and depression; although not with other health conditions. Self-care may be neglected, resulting in hospitalization. PMID:25700161

  14. Gravity and Seismic Investigations of the Northern Rio Grande Rift, New Mexico

    NASA Astrophysics Data System (ADS)

    Biehler, S.; Braile, L. W.; Harper, C.; Bartz, R.; Donnelly, W.; Haga, L.; Keithline, N.; McBride, K.; Miller, D.; Oberle, J.; Wahl, J.; Castrejon-Martinez, R.; Lee, R. F.; Saez Berrios, P.; Ferguson, J. F.; Baldridge, W. S.

    2015-12-01

    Participants in the Summer of Applied Geophysical Experience (SAGE) program have collected gravity data at over 7000 locations in the northern Rio Grande rift (RGR) area of New Mexico in the past thirty-three years. In recent years, the SAGE program has focused on the western edge of the Española basin and the transition into the Santo Domingo basin of the RGR. During this time, we have collected about 40 km of seismic reflection and refraction data along approximately East-West profiles using a 120 channel data acquisition system with a 20 m station interval and a Vibroseis source. Refraction travel time modeling and Common Midpoint (CMP) stacked reflection sections have imaged basin boundary faults and stratigraphy. We also have access to several energy-industry seismic reflection record sections from the 1970s in the study area. These data and some deep drill hole information have allowed detailed interpretation of basin structures along segments of three regional transects across the RGR in northern New Mexico. The interpreted seismic velocities and fault images from the seismic record sections, and lithologies and well logs from drill holes, have also provided important constraints on modeling and interpretation of the regional gravity data along the three transects. The gravity modeling along these transects reveals key structures within the basin including the eastern bounding fault of the Los Alamos graben, eastern boundary faults of the Santo Domingo basin, the Agua Fria fault system near the eastern boundary of the Española basin and interpreted depths to basement of the Española and Santo Domingo basins. Boundary fault offsets are as large as 3 km and maximum basin depths range from 3 to 6 km.

  15. Hematozoan parasites of Rio Grande wild turkeys from southern Texas (USA)

    USGS Publications Warehouse

    Castle, Marc D.; Christensen, Beth A.; Rocke, Tonie E.

    1988-01-01

    One hundred twenty-three of 300 blood samples (41%) taken from Rio Grande wild turkeys (Meleagris gallopavo intermedia) from three locations in southern Texas (Welder Wildlife Refuge, Chaparrosa Ranch, and Campo Alegre Ranch) and subinoculated into domestic broad-breasted white turkey poults were positive for a Plasmodium (Novyella) sp. Analysis of blood films from 350 turkeys revealed Haemoproteus meleagridis in 76% of the birds. A significantly greater mean parasite intensity was observed in birds from Welder Wildlife Refuge. Birds from the Campo Alegre Ranch exhibited a significantly higher prevalence of H. meleagridis than birds from Chaparrosa. The Plasmodium sp. was infective for canaries (Serinus canaria), bobwhites (Colinus virginianus), and ring-necked pheasants (Phasianus colchicus), but would not produce infection in white leghorn chickens (Gallus gallus) or Coturnix quail (Coturnix coturnix). Attempts to infect Culex tarsalis and C. pipiens pipiens were unsuccessful. Asexual erythrocytic synchrony was not observed when blood-induced infections were monitored in two domestic turkey poults every 4 hr for 72 hr. Exoerythrocytic stages were not found upon examination of impression smears and tissue samples taken from brain, liver, spleen, kidney, lung, and bone marrow. The Plasmodium sp. is most similar morphologically to three species in the subgenus Novyella, P. hexamerium, P. vaughani, and P. kempi. The most striking similarities are to P. hexamerium, and involve mean merozoite number, erythrocytic schizont location, and vertebrate host susceptibility. It differs from P. vaughani in being able to infect turkeys and in type of parasitized erythrocytes. Differences to P. kempi include mean merozoite number, and ability to infect pheasants, and its inability to develop inC. pipiens and C. tarsalis.

  16. Salmonelloses in the State of Rio Grande do Sul, southern Brazil, 2002 to 2004

    PubMed Central

    Wagner, Vanessa Rech; Silveira, Josete Baialardi; Tondo, Eduardo Cesar

    2013-01-01

    Salmonella has been identified as the main aetiological agent responsible for foodborne diseases in several countries worldwide, including Brazil. In the State of Rio Grande do Sul (RS), southern Brazil, previews studies analysed official foodborne illnesses data, identifying Salmonella as the main bacterial agent of foodborne diseases during the period of 1997 to 2001. The present study aimed to analyse the official epidemiological data on salmonelloses occurred in the State of RS, during the period of 2002 to 2004. Even though data on recent salmonelloses were available, only data concerning the period comprising in 2002 to 2004 were analysed because the official worksheet records presented more consistent information about the salmonellosis outbreaks. Results indicated that, among the 624 foodborne outbreaks officially investigated, 202 (32.37%) were confirmed as salmonellosis. Among them 23,725 people were involved, 4,148 became sick, 1,878 were hospitalized and one person died. The season with the highest incidence of salmonelloses was spring, and the most affected age group was composed of people aged between 20 to 49 years old (56.66%). Animal origin foods - especially eggs and meat products - were very often involved with the outbreaks, however homemade mayonnaise was identified as the main food vehicle for salmonelloses (53.51%). The majority of the cases occurred inside private homes (55.81%) and food services (12.1%), and the main factors contributing to the occurrence of the outbreaks were the consumption of products without sanitary inspection (26.7%) and exposure of food at room temperature for more than two hours (18.58%). Similarly to what was previously reported for the period of 1997 to 2001, Salmonella spp. was the most prevalent foodborne disease agent in the State of RS during the years of 2002 to 2004. PMID:24516439

  17. Basalt volatile fluctuations during continental rifting: An example from the Rio Grande Rift, USA

    NASA Astrophysics Data System (ADS)

    Rowe, Michael C.; Lassiter, John C.; Goff, Kathleen

    2015-05-01

    Hydration and metasomatism of the lithospheric mantle potentially influences both the magmatic and tectonic evolution of southwestern North America. Prior studies have suggested that volatile enrichments to the mantle underlying western North America resulted from shallow subduction of the Farallon Plate during the Laramide (˜74-40 Ma). This study examines temporal and spatial variations in volatile elements (H2O, Cl, F, and S) determined from olivine and orthopyroxene-hosted melt inclusions along and across the Rio Grande Rift, the easternmost extent of Laramide shallow subduction. Maximum chlorine enrichments are observed in the southern rift with a Cl/Nb of ˜210 and reduce with time to MORB-OIB levels (˜5-17). Measured water abundances are <0.8 wt % in rehomogenized inclusions; however, calculated H2O, based on Cl/Nb systematics, primarily varies from 0.5 to 2 wt % H2O. Sulfur abundances (<0.61 wt %), and calculated sulfide saturation, indicate magmas with high Cl/Nb also contain oxidized sulfur. The abundance of fluorine in melt inclusions (up to 0.2 wt %) is not correlated to other volatile elements. Temporal variations in melt inclusion volatile abundances coupled with varying isotopic (Sr-Nd-Pb) whole-rock systematics suggest a transition from lithospheric to asthenospheric melt generation in the southern RGR and potential lithosphere-asthenosphere melt mixing in the central RGR. East to west decrease in volatile enrichment likely reflects a combination of varying mantle sources and early removal of metasomatized lithospheric mantle underlying regional extension. Results indicate, from multiple causes, subduction-related volatile enrichment to the lithospheric mantle is ephemeral, and strong enrichments in volatiles are not preserved in active magmatic-tectonic provenances.

  18. Gravity and Seismic Investigations of the Santo Domingo Basin, Rio Grande Rift, New Mexico

    NASA Astrophysics Data System (ADS)

    Braile, L. W.; Ferguson, J. F.; Boucher, C.; Novitsky, C. G.; O'Shea, P. M.; Daves, J.; Marzen, R.; Mendoza, K.; Rasmussen, T.; Wei, W.; Baldridge, W. S.; Biehler, S.; Claytor, J. M.; Bischoff, S. H.; Ranasinghe, N. R.; Corredor, A.

    2014-12-01

    The SAGE (Summer of Applied Geophysical Experience) program collected new gravity, seismic, electromagnetic and down-hole temperature data in 2014 in the Santo Domingo Basin and adjacent areas of the Rio Grande Rift (RGR) area of northern New Mexico. The SAGE 2014 data collection was part of an integrated geophysical study of the area initiated in 2010 and adds data and interpretations to a W to E transect of the RGR. The transect includes previous SAGE seismic refraction and CMP reflection profiles recorded in 2010 and 2011, some industry seismic reflection data, and detailed gravity observations. Seismic data consisted of a 4.8 km NW to SE profile (120 three-component stations in four overlapping deployments, 20 m station spacing, using a Vibroseis source - 20 m spacing for reflection VPs; 800 m spacing for refraction VPs) along the Borrego Canyon road with both refraction and CMP reflection coverage. About 50,000 seismograms were recorded. The surface conditions (dry unconsolidated sediments) increased surface wave energy and limited the signal-to-noise level of reflection arrivals although some wide-angle reflections with two-way times as great as 1.8 s were visible. The refraction data were modeled with first arrival travel time methods and mainly helped identify the velocity and minimum thickness of the Tertiary Santa Fe group sedimentary rocks in the Santo Domingo Basin. Interpretation of the seismic and gravity data along the transect was aided by refraction velocities, the existence of a nearby regional seismic reflection profile from industry, and lithologies and well-logs from a deep well. Gravity modeling, with significant control on depths of interfaces and densities from the seismic and drill hole data, indicates that the Santo Domingo sedimentary basin has a total depth of about 6 km.

  19. River management impacts on riparian forest vegetation along the Middle Rio Grande: 1935-2014

    NASA Astrophysics Data System (ADS)

    Petrakis, Roy E.

    Riparian ecosystems of the southwestern United States are highly valuable to both the ecological and human communities which surround them. Over the past century, they have been subject to shifting management practices to maximize human use, control, ecosystem service, and conservation. This creates a complex relationship between water policy, management, and the natural ecosystem necessitating research on spatial and temporal dynamics of riparian vegetation. The San Acacia Reach of the Middle Rio Grande, a 60 mile stretch from the San Acacia Diversion Dam to San Marcial, has experienced multiple management and river flow fluctuations over the past 80 years, resulting in threats to riparian and aquatic ecosystems. This research was completed through the use and analysis of multi-source remote sensing data, GIS, and a review of the on-the-ground management decisions to better understand how the location and composition of the riparian vegetation has been affected by these shifting practices. This research focused on four phases, each highlighting different management practices and river flow patterns during the last 80-years. Each of these periods provides a unique opportunity to observe a direct relationship between river management and riparian land cover response and change. Overall, management practices reduced surface river flows and limited overbank flooding and resulted in changes in the composition, density, and spatial patterns of the vegetation, including increased non-native vegetation growth. Restoration efforts over the past few decades have begun to reduce the presence of non-native species. Despite these changes, this ecosystem was shown to be extremely resilient in maintaining its function/service throughout the entire study time frame.

  20. The role of feedback mechanisms in historic channel changes of the lower Rio Grande in the Big Bend region

    NASA Astrophysics Data System (ADS)

    Dean, David J.; Schmidt, John C.

    2011-03-01

    Over the last century, large-scale water development of the upper Rio Grande in the U.S. and Mexico, and of the Rio Conchos in Mexico, has resulted in progressive channel narrowing of the lower Rio Grande in the Big Bend region. We used methods operating at multiple spatial and temporal scales to analyze the rate, magnitude, and processes responsible for channel narrowing. These methods included: hydrologic analysis of historic stream gage data, analysis of notes of measured discharges, historic oblique and aerial photograph analysis, and stratigraphic and dendrogeomorphic analysis of inset floodplain deposits. Our analyses indicate that frequent large floods between 1900 and the mid-1940s acted as a negative feedback mechanism and maintained a wide, sandy, multi-threaded river. Declines in mean and peak flow in the mid-1940s resulted in progressive channel narrowing. Channel narrowing has been temporarily interrupted by occasional large floods that widened the channel, however, channel narrowing has always resumed. After large floods in 1990 and 1991, the active channel width of the lower Rio Grande has narrowed by 36-52%. Narrowing has occurred by the vertical accretion of fine-grained deposits on top of sand and gravel bars, inset within natural levees. Channel narrowing by vertical accretion occurred simultaneously with a rapid invasion of non-native riparian vegetation ( Tamarix spp., Arundo donax) which created a positive feedback and exacerbated the processes of channel narrowing and vertical accretion. In two floodplain trenches, we measured 2.75 and 3.5 m of vertical accretion between 1993 and 2008. In some localities, nearly 90% of bare, active channel bars were converted to vegetated floodplain during the same period. Upward shifts of stage-discharge relations occurred resulting in over-bank flooding at lower discharges, and continued vertical accretion despite a progressive reduction in stream flow. Thus, although the magnitude of the average annual

  1. Seasonal changes in 17-ß estradiol of the Rio Grande Chub (Gila pandora) in south-central New Mexico

    USGS Publications Warehouse

    Caldwell, Colleen A.; Fuller, S. Adam; Gould, William R.; Turner, Paul R.; Hallford, Dennis M.

    2004-01-01

    Timing of gametogensis and thus spawning can be inferred through changes in plasma concentrations of gonadal hormones. In preparation for ovulation and spawning, mean concentrations of 17ß-estradiol in a population of Rio Grande chub (Gila pandora) occupying the Rio Bonito, New Mexico, peaked at 37.6 ng/mL on 16 June and declined to 1.50 ng/mL by 11 August. Similarly, the gonadal somatic index (GSI) increased from 9.02 on 21 May (n = 9) to 11.85 on 16 June (n = 2) and declined to 6.10 on 11 August (n = 2). Peak concentrations of 17ß-estradiol and elevated GSI in June coincided with peak daylength for the year (14 h and 12 min) and average water temperature of 15.1°C. Concentrations of 17ß-estradiol remained low through 3 October indicating no additional spawning events in the Rio Grande chub population. We demonstrated 17ß-estradiol is a nondestructive and thus useful tool in estimating timing of spawning in a wild fish population.

  2. Tracing Anthropogenic Salinity Inputs to the Semi-arid Rio Grande River: A Multi-isotope Tracer (U, S, B and Sr) Approach

    NASA Astrophysics Data System (ADS)

    Garcia, S.; Nyachoti, S. K.; Ma, L.; Szynkiewicz, A.; McIntosh, J. C.

    2015-12-01

    High salinity in the Rio Grande has led to severe reductions in crop productivity and accumulation of salts in soils. These pressing issues exist for other arid rivers worldwide. Salinity contributions to the Rio Grande have not been adequately quantified, especially from agriculture, urban activities, and geological sources. Here, we use major element concentrations and U, S, B, Sr isotopic signatures to fingerprint the salinity sources. Our study area focuses on a 200 km long stretch of the Rio Grande from Elephant Butte Reservoir, NM to El Paso, TX. River samples were collected monthly from 2014 to 2015. Irrigation drains, groundwater wells, city drains and wastewater effluents were sampled as possible anthropogenic salinity end-members. Major element chemistry, U, S and Sr isotope ratios in the Rio Grande waters suggest multiple salinity inputs from geological, agricultural, and urban sources. Natural upwelling of groundwater is significant for the Rio Grande near Elephant Butte, as suggested by high TDS values and high (234U/238U), 87Sr/86Sr, δ34S ratios. Agricultural activities (e.g. flood irrigation, groundwater pumping, fertilizer use) are extensive in the Mesilla Valley. Rio Grande waters from this region have characteristic lower (234U/238U), 87Sr/86Sr, and δ34S ratios, with possible agricultural sources from use of fertilizers and gypsum. Agricultural practices during flood irrigation also intensify evaporation of Rio Grande surface water and considerably increase water salinity. Shallow groundwater signatures were also identified at several river locations, possibly due to the artificial pumping of local groundwater for irrigation. Impacts of urban activities to river chemistry (high NO3 and B concentrations) were evident for locations downstream to Las Cruces and El Paso wastewater treatment plants, supporting the use of the B isotope as an urban salinity tracer. This study improves our understanding of human impacts on water quality and elemental

  3. Evidence from mantle xenoliths for lithosphere removal beneath the central Rio Grande Rift

    NASA Astrophysics Data System (ADS)

    Byerly, Benjamin L.; Lassiter, John C.

    2012-11-01

    Seismic tomography beneath the Central Rio Grande Rift (RGR) at ˜34°N shows a low P and S wave velocity zone in the mantle that extends up the base of the Moho. This low-velocity region has been interpreted by (Gao et al., 2004) to be the result of convective removal of a portion of the once >100 km thick Proterozoic lithosphere. The amount of extension in the central RGR is thought to be low (˜25%) and thus cannot account for the amount of lithosphere thinning suggested by seismic tomography. We measured whole rock and mineral major element, trace element, and isotopic compositions of spinel-peridotite xenoliths erupted along the central axis of the rift (Elephant Butte) and the eastern margin of the Colorado Plateau (Cerro Chato) to determine their depth of origin and mantle provenance and to test the delamination hypothesis. If lithosphere removal has not occurred and the low P and S wave velocities are instead the result of hydration or melt infiltration in the lithosphere, then xenoliths erupted on the rift axis should have geochemical compositions similar to Proterozoic sub-continental lithospheric mantle (SCLM). At Cerro Chato, on the margin of the Colorado Plateau, xenoliths were derived from ˜60 km depth and have geochemical signatures similar to Proterozoic sub-continental lithospheric mantle (e.g. refractory major element compositions, LREE-enrichment, enriched Sr and Nd isotopes, unradiogenic Os isotopes). At Elephant Butte, along the central rift axis, two distinct groups of xenoliths are present. The majority of xenoliths from Elephant Butte are LREE-depleted and have fertile major element compositions. Additionally, these xenoliths have isotopic signatures similar to the range for DMM (e.g. 87Sr/86Sr ranging from 0.7018 to 0.7023, ɛNd ranging from 7 to 21, and 187Os/188Os ranging from 0.122 to 0.130). We interpret this group of xenoliths to be derived from asthenospheric mantle. A less-abundant group of xenoliths at Elephant Butte are LREE

  4. Paleoseismology and Fault Interactions of the Pajarito Fault System, Rio Grande Rift, New Mexico

    NASA Astrophysics Data System (ADS)

    Gardner, J. N.; Lewis, C. J.; Lavine, A.; Reneau, S. L.; Schultz, E. S.

    2006-12-01

    The Pajarito fault system is the local active boundary fault of the Rio Grande rift in the vicinity of Los Alamos, New Mexico. Detailed geologic and geomorphic mapping, and displacement-length profiles, reveal a complex pattern of structural deformation that suggests interaction and connective growth among the principal faults in the system (Pajarito, Rendija Canyon, Guaje Mountain, and Santa Clara faults, totaling ~55 km in length). At the surface, the Pajarito fault is not a single shear surface but a complex zone of deformation with considerable lateral variation in structural style from south to north. In the area of detailed mapping, the Pajarito fault is a broad zone of distributed deformation: at the southwest corner of the area, structure is dominated by a large monocline, but small faults and monoclines span a breadth of about 2 km with about 125 m of displacement in the last 1.2 million years; at the west central part of the area, the Pajarito fault is expressed as mainly a large normal fault with smaller faults spread across about 1 km with about 80 m of displacement in the last 1.2 million years; and, in the northwestern part of the area, structure is again dominated by a large monocline with normal faulting in a zone about 1.5 km wide with about 65 m of displacement in the last 1.2 million years. These along-strike variations in the deformation of the Pajarito fault suggest that in most places the tip of the master fault does not break the surface; instead, most of what can be observed is subsidiary structure. The implication of the complex structure and styles of deformation in the fault is that it severely complicates paleoseismic exploration for hazard analyses because different subsidiary structures rupture in different seismic events; no individual structure can be identified with even a near- complete paleoseismic record. Additionally, surface rupture hazards must be associated with broad zones instead of individual faults. Seven paleoseismic

  5. Characterization of the August 2009 New Mexico earthquake swarm in the central Rio Grande rift

    NASA Astrophysics Data System (ADS)

    Stankova-Pursley, J.; Bilek, S. L.; Ruhl, C. J.; Aster, R. C.; Rowe, C. A.; Johnson, J. B.

    2009-12-01

    Seismicity in central New Mexico, southwestern United States, is dominated by earthquakes occurring above the mid-crustal Socorro Magma Body (SMB). The SMB is a sill-like feature ≥ 3400 km2 in area, with a top surface at 19-km depth spanning the inner Rio Grande rift half-graben system. Inflation of the magma body at rates of several mm/year, perhaps coupled with shallow transport of aqueous fluids, is the prevailing model for the region’s long-standing and anomalous seismicity. Clustered swarms of small magnitude earthquakes have been noted since the 1860s throughout this region, and have been recorded instrumentally since the early 1960’s. Beginning in late August 2009, a very productive swarm of over 400 earthquakes (as of September 2, 2009) marks the most active period since 2005. Preliminary locations of over 50 of the largest events (local magnitude ML > 0.5) highlight a very small volume (~ 12 km3), suggesting that this swarm has occurred along an isolated portion of a rift-parallel fault. Depths are well-resolved through the use of top-side magma body reflections, and most of these events have occurred between 5 and 6 km depth, although a few occurred shallower. Felt and heard reports have been filed for several of the larger (ML > 1.9) events. We present seismic data from a local short period seismic network, available USArray Transportable Array seismic stations, and a temporary broadband instrument deployment as well as infrasound data from a temporary infrasound deployment to characterize this swarm. Focal mechanisms for the larger earthquakes are determined using all available seismic data and interpreted in the context of local geologic structure. We improve on preliminary network locations by applying waveform cross-correlation to improve arrival time picks. We also estimate a more complete catalog of the seismicity by using similar waveform scanning technique to identify additional events and place in the historical context of cumulative

  6. The Evolution of Riparian Landscape Elements Following Upstream Regulation and Depletion on the Rio Grande

    NASA Astrophysics Data System (ADS)

    Everitt, B. L.

    2006-12-01

    In 1915 closure of Elephant Butte Dam in central New Mexico profoundly altered the hydrologic regime of the Rio Grande for 560 km downstream, and set in motion a cascade of interwoven geomorphic, biological, and cultural responses. Geomorphic response included shrinking of the width and depth of the channel, and an increase in sinuosity. Cultural responses included artificial channel modification on 320 km of the river within the boundaries of the original irrigation project, beginning in 1933. The pre-dam river and its flood plain consisted of a mosaic of geomorphic elements that formed a functional riverine landscape, and founded a diverse habitat for the plants, animals, and people that lived there. A preliminary comparison of the modern river with pre-dam topographic mapping permits identification of individual landscape elements, including overflow land (flood plain) both cultivated and uncultivated, with oxbows and back-swamps. The pre-dam channel included a low water thread and un-vegetated flood bars. From pre-dam description and photographs we can assume the usual complement of pools and riffles, point bars and undercut banks. Until dredged in the 1970s, the unmodified reach retained the entire suite of landscape elements, although in somewhat different proportions from the pre-dam river, and remained a functional riparian system. Channel sinuosity increased from 1.45 in 1910 to 1.7 in 1970, thus riverbank habitat increased by 1.17%. In 1970 undercut banks still provided protection for fish, and point bars generated by lateral migration still provided seed beds for pioneer species. The smaller shallower channel raised groundwater beneath the flood plain and retarded flood waves, creating a generally more mesic environment, although the river occasionally dries up, as it did prior to 1915. In contrast, an impoverished suite of landscape elements characterizes the channelized reach. Lateral stability precludes point bars and undercut banks. Bounding levees

  7. Cooperation on Climate Services in the Binational Rio Grande/Bravo Basin

    NASA Astrophysics Data System (ADS)

    Garfin, G. M.; Shafer, M. A.; Brown, D. P.

    2013-12-01

    The Rio Grande/Bravo River Basin (RGB) of the United States and México is exposed to tornadoes, severe storms, hurricanes, winter storms, wildfire, and drought. The combination of these weather and climate-related hazards has resulted in impacts, such as wildfire, crop loss, water supply reduction, and flooding, with exceedingly high economic costs ($13 billion in 2011). In order to contribute to increased binational information flow and knowledge exchange in the region, we have developed a prototype quarterly bilingual RGB Climate Outlook, in PDF, supplemented by Twitter messages and Facebook posts. The goal of the project is to improve coordination between institutions in the U.S. and Mexico, increase awareness about climate variations, their impacts and costs to society, and build capacity for enhanced hazard preparedness. The RGB Outlook features a synthesis of climate products, impact data and analysis, is expressed in user-friendly language, and relies substantially on visual communication in contrast to text. The RGB Outlook is co-produced with colleagues in the U.S. and Mexico, in conjunction with the North American Climate Services Partnership (NACSP) and NOAA's regional climate services program. NACSP is a tri-national initiative to develop and deliver drought-based climate services in order to assist water resource managers, agricultural interests, and other constituents as they prepare for future drought events and build capacity to respond to other climate extremes. The RGB Climate Outlook builds on lessons learned from the Climate Assessment for the Southwest (CLIMAS) Southwest Climate Outlook (PDF, html), La Niña Drought Tracker (PDF, html), the Southern Climate Impacts Policy Program (SCIPP) Managing Drought in the Southern Plains webinar series, the Border Climate Summary (PDF), and Transborder Climate newsletter (PDF) and webinar series. The latter two have been the only regularly occurring bilingual climate information products in the U

  8. Implementation of MAR within the Rio Grande Basin of Central New Mexico, USA

    NASA Astrophysics Data System (ADS)

    Marley, Robert; Blandford, T. Neil; Ewing, Amy; Webb, Larry; Yuhas, Katherine

    2014-05-01

    The U.S. Bureau of Reclamation has identified the Rio Grande basin within Central New Mexico as one of several regions where water supplies are over-allocated and future conflicts over the inadequate resource are highly likely. Local water providers have consistently identified managed aquifer recharge (MAR) as an important tool to provide conjunctive management of surface-water, groundwater, and reclaimed water sources in order to extend the useful life of existing water sources. However, MAR projects have been slow to take root partly due to rigorous demonstration requirements, groundwater quality protection concerns, and ongoing water right uncertainties. At first glance the several thousand meters of unconsolidated basin-fill sediments hosting the regional aquifer appear to provide an ideal environment for the subsurface storage of surplus water. However, the basin has a complex structural and depositional history that impacts the siting and overall effectiveness of MAR systems. Several recharge projects are now in various stages of implementation and are overcoming site specific challenges including source water and ambient groundwater compatibility, low-permeability sediments and compartmentalization of the aquifer by extensive faulting, well clogging, and overall water quality management. This presentation will highlight ongoing efforts of these water providers to develop full-scale recharge facilities. The performance of natural in-channel infiltration, engineered infiltration galleries, and direct injection systems designed to introduce from 500 to 5,000 mega-liters per annum to target intervals present from 150 to 600 meters below ground surface will be described. Source waters for recharge operations include inter-basin transferred surface water and highly treated reclaimed water sources requiring from minor to extensive treatment pre-recharge and post-recovery. Operational complexities have raised concerns related to long-term operation and maintenance

  9. Deformation Along the Rio Grande Rift: Investigating the Spatial and Temporal Distribution of Strain Using GPS

    NASA Astrophysics Data System (ADS)

    Murray, K. D.; Murray, M. H.; Sheehan, A. F.; Nerem, R. S.

    2014-12-01

    Low velocity (<1 mm/yr) extensional environments, such as the Rio Grande rift (RGR) in Colorado and New Mexico, are complex but can provide insights into continental dynamics, tectonic processes, and seismic hazards. We use eight years of measurements from 26 continuous GPS stations across the RGR installed as part of a collaborative EarthScope experiment. We combine this data with regional Plate Boundary Observatory (PBO) and National Geodetic Survey (NGS) CORS GPS stations, and survey-mode data collected on NGS benchmarks to investigate how deformation is distributed across a broad area from the Great Plains to the Colorado Plateau. The data from over 150 stations are processed using GAMIT/GLOBK, and time series, velocities, strain rates are estimated with respect to realizations of a stable North America reference frame, such as NA12. This study extends our previous analysis, based on 4 years of data, which found an approximately uniform 1.2 nanostrain/yr east-west extensional strain rate across the entire region that was not concentrated on the narrow surface expression of the rift. We expand on this previous work by using a denser network of GPS stations and analyzing longer time series, which reduce horizontal velocity uncertainties to approximately 0.15 mm/yr. We also improve the accuracy of the estimated velocity uncertainties by robustly characterizing time-correlated noise. The noise models indicate that both power-law and flicker noise are present in the time series along with white noise. On average, power law noise constitutes about 90% of the total noise in the vertical component and 60% in the horizontal components for the RGR sites. We use the time series, and velocity and strain-rate estimates to constrain spatial and temporal variations in the deformation field in order to locate possible regions of strain localization and detect transient deformation signals, and to address some of the kinematic and dynamic issues raised by the observation that a

  10. Leptospirosis in Rio Grande do Sul, Brazil: An Ecosystem Approach in the Animal-Human Interface

    PubMed Central

    Schneider, Maria Cristina; Najera, Patricia; Pereira, Martha M.; Machado, Gustavo; dos Anjos, Celso B.; Rodrigues, Rogério O.; Cavagni, Gabriela M.; Muñoz-Zanzi, Claudia; Corbellini, Luis G.; Leone, Mariana; Buss, Daniel F.; Aldighieri, Sylvain; Espinal, Marcos A.

    2015-01-01

    Background Leptospirosis is an epidemic-prone neglected disease that affects humans and animals, mostly in vulnerable populations. The One Health approach is a recommended strategy to identify drivers of the disease and plan for its prevention and control. In that context, the aim of this study was to analyze the distribution of human cases of leptospirosis in the State of Rio Grande do Sul, Brazil, and to explore possible drivers. Additionally, it sought to provide further evidence to support interventions and to identify hypotheses for new research at the human-animal-ecosystem interface. Methodology and findings The risk for human infection was described in relation to environmental, socioeconomic, and livestock variables. This ecological study used aggregated data by municipality (all 496). Data were extracted from secondary, publicly available sources. Thematic maps were constructed and univariate analysis performed for all variables. Negative binomial regression was used for multivariable statistical analysis of leptospirosis cases. An annual average of 428 human cases of leptospirosis was reported in the state from 2008 to 2012. The cumulative incidence in rural populations was eight times higher than in urban populations. Variables significantly associated with leptospirosis cases in the final model were: Parana/Paraiba ecoregion (RR: 2.25; CI95%: 2.03–2.49); Neossolo Litolítico soil (RR: 1.93; CI95%: 1.26–2.96); and, to a lesser extent, the production of tobacco (RR: 1.10; CI95%: 1.09–1.11) and rice (RR: 1.003; CI95%: 1.002–1.04). Conclusion Urban cases were concentrated in the capital and rural cases in a specific ecoregion. The major drivers identified in this study were related to environmental and production processes that are permanent features of the state. This study contributes to the basic knowledge on leptospirosis distribution and drivers in the state and encourages a comprehensive approach to address the disease in the animal