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Sample records for california sur mexico

  1. Benthic marine algae of Loreto Bay, Baja California Sur, Mexico

    OpenAIRE

    Sánchez Rodríguez, Ignacio; Aguilar-Rosas, L.E.; R Aguilar-Rosas

    2010-01-01

    Ten sites in the Loreto Bay, Baja California Sur, Mexico, were sampled seasonally during 1996 and 1997, in the center zone of the Gulf of California. The collections of the species was manually in the intertidal and subtidal (3 m, SCUBA) zone in the localities distributed in the bay and surroun ding islands. A total of 62 taxa of benthic marine algae were determined. Rhodophyceae was represen ted by 62 species, Phaeophyceae by 15 species and Chlorophyceae by 7 species. The families with best ...

  2. Identifying recharge from tropical cyclonic storms, Baja California Sur, Mexico.

    Science.gov (United States)

    Eastoe, Christopher J; Hess, Greg; Mahieux, Susana

    2015-04-01

    Groundwater in the Todos Santos watershed in southern Baja California, and throughout the peninsula south of latitude 28°N, has values of (δ18 O‰, δD‰) ranging between (-8.3, -57) and (-10.9, -78). Such negative values are uncharacteristic of the site latitude near the sea level. Altitude effects do not explain the isotope data. Tropical depressions originating along the Pacific coast of North America yield rain with isotopic depletion; rain from these weather systems in southern Arizona commonly has δ18O values50 mm) at least once every 2 to 3 years, and along the Pacific coast between Jalisco and Oaxaca. © 2014, National Ground Water Association.

  3. Stratigraphy of Reforma Caldera, Baja California Sur, Mexico

    Science.gov (United States)

    García Sánchez, L.; Macias, J. L.; Osorio, L. S.; Pola, A.; Avellán, D. R.; Arce, J. L.; Saucedo, R.; Sánchez, J. M.; García-Tenorio, F.; Cisneros, G.; Reyes-Agustín, G.; Cardona, S.; Jimenez, A.

    2015-12-01

    The Reforma caldera is located at ~35 km to the northwest of Santa Rosalía in the central part of the Baja California peninsula. It has 10 km in diameter and a maximum height of 1200 masl in the center and between 100 and 500 masl in its slopes. Reforma is within a tectonic zone affected by two fault systems: A NW-SE normal fault system linked to the opening of the Gulf of California, and a NNW-SSE and NW-SE strike-slip fault system associated with an active Riedel system. Reforma was built upon Cretaceous granites that outcrop at the caldera center, Miocene to Pliocene volcano-sedimentary rocks of the Comondú group, and Miocene marine sediments of the Santa Rosalía basin. On top of these rocks outcrop at least four submarine to subaerial ignimbrites interbedded with marine fossiliferous beds and the lower Pleistocene deposits associated to the Reforma caldera. These deposits are formed by a ignimbrite that shifts to different lithofacies that change gradually their welding, here dubbed basal, transitional, intermediate, and upper (all of then enriched in black fiammes), followed by a pumice-rich, white fiammes, and vitrophyre lithofacies, which are distributed around the 9 km wide caldera and have been associated to the caldera formation episode. Deposits related to post-caldera volcanism are andesite-basaltic lava flows erupted along the caldera rim through localized feeding dikes and andesitic and rhyolitic domes, and scoria cinder cones exposed inside and outside the caldera. On top of these deposits rest the middle Pleistocene Aguajito caldera deposits.

  4. Characteristics regarding the consumer of giant squid from Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Liliana Enriqueta Montaño Méndez

    2015-01-01

    Full Text Available The catch of the giant squid (Dosidicus gigas, represents de second fishing activity most important in volume in Baja California Sur, Mexico; is an essential specie not only at the state level but at the pacific and even the national level. Mexico occupies in the world the eight level in the production of squid, but the national consumption, even though the low price of the product and the high nutritional level, is approximately 0.53 kg per year, very low compared to countries like Japan, Korea and Spain (average consumption per capita is of 3.5 kg . In this context, the objective of this article is to caracterize the sudcalifornia consumer preference; determine the buying habits and the consumption; and also to establish the market areas of the squid in Baja California Sur, which allows the introduction of actions for its commercialization, in order to strengthen the market of this product and its general activity. This is why in 2012 a questioner of 1066 consumers was distribute around the five counties of the state, according to the population density. The results indicate that the principal motive why there is not consumption is the difficulty to find places where to buy it, together with the problems of cooking it. Also, it can be seen the high level of ignorance the consumer has regarding the nutritional level this food has. For this reason, future strategies for the commercialization must be focus on better distribution and new form of presenting this product which facilitates its preparation and consumption, and at the same time create campaign which increase awareness of the nutrition level this product has.

  5. Reconnaissance geologic map of the Loreto and part of the San Janier quadrangles, Baja California Sur, Mexico

    Science.gov (United States)

    McLean, Hugh

    1988-01-01

    The Loreto area of Baja California Sur, Mexico, contains a diverse association of igneous, sedimentary, and metasedimentary rocks exposed in the foothills and arroyos between the Sierra La Giganta and Gulf of California. The Loreto area was selected for this study to examine the possible relation of the marine rocks to the opening of the Gulf of California, and to determine the stratigraphic and structural relations between basement rocks composed of granitic and prebatholithic rocks and overlying Tertiary (mainly Miocene) sedimentary and volcanic rocks, and by a sequence of Pliocene marine and nonmarine sedimentary rocks. The Pliocene marine rocks lie in a structural depression informally called here, the Loreto embayment. This geologic map and report stem from a cooperative agreement between the U.S. Geological Survey and the Consejo de Recursos Minerales of Mexico that was initiated in 1982.

  6. The artisanal elasmobranch fishery of the Pacific coast of Baja California Sur, Mexico, management implications

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    Sergio R. Ramirez-Amaro

    2013-09-01

    Full Text Available Artisanal fisheries in Mexico account for approximately 40% of the total national catch. In 2009, Baja California Sur (BCS had the second largest catch of elasmobranchs on the Mexican Pacific coast. This paper characterizes and describes the artisanal elasmobranch fishery of Pacific coast of BCS from 2000 to 2010. Sixty artisanal camps were documented, of which 45 targeted elasmobranchs, using primarily gillnets and longlines. We identified 52 elasmobranch species. Gillnetting accounted for 73.5% of the fishing effort and most frequently captured Rhinobatos productus, Mustelus henlei and Myliobatis californica. Longline fishing accounted for 26.5% of effort, most frequently capturing Prionace glauca and Isurus oxyrinchus. The prevalence of juveniles of several species (e.g., Cephaloscyllium ventriosum, Galeorhinus galeus, Isurus oxyrinchus, and Myliobatis californica within landings suggests that fishing effort may be opportunistically directed at breeding or nursery areas. Despite the dominance of species with wide distributions, we observed a significant biogeographic pattern in the abundance of some species relative to Bahia Magdalena. Results of the present study will be useful to detect changes in the structure of commercially exploited elasmobranch populations, and to provide useful indications for management purposes.

  7. Hybrid system of generating electricity, solar eolic diesel San Juanico, Baja California Sur, Mexico; Sistema hibrido de generacion electrica, eolico solar diesel San Juanico, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Huerta, Javier [Comision Federal de Electricidad, La Paz, Baja California Sur (Mexico); Johnston, Peter [Technology Development, Arizona (United States); Napikoski, Chester [Generation Engineering, Arizona (United States); Escutia, Ricardo [Comision Federal de Electricidad, Baja California Sur (Mexico)

    2000-07-01

    The Comision Federal de Electricidad (CFE), and the northamerican electric company Arizona Public Service (APS), made an agreement of collaboration to develop a project of generating electricity with the use of renewable resources. The premises that where agreed on are the following: 1. Focus the project a rural community. 2. The cost of the whole project should be lower than compared to the interconnection to a conventional system. 3. Acceptance of the community, and the governmental authorities. 4. Sustentability of the operation of the system. Several technical and economical analysis where done, such as the evaluation of the solar and eolic resources, study of the environmental impact, negotiation agreements so it would be possible to obtain de economical resources from Niagara Mohawk (NIMO), and the USAID, all of this thru the supervising of the Sandia National Laboratories. After the anemometric and solar radiation measures where made, it was considered that the community of San Juanico, en Baja California Sur, Mexico, was the most feasible one, it was necessary also to consider the aspects of logistics, socials, size of the community and as a detonator for the economic activities of tourism and fishing. The APS formulated the executive project in accordance with the recommendations of the different areas of CFE. The project consists basically in the installation of 10 wind generators of 10 Kw, a battery bank for 432 KWh, plus a diesel generator for emergencies of 80 Kw. Besides the civil and electromechanical installation. It was necessary to involve the community in the knowledge and followup of the project form it's, considering that this factor would be essential, so it could be successful. Lamps of low consumption where installed on the houses and street lightning, to optimize the system. The patronato that is a civil association of the community, is in charge of the administration of the system, it receives support from personnel of CFE. The income

  8. An application of neural network in geophysical prospecting. Electrical resistivity at Las Virgenes geothermal field, Baja California Sur, Mexico; Una aplicacion de las redes neuronales a la prospeccion geofisica. Resistividad electrica en las Tres Virgenes, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Palma Guzman, Sergio Hugo [Comision Federal de Electricidad, Morelia, Michoacan (Mexico)

    2000-12-01

    The technology of the neural network is presented with geophysical focus in the Las Virgenes geothermal field, Baja California Sur, Mexico. The results obtained when extrapolating the associative data of the prospecting magnetoteluria and Vertical Electric Sounding, on the area of the geothermal wells to the rest of the area, allows to classify zones of interest for the geothermal exploitation. Also, the use of these associative parameters with the information of the stabilized temperature of the wells, they allow to predict temperatures for the rest of the area. [Spanish] Se presenta una aplicacion de la tecnologia de las redes neuronales con enfoque geofisico en el campo geotermico de Las Virgenes, Baja California Sur, Mexico. Los resultados obtenidos al extrapolar los datos asociativos de las prospecciones geoelectricas de magnetoteluria y sondeos electricos verticales, en la zona de los pozos geotermicos al resto del area, permiten clasificar zonas de interes para la explotacion geotermica. Tambien, la utilizacion de estos parametros asociativos con la informacion de la temperatura estabilizada de los pozos, permiten predecir temperaturas para la misma area.

  9. Seasonal food habits of bobcats (Lynx rufus) in subtropical Baja California Sur, Mexico

    OpenAIRE

    Delibes, M.; Blázquez, M.C.; Estrella, Ricardo R.; Zapata, Sonia C.

    1997-01-01

    The annual and seasonal diet of the bobcat (Lynx rufus) was determined from analysis of 188 feces in the Cape region of Baja California, Mexico, an arid zone with numerous subtropical elements in its flora and fauna. Bobcats fed mainly on lagomorphs, which reached 74% of occurrence, followed by rodents (40%), reptiles (15%), and birds (12%). No seasonal variations were observed. The results were consistent with those of studies elsewhere, indicating that bobcats still rely upon lagomorphs for...

  10. MT data modelling at Las Tres Virgenes, Baja California Sur, Mexico, geothermal zone. Modelado de datos magnetotelurgicos en el campo geotermico de Las Tres Virgenes, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Palma Guzman, Sergio Hugo (Departamento de Exploracion, Gerencia de Proyectos Geotermoelectricos de la Comision Federal de Electricidad, Morelia (Mexico))

    1998-01-15

    An interpretation of MT soundings at the Las Tres Virgenes, Baja California Sur, Mexico, geothermal project, was conducted, to actualize the geoelectric model of the reservoir, with the support provided by new drilling data. MT data were collected during the Comision Federal de Electricidad 1992 and 1994 campaigns. The use of apparent resistivity maps, tipper and apparent profiles lets us to identify TE and TM modes, as well as the lateral variations related to structural geology changes. These results were used to prepare sections based on Bostick inversion of TE mode of each sounding. Results were correlated to lithology reported by recent exploratory drilling. MT comprehensive studies let us delineate the reservoir limits, and the main geologic structures related to geothermal fluids production.

  11. Biocenosis de la comunidad bentónica en la Laguna Guerrero Negro, Baja California Sur, México: caracterización espacio-temporal/Biocenosis of benthic community in Guerrero Negro Lagoon, Baja California Sur, Mexico: spatio-temporal characterization

    National Research Council Canada - National Science Library

    María Verónica Morales-Zárate; Alfredo Zayas-Álvarez; César A Salinas-Zavala; Arminda Mejía-Rebollo

    2016-01-01

      In order to know and characterize the benthic marine community at Guerrero Negro Lagoon, Baja California Sur, Mexico, a monitoring during six months were conducted, sampling 10 stations every month...

  12. Key species and impact of fishery through food web analysis: A case study from Baja California Sur, Mexico

    Science.gov (United States)

    Rocchi, Marta; Scotti, Marco; Micheli, Fiorenza; Bodini, Antonio

    2017-01-01

    Ecosystem-Based Management (EBM) aims to support the protection of natural ecosystems and to improve economic activities. It requires considering all of the actors interacting in social-ecological systems (e.g., fish and fishers) in the understanding that their interplay determines the dynamic behavior of the single actors as well as that of the system as a whole. Connections are thus central to EBM. Within the ecological dimension of socio-ecological systems, interactions between species define such connections. Understanding how connections affect ecosystem and species dynamics is often impaired by a lack of data. We propose food web network analysis as a tool to help bridge the gap between EBM theory and practice in data-poor contexts, and illustrate this approach through its application to a coastal marine ecosystem in Baja California Sur, Mexico. First, we calculated centrality indices to identify which key (i.e., most central) species must be considered when designing strategies for sustainable resource management. Second, we analyzed the resilience of the system by measuring changes in food web structure due to the local extinction of vulnerable species (i.e., by mimicking the possible effect of excessive fishing pressure). The consequences of species removals were quantified in terms of impacts on global structural indices and species' centrality indices. Overall, we found that this coastal ecosystem shows high resilience to species loss. We identified species (e.g., Octopus sp. and the kelp bass, Paralabrax clathratus) whose protection could further decrease the risk of potential negative impacts of fishing activities on the Baja California Sur food web. This work introduces an approach that can be applied to other ecosystems to aid the implementation of EBM in data-poor contexts.

  13. Analysis of sportfishing match rates of striped marlin (Tetrapturus audax) at Cabo San Lucas, Baja California Sur, Mexico, and their relation to sea surface temperature

    OpenAIRE

    Ortega García, Sofía; Klett Traulsen, A; Ponce Díaz, Germán

    2003-01-01

    Cabo San Lucas, Baja California Sur, Mexico, is the main sportfishing location for striped marlin, with a mean annual catch rate of 0.6 fish per fishing trip. In the present study, the interannual and seasonal variation of sportfishing catch rates from 1990 to 1999, and their relationship to mean monthly sea surface temperatures were analysed. Although interannual variation was not significant, the seasonal effect showed significant differences, with highest average catch rates in winter, and...

  14. Can the Adoption of Desalination Technology Lead to Aquifer Preservation? A Case Study of a Sociotechnical Water System in Baja California Sur, Mexico

    OpenAIRE

    Jamie McEvoy

    2015-01-01

    There is growing concern about the sustainability of groundwater supplies worldwide. In many regions, desalination—the conversion of saline water to freshwater—is viewed as a way to increase water supplies and reduce pressure on overdrawn aquifers. Using data from reports, articles, interviews, a survey, and a focus group, this paper examines if, and how, the adoption of desalination technology can lead to aquifer preservation in Baja California Sur (BCS), Mexico. The paper outlines existing ...

  15. Geochemistry of a Tertiary sedimentary phosphate deposit: Baja California Sur, Mexico

    Science.gov (United States)

    Piper, D.Z.

    1991-01-01

    The San Gregorio Formation in Baja California Sur, a phosphate-enriched sedimentary unit of late Oligocene to early Miocene age, has been analyzed in two areas (La Purisima and San Hilario) for its chemical composition (major oxides, Cu, Cd, Cr, Co, V, and rare-earth elements - REE) and isotopic composition (??18O and ??13C). A detrital and a marine component were determined from major oxides. The detrital component consists of an unaltered volcanic-ash fraction and a terrigenous clay-silt fraction. The marine component, which accumulated initially as biogenic and hydrogenous material, is now present as opal-A, opal-CT, CaCO3, organic matter, and an authigenic phosphate fraction, mostly pelletal and composed of the carbonate-fluorapatite mineral francolite. The minor elements have been partitioned into these components by assuming a constant composition for the two detrital fractions. The composition of the marine component of minor elements can then be interpreted by assuming that the stoichiometry of the original accumulating organic matter was equal to that of modern plankton. The Cu and Cd contents in the marine component of all rocks require that the seawater-derived fractions of these two metals were supplied to the seafloor solely by organic matter. Enrichments of Cr and V at both sites required an additional marine input. On the basis of their geochemistry in the modern ocean, Cr and V could have precipitated, or been adsorbed, onto settling particles from an O2 minimum zone in which the O2 content was low enough to promote denitrification rather than oxygen respiration. An enrichment of the REE, now within the apatite fraction, resulted from their adsorption onto particulates also in the O2 minimum zone and to the dissolution and alteration of biogenic phases (predominantly silica) within the sediment. Co and Fe2O3 show no enrichment above a detrital contribution. The ??18O-values of apatites from the La Purisima site are heavier than those of apatites

  16. Comparative analysis of the reproductive strategy of lion's paw scallop Nodipecten subnodosus in Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Marco A Angel-Dapa

    2015-07-01

    Full Text Available The reproductive strategy of lion's paw scallop Nodipecten subnodosus was evaluated in a culturing system in Bahía Tortugas, Baja California Sur, Mexico during an annual cycle, comparing its response with data previously reported at other localities. High frequencies of ripe gonads throughout the year indicate that reproduction was continuous, with two main ripening/spawning events: July-September and December-March. A continuous breeding is also reported for the species in Bahía Magdalena, Bahía Juncalito, and Bahía de Los Angeles. These eutrophic areas are Biological Active Centers where gametogenesis appears to be regulated by the energy taken from recently ingested food following an opportunistic strategy. However, the digestive gland index decreased and the muscle indices increased during one of the breeding peaks, suggesting that some stored reserves are also used to sustain gametogenesis (conservative strategy partially. High incidences of atretic oocytes are likely associated with atypical daily variations in water temperature from May through September (12 to 33°C, or with stressful conditions in the culturing system in summer. Despite this, the culturing system set in Bahía Tortugas appears beneficial for a continuous reproduction of N. subnodosus.

  17. Seasonal diet composition of Fundulus lima (Cyprinodontiformes: Fundulidae in two oasis systems of Baja California Sur, Mexico

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    Dinora Acosta Zamorano

    2011-12-01

    Full Text Available Fundulus lima inhabits river drainage systems and is threatened after the introduction of cichlids in the area. To support conservation programs, the spatial and temporal variation of the diet composition of this endangered killifish, was determined in two oasis systems of Baja California Sur, Mexico (San Ignacio and La Purisima river drainages, during rainy and dry seasons. F. lima was captured by using passive and active capture techniques. A total of 192 stomach contents of F. lima was analyzed. The contribution of each prey item in the diet composition was quantified by means of the indices of occurrence frequency (% OF, numerical (%N and volume (%V percentages. The relative importance of each prey item was determined according to the percentage of the Relative Importance Index (%RII. The similarity of the diet was calculated between hydrological basins (populations combined by basin, seasons (rainy versus dry months, sexes and size classes, by using Schoener’s resource overlap index. We used two ecological indices to determine the type of feeding strategy exhibited by the fish: (1 niche breadth of Levins and (2 proportional similarity of Feisinger. Sand was the most abundant item in the stomach content of killifishes from both drainages (39% and 47%, respectively. Diet composition was similar for both drainages (74% as well as among their respective size classes; however, it was different between sexes. In both drainages, F. lima predated mainly on diatom algae, dipterous and trichopteran larvae, and fish scales during the dry season; while it preferred dipterous larvae, filamentous algae and ostracods in the rainy season. A feeding strategy of opportunist type was exhibited by F. lima during the rainy season, changing to specialist type during the dry season. This information will be the basis for future investigations related to the conservation of this endangered species and its habitat. Rev. Biol. Trop. 59 (4: 1669-1678. Epub 2011

  18. Associations between trace elements and clinical health parameters in the North Pacific loggerhead sea turtle (Caretta caretta) from Baja California Sur, Mexico.

    Science.gov (United States)

    Ley-Quiñónez, César Paúl; Rossi-Lafferriere, Natalia Alejandra; Espinoza-Carreon, Teresa Leticia; Hart, Catherine Edwina; Peckham, Sherwood Hoyt; Aguirre, Alfredo Alonso; Zavala-Norzagaray, Alan Alfredo

    2017-04-01

    This study investigated selected trace elements toxicity in sea turtles Caretta caretta population from Baja California Sur (BCS), Mexico, by analyzing associations among Zn, Se, Cu, As, Cd, Ni, Mn, Pb, and Hg with various biochemical parameters (packed cell volume, leukocytes, and selected blood parameters), and whether their concentrations could have an impact on the health status of sea turtles. Blood samples from 22 loggerhead (C. caretta) sea turtles from BCS, Mexico, were collected for trace elements on biochemistry parameter analyses. Significant associations among trace element levels and the biochemistry parameters were found: Cd vs ALP (R 2 = 0.874, p ˂ 0.001), As vs ALP (R 2 = 0.656, p ˂ 0.001), Mn vs ALP (R 2 = 0.834, p ˂ 0.001), and Ni vs LDH (R 2 = 0.587, p ˂ 0.001). This study is the first report of the biochemical parameters of the North Pacific loggerhead sea turtle (C. caretta) from Baja California Sur, Mexico, and it is the first to observe several associations with toxic and essential trace elements. Our study reinforces the usefulness of blood for the monitoring of the levels of contaminating elements and the results suggest that, based on the associations with health clinical parameters, high levels of Cd and As could be representing a risk to the North Pacific loggerhead population health.

  19. Seasonal diet composition of Fundulus lima (Cyprinodontiformes: Fundulidae in two oasis systems of Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Dinora Acosta Zamorano

    2011-12-01

    Full Text Available Fundulus lima inhabits river drainage systems and is threatened after the introduction of cichlids in the area. To support conservation programs, the spatial and temporal variation of the diet composition of this endangered killifish, was determined in two oasis systems of Baja California Sur, Mexico (San Ignacio and La Purisima river drainages, during rainy and dry seasons. F. lima was captured by using passive and active capture techniques. A total of 192 stomach contents of F. lima was analyzed. The contribution of each prey item in the diet composition was quantified by means of the indices of occurrence frequency (% OF, numerical (%N and volume (%V percentages. The relative importance of each prey item was determined according to the percentage of the Relative Importance Index (%RII. The similarity of the diet was calculated between hydrological basins (populations combined by basin, seasons (rainy versus dry months, sexes and size classes, by using Schoener’s resource overlap index. We used two ecological indices to determine the type of feeding strategy exhibited by the fish: (1 niche breadth of Levins and (2 proportional similarity of Feisinger. Sand was the most abundant item in the stomach content of killifishes from both drainages (39% and 47%, respectively. Diet composition was similar for both drainages (74% as well as among their respective size classes; however, it was different between sexes. In both drainages, F. lima predated mainly on diatom algae, dipterous and trichopteran larvae, and fish scales during the dry season; while it preferred dipterous larvae, filamentous algae and ostracods in the rainy season. A feeding strategy of opportunist type was exhibited by F. lima during the rainy season, changing to specialist type during the dry season. This information will be the basis for future investigations related to the conservation of this endangered species and its habitat. Rev. Biol. Trop. 59 (4: 1669-1678. Epub 2011

  20. Geochemical characteristics of water from the reservoir of the hydrothermal system of Las Tres Virgenes, Baja California Sur, Mexico; Caracteristicas geoquimicas de las aguas del reservorio del sistema hidrotermal actual de Las Tres Virgenes, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Gonalez Partida, Eduardo [Universidad Nacional Autonoma de Mexico (Mexico); Tello Hinojosa, Enrique [Comision Federal de Electricidad (Mexico); Pal Verma, Mahendra [Instituto de Investigaciones Electricas (Mexico)

    2001-03-01

    The Las Tres Virgenes geothermal field is a liquid dominated system. The separated produced by the wells are sodium-chloride type, which is a characteristic of totally equilibrated geothermal brine. The temperature of water-rock interaction in the reservoir is 280 Celsius degrees. the chemical composition of gases corresponds to the one expected in a geothermal environment. The CO{sub 2} is the predominating gas and it is superior in 90% in weight to the total of existing gases. The gas contents is less than 1% in weight, in the case of the wells LV-1 and LV-3. It is also possible to conclude that the gases are in equilibrium with the liquid phase at a temperature of 280 Celsius degrees. With respect to water quality, it is saline, from high to very high and the contents of exchangeable sodium is also very high, resulting in waters not fit for agricultural usage. [Spanish] El yacimiento geotermico de Las Tres Virgenes, en Baja California Sur, Mexico, es un sistema de liquido dominante, en donde el agua separada producida por los pozos presenta un caracter clorurado-sodico caracteristico de una salmuera de origen geotermico totalmente equilibrada. El sistema agua-roca se encuentra en equilibrio a una temperatura de 280 grados centigrados , dicha temperatura son congruentes con las estimadas para las fases gaseosas y liquidas. La composicion quimica de los gases corresponde a la esperada en un ambiente geotermico. El CO{sub 2} es el predominante y es superior a 90% en peso del total de los gases presentes. El contenido de gas es menor de 1% en peso en el caso de los pozos LV-1 y LV-3. Tambien se puede concluir que los gases estan en equilibrio en las fases liquidas a una temperatura de 280 grados centigrados. Con respecto a la calidad del agua, presenta una salinidad de alta a muy alta y el contenido de sodio intercambiable tambien es muy alto, por lo que dichas aguas no son muy aptas para el cultivo.

  1. The ambient acoustic environment in Laguna San Ignacio, Baja California Sur, Mexico.

    Science.gov (United States)

    Seger, Kerri D; Thode, Aaron M; Swartz, Steven L; Urbán, Jorge R

    2015-11-01

    Each winter gray whales (Eschrichtius robustus) breed and calve in Laguna San Ignacio, Mexico, where a robust, yet regulated, whale-watching industry exists. Baseline acoustic environments in LSI's three zones were monitored between 2008 and 2013, in anticipation of a new road being paved that will potentially increase tourist activity to this relatively isolated location. These zones differ in levels of both gray whale usage and tourist activity. Ambient sound level distributions were computed in terms of percentiles of power spectral densities. While these distributions are consistent across years within each zone, inter-zone differences are substantial. The acoustic environment in the upper zone is dominated by snapping shrimp that display a crepuscular cycle. Snapping shrimp also affect the middle zone, but tourist boat transits contribute to noise distributions during daylight hours. The lower zone has three source contributors to its acoustic environment: snapping shrimp, boats, and croaker fish. As suggested from earlier studies, a 300 Hz noise minimum exists in both the middle and lower zones of the lagoon, but not in the upper zone.

  2. Composición del aceite esencial de Tagetes lacera, planta endémica de Baja California Sur, México Composition of essential oil of Tagetes lacera, endemic plant from Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Francisco Díaz-Cedillo

    2012-06-01

    Full Text Available Es escasa la información sobre la biología y química de Tagetes lacera Brand. (Asteraceae, especie endémica de Baja California Sur (BCS, México, que por su porte alto y presencia de aroma es una fuente de aceites esenciales útil para el control de plagas y enfermedades de cultivos agrícolas. A partir de partes aéreas de plantas en floración de T. lacera recolectadas en la sierra de la Laguna, BCS se obtuvo aceite esencial mediante hidrodestilación. Por medio del procedimiento de análisis CG-EM, se identificaron 6 compuestos principales: E-tagetona (26.2%, crisantenona (24.8%, verbenona (22.1%, α-thujeno (20.5%, β-pineno (3.1% y α-pineno (1.9%.It is scarce the background on the biology and chemistry of Tagetes lacera Brand. (Asteraceae, an endemic species from Baja California Sur (BCS, Mexico that considering its plant high and odor is an essential oil source to obtain biopesticides. From aerial parts of plants fully flowered of T. lacera picked in Sierra de la Laguna, BCS, essential oil was obtained by hydrodistillation. Using GC-MS analysis, 6 major compounds were identified: E-tagetone (26.2%, chrysanthenone (24.8%, verbenone (22.1%, α-thujene (20.5%, β-pinene (3.1%, α-pinene (1.9%.

  3. Occurrence of Landslides during the Approach of Tropical Cyclone Juliette (2001) to Baja California Sur, Mexico

    Science.gov (United States)

    Antinao, J.; Farfan, L.

    2012-12-01

    The approach of Tropical Cyclone Juliette to the Baja California Peninsula in September 2001 triggered at least 419 landslides. Most of the landslides were shallow slips and debris slides, of limited areal extent, which were converted rapidly into debris flows to be exported quickly out of the mountain areas towards the lowlands. Main factors affecting landslide occurrence were total storm rainfall and intensity, aspect, geology and vegetation association. Two processes can be distinguished as initiating slope failure. The first process is linked to failures in concave topography, where accumulation of rainfall from exposed bedrock slopes generated excess overland flow that aggregated to generate a 'fire hose' effect on the base of slopes, mobilizing regolith. A second process involved a combination of wind and excess overland flow developed in the more convex or planar upper slopes, where heterogeneous regolith has formed in time following successional changes in vegetation associations along the oak-dry tropical forest ecotone. In this area, wind uprooted trees that dislodged large regolith and bedrock blocks, priming hillslopes for further runoff concentration. From the analysis of historical information, an estimative threshold curve for triggering landslides in this region is sketched. It was also determined that storms like Juliette approach the southern peninsula on average once every 100 years. Denudation estimates are in the higher end of the spectrum for a tectonically passive margin. These estimates should be considered when taking decisions regarding management of water resources in this area through damming of streams. The results emphasize the need for a more detailed representation of the spatial distribution of the rainfall and winds for this mountainous region frequently affected by the passage of tropical cyclones.

  4. Conceptualization of groundwater flow of a coastal arid aquifer using isotopic and chemical tools: La Paz, Baja California Sur, Mexico

    Science.gov (United States)

    Tamez-Melendez, Carol; Hernández-Antonio, Arturo; Mahlknecht, Jürgen

    2016-04-01

    Groundwater from the La Paz coastal aquifer in Baja California Sur, Mexico, is the main source of drinking water for the local population. Due to its proximity to the coast, sea water intrusion is the main factor of salinization of groundwater. Other geochemical processes also affect the quality of the aquifer threating its vulnerability. Forty-seven samples were analyzed for ion chemistry and isotopes. A hierarchical cluster analysis was performed for a better interpretation resulting in three main groups and proved for geographical correspondence. Deuterium and d18O ranged from -82 to -52.1 and from -11.6 to -7 permil, respectively, showing that the main recharge originates in the Sierra el Novillo, flowing toward SE-NW direction and in accordance to deuterium excess (d) high evaporation effects (d>10‰) are mostly in the middle portion of the study area and in El Centenario due to high kinetic isotope fractioning related to elevated temperatures. Hydrogeochemistry analyses demonstrated salinization mainly due to sea water intrusion and in second instance due water-rock interaction, where enrichment of Na+ (ranges from 35.7 to 1089 mg/L-1) was present in some samples probably due to weathering of silicates and/or cation exchange in soils with Ca2+ (27.7 to 658 mg/L-1) at clay-surfaces. High concentrations of NO3-2 (ranges from 1.4 to 48.8 mg/L-1), Cl- (ranges from 54.4 to 2960 mg/L-1) and Na+ show that anthropogenic input is mainly coming from an agricultural area (El Centenario-Chametla) where heavy groundwater extractions are made for irrigational purposes, lowering the groundwater table up to 10 m and consequently promoting upconing and salinity concentrations (NaCl). Carbon-13 and radiocarbon ranged from -12.3 to -9.1‰ and from 29.5 to 100.4 pmC, respectively. Distribution of ages (up to ~5000 years) indicates two flow trends (E-W and SE-NW).

  5. The vascular flora and floristic relationships of the Sierra de La Giganta in Baja California Sur, Mexico La flora vascular y las relaciones florísticas de la sierra de La Giganta de Baja California Sur, México

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    José Luis León de la Luz

    2008-06-01

    Full Text Available The Sierra de La Giganta is a semi-arid region in the southern part of the Baja California peninsula of Mexico. Traditionally, this area has been excluded as a sector of the Sonoran Desert and has been more often lumped with the dry-tropical Cape Region of southern Baja California peninsula, but this classical concept of the vegetation has not previously been analyzed using formal documentation. In the middle of the last century, Annetta Carter, a botanist from the University of California, began explorations in the Sierra de La Giganta that lasted 24 years, she collected 1 550 specimens and described several new species from this area, but she never published an integrated study of the flora. Our objectives, having developed extensive collections in the same area over the past years, are to provide a comprehensive species list and description of the vegetation of this mountain range. We found a flora of 729 taxa, poorly represented in tree life-forms (3.1%, a moderate level (4.4% of endemism, and the dominance of plants in the sampling plots is composed mainly for legume trees and shrubs. Additionally, using a biogeographical approach, we compare our list with other known lists of plants from 5 areas, 3 in the Cape Region, 1 in the Sonoran Desert, and other in the thornscrub area of NW Mexico. We conclude that the La Giganta flora has a mixed composition, primarily made up of plants shared with the lowlands of the southern Cape Region, but also share an important proportion of the flora with the desert mountains of the central peninsula and some with the Sonoran desertscrub of mainland Mexico. Consequently we support that the La Giganta flora is part of a floristic continuum along the volcanic mountains of the southern peninsula that eventually could be considered a new eco-region in the same peninsular land.La sierra de La Giganta se localiza en el estado de Baja California Sur, México, en una región semi-árida. Tradicionalmente, esta

  6. Backscattering and geophysical features of volcanic ridges offshore Santa Rosalia, Baja California Sur, Gulf of California, Mexico

    Science.gov (United States)

    Fabriol, Hubert; Delgado-Argote, Luis A.; Dañobeitia, Juan José; Córdoba, Diego; González, Antonio; García-Abdeslem, Juan; Bartolomé, Rafael; Martín-Atienza, Beatriz; Frias-Camacho, Víctor

    1999-11-01

    Volcanic ridges formed by series of volcanic edifices are identified in the central part of the Gulf of California, between Isla Tortuga and La Reforma Caldera-Santa Rosalı´a region. Isla Tortuga is part of the 40-km-long Tortuga Volcanic Ridge (TVR) that trends almost perpendicular to the spreading center of the Guaymas Basin. The Rosalı´a Volcanic Ridge (RVR), older than TVR, is characterized by volcanic structures oriented towards 310°, following a fracture zone extension and the peninsular slope. It is interpreted that most of the aligned submarine volcanic edifices are developed on continental crust while Isla Tortuga lies on oceanic-like crust of the Guaymas Basin. From a complete Bouguer anomaly map, it is observed that the alignments of gravity highs trending 310° and 290° support the volcanic and subvolcanic origin of the bathymetric highs. Volcanic curvilinear structures, lava flows and mounds were identified from backscattering images around Isla Tortuga and over a 400-m high (Vı´rgenes High), where the TVR and the RVR intersect. A refraction/wide-angle seismic profile crossing perpendicular to the Vı´rgenes High, together with gravity and magnetic data indicate the presence of shallow intrusive bodies presumably of basaltic or andesitic composition. It is inferred that most volcanic edifices along the ridges have similar internal structures. We suggest that the growth of different segments of the ridges have a volcano-tectonic origin. The older RVR lies along the extension of a fracture zone and it probably is associated with Pliocene NE-SW extension.

  7. Variabilidad de la abundancia de zooplancton en Bahía Magdalena Baja California Sur, México (1997-2001 Zooplankton abundance variability in Magdalena Bay, Baja California Sur, Mexico (1997-2001

    Directory of Open Access Journals (Sweden)

    Sergio Hernández-Trujillo

    2010-01-01

    Full Text Available Se analizaron muestras de zooplancton de 16 campañas oceanógraficas, efectuadas en Bahía Magdalena, Baja California Sur, México, entre agosto de 1997 y marzo de 2001. Se identificó un total de 26 grupos taxonómicos, de los cuales los más abundantes y frecuentes fueron copépodos y quetognatos; en 2000-2001 se observó una tendencia a disminuir entre 10 y 20 el número de grupos de zooplancton. La biomasa zooplanctónica y abundancia de copépodos disminuyeron en el periodo de estudio, en contraste con los quetognatos que tuvieron un ligero aumento. Las fluctuaciones de abundancia de zooplancton no estuvieron relacionadas con la concentración de clorofila-α, a diferencia de los máximos de abundancia de zooplancton, que estuvieron asociados a los cambios de la temperatura superficial del mar. El ciclo estacional de la abundancia del zooplancton en Bahía Magdalena, indicó que en invierno el promedió fue mayor de 65.000 ind 100 m-3 , valor que aumentó en primavera a más de 99.000 ind 100 m-3 , se mantuvo en verano alrededor de 100.000 ind 100 m-3 y en otoño descendió rápidamente a casi 40.000 ind 100 m-3.Zooplankton were studied from 16 oceanographic surveys carried out in Magdalena Bay, Baja California Sur, Mexico, between August 1997 and March 2001. Twenty-six taxonomic groups were identified, the most abundant and frequent of which were copepods and chaetognaths. In 2000-2001, the number of zooplankton groups tended to decrease by 10 to 20. Both zooplankton biomass and copepod abundance declined, unlike chaetognaths, which increased slightly. Fluctuations in zooplankton abundance were independent of the chlorophyll-a concentration, whereas the maximum zooplankton abundances were associated with changes in the sea surface temperature. The seasonal zooplankton abundance cycle in Magdalena Bay indicated that, in winter, the averaged was than 65,000 ind 100 m-3 , a value that increased to more than 99,000 ind 100 m-3 in spring

  8. Lunar phase and catch success of the striped marlin (Tetrapturus audax) in sport fishing at Los Cabos, Baja California Sur, Mexico.

    Science.gov (United States)

    Ponce-Díaz, G; Ortega-García, S; Hernández-Vázquez, S

    2003-06-01

    The influence of the lunar phases on the catch-per-unit effort (CPUE) of the striped marlin (Tetrapturus audax) captured by the Cabo San Lucas, Baja California Sur, Mexico sport-fishing fleet from October 1987 to June 1989 was analyzed. The information is from 3,377 fishing trips by 13 vessels that represent about 10% of the fleet. The analysis of the CPUE showed a maximum in January 1988 and a minimum in February 1989. Taking into account the knowledge of the factors that had influence on the fishing success is important in the resource management. No significant difference during the full moon compared with results during other lunar phases was found.

  9. Coastal management at Ojo de Liebre, Baja California Sur

    Science.gov (United States)

    Frederico Salinas-Zavala; Alfredo Ortega-Rubio; Diego Valez-Zamudio; Aradit. Castelanos-Vera

    2000-01-01

    We analyzed the biotic, abiotic, and human components interacting at the coastal zone of the Ojo de Liebre Lagoon, Baja California Sur, Mexico. Using geographic information systems, satellite images, and the main biological, physical, and socioeconomic components, we developed an environmental characterization of the zone. According with the natural features of the...

  10. Geochemistry of Dissolved Trace Metals in the Waters of Bahia Magdalena, Baja California Sur, Pacific Coast, Mexico

    Science.gov (United States)

    Suresh Babu, S.

    2016-12-01

    Forty two samples were acquired from the surface and bottom water profiles along 5 transects spread over Bahia Magdalena lagoon, Baja California Sur to assess the behavior of trace metals in a high influenced upwelling region on the Pacific coast. To elaborate the fate of metals, also the physico-chemical parameters (pH, temperature, salinity, conductivity, dissolved oxygen). Determination of the concentrations of trace metals (Fe, Mn, Cr, Cu, Co, Pb, Ni, Zn, Cd As, Hg) were measured using Atomic absorption spectrometry. The results demonstrated high values of As, Ni and Co which is attributed to the local geology and phosphate deposits. Low values of Fe and Mn are attested to the oxic conditions of the lagoon which are responsible for the oxidation of Fe and Mn. The region witnesses raised temperatures (28.92ºC) and salinities of 35.2 PSU for its arid climatic conditions and high rates of evaporation. In general, the region presented minor quantities of dissolved trace metals due to dispersion and high intense interaction with the open sea. The results were also compared with other studies to understand the enrichment pattern in this side of the pacific coast which experiences various geothermal activities and upwelling phenomenon.

  11. Marine diet and tobacco exposure affects mercury concentrations in pregnant women (I from Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Ramón Gaxiola-Robles

    2014-01-01

    Full Text Available Seafood provides essential polyunsaturated fatty acids (PUFA and other nutrients to pregnant women and their fetus(es while a diet rich in finfish can be a major pathway of monomethyl mercury (MeHg+ exposure. We measured total mercury concentration ([THg] in hair samples provided by 75 women in Baja California Sur (BCS to assess its relationship with age, parity, tobacco smoke exposure, and diet based on survey methodologies. Generalized linear models (GLM were used to explain the possible association of the different variables with [THg] in hair. Median [THg] in hair was 1.52 μg g−1, ranging from 0.12 to 24.19 μg g−1 and varied significantly by segment. Approximately 72% (54/75 of those evaluated exceed 1 μg g−1 [THg] and 8% (6/75 exceed 5 μg g−1 [THg] in hair. Although frequency of fish consumption contributed significantly to explaining hair [THg], fish consumption only explained 43% of [THg] in a GLM incorporating tobacco exposure and body mass index. This study establishes possible relationships among multiple potential sources of exposure and other factors related to [THg] in hair of women in the prenatal period. A more detailed examination of other sources of exposure and factors contributing to [THg] is warranted.

  12. Lunar phase and catch success of the striped marlin (Tetrapturus audax in sport fishing at Los Cabos, Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    G. Ponce-Díaz

    2003-06-01

    Full Text Available The influence of the lunar phases on the catch-per-unit effort (CPUE of the striped marlin (Tetrapturus audax captured by the Cabo San Lucas, Baja California Sur, Mexico sport-fishing fleet from October 1987 to June 1989 was analyzed. The information is from 3 377 fishing trips by 13 vessels that represent about 10 % of the fleet. The analysis of the CPUE showed a maximum in January 1988 and a minimum in February 1989. Taking into account the knowledge of the factors that had influence on the fishing success is important in the resource management. No significant difference during the full moon compared with results during other lunar phases was found.Se analizó la influencia de las fases lunares sobre la captura por unidad de esfuerzo en el marlín rayado (Tetraptus audax capturado por la flota deportiva en Cabo San Lucas, Baja California Sur, desde octubre de 1987 a junio de 1989. La información de 3377 viajes de pesca por 13 embarcaciones que representan cerca de un 10% de la flota. El análisis mostró un máximo en enero de 1988 y un mínimo en febrero de 1989. Tomar en consideración el conocimiento de los factores que tuvieron influencia en el éxito en la pesca es importante en el manejo de los recursos. No se encontró diferencias significativas durante la luna llena comparado con los resultados obtenidos durante las otras fases de la luna.

  13. Fauna de arañas del suelo de una comunidad árida-tropical en Baja California Sur, México Ground surface spider fauna in an arid tropical community in Baja California Sur, Mexico

    OpenAIRE

    María Luisa Jiménez; José Gabriel Navarrete

    2010-01-01

    Se describe la temporalidad y diversidad de arañas del suelo del matorral sarcocaule en la región del Cabo en Baja California Sur. Durante 1991-1992 se realizaron colectas semanales por medio de trampas de caída. Se capturaron 4 322 ejemplares de 53 especies. Las familias con mayor abundancia fueron Miturgidae (42.2%), Oonopidae (23.5%), Caponiidae (8.0%) y Gnaphosidae (7.9%). Las especies más abundantes fueron Syspira tigrina Chamberlin (37.1%); Oonops nov. sp. (13.7%), Scaphiella hespera Ch...

  14. Effects of environmental variability on recruitment and bioeconomic modelling in the Pacific sardine (Sardinops sagax caerulea fishery from Magdalena Bay, Baja California Sur, Mexico

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    Juan Antonio de Anda-Montañez

    2010-03-01

    Full Text Available Ricker's stock-recruitment equation, including the multivariate ENSO index (MEI as an environmental variable, was fitted to data of the Pacific sardine (Sardinops sagax caerulea fishery from Magdalena Bay, Baja California Sur, Mexico. The equation was then incorporated into an age-structured, bioeconomic model. Uncertainty was incorporated by using environmental fluctuations; seven-year projections, equivalent to one sardine generation, were computed. Five management options were considered in the projections: open access, effort at maximum sustainable economic yield (fMSE, catch at maximum sustainable yield (CMSY, equivalent effort level applied in the year 2004 (f2004, and an arbitrary catch quota of 40000 tons (CQ40000. Projection results were summarised by the indicator Net Present Value (NPV of the fishery for the modelled period. The strategies that involved some regulation in the effort level (fMSE and f2004 yielded the largest NPV. On the other hand, the strategies that involved regulation of the catch predicted—in addition to a lower NPV—a substantial increase in the effort to achieve the desired catch level. This study is the first bioeconomic approach for a sardine fishery management plan in this region.

  15. Analysis of drought and desertification by means of aridity indices and the estimation of water gap in Baja California Sur, Northwest Mexico

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    Enrique Troyo Diéguez

    2013-10-01

    Full Text Available In Baja California Sur (BCS, Mexico, dry-semi warm and warm climates prevail associated to an extreme trend of diurnal temperatures and the environmental dryness. In this State, the maximum summer t exceeds 40° C and the minimum varies from 5 to 12° C, with a minimal for the State of 2° C in winter, at the top of the Sierra de La Laguna; only Los Cabos region has a warm humid climate. Because precipitation in the state is low, oscillating from 310 mm in the southern area of the state to 120 mm per year in the northern portion, predictions and scenarios under climate conditions point to an intensification of droughts. The aim of this work was to carry out a comparative analysis of trends of temperature, precipitation and hydro-environmental aridity among contrasting localities of BCS, by means of the application of Aridity Indexes and the determination of the Standardized Water Gap (BHE, through a numerical scale modification of the De Martonne Index. With the values of temperature and precipitation for the different climate change scenarios for four weather stations, the indicators Hydro Environmental Availability Index (IDHA and Hydro Environmental Drought Index (ISHA were calculated to determine their trend and the consequent BHE, an innovative quantification of wáter deficit, which is proposed in this paper. The máximum value of BHE (10 units, indicating prevalence of drought, is observed from February to June in almost the entire state.

  16. Can the Adoption of Desalination Technology Lead to Aquifer Preservation? A Case Study of a Sociotechnical Water System in Baja California Sur, Mexico

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    Jamie McEvoy

    2015-09-01

    Full Text Available There is growing concern about the sustainability of groundwater supplies worldwide. In many regions, desalination—the conversion of saline water to freshwater—is viewed as a way to increase water supplies and reduce pressure on overdrawn aquifers. Using data from reports, articles, interviews, a survey, and a focus group, this paper examines if, and how, the adoption of desalination technology can lead to aquifer preservation in Baja California Sur (BCS, Mexico. The paper outlines existing institutional arrangements (i.e., laws, rules, norms, or organizations surrounding desalination in BCS and concludes that there are currently no effective mechanisms to ensure aquifer preservation. Four mechanisms that could be implemented to improve groundwater management are identified, including: 1 integrated water-and land-use planning; 2 creation of an institute responsible for coordinated and consistent planning; 3 improved groundwater monitoring; and 4 implementation of water conservation measures prior to the adoption of desalination technology. This paper concludes that viewing water technologies, including desalination, as sociotechnical systems—i.e., a set of technological components that are embedded in complex social, political, and economic contexts—has the potential to create a more sustainable human–environment–technology relationship. By assessing desalination technology as a sociotechnical system, this study highlights the need to focus on institutional development and capacity building, especially within local water utilities and urban planning agencies.

  17. New and noteworthy waterfowl records at artificial wetlands from Baja California Sur, Mexico Registros nuevos y sobresalientes de anátidos en humedales artificiales de Baja California Sur, México

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    Roberto Carmona

    2011-06-01

    Full Text Available We present 9 recent records of rare waterfowls in Baja California Sur, all of them in artificial wetlands: 3 freshwater sites and 1 concentration area for a saltworks. We present the first records of the Ross's Goose in the state. The remaining 8 species are: Black-bellied Whistling-Duck (breeding, Fulvous Whistling-Duck, Greater White-fronted Goose, Snow Goose, Cackling Goose, Tundra Swan, Mallard and Hooded Merganser. To this list we added an historical compilation of the records of these species in artificial sites of the state. The artificial wetlands are no replacement for their natural counterparts, they are nevertheless an important part of the region's landscape mosaic. As the records of the present work exemplify, this man-made habitat increases the regional species richness, and should be considered as important areas that need to be protected.Presentamos registros recientes de 9 especies de anátidos raros en Baja California Sur, todos ellos realizados en humedales creados por el hombre: 3 sitios dulceacuícolas y 1 área de concentración para la producción de sal. Se incluyen los primeros registros del ganso de Ross (Chen rossii para el estado. Las 8 especies restantes son: Dendrocygna autumnalis (anidación, D. bicolor, Anser albifrons, Chen caerulesens, Branta hutchinsii, Cygnus columbianus, Anas platyrhynchos y Lophodytes cucullatus. A la lista, agregamos una recopilación histórica de los registros de estas especies en humedales artificiales del estado. Aunque estos sitios no deben sustituir a sus contrapartes naturales, actualmente forman parte del mosaico paisajístico que ofrece la región; adicionalmente, incrementan la riqueza de especies de la región, por lo que es necesario brindarles protección.

  18. General characteristics of the diet of Trachinotus paitensis (Teleostei: Carangidae) from San Ignacio Lagoon, Baja California Sur, Mexico.

    Science.gov (United States)

    Cruz Escalona, V H; Abitia Cárdenas, L A

    2004-03-01

    The food habits of Trachinotus paitensis, in San Ignacio Lagoon B.C.S., Mexico, were investigated. We observed that T. paitensis is carnivorous, feeding mainly on benthic invertebrates (the gastropods Anachis spp., Bittium spp., and the crustacean larvae). We concluded that T. paitensis is an opportunist predator that impacts mainly on epibenthic invertebrates.

  19. General characteristics of the diet of Trachinotus paitensis (Teleostei: Carangidae) from San Ignacio Lagoon, Baja California Sur, Mexico

    OpenAIRE

    Cruz Escalona, V H.; Abitia Cárdenas, L A.

    2014-01-01

    The food habits of Trachinotus paitensis, in San Ignacio Lagoon B.C.S., Mexico, were investigated. We observed that T. paitensis is carnivorous, feeding mainly on benthic invertebrates (the gastropods Anachis spp., Bittium spp., and the crustacean larvae). We concluded that T. paitensis is an opportunist predator that impacts mainly on epibenthic invertebrates. Fueron investigados los hábitos alimenticios de Trachinotus paitensis, en la laguna San Ignacio B.C.S., México. Se observó que T. ...

  20. General characteristics of the diet of Trachinotus paitensis (Teleostei: Carangidae) from San Ignacio Lagoon, Baja California Sur, Mexico

    OpenAIRE

    V.H. Cruz Escalona; L.A. Abitia Cárdenas

    2004-01-01

    The food habits of Trachinotus paitensis, in San Ignacio Lagoon B.C.S., Mexico, were investigated. We observed that T. paitensis is carnivorous, feeding mainly on benthic invertebrates (the gastropods Anachis spp., Bittium spp., and the crustacean larvae). We concluded that T. paitensis is an opportunist predator that impacts mainly on epibenthic invertebratesFueron investigados los hábitos alimenticios de Trachinotus paitensis, en la laguna San Ignacio B.C.S., México. Se observó que T. paite...

  1. Food habits of the silky shark Carcharhinus falciformis (Müller & Henle, 1839) off the western coast of Baja California Sur, Mexico

    OpenAIRE

    Cabrera Chávez, A.A; Galván Magaña, Felipe; Escobar Sánchez, Ofelia

    2010-01-01

    The objective of this study was to establish the trophic niche of the silky shark and to determine the ecological role of this predator in the ecosystem close to Baja California. The trophic spectrum was analyzed from samples taken during summer and autumn (2000–2002) from the fishing camps of Punta Lobos and Punta Belcher on the western coast of Baja California Sur. A total of 263 stomach contents were analyzed (143 with food; 120 empty). The index of relative importance (IRI) showed that at...

  2. General characteristics of the diet of Trachinotus paitensis (Teleostei: Carangidae from San Ignacio Lagoon, Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    V.H. Cruz Escalona

    2004-03-01

    Full Text Available The food habits of Trachinotus paitensis, in San Ignacio Lagoon B.C.S., Mexico, were investigated. We observed that T. paitensis is carnivorous, feeding mainly on benthic invertebrates (the gastropods Anachis spp., Bittium spp., and the crustacean larvae. We concluded that T. paitensis is an opportunist predator that impacts mainly on epibenthic invertebratesFueron investigados los hábitos alimenticios de Trachinotus paitensis, en la laguna San Ignacio B.C.S., México. Se observó que T. paitensis es carnívoro, y se alimenta principalmente de invertebrados bénticos (los gastrópodos Anachis spp., Bittium spp., y larvas de crustáceos. En conclusión esta especie es un depredador oportunista que tiene un impacto principalmente sobre las poblaciones de invertebrados epibénticos

  3. Epiphytic diatoms associated with red mangrove (Rhizophora mangle prop roots in Bahía Magdalena, Baja California Sur, Mexico

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    D.A Siqueiros Beltrones

    2006-06-01

    Full Text Available The first floristic inventory of benthic diatoms is provided for the Bahía Magdalena- Bahía Almejas lagoon system. Samplings were carried out during November of 1999. The oxydized samples were mounted permanently. Eighty six diatom taxa were identified, out of which 59 are new records for the Bahía Magdalena area, and 12 taxa are new for the Baja California peninsula. Taxa recorded previously as rare in other substrata are common or abundant on the epiphytic macroalgae of mangrove prop roots. Other species are mainly epipelic forms, while 24 are commonly found as tychoplankton in the area. Certain taxa appear to be characteristic of mangrove systems in general. Rev. Biol. Trop. 54(2: 287-297. Epub 2006 Jun 01.Se presenta el primer inventario florístico de diatomeas bénticas para el Sistema Lagunar Bahía Magdalena-Bahía Almejas. Se hicieron muestreos en noviembre de 1999. En las muestras oxidadas y montadas permanentemente, se identificaron 86 táxones, de los cuales 59 son nuevos registros para el área de Bahía Magdalena, y 12 son nuevos para la península de Baja California. Táxones previamente registrados como escasos en otros sustratos son comunes o abundantes sobre macroalgas epífitas de raíces primarias de mangle. Otras species son principalmente formas epipélicas, mientras que 24 son constituyentes comunes del ticoplancton del área. Ciertos táxones parecen ser característicos de sistemas de manglar en general.

  4. AUV Mapping and ROV Exploration of Los Frailes Submarine Canyon, Cabo Pulmo National Marine Park, Baja California Sur, Mexico

    Science.gov (United States)

    Troni, G.; Caress, D. W.; Graves, D.; Thomas, H. J.; Thompson, D.; Barry, J. P.; Aburto-Oropeza, O.; Johnson, A. F.; Lundsten, L.

    2015-12-01

    Los Frailes submarine canyon is located at the south boundary of the Cabo Pulmo National Marine Park on the southeast tip of the Baja California Peninsula. During the Monterey Bay Aquarium Research Institute (MBARI) 2015 Gulf of California expedition we used an autonomous underwater vehicle (AUV) to map this canyon from 50 m to 450 m depths, and then explored the canyon with a small remotely operated vehicle (ROV). This three day R/V Rachel Carson cruise was a collaboration with the Center for Marine Biodiversity and Conservation at Scripps Institution of Oceanography and the Centro para la Biodiversidad Marina y la Conservación in La Paz. The MBARI AUV D. Allan B. collected high resolution bathymetry, sidescan, and subbottom profiles of Los Frailes submarine canyon and part of the north Cabo Pulmo deep reef. In order to safely generate a 1-m lateral resolution multibeam bathymetry map in the nearshore high relief terrain, the mapping operations consisted of an initial short survey following the 100-m isobath followed by a series of short, incremental AUV missions located on the deep edge of the new AUV bathymetry. The MBARI Mini-ROV was used to explore the submarine canyon within the detailed map created by the MBARI AUV. The Mini-ROV is a 1.2-m-long, 350 kg, 1,500-m-depth-rated ROV designed and constructed by MBARI. It is controlled by six 600-watt thrusters and is equipped with a high-definition video camera and navigation sensors. This small ROV carries less accurate, lower cost navigation sensors than larger vehicles. We implemented new algorithms to localize combining Doppler velocity log sensor data and low-cost MEMS-based inertial sensor data with sporadic ultra-short baseline position measurements to provide a high accuracy position estimation. The navigation performance allowed us to colocate the ROV video imagery with the 1-m resolution bathymetric map of the submarine canyon. Upper Los Frailes Canyon is rugged and, aside from small sand pockets along

  5. Seismicity, focal mechanisms, and stress distribution in the Tres Virgenes volcanic and geothermal region, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Victor; Munguia, Luis [Centro de Investigacion Cientifica y de Educacion Superior de Ensenada (Mexico)

    2006-01-15

    In October 1993 we carried out a seismic monitoring in the Tres Virgenes volcanic region in order to record the background seismicity associated with the volcanic structures, the geothermal field and the tectonic features of the area. Hypocenters for 257 microearthquakes were located in the volcanic edifices and along the northwest right-lateral, strike-slip La Virgen fault. Focal depths range from close to the Earth surface to about 8 km. Shallow depths occur mainly in the volcanic edifices. Deeper seismic events occurred outside the volcanic area. The duration magnitudes of the located microearthquakes range between 1 and 3. The Vp/Vs ratio and the low-Q values estimated suggest heterogeneous material properties in the volcanic structures mainly toward the El Azufre fault and the El Aguajito Caldera, where hydrothermal activity has been reported. The P- and T-axes of focal mechanisms for 90 microearthquakes suggest that the region is under N-S compression and E-W extension, in agreement with the regional tectonic stress field of the NW-SE right-lateral strike-slip transform fault system of the Gulf of California. [Spanish] En octubre de 1993 se llevo a cabo un monitoreo sismico en la region volcanica Las Tres Virgenes con el proposito de registrar la actividad sismica asociada a las estructuras volcanicas, al campo geotermico y a la tectonica local. Se localizaron 257 microsismos con hipocentros en los edificios volcanicos y a lo largo de la falla de rumbo, lateral derecha conocida como falla La Virgen. La profundidad focal de los sismos varia desde los muy cercanos a la superficie de la Tierra hasta los 8 km. Las profundidades someras ocurren principalmente en los edificios volcanicos. Los sismos mas profundos ocurren fuera del area volcanica. La magnitud de duracion de los microsismos localizados varia entre 1 y 3. La razon Vp/Vs y los valores bajos de Q que se estimaron en la zona sugieren un material con propiedades heterogeneas bajo las estructuras

  6. Transformations of Mangrove Forests in Bahia Magdalena, Baja California Sur, Mexico: Two Decade Results Based on Landsat Imageries

    Science.gov (United States)

    Suresh Babu, S.; Abdul Rahaman, S.; Muthushankar, G.; Jonathan, M. P.

    2014-12-01

    Mangrove forests which thrive along the tropical and subtropical regions are the most productive ecosystems in the world with a wide range of ecological and economical services to mankind. With the rapid urbanization across the globe, these forests tend to be destroying at an alarming rate. The area of concern for this study, Bahia Magdalena is very important for the economy of the state as nearly 50% of the artisan fisheries are established in the mangrove zone. Henceforth this study is an attempt for a regional assessment and to accurately quantify the mangroves using LANDSAT imageries for over two decades in Bahia Magdalena, Baja California. Satellite imageries from the year 1986 through 2014 were analysed to assess the prolonged changes taking place in and around the mangrove reserve. Using the estimates of land use/cover for all the years, the spatio - temporal data was validated using ArcGIS software. The results revealed that the spatial extent of mangroves are decreasing until 2005 due to the developmental plans such as tourism, shrimp farming and establishment of industries in this part of the country. During the past 10 years (~ after 2005) there is no much change in the area extent of mangrove reserves due to afforestation and conservation efforts. Thus the unbiased dataset generated may be widely used for an improved understanding of the role of mangrove forests in the socio economic aspects, protection from natural disasters, identify possible areas for conservation, restoration and rehabilitation; and improve estimates of the amount of carbon stored in mangrove vegetation and the associated marine environment. Keywords: Mangroves, LANDSAT, Bahia Magdalena, México.

  7. Distribución espacial y temporal de aves playeras (Orden: Charadriiformes en Laguna San Ignacio, Baja California Sur, México Temporal and spatial distribution of shorebirds (Charadriiformes at San Ignacio Lagoon, Baja California Sur, Mexico

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    Luis Francisco Mendoza

    2013-03-01

    Full Text Available Con la pérdida o degradación de humedales han declinado las poblaciones de algunas especies tales como las aves playeras. En vista de que ha crecido el interés internacional por los estudios ecológicos sobre estas especies, se determinó la abundancia, distribución y riqueza espacio-temporal de las aves playeras en Laguna San Ignacio, Península de Baja California. Se realizaron 12 censos mensuales (octubre 2007-septiembre 2008 en el perímetro interno de la laguna; la cual se dividió en cuatro zonas, dos al norte y dos al sur. Temporalmente las abundancias menores se presentaron en mayo (1 585 aves y las mayores en octubre (47 410. Las especies más abundantes fueron: el picopando canelo (Limosa fedoa; 55% de los registros totales, el playero occidental (Calidris mauri; 23% y el playero pihuiuí (Tringa semipalmata; 10%. Estas especies fueron más abundantes en otoño. El picopando canelo y el playero pihuiuí estabilizaron sus números en invierno y primavera y estuvieron presentes en verano en bajos números, el playero occidental mostró oscilaciones notorias. Se presentan los primeros reportes del playero rojizo del Pacifico (Calidris canutus roselaari para la zona. La riqueza y abundancia estuvieron influenciadas temporal y espacialmente por las aves migratorias. Las mayores abundancias se presentaron al sur de la laguna, probablemente por la disponibilidad del alimento. Los resultados presentes permitieron incluir al área en la Red Hemisférica de Reservas para las Aves Playeras como sitio de importancia internacional.Baja California Peninsula has several wetlands that represent important ecosystems for shorebirds. San Ignacio Lagoon is one of these sites, and supports 10% of the total abundance of shorebirds reported in this Peninsula. Since there is few information about this group in this area, we studied spatial and temporal changes in abundance and distribution of shorebirds in San Ignacio Lagoon. For this, we conducted twelve

  8. Fauna de arañas del suelo de una comunidad árida-tropical en Baja California Sur, México Ground surface spider fauna in an arid tropical community in Baja California Sur, Mexico

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    María Luisa Jiménez

    2010-08-01

    Full Text Available Se describe la temporalidad y diversidad de arañas del suelo del matorral sarcocaule en la región del Cabo en Baja California Sur. Durante 1991-1992 se realizaron colectas semanales por medio de trampas de caída. Se capturaron 4 322 ejemplares de 53 especies. Las familias con mayor abundancia fueron Miturgidae (42.2%, Oonopidae (23.5%, Caponiidae (8.0% y Gnaphosidae (7.9%. Las especies más abundantes fueron Syspira tigrina Chamberlin (37.1%; Oonops nov. sp. (13.7%, Scaphiella hespera Chamberlin (7.8% y Tarsonops sternalis Chamberlin (5.2%, que constituyeron el 63.7% del total de individuos. Gnaphosidae fue la más rica en especies (11, seguida por Salticidae (7. La riqueza de especies fue constante durante todo el año, con un ligero ascenso en el verano (29 y una ligera disminución en el invierno (24. La diversidad por estación del año se mantuvo en un intervalo de H'= 3.3 -3.7. La abundancia relativa se incrementó en primavera y otoño. La mayor riqueza específica se encontró en otoño. La abundancia relativa y la diversidad de arañas se pueden considerar altas, a pesar del fuerte dominio de la familia Miturgidae. En la mayoría de las especies, la distribución mostró una marcada estacionalidad.Seasonal distribution, specific richness, and diversity of xeric shrub ground spiders were studied at a site in the Cape Region. Weekly collections of spiders were made in 1991-1992 using pit-fall traps. We captured 4 322 specimens in 53 families. Families with the highest number of individuals were: Miturgidae (42% Oonopidae (23.5%, Caponiidae (8.0%, and Gnaphosidae (7.9%. The most abundant species were Syspira tigrina Chamberlin (37.1%; Oonops nov. sp. (13.7%, Scaphiella hespera Chamberlin (7.8%, and Tarsonops sternalis Chamberlin (5.2%, representing 63.7% of the total specimens captured. Gnaphosidae was the richest in species (11 followed by Salticidae (7. Species richness was nearly constant during all the year, with a small increase in

  9. [Length, body weight and sex of the golden Coryphaena hippurus (Perciformes: Coryphaenidae), of the littoral of Sinaloa, Nayarit and Baja California Sur, Mexico].

    Science.gov (United States)

    Madrid, J V; Beltrán-Pimienta, R

    2001-01-01

    Dolphin fish population data were recorded from landings in Sinaloa, Nayarit and Baja Califonia Sur, Mexico, in 1997. Of 3,211 organisms, only 2,812 produced complete biometric data. The maximal length and weight were 192 cm and 30 kg. The three sampling sites and the climatic periods also were associated with different size (P < 0.05). The covariate analysis of weight and length relationships indicated significative differences (P < 0.05) for total data and by sex. Condition factor was higher throughout the study period in Mazatlán, and the variation was higher, in the spring. The sexual ratio was in Mazatlán constant, while there were more males in Nayarit in the fall and the spring and in Los Cabos in the spring. There may be population differences, between the central mexican Pacific Coast and the Peninsula of Baja data.

  10. Active Crustal Deformation in the Area of San Carlos, Baja California Sur, Mexico as Shown by Data of Local Earthquake Sequences

    Science.gov (United States)

    Munguía, Luis; González-Escobar, Mario; Navarro, Miguel; Valdez, Tito; Mayer, Sergio; Aguirre, Alfredo; Wong, Victor; Luna, Manuel

    2016-10-01

    We analyzed earthquakes of sequences that occurred at different times near San Carlos, a town of approximately 5000 inhabitants. The seismic sequences happened during March-April 1989, October 2000-June 2001, and 5-15 February 2004 at about 200 km west of the Pacific-North America plate boundary. The strong shaking from initial earthquakes of the first two sequences prompted the installation of temporary seismic stations in the area. With data recorded by these stations, we found an earthquake distribution that is consistent with the northwest segment of the Santa Margarita fault. Both the focal depth, that seemed to increase in E-NE direction, and a composite fault-plane solution, obtained from polarity data of the small earthquakes, were also consistent with the main characteristics of that fault. We also found that our normal-faulting mechanism (east side down) was quite similar to centroid moment tensor solutions for earthquakes with M w 5.4 and 5.3 that occurred in the area in February 2004. It is likely, then, that these larger earthquakes also occurred along the Santa Margarita Fault. To get some insight into the regional stress pattern, we compared the above mechanisms with mechanisms reported for other earthquakes of the Pacific margin of Baja California Sur and the Gulf of California regions. We observed that focal mechanisms of the two regions have T axes of stress that plunge sub horizontally in E-NE average direction. The corresponding P axes have N-NW average trend, but for the Pacific earthquakes these axes plunge at angles that are ~35° larger than those for the Gulf earthquakes. These more vertically inclined P axes of compressive stress mean substantial oblique fault motions. The mixture of oblique and strike-slip components of fault motions, as the focal mechanisms show, confirms a transtensional stress regime for the region. Before this research, we knew little about the seismicity and styles of faulting in the area. Now we know that

  11. Tectono-stratigraphic evolution of the Comondú Group from Bahía de La Paz to Loreto, Baja California Sur, Mexico

    Science.gov (United States)

    Drake, William R.; Umhoefer, Paul J.; Griffiths, Alexis; Vlad, Ann; Peters, Lisa; McIntosh, William

    2017-11-01

    The late Oligocene to mid-Miocene volcanic and volcaniclastic rocks of the Comondú Group are well exposed along the Main Rift Escarpment of Baja California Sur from the Bahía de La Paz region to Bahía Concepción. New mapping and stratigraphic analysis of the Comondú Group from Bahía de La Paz to Loreto reveal facies trends and correlations that form the foundation for a continuous stratigraphic framework for the Comondú Group along a 300 km-long transect on the eastern coast of the Baja California peninsula. Broad but distinct lithostratigraphic trends, alluvial fan facies, and volcanic and volcaniclastic facies record an overall coarsening-upwards package that includes ignimbrite deposits within increasingly proximal alluvial fan deposits, both derived from the east. Geochronology of the unit, including 32 isotope ages and 12 previously unpublished 40Ar/39Ar ages, provide the timing of four main increasingly proximal depositional events. Non-marine sandstone, defining the base of the Comondú Group, was first deposited between 26 Ma and 24 Ma. Emplacement of rhyolitic ignimbrites initiated between 24 Ma and 23 Ma and marked a westward expansion of volcanic activity affiliated with the Sierra Madre Occidental ignimbrite sequences in southern Sinaloa, western Durango, and northern Nayarit. A change in volcanism occurred at 19 Ma to 18 Ma with more ignimbrites, increased intermediate compositions, and the appearance of local vents and proximal volcanic facies. A final localized change of volcanism occurred from 14 to 12 Ma in the Loreto area with an increase of proximal alluvial fan deposits and local volcanoes in the Upper Comondú Group. The bulk of the Upper Comondú Group is absent south of the Loreto area and has either been removed by erosion as a source for the Magdalena Fan in the Pacific Ocean, or was focused primarily in the Loreto area and northward. We use a pre-rift tectonic reconstruction of the Gulf of California to align broad stratigraphic

  12. El cardón Pachycereus pringlei, nuevo hospedero para Scyphophorus acupunctatus (Coleoptera: Curculionidae en Baja California Sur, México The giant cardon cactus Pachycereus pringlei, a new host for Scyphophorus acupunctatus (Coleoptera: Curculionidae in Baja California Sur, Mexico

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    Yolanda Maya

    2011-09-01

    Full Text Available Se presenta el primer registro de una cactácea, Pachycereus pringlei (cardón, especie dominante del matorral xerófilo de la península de Baja California, como hospedero de Scyphophorus acupunctatus (picudo del agave. A partir de observaciones y la recolección de individuos adultos y larvas, se pudo establecer que el picudo del agave causa al menos 3 tipos de daño al cardón: 1, barrenado en la región apical de los brazos por los adultos; 2, consumo de la médula de los brazos por las larvas, que puede ser tan extenso que ocasiona la muerte del cardón y 3, perforaciones en diversos sitios de los brazos, por donde las larvas eliminan los desechos, que pueden ser entrada de otros parásitos o que por lo menos dejan cicatrices en forma de tumor. El éxito de este insecto en el cardón podría representar una amenaza para las poblaciones naturales de esta cactácea e incluso para los servicios ambientales de los matorrales xerófilos.This is the first record of a cactus, Pachycereus pringlei (giant cardon, which is a dominant species of the xerophyllous scrub in the Baja California peninsula, as a host of Scyphophorus acupunctatus (agave weevil. Based on observations and the sampling of adults and larvae, it was possible to establish that this weevil causes at least 3 types of damage to the cardon: 1, drilling of the tip of the branches by adults; 2, consumption of the branch medulla by larvae, which can be so extended that could cause the cardon’s death, and 3, perforations in the branches, used by larvae to eliminate wastes, that could serve as entrance to other pests and remain as tumor-like scars. The success that this insect seems to have by using the giant cardon cactus as host represents a threat to its natural populations and even to the xerophillous scrub environmental services.

  13. Mapping variations in weight percent silica measured from multispectral thermal infrared imagery - Examples from the Hiller Mountains, Nevada, USA and Tres Virgenes-La Reforma, Baja California Sur, Mexico

    Science.gov (United States)

    Hook, S.J.; Dmochowski, J.E.; Howard, K.A.; Rowan, L.C.; Karlstrom, K.E.; Stock, J.M.

    2005-01-01

    Remotely sensed multispectral thermal infrared (8-13 ??m) images are increasingly being used to map variations in surface silicate mineralogy. These studies utilize the shift to longer wavelengths in the main spectral feature in minerals in this wavelength region (reststrahlen band) as the mineralogy changes from felsic to mafic. An approach is described for determining the amount of this shift and then using the shift with a reference curve, derived from laboratory data, to remotely determine the weight percent SiO2 of the surface. The approach has broad applicability to many study areas and can also be fine-tuned to give greater accuracy in a particular study area if field samples are available. The approach was assessed using airborne multispectral thermal infrared images from the Hiller Mountains, Nevada, USA and the Tres Virgenes-La Reforma, Baja California Sur, Mexico. Results indicate the general approach slightly overestimates the weight percent SiO2 of low silica rocks (e.g. basalt) and underestimates the weight percent SiO2 of high silica rocks (e.g. granite). Fine tuning the general approach with measurements from field samples provided good results for both areas with errors in the recovered weight percent SiO2 of a few percent. The map units identified by these techniques and traditional mapping at the Hiller Mountains demonstrate the continuity of the crystalline rocks from the Hiller Mountains southward to the White Hills supporting the idea that these ranges represent an essentially continuous footwall block below a regional detachment. Results from the Baja California data verify the most recent volcanism to be basaltic-andesite. ?? 2005 Elsevier Inc. All rights reserved.

  14. Use of small reactors as an alternative to supply electricity to Baja California Sur; Uso de reactores pequenos como alternativa de suministro de electricidad para Baja California Sur

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, G.; Portes, E.; Ramirez, J. R. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Ortega, G., E-mail: gustavo.alonso@inin.gob.mx [Comision Federal de Electricidad, Rio Rodano No. 14, 06500 Ciudad de Mexico (Mexico)

    2016-09-15

    The state of Baja California Sur (Mexico) does not form part of the national interconnected electrical system of the country, reason why is local its electrical power supply; one of the alternatives to cover future demands is the use of gas-based combined cycles, which presents the additional problem of including a high price for gas transportation in its costs. In order to reduce total costs, including investment, fuels and operation and maintenance in the operation of the Baja California Sur state electricity system in the coming years, mainly due to the estimated natural gas cost order of $11.50 dollars per million BTU, a proposal is presented to reduce the costs of the electrical system by replacing the necessary combined cycles with the new Small Modular Reactor type nuclear reactors, this alternative is economically competitive. (Author)

  15. [Polyplacophoran communities (Mollusca: Polyplacophora) at Bahia de La Paz, Baja California Sur, México].

    Science.gov (United States)

    García Ríos, Cedar I; Alvarez Ruiz, Migdalia

    2007-03-01

    Eight species of polyplacophorans have been reported from La Bahia de la Paz, Baja California Sur, Mexico. We add Lepidochitona beanii, Chaetopleura lurida, Stenoplax limaciformis, S. mariposa, Lepidozona clathrata, L. serrata and Acanthochitona arragonites, increasing the known number of species to 15. Ordination analysis of five chiton communities at the site suggests a correlation of wave exposure to species composition and diversity: communities with intermediate wave exposure have more species (richness) and higher diversity (Shannon's index).

  16. Origins of late- Pleistocene coastal dune sheets, Magdalena and Guerrero Negro, from continental shelf low-stand supply (70-20 ka), under conditions of southeast littoral- and eolian-sand transport, in Baja California Sur, Mexico

    Science.gov (United States)

    Peterson, Curt D.; Murillo-Jiménez, Janette M.; Stock, Errol; Price, David M.; Hostetler, Steve W.; Percy, David

    2017-10-01

    Shallow morpho-stratigraphic sections (n = 11) in each of two large coastal dune sheets including the Magdalena (7000 km2) and Guerrero Negro (8000 km2) dune sheets, from the Pacific Ocean side of Baja California Sur, Mexico, have been analyzed for dune deposit age. The shallow morpho-stratigraphic sections (∼2-10 m depth) include 11 new TL and 14C ages, and paleosol chronosequences, that differentiate cemented late Pleistocene dune deposits (20.7 ± 2.1 to 99.8 ± 9.4 ka) from uncemented Holocene dune deposits (0.7 ± 0.05 to at least 3.2 ± 0.3 ka). Large linear dune ridges (5-10 m in height) in the dune sheet interiors trend southeast and are generally of late Pleistocene age (∼70-20 ka). The late Pleistocene dune deposits reflect eolian transport of marine sand across the emerged continental shelf (30-50 km southeast distance) from low-stand paleo-shorelines (-100 ± 25 m elevation), which were locally oriented nearly orthogonal to modeled deep-water wave directions (∼300° TN). During the Holocene marine transgression, onshore and alongshore wave transport delivered remobilized shelf-sand deposits to the nearshore areas of the large dune sheets, building extensive barrier islands and sand spits. Submerged back-barrier lagoons generally precluded marine sand supply to dune sheet interiors in middle to late Holocene time, though exceptions occur along some ocean and lagoon shorelines. Reactivation of the late Pleistocene dune deposits in the dune sheet interiors lead to generally thin (1-3 m thickness), but widespread, covers of Holocene dune deposits (0.41 ± 0.05 to 10.5 ± 1.6 ka). Mechanical drilling will be required to penetrate indurated subsoil caliche layers to reach basal Pleistocene dune deposits.

  17. Residential tourism and migration of foreign retirees in Mexico: A case study on the environmental impacts and public services in Baja California Sur

    Directory of Open Access Journals (Sweden)

    Diego Armando Casas-Beltrán

    2013-07-01

    Full Text Available Migration of foreign retirees in Mexico has increased, especially in Los Cabos, where settlements trailer type are increasing and are moving into rural coastal areas of high ecological value, without the knowledge of impacts that may result. Thus the aim of this paper is to contribute to the understanding of this type of settlement, by documenting a case study, the characteristics of their community, their environmental impacts and implications for the provision of public services. We conclude that the town will become a short-term retreat site, because while it does not have high densities, its environmental implications are significant and broad coverage. Its current demand for services is minimal, but may cause conflicts in the future, especially with the water

  18. Mining activities and arsenic in a Baja California Sur watershed

    Science.gov (United States)

    Alejandro Naranjo-Pulido; Alfredo Ortega-Rubio; Baudillo Acost-Vargas; Lia Rodriguez-Mendez; Marcos Acevedo-Beltran; Cerafina Arguelles-Mendez

    2000-01-01

    Mining is one of the most important sources of income for the Baja California Sur state. This state is the second most important area for mineral (gold, silver, copper) and non-mineral (salt) mining activities in the Mexican Republic. In the San Antonio-El Triunfo region, mineral-mining activities flourished during the 19th century. Tons of debris containing a high...

  19. Migration of As, Hg, Pb, and Zn in arroyo sediments from a semiarid coastal system influenced by the abandoned gold mining district at El Triunfo, Baja California Sur, Mexico.

    Science.gov (United States)

    Marmolejo-Rodríguez, Ana Judith; Sánchez-Martínez, Martha Alicia; Romero-Guadarrama, Juan Armando; Sánchez-González, Alberto; Magallanes-Ordóñez, Víctor René

    2011-08-01

    Extensive waste deposits (tailings) and ash from the ignition oven of the abandoned gold mine of mining district El Triunfo (MD-ET) in Baja California Sur, Mexico have released trace elements into the sediments of the Hondo-Las Gallinas-El Carrizal arroyo, which connects to the Pacific Ocean through an evaporitic basin. Migration of these elements through the arroyo is mainly caused by winds or tropical hurricanes that occur sporadically during the summer and cause the otherwise dry arroyo to overflow. To evaluate the concentration and distribution of the elements As, Hg, Pb, and Zn along the 48 km arroyo, surface sediments were collected from 26 sites, ranging from close to the MD-ET to the mouth of the arroyo at the Pacific Ocean. Concentrations in tailings and ash were for As 8890 and 505 000 mg kg(-1); for Hg 0.336 and 54.9 mg kg(-1); for Pb 92,700 and 19,300 mg kg(-1); and for Zn 49,600 and 1380 mg kg(-1). The average of the Normalized Enrichment Factor (Av-NEF) in surface sediments, calculated using background levels, indicates that the sediments are severely contaminated with As and Zn (Av-NEF = 22), Pb (Av-NEF = 24) and with a moderate contamination of Hg (Av-NEF = 7.5). The anthropogenic influence of those elements is reflected in the arroyo sediments as far as 18 km away from the MD-ET, whereas the samples closest to the discharge into the Pacific Ocean show a natural to moderate enrichment for As and Zn and low or no enrichment for Hg and Pb. A principal components analysis identified four principal components that explained 90% of the total variance. Factor 1 was characterized by a high positive contribution of the anthropogenic source elements, especially As, Pb, and Zn (37%), whereas Factor 2 was strongly correlated with the oxy-hydroxides of Fe and Mn (27%). Factor 3 was correlated with Li (16%) and Factor 4 with Al (10%), which indicates more than one source of lithogenic composition, though they played a minor role in the distribution of the

  20. The 2006 Bahía Asunción Earthquake Swarm: Seismic Evidence of Active Deformation Along the Western Margin of Baja California Sur, Mexico

    Science.gov (United States)

    Munguía, Luis; Mayer, Sergio; Aguirre, Alfredo; Méndez, Ignacio; González-Escobar, Mario; Luna, Manuel

    2016-10-01

    The study of the Bahía Asunción earthquake swarm is important for two reasons. First, the earthquakes are clear evidence of present activity along the zone of deformation on the Pacific margin of Baja California. The swarm, with earthquakes of magnitude M w of up to 5.0, occurred on the coastline of the peninsula, showing that the Tosco-Abreojos zone of deformation is wider than previously thought. Second, the larger earthquakes in the swarm caused some damage and much concern in Bahía Asunción, a small town located in the zone of epicenters. We relocated the larger earthquakes with regional and/or local seismic data. Our results put the earthquake sources below the urban area of Bahía Asunción, at 40-50 km to the north of the teleseismically determined epicenters. In addition, these new locations are in the area of epicenters of many smaller events that were located with data from local temporary stations. This area trends in an E-W direction and has dimensions of approximately 15 km by 10 km. Most earthquakes had sources at depths that are between 4 and 9 km. A composite focal mechanism for the smaller earthquakes indicated right-lateral strike-slip motion and pure-normal faulting occurred during this swarm. Interestingly, the ANSS earthquake catalog of the United States Geological Survey (USGS) reported each one of these faulting styles for two large events of the swarm, with one of these earthquakes occurring 2 days before the other one. We associate the earthquake with strike-slip mechanism with the San Roque Fault, and the earthquake with the normal faulting style with the Asunción Fault. However, there is need of further study to verify this possible relation between the faults and the earthquakes. In addition, we recorded peak accelerations of up to 0.63 g with an accelerometer installed in Bahía Asunción. At this site, an earthquake of M w 4.9 produced those high values at a distance of 4.1 km. We also used the acceleration dataset from this site

  1. Manejo de un sitio de anidación para la conservación de Sternula antillarum (Charadriiformes: Laridae en Baja California Sur, México Nesting site management for Sternula antillarum (Charadriiformes: Laridae conservation in Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Edgar Amador

    2008-06-01

    Full Text Available El gallito marino menor (Sternula antillarum es una especie sujeta a protección especial, que anida en colonias pequeñas en hábitats costeros. Las mareas altas son un problema para la anidación de S. antillarum en Baja California Sur, pues causan la inundación de algunas colonias. Para reducir el impacto potencial del flujo de marea alta sobre los nidos, se elevó 20 cm el nivel del suelo por medio de una plataforma elevada construida con llantas de desecho rellenas y cubiertas de arena. La ocupación de este sitio por S. antillarum se monitoreó durante las temporadas reproductivas de 1990, y de 2002 a 2005. Las mareas altas no afectaron los nidos establecidos sobre la plataforma y la densidad de nidos sobre ella fue mayor que la que hubo en el terreno natural de la planicie costera adyacente. Este método de manejo del hábitat de anidación de S. antillarum es una buena alternativa en los sitios con riesgo por flujo de marea.The Least Tern (Sternula antillarum is a threatened seabird species that breeds in small colonies on coastal habitats. High tides constitute a problem for their reproduction in Baja California Sur, since they cause flooding of some colonies. To reduce the potential impact of high tides on the nests, the level of the ground was elevated by 20 cm, through an elevated platform that was built by using discarded tires filled and covered with sand. The occupation of this site by Least Terns was monitored during the breeding seasons of 1990 and from 2002 to 2005. High tides did not affect the nests established on the platform and density of nests on this platform was higher than on the natural adjacent mudflat area. This nesting habitat management method for the Least Tern is an appropriate alternative for those sites affected by high tides.

  2. Vertebrados terrestres registrados mediante foto-trampeo en arroyos estacionales y cañadas con agua superficial en un hábitat semiárido de Baja California Sur, México Terrestrial vertebrates recorded by camera traps in areas with seasonal streams and creeks of superficial waters in a semiarid habitat of Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Erika Mesa-Zavala

    2012-03-01

    Full Text Available Los cuerpos de agua superficial (CAS permanentes o efímeros (pozas, tinajas, escurrimientos, etc. que se encuentran en depresiones del terreno, como arroyos y cañadas, son soporte fundamental para el ecosistema en zonas áridas. Mediante el uso de cámaras-trampa, en este estudio se identifican especies de vertebrados terrestres silvestres presentes en 4 sitios con agua superficial, en el extremo sur de la sierra El Mechudo, Baja California Sur, y se analiza el uso de los CAS por las especies en los periodos de actividad. En cada sitio se caracterizó el hábitat (topografía, vegetación y agua. Los 4 sitios mostraron diferencias en sus características ambientales. Se identificaron 41 especies de vertebrados terrestres (3 reptiles, 31 aves y 7 mamíferos. Se encontraron también varias especies de murciélagos que no fueron identificadas. La riqueza de especies y frecuencia de visita fue diferente en cada sitio. Con excepción de 3 especies de mamíferos, el horario de actividad fue similar en los 4 sitios. La presente investigación aporta información sobre la importancia de los CAS en zonas semiáridas, describiendo el hábitat, las especies y su comportamiento, elementos básicos para la conservación y manejo de los recursos naturales.Permanent or ephemeral water ponds (puddles, catchments, drains, and so on located on ground depressions, such as streams and creeks, are a fundamental support for ecosystems in dry areas. This study identified the species of native terrestrial vertebrates in 4 sites in the southernmost part of the Sierra El Mechudo, B.C.S., including how such species use these bodies of water based on the periods of species activity. Habitats were characterized in 4 sites (topography, vegetation, and water sources; camera-traps were placed around water ponds from March to October 2007. The 4 sites differed in their environmental characteristics. Overall, there were 41 species of terrestrial vertebrates (3 reptiles, 31

  3. Seasonal changes in a fish assemblage associated with mangroves in a coastal lagoon of Baja California Sur, Mexico Cambios estacionales de la comunidad de peces asociada a zonas de manglar en una laguna costera de Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Jesús Rodríguez-Romero

    2011-07-01

    Full Text Available The fish assemblage in a coastal lagoon with mangroves known as "Rancho Bueno" was determined and associated with environmental parameters. We used an experimental otter trawl net to catch the fish, and 62 fish species were identified from 48 genera and 30 families. The most abundant species were: Etropus crossotus, Eucinostomus gracilis, Paralabrax maculatofasciatus, Sphoeroides annulatus, and Eucinostomus dowii. The water temperature changed seasonally, being warm from July through December and cold from January through June. We found more fish species during the warm season than during the cold season. The southern area of the coastal lagoon had the highest diversity and species richness. The small size of the fishes registered confirms the ecological role of coastal lagoons as nursery areas that offer protection and feeding to commercially important fish near Bahía Magdalena, Mexico.Se determinó la estructura de peces asociada a factores ambientales en una laguna costera con manglar denominada "Rancho Bueno". Se utilizó una red de arrastre experimental para la captura y se identificaron 62 especies de peces de 48 géneros y 30 familias. Las especies más importantes fueron Etropus crossotus, Eucinostomus gracilis, Paralabrax maculatofasciatus, Sphoeroides annulatus y Eucinostomus dowii. La temperatura del agua varió estacionalmente, siendo cálida de julio a diciembre y fría de enero a junio. Se registró un mayor número de especies de peces durante la época cálida comparada con la época fría. La zona sur de la laguna costera presentó una mayor diversidad y riqueza específica. El menor tamaño de los peces registrados, confirma el papel ecológico de las lagunas costeras, consideradas como áreas de crianza las cuales proporcionan protección y alimentación a los peces de importancia comercial cerca de Bahía Magdalena, México.

  4. Comunidades de quitones (Mollusca: Polyplacophora de la Bahía de La Paz, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Cedar I García Ríos

    2007-03-01

    Full Text Available A las ocho especies de poliplacóforos registradas en Bahía de la Paz, Baja California Sur, México, o cerca de ella, agregamos a Lepidochitona beanii, Chaetopleura lurida, Stenoplax limaciformis, S. mariposa, Lepidozona clathrata, L. serrata y Acanthochitona arragonites. El análisis de las comunidades estudiadas usando técnicas de ordenación sugiere que podría relacionarse la exposición al oleaje con la riqueza y la diversidad de especies. La comunidad recolectada en condiciones intermedias de exposición al oleaje presentó mayor número de especies y mayor diversidad de acuerdo con el índice de Shannon.Polyplacophoran communities (Mollusca: Polyplacophora at Bahía de La Paz, Baja California Sur, México. Eight species of polyplacophorans have been reported from La Bahía de la Paz, Baja California Sur, Mexico. We add Lepidochitona beanii, Chaetopleura lurida, Stenoplax limaciformis, S. mariposa, Lepidozona clathrata, L. serrata and Acanthochitona arragonites, increasing the known number of species to 15. Ordination analysis of five chiton communities at the site suggests a correlation of wave exposure to species composition and diversity: communities with intermediate wave exposure have more species (richness and higher diversity (Shannon’s index. Rev. Biol. Trop. 55 (1: 177-182. Epub 2007 March. 31.

  5. Dynamic Ambient Noise Model Comparison with Point Sur, California, In Situ data

    National Research Council Canada - National Science Library

    Leigh, Charlotte V; Eller, Anthony I

    2006-01-01

    ... 1.0 against both in situ ambient noise (AN) measurements collected in 1998 offshore Point Sur, California, and against predicted AN spectrum levels computed with the Ambient Noise Directionality Estimation System (ANDES...

  6. Multidrug-resistant tuberculosis among patients in Baja California, Mexico, and Hispanic patients in California.

    Science.gov (United States)

    Bojorquez, Ietza; Barnes, Richard F W; Flood, Jennifer; López-Gatell, Hugo; Garfein, Richard S; Bäcker, Claudia E; Alpuche, Celia; Vinetz, Joseph M; Catanzaro, Antonino; Kato-Maeda, Midori; Rodwell, Timothy C

    2013-07-01

    We sought to compare prevalence and determinants of multidrug-resistant tuberculosis (MDR-TB) between tuberculosis patients in Baja California, Mexico, and Hispanic patients in California. Using data from Mexico's National TB Drug Resistance Survey (2008-2009) and California Department of Public Health TB case registry (2004-2009), we assessed differences in MDR-TB prevalence comparing (1) Mexicans in Baja California, (2) Mexico-born Hispanics in California, (3) US-born Hispanics in California, and (4) California Hispanics born elsewhere. MDR-TB prevalence was 2.1% in Baja California patients, 1.6% in Mexico-born California patients, 0.4% in US-born California patients, and 2.7% in Hispanic California patients born elsewhere. In multivariate analysis, previous antituberculosis treatment was associated with MDR-TB (odds ratio [OR] = 6.57; 95% confidence interval [CI] = 3.34, 12.96); Mexico-born TB patients in California (OR = 5.08; 95% CI = 1.19, 21.75) and those born elsewhere (OR = 7.69; 95% CI = 1.71, 34.67) had greater odds of MDR-TB compared with US-born patients (reference category). Hispanic patients born outside the US or Mexico were more likely to have MDR-TB than were those born within these countries. Possible explanations include different levels of exposure to resistant strains and inadequate treatment.

  7. Desarrollo, identidad cultural y turismo en los oasis de Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Alexandra Sauvage

    2013-01-01

    Full Text Available This article provides an analysis of the integration of San Miguel and San José de Comondú to the process of economic globalization lived in Baja California Sur, in northwest Mexico. These rural communities are located in one of the largest oasis in the arid Baja California peninsula and face the risks of cultural commodification from the growth of the real estate and tourism sectors. In a context of diffuse integration to new markets and a weak local community involvement in the initiatives to foster economic growth, without a cultural policy that involves comundeños in defining their own heritage and the benefits of its use, the goal of local development attached to the recent public policies is questionable. We propose that a cultural policy should form the backbone of the development programmes now being elaborated, so as to articulate regional development needs with cultural heritage conservation, seeking to avoid the simple commodification of local traditions and recognizing the role of the local community in (redefining their cultural values.

  8. Islas Marias Archipelago, Mexico. A Missing Piece to Reconstruct the Paleoposition of Baja California

    Science.gov (United States)

    Schaaf, P. E.; Pompa, V.; Hernandez, T.; Weber, B.; Solis, G.; Villanueva, D.; Perez-Venzor, J.

    2011-12-01

    Paleopositions for southern Baja California peninsula have yielded controversial models over the past 30 years. Mainly based on paleomagnetic data many hypotheses place Baja at lower paleolatitudes in front of southern Mexico or Central America with subsequent northward translations. Other models suggest minor, if any, northward displacements with respect to continental Mexico combined with clockwise rotations. Lithological, geochemical, and geochronological similarities for southern Baja California and Puerto Vallarta (western Mexico Pacific margin) igneous rocks seem to confirm the latter model. To further prove this model we have mapped and collected rocks from Maria Madre, the largest island of the Islas Marias archipelago, located in the mouth of the Gulf of California. In an area of only 145 square kilometers, metamorphic basements rocks (ortho and migmatitic gneisses), highly deformed metasediments, granitoids, acid to intermediate volcanic sequences, and a cover with gently folded marine sediments are exposed. The basement complex with gneisses and metasediments, including garnet-bearing paragneiss and calc silicates, as well as the granodioritic-tonalitic intrusives display an extraordinary accordance with similar units observed in the Los Cabos Block (LCB) of Baja California Sur. Furthermore, U-Pb zircon ages of 162 and 170 Ma for the basement gneisses and of 80 Ma for the granitoids have been reported also from the LCB. Additionally, upper Cretaceous intrusive ages are well known from the Puerto Vallarta batholith in Jalisco and Nayarit, mainland Mexico. Geochemical and isotopic data as well as Nd model ages confirm a magmatic consanguinity of LCB, Islas Marias, and Puerto Vallarta granitoids. The volcanic units of Maria Madre Island include ignimbrites and effusive dacitic-rhyolithic rocks, which can be correlated to the Sierra Madre Occidental province and the Comundú Formation of Baja California. Age determinations are under work to confirm this

  9. Learning processes and productive modernization of learning in agriculture from northwestern Mexico: Cases of commercial agriculture of the coast of Hermosillo, Sonora and organic agriculture of the southern zone of Baja California Sur

    Directory of Open Access Journals (Sweden)

    Abel O. Villa Rodríguez

    2013-01-01

    Full Text Available The process of open markets has created import changes in the Mexican agriculture sector, very much noted in the so called crop pattern, the institutional frame that guides the agro–productive commercial relationships and trade organization. The agriculture in the Northwest region, particularly La Costa de Hermosillo in the State of Sonora and southern Baja in Baja Peninsula, shows a big transformation. This corresponds to Global Production Networks (gpn, a vertical integration with intensive extraterritorial interaction resulting in a process of productive escalation that favors; learning and the creation of new competitive capabilities indispensable to comply with high standards in international markets. These capabilities are reflected in improvements in product quality, productive efficiency and the development of new functions for the players involved in the production and trade of produce. It also reflects the transition to more sophisticated productive units where players are located in other territories. This study focuses on analyzing the roll of gpn in the transformation of the agricultural sector in the northwest region of Mexico, particularly the process that took place in modernizing both places.

  10. Variabilidad espacio temporal de la clorofila a y la productividad primaria en el sistema frontal de Baja California Sur

    OpenAIRE

    López Alcántar, Dalia Guadalupe

    2014-01-01

    La concentración de Clorofila a (Cla-a) ha sido utilizada como un indicador de la biomasa fitoplanctónica, el fitoplancton es responsable de la asimilación de CO2 en el océano, proceso conocido como productividad primaria (PP). El Sistema Frontal de Baja California Sur (SFBCS) se encuentra al sur del Sistema de la Corriente de California frente a las costas de Baja California Sur (20º y 24º N, 107º y 117º W). Pese a que forma parte de uno de los ecosistemas más productivos del mundo, esta sis...

  11. Remagnetization of Cretaceous forearc strata on Santa Margarita and Magdalena Islands, Baja California Sur: Implications for northward transport along the California margin

    Science.gov (United States)

    Hagstrum, Jonathan T.; Sedlock, Richard L.

    1998-12-01

    Paleomagnetic data for two sections of Cretaceous forearc strata with different structural attitudes on Santa Margarita and Magdalena Islands in Baja California Sur, Mexico, indicate that these rocks have been remagnetized, probably during the late Cenozoic. The in situ paleomagnetic directions, however, are similar to data from other Cretaceous rocks on peninsular California with unexpectedly shallow inclinations and easterly declinations. These data have been interpreted as indicating either northward tectonic transport (10°-15° of latitude) and clockwise rotation (>20°) or compaction shallowing of magnetic inclinations in sedimentary rocks combined with southwestward tilting of plutonic rocks. The available paleomagnetic data for Cretaceous forearc strata in southern and Baja California can be divided into three groups: (1) sections with normal-polarity magnetizations that fail fold tests and are remagnetized, (2) sections with normal-polarity magnetizations with no or inconclusive fold tests that may or may not be remagnetized, and (3) sections with both normal-and reversed-polarity intervals where pervasive remagnetization has not occurred. Other rocks of the Mesozoic Great Valley Group, Coast Range ophiolite, and Franciscan Complex in California also have secondary magnetizations with directions similar to younger geomagnetic field directions. Although these widespread remagnetizations could have variable local causes, we propose regional burial and uplift, related to changes in subduction parameters, as a possible explanation. Two episodes of remagnetization are apparent: one in the Late Cretaceous and a second in the late Cenozoic. On the other hand, the unremagnetized and apparently reliable data from sedimentary and plutonic rocks on the Baja Peninsula consistently indicate northward translation (14° ± 3°) and clockwise rotation (29° ± 8°) with respect to North America since the Late Cretaceous.

  12. PIXE analysis of cave sediments, prehispanic paintings and obsidian cutting tools from Baja California Sur caves

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, J.; Oliver, A.; Dacal, A.; Ruvalcaba, J.L.; Cruz, F.; Ortiz, M.E. (Inst. de Fisica, Univ. Nacional Automoma Mexico, Mexico City (Mexico)); Vinas, R. (Inst. de Investigaciones Antropologicas, Univ. Nacional Autonoma Mexico, Mexico City (Mexico))

    1993-04-01

    Elemental PIXE analysis of cave sediments, minerals, pigments of the prehispanic paintings and obsidian cutting tools from caves in Baja California Sur has been carried out with a 0.7 MeV proton beam. The elements analysed in this sample set (Al to Co) provide an idea of the environment of the caves. The obsidian data analysis suggests that the human communities who made these painting used more than one obsidian source to manufacture cutting tools. (orig.).

  13. Population size and exploitation of giant squid (Dosidicus gigas D'Orbigny, 1835 in the Gulf of California, Mexico

    Directory of Open Access Journals (Sweden)

    Enrique Morales-Bojórquez

    2001-03-01

    Full Text Available The most important landing sites of the giant squid (Dosidicus gigas D´Orbigny, 1835 fishery in the Gulf of California, Mexico are Guaymas, in Sonora and Santa Rosalía, in Baja California Sur. An increase in the species biomass resulted in increased landings, ranging from 6, 200 tons in 1994 to 140,000 tons in 1996. The development of a management strategy for this fishery based on the proportional escapement has been suggested. This necessitates the estimation of the population size when the fishing season begins in order to determine the amount of fishing effort. Weekly catch and effort data were reported from October 1995 to March 1996 for three fleets operating in the Gulf of California. The population size estimated using a maximum likelihood model was 82,000 tons with a proportional escapement of 66%.

  14. Preliminary geologic studies of Sierra El Aguajito (Baja California, Mexico): a resurgent-type caldera

    Science.gov (United States)

    Garduño-Monroy, V. H.; Vargas-Ledezma, H.; Campos-Enriquez, J. O.

    1993-12-01

    Geologic field studies conducted in the Quaternary volcanic field of Tres Virgenes (State of Baja California Sur, Mexico) revealed the existence of a resurgent caldera. The caldera's eruptive products, the Aguajito sequence, overlie the products of the nearby Reforma caldera (Reforma sequence) whose youngest products have already been dated as Quaternary. The rim of the Aguajito caldera is inferred by the existence of an arcuate alignment of rhyolitic domes. The mean diameter of this subcircular feature is 10 km. The volume of its mapped acidic products is a minimum of 10 km 3. Several horizons within the sequence contain shells. K/Ar dates of the ignimbrites and domes of El Aguajito formation confirm that the unit are Pleistocene. The detailed stratigraphy also shows the evolution of a marine regression partly related to the caldera.

  15. 75 FR 64681 - Pistachios Grown in California, Arizona, and New Mexico; Continuance Referendum

    Science.gov (United States)

    2010-10-20

    ..., Marketing Specialist, or Kurt J. Kimmel, Regional Manager, California Marketing Field Office, Marketing...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 983 Pistachios Grown in California, Arizona, and New Mexico; Continuance Referendum AGENCY: Agricultural Marketing Service, USDA. ACTION...

  16. A new species of Rhadinella (Serpentes: Colubridae) from the Sierra Madre del Sur of Guerrero, Mexico.

    Science.gov (United States)

    Campillo, Gustavo; Dávila-Galavíz, Luis Fernando; Flores-Villela, Oscar; Campbell, Jonathan A

    2016-04-12

    We describe a new species of Rhadinella from the Sierra Madre del Sur of Guerrero, Mexico, a region where the genus was previously unknown. This diminutive species is a member of a group of snakes previously allocated in the Rhadinaea godmani group, and more recently transferred to the genus Rhadinella. These snakes may have conspicuous dark longitudinal striping on a pale brown to orange background or may have dark brown to blackish dorsal ground coloration, which mostly or completely obfuscates a pattern of longitudinal striping. The new species is mostly dark with barely discernible slightly paler or darker striping (depending on how striping is interpreted). The closest relative of the new species, on the basis of morphological similarities and biogeography, appears to be Rhadinella donaji which occurs to the east in the Sierra Madre del Sur of Oaxaca about 275 km from the type-locality of the new species.

  17. Potencial farmacológico de algas marinas de Baja California Sur, México

    OpenAIRE

    Muñoz Ochoa, Mauricio

    2010-01-01

    En este trabajo se estudiaron los extractos etanólicos de 62 especies de algas recolectadas a lo largo de la península de Baja California Sur, México, por su potencial como fuente de compuestos bioactivos. La actividad antibacteriana, antioxidante, citotóxica, anti-bioincrustante e inhibitoria de los mecanismo de resistencia bacteriana a los antibióticos fueron las actividades evaluadas en este trabajo de tesis. La primera parte de la tesis se centra en la identificación de las algas más prom...

  18. California sea lions (Zalophus californianus californianus) have lower chlorinated hydrocarbon contents in northern Baja California, Mexico, than in California, USA

    Energy Technology Data Exchange (ETDEWEB)

    Del Toro, Ligeia [Universidad Autonoma de Baja California (UABC), Facultad de Ciencias Marinas, Ensenada, Baja California (Mexico); Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico); Heckel, Gisela [Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico) and Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, B.C. Km 107 Carretera Tijuana-Ensenada, Ensenada, Baja California 22860 (Mexico)]. E-mail: gheckel@cicese.mx; Camacho-Ibar, Victor F. [Instituto de Investigaciones Oceanologicas, UABC, Apdo. Postal 453, Ensenada, Baja California 22860 (Mexico); Schramm, Yolanda [Universidad Autonoma de Baja California (UABC), Facultad de Ciencias Marinas, Ensenada, Baja California (Mexico); Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico)

    2006-07-15

    Chlorinated hydrocarbons (CHs) were determined in blubber samples of 18 California sea lions (Zalophus californianus californianus) that stranded dead along Todos Santos Bay, Ensenada, Baja California, Mexico, January 2000-November 2001. {sigma}DDTs were the dominant group (geometric mean 3.8 {mu}g/g lipid weight), followed by polychlorinated biphenyls ({sigma}PCBs, 2.96 {mu}g/g), chlordanes (0.12 {mu}g/g) and hexachlorocyclohexanes (0.06 {mu}g/g). The {sigma}DDTs/{sigma}PCBs ratio was 1.3. We found CH levels more than one order of magnitude lower than those reported for California sea lion samples collected along the California coast, USA, during the same period as our study. This sharp north-south gradient suggests that Z. californianus stranded in Ensenada (most of them males) would probably have foraged during the summer near rookeries 500-1000 km south of Ensenada and the rest of the year migrate northwards, foraging along the Baja California peninsula, including Ensenada, and probably farther north. - Results suggest that sea lion prey must also have lower hydrocarbons in Baja California than in California in the USA.

  19. Enfoques lingüísticos sobre la prehistoria del sur de California

    Directory of Open Access Journals (Sweden)

    Don Laylander

    1993-05-01

    Full Text Available El estudio de la evidencia sobre los idiomas indígenas yumanos, utoaztecanos y chumashanos del sur de California y de la parte norte de Baja California se plantea por el autor como una forma que puede ayudarnos a entender mejor el desarrollo prehistórico de la región. Para esto, se analizan en este documento diversos enfoques utilizados en los estudios lingüísticos de estas comunidades tempranas. El modelo genético de la descendencia lingüística sugiere que grupos de idiomas del periodo histórico tienen orígenes comunes, que son seguidos por una sucesión de separaciones que se pueden atribuir a diversos factores. La glotocronología ofrece estimaciones de los periodos de esas separaciones. La teoría de la migración evalúa la probabilidad relativa de que sean regiones particulares las patrias originales de las comunidades lingüísticas antes de que se dividieran. La difusión de lenguajes refleja las yuxtaposiciones geográficas e interacciones de comunidades de idiomas en el pasado. Por su parte la reconstrucción de la proto-cultura promete ayudar en la identificación de las patrias originales y de las sucesiones de innovaciones culturales

  20. Microfossils from Cerro Prieto geothermal wells, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Cotton, M.L.; Vonder Haar, S.

    1980-01-01

    To aid in a paleoenvironmental and age reconstruction of the Cerro Prieto reservoir system, 59 samples of well cuttings were analyzed for microfossils. The cuttings were obtained at depths from 351 to 3495 m in 14 geothermal wells in the Cerro Prieto field, Baja California, Mexico. We found foraminifera in 6 samples, ostracodes in 19 samples, and nannoplankton as coccoliths in 24 samples. Other groups, such as molluscs, insects, fish skeletal parts, and plant material were occasionally present. Detailed interpretations are not possible at this time because of poor preservation of samples. This is primarily due to causes: dissolution by geothermal fluids that reach 350{sup 0}C, and the extensive mixing of filled Cretaceous forms (reworked from the Colorado Plateau region) with Tertiary species during drilling. Further studies of ostracodes and foraminifera from colder portions of the wells are needed. The abundant and well-preserved ostracodes indicate marine to brackish water environments that correspond, in part, to lagoonal or estuarine facies. The presence of the mid-Tertiary (15-My-old) marine foraminifera, Cassigerinela chipolensis, in wells M-11 and M-38, 350 to 500 m deep, is perplexing. These are not laboratory contaminates and, as yet, have not been found in the drilling mud. If further studies confirm their presence at Cerro Prieto, established ideas about the opening of the Gulf of California and about Pacific Coast mid-Tertiary history will need to be rewritten.

  1. Microfossils from Cerro Prieto geothermal wells, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Cotton, M.L.; Haar, S.V.

    1982-08-10

    To aid in a paleonenvironmental and age reconstruction of the Cerro Prieto reservoir system, 59 samples of well cuttings were analyzed for microfossils. The cuttings were obtained at depths from 351 to 3495m in 14 geothermal wells in the Cerro Prieto field, Baja California, Mexico. Foraminifera was found in 6 samples, ostracodes in 19 samples and mannoplankton as coccoliths in 24 samples. Other groups, such as molluscus, insects, fish skeletal parts, and plant material were occasionally present. Detailed interpretations at this time cannot be made because of poor preservation of samples. This is primarily due to causes: dissolution by geothermal fluids that reach 350/sup 0/C, and the extensive mixing of filled Cretaceous forms (reworked from the Colorado Plateau region) with Tertiary species during drilling. Further studies of ostracodes and foraminifera from colder portions of the wells are needed. The abundant and well-preserved ostracodes indicate marine to backish water inviroments that correspond in part, to lagoonal or estuarine facies. The presence of the mid-Tertiary (15-m.y.-old) marine foraminifera, Cassigerinela chipolensis, in wells M-11 and M-38, 350 to 500m deep, is perplexing. These are not laboratory contaminates and, as yet have not been found in the drilling mud. If further studies confirm their presence at Cerro Prieto, established ideas about the opening of the Gulf of California and about Pacific Coast mid-Tertiary history will need to be rewritten.

  2. Management by results in Mexico, 2013-2014. Some effects in Baja California

    National Research Council Canada - National Science Library

    José María Ramos García

    2016-01-01

    .... This article analyzes the conceptual elements of the model and the manners in which this model has been instituted both conceptually and operationally in Brazil, Mexico, and the Mexican state of Baja California...

  3. Sustaining coupled social-ecological marine systems in Mexico's Gulf of California region

    Science.gov (United States)

    Leslie, H.

    2016-02-01

    Marine ecosystems provide many benefits to people, including food, protection from coastal storms, and places for recreation and spiritual renewal. These benefits are threatened by human impacts at multiple scales, including fisheries over-exploitation and global climatic change. More solutions-oriented knowledge of the connections between people and nature is urgently needed. I will discuss the approach my collaborators and I have developed to investigate the connections between people and marine ecosystems in the context of the small-scale fisheries of Mexico's Gulf of California. To illustrate the value of this coupled systems approach, I will present findings from two geographic scales. First, using a coupled bio-economic model based on several communities in the Mexican state of Baja California Sur (BCS), I will show how fishers' decisions are influenced by both climatic and institutional variation, and the consequences of these interactions for economic and ecological outcomes associated with fishing. Second, I will place these local-scale results in a broader context. Drawing on both natural and social science theory and data, I will show how environmental and institutional factors related to sustainability vary substantially throughout BCS. Fishing communities that exhibit greater potential for social-ecological sustainability in one dimension do not necessarily exhibit it in others. These results highlight the importance of integrative, coupled system analyses when implementing spatial planning and other ecosystem-based strategies and yield an understanding of the sustainability of coupled social-ecological systems that is quite distinct from that provided by either biophysical or social sciences alone.

  4. Physical profile data collected by the research vessel, Point Sur, near the coast of California, during February and June 1992 (NODC Accession 9400106)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical profile data were collected using CTD casts in the Coastal Waters of California from R/V POINT SUR. Data were collected from 09 February 1992 to 16 June...

  5. Heavy metals in geochemical sediment fractions of the border region between Baja California, Mexico, and California, USA; Metales pesados en fracciones geoquimicas de sedimentos de la region fronteriza de Baja California, Mexico, y California, EUA

    Energy Technology Data Exchange (ETDEWEB)

    Villaescusa-Celaya, Julio A; Gutierrez-Galindo, Efrain A; Flores-Munoz, Gilberto [Instituto de Investigaciones Oceanologicas, Universidad Autonoma de Baja California, Ensenada, B.C., (Mexico)

    1997-03-01

    The concentrations of the heavy metals Cu, Zn, Ni, Cr, Pb, Cd, Ag, Mn and Fe in the different geochemical sediment fractions are determined in this study, as a means of assessing the impact of residual wastewater on the coastal sediments of the region. During an oceanographic cruise in April 1992 (ECOBAC IV), 20 samples of surface sediments were collected from the coastal shelf of the border region between Baja California (Mexico) and California (USA), The sediment samples were subjected to a sequential extraction procedure designed to obtain the geochemical fractions defined as: exchangeable (F1), carbonates (F2), Fe and Mn oxyhydroxides (F3), organic matter/sulfides (F4) and residual or lithogenic (F5). The operational speciation of the metals indicates that the principal phases in the sediments that accumulate metal are the detrital or lithogenic matrix, the Fe and Mn oxyhydroxides and the organic Matter/sulfides, in this order. In general, the spatial distribution of the heavy metals in the reactive phase (defined as the sum of F1-F4) tended to increase in concentration in offshore sediments. The heavy metals in the reactive phase are apparently controlled by the concentration of reactive iron in the sediments, except for Pb, Cd and Ag, suggesting that the latter elements are controlled by other processes, such as particulate matter of biogenic origin. In contrast, the spatial distribution of heavy metals in the detrital phase behaved inversely, that is, the greatest concentrations of metals are found close to the coast off the wastewater treatment plant at Punta Bandera, Baja California. The average concentrations of total metals (sum of F1-F5) were 7.6, 40, 21, 68, 428, 11, 0.10 and 0.025 {mu}g{sup -}1 for Cu, Zn, Ni, Cr, Mn, Pb, Cd and Ag, respectively, and 2.3% for Fe. These concentrations are similar to those reported for uncontaminated reference sediments from southern California, indicating that a large amount of pollutants from the effluent of residual

  6. Desarrollo humano en el noroeste de México: un análisis comparativo de los estados de Sonora, Baja California y Baja California Sur, 1995-2005

    Directory of Open Access Journals (Sweden)

    Francisco José Zamudio Sánchez

    2009-01-01

    Full Text Available Este artículo aborda el desarrollo humano en Sonora, Baja California y Baja California Sur. Se estimaron los valores de cuatro índices: desarrollo humano con producto interno bruto, desarrollo humano con servicios, con género e inequidad; además de curvas de calidad estatal y municipal.Aunque los valores ubican a Baja California Sur en la mejor posición de los indicadores de desarrollo humano y después a Sonora; Baja California ocupa el mejor sitio en equidad en el país.

  7. en un área natural protegida en Baja California Sur

    Directory of Open Access Journals (Sweden)

    Elizabeth Olmos-Martínez

    2008-01-01

    Full Text Available Aquí se aborda el concepto de pobreza, enmarcado en el contexto de un área natural protegida (ANP, con la metodología propuesta por la Secretaría de Desarrollo Social (SEDESOL, cuya política pública maneja tres categorías para medirla: pobreza alimentaria, pobreza de capacidades y pobreza de patrimonio. El estudio de caso se efectuó en el ejido San Jorge (ESJ, ubicado dentro de la Reserva de la Biosfera Sierra La Laguna (REBISLA, en Baja California Sur. El análisis está basado en datos recolectados en entrevistas a los pobladores del lugar; se consideró el ingreso real diario per cápita, el cual indica si la persona es capaz de satisfacer las necesidades comprendidas en cada categoría, con un ingreso mínimo indispensable. Los resultados indican que la pobreza en la zona, de 2000 a 2004, no varió significativamente. Se concluyó que los habitantes del ESJ son pobres, según los propios parámetros de SEDESOL, y que su condición no ha mejorado, aunque viven en un ANP. Se analizan algunas alternativas que podrían ayudar a amortiguar este rezago.

  8. Petroleum geology of the Gulf of California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Guzman, A.E. (Petroleos Mexicanos (PEMEX), San Luis Potosi, Mexico)

    1990-05-01

    The Gulf of California basin proper is a very young (late Miocene) feature in northwestern Mexico, produced by the tectonic interaction of the Pacific and American plates. Sediments are mostly siliciclastic with thicknesses that may exceed 8,000 m (26,248 ft). Exploratory drilling started in 1979 and since then, ten offshore and seven onshore wells have been spudded. Foremost among the former the Extremeno 1 well tested from a thin deltaic sand 4,115 m deep (13,501 ft) a daily flow of 6.2 million ft{sup 3} of gas and 130 bbl of gas condensate through a 0.25 in. choke with a pressure of 280 kg/cm{sup 2} (3,981 psi). In the southern part of the basin, the offshore Huichol 1 well was also a gas and condensate producer, albeit noncommercial. Geologically, the basin's favorable generation and trapping conditions make up a very attractive scenario for a future petroleum producing province, once exploration priorities are considered timely.

  9. Climate change and the northern elephant seal (Mirounga angustirostris) population in Baja California, Mexico.

    Science.gov (United States)

    García-Aguilar, María C; Turrent, Cuauhtémoc; Elorriaga-Verplancken, Fernando R; Arias-Del-Razo, Alejandro; Schramm, Yolanda

    2018-01-01

    The Earth's climate is warming, especially in the mid- and high latitudes of the Northern Hemisphere. The northern elephant seal (Mirounga angustirostris) breeds and haul-outs on islands and the mainland of Baja California, Mexico, and California, U.S.A. At the beginning of the 21st century, numbers of elephant seals in California are increasing, but the status of Baja California populations is unknown, and some data suggest they may be decreasing. We hypothesize that the elephant seal population of Baja California is experiencing a decline because the animals are not migrating as far south due to warming sea and air temperatures. Here we assessed population trends of the Baja California population, and climate change in the region. The numbers of northern elephant seals in Baja California colonies have been decreasing since the 1990s, and both the surface waters off Baja California and the local air temperatures have warmed during the last three decades. We propose that declining population sizes may be attributable to decreased migration towards the southern portions of the range in response to the observed temperature increases. Further research is needed to confirm our hypothesis; however, if true, it would imply that elephant seal colonies of Baja California and California are not demographically isolated which would pose challenges to environmental and management policies between Mexico and the United States.

  10. Characterization of emissions sources in the California-Mexico Border Region during Cal-Mex 2010

    Science.gov (United States)

    Zavala, M. A.; Lei, W.; Li, G.; Bei, N.; Barrera, H.; Tejeda, D.; Molina, L. T.; Cal-Mex 2010 Emissions Team

    2010-12-01

    The California-Mexico border region provides an opportunity to evaluate the characteristics of the emission processes in rapidly expanding urban areas where intensive international trade and commerce activities occur. Intense anthropogenic activities, biomass burning, as well as biological and geological sources significantly contribute to high concentration levels of particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), nitrogen oxides (NOx), volatile organic compounds (VOCs), air toxics, and ozone observed in the California-US Baja California-Mexico border region. The continued efforts by Mexico and US for improving and updating the emissions inventories in the sister cities of San Diego-Tijuana and Calexico-Mexicali has helped to understand the emission processes in the border region. In addition, the recent Cal-Mex 2010 field campaign included a series of measurements aimed at characterizing the emissions from major sources in the California-Mexico border region. In this work we will present our analyzes of the data obtained during Cal-Mex 2010 for the characterization of the emission sources and their use for the evaluation of the recent emissions inventories for the Mexican cities of Tijuana and Mexicali. The developed emissions inventories will be implemented in concurrent air quality modeling efforts for understanding the physical and chemical transformations of air pollutants in the California-Mexico border region and their impacts.

  11. Análisis de los flujos turísticos en el corredor Los Cabos, Baja California Sur

    Directory of Open Access Journals (Sweden)

    Álvaro López López

    2001-09-01

    Full Text Available The Los Cabos corridor is one of the most dynamic tourism spaces in Mexico. In, around and towards this corridor, intense flows of tourists, migrants, merchandises and information takes place. Diverse in their territorial Impact as they are, most of them act as a link between the southernmost tip of the Baja peninsula and the state of California, in the United States. This is provoking a dissociation of this region of Mexico in its relation with the rest of the country that, to a certain extent, leads to a loss of national sovereignty.

  12. Mass media, espacio y tiempo en Todos Santos, Baja California Sur

    Directory of Open Access Journals (Sweden)

    Rossana Almada

    2001-01-01

    Full Text Available El artículo que aquí se sintetiza es un primer acercamiento, desde la perspectiva de autores entre los que destaca Manuel Castells, a un proyecto mayor que pretende analizar e interpretar el proceso de transformaciones que ha venido sufriendo el pueblo de Todos Santos, Baja California Sur BCS, debido a la llegada de dos contingentes de inmigrantes: el primero, rocedente de Estados Unidos y Canadá, llegó a comprar las casas del centro del pueblo; algunos con la intención de quedarse e instalar negocios, principalmente de venta de Bienes Raíces, otros, para pasar allí la temporada otoño invierno; y el segundo, traído del interior del país, principalmente de Acayucan Veracruz y de Ocotepec Guerrero como jornaleros agrícolas por una compañía Sinaloense. Esta inmigración ha introducido a Todos Santos dentro de lo que Castells denomina como sociedad red, es decir, dentro de procesos sociales organizados, cada vez más, en torno a redes que constituyen las nuevas formas de organización social. En resumen, el presente trabajo aborda los efectos de la globalización en la transformación de un pueblo sudcaliforniano, a través de la llegada de los inmigrantes arriba mencionados y del uso de los medios de comunicación vía satélite.

  13. Turismo y Sustentabilidad en Pequeñas Localidades Localidades Costeras de Baja California Sur (BCS

    Directory of Open Access Journals (Sweden)

    Reyna Ibañez Pérez

    2014-01-01

    Full Text Available El fomento del turismo se realiza en sitios que, aunque pequeños, cuentan con atractivos naturales y culturales, tal es el caso de las zonas costeras. Tan solo en México, se estima que existen más de 1,100 comunidades que dependen directamente de dicha actividad, esta te ndencia se refleja, de igual manera, en pequeñas localidades costeras de Baja California Sur (BCS. En este sentido, el objetivo de este trabajo fue realizar un an álisis exploratorio que permitió detectar a las comunidades costeras de BCS, donde el turismo genera un aporte importante a su economía local, además , se buscó identificar la problemática general que éstas enfrentan. Para realizar dicho estudio se revisó literatura, se organizó información estadística y se elaboró un análisis Fortalezas, Oportunidades, Debilidades y Amenazas (FODA. Los resultad os apuntan a que, en BCS, existen más de 35 localidades ru rales vinculadas con dicha actividad que comparten como problemática la escasa in fraestructura y la carencia de medidas de control de la afluencia turística. La principal recomendación es desarrollar líneas de investigación que permitan aportar elementos para medir la sustentabilidad turística a nivel local y, co n base en ello, diseñar medidas para la adecuada conducción de tan importante actividad.

  14. Stratigraphy of Pyroclastic Deposits of EL Aguajito Caldera, Baja California Sur, MÉXICO

    Science.gov (United States)

    Osorio Ocampo, L. S.; Macias, J. L.; García Sánchez, L.; Pola, A.; Saucedo, R.; Sánchez, J. M.; Avellán, D. R.; Cardona, S.; Reyes-Agustín, G.; Arce, J. L.

    2015-12-01

    El Aguajito caldera is located in the State of Baja California Sur, it comprises an area of 450 km2 and sits within the Santa Rosalía Basin which is controlled by NE-SW extensional structures and the NW-SE Cimarron Fault that transects the caldera structure. The oldest rocks are ~90 Ma granodiorites covered by an Oligocene-Miocene volcano-sedimentary sequence, the Miocene Santa Lucia Formation and La Esperanza basalt. Pliocene volcanism is represented by La Reforma caldera, El Aguajito caldera, and the Tres Vírgenes Volcanic complex. This study focuses on the cartography and stratigraphy of area in order to understand the evolution of the volcanic system. The stratigraphy from base to top consists of a series of shallow marine sediments (fossiliferous sandstones) covered by a thick sequence of ignimbrites and pyroclastic flows interbedded with volcaniclastic deposits (Gloria and El Infierno Formations). On top of these deposits is El Aguajito caldera, it consists of a 2 m thick pumice fallout followed by an ignimbrite with three transitional lithofacies: a ≤30-m thick light-pink pyroclastic flow enriched in pumice at the base that gradually becomes enrich in lithics towards the top with the occurrence of degasing pipes. On top rests a 15 m-thick light-purple ignimbrite slightly welded with fiammes and a sequence of pumiceous pyroclastic flows and fallouts. These deposits have been associate to the caldera formation with a collapse diameter of ~8 km marked by rhyolitic domes exposed along a ring collapse crowned the sequence as well as NW-SE aligned rhyolitic domes parallel to the seashore. This cartography allowed to present a preliminary new geological map with four stratigraphic units recognized so far, that were emplaced under subaerial conditions beginning with a Plinian column followed by the emplacement of El Aguajito ignimbrite with its subsequent caldera collapse and finally the extrusion of resurgent domes.

  15. 77 FR 36119 - Pistachios Grown in California, Arizona, and New Mexico; Order Amending Marketing Order No. 983

    Science.gov (United States)

    2012-06-18

    ... Agricultural Marketing Service 7 CFR Part 983 Pistachios Grown in California, Arizona, and New Mexico; Order Amending Marketing Order No. 983 AGENCY: Agricultural Marketing Service, USDA. ACTION: Final rule. SUMMARY... ``Marketing Agreement Regulating the Handling of Pistachios Grown in California, Arizona, and New Mexico...

  16. Feeding habits of the Panama Brief Squid (Lolliguncula panamensis) in the Gulf of California, Mexico

    OpenAIRE

    Arizmendi-Rodríguez, Dana I.; Cruz Escalona, Víctor Hugo; Quiñonez Velazquez, Casimiro; Salinas-Zavala, César A.

    2011-01-01

    The feeding habits of the Panama brief squid, Lolliguncula panamensis (Berry, 1911), it inhabits off Peru until Gulf of California, was determined by examining the stomach contents of 657. Panama brief squid were collected from the incidental catch of shrimp trawling fishery during 2003-2006 and 2008, along the Gulf of California, Mexico. Most of the stomachs were empty and those that contained food presented highly digested prey items. Eight taxa were identified in the stomach contents and t...

  17. Early Miocene shortening in the lower Comondú Group in Baja California Sur (México)

    Science.gov (United States)

    Bonini, Marco; Cerca, Mariano; Moratti, Giovanna; López-Martínez, Margarita; Corti, Giacomo; Gracia-Marroquín, Diego

    2017-11-01

    The Late Oligocene-Early Miocene volcaniclastic deposits of Baja California Sur form most of the exposed western margin of the Gulf of California rift. In some places these deposits, collectively referred to as Comondú Group, show complex deformation patterns given by the coexistence of tectonic and gravitational features. The area north of La Paz is characterized by the occurrence of several slump bodies, which are displaced by normal faults connected with the rift opening. In some places we have identified 100's m scale thrust-related folds and reverse faults that we have interpreted as shortening features. The latter displace the slump layers and are offset by the normal faults. If confirmed, this would represent the first report of a shortening event in the Early Miocene volcaniclastic deposits of Baja California Sur. The observed shortening has modest magnitude (ca 3-5% bulk shortening), and has been detected in a sector extending over 100 km north from La Paz. New 40Ar-39*Ar ages, integrated with existing radiometric age datasets, constrain the timing of this shortening episode. The rocks affected by shortening have ages between 24 and 21 Ma, and are capped by undeformed volcanic rocks with ages spanning between 19.4 and 17.2 Ma. These relationships define an intra-Early Miocene unconformity, which we interpret to be related to the shortening deformation. The available timing constraints allow us to infer that a main ENE-to-ESE-trending shortening was short-lived, possibly ca. 19.4-21 Ma. The account of this shortening event may shed some light on the complex subduction and microplate processes that preceded the continental rifting of the Gulf of California.

  18. 76 FR 34181 - Pistachios Grown in California, Arizona, and New Mexico; Proposed Amendments to Marketing Order

    Science.gov (United States)

    2011-06-13

    ... Agricultural Marketing Service 7 CFR Part 983 Pistachios Grown in California, Arizona, and New Mexico; Proposed Amendments to Marketing Order AGENCY: Agricultural Marketing Service, USDA. ACTION: Proposed rule. SUMMARY: Four amendments to Marketing Agreement and Order No. 983, which regulates the handling of pistachios...

  19. 76 FR 60361 - Pistachios Grown in California, Arizona, and New Mexico; Decreased Assessment Rate

    Science.gov (United States)

    2011-09-29

    ... Internet at the address provided above. FOR FURTHER INFORMATION CONTACT: Andrea Ricci, Marketing Specialist... Agricultural Marketing Service 7 CFR Part 983 Pistachios Grown in California, Arizona, and New Mexico; Decreased Assessment Rate AGENCY: Agricultural Marketing Service, USDA. ACTION: Interim rule with request...

  20. Health Care among the Kumiai Indians of Baja California, Mexico: Structural and Social Barriers

    Science.gov (United States)

    Fleuriet, K. Jill

    2009-01-01

    In this article, the author documents the illness and health care problems facing indigenous communities in Baja California, Mexico, by using ethnographic data from research she conducted from 1999 to 2001 with rural, indigenous Kumiai and with their primary health care providers in urban Ensenada. The author contends that barriers to care are…

  1. Update: mercury poisoning associated with beauty cream--Arizona, California, New Mexico, and Texas, 1996.

    Science.gov (United States)

    1996-07-26

    During September 1995-May 1996, the Texas Department of Health (TDH), the New Mexico Department of Health (NMDH), and the San Diego County (California) Health Department investigated three cases of mercury poisoning associated with the use of a mercury-containing beauty cream produced in Mexico. The ongoing investigation has found this product in shops and flea markets in the United States located near the U.S.-Mexico border, and a U.S. distributor has been identified in Los Angeles. The cream, marketed as "Crema de Belleza--Manning" for skin cleansing and prevention of acne, listed "calomel" (mercurous chloride [Hg2Cl2]) as an ingredient and contained 6% to 10% mercury by weight. This report presents findings of a continuing investigation by these health departments, the Arizona Dept of Health Services (ADHS), California State Department of Health Services (CSDHS), the Food and Drug Administration (FDA), and CDC.

  2. Geographical mobility among retired US migrants living in the Northwestern region of Mexico bordering California, US

    Directory of Open Access Journals (Sweden)

    Lardiés-Bosque Raúl

    2016-06-01

    Full Text Available Mexico has become a regular destination for retirees coming from the USA. To date certain aspects of this group of migrants have been analysed, but little is known about those who have changed their place of residence to the Mexico- US border. In this article, the geographical mobility among retired US migrants living in the coastal area of northern Baja California, Mexico, is analysed. Firstly, reasons for retirees moving from the USA to this area are considered, and secondly, the contacts and relationships maintained with the country of origin, measured by the mobility which takes place between both countries; attention will be given to the reasons for these frequent trips, their periodicity, the means of transport used and the impacts. The main source of analysis will be 29 in-depth interviews conducted in 2009 with pensioners living in coastal municipalities of this northern area of Mexico.

  3. [Echinoderms (Echinodermata) from the Gulf of California, Mexico].

    Science.gov (United States)

    Solís-Marín, Francisco A; Laguarda-Figueras, Alfredo; Durán-González, Alicia; Ahearn, Cynthia Gust; Torres Vega, Juan

    2005-12-01

    A systematic list of the echinoderms of the Gulf of California, based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. A total of 193 echinoderm species is recorded, distributed in 108 genera, 51 families and 19 orders. 12 new records for the Gulf of California are presented: Asteroidea (four), Ophiuroidea (three) and Holothuroidea (five).

  4. LAS MUJERES EN LA MIGRACIÓN INTERNA Y EL EMPLEO INFORMAL EN BAJA CALIFORNIA SUR, MÉXICO

    Directory of Open Access Journals (Sweden)

    ALBA E. GÁMEZ

    2010-01-01

    Full Text Available Este artículo analiza las características del fenómeno migratorio en Baja California Sur, en la costa norte del Pacífico mexicano, donde el turismo y la agricultura de exportación son dos sectores atractores de población. Esto ha estimulado una tasa de crecimiento demográfico promedio de 10% en la última década en regiones como Los Cabos, de las que se alimentan los sectores formal e informal. El propósito de este artículo es contribuir a la comprensión de la participación de las mujeres migrantes en el mercado laboral informal.

  5. Crustal thickness estimates for Baja California, Sonora, and Sinaloa, Mexico, using disperse surface waves

    Science.gov (United States)

    López-Pineda, Leobardo; Rebollar, Cecilio J.; Quintanar, Luis

    2007-04-01

    Dispersed surface waves of regional events recorded at Network of Autonomously Recording Seismographs (NARS)-Baja and Red Sísmica de Banda Ancha (RESBAN) networks located over the Baja California Peninsula, Sonora, and Sinaloa, Mexico, were used to estimate shear wave elastic models and crustal thickness. We analyzed fundamental modes of surface waves with period between 10 and 40 s. Multiple filter analysis and the inversion method described by Herrmann and Ammon (2003) was used. Crustal thickness estimates for the Peninsular Ranges of Northern Baja California agree with those obtained by previous studies in the Peninsular Ranges of Northern Baja California. We analyzed dispersion of surface waves with northwest-southeast travel paths along the east and west sides of the Baja California Peninsula as well as a northwest-southeast travel path along the western sides of the Mexican states of Sonora and Sinaloa. It was found that the crustal structure east of the Baja California Peninsula is similar to the structure of Sonora and Sinaloa. The correlation between those two structures suggests dextral offset of the order of 275 ± 25 km if we consider Baja California Peninsula as a rigid body moving toward the northwest relative to the North America plate. This displacement between the structures is in agreement with the displacement determined by the dating of Miocene deposits located in San Felipe on the Baja California Peninsula (Pacific plate), and Isle Tiburon located west of Sonora (North America plate).

  6. Desarrollo, identidad cultural y turismo en los oasis de Baja California Sur, México

    National Research Council Canada - National Science Library

    Alexandra Sauvage; Alba E. Gámez

    2013-01-01

    .... These rural communities are located in one of the largest oasis in the arid Baja California peninsula and face the risks of cultural commodification from the growth of the real estate and tourism sectors...

  7. Ventaja competitiva sostenible en pequenas y medianas empresas hoteleras del sur de Mexico

    National Research Council Canada - National Science Library

    de la Paz Hernandez Giron, Jose; Dominguez Hernandez, Maria Luisa; de Ita Castillo, Diana

    2008-01-01

    ...). Se encuesto a 49 administradores de hoteles en los estados de Oaxaca y Puebla (Mexico). En los resultados, la capacidad de mercadotecnia se relaciona fuertemente con la innovacion organizacional y con la...

  8. Revisión estratigráfica de Punta Coyote (Baja California Sur, México e implicaciones para el volcanismo de la Sierra Madre Occidental y el arco Comondú

    Directory of Open Access Journals (Sweden)

    Puy-Alquiza, M. J.

    2010-12-01

    Full Text Available We present new stratigraphic evidence for a migration of the Upper Volcanic Supergroup that formed the Sierra Madre Occidental (SMO volcanic arc in northwestern Mexico during the Oligocene-Miocene. Particularly we discuss the transition from the frontal arc to the Comondú volcanic arc in Punta Coyote, Baja California Peninsula. This information complements the knowledge of the stratigraphic evolution of the Oligocene-Miocene volcanic arc in Baja California and its correlation with the Upper Volcanic Supergroup of the Sierra Madre Occidental in northwestern Mexico. We present new stratigraphic and sedimentologic data of the volcanosedimentary succession of the lower unit of the Comondú group near of La Paz, Baja California Sur, Mexico, in Punta Coyote. Facies analysis and new 40Ar /39Ar dating allowed to interpret the sedimentary environment and evolution of volcanic pulses in the lower unit of the Comondú group in Punta Coyote. The study area was part of the forearc basin westward to the SMO volcanic arc during the Oligocene to early Miocene. The sedimentary environment of the lower unit of the Comondú group was initially a braided river system that prograded to an alluvial fan environment and three tuffs units: Los Azabaches tuff (30.6±0.4 Ma, La Capilla and El Oro tuffs (22.0±0.4 Ma. The succession studied provides new stratigraphic information related to the evolution of the Oligocene-Miocene volcanic arc in the Baja California Peninsula and its correlation with the Upper Volcanic Supergroup of the SMO in northwestern Mexico.

    Se presentan nuevos datos sobre la estratigrafía y sedimentología de la sucesión volcanosedimentaria de la Unidad Inferior del Grupo Comondú (UIGC al noreste de la ciudad de La Paz, en Punta Coyote, Baja California Sur, México. El análisis de facies, así como las nuevas dataciones 40Ar /39Ar permitieron interpretar la evolución del ambiente sedimentario y

  9. Crecimiento y mortalidad de la madreperla Pinctada mazatlanica en poblaciones naturales del litoral oriental de Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Humberto Wright-López

    2009-06-01

    Full Text Available La madreperla Pinctada mazatlanica esta en veda desde 1939 y considerada en peligro de extinción, cambiando su categoría a protección especial en 1994. El presente estudio estima su crecimiento y mortalidad en bancos naturales en el periodo 1992-93 y 1997-99. Se registró el alto de la concha de ostras en poblaciones desde el paralelo 28º a 23º LN del litoral oriental de Baja California Sur, abarcando 38 estaciones, 2 bahías y 6 islas. La longitud máxima estimada fue 187.22mm (179.83-195.81mm, P > 0.95. Las frecuencias de longitud se ordenaron en un "año virtual". Los parámetros de crecimiento de von Bertalanffy estimados con el programa ELEFAN I fueron: o = 193.31mm, k=0.54año-1, t0= -0.1805 años, C=0.49 y WP=0.75; el índice de desempeño del crecimiento fue’=4.305. La mortalidad total fue de Z=2.03 año-1 por longitud convertida a curva de captura. La regresión peso total y la altura tuvo la expresión W(i=0.0005418 * L(i2.7301. Los parámetros de crecimiento fueron similares a los de Pinctada margaritifera de bancos de mar abierto y diferentes a aquellos de ostras perleras en repoblamiento en bahía de La Paz. La mortalidad mostró valores parecidos a los estimados para Pinctada radiata del Mar Rojo.Growth and mortality of the mother-of-pearl Pinctada mazatlanica in natural populations of the east coast of Baja California Sur, Mexico. The Mexican Pacific mother-of-pearl Pinctada mazatlanica was placed in forbidden fisheries status for the Mexican Federal Government and considered in extinction danger since 1939. This decree was modified in 1994 to allow the capture of spat for research or marine culture. We estimated the growth and mortality of mother-of-pearl from the eastern littoral of South Baja California wild stock in the periods 1992-93 and 1997-99. We used 38 sample stations at 2 bays and 6 insular complexes. The maximum length was 187.22 mm (179.83-195.81 mm, P > 0.95. Seasonal von Bertalanffy growth (ELEFAN I routine

  10. Recent distribution and status of nesting bald eagles in Baja California, Mexico

    Science.gov (United States)

    Henny, C.J.; Conant, B.; Anderson, D.W.

    1993-01-01

    We studied Bald Eagles(Haliaeetus leucocephalus) nesting in Baja California, Mexico, and vicinity from 1983-1993. The range of nesting Bald Eagles in Baja California has been reduced from a scattering of pairs along both the Pacific and Gulf sides to a remnant population in Magdalena Bay where no more than three pairs were found annually. Low numbers and a restricted distribution make this disjunct population especially vulnerable to human disturbance. Additional protection of present nesting localities and a reintroduction program on remote islands in the Gulf of California where eagles historically nested, are proposed. Limited data on nesting success indicate that the Magdalena Bay population is reproducing successfully with young probably dispersing north following fledging. The Bald Eagles found wintering along the Colorado River Delta in January apparently nest farther north in the United States or Canada.

  11. The economic value chain of wine in Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    Salvador González Andrade

    2015-07-01

    Full Text Available Recent economic policy debates have centered on increasing and quantifying the value chain, and the objective of this research is to characterize the value chain of vitiviniculture in Baja California according to organizational subsystems, including management, marketing, quality, productivity and environment. This study presents a comparative analysis between the capabilities of the vitiviniculture industry and sectors within which it participates. The analysis shows that the primary issues are related to sectors that have weak productive infrastructure, marketing problems, product shortages and few local suppliers, and additional problems include insufficient funding, water shortages and high taxes. Moreover, investments in human capital are required to train human resources.

  12. Isla Guadalupe, Mexico (GUAX, SCIGN/PBO) a Relative Constraint for California Borderland and Northern Gulf of California Motions.

    Science.gov (United States)

    Gonzalez-Garcia, J. J.

    2004-12-01

    Using ITRF2000 as a common reference frame link, I analyzed survey mode and permanent GPS published results, together with SOPAC public data and results (http://sopac.ucsd.edu), in order to evaluate relative present day crustal deformation in California and northern Mexico. The crustal velocity field of Mexico (Marquez-Azua and DeMets, 2003) obtained from continuous GPS measurements conducted by Instituto Nacional de Geografia e Informatica (INEGI) for 1993-2001, was partially used. The preferred model for an instantaneous rigid motion between North-America and Pacific plates (NAPA), is obtained using results of Isla Guadalupe GPS surveys (1991-2002) giving a new constraint for Pacific plate (PA) motion (Gonzalez-Garcia et al., 2003). It produces an apparent reduction of 1 mm/yr in the absolute motion in the border zone between PA and North-America (NA) plates in this region, as compared with other GPS models (v.g. Prawirodirdjo and Bock, 2004); and it is 3 mm/yr higher than NNRNUVEL-1A. In the PA reference frame, westernmost islands from San Francisco (FARB), Los Angeles (MIG1), and Ensenada (GUAX); give current residuals of 1.8, 1.7 and 0.9 mm/yr and azimuths that are consistent with local tectonic setting, respectively. In the NA reference frame, besides the confirmation of 2 mm/yr E-W extension for the southern Basin and Range province in northern Mexico; a present day deformation rate of 40.5 mm/yr between San Felipe, Baja California (SFBC) and Hermosillo, Sonora, is obtained. This rate agrees with a 6.3 to 6.7 Ma for the "initiation of a full sea-floor spreading" in the northern Gulf of California. SFBC has a 7 mm/yr motion in the PA reference frame, giving then, a full NAPA theoretical absolute motion of 47.5 mm/yr. For Puerto Penasco, Sonora (PENA) there is a NAPA motion of 46.2 mm/yr and a residual of 1.2 mm/yr in the NA reference frame, this site is located only 75 km to the northeast from the Wagner basin center. For southern Isla Guadalupe (GUAX) there

  13. Análisis de la oferta de ostión japonés en el estado de Baja California Sur (México

    Directory of Open Access Journals (Sweden)

    Mauro Alejandro Monroy Ceseña

    2016-02-01

    Full Text Available Esta investigación analiza el comportamiento de la oferta local de ostión japonés en el estado de Baja California Sur y la oferta nacional en México. El estudio es de tipo descriptivo y el diseño, no experimental. Los resultados muestran una tendencia fructífera para los tomadores de decisión en el sector, dentro de un marco estratégico.

  14. Morphological variability of intertidal Eisenia arborea (Laminariales, Ochrophyta) at Punta Eugenia, Baja California Sur

    OpenAIRE

    Parada, Gloria M; Riosmena-Rodríguez, Rafael; Enrique A Martínez; Hernández Carmona, Gustavo

    2012-01-01

    Water motion is one of the main drivers in morphological variability in species within de order Laminariales, and most of our current knowledge is based on subtidal populations. Eisenia arborea is a dominant kelp species in the North Pacific, widely distributed along the Baja California Peninsula from mid intertidal down to subtidal areas. This species presents great variability in the intertidal zone but it has not been yet evaluated such variability according to wave exposure. The present w...

  15. Land use change in the Baja California Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Gerardo Bocco

    2009-10-01

    Full Text Available This work analyzes the land use change in the Baja California Peninsula, at the level of vegetation types. The time period analyzed was 1978 (Serie I de INEGI to 2000 (Inventario Nacional Forestal at 1:250 000 scale. The spatial analyses were carried out in a GIS environment to identify the changes in the period. A transition matrix was elaborated and the changes detected were grouped in three major processes: scrubland depletion (deforestation of woody vegetation, recovery of natural vegetation cover, and urban growth. In the time period analyzed (22 years 7.7 % of the territory underwent land use changes. The deforestation and urbanization processes were more dynamic in the northern part of the peninsula, while recovery was more relevant in the south zone. The deforestation of scrubland for agriculture activities is the main process in the peninsula. The urbanization, in absolute terms, is the least important in the time period analyzed; however, the surface occupied for human settlements increased in almost 270 %.

  16. Review of Neopalpa Povolný, 1998 with description of a new species from California and Baja California, Mexico (Lepidoptera, Gelechiidae

    Directory of Open Access Journals (Sweden)

    Vazrick Nazari

    2017-01-01

    Full Text Available The monotypic genus Neopalpa was described in 1998 by Czech entomologist Dalibor Povolný based on two male specimens from Santa Catalina Island, California, which he named N. neonata. The female of this species was discovered recently based on a DNA barcode match and is described. In addition, a new species with marked differences in morphology and DNA barcodes from southern California and Baja California Mexico is described as Neopalpa donaldtrumpi sp. n. Adults and genitalia of both species are illustrated, new diagnosis for the genus Neopalpa is provided, and its position within Gelechiidae is briefly discussed.

  17. Review ofNeopalpaPovolný, 1998 with description of a new species from California and Baja California, Mexico (Lepidoptera, Gelechiidae).

    Science.gov (United States)

    Nazari, Vazrick

    2017-01-01

    The monotypic genus Neopalpa was described in 1998 by Czech entomologist Dalibor Povolný based on two male specimens from Santa Catalina Island, California, which he named Neopalpa neonata . The female of this species was discovered recently based on a DNA barcode match and is described. In addition, a new species with marked differences in morphology and DNA barcodes from southern California and Baja California Mexico is described as Neopalpa donaldtrumpi sp. n. Adults and genitalia of both species are illustrated, new diagnosis for the genus Neopalpa is provided, and its position within Gelechiidae is briefly discussed.

  18. Overview Of Cal-Mex 2010: US-Mexico Collaborative Project On Air Quality And Climate Change In The California-Mexico Border Region

    Science.gov (United States)

    Molina, L. T.; Cal-Mex Science Team

    2010-12-01

    The composition of the atmosphere over the US-Mexico border region is affected by cross-border transport of emissions in both directions. Air quality issues in the California-Mexico (Cal-Mex) border are associated with air masses originating in the portion of the border region adjacent to California, which includes two of the sister city pairs (Tijuana-San Diego and Mexicali-Calexico) that have the most severe air pollution problems, posing a serious health threat to their inhabitants as well as affecting ecosystem viability and regional climate for large downwind distances. During May-June 2010, an intensive field study was undertaken by US-Mexico collaborative teams to characterize the major sources of primary and secondary particulate matter and precursor gases in the California-Mexico (Cal-Mex) border region, their transport and transformation, and the impact of these emissions on regional air quality and climate. The ground-based measurements included a central fixed site located in Tijuana that housed state-of-the-science instruments to measure gases, aerosols, radiation and meteorological parameters; a mobile eddy covariance laboratory that measured surface-atmosphere exchange fluxes of carbon dioxide, nitrogen oxides, and particle number; several mobile units for criteria pollutants and meteorological parameters; and measurements of fine particles and trace gases at the border crossing areas. Preliminary results from the field study will be presented. Cal-Mex Science Team includes: Molina Center for Energy and the Environment, Texas A & M University, Scripps Institution of Oceanography/University of California at San Diego, Virginia Tech, San Diego State University, National University of Mexico, National Institute of Ecology/Mexican Ministry of the Environment, University of the State of Morelos, LT Consulting Group, University of Baja California (Mexicali, Tijuana, Ensenada, Valle de Las Palmas campuses), Secretary of the Environment of Baja California

  19. Morfometria en la cuenca hidrologica de San Jose del Cabo, Baja California Sur, Mexico

    National Research Council Canada - National Science Library

    Martinez, Genaro; Diaz, Jose J

    2011-01-01

    .... Analisis de imagen Landsat ETM, fotografias aereas y modelo digital de elevacion fueron usados para cartografiar la geomorfologia, geologia y desarrollar un analisis morfometrico en la margen occidental de la cuenca...

  20. Antimony in the Contaminated Site of El Triunfo, Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Marmolejo-Rodríguez A. J.

    2013-04-01

    Full Text Available Antimony has properties similar to arsenic with some of its compounds toxic to humans. Therefore it is necessary to control the wastes accumulated by anthropogenic activities, such as mining, where it is in tailings to be released to the environment. According to the Environment Protection Agency, the maximum value in sediments is 11.2 mg Sb kg–1 and the Earth’s crust average is 0.2 mg Sb kg–1. In this semiarid area, the drainage basin El Carrizal is impacted with wastes of an abandoned gold mine at the Mining District El Triunfo (MD – ET which have tailings with 17,600 mg kg–1 of antimony. In the main dry river (arroyo, the Sb content is between 0.6 and 122 mg kg–1. This element is transported from the source throughout the fluvial basin to discharge into the Pacific Ocean. In the arroyo mouth we collected one sedimentary core and the sediment from dunes (28.6 – 45.7 and 6.43 – 7.74 mg Sb kg–1. This research concluded the antimony is enriched in this semiarid system, with Normalized Enrichment Factors severely enriched mainly in arroyo sediments close to the MD-ET

  1. Results and evaluation of the first study of organochlorine contaminants (PCDDs, PCDFs, PCBs and DDTs), heavy metals and metalloids in birds from Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, Begona [Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain)]. E-mail: bjimenez@iqog.csic.es; Rodriguez-Estrella, Ricardo [Centro de Investigaciones Biologicas del Noroeste, Mar Bermejo 195, Apdo. Postal 128, La Paz, Baja California Sur (Mexico); Merino, Ruben [Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Gomez, Gema [Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Rivera, Laura [Centro de Investigaciones Biologicas del Noroeste, Mar Bermejo 195, Apdo. Postal 128, La Paz, Baja California Sur (Mexico); Jose Gonzalez, Maria [Department of Instrumental Analysis and Environmental Chemistry, Institute of Organic Chemistry, CSIC, Juan de la Cierva 3, 28006 Madrid (Spain); Abad, Esteban [Department of Ecotechnologies, Research and Development Center, CSIC, Jordi Girona, 18-26, 08034 Barcelona (Spain); Rivera, Josep [Department of Ecotechnologies, Research and Development Center, CSIC, Jordi Girona, 18-26, 08034 Barcelona (Spain)

    2005-01-01

    Organochlorine compounds (OCs) including polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p-p'-DDE), heavy metals (Pb, Cd, Zn, Cu), and arsenic were measured in house sparrows (Passer domesticus) and common ground doves (Columbina passerina) from Baja California Sur, Mexico. Concentrations of PCDD/Fs were low, with 21 pg/g for house sparrows, and 7.7 pg/g for common ground doves. Non-ortho-PCB concentrations in house sparrow and common ground doves were 58 and 254 pg/g, respectively, and are within the highest concentrations reported in species that are in the low levels of food webs. The major differences in organochlorine levels between species were found for ortho-PCBs and DDTs. ortho-PCB levels were higher in the seedeater species, whereas DDT levels were higher in the omnivorous species. Heavy metal levels were far below those associated with negative effects. - Capsule: The first data on contaminants in birds from Baja California is given.

  2. Superficial simplicity of the 2010 El Mayorg-Cucapah earthquake of Baja California in Mexico

    Science.gov (United States)

    Wei, S.; Fielding, E.; Leprince, S.; Sladen, A.; Avouac, J.-P.; Helmberger, D.; Hauksson, E.; Chu, R.; Simons, M.; Hudnut, K.; Herring, T.; Briggs, R.

    2011-01-01

    The geometry of faults is usually thought to be more complicated at the surface than at depth and to control the initiation, propagation and arrest of seismic ruptures1-6. The fault system that runs from southern California into Mexico is a simple strike-slip boundary: the west side of California and Mexico moves northwards with respect to the east. However, the Mw 7.2 2010 El Mayorg-Cucapah earthquake on this fault system produced a pattern of seismic waves that indicates a far more complex source than slip on a planar strike-slip fault. Here we use geodetic, remote-sensing and seismological data to reconstruct the fault geometry and history of slip during this earthquake. We find that the earthquake produced a straight 120-km-long fault trace that cut through the Cucapah mountain range and across the Colorado River delta. However, at depth, the fault is made up of two different segments connected by a small extensional fault. Both segments strike N130 ??E, but dip in opposite directions. The earthquake was initiated on the connecting extensional fault and 15s later ruptured the two main segments with dominantly strike-slip motion. We show that complexities in the fault geometry at depth explain well the complex pattern of radiated seismic waves. We conclude that the location and detailed characteristics of the earthquake could not have been anticipated on the basis of observations of surface geology alone. ?? 2011 Macmillan Publishers Limited. All rights reserved.

  3. Clinical Outcomes and Hospitalizations among Children Perinatally Infected with HIV-1 in Baja California, Mexico.

    Science.gov (United States)

    Viani, Rolando M; Araneta, Maria Rosario G; Lopez, Graciano; Chacón-Cruz, Enrique; Spector, Stephen A

    2011-01-01

    This study characterizes temporal trends in HIV disease progression among perinatally infected children at a clinic in Baja California, Mexico. A total of 73 children were followed, 52% were categorized under US Centers for Disease Control and Prevention (CDC) classification group C with a mean age of 2.3 years (SD ± 3.16) at HIV diagnosis. For the years 1998 to 2001, 2002 to 2003, 2004 to 2005, and 2006 to 2007, highly active antiretroviral therapy (HAART) use increased to 60%, 75%, 83%, and 94% (P mortality was 31% (23 of 73), with pneumonia being the most common cause of death (43% of all deaths) followed by tuberculosis (22%). Mortality rates declined from 30.4% to 25%, 8.9%, and 9.3% (p = 0.035) for the years 1998 to 2001, 2002 to 2003, 2004 to 2005, and 2006 to 2007, respectively. Kaplan-Meier survival analysis showed that median survival was 11.2 years; 1-, 2-, and 5-year survival was 87%, 83%, and 67%, respectively. These findings document a high but improving trend in morbidity and mortality of children perinatally infected with HIV in Tijuana, Baja California, Mexico.

  4. Maternal perceptions of early childhood ideal body weight differ among Mexican-origin mothers residing in Mexico compared to California.

    Science.gov (United States)

    Guendelman, Sylvia; Fernald, Lia C H; Neufeld, Lynnette M; Fuentes-Afflick, Elena

    2010-02-01

    To assess maternal perceptions of children's current and ideal body sizes, and the meaning of and factors contributing to overweight in infancy and early childhood among Mexican-origin mothers living in Mexico and in California. A quali-quantitative study combining focus groups and a self-administered questionnaire. A purposive sample of 84 low-income, Mexican-origin mothers of 4- to 6-year-old children recruited between March 2006 and January 2008 from rural and urban communities in Mexico and California. Bivariate, multivariate, and qualitative analyses of maternal perceptions of children's actual and ideal body size supplemented by qualitative analyses of meaning of and factors contributing to childhood overweight/obesity. Ideal child body size was considerably lower among Mexican-origin mothers living in California (3.86+/-0.56) than it was among mothers living in Mexico (4.32+/-0.83), and this difference was significant (P=0.001) after adjusting for sociodemographic covariates. Among mothers of overweight children, 82% of mothers in California were dissatisfied with their child's weight compared with 29% of mothers in Mexico (P=0.003). Focus-group results suggest that these differences in the perception of children's ideal body size can be attributable to differences in body size norms among mothers and awareness of the negative effects of obesity that occur after migration to California. Maternal perceptions of early childhood overweight appear to differ among Mexican-origin women living in Mexico and California. Recognition of the negative health consequences of obesity and identification of barriers to achieving weight control are important first steps toward childhood obesity prevention. Interventions directed at Mexican-origin mothers should focus on culturally acceptable ways of transmitting weight-control information. Copyright 2010 American Dietetic Association. Published by Elsevier Inc. All rights reserved.

  5. 76 FR 57001 - Pistachios Grown in California, Arizona, and New Mexico; Proposed Amendment of Marketing Order No...

    Science.gov (United States)

    2011-09-15

    ...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 983 Pistachios Grown in California, Arizona, and New Mexico; Proposed Amendment of Marketing Order No. 983 and Referendum Order AGENCY: Agricultural Marketing Service, USDA. ACTION: Proposed rule and referendum order. SUMMARY: This rule proposes...

  6. A new species of palaemonid shrimp, Chacella tricornuta spec. nov (Crustacea: Decapoda: Palaemonidae) from the southeastern Gulf of California, Mexico

    NARCIS (Netherlands)

    Hendrickx, M.E.

    1990-01-01

    A new species of the palaemonid shrimp genus Chacella Bruce is described from the Gulf of California, Mexico, in the eastern Pacific, and represents the second known species of this genus. The type-species, Chacella kerstitchi (Wicksten, 1983), was described from a single female captured off the

  7. Molecular epidemiology of Mycobacterium tuberculosis in Baja California, Mexico: A result of human migration?

    Science.gov (United States)

    Flores-López, Carlos A; Zenteno-Cuevas, Roberto; Laniado-Laborín, Rafael; Reynaud, Yann; García-Ortiz, Rosa Alejandra; González-Y-Merchand, Jorge A; Rivera, Sandra; Vázquez-Chacón, Carlos A; Vaughan, Gilberto; Martínez-Guarneros, José Armando; Victoria-Cota, Nelva Lorena; Cruz-Rivera, Mayra; Rastogi, Nalin; Muñiz-Salazar, Raquel

    2017-11-01

    The State of Baja California (BC) exhibits the highest incidence and prevalence rates of tuberculosis (TB), and multidrug-resistant TB (MDR-TB) in Mexico. However information about the circulation of M. tuberculosis lineages in BC and Mexico as a whole is limited. Here, we describe the genetic relationship and genetic diversity among M. tuberculosis clinical isolates (n=140) collected in BC between October 2009 and April 2011 with other regions of Mexico, the United States, and Latin America. All specimens were genotyped based on 24 mycobacterial interspersed repetitive units (MIRU)-variable number of tandem repeats (VNTR) loci. Population structure and minimum spanning tree (MST) analyses were used to assess the genetic diversity and distribution of BC isolates in comparison to USA and South America strains. Among the nine lineages observed, LAM, Haarlem and S were the most frequent identified in BC. Population structure analysis clustered most BC isolates (41%) into three distinctive groups that included strains from San Diego and South America, whereas other BC strains (22%) clustered with other Mexican strains. A subset of isolates (12%) seemed to be autochthonous of BC, while 25% were cosmopolitan and grouped into multiple clusters. It is highly likely that the TB genetic structure observed in BC is due to human migration. Additional studies are required to determine the mechanism involved in the phylogeographic distribution of M. tuberculosis in Mexico. Implementation of domestic molecular TB surveillance programs is required to better understand the molecular epidemiology of TB not only in the region but at the national level. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Triggered surface slips in southern California associated with the 2010 El Mayor-Cucapah, Baja California, Mexico, earthquake

    Science.gov (United States)

    Rymer, Michael J.; Treiman, Jerome A.; Kendrick, Katherine J.; Lienkaemper, James J.; Weldon, Ray J.; Bilham, Roger; Wei, Meng; Fielding, Eric J.; Hernandez, Janis L.; Olson, Brian P.E.; Irvine, Pamela J.; Knepprath, Nichole; Sickler, Robert R.; Tong, Xiaopeng; Siem, Martin E.

    2011-01-01

    The April 4, 2010 (Mw7.2), El Mayor-Cucapah, Baja California, Mexico, earthquake is the strongest earthquake to shake the Salton Trough area since the 1992 (Mw7.3) Landers earthquake. Similar to the Landers event, ground-surface fracturing occurred on multiple faults in the trough. However, the 2010 event triggered surface slip on more faults in the central Salton Trough than previous earthquakes, including multiple faults in the Yuha Desert area, the southwestern section of the Salton Trough. In the central Salton Trough, surface fracturing occurred along the southern San Andreas, Coyote Creek, Superstition Hills, Wienert, Kalin, and Imperial Faults and along the Brawley Fault Zone, all of which are known to have slipped in historical time, either in primary (tectonic) slip and/or in triggered slip. Surface slip in association with the El Mayor-Cucapah earthquake is at least the eighth time in the past 42 years that a local or regional earthquake has triggered slip along faults in the central Salton Trough. In the southwestern part of the Salton Trough, surface fractures (triggered slip) occurred in a broad area of the Yuha Desert. This is the first time that triggered slip has been observed in the southwestern Salton Trough.

  9. Distribución de aves acuáticas en las lagunas de oxidación de la ciudad de La Paz, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Elvia Margarita Zamora-Orozco

    2007-06-01

    Full Text Available Se determinó la composición taxonómica y la distribución espacial y temporal de aves acuáticas de las lagunas de oxidación (LO, de la ciudad de La Paz, Baja California Sur, México, durante 24 censos quincenales (abril/98marzo/99. Se trata de cinco lagunas, de cinco ha cada una y 17 ha de terrenos aledaños constantemente inundados que sirven como zona de alimentación para el ganado y las aves. Se observaron 123 especies de aves, de las cuales 75 fueron acuáticas. En total se realizaron 46 041 registros (promedio= 1 918 aves/censo. La riqueza y la abundancia estuvieron influenciadas por la migración, principalmente de anátidos y playeros, los primeros fueron el grupo más abundante, debido a su afinidad por cuerpos dulceacuícolas. Los terrenos aledaños fueron los preferidos por los patos vadeadores (Anas y por los playeros. En contraste, dos de las especies más abundantes (Oxyura jamaicensis 12.5 % del total y Fulica americana 8.8 %, restringieron su presencia al espejo de agua. LO presentó un componente aviar propio y atípico, dada la aridez de la región.Distribution of aquatic birds in oxidation lagoons of La Paz city in South Baja California, Mexico. Taxonomic composition, spatial and temporal distribution of aquatic birds in oxidation lagoons (LO of La Paz city in south Baja California, Mexico, were determined during 24 censuses realized in two-week intervals (April/98-March/99. There are five lagoons of 5 Ha each and 17 ha of terrains constantly flooded that serve as feeding areas for cattle and birds. One hundred twenty three species were observed, 75 of which were aquatic birds. A total of 46 041 observations were made (average 1 918 birds/census. Richness and abundance of aquatic birds were influenced mainly by migration of anatids and sandpipers. The first group had the greatest abundance due to its affinity towards fresh water bodies. The terrains were the favorite sites of dabbling ducks (Anas and sandpipers. In

  10. Trace elements in blood of sea turtles Lepidochelys olivacea in the Gulf of California, Mexico.

    Science.gov (United States)

    Zavala-Norzagaray, A A; Ley-Quiñónez, C P; Espinosa-Carreón, T L; Canizalez-Román, A; Hart, C E; Aguirre, A A

    2014-11-01

    This study determined the concentrations of heavy metals in blood collected from Pacific Ridley sea turtles (Lepidochelys olivacea) inhabiting the coast of Guasave, Mexico, in the Gulf of California. The highest reported metal concentration in blood was Zn, followed by Se. Of nonessential toxic metals, As was reported in higher percentage compared to Cd. The concentrations of metals detected were present as follows: Zn > Se > Mn > As > Ni > Cd > Cu. Cd concentration in blood is higher in our population in comparison with other populations of L. olivacea, and even higher in other species of sea turtles. Our study reinforces the usefulness of blood for the monitoring of the levels of contaminating elements, and is easily accessible and nonlethal for sea turtles.

  11. Numerical simulation of the sea breeze, ideal and realistic: Baja California, Mexico case

    Science.gov (United States)

    Colorado, G.; Mateos, E.; Ayala, R.

    2016-12-01

    In studies, with data from weather stations in Bahia de Todos Santos, Baja California, Mexico, was found that the sea-land breeze is an important component of the wind circulation. Therefore, its behaviour was simulated numerically with the WRF model to identify not only the surface field, but the vertical component of this phenomenon, in addition to quantifying the number of events during the year 2010. The model was forced with NARR data, and triple nested meshes were defined, whose smallest nest has a horizontal resolution of 2 km. In parallel to realistic simulation, an idealized numerical experiment was done with the WRF-idealize sea breeze example to verify whether the WRF model can reproduce the sea breeze. In order to do this, three variables were analyzed: temperature, relative humidity and the U component of the wind.

  12. [Prenatal care and hospital maternal mortality in Tijuana, Baja California, Mexico].

    Science.gov (United States)

    Gonzaga-Soriano, María Rode; Zonana-Nacach, Abraham; Anzaldo-Campos, María Cecilia; Olazarán-Gutiérrez, Asbeidi

    2014-01-01

    To describe the prenatal care (PC) received in women with maternal hospital deaths from 2005 to 2011 in Tijuana, Baja California, Mexico. Were reviewed the medical chars and registrations of the maternal deaths by the local Committees of Maternal Mortality. There were 44 maternal hospital deaths. Thirty (68%) women assisted to PC appointments during pregnancy, the average number of PC visits was 3.8 and 18 (41%) had an adequate PC (≥ 5 visits). Six (14%) women didn't know they were pregnant; 19 (43%), 21 (48%) y 4 (9%) maternal deaths were due to direct, indirect obstetric cause or non-obstetric causes. Eighteen (18%), 2 (4 %) and 34 (77%) of the maternal deaths occurred during pregnancy, delivery or puerperium. It is necessary pregnancy women have an early, periodic and systematic PC to identify opportunely risk factors associated with pregnancy complications.

  13. Prenatal care and hospital maternal mortality in Tijuana, Baja California, Mexico.

    Directory of Open Access Journals (Sweden)

    María Rode Gonzaga-Soriano

    2014-01-01

    Full Text Available Objective. To describe the prenatal care (PC received in women with maternal hospital deaths from 2005 to 2011 in Tijuana, Baja California, Mexico. Materials and methods. Were reviewed the medical chars and registrations of the maternal deaths by the local Committees of Maternal Mortality. Results. There were 44 maternal hospital deaths. Thirty (68% women assisted to PC appointments during pregnancy, the average number of PC visits was 3.8 and 18 (41% had an adequate PC (≥ 5 visits. Six (14% women didn’t know they were pregnant; 19 (43%, 21 (48% y 4 (9% maternal deaths were due to direct, indirect obstetric cause or non-obstetric causes. Eighteen (18%, 2 (4 % and 34 (77% of the maternal deaths occurred during pregnancy, delivery or puerperium. Conclusions. It is necessary pregnancy women have an early, periodic and systematic PC to identify opportunely risk factors associated with pregnancy complications.

  14. Management by results in Mexico, 2013-2014. Some effects in Baja California

    Directory of Open Access Journals (Sweden)

    José María Ramos García

    2016-07-01

    Full Text Available This paper examines the results-based management (RBM proposal promoted by the Mexican federal government and how this proposal has been applied. This article presents the theory of management according to its results and its effects on competitiveness and well-being. This article analyzes the conceptual elements of the model and the manners in which this model has been instituted both conceptually and operationally in Brazil, Mexico, and the Mexican state of Baja California. Principal findings include the need to strengthen institutional capacities for RBM to enhance competitiveness and well-being at the government level, internalize a vision of strategic change, and prioritize cultural change to generate efficient transparency, accountability and anti-corruption controls by a transversal focus based on the elements of management.

  15. [Seroprevalence of risk factors associated with rickettsiosis (Rickettsia rickettsii) in humans in Baja California, Mexico].

    Science.gov (United States)

    Field-Cortazares, Jorge; Escárcega-Ávila, Angélica María; López-Valencia, Gilberto; Barreras-Serrano, Alberto; Tinoco-Gracia, Luis

    2015-01-01

    Rickettsiosis caused by Rickettsia rickettsii is capable of infecting vertebrates, including humans. The symptoms are high fever, headache, myalgia, nausea, vomiting, abdominal pain, and cough. Mortality can be up to 30% in untreated patients. To prove the existence of rickettsiosis in Ensenada, Baja California, Mexico, because no human cases have been reported. This observational, cross-sectional, descriptive study included 384 samples of humans in Ensenada, Baja California. Antibodies against R. rickettsii were measured with the kit R. rickettsii ELISA(®) Helica Biosystems, Inc., adapted for use in humans using human IgG conjugate antibodies. To determine the sensitivity and specificity, 32 human samples were submitted to IFA. Specific primers were used for the molecular diagnosis of R. rickettsii in dogs and ticks. The seroprevalence adjusted rickettsiosis in humans was 2.9% (95% CI: 0.8-5.3), seropositivity was not associated with sex, age, occupation, household, dogs, pet deworming program against ticks, the type of yard, and mobility of the dog between home and the street. With substantial agreement of k between ELISA and IFA, it follows that the results of seroprevalence of this work are reliable.

  16. Risks for abuse against pregnant Hispanic women: Morelos, Mexico and Los Angeles County, California.

    Science.gov (United States)

    Castro, Roberto; Peek-Asa, Corinne; García, Lorena; Ruiz, Agustín; Kraus, Jess F

    2003-11-01

    Although violence against women is gaining international attention as a prevention priority, little is known about how risks differ across countries. A comparative study of violence against pregnant Mexican women in Morelos, Mexico, and Latina women in Los Angeles County, California, United States. In 1998 and 1999, women in prenatal clinics were interviewed about psychological abuse and sexual and physical violence by their partner, during and the 1 year prior to the index pregnancy. The overall response rate for Morelos was 99%, with a sample size of 914; Los Angeles County had a response rate of 96.9%, with a sample size of 219. Women in Morelos reported a higher prevalence of violence compared to women in the California (14.8% v 11.9%, respectively). A partner aged child were more than 25 times more likely to be abused during pregnancy than women not reporting this type of abuse. The identification of factors associated with violence against women, especially as they differ by culture and ethnicity, will help clinicians to better identify victims and to design and implement culturally appropriate prevention programs.

  17. Developing a Luminescence Chronology for Fan-terrace Sediments, Los Cabos, Baja California, Mexico

    Science.gov (United States)

    Rhodes, E. J.; Brown, N. D.; Antinao, J.; Huenupi, E. C.; Baker, S. E.; McDonald, E.

    2012-12-01

    Extensive depositional units forming large terrace units within alluvial fans close to the southern tip of Baja California, Mexico, record sedimentation under a very different climatic regime from the present. Dating these sediments presents significant challenges; they contain very sparse organic material suitable for radiocarbon dating; their upper surfaces are heavily bioturbated, in some places eroded and in other locations show signs of continued deposition even after incision and base level fall, rendering them difficult to date using TCN (terrestrial cosmogenic nuclide) methods. Locations that have experienced significant regional tectonic influences associated with rapid erosion (e.g. Transverse Ranges, California, Southern Alps, New Zealand, Himalaya and Tibet) are typically not well-suited for quartz OSL (optically stimulated luminescence) application owing to low signal sensitivity. For this reason, our efforts to develop a chronology for the sandy sediments that characterize these contexts have focussed on IRSL dating of K-feldspar, using newly developed post-infrared IRSL (infra-red stimulated luminescence) approaches. We explore the relative advantages of different techniques, and methods to assess both the degree of incomplete zeroing and signal fading. In particular, we explore how novel single grain IRSL measurements of K-feldspar can be applied to these and similar high energy deposits on timescales ranging from the last 100,000 years to a few decades. Based on our chronology coupled with detailed sedimentological and soil stratigraphy investigations, we are able to exploit these deposits as valuable archives of past environmental and climatic change.

  18. [Bycatch fish species from shrimp industrial fishery in the Gulf of California, Mexico].

    Science.gov (United States)

    López-Martínez, Juana; Herrera-Valdivia, Eloisa; Rodríguez-Romero, Jesús; Hernández-Vázquez, Sergio

    2010-09-01

    Bycatch fish species from shrimp industrial fishery in the Gulf of California, Mexico. The shrimp fishery in the Gulf of California is one the most important activities of revenue and employment for communities. Nevertheless, this fishery has also created a large bycatch problem, principally fish. To asses this issue, a group of observers were placed on board the industrial shrimp fleet and evaluated the Eastern side of the Gulf during 2004 and 2005. Studies consisted on 20kg samples of the capture for each trawl, and made possible a systematic list of species for this geographic area. Fish represented 70% of the capture. A total of 51 101 fish were collected, belonging to two classes, 20 orders, 65 families, 127 genera, and 241 species. The order Perciformes was the most diverse with 31 families, 78 genera, and 158 species. The best represented families by number of species were: Sciaenidae (34) and Paralichthyidae (18) and Haemulidae and Carangidae (16 each). The best represented genera in number of species were Symphurus (nine) and Diplectrum and Cynoscion (six); other important genera were Larimus and Porichthys with five species each. The best represented species in number were Syacium ovale, Pseudupeneus grandisquamis, Haemulopsis nitidos, Diplectrum pacificum, Synodus scituliceps, Balistes polylepis, Eucinostomus currani, Eucinostomus gracilis, Porichthys analis, Chloroscombrus orqueta, Selene peruviana, Orthopristis reddingi, Etropus crossotus, Scorpaena sonorae and Urobatis halleri. The number of recorded species is notably high, compared with demersal fauna of other areas of the Mexican Pacific, such as Gulf of Tehuantepec (178), Nayarit, Michoacán, Guerrero (174, 120 and 166), Jalisco and Colima (161 species), and those of the Western coast of the Baja California Peninsula (220 species).

  19. Geodatabase of the available top and bottom surface datasets that represent the Basin and Range basin-fill aquifers, Arizona, California, Idaho, Nevada, New Mexico, Oregon, and Utah

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This geodatabase includes spatial datasets that represent the Basin and Range basin-fill aquifers in the States of Arizona, California, Idaho, Nevada, New Mexico,...

  20. Helminth parasites of Pseudacris hypochondriaca (Anura: Hylidae) from Baja California, Mexico, with the description of two new species of nematodes.

    Science.gov (United States)

    Martínez-Salazar, Elizabeth A; Falcón-Ordaz, Jorge; González-Bernal, Edna; Parra-Olea, Gabriela; de León, Gerardo Pérez-Ponce

    2013-12-01

    The helminth parasite fauna of the hylid frog Pseudacris hypochondriaca in several localities along the Baja California Peninsula in northwestern Mexico is presented. The helminth fauna consists of 4 species of nematodes (Oswaldocruzia pipiens, a larval form of an Ascaridid, 2 new species belonging to the genera Rhabdias and Cosmocercoides), and 1 species of digenean ( Gorgoderina sp.). The new species of Rhabdias represents the 88th species assigned to the genus and the third species described from Mexican anurans. Also, the species of Cosmocercoides represents the 20th species assigned to the genus and the first representative of this genus described from Mexico.

  1. Diálogo de saberes ambientales entre Europa-América. Agroecosistemas oasianos en Baja California Sur s. XVIII-XX

    Directory of Open Access Journals (Sweden)

    Ortega Santos, Antonio

    2015-06-01

    Full Text Available During two centuries, Oasis Communities of Baja California had been living in a intense connection with their environment. With the arrival of Jesuits, a deep extermination of biocultural heritage and socioenvironmental knowledges of these communities, repopulating of vegetable garden and drylands with people –in many cases, settler from the south of Spain- reconstructing the territorial identity as ranchera to manage the ecosystems under pattern of self-competence and under-consumption, due to the strong environmental constraints of lower california agro-ecosystem. At the beginning of XXIth century, Oasis Communities are fighting against the loss of community heritage, embedded in Eden with enormous bio-cultural dimension, rescuing and keeping crops from Europe with the Jesuits arrival. This frame allow us to draw a colonization process of ecosystems during contemporary age.Desde hace más de dos siglos, las Comunidades Oasianas de Baja California Sur han estado viviendo en íntima conexión con su medio ambiente. Con la llegada de los Jesuitas se produjo un intenso proceso de exterminio biocultural de los saberes sociambientales de esas comunidades, repoblando estas huertas y llanos con población -en muchos casos colonos- procedentes del sur de España-, redimensionado la identidad territorial como ranchera que gestionó los ecosistemas bajo pautas de autosuficiencia y subconsumo, dadas las fuertes constricciones socioambientales de agroecosistemas sudcalifornianos. A inicios del siglo XXI, las comunidades oasianas luchan contra la pérdida de sus saberes comunitarios, enclavados en edenes de enorme potencial biocultural, rescatando y manteniendo los cultivos traídos con la llegada de los jesuitas. Este marco nos permite describir un proceso de colonización de los ecosistemas a lo largo de los dos últimos siglos.

  2. Mexico.

    Science.gov (United States)

    Semaan, Leslie

    The text explores Mexico's history, geography, art, religion, and lifestyles in the context of its complex economy. The text focuses on Mexico's economy and reasons for its current situation. Part I of this teaching unit includes: Teacher Overview, Why Study Mexico, Mexico Fact Sheet, Map of Mexico, the Land and Climate, History, Government,…

  3. Photo series for quantifying forest fuels in Mexico: montane subtropical forests of the Sierra Madre del Sur and temperate forests and montane shrubland of the northern Sierra Madre Oriental

    Science.gov (United States)

    Jorge E. Morfin-Rios; Ernesto Alvarado-Celestino; Enrique J. Jardel-Pelaez; Robert E. Vihnanek; David K. Wright; Jose M. Michel-Fuentes; Clinton S. Wright; Roger D. Ottmar; David V. Sandberg; Andres Najera-Diaz

    2008-01-01

    Single wide-angle and stereo photographs display a range of forest ecosystems conditions and fuel loadings in montane subtropical forests of the Sierra Madre del Sur and temperate forests and montane shrubland of the northern Sierra Madre Oriental of Mexico. Each group of photographs includes inventory information summarizing overstory vegetation composition and...

  4. Subsidence of the Laguna Salada Basin, northeastern Baja California, Mexico, inferred from Milankovitch climatic changes

    Energy Technology Data Exchange (ETDEWEB)

    Contreras, Juan; Martin-Barajas, Arturo [Departamento de Geologia, CICESE, Ensenada Baja California (Mexico); Herguera, Juan Carlos [Division de Oceanologia, CICESE, Ensenada Baja California (Mexico)

    2005-01-15

    Laguna Salada in northern Baja California, Mexico, is an active half-graben product of the trans-tensional tectonics of the Gulf of California. It is sensitive to changes in sediment supply from the Colorado River basin. We present a time series analysis of the upper 980 m of a gamma-ray log from a borehole drilled near the Laguna Salada fault. The power spectrum of the gammaray log resembles the spectrum of {delta}{sup 1}8{omicron} Pleistocene isotopic variations from ice cores and from the deep ocean, known to be strongly controlled by Milankovitch cycles. We correlate {delta}{sup 1}8{omicron} stages with silty and sandy intervals in the log. Downcore ages for the last 780 ky are constrained within {approx}10 kyr. We derive a simple time vs. depth calibration relation for the basin over this time interval. Estimated sedimentation rates at the drill site appear to be constant with a value of {approx}1.6 mm/yr. We propose that this subsidence rate is produced by the Laguna Salada fault. [Spanish] La cuenca de Laguna Salada en el norte de Baja California, Mexico, es un semigraben activo producto de la tectonica ranstensional del Golfo de California. Esta cuenca endorreica es sensible a cambios en sedimentacion por variaciones en el aporte e sedimentos de fuentes cercanas y distales transportados por arroyos de las sierras adyacentes y por el Rio Colorado. Esta cuenca es un sitio excepcional para explorar el uso de cambios climaticos ciclicos como herramienta de datacion y estimar tasas de sedimentacion y subsidencia en el area. Para demostrar esto se presenta un analisis de series de tiempo de un registro de rayos de gama de un pozo geotermico exploratorio perforado adyacente a la falla de Laguna Salada, la cual limita el margen oriental de la cuenca. Los resultados del analisis indican que el espectro de los primeros 980 m del registro de rayos gama tiene una alta coherencia con el espectro de registros isotopicos paleoclimaticos de {delta}{sup 1}8{omicron} del

  5. Public Outreach and Educational Experiences in Mexico and Latin American communities in California

    Science.gov (United States)

    Andres De Leo-Winkler, Mario; Canalizo, Gabriela; Pichardo, Barbara; Arias, Brenda

    2015-08-01

    I have created and applied diverse methods in public outreach at National Autonomous Univerisity of Mexico (UNAM) since 2001.A student-led volunteer astronomical club has been created, the biggest in Mexico. We serve over 10,000 people per year. We have created public outreach activities for the general audience: archeo-astronomical outings, scientific movie debates, conferences, courses, public telescope viewings. We have also worked with juvenile delinquents to offer them scientific opportunities when released from jail.I've also created and worked the social media for the Institute of Astronomy UNAM, which is currently the biggest social media site on astronomy in Spanish in the world. I've created and organized a mass photo exhibition (over 1 million people served) for the Institute of Astronomy, UNAM which was citizen-funded through an online platform, the first of its kind in the country. Together with my colleages, we created workshops on astronomy for children with the Mexican's government funding.I've participated in several radio and television programs/capsules designed to bring astronomy to the general audience, one in particular ("Astrophysics for Dummies") was very successful in nation-wide Mexican radio.I am currently applying all experiences to develop a new public outreach project on astronomy for the University of California - Riverside and its on-campus and surrounding Latin American communities. We are offering new workshops for blind and deaf children. We want to integrate the Latino community to our outreach activities and offer science in their language in a simple and entertaining fashion. We have also successfully applied astrophotography as a course which brings social-science and arts undergraduate students into natural sciences.Sharing experiences, success and failure stories will help new and experienced educators and public outreach professionals learn and better from past experiences.

  6. Individual and community factors contributing to anemia among women in rural Baja California, Mexico.

    Directory of Open Access Journals (Sweden)

    Molly A Moor

    Full Text Available Anemia is a public health concern among women in rural Baja California, Mexico. The purpose of this study was to identify the individual and community factors contributing to the disproportionately high prevalence of anemia among women in this region.A cross-sectional study of 118 women (15-49 years was performed in a rural colonia (small settlement in Baja California, Mexico in 2012. Participants completed a survey comprised of demographic, socioeconomic, health, and dietary questions and provided a capillary blood sample. A portable HemoCue was used to measure hemoglobin and diagnose anemia. Anemic participants provided a venous blood sample for laboratory testing to elucidate the etiology of anemia. Anemic participants received vitamin supplements and nutritional counseling. Assessments of six local tiendas (community grocery stores were performed to ascertain the types of food available for purchase within the community.Prevalence of anemia was 22% among women; laboratory tests revealed iron deficiency was the primary etiology in 80.8% of anemia cases. Other causes of anemia in women included vitamin B-12 deficiency (11.5% and combined iron and vitamin B-12 deficiency (7.7%. Women from low SES households and women enrolled in the government assistance program Prospera were significantly more likely to be anemic (OR = 3.48, 95% CI 1.35-8.98 and OR = 2.49, 95% CI 1.02-6.09, respectively. Vitamin supplementation was significantly more common among non-anemic women (OR = 0.12, 95% CI 0.02-0.94. Dietary assessments showed limited consumption of iron absorption enhancing foods such as fruits and vegetables. Assessments of local tiendas revealed at least one type of meat and citrus fruit available for purchase at each store; however, leafy green vegetables were only available for purchase at one store.All cases of anemia were due to nutritional deficiencies. While vitamin supplementation is a temporary solution, improved individual nutrition

  7. Degree of trace metal pyritization in sediments from the Pacific coast of Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Nava Lopez, Carmen; Huerta Diaz, Miguel Angel [Instituto de Investigaciones Oceanologicas, Ensenada, Baja California (Mexico)

    2001-06-01

    We analyzed sediments from a core collected on the Pacific coast of Baja California, 45 km off the city of Tijuana and at 1257 m water depth (32 Celsius degrees 9.5N , 117 Celsius degrees 8.3W), for trace metal content in two operationally-defined fractions, HCl and pyrite. Our results indicate transference of Cu>Ni>Zn>>Hg y Ag from the HCl to the pyrite fraction. Sediments have degrees of pyritization (DOP) that average 7.2{+-} 4.9% with a maximum value of 18.5%. Average degrees of trace metal pyritization (DTMP) range from 6.2 {+-}2.1% to 83{+-} 8% for Mn and Hg, respectively, although maximum values for some metals were closed to 100%. This transference is apparently a function of the solubility products of metal sulfides and the relative abundances of metals in the HCl fraction, as suggested by the significant correlation (p<0.001) observed between these two parameters and the DTMP of a number of trace metals. A similar correlation was obtained from published data of two cores collected in the Gulf of Mexico. [Spanish] Se analizaron sedimentos de un nucleo recolectado en la costa del Pacifico de Baja California 45 km de la costa de la ciudad de Tijuana y a 1257 m de profundidad del agua (32 grados Celsius 9.5N, 117 grados Celsius 8.3W), para determinar su contenido de metales traza en dos fracciones operacionales definidas HCl y pirita. Los resultados indican una transferencia de Cu>Ni>Zn>>Hg y Ag de la fraccion de HCl a la fase piritica. Los grados de piritizacion (DOP) en los sedimentos promediaron 7.2{+-} 4.9%, con un valor maximo de 18.5%. Los valores promedio de los grados de piritizacion de metales traza (DTMP) abarcaron el intervalo de 6.2 {+-}2.1% a 83{+-}18% para Mn y Hg, respectivamente, aunque los valores maximos para algunos metales estuvieron cercanos al 100%. Esta transferencia aparentemente es funcion de los productos de solubilidad de los sulfuros metalicos y de la abundancia relativa de metales en la fraccion HCl, como sugiere la correlacion

  8. [Sea star (Asteroidea) association structures on the rocky reef in the Gulf of California, Mexico].

    Science.gov (United States)

    Reyes Bonilla, Héctor; González Azcárraga, Adriana; Rojas Sierra, Aracely

    2005-12-01

    Sea stars are invertebrates that play relevant roles in rocky and coral reefs: they occupy different levels in food webs and may act as top predators. There are numerous studies on taxonomy and biogeography of the class in the eastern tropical Pacific, but information about the attributes and composition of its assemblages is scant. The objectives of this study were the examination and comparison of asteroid community structure from four regions of the Gulf of California, Mexico, characterized by the presence of rocky reefs, and the search for possible associations between pairs of species. In August 2004 we visited four locations in the western gulf: Bahia de Los Angeles (29 degrees N), Santa Rosalia (27 degrees N), Loreto (26 degrees N) and La Paz (24 degrees N), and censuses sea stars using 50 m2 belt transects (N=93). Abundance and species richness was estimated, as well as diversity (H'), evenness (J') and taxonomic distinctness (delta*); then, all variables were compared among regions with analysis of variance. In addition, an ordination analysis was run looking for groups of locations with similar faunistic composition. Our results showed that Loreto Bay had the highest richness and abundance of asteroids, probably because it presents a large number of habitats and multiple food sources; these conditions seem to favor the occurrence of rare species and of detritivores. However, there were no significant interregional differences among ecological indices, nor we detected groups of locations singled out because of its species composition. Thus, community structure of sea stars in rocky areas of the Gulf of California is quite homogeneous and do not change with latitude. This is a consequence of the fact that all regions under analysis had the species Phataria unifascialis and Pharia pyramidatus as dominant in number. There were significant positive associations between three pairs of species: apparently competition is not particularly relevant to control sea

  9. Fetal mummification in silky shark (Carcharhinus falciformis from the Gulf of California, Mexico

    Directory of Open Access Journals (Sweden)

    Jonathan Sandoval-Castillo

    2008-06-01

    Full Text Available The aim of this work was the description of fetal mummification in silky shark. During July of 2001 in Santa Maria fishing camp, Gulf of California Mexico, fourteen pregnant female of silky sharks were captured. In all of them the embryos were found to be dehydrated. However, total observations were possible in only two litters. Six embryos in each analyzed litters were found. All the embryos were mummified, complete and without maceration. Because the litters were totally mummificated in several females, it was suggested that fetal mummification was produced by the environmental condition.A mumificação fetal é caracterizada pela desidatração de embriões mortos dentro do útero da mãe. A perda de embriões pode afetar a sustentabilidade da população explorada, tornando o estudo deste fenômeno de suma importância. Em Julho de 2001 quatorze femeas grávidas do tubarão lombo preto foram capituradas durante uma amostragem no campo pesqueiro de Santa Maria, Golfo de California, México. Todas as fêmeas capturadas apresentaram embriões mumificados. Infelizmente, observações detalhadas dos embriões foram possíveis em apenas duas fêmeas. Cada fêmea analizada apresentava seis embriões, todos completamente mumificados e sem maceração. Embriões completamente mumificados foram encontrados em muitas fêmeas, o que sugere que a mumificação fetal desses embriões pode ter sido causada por condições ambientais.

  10. Sources and transport of black carbon at the California-Mexico border

    Science.gov (United States)

    Shores, Christopher A.; Klapmeyer, Michael E.; Quadros, Marina E.; Marr, Linsey C.

    2013-05-01

    At international border areas that suffer from poor air quality, assessment of pollutant sources and transport across the border is important for designing effective air quality management strategies. As part of the Cal-Mex 2010 field campaign at the US-Mexico border in San Diego and Tijuana, we measured black carbon (BC) concentrations at three locations in Mexico and one in the United States. The measurements were intended to support the following objectives: to characterize the spatial and temporal variability in BC, to estimate the BC emission inventory, to identify potential source areas of BC emissions, and to assess the cross-border transport of BC. Concentrations at Parque Morelos, the campaign's supersite, averaged 2.2 μg m-3 and reached a maximum value of 55.9 μg m-3 (1-min average). Sharp, regularly occurring peaks around midnight were suggestive of clandestine industrial activity. BC concentrations were more than two times higher, on average, in Tijuana compared to San Diego. BC and carbon monoxide (CO) were strongly correlated at the three sites in Mexico. The ΔBC/ΔCO ratio of 5.6 ± 0.5 μg m-3 ppm-1 in Tijuana, or 4.7 ± 0.5 μg m-3 ppm-1 when adjusted for seasonal temperature effects to represent an annual average, was comparable to that in other urban areas. Tijuana's emissions of BC were estimated to be 230-890 metric tons per year, 6-23% of those estimated for San Diego. Large uncertainties in this estimate stem mainly from uncertainties in the CO emission inventory, and the lower end of the estimate is more likely to be accurate. Patterns in concentrations and winds suggest that BC in Tijuana was usually of local origin. Under typical summertime conditions such as those observed during the study, transport from Tijuana into the US was common, crossing the border in a northeasterly direction, sometimes as far east as Imperial County at the eastern edge of California.

  11. Estructura de la avifauna durante el periodo invierno-primavera en el Estero Rancho Bueno, Baja California Sur, México Structure of the avifauna during the winter-spring season in Estero Rancho Bueno, Baja California Sur, México

    OpenAIRE

    Edgar Amador; Renato Mendoza-Salgado; Juan Antonio de Anda-Montañez

    2006-01-01

    Mensualmente, de noviembre de 1993 a junio de 1994, se contaron las aves en un ambiente de manglar en Estero Rancho Bueno de la costa occidental de Baja California Sur. Sumaron en total 5965 aves de 56 especies de 10 órdenes y 21 familias. La estacionalidad estuvo definida por 31 residentes, 22 migratorias y tres indeterminadas. La mayoría de las especies se consideran costeras y/o estuarinas; sin embargo, hay algunas terrestres. Existen indicios de que por lo menos 2 especies se reproducen e...

  12. Longitud, peso y sexo del dorado Coryphaena hippurus (Perciformes: Coryphaenidae, del litoral de Sinaloa, Nayarit y Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    J.V. Madrid

    2001-12-01

    Full Text Available Poblaciones de dorado (Pisces fueron muestreadas en Sinaloa, Nayarit y Baja Califonia Sur, México, en 1997. Unos 3211 organismos fueron analizados. Las tallas máximas fueron de 192 cm y 30 Kg. Hay diferentes tallas asociadas a las zonas y épocas climática (P Dolphin fish population data were recorded from landings in Sinaloa, Nayarit and Baja Califonia Sur, Mexico, in 1997. Of 3 211 organisms only 2 812 produced complete biometric data. The maximal length and weight were 192 cm and 30 Kg. The three sampling sites and the climatic periods also were associated with different size (P < 0.05. The covariate analysis of weight and length relationships indicated significative differences (P < 0.05 for total data and by sex. Condition factor was higher throughout the study period in Mazatlán, and the variation was higher, in the spring. The sexual ratio was in Mazatlán was constant, while there were more males in Nayarit in the fall and the spring and in Los Cabos in the spring. There may be population differences, between the central mexican Pacific Coast and the Peninsula of Baja data

  13. El corredor turístico Loreto-Nopoló- Puerto Escondido, Baja California sur, en el contexto de los centros integralmente planeados

    Directory of Open Access Journals (Sweden)

    Rosa Alejandrina De Sicilia Muñoz

    2000-01-01

    Full Text Available El presente trabajo muestra la situación actual del corredor turístico Loreto-Nopoló- Puerto Escondido, Baja California Sur, México. Este Corredor es uno de los cinco Centros Integralmente Planeados (CIP que ideara el Fondo Nacional de apoyo al Turismo, dependiente del gobierno mexicano, en los años setenta. Se presenta una breve reseña histórica de la evolución del turismo en este lugar, su designación como CIP, y se examinan algunas razones por las que este centro no ha tenido el desarrollo que se esperó en un principio.

  14. Daily food intake of Kajikia audax (Philippi, 1887 off Cabo San Lucas, Gulf of California, Mexico Tasa de consumo diario de alimento de Kajikia audax (Philippi, 1887 frente a Cabo San Lucas, golfo de California, México

    Directory of Open Access Journals (Sweden)

    Leonardo A Abitia-Cárdenas

    2011-11-01

    Full Text Available The daily food intake rates of the striped marlin, Kajikia audax (Perciformes: Istiophoridae, were estimated using qualitative and quantitative analyses of their trophic spectrum. We analyzed the stomach contents of 505 striped marlin caught by the sport fishing fleet off Cabo San Lucas, Baja California Sur, Mexico, sampled from October 1987 through December 1989. The most important preys were chub mackerel (Scomber japonicus, California pilchard (Sardinops caeruleus, and jumbo squid (Dosidicus gigas; together these represented ~55% of the striped marlin diet. The daily food consumption was estimated to be 2 kg per day, or ~3.6% of the mean body weight of K. audax. The total biomass of the prey consumed by the striped marlin during the 27 months of sampling around Los Cabos was estimated at 24.8 ton, of which the chub mackerel represented ~29% (7.2 ton, California pilchard just under 16% (3.9 ton, and jumbo squid ~10% (2.5 ton. The feeding habits of K. audax are discussed in terms of the distribution of the epipelagic (neritic and oceanic zones, demersal, and benthic prey, confirming that striped marlin migrate vertically and horizontally in search of their food.Se estimó la tasa de consumo diario de alimento del marlín rayado Kajikia audax (Perciformes: Istiophoridae, sobre la base de análisis cualitativos y cuantitativos de su espectro trófico. Se analizó el contenido estomacal de 505 ejemplares capturados por la flota deportiva frente a Cabo San Lucas, Baja California Sur, México muestreados de octubre 1987 a diciembre 1989. Las presas más importantes fueron la macarela del Pacífico (Scomber japonicus, sardina monterrey (Sardinops caeruleus y calamar gigante (Dosidicus gigas, que en conjunto representaron aproximadamente el 55% de la dieta. La tasa de consumo de alimento fue estimado en 2 kg diarios, lo cual representó aproximadamente el 3,6% del peso corporal de K. audax. La biomasa total de presas consumidas por el marlín rayado

  15. Marine and brackish-water molluscan biodiversity in the Gulf of California, Mexico

    Directory of Open Access Journals (Sweden)

    Michel E. Hendrickx

    2007-12-01

    Full Text Available A database containing taxonomic, distributional and ecological data of 2194 species of marine molluscs (1528 Gastropoda, 565 Bivalvia, 59 Polyplacophora, 21 Scaphopoda, 20 Cephalopoda, and one Monoplacophora known to the Gulf of California, Mexico, was used to analyse their latitudinal and bathymetric distribution, to define their substrate preferences, and to elaborate a biodiversity model for the study area. The model was based on a comparison between the set of data associated with each species (i.e., depth range, associated substrates and geographic distribution within the Gulf and the environmental conditions prevailing in the Gulf (i.e., depth and substrate, using a georeferenced grid of 2 x 2 nautical miles. Results are presented as predictive biodiversity distribution maps for the major molluscan groups. Putative biodiversity ranges were defined using a percentage accumulative system with 20% classes. As expected, the highest biodiversity occurs along the coastline and around the islands. A south-north biodiversity gradient is observed, although it is less evident between the southern and central Gulf.

  16. Relación entre las capturas de Megapitaria squalida (Bivalvia: Veneridae y la temperatura superficial del mar en la Bahía de la Paz, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Mariana Vázquez Hurtado

    2011-03-01

    Full Text Available La almeja chocolate Megapitaria squalida es un recurso pesquero con creciente importancia en el noroeste de México al registrarse un incremento en los volúmenes de captura. Sin embargo, esta pesquería ha observado variaciones importantes en las capturas que podrían estar relacionadas con factores ambientales. Se obtuvieron datos mensuales de producción de M. squalida durante 2002- 2005 y se estimaron series de tiempo de temperatura superficial del mar en la Bahía de La Paz B.C.S. a partir de imágenes mensuales derivadas del sensor MODIS-Aqua. Los resultados indican una relación positiva significativa entre la temperatura superficial del mar y los volúmenes de captura, razón por la cual nuestro trabajo tiene como objetivo estudiar las relaciones entre capturas de Megapitaria squalida (Bivalvia: Veneridae y la temperatura superficial del mar en La Bahía de la Paz, Baja California Sur, México.Megapitaria squalida (Bivalvia: Veneridae fishery landings and temperature relationship in Bahía de la Paz, México. The clam Megapitaria squalida is a fishing resource with increasing importance in Northwestern Mexico. Nevertheless, this fishery has shown important variations that could be related to environmental factors. To assess this, monthly landings of M. squalida were analyzed during 2002-2005 for Bahía de La Paz, B.C.S., and were related with monthly time series of sea surface temperature, derived from MODIS-Aqua Sensor. The results showed a positive and significant relationship between sea surface temperature and clam landings. The likely impact of anomalous conditions of sea temperature on this resource is discussed. Rev. Biol. Trop. 59 (1: 151-157. Epub 2011 March 01.

  17. Modeling of Trans-boundary Transport of Air Pollutants in the California-Mexico Border Region during Cal-Mex 2010

    Science.gov (United States)

    Bei, N.; Zavala, M. A.; Lei, W.; Li, G.; Molina, L. T.

    2010-12-01

    The US and Mexico share a common air basin along the ~200 km border between California and Baja California. The economical activities in this region are heavily influenced by the international trade and commerce between Mexico and the US that mainly occurs through the borders of the sister cities of San Diego-Tijuana and Calexico-Mexicali. The diversity and differences in the characteristics of emissions sources of air pollutants in the California-Mexico border region make this an important area for the study of the chemistry and trans-boundary transport of air pollutants. During May-June of 2010, the Cal-Mex 2010 field campaign included a series of measurements aimed at characterizing the emissions from major sources in the California-Mexico border region and assessing the possible impacts of these emissions on local and regional air quality. In this work we will present the results of the use of the Comprehensive Air quality model with extensions (CAMx) in a modeling domain that includes the sister cities of San Diego-Tijuana and Calexico-Mexicali for studying events of trans-boundary transport of air pollutants during Cal-Mex 2010. The measurements obtained during the Cal-Mex 2010 field campaign are used in the evaluation of the model performance and in the design of air quality improvement policies in the California-Mexico border region.

  18. Valoración socioambiental de los recursos naturales: el caso de los recursos minerales en la parte central de Baja California Sur, México

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    Luis F. Beltrán Morales

    2012-02-01

    Full Text Available Se seleccionaron 15 localidades ubicadas en el radio de influencia de dos depósitos evaluados de fosfato, esto con la finalidad de aplicar el método de valoración contingente del recurso y su medio ambiente: el depósito de Tembabichi en el margen del Golfo de California y el depósito de Santo Domingo en la costa del Pacífico en Baja California Sur, México. Se encontró una disposición media a pagar por los habitantes del área de estudio de $29.77 pesos mensuales para colaborar con el medio ambiente de su región. Hipotéticamente se daría una valoración contingente en el total del área de estudio de $227 859.58 pesos mensuales, es decir, $2 734 314.9 pesos anuales. Es una cantidad considerable de recursos para contribuir a mejoras en el medio ambiente por comunidades rurales con signos de marginación socioeconómica.

  19. PATHOGENIC LEPTOSPIRA SEROVARS IN FREE-LIVING SEA LIONS IN THE GULF OF CALIFORNIA AND ALONG THE BAJA CALIFORNIA COAST OF MEXICO.

    Science.gov (United States)

    Avalos-Téllez, Rosalía; Carrillo-Casas, Erika M; Atilano-López, Daniel; Godínez-Reyes, Carlos R; Díaz-Aparicio, Efrén; Ramírez-Delgado, David; Ramírez-Echenique, María F; Leyva-Leyva, Margarita; Suzán, Gerardo; Suárez-Güemes, Francisco

    2016-04-28

    The California sea lion ( Zalophus californianus ), a permanent inhabitant of the Gulf of California in Mexico, is susceptible to pathogenic Leptospira spp. infection, which can result in hepatic and renal damage and may lead to renal failure and death. During summer 2013, we used the microscopic agglutination test (MAT) to investigate the prevalence of anti-Leptospira antibodies in blood of clinically healthy sea lion pups from seven rookery islands on the Pacific Coast of Baja California (Pacific Ocean) and in the Gulf of California. We also used PCR to examine blood for Leptospira DNA. Isolation of Leptospira in liquid media was unsuccessful. We found higher antibody prevalence in sea lions from the rookery islands in the gulf than in those from the Pacific Coast. Antibodies against 11 serovars were identified in the Gulf of California population; the most frequent reactions were against serovars Bataviae (90%), Pyrogenes (86%), Wolffi (86%), Celledoni (71%), and Pomona (65%). In the Pacific Ocean population, MAT was positive against eight serovars, where Wolffi (88%), Pomona (75%), and Bataviae (70%) were the most frequent. Serum samples agglutinated with more than one Leptospira serovar. The maximum titer was 3,200. Each island had a different serology profile, and islands combined showed a distinct profile for each region. We detected pathogenic Leptospira DNA in 63% of blood samples, but we found no saprophytic Leptospira. Positive PCR results were obtained in blood samples with high and low MAT titers. Together, these two methods enhance the diagnosis and interpretation of sea lion leptospirosis. Our results may be related to human activities or the presence of other reservoirs with which sea lions interact, and they may also be related to sea lion stranding.

  20. Precursory scale increase and long-term seismogenesis in California and Northern Mexico

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    D. Rhoades

    2002-06-01

    Full Text Available A sudden increase in the scale of seismicity has occurred as a long-term precursor to twelve major earthquakes in California and Northern Mexico. These include all earthquakes along the San Andreas system during 1960-2000 with magnitude M ?6.4. The full list is as follows: Colorado Delta, 1966, M 6.3; Borrego Mt., 1968, M 6.5; San Fernando, 1971, M 6.6; Brawley, 1979, M 6.4; Mexicali, 1980, M 6.1; Coalinga, 1983, M 6.7; Superstition Hills, 1987, M 6.6; Loma Prieta, 1989, M 7.0; Joshua Tree, 1992, M 6.1; Landers, 1992, M 7.3; Northridge, 1994, M 6.6; Hector Mine, 1999, M 7.1. Such a Precursory Scale Increase ( was inferred from the modelling of long-term seismogenesis as a three-stage faulting process against a background of self-organised criticality. The location, onset-time and level of ? are predictive of the location, time and magnitude of the future earthquake. Precursory swarms, which occur widely in subduction regions, are a special form of ? ; the more general form is here shownto occur frequently in a region of continental transform. Other seismicity precursors, including quiescence and foreshocks, contribute to or modulate the increased seismicity that characterises ? . The area occupied by ? is small compared with those occupied by the seismicity precursors known as AMR, M8 and LURR. Further work is needed to formulate as a testable hypothesis, and to carry out the appropriate forecasting tests.

  1. Maternal perception of child weight among Mexicans in California and Mexico.

    Science.gov (United States)

    Rosas, Lisa G; Harley, Kim G; Guendelman, Sylvia; Fernald, Lia C H; Mejia, Fabiola; Eskenazi, Brenda

    2010-11-01

    The prevalence of childhood overweight is high in Mexican immigrant communities in the United States. Understanding mother's perceptions of child weight in immigrants' country of origin may help to understand this high prevalence. The goal of this study was to examine and compare mothers' perception of weight in Mexico (MX) and in an immigrant community in California (CA). We assessed perceptions of child weight using a pictorial scale with 314 mothers of 5-year-old children in MX and 60 mothers of 5 year-old-children in CA. We compared maternal reports with children's objectively measured weight. Using chi-square and Analysis of Variance, we investigated associations of maternal perception of and satisfaction with weight according to socio-demographic characteristics. Mothers were more likely to underestimate their children's weight in CA than in MX. On average, CA mothers wanted their children to be smaller than they currently were and mothers in MX wanted their children to be bigger than they currently were. This differed by weight status in CA with mothers of normal weight and at-risk-for-overweight children wanting them to be bigger and mothers of overweight children wanting them to be smaller. In order for programs to be effective, mothers must be able to recognize their children as overweight and want to address it. Because underestimation of weight and a desire for a larger size is common in this population, programs to address overweight may be more effective if they focus on alternative benefits of weight control strategies, such as healthy child development.

  2. Parallel rapid HIV testing in pregnant women at Tijuana General Hospital, Baja California, Mexico.

    Science.gov (United States)

    Viani, Rolando M; Araneta, Maria Rosario G; Spector, Stephen A

    2013-03-01

    The objectives of this study were to evaluate the performance of parallel rapid HIV testing and the presence of HIV-associated risk factors in pregnant women with unknown HIV status in Baja California, Mexico. Pregnant women attending the delivery unit or the prenatal clinic at Tijuana General Hospital had blood drawn for parallel rapid HIV testing with Determine™ HIV-1/2 and Uni-Gold™ Recombigen(®) HIV. The parallel rapid HIV test performance was compared to the enzyme immunoassay (EIA) and western blot. From September 2007 to July 2008, 1,383 (94%) of 1,464 women in labor and 1,992 (96%) of 2,075 women in prenatal care were enrolled. The HIV seroprevalence among women screened during labor (19/1,383, 1.37%, 95% CI: 0.85-2.18%) was significantly higher compared to those seeking prenatal care (5/1,992, 0.25%, 95% CI: 0.09-0.62%; ppositive by parallel rapid HIV testing 24 had a positive confirmatory western blot and one (0.03%) was confirmed as false positive. Additionally, two (0.06%) women had parallel rapid HIV discordant testing results; both tested negative by western blot. All women who tested negative by rapid testing had negative results on pooled EIA antibody testing. The overall sensitivity, specificity, and positive and negative predictive values of parallel rapid HIV testing were 100%, 99.9%, 96%, and 100%, respectively. These findings document a very high acceptance rate and an excellent performance of the parallel rapid HIV testing strategy during pregnancy.

  3. Calculation of the Rate of M>6.5 Earthquakes for California and Adjacent Portions of Nevada and Mexico

    Science.gov (United States)

    Frankel, Arthur; Mueller, Charles

    2008-01-01

    One of the key issues in the development of an earthquake recurrence model for California and adjacent portions of Nevada and Mexico is the comparison of the predicted rates of earthquakes with the observed rates. Therefore, it is important to make an accurate determination of the observed rate of M>6.5 earthquakes in California and the adjacent region. We have developed a procedure to calculate observed earthquake rates from an earthquake catalog, accounting for magnitude uncertainty and magnitude rounding. We present a Bayesian method that corrects for the effect of the magnitude uncertainty in calculating the observed rates. Our recommended determination of the observed rate of M>6.5 in this region is 0.246 ? 0.085 (for two sigma) per year, although this rate is likely to be underestimated because of catalog incompleteness and this uncertainty estimate does not include all sources of uncertainty.

  4. Correlation between seismicity and the distribution of thermal and carbonate water in southern and Baja California, United States and Mexico

    Science.gov (United States)

    Gastil, Gordon; Bertine, Kathe

    1986-04-01

    A comparison of the distribution of thermal and thermal-related springs and wells in southern California, United States, and Baja California, Mexico, with the abundance of earthquakes of magnitude 4 or greater shows as close a relationship between thermal waters and the distribution of seismicity as to the distribution of active faults. It appears that the distribution of thermal water variations in the geothermal gradient in turn influences the stress accumulation capability of the rocks at depth. Thus, areas with abundant thermal waters (and hence steep geothermal gradients) release stress by frequent moderate earthquakes; areas lacking thermal waters, such as the central Transverse Ranges, accumulate stresses that are released by infrequent large earthquakes.

  5. Distribución espacial y temporal de aves playeras (Orden: Charadriiformes en Laguna San Ignacio, Baja California Sur, México

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    Luis Francisco Mendoza

    2013-03-01

    Full Text Available Con la pérdida o degradación de humedales han declinado las poblaciones de algunas especies tales como las aves playeras. En vista de que ha crecido el interés internacional por los estudios ecológicos sobre estas especies, se determinó la abundancia, distribución y riqueza espacio-temporal de las aves playeras en Laguna San Ignacio, Península de Baja California. Se realizaron 12 censos mensuales (octubre 2007-septiembre 2008 en el perímetro interno de la laguna; la cual se dividió en cuatro zonas, dos al norte y dos al sur. Temporalmente las abundancias menores se presentaron en mayo (1 585 aves y las mayores en octubre (47 410. Las especies más abundantes fueron: el picopando canelo (Limosa fedoa; 55% de los registros totales, el playero occidental (Calidris mauri; 23% y el playero pihuiuí (Tringa semipalmata; 10%. Estas especies fueron más abundantes en otoño. El picopando canelo y el playero pihuiuí estabilizaron sus números en invierno y primavera y estuvieron presentes en verano en bajos números, el playero occidental mostró oscilaciones notorias. Se presentan los primeros reportes del playero rojizo del Pacifico (Calidris canutus roselaari para la zona. La riqueza y abundancia estuvieron influenciadas temporal y espacialmente por las aves migratorias. Las mayores abundancias se presentaron al sur de la laguna, probablemente por la disponibilidad del alimento. Los resultados presentes permitieron incluir al área en la Red Hemisférica de Reservas para las Aves Playeras como sitio de importancia internacional.

  6. Estructura de la comunidad y asociación de las aves acuáticas con la heterogeneidad espacial del complejo lagunar Bahía Magdalena-Almejas, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Bulmara Zárate-Ovando

    2008-03-01

    Full Text Available Para probar la hipótesis que la heterogeneidad espacial determina la diversidad de aves acuáticas en un humedal costero, comparamos la densidad, diversidad y composición de especies de aves acuáticas entre habitats y otras unidades de paisaje del complejo Bahía Magdalena-Almejas, Baja California Sur, México. Se realizaron censos de aves acuáticas en 329 segmentos de habitat de la línea de costa interna del complejo lagunar, desde febrero 2002 hasta febrero 2003. La densidad de aves fue mayor en invierno y otoño en las tres lagunas del área de estudio; de las zonas, la densidad fue mayor en la costa insular; y de los habitats en playa arenosa y dunas pero en los pocos segmentos de sustrato antrópico la densidad fue alta. La diversidad fue significativamente mayor en otoño; en Canal Santo Domingo; en la costa peninsular; y de los habitats en manglar-dunas y manglar. La modificación del habitat natural costero y el disturbio por tránsito de embarcaciones no tuvieron influencia en la densidad o diversidad de aves acuáticas, pero la riqueza acumulada mayor ocurrió en las costas bien conservadas y sin disturbio. El análisis de la composición de especies mostró diferencias entre las asociaciones de Canal Santo Domingo y Bahía Magdalena. El ambiente pelágico y el manglar tuvieron diferencia mayor en la composición de especies con respecto a las asociaciones de los demás habitats, tales diferencias en elencos de especies por habitat sugieren que la comunidad de aves está estructurada de acuerdo a los recursos naturales disponibles de las lagunas, zonas y habitats, en relación con la complejidad estructural de las unidades de paisaje. Las condiciones ecológicas del complejo lagunar ocasionan que las aves acuáticas piscívoras sean el grupo dominante de esta comunidad.Community structure and association of waterbirds with spatial heterogeneity in the Bahía Magdalena-Almejas wetland complex, Baja California Sur, Mexico. To test

  7. Source Functions and Path Effects from Earthquakes in the Farallon Transform Fault Region, Gulf of California, Mexico that Occurred on October 2013

    Science.gov (United States)

    Castro, Raúl R.; Stock, Joann M.; Hauksson, Egill; Clayton, Robert W.

    2017-06-01

    We determined source spectral functions, Q and site effects using regional records of body waves from the October 19, 2013 ( M w = 6.6) earthquake and eight aftershocks located 90 km east of Loreto, Baja California Sur, Mexico. We also analyzed records from a foreshock with magnitude 3.3 that occurred 47 days before the mainshock. The epicenters of this sequence are located in the south-central region of the Gulf of California (GoC) near and on the Farallon transform fault. This is one of the most active regions of the GoC, where most of the large earthquakes have strike-slip mechanisms. Based on the distribution of the aftershocks, the rupture propagated northwest with a rupture length of approximately 27 km. We calculated 3-component P- and S-wave spectra from ten events recorded by eleven stations of the Broadband Seismological Network of the GoC (RESBAN). These stations are located around the GoC and provide good azimuthal coverage (the average station gap is 39°). The spectral records were corrected for site effects, which were estimated calculating average spectral ratios between horizontal and vertical components (HVSR method). The site-corrected spectra were then inverted to determine the source functions and to estimate the attenuation quality factor Q. The values of Q resulting from the spectral inversion can be approximated by the relations Q_{{P}} = 48.1 ± 1.1 f^{0.88 ± 0.04} and Q_{{S}} = 135.4 ± 1.1 f^{0.58 ± 0.03} and are consistent with previous estimates reported by Vidales-Basurto et al. (Bull Seism Soc Am 104:2027-2042, 2014) for the south-central GoC. The stress drop estimates, obtained using the ω2 model, are below 1.7 MPa, with the highest stress drops determined for the mainshock and the aftershocks located in the ridge zone. We used the values of Q obtained to recalculate source and site effects with a different spectral inversion scheme. We found that sites with low S-wave amplification also tend to have low P-wave amplification

  8. The impact in the early years of the Oportunidades program by type of poverty in Mexico and Baja California, 2002–2006

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    Joaquín Bracamontes Nevárez

    2014-11-01

    Full Text Available This paper shows a limited impact of the Oportunidades program in reducing poverty in Mexico and Baja California during the study period (2002–2006, which is due to insufficient resources and the exclusion of poor households. In the country the three types of poverty had a modest reduction and in Baja California capabilities poverty declined slightly, but the food and heritage poverty increased despite the program.

  9. Caracterización espacial y biogeográfica de las asociaciones de macroalgas de Bahía del Rincón,Baja California Sur,México

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    R Riosmena-Rodríguez

    2005-06-01

    Full Text Available Se caracterizó la flora marina de la zona de Bahía del Rincón -La Rivera por medio de prospecciones intensivas en diferentes localidades a varias profundidades. Además, se realizó un análisis intenso de la literatura y por este mismo medio la determinación de las afinidades geográficas de las especies. En total se encontraron 72 especies, donde la mayor proporción (62% correspondió a las algas rojas. En el caso de las afinidades biogeográficas se observó que la mayor proporción varió en función de la división, donde para algas cafés las predominantes fueron de naturaleza tropical/ endémica y para las algas rojas fueron las templadas/ cosmopolitas. Espacialmente se encontró una alta similitud entre las zonas someras estudiadas más no así entre las someras y profundas donde existen diferencias significativas. En el caso de la zona intermareal se determinaron diferencias significativas con áreas submareales y entre sitios de la zona somera y profunda basados en las abundancias de los principales taxa. Con base en los resultados se sugiere que existen diferencias verticales en reclutamiento y desarrollo de las poblaciones en relación a su distribuciónSpatial and biogeographic characterization of macroalgal assemblages from Bahía del Rincón, Baja California Sur, Mexico.Macroalgal studies in Baja California Sur have dealt mainly with occurrence and seasonality, but some areas are poorly known even for these basic data. Bahía del Rincón-La Rivera is an important high-productivity fisheries area where coastal infrastructure development is under way. A spatial characterization of the marine flora from Bahía del Rincón-La Rivera was done by intensive sampling at different depths and localities with skin and SCUBA diving. At least 500m² were surveyed in each site. Additionally, quantitative sampling was done in ten random 25 cm² quadrates per site. In the intertidal section, density and cover estimates were used. We also

  10. Effects of Selective Logging on Birds in the Sierra de Coalcoman, Sierra Madre del Sur, Michoacan, Western Mexico

    Science.gov (United States)

    Jose Fernando Villaseñor; Neyra Sosa; Laura Villaseñor

    2005-01-01

    In order to determine the effects of selective logging on pine-oak forest?s bird communities in central-western Mexico, we gathered information through 10-min point counts in plots without wood extraction and sites logged at different times in the past (1, 4, and 8 years). We did not find evidences to argue for effects of logging on bird communities; the study plots...

  11. New geographic and depth records for deep-water mollusks in the Gulf of California, Mexico Nuevos registros geográficos y batimétricos para moluscos de mar profundo en el golfo de California, México

    OpenAIRE

    Pablo Zamorano; Hendrickx, Michel E; Arturo Toledano-Granados

    2007-01-01

    Six oceanographic cruises (Talud IV-IX) were made in the southern Gulf of California aboard the R/V El Puma of the Universidad Nacional Autónoma de México. A total of 56 species of deep-sea mollusks were identified, of which 16 (13 Bivalvia, 2 Gastropoda, 1 Scaphopoda) represent either a new geographic or bathymetric record, or both.A partir de 6 campañas oceanográficas (Talud IV-IX) realizadas en el sur del golfo de California a bordo del B/O "El Puma" de la Universidad Nacional Autónoma de ...

  12. Evidence for a second impactor at the K-Pg Boundary in Baja California, Mexico

    Science.gov (United States)

    Santa Catharina, Amanda; Kneller, Benjamin Charles; Charao Marques, Juliana; McArthur, Adam Daniel; Kane, Ian Antony; Silvestre Cevallos Ferriz, Sergio Rafael

    2017-04-01

    Controversies remain regarding the trigger, or triggers, of the Cretaceous/Paleogene Mass Extinction. The Chicxulub Impact and the Deccan Volcanism are the main candidates, but discussions about the timing of these events and the magnitude of their effects on the biota are ongoing. Data collected around the globe suggests that profound alterations in the biosphere occurred at this interval, and locations in the Northeastern Atlantic margin and the Gulf of Mexico show evidences of tsunamis and mass waste deposits directly associated with the Chicxulub Impact. Close to El Rosario, Baja California, an enigmatic stratigraphic succession spanning this interval occurs. The succession is distinct from the normal submarine slope deposits in this region and consists of (1) 30 m thick muddy debrites, rich in terrestrial material including fossilized tree trunks up to 2m long and with evidence of exposure to fires, glassy tektites and a horizon rich in gastropods, bivalves, and fragments of corals; (2) an up to 20 m thick coarse grained tuffaceous interval, andesitic in composition, within a channel-like geometry cutting into the debrites, with lapilli (ranging from 1 to 15 cm in size) in discrete sets, fossilized tree trunks close to the base, tektites and shocked quartz; and (3) muddy debrites interbedded with tuffaceous lenses that become less frequent up section. This succession sits between hemipelagic slope deposits, with an abrupt basal contact onto Upper Maastrichtian mudstones and a gradational top, which represents a stabilisation and return to the typical sedimentation environment, with Danian fauna and flora. We believe unit 1 represents material transported onto the slope by the seismic activity caused by the impact of a bolide, which destabilised the coastal region. The tuffaceous channelized unit has been dated (SHRIMP U-Pb in zircons), and its age is indistinguishable from the proposed ages for the K-Pg Boundary. No volcanic activity of this age has been

  13. Lanthanide behavior in hypersaline evaporation ponds at Guerrero Negro, Baja California, Mexico - an environment with halophiles

    Science.gov (United States)

    Choumiline, K.; López-Cortés, A.; Grajeda-Muñoz, M.; Shumilin, E.; Sapozhnikov, D.

    2013-12-01

    Lanthanides are known, in some cases, to be sensitive to changes in water column or sediment chemistry, a fact that allows them to be used as environmental fingerprints. Nevertheless, the behavior of these elements in hypersaline environments is insufficiently understood, especially in those colonized by bacteria, archaea and eukarya halophiles. Extreme environments like the mentioned exist in the artificially-controlled ponds of the 'Exportadora de Sal' salt-producing enterprise located in Guerrero Negro (Baja California, Mexico). Sediment cores from various ponds were collected, subsampled and measured by ICP-MS and INAA. This allowed differencing the behavior of lanthanides and trace elements under a water column salinity gradient along the evaporation sequence of ponds. Sediment profiles (30 mm long), obtained in Pond 5, dominated by Ca and Mg precipitation and at the same time rich in organic matter due to bacterial mat presence, showed highs and lows of the shale-normalized patterns along different in-core depths. Two groups of elements could be distinguished with similar trends: set A (La, Ce, Pr and Nd) and set B (Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu). The first 'group A' had two prominent peaks at 15 mm and around 22 mm, whereas the 'group B' showed only slight increase at 15 mm and none at 22 mm. Microscopic analyses of prokaryotic cells of a stratified mat in Pond 5 (collected in 2004) showed filamentous bacteria and cyanobacteria with a cell abundance and morphotype richness maxima of prokaryotic cells in a chemocline from 3 mm to 7 mm depth which co-exists nine morphotypes of aerobic and anaerobic prokaryotes Microcoleus chthonoplastes, Leptolyngbya, Cyanothece, Geitlerinema, Spirulina, Chloroflexus, Beggiatoa, Chromatium and Thioploca. Below the 7 mm depth, oxygenic photosynthesis depletes and sulfur reducing compounds increase. The highs of the shale-normalized lanthanide contents of the 'group A' (at 15 mm depth) seem to correlate with the

  14. Synthesis of gravity, magnetic and thermal studies at the Las Tres Virgenes geothermal zone, Baja California Sur, Mexico. Sintesis de los estudios de gravimetria, magnetometria y termometria en la zona geotermica de Las Tres Virgenes, Baja California Sur, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Estrada, Gerardo (Departamento de Exploracion, Gerencia de Proyectos Geotermoelectricos de la Comision Federal de Electricidad, Morelia (Mexico)); Gonzalez Lopez, Macario (Residencia General de Cerro Prieto, Mexicali (Mexico))

    1998-01-15

    Las Tres Virgenes geothermal zone is located in the NE-SW central sector of a sigmoidal basin that regionally has a NW-SE trend. In the local deepest zone there is a NE-SE granodioritic basement horst acting as hydrologic barrier, that makes the fluids flow up. After moving in a direction parallel to the local horst, waters continue its regional SE-NW movement controlled by regional tectonics. The flanks of the granodioritic basement horst, and local N-S faulting act as fluid paths in the hydrothermal zone, but regional NW-SE regional faults determine the general flow direction. Both regional and local tectonics show magnetic evidences of the emplacement of magmatic bodies of intermediate to basic composition. Those along NW-SE trends are more noticeable but we consider they are not the present day heat source. Intermediate magmatism along NE-SW local trend seems to be less extensive but it is younger, so, we consider it constitutes the heat source of the hydrothermal system. Thermal data suggest that the heat source is located below the volcanic chain toward the S or SW of the wells, phenomena related with the general displacement of magmatism from NE to SW along the volcanic chain. However, recent intensive faulting permits a higher permeability in the northern sector in which there are slightly smaller temperatures but at shallower depths and with higher flow rates.

  15. Interacciones de pesquerías ribereñas en Bahía Magdalena-Almejas, Baja California Sur

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    Miguel A. Ojeda Ruiz de la Peña

    2012-01-01

    Full Text Available Con el fin de aportar al desarrollo de un modelo conceptual sobre la pesca ribereña o artesanal en el área de Bahía Magdalena-Almejas, Baja California Sur, se jerarquizó la importancia de 14 pesquerías de la región. La calificación se basó en un análisis cualitativo por puntos y en la estimación de un índice de importancia relativa, con indicadores como los promedios de captura, valor y frecuencia de registro de especies objetivo en desembarcos de embarcaciones menores, de 1998 a 2009; entre ellas están: almeja catarina, escama, camarón, callo de hacha, tiburón, jaiba, calamar, almeja pata de mula, rayas, lisa, pulpo, abulón, langosta y caracol chino. La interacción temporal entre varias de ellas es controlada por vedas oficiales, pero cuando ocurre se reconocen posibles efectos por pesca incidental e ilegal y modificaciones al ecosistema.

  16. Ecología trófica del pez Arothron meleagris (Tetraodontiformes: Tetraodontidae en el arrecife de Los Frailes, Baja California Sur, México

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    Xchel G Moreno

    2009-06-01

    Full Text Available Con la finalidad de determinar los hábitos alimenticios del tamboril de oro Arothron meleagris, así como sus posibles variaciones de alimentación por talla y sexo, se realizaron muestreos mensuales de noviembre 2004 a octubre 2005, en el arrecife de Los Frailes, Baja California Sur, México. Se capturaron un total de 101 ejemplares, en los cuales todos los estómagos contenían alimento. Se aplicó el índice de importancia relativa (IIR para determinar los principales categorías alimenticias (ítems, los cuales fueron: Echinometra vanbrunti (26.25 %, Porifera (12.63 %, Pocillopora spp. (11.84%, Bryozoa (5.37 % y Porites spp. (4.83 %. El índice de Levin indica baja amplitud del nicho trófico (Bi= 0.12 por lo que se le puede considerar como un depredador especialista con marcadas preferencias hacia algunos tipos alimentarios. El índice de Morisita-Horn indicó que existe un traslape alto entre las dietas por sexo (hembras y machos o = 0.78, temporadas (cálida y fría o = 0.95 y entre tallas (chica y mediana o = 0.94, chica y grande o = 0.74, mediana y grande o = 0.83.

  17. Disponibilidad y uso del agua en el oasis de los Comondú, Baja California Sur: retos y oportunidades para el desarrollo rural

    Directory of Open Access Journals (Sweden)

    Alba E. Gámez

    2014-01-01

    Full Text Available el desarrollo en las zonas áridas está estrechamente re - lacionado con la disponibilidad y calidad del recurso agua tanto para uso humano como productivo. Este artículo se refiere a su estado actual, disponibilidad y uso en San Mi - guel y San José de Comondú, dos comunidades-oasis de Baja California Sur, México, en el contexto de una política pública que promueve su crecimiento con base en la ex - plotación de su potencial turístico. Con esto se pretende ofrecer un marco de referencia para comprender la cultu - ra ambiental y de manejo hídrico en esas poblaciones, así como ofrecer opciones para un mejor uso de este recurso en una zona vulnerable, que es representativa de localida - des sudcalifornianas aisladas, pero en vías de integración a los procesos económicos y de urbanización que se viven en la entidad.

  18. Four new cestode species from the spiral intestine of the round stingray, Urobatis halleri, in the Northern Gulf of California, Mexico

    Science.gov (United States)

    Megan M. Friggens; Donald W. Duszynski

    2005-01-01

    The spiral intestines of 40 specimens of Urobatis halleri from the northern Gulf of California, Mexico, were examined for cestodes. Four new species, Rhinebothrium chollaensis n. sp., Rhinebothrium gravidum n. sp., Eutetrarhynchus cortezensis n. sp., and Prochristianella minima n. sp., are described. This is the first record of these 3 genera in the Gulf of...

  19. Benchmarking of a bidimensional flood analysis with a structural measure in the catchment Rosarito Huahuatay Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Faustino De Luna C.

    2016-01-01

    Not necessarily, the works are constructed to reduce flood damages. Sometimes the water that temporarily occupied an area of land can be shifted to other areas where it could cause further injury; it is therefore advisable to make comprehensive basin-wide studies to evaluate the goodness of the proposed works, usually with simulation models embracing the basin where the floodplains are located…

  20. [Asteroidea, Echinoidea y Holothuroidea in shallow bottoms of Bahía de Loreto, Baja California Sur, Mexico].

    Science.gov (United States)

    Holguin Quiñones, O; Wright López, H; Solís Marín, F

    2000-12-01

    To evaluate echinoderm distribution, abundance and density a double 50 m transect, with a side observation range of 2.5 m was used at each of 11 stations (bimonthly samplings, Aug. 1997-Febr. 1998). In Bahía de Loreto the Phylum Echinodermata consists of 26 taxa. The greatest mean abundance by transect and mean densities in order of importance for Echinoidea were: Echinometra vanbrunti (94.1 +/- 52.9 ind, 0.25 ind/m2), Centrostephanus coronatus (38.15 +/- 9.15 ind, 0.06 ind/m2), Tripneustes depressus (28.68 +/- 6.86 ind, 0.039 ind/m2), Eucidaris thouarsii (10.66 +/- 3.37 ind, 0.025 ind/m2) and Diadema mexicanum (11.75 +/- 4.92 ind, 0.023 ind/m2); for Asteroidea were: Phataria unifascialis, Mithrodia bradleyi and Acanthaster planci. Asteroidea was the dominant class with 12 species, followed by Echinoidea with ten and Holothuroidea was represented by four species.

  1. Dinámica del plancton en la región sur de la Corriente de California

    Directory of Open Access Journals (Sweden)

    Sergio Hernández Trujillo

    2001-03-01

    Full Text Available Se efectuó el análisis de la abundancia de la biomasa zooplanctónica, del micro y nanofitoplancton y de Calanus pacificus Brodsky 1948 en combinación con datos de temperatura superficial del mar en la costa occidental de la península de Baja California, entre febrero de 1983 y septiembre de 1991. La biomasa del zooplancton presentó una tendencia estacional de variación de la abundancia. Respecto al fitoplancton, la abundancia mensual de la fracción nanofitoplancton (We analyzed zooplankton biomass, micro- and nannophytoplankton abundance, Calanus pacificus Brodsky 1948 abundance, and sea surface temperature along the west coast of Baja California between February 1983 and September 1991. The zooplankton biovolume abundance decreased from spring to autumn. The average abundance of nannophytoplankton (< 20µm was generally higher than microphytoplankton (20 µm. Both increased 3.5 times in abundance after 1986. Seasonally, both fractions (NP and MP were least abundant in winter and most abundant in summer and autumn. Calanus pacificus abundance was variable, but especially high in May of some years. Abundance was lowest in winter and highest in spring, dropping in summer and autumn. Sea surface temperatures averaged 21.5 ºC, with highest in autumn (24.2ºC and the lowest in spring (17.9ºC. C. pacificus abundance and sea surface temperature were inversely related by cruise, season, and latitude. The phytoplankton abundance and zooplankton biomass and C. pacificus abundance showed low and high abundance patterns coincident with warming and cooling events (El Niño-La Niña.

  2. Organchlorine content and shell thickness in brown booby (Sula leucogaster) eggs in the Gulf of California and the southern Pacific coast of Mexico.

    Science.gov (United States)

    Mellink, Eric; Riojas-López, Mónica E; Luévano-Esparza, Jaime

    2009-07-01

    We determined egg concentrations of organochlorines and thickness of eggshells from brown boobies at eight colonies ranging from the northern Gulf of California to southern Mexico. The only common residue was that of DDE, which was found in almost all eggs. DDE content apparently reflected pre-1990 DDT use in nearby agricultural areas and, at one site, intensive mosquito control for high-end tourism development. There were no inter-colony differences in eggshell thickness, and variation in this variable likely reflected individual bird characteristics and/or individual feeding source. This variable was not a good proxy to DDE exposure of brown boobies, under current DDE levels in the brown booby trophic chain. In the northern Gulf of California, eggshell thickness has recovered to pre-DDT conditions. Our data indicate that the Gulf of California and southwestern coast of Mexico have a healthy near-shore marine environment, as far as organochlorines are concerned.

  3. [Taxonomic composition and zoogeographical aspects of deep sea fishes (90-540m) from the Gulf of California, Mexico].

    Science.gov (United States)

    López-Martínez, Juana; Acevedo-Cervantes, Alejandro; Herrera-Valdivia, Eloisa; Rodríguez-Romero, Jesús; Palacios-Salgado, Deivis S

    2012-03-01

    The Gulf of California has a high variety of ecosystems that allow different services and the fishery resources play a prominent role in its ecology, evolution and economics. Fish coastal species have been previously reported for most coastal areas, especially those species that are subject to fishing, however, little is known on the species from deep sea zones, due to sampling difficulties. We studied the deep sea fishes collected with trawl nets during three research surveys in the Gulf of California, Mexico in 2004-2005. We provide a systematic checklist and some notes on biogeographical aspects. For this, 74 fishing hauls were done, and a total of 9 898 fishes were captured, belonging to two classes, 15 orders, 35 families, 53 genera and 70 species. The best represented families in number of species were: Paralichthyidae (eight), Serranidae (six), and Scorpaenidae and Triglidae with five species each one. The typical families from deep waters were: Ophidiidae, Moridae, Lophiidae, Scorpaenidae, Triglidae, Paralichthydae, Pleuronectidae and Cynoglossidae. Size range varied from 13cm for the Splinose searobin (Bellator xenisma) to 234cm in the Pacific Cutlassfish (Trichiurus nitens). The biogeographical affinity showed that species with affinity to the East Tropical Pacific (ETP) dominated, followed by species from San Diego-Panamic, San Diego-Panamic-Peruvian-Chilean and Oregonian-Cortes provinces, respectively. A biogeographic overlap was found in the fauna, which reflects the Gulf of California's geographical position, with distribution limits of species from temperate, tropical and warm-temperature transition affinities, divisions that characterize the Gulf of California. Taxonomic status of fish with a focus on composition, location, characterization and zoogeography are fundamental to any subject of biodiversity and fisheries management actions.

  4. Bimodal Distribution of Risk for Childhood Obesity in Urban Baja California, Mexico

    OpenAIRE

    Wojcicki, Janet M.; Jimenez-Cruz, Arturo; Bacardi-Gascon, Montserrat; Schwartz, Norah; Heyman, Melvin B.

    2012-01-01

    In Mexico, higher socioeconomic status (SES) has been found to be associated with increased risk for obesity in children. Within developed urban areas, however, there may be increased risk among lower SES children. Students in grades 4–6 from five public schools in Tijuana and Tecate, Mexico, were interviewed and weight, height and waist circumference (WC) measurements were taken. Interviews consisted of questions on food frequency, food insecurity, acculturation, physical activity and lifest...

  5. Mexico.

    Science.gov (United States)

    1988-02-01

    Focus in this discussion of Mexico is on the following: geography; the people; history; political conditions; the economy; foreign relations; and relations between the US and Mexico. As of July 1987, the population of Mexico numbered 81.9 million with an estimated annual growth rate of 2.09%. 60% of the population is Indian-Spanish (mestizo), 30% American Indian, 9% white, and 1% other. Mexico is the most populous Spanish-speaking country in the world and the 2nd most populous country in Latin America. Education is decentralized and expanded. Mexico's topography ranges from low desert plains and jungle-like coastal strips to high plateaus and rugged mountains. Hernan Cortes conquered Mexico in 1919-21 and founded a Spanish colony that lasted for almost 300 years. Independence from Spain was proclaimed by Father Miguel Hidalgo on September 16, 1810; the republic was established on December 6, 1822. Mexico's constitution of 1917 provides for a federal republic with a separation of powers into independent executive, legislative, and judicial branches of government. Significant political themes of the administration of President Miguel de la Madrid Hurtado, who began his 6-year term in 1982, have been restructuring the economy, liberalizing trade practices, decentralizing government services, and eliminating corruption among public servants. In 1987, estimates put the real growth of the Mexican economy at 1.5%; the gross domestic product (GDP) had shrunk by 3.5% in 1986. Yet, on the positive side, Mexico's international reserves increased to record levels in 1987 (to about $15 billion), and its current account surplus reached more than $3 billion. Mexico has made considerable progress in moving to restructure its economy. It has substantially reduced impediments to international trade and has moved to reduce the number of parastatal firms. 1987 was the 2nd consecutive year in which Mexico recorded triple-digit inflation; inflation reached 158.8%. Other problems include

  6. New state records and updated checklist of Aphodiini and Eupariini (Coleoptera: Scarabaeidae: Aphodiinae) from Mexico.

    Science.gov (United States)

    Minor, Pablo

    2017-03-22

    Thirty one new state records of species of Aphodiinae (Coleoptera: Scarabaeidae) from Mexico are presented, 24 species belong to Aphodiini and seven species to Eupariini into the genera Agrilinellus, Alloblackburneus, Aphotaenius, Ataenius, Blackburneus, Cephalocyclus, Coelotrachelus, Euparia, Euparixia, Geomyphilus, Gonaphodiellus, Gonaphodiopsis, Haroldiellus, Liothorax, Nialaphodius, Odontolytes, Oscarinus, Pharaphodius, and Planolinellus. New records are from the states of Aguascalientes, Baja California, Baja California Sur, Campeche, Colima, Chiapas, Estado de México, Guerrero, Hidalgo, Jalisco, Michoacán, Morelos, Nayarit, Puebla, Sonora, Tabasco, Tamaulipas, Tlaxcala, Veracruz, Zacatecas, and Distrito Federal. A checklist with updated nomenclature is included for the recorded species of Aphodiini and Eupariini from Mexico.

  7. Estructura de tallas y edad del marlin rayado Tetrapturus audax (Pisces:Xiphidae,en Cabo San Lucas,Baja California Sur,México

    Directory of Open Access Journals (Sweden)

    Felipe Neri Melo Barrera

    2004-12-01

    Full Text Available De 1988 a 1993 se muestrearon 1030 ejemplares de marlin rayado (Tetrapturus audax capturados por la flota deportiva de Cabo San Lucas.Se recolectaron 389 espinas dorsales para la estimación de la edad.La relación Longitud mandibular-Radio total de la espina es similar para hembras y machos.Se encontró que la cuarta espina dorsal refleja adecuadamente el crecimiento.La periodicidad de formación de las marcas de crecimiento es anual y parece que se relaciona con la temperatura superficial promedio del mar.Se contaron las bandas opaco-hialinas en cada corte de las espinas,y se encontraron diez grupos de edad (del dos al once,siendo el grupo siete el más abundante, seguido por los grupos seis y ocho.Las tallas observadas para el marlin rayado fueron de 160-280 cm de longitud mandibular,el 90%de los organismos estuvieron entre 190 y 225 cm.Los ejemplares pequeños se incorporan a la pesquería de junio hasta diciembre.Size and age structure of the striped marlin Tetrapturus audax (Pisces:Xiphidae,at Cabo San Lucas,Baja California Sur,México .The striped marlin (Tetrapturus audaxis found in temperate and tropical waters of the Pacific and Indian Ocean.It is particularly abundant in the southern tip of the Baja California peninsula.Specimens brought to Cabo San Lucas port (22 °53 ’ N y 109 °54 ’ Wby the sport fishery fleet that operates withing a radius of 54 km from 1988 to 1993 were sexes,measured and weighed.A total 1030 individuals were sampled.Dorsal fin spines (389were collected for age estimation.The spines were sectioned and hyaline-opaque bands counted.The relation of length to spine radius was similar for males and females.The fourth dorsal spine reflected the growth of the fish.The rhythm of growth mark formation is yearly and related to the sea surface temperature.Ten age groups were found and the seventh group was the most abundant,followed by groups "6 "and "8 ".The age structure of the striped marlin was stable in the study

  8. La fotografía de Julius Shulman y la construcción de la imagen de la arquitectura del sur de California

    Directory of Open Access Journals (Sweden)

    Daniel Díez Martínez

    2014-10-01

    Full Text Available A Julius Shulman le correspondió, casi en exclusiva, la labor de cronista gráfico de la arquitectura moderna en el sur de California. Consciente de la dificultad de hacer ver al público la belleza de estas construcciones, Shulman desarrolló un lenguaje propio con un marcado sentido escenográfico, un encuentro entre la fotografía arquitectónica clásica y la publicidad contemporánea inspirada en la cultura pop en la que la colocación de los muebles en intervalos estratégicos, la iluminación, la elección y actitud de los modelos o la vegetación estaban cuidadosamente estudiados para guiar la vista del espectador hacia la arquitectura y el estilo de vida que de esta se desprendía. El artículo propone una visión transversal de la fotografía de Shulman y establece lazos entre su obra y la tensión política que se respiraba en los Estados Unidos de la Guerra Fría. Gracias a las “escenas” capturadas en sus fotografías, la arquitec­tura moderna californiana quedaría por siempre asociada al contexto creado por el fotógrafo, dando lugar a imágenes que el tiempo ha elevado a la categoría de iconos culturales del siglo XX. Como la arquitectura que retrataba, la fotografía se convirtió en una exaltación de la modernidad entendida como una nueva era de bienestar, prosperidad y progreso.

  9. Macroalgas submareales de la bahía de Todos Santos, Baja California, México Submareal macroalgae of the Todos Santos Bay, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    Raúl Aguilar-Rosas

    2010-12-01

    Full Text Available Con el fin de identificar y caracterizar la composición de especies de la zona submareal de la bahía de Todos Santos, Baja California, México; se realizaron muestreos de macroalgas marinas bentónicas en 7 sitios durante 1995-2000. Como resultado de 25 buceos Scuba entre 3 y 33 m de profundidad se encontraron 150 especies de macroalgas para el área de estudio; 10 son Chlorophyta, 26 Phaeophyta y 114 Rhodophyta. Del total, 47 son registros nuevos para el área de estudio y 2 de éstos, Faucheocolax attenuata Setchell y Minium parvum R.L. Moe, son nuevos para la flora marina del Pacífico de México. Se incluye una revisión de las investigaciones en las que se han considerado las macroalgas presentes en la bahía de Todos Santos y una discusión sobre la composición de las especies encontradas, su distribución vertical y reproducción, así como sobre las especies epífitas y parásitas del área.In order to identify and characterize the species composition of the subtidal zone of the Todos Santos Bay, Baja California, Mexico, benthic marine macroalgae were sampled at 7 sites from 1995 to 2000. As a result of 25 scuba at derds for the study area, of which Faucheocolax attenuata Setchell and R.L Moe Minium parvum are new to the marine flora of Pacific Mexico. We include a research that consider the macroalpths between 3 and 33 m we found a total of 150 species of macroalgae for the study area, of which 10 are Chlorophyta, 26 Phaeophyta and 114 Rhodophyta; 47 species represent new recogae in the Todos Santos Bay and a discussion on the composition of species found, its vertical distribution and reproduction, particularly the species epiphytes and parasites present in the study area.

  10. Drug-scene familiarity and exposure to gang violence among residents in a rural farming community in Baja California, Mexico

    Science.gov (United States)

    Volkmann, Tyson; Fraga, Miguel A.; Brodine, Stephanie K.; Iñiguez-Stevens, Esmeralda; Cepeda, Alice; Elder, John P.; Garfein, Richard S.

    2012-01-01

    We examined drug-scene familiarity and exposure to gang violence among residents of a migrant farming community in rural Baja California, Mexico. In October 2010, 164 members of a single colonia (community) underwent an interviewer-administered survey to assess ‘exposure to gang violence’ and ‘drug-scene familiarity’, as well as other health indicators. Logistic regression was used to identify correlates of exposure to gang violence. Overall, 20% of participants were male, the median age was 27 years, 24% spoke an indigenous language, 42% reported exposure to gang violence, and 39% reported drug-scene familiarity. Factors independently associated with exposure to gang violence included being younger (AOR=0.80 per 5-year increase, 95% CI=0.67–0.96), living in the community longer (AOR=1.47 per 5-year increase, 95% CI=1.11–1.72), higher educational attainment (AOR=1.70 per 5-year increase, 95% CI=1.07–1.12), and drug-scene familiarity (AOR=5.10, 95%CI=2.39–10.89). Exposure to gang violence was very common in this community and was associated with drug-scene familiarity, suggesting a close relationship between drugs and gang violence in this rural community. In a region characterised by mass migration from poorer parts of Mexico, where drugs and gangs have not been previously reported, emerging social harms may affect these communities unless interventions are implemented. PMID:23072623

  11. New records of the deep-sea anemone Phelliactis callicyclus Riemann-Zurneck, 1973 (Cnidaria, Actiniaria, Hormathiidae) from the Gulf of California, Mexico.

    Science.gov (United States)

    Hendrickx, M E; Hinojosa-Corona, A; Ayón-Parente, M

    2016-10-20

    Specimens of a deep-sea anemone were observed in photographs and video footage taken with the Remotely Operated Vehicle JASON (WHOI Deep Submergence Laboratory) in the Gulf of California, Mexico, in May 2008. Comparison of our material with photographs and description of this species available in literature indicate that the sea anemones filmed during the JASON survey are most likely to represent Phelliactis callicyclus Riemann-Zurneck, 1973. This species has previously been reported from a locality in the Gulf of California near the present record. During the JASON survey, 28 specimens of P. callicyclus were spotted in 27 locations during six dives. The specimens occurred on angular rock outcrops along the escarpments of the transform faults of the Gulf of California, between depths of 993-2543 m and at temperatures ranging from 2.3 to 4.5°C. Based on these new records, Phelliactis callicyclus appears to be widely spread in the Gulf of California.

  12. 20-Hz pulses and other vocalizations of fin whales, Balaenoptera physalus, in the Gulf of California, Mexico.

    Science.gov (United States)

    Thompson, P O; Findley, L T; Vidal, O

    1992-12-01

    Low-frequency vocalizations were recorded from fin whales, Balaenoptera physalus, in the Gulf of California, Mexico, during three cruises. In March 1985, recorded 20-Hz pulses were in sequences of regular 9-s interpulse intervals. In August 1987, nearly all were in sequences of doublets with alternating 5- and 18-s interpulse intervals. No 20-Hz pulse sequences of any kind were detected in February 1987. The typical pulse modulated from 42 to 20 Hz and its median duration was 0.7 s (1985 data). Most other fin whale sounds were also short tonal pulses averaging 82, 56, and 68 Hz, respectively, for the three cruises; 89% were modulated in frequency, mostly downward. Compared to Atlantic and Pacific Ocean regions, Gulf of California 20-Hz pulses were unique in terms of frequency modulation, interpulse sound levels, and temporal patterns. Fin whales in the Gulf may represent a regional stock revealed by their sound characteristics, a phenomenon previously shown for humpback whales, birds, and fish. Regional differences in fin whale sounds were found in comparisons of Atlantic and Pacific locations.

  13. Mercury poisoning associated with beauty cream--Texas, New Mexico, and California, 1995-1996.

    Science.gov (United States)

    1996-05-17

    The Texas Department of Health (TDH), New Mexico Department of Health (NMDH), and San Diego County Health Department (SDCHD) recently investigated three cases of mercury poisoning among persons who had used a beauty cream produced in Mexico. The investigations implicated the beauty cream as the source of the mercury. The cream, marketed as "Crema de Belleza--Manning," lists "calomel" (mercurous chloride) as an ingredient and was found to contain 6%-8% mercury by weight. This report summarizes the ongoing investigation of these and other possible cases.

  14. A new species of pine anole from the Sierra Madre del Sur in Oaxaca, Mexico (Reptilia, Squamata, Dactyloidae: Anolis).

    Science.gov (United States)

    Köhler, Gunther; Pérez, Raúl Gómez Trejo; Petersen, Claus Bo P; de La Cruz, Fausto R Mendez

    2014-01-09

    We describe the new species Anolis peucephilus sp. nov. from the Pacific versant of southern Mexico. Anolis peucephilus differs from all congeners by having a combination of (1) smooth ventral scales; (2) usually a patch of three greatly enlarged supraocular scales; (3) extremely short hind legs, longest toe of adpressed hind leg reaching to a point between levels of axilla and ear opening, ratio shank length/snout-vent length 0.18-0.21; (4) circumnasal usually in contact with first supralabial; and (5) a large yellowish orange dewlap in males and a very small to small white dewlap in females. In external morphology, A. peucephilus is most similar to A. omiltemanus from which it differs by having even shorter hind legs with the longest toe of adpressed hind leg reaching to a point between levels of axilla and ear opening (versus usually to ear opening, occasionally to slightly beyond ear opening or to a point between shoulder and ear opening in A. omiltemanus), a slightly larger dewlap in females, to 64 mm2 (versus to 41 mm2 in A. omiltemanus), the circumnasal usually in contact with the first supralabial (versus those scales separated by the presence of a subnasal in A. omiltemanus), and 4-6 internasal scales in the new species (versus usually 6-7 in A. omiltemanus). Furthermore, A. peucephilus differs from A. omiltemanus in hemipenial morphology (no finger-like processus on asulcate side in A. peucephilus versus such a processus present in A. omiltemanus). Also, in a preliminary molecular genetic analysis of the mitochondrial CO1 gene fragment, A. peucephilus has a genetic distance of 11.5% from A. omiltemanus. Anolis peucephilus was collected at night while the lizards were sleeping in pine trees, 2-10 m above the ground.

  15. Estructura de la avifauna durante el periodo invierno-primavera en el Estero Rancho Bueno, Baja California Sur, México Structure of the avifauna during the winter-spring season in Estero Rancho Bueno, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Edgar Amador

    2006-12-01

    Full Text Available Mensualmente, de noviembre de 1993 a junio de 1994, se contaron las aves en un ambiente de manglar en Estero Rancho Bueno de la costa occidental de Baja California Sur. Sumaron en total 5965 aves de 56 especies de 10 órdenes y 21 familias. La estacionalidad estuvo definida por 31 residentes, 22 migratorias y tres indeterminadas. La mayoría de las especies se consideran costeras y/o estuarinas; sin embargo, hay algunas terrestres. Existen indicios de que por lo menos 2 especies se reproducen en el área, 4 presentan alguna categoría en la normatividad y 5 se utilizan comercialmente. La comunidad de aves es más diversa a principios de invierno y disminuye hacia finales de primavera, coincidiendo con la menor riqueza de especies y el aumento en la dominancia del pelícano café (Pelecanus occidentalis, gaviota occidental (Larus occidentalis y gaviota pico anillado (Larus delawarensis. El análisis para las áreas con manglar y sin manglar indicó que el número total de individuos (N, el número de individuos de la especie más abundante (Nmax y la riqueza de especies (S son mayores en el hábitat de áreas abiertas, mientras que la equidad (E siempre fue mayor en el hábitat de manglar.Periodic surveys were conducted from November 1993 to June 1994 in Estero Rancho Bueno, a mangrove lagoon environment on the west coast of Baja California Sur. We found 5,65 birds (56 species. The avifauna included 31 resident, 22 migratory, and 3 species of undeterminated migratory status. Most of the species were coastal and estuarine birds; however there were some terrestial and wide-ranging birds. There is evidence that at least 2 species breed in the area; 4 species are protected by Mexican law and 5 species have commercial value. Different indices show that the bird community diversity is lower by the end of spring and the dominance of the Brown Pelican (Pelecanus occidentalis, the Western Gull (Larus occidentalis, and the Ring-billed Gull (L. delawarensis

  16. 75 FR 68681 - Pistachios Grown in California, Arizona, and New Mexico; Modification of the Aflatoxin Regulations

    Science.gov (United States)

    2010-11-09

    ... New Mexico; Modification of the Aflatoxin Regulations AGENCY: Agricultural Marketing Service, USDA... adopting, as a final rule, without change, an interim rule that modified the aflatoxin sampling and testing... interim rule streamlined the aflatoxin sampling and testing procedures under the order's rules and...

  17. Ads & Arts & Architecture : la publicidad en la revista "Arts & Architecture" en la construcción de la imagen de las arquitecturas del sur de California (1938-1967)

    OpenAIRE

    Díez Martínez, Daniel

    2016-01-01

    Esta tesis aborda el análisis del proceso de construcción de la imagen de las arquitecturas del sur de California desde el estudio de una fuente documental poco habitual: la publicidad que apareció en los números de la revista Arts & Architecture entre 1938 y 1967. En esos años la ciudad de Los Ángeles intentaba dar respuesta a una acuciante falta de vivienda, que se venía viviendo desde antes de la Gran Depresión, pero que se acrecentó significativamente tras la explosión demográfica surgida...

  18. Herpetofauna associated with palm oases across the Californian-Sonoran transition in northern Baja California, Mexico

    Science.gov (United States)

    Hart Welsh; W. H. Clark; E. Franco-Vizcaíno; J. H. Valdéz-Villavicencio

    2010-01-01

    Ecological boundaries have been of interest to naturalists since the time of Darwin and Wallace because they are transitional zones on the landscape across which distinct changes occur in constitution of plant and animal communities. In the xeric landscapes of the central Baja California Peninsula, fan palm (Erythea armata and ...

  19. Deep-water Asteroidea (Echinodermata collected during the TALUD cruises in the Gulf of California, Mexico Asteroidea (Echinodermata de aguas profundas recolectados durante cruceros TALUD en el Golfo de California, México

    Directory of Open Access Journals (Sweden)

    Michel E. Hendrickx

    2011-09-01

    Full Text Available During a series of cruises aboard the R/V "El Puma" aimed at collecting the deep-water benthic and pelagic fauna off the Pacific coast of Mexico, in the eastern Pacific, samples of Asteroidea were collected below 500 m depth (587-1 526 m. A total of 335 specimens were collected, belonging to 18 species, 14 identified to species, 3 to genus, and 1 previously undescribed species. New records are provided for Dipsacaster laetmophilus Fisher, 1910, Myxoderma sacculatum (Fisher, 1905, Peribolaster biserialis Fisher, 1905, Ampheraster chiroplus Fisher, 1928, Ampheraster hyperoncus (H. L. Clark, 1913, Anteliaster coscinactis Fisher, 1923, Nearchaster aciculosus (Fisher, 1910, Ceramaster leptoceramus (Fisher, 1905, Mediaster transfuga Ludwig, 1905, and Lophaster furcilliger Fisher, 1905. All species were collected below the oxygen minimum zone that extends throughout the central and southern Gulf of California, or within the threshold zone where severe to mild hypoxic conditions prevail. Epibenthic dissolved oxygen concentrations associated with the capture of the specimens show support for strong tolerance to severe hypoxia (Durante una serie de campañas oceanográficas realizadas a bordo del B/O "El Puma", enfocadas a la recolección de la fauna bentónica y pelágica de aguas profundas en la costa del Pacífico de México, en el Pacífico oriental, se recolectaron ejemplares de Asteroidea por debajo de 500 m de profundidad (587-1 526 m. Un total de 335 ejemplares fueron recolectados, pertenecientes a 18 especies; 14 fueron determinadas hasta especie, 3 hasta género y 1 especie no descrita. Se proporcionan nuevos registros para Dipsacaster laetmophilus Fisher, 1910, Myxoderma sacculatum (Fisher, 1905, Peribolaster biserialis Fisher, 1905, Ampheraster chiroplus Fisher, 1928, Ampheraster hyperoncus (H. L. Clark, 1913, Anteliaster coscinactis Fisher, 1923, Nearchaster aciculosus (Fisher, 1910, Ceramaster leptoceramus (Fisher, 1905, Mediaster transfuga

  20. Dimorfismo sexual de Aspidoscelis costata costata (Squamata: Teiidae en el sur del Estado de México, México Sexual dimorphism of Aspidoscelis costata costata (Squamata: Teiidae in the south of the State of Mexico, Mexico

    Directory of Open Access Journals (Sweden)

    MAGDALENA AGUILAR-MORENO

    2010-12-01

    Full Text Available El dimorfismo sexual es una característica extendida en lacertilios y se relaciona con la adecuación de los individuos. En este estudio se analizó si Aspidoscelis costata costata (Squamata presenta dimorfismo sexual al sur del Estado de México, México, especialmente en relación a su forma corporal altamente conservada dentro de la familia Teiidae. La población estudiada habita a 1500 msnm. Se utilizaron individuos adultos que fueron capturados y liberados durante estudios ecológicos. Para cada individuo se registró la longitud hocico-cloaca, el peso corporal, largo de la cabeza, ancho de la cabeza, alto de la cabeza, longitud del fémur y distancia interaxilar. Los análisis realizados indicaron que los machos fueron más grandes en longitud hocico-cloaca y peso; además presentaron dimensiones más grandes en cabeza y fémur que hembras de la misma longitud hocico-cloaca. La distancia interaxilar fue mayor en hembras que en machos de la misma longitud hocico-cloaca. El dimorfismo sexual de A. costata costata puede explicarse por selección sexual y selección por fecundidad.Sexual dimorphism is a widespread characteristic in lizards, and it has been related to the individual fitness. Sexual dimorphism was investigated in Aspidoscelis costata costata (Squamata to the south of the State of Mexico, Mexico, relating to its body proportions highly similar within the Teiidae. Study area was located at 1500 m. Adult individuals from mark-recapture study were used. Morphometric characteristics were measured in individuals of A. costata costata: snout-vent length, mass, head length, head width, head height, femur length and interlimb length. Males were larger than females for SVL and mass. At the same body, males had longer heads and femur and shorter interlimb length than did conspecific females. The sexual dimorphism of A. costata costata can be explained by selection sexual selection and fecundity selection.

  1. Characterization of Fog Water Collection Potential and Quality on California State University Monterey Bay and Glen Deven Ranch Near Big Sur

    Science.gov (United States)

    Ruiz, G. E.

    2005-12-01

    Since June 25, 2005 I have had three standard fog collectors (SFCs) in place at various locales throughout the Greater Monterey Area. From June 25 until July 22, the three SFCs were all located on the California State University Monterey Bay (CSUMB) campus, only a few meters above sea level. Their orientations were all due west. On July 22 two of the SFCs were relocated to a hilly coastal location in Big Sur several hundred meters above sea level known as Glen Deven Ranch. They will remain there until October 15. An SFC is a device that collects fog water from the air. They each consist of a 1 m2 copper frame with a mesh net wound around it. This frame is affixed to two steel posts and is 2 m off the ground. Below the frame sits a trough that has a bottom slanted so that all water in it flows towards a spout at one end. This spout is connected by a tube to a container or data logging rain gauge. Preliminary data analysis shows that maximal collection occurs in the early morning hours at CSUMB and during the evening at Glen Deven Ranch. The weekly volumes of water collected at Glen Deven thus far have been between 2 and 30 times the volume collected on CSUMB. During the time period of operation, the SFCs connected to containers collected 114.37 L in total. The maximum collected for one week is 6.75 L on campus and 19.21 L at the ranch. The data logged by the rain gauge is currently being analyzed to determine how much water has been collected by the SFC it has been connected to. Water from the Glen Deven SFCs and from the CSUMB SFC has been sent to the Santa Clara Municipal Water District where the purity and potability of the water are being investigated. Initially, I wanted to determine about how much water could be obtained in this fashion for use in the Monterey Bay Area. I assumed my results would be broadly applicable, but due to the high variability of fog collection rates I observed even in collectors only a couple hundred of meters apart, any conclusions I

  2. Distribución de aves acuáticas y rapaces en un embalse dulceacuícola artificial de Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    José Alfredo Castillo-Guerrero

    2001-12-01

    Full Text Available Se determinó la composición taxonómica y la distribución espaciotemporal de aves acuáticas en el estanque de almacenamiento del ejido El Centenario, B.C.S., durante 24 censos quincenales (abril de 1998 a marzo de 1999. El estanque es particularmente atractivo para las aves por la variedad de alimento que ofrece. Se realizaron 25 563 registros de 69, entre las que se reporta por primera vez en la región a Chlidonias niger y Phalaropus tricolor. La riqueza y la abundancia fueron determinadas por el componente migratorio, principalmente anátidos (16 especies y 55.6 % del total observado, respectivamente y aves playeras (18 especies y 13.3 %. La zona que presentó el número mayor de especies e individuos fue la C, la más profunda y heterogénea. La especie más importante fue Oxyura jamaicensis (30 % del total observado, con los números más altos en la península. Este sitio presentó un componente aviar propio atípico, dada la aridez de la región, y funcionó como un sitio de escala e invernación para especies migratorias. Su componente incluye aves de afinidades costeras y dulceacuícolas, lo que se refleja en sus altas riquezas, contribuyendo notablemente a la biodiversidad localWe determined the taxonomic composition and spatial-temporal distribution of aquatic and raptor birds in a freshwater artificial pond of El Centenario, Baja California Sur, México, during 24 biweekly censuses (April, 1998 to March, 1999. The pond is particularly attractive for birds because of its variety of food items. A total 25 563 records of 69 species were done, among them the first report of Chlidonias niger and Phalaropus tricolor for the region. Species richness and abundance were determined for the migrant component, mostly Anatidae (16 species and 55.6 % of the total abundance and shorebirds (18 species and 13.3%. The greater number of species and individuals was in C the deepest and more heterogeneus section of the pond. The most important

  3. Caracterización del peligro por inundaciones en el oasis La Purísima, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Jobst Wurl

    2015-01-01

    Full Text Available En el estado de Baja California Sur existen solo cuatro oasis con extensiones mayores a 2.0 km2; La Purísima (2.25 km2 representa el tercero en extensión. En el pasado el oasis fue frecuentemente afectado por inundaciones resultantes de los eventos extremos de precipitación, que generaron graves daños en la cuenca. Se realizó un diagnóstico del oasis La Purísima, con respecto a posibles inundaciones como consecuencia de lluvias extremas, lo cual incluye el análisis estadístico de la precipitación para la elaboración de un modelo hidrológico e hidráulico, con el fin de calcular el caudal máximo, el volumen y la frecuencia de crecidas en los cursos del arroyo Cadegomo bajo diferentes escenarios de lluvias extremas. Finalmente se elaboró un mapa de peligro por inundación según los escenarios elaborados. Se efectuó un análisis de la ocurrencia de inundaciones en el pasado y sus efectos en el oasis por medio de evidencias históricas de inundación de la zona, para verificar su posible aplicación en la calibración de los modelos. Los caudales resultantes de los eventos de precipitación extremos generan un incremento importante de los niveles en el drenaje de la cuenca. La respuesta del arroyo es un incremento en el área de inundación de hasta 14% respecto al tiempo de retorno de 20 años. Un evento de 1 000 años generaría un incremento en el área de inundación de 67% y bajas, afectando las zonas de la región urbana, así como todos los lotes de cultivo.

  4. Dynamic of aragonite saturation horizon in waters of Baja California, Mexico

    Science.gov (United States)

    Valencia Gasti, J. A.; Oliva, N. L.; Martin Hernandez-Ayon, J. M.; Durazo, R.; Santamaria-del-Angel, E.; Alin, S. R.; Feely, R. A.

    2016-02-01

    The status of the ocean acidification can be estimated by hydrographic calibrated data with carbon system variables. Recently empirical models for the coast of southern California and northern Baja California were developed. These models can be applied mainly in places where hydrographic data exist but also with measurements of the carbon system available for calibrations. The aim of this study was to analyze the hydrographic data of a transect in front of Ensenada's coast, corresponding to the line 100 of IMECOCAL's program during the period 1998-2014. Such data was used to apply an empirical model to estimate the aragonite saturation state (Ωa) in order to identify oceanographic conditions that could influence the variability of the depth of saturation horizon that might be in the last 17 years in habitats of shellfish and oyster production areas adjacent to the coast of Ensenada. It was found that the temperature, salinity, oxygen, pH, dissolved inorganic carbon and Ωa showed a seasonal variation with different oceanographic scenarios: (a) during spring-summer the California Current flow to the Ecuador and upwelling events are presented; (b) in autumn-winter the influence the Southern California Bight Eddy can transport water from the subarctic to Ecuador in the oceanic portion of the transect and towards the pole at the coastal side. These oceanographic characteristics encourage that coastal stations present seasonal variability, reflected in the depth of the horizon Ωa shallower ( 66m + 21m) in spring and deeper into the winter ( 122m + 35). It has been reported that the upwelling off the coast of BC transport water from a depth between 80 and 90m in spring and summer; therefore under saturated water (Ωa coast of BC

  5. Seismic Structural Setting of Western Farallon Basin, Southern Gulf of California, Mexico.

    Science.gov (United States)

    Pinero-Lajas, D.; Gonzalez-Fernandez, A.; Lopez-Martinez, M.; Lonsdale, P.

    2007-05-01

    Data from a number of high resolution 2D multichannel seismic (MCS) lines were used to investigate the structure and stratigraphy of the western Farallon basin in the southern Gulf of California. A Generator-Injector air gun provided a clean seismic source shooting each 12 s at a velocity of 6 kts. Each signal was recorded during 6- 8 s, at a sampling interval of 1 ms, by a 600 m long digital streamer with 48 channels and a spacing of 12.5 m. The MCS system was installed aboard CICESE's (Centro de Investigacion Cientifica y de Educacion Superior de Ensenada) 28 m research vessel Francisco de Ulloa. MCS data were conventionally processed, to obtain post- stack time-migrated seismic sections. The MCS seismic sections show a very detailed image of the sub-bottom structure up to 2-3 s two-way travel time (aprox. 2 km). We present detailed images of faulting based on the high resolution and quality of these data. Our results show distributed faulting with many active and inactive faults. Our study also constrains the depth to basement near the southern Baja California eastern coast. The acoustic basement appears as a continuous feature in the western part of the study area and can be correlated with some granite outcrops located in the southern Gulf of California islands. To the East, near the center of the Farallon basin, the acoustic basement changes, it is more discontinuous, and the seismic sections show a number of diffracted waves.

  6. New geographic and depth records for deep-water mollusks in the Gulf of California, Mexico Nuevos registros geográficos y batimétricos para moluscos de mar profundo en el golfo de California, México

    Directory of Open Access Journals (Sweden)

    Pablo Zamorano

    2007-12-01

    Full Text Available Six oceanographic cruises (Talud IV-IX were made in the southern Gulf of California aboard the R/V El Puma of the Universidad Nacional Autónoma de México. A total of 56 species of deep-sea mollusks were identified, of which 16 (13 Bivalvia, 2 Gastropoda, 1 Scaphopoda represent either a new geographic or bathymetric record, or both.A partir de 6 campañas oceanográficas (Talud IV-IX realizadas en el sur del golfo de California a bordo del B/O "El Puma" de la Universidad Nacional Autónoma de México, se identificaron 56 especies de moluscos de aguas profundas. De ellas 16 (13 Bivalvia, 2 Gastropoda, 1 Scaphopoda corresponden a un nuevo registro geográfico, batimétrico o ambos.

  7. Organchlorine content and shell thickness in brown booby (Sula leucogaster) eggs in the Gulf of California and the southern Pacific coast of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Mellink, Eric, E-mail: emellink@cicese.m [Departamento de Biologia de la Conservacion, Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, B.C. Carretera Tijuana-Ensenada Km. 107, 22860 Ensenada, B.C. (Mexico); Riojas-Lopez, Monica E., E-mail: meriojas@cucba.udg.m [Departamento de Ecologia, Centro Universitario de Ciencias Biologicas y Agropecuarias, Universidad de Guadalajara, Km. 15.5 Carretera a Nogales, 45100 Zapopan, Jalisco (Mexico); Luevano-Esparza, Jaime, E-mail: jluevano@cicese.m [Departamento de Biologia de la Conservacion, Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, B.C. Carretera Tijuana-Ensenada Km. 107, 22860 Ensenada, B.C. (Mexico)

    2009-07-15

    We determined egg concentrations of organochlorines and thickness of eggshells from brown boobies at eight colonies ranging from the northern Gulf of California to southern Mexico. The only common residue was that of DDE, which was found in almost all eggs. DDE content apparently reflected pre-1990 DDT use in nearby agricultural areas and, at one site, intensive mosquito control for high-end tourism development. There were no inter-colony differences in eggshell thickness, and variation in this variable likely reflected individual bird characteristics and/or individual feeding source. This variable was not a good proxy to DDE exposure of brown boobies, under current DDE levels in the brown booby trophic chain. In the northern Gulf of California, eggshell thickness has recovered to pre-DDT conditions. Our data indicate that the Gulf of California and southwestern coast of Mexico have a healthy near-shore marine environment, as far as organochlorines are concerned. - Wide-range, current picture of organochlorine presence in the environment along the western coast of Mexico.

  8. Candida species diversity and antifungal susceptibility patterns in oral samples of HIV/AIDS patients in Baja California, Mexico.

    Science.gov (United States)

    Clark-Ordóñez, Isadora; Callejas-Negrete, Olga A; Aréchiga-Carvajal, Elva T; Mouriño-Pérez, Rosa R

    2017-04-01

    Candidiasis is the most common opportunistic fungal infection in HIV patients. The aims of this study were to identify the prevalence of carriers of Candida, Candida species diversity, and in vitro susceptibility to antifungal drugs. In 297 HIV/AIDS patients in Baja California, Mexico, Candida strains were identified by molecular methods (PCR-RFLP) from isolates of oral rinses of patients in Tijuana, Mexicali, and Ensenada. 56.3% of patients were colonized or infected with Candida. In Tijuana, there was a significantly higher percentage of carriers (75.5%). Out of the 181 strains that were isolated, 71.8% were Candida albicans and 28.2% were non-albicans species. The most common non-albicans species was Candida tropicalis (12.2%), followed by Candida glabrata (8.3%), Candida parapsilosis (2.2%), Candida krusei (1.7%), and Candida guilliermondii (1.1%). Candida dubliniensis was not isolated. Two associated species were found in 11 patients. In Mexicali and Ensenada, there was a lower proportion of Candida carriers compared to other regions in Mexico and worldwide, however, in Tijuana, a border town with many peculiarities, a higher carrier rate was found. In this population, only a high viral load was associated with oral Candida carriers. Other factors such as gender, use of antiretroviral therapy, CD4+ T-lymphocyte levels, time since diagnosis, and alcohol/ tobacco consumption, were not associated with Candida carriers. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Mediterranean California, Chapter 13

    Science.gov (United States)

    M.E. Fenn; E.B. Allen; L.H. Geiser

    2011-01-01

    The Mediterranean California ecoregion (CEC 1997; Fig 2.2) encompasses the greater Central Valley, Sierra foothills, and central coast ranges of California south to Mexico and is bounded by the Pacific Ocean, Sierra Nevada Mountains and Mojave Desert.

  10. Mexico.

    Science.gov (United States)

    1993-01-01

    The background notes on Mexico provide text and recent statistical information on the geography, population, government, economy, and foreign relations, specifically the North American Free Trade Agreement with US. The 1992 population is estimated at 89 million of which 60% are mestizo (Indian-Spanish), 30% are American Indian, 9% are Caucasian, and 1% are other. 90% are Roman Catholic. There are 8 years of compulsory education. Infant mortality is 30/1000 live births. Life expectancy for males is 68 years and 76 years for females. The labor force is comprised of 30% in services, 24% in agriculture and fishing, 19% in manufacturing, 13% in commerce, 7% in construction, 4% in transportation and communication, and .4% in mining. There are 31 states and a federal district. Gross domestic product (GDP) per capita was $3200 in 1991. Military expenditures were .5% of GDP in 1991. The average inflation rate is 19%. Mexico City with 20 million is the largest urban center in the world. In recent years, the economy has been restructured with market oriented reforms; the result has been a growth of GDP of 3.6% in 1991 from 2% in 1987. Dependence on oil exports has decreased. There has been privatization and deregulation of state-owned companies. Subsidies to inefficient companies have been stopped. Tariff rates were reduced. The financial debt has been reduced and turned into a surplus of .8% in 1992. Mexico's foreign debt has been reduced from its high in 1987 of $107 billion. Agricultural reforms have been ongoing for 50 years. Land was redistributed, but standards of living and productivity have improved only slightly. Rural land tenure regulations have been changed, and other economic reforms are expected. Mexico engages in ad hoc international groups and is selective about membership in international organizations.

  11. Appendicularian distribution and diversity in the southern Gulf of Mexico Distribución y diversidad de apendicularias en el sur del golfo de México

    Directory of Open Access Journals (Sweden)

    César Flores-Coto

    2010-04-01

    Full Text Available The diversity and distribution of appendicularians on the continental shelf and upper part of the oceanic sea in the southern Gulf of Mexico is analyzed here for the first time. Samples were collected in September 2003 using a fine mesh net. Twenty species were identified, of which Fritillaria venusta and Pelagopleura oppressa are first records for the Gulf of Mexico. Oikopleura species occur throughout the area, with greatest abundances in the upwelling waters of the inner shelf off Yucatán and Campeche. The greatest abundances of Fritillaria species and of the other genera were recorded in the mid, outer shelf, and oceanic areas of Campeche and Tabasco that are influenced by continental water discharges and an oceanic gyre. Diversity and abundance varied in differing directions, with high abundance and low diversity characterizing the costal areas and low abundance and high diversity in the mid, outer shelf, and oceanic areas. The distribution of appendicularian species appears to be influenced by upwelling currents, gyres, water column depth, continental water discharges, salinity, and temperature. However, it could be assumed that the reasons behind these physical environmental factors include the food supply, a short life cycle, and high reproductive efficiency, factors that are commonly associated with distribution.Se analiza por primera vez la diversidad y distribución de las apendicularias en la capa superficial de la columna de agua de la plataforma continental del sur del Golfo de México. Las muestra se recolectaron en septiembre de 2003 usando una malla fina- Se identificaron 22 especies de las cuales Fritillaria venusta y Pelagopleura opresa tienen aquí su primer registro para el Golfo de México. Las especies de Oikopleura ocurrieron en toda el área con sus mayores abundancias en aguas de surgencia que corren sobre la plataforma de Yucatán y Campeche. La mayor abundancia de las especies de Fritillaria y de los otros g

  12. Submicron organic aerosol in Tijuana, Mexico, from local and Southern California sources during the CalMex campaign

    Science.gov (United States)

    Takahama, S.; Johnson, A.; Guzman Morales, J.; Russell, L. M.; Duran, R.; Rodriguez, G.; Zheng, J.; Zhang, R.; Toom-Sauntry, D.; Leaitch, W. R.

    2013-05-01

    The CalMex campaign was conducted from May 15 to June 30 of 2010 to study the properties and sources of air pollution in Tijuana, Mexico. In this study, submicron organic aerosol mass (OM) composition measured by Fourier Transform Infrared Spectroscopy (FTIR), Aerosol Chemical Speciation Monitor (ACSM), and X-ray spectromicroscopy are combined with statistical analysis and measurements of other atmospheric constituents. The average (±one standard deviation) OM concentration was 3.3 ± 1.7 μg m-3. A large source of submicron aerosol mass at this location was determined to be vehicular sources, which contributed approximately 40% to the submicron OM; largely during weekday mornings. The O/C ratio estimated from ACSM measurements was 0.64 ± 0.19; diurnal variations in this value and the more oxygenated fraction of OM as determined from Positive Matrix Factorization and classification analyses suggest the high degree of oxygenation originates from aged OM, rather than locally-produced secondary organic aerosol. A large contribution of this oxygenated aerosol to Tijuana from various source classes was observed; some fraction of this aerosol mass may be associated with non-refractory components, such as dust or BC. Backtrajectory simulations using the HYSPLIT model suggest that the mean wind vector consistently originated from the northwest region, over the Pacific Ocean and near the Southern California coast, which suggests that the origin of much of the oxygenated organic aerosol observed in Tijuana (as much as 60% of OM) may have been the Southern California Air Basin. The marine aerosol contribution to OM during the period was on average 23 ± 24%, though its contribution varied over synoptic rather than diurnal timescales. BB aerosol contributed 20 ± 20% of the OM during the campaign period, with notable BB events occurring during several weekend evenings.

  13. Proceedings of the Binational Conference on Libraries in California and Baja California (1st, Tijuana, Baja California, Mexico, January 13-14, 1984) = Memorias de la Primera Conferencia Binacional de Bibliotecas de las Californias.

    Science.gov (United States)

    Ayala, Marta Stiefel, Ed.; And Others

    This document includes the text of presentations given at the First Binational Conference on Libraries in California and Baja California, as well as minutes from four roundtables held at the conference. Following a prologue and a brief background on the conference, the following presentations are included: (1) "State Support for Public…

  14. Marine and brackish-water molluscan biodiversity in the Gulf of California, Mexico

    OpenAIRE

    Hendrickx, Michel E; Brusca, Richard C.; Mercedes Cordero; Germán Ramírez R.

    2007-01-01

    Una base de datos conteniendo información taxonómica, de distribución y datos ecológicos de 2194 especies de moluscos marinos (1528 Gastropoda, 565 Bivalvia, 59 Polyplacophora, 21 Scaphopoda, 20 Cephalopoda y un Monoplacophora) conocidos para el golfo de California, México, fue utilizada para analizar su distribución latitudinal y batimétrica, para definir su afinidad por los distintos substratos, y para elaborar un modelo de la biodiversidad para el área del estudio. El modelo fue basado en ...

  15. Preferencias de leche fresca de bovino del consumidor de Baja California, Mexico

    OpenAIRE

    Iliana Enriqueta Montaño Méndez; Belem Dolores Avendaño Ruiz; Ana Isabel Acosta Martínez; Francisco Javier Mesías Díaz

    2013-01-01

    El documento tiene como objetivo conocer las preferencias del consumidor de Baja California por leche de bovino y sus hábitos de consumo, así como identificar segmentos para el consumo de leche a partir de los principales atributos como presentación, tipo de grasa y precio, e identificar nichos de mercado para nuevos productos. Para determinar las preferencias del consumidor, se utilizaron técnicas del análisis de conjunto, análisis de segmentación y análisis de simulación. Para lo anterior, ...

  16. Thermal evolution of a sheared continental margin: Insights from the Ballenas transform in Baja California, Mexico

    Science.gov (United States)

    Seiler, Christian; Gleadow, Andrew J. W.; Fletcher, John M.; Kohn, Barry P.

    2009-07-01

    The Ballenas transform margin in central Baja California offers an unparalleled opportunity to study the thermal behaviour of a sheared continental margin during various stages of its evolution. Apatite fission track and (U-Th)/He results from two transects perpendicular to the coast reveal a pronounced latest Pliocene to Pleistocene (~ 1.8 Ma) heating event related to the Neogene opening of the Gulf of California. Proximity to a regional pre-rift unconformity indicates that samples remained at near-surface levels since Paleogene unroofing, despite having experienced reheating to maximum paleotemperatures within or above the fission track partial annealing zone. In general, maximum paleotemperatures during overprinting decrease from > 100-120 °C near the coast to below 60 °C ca. 5-8 km further inland, suggesting lateral heat flow from a source within the Gulf of California. Heat sources related to the structural development of the Ballenas transform fault, located approximately 1.5-4.5 km offshore from the two sample transects, most likely controlled the observed reheating. Overprinting patterns do not support conductive reheating due to reburial, magmatism or frictional shear. Instead, a pronounced thermal spike in between much less overprinted neighbouring samples strongly favours convective heating by hydrothermal fluids as the dominant overprinting process. Hydrothermal activity may be caused by either deep fluid circulation along newly formed shear zones of the transform fault or, more likely, magmatic leaking along the transform fault. Latest Pliocene to Pleistocene (~ 1.8 Ma) activity on the Ballenas transform fault is closely linked to extension in the Lower and Upper Delfín basins and provides a minimum age for the structural reorganisation and the relocation of extension in the northern Gulf of California. This study shows that hydrothermal activity can cause significant thermal events in a transform margin before the passage of the spreading centre

  17. Plio-pleistocene volcano-tectonic evolution of la Reforma Caldera, Baja California, Mexico

    Science.gov (United States)

    Demant, Alain; Ortlieb, Luc

    1981-01-01

    La Reforma volcanic complex, in east-central Baja California, shows a characteristic caldera structure, 10 km in diameter. The first eruptive stage, during the Pliocene, was manifested by ash and pumice falls and by subaqueous pumitic flows. In a second stage basic flows were deposited in a near-shore environment (subaerial and pillow lavas). During the early Pleistocene a large ignimbritic eruption, producing mainly pantelleritic tuffs, immediately predated the formation of the caldera itself. Afterwards, along marginal fractures of the caldera, some rhyolitic domes and flows partially covered the thick ignimbritic sheet. A block of Miocene substratum, in the center of the caldera, has been uplifted, nearly 1 km, by "resurgent doming". Small outcrops of diorite might constitute the top of coarse-grained crystallized magmatic bodies, and thus support the "resurgent doming" interpretation. A few basaltic cones were finally built on the flanks of the caldera complex; the latter are not related to the caldera history but to the extension tectonics of the Gulf of California which are also responsible for the Tortuga Island and the Holocene Tres Virgenes tholeiitic cones. South of la Reforma are found the highest (+300 m) Pleistocene marine deposits of the Gulf coast of Baja California. The uplift of this area is due in part to the positive epeirogenic movements of the whole peninsular crustal block, and also to the late doming of the caldera. On the coastal (eastern) flank of La Reforma complex up to seven stepped wave-cut terraces have been preserved, the highest reaching more than +150 m and the lowest ones +25 m. Lateral correlations of the marine terraces along the whole Gulf of California suggest that this volcano-tectonic uplift, that is still active, is of the order of 240 mm/10 3 y. The set of terraces is interpreted to be Middle (700-125 × 10 3y) to Upper (125-80 × 10 3y) Pleistocene, and is tentatively correlated with the paleoclimatic chronology of deep

  18. Tuberculosis testing among populations with high HIV risk in Tijuana, Baja California, Mexico

    Science.gov (United States)

    Velasquez, Michele G.; Laniado-Laborin, Rafael; Rodwell, Timothy C.; Cerecer, Paris; Lozada, Remedios; Cuevas-Mota, Jazmine; Burgos, Jose Luis; Garfein, Richard S.

    2013-01-01

    Objective To assess the prevalence of prior tuberculin skin testing (TST) among populations at risk for HIV infection in Tijuana, Mexico, and to identify factors associated with TST. Methods Sex workers, injection drug users, noninjecting drug users, and homeless persons ≥ 18 years old were recruited by using targeted sampling for risk assessment interviews and serologic testing for HIV and Mycobacterium tuberculosis infection. Univariate and multivariate logistic regression were used to identify correlates of self-reported TST history. Results Of 502 participants, 38.0% reported prior TST, which was associated with previous incarceration in the United States of America [odds ratio (OR) = 13.38; 95% confidence interval (CI) = 7.37–24.33] and injection drug use (OR = 1.99; 95% CI = 1.27–3.11). Positive results on serologic tests for M. tuberculosis infection (57%) and HIV (4.2%) were not associated with a prior TST. Conclusions A history of TST was lower in HIV-positive participants even though TST is indicated for persons with HIV in Mexico. Fewer than half the individuals at high risk for HIV in this study had a history of TST; however, TST was fairly common among those individuals with a prior history of incarceration. Increased tuberculosis screening is needed for populations at risk of contracting HIV in Tijuana, particularly those outside of criminal justice settings. PMID:22910722

  19. Validation of the ISAAC Standardized Questionnaire Used by Schoolchildren from Mexicali, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    Karla Gorozave-Car

    2013-01-01

    Full Text Available Background. In Mexico, several studies have been conducted under the ISAAC methodology; nevertheless, no validation studies of the ISAAC questionnaire based on objective clinical testing in our country have been published. Aims of the Study. To validate the ISAAC questionnaire, used in a study of prevalence of allergic diseases, based on medical, respiratory, and allergic evaluations of schoolchildren being 11 to 16 years old in Mexicali, Mexico. Material and Methods. We conducted a cross-sectional study to validate the ISAAC questionnaire through the generation of an index (considered as gold standard using pre- and postbronchodilator spirometry test, exhaled nitric oxide measurements, and atopic evaluations. 114 schoolchildren were included (23 asthmatics with respiratory symptoms and 91 nonasthmatics without respiratory symptoms and we evaluated the sensitivity, specificity, and positive and negative predictive value of the questionnaire using discriminant analysis. Results. We observed sensitivity of 35.2% and specificity of 93.3% and the positive and negative predictive values were 82.6% and 61.5%, respectively. Conclusions. Our findings indicate that the ISAAC Mexican version questionnaire was less sensitive and more specific when compared to the gold standard; however, it is adequate and able to discriminate children with and without asthma and a useful tool to use in epidemiological studies.

  20. Tuberculosis testing among populations with high HIV risk in Tijuana, Baja California, Mexico.

    Science.gov (United States)

    Velasquez, Michele G; Laniado-Laborin, Rafael; Rodwell, Timothy C; Cerecer, Paris; Lozada, Remedios; Cuevas-Mota, Jazmine; Burgos, Jose Luis; Garfein, Richard S

    2012-07-01

    To assess the prevalence of prior tuberculin skin testing (TST) among populations at risk for HIV infection in Tijuana, Mexico, and to identify factors associated with TST. Sex workers, injection drug users, noninjecting drug users, and homeless persons > 18 years old were recruited by using targeted sampling for risk assessment interviews and serologic testing for HIV and Mycobacterium tuberculosis infection. Univariate and multivariate logistic regression were used to identify correlates of self-reported TST history. Of 502 participants, 38.0% reported prior TST, which was associated with previous incarceration in the United States of America [odds ratio (OR) = 13.38; 95% confidence interval (CI) = 7.37-24.33] and injection drug use (OR = 1.99; 95% CI = 1.27- 3.11). Positive results on serologic tests for M. tuberculosis infection (57%) and HIV (4.2%) were not associated with a prior TST. A history of TST was lower in HIV-positive participants even though TST is indicated for persons with HIV in Mexico. Fewer than half the individuals at high risk for HIV in this study had a history of TST; however, TST was fairly common among those individuals with a prior history of incarceration. Increased tuberculosis screening is needed for populations at risk of contracting HIV in Tijuana, particularly those outside of criminal justice settings.

  1. Sea-surface temperature gradients across blue whale and sea turtle foraging trajectories off the Baja California Peninsula, Mexico

    Science.gov (United States)

    Etnoyer, Peter; Canny, David; Mate, Bruce R.; Morgan, Lance E.; Ortega-Ortiz, Joel G.; Nichols, Wallace J.

    2006-02-01

    Sea-surface temperature (SST) fronts are integral to pelagic ecology in the North Pacific Ocean, so it is necessary to understand their character and distribution, and the way these features influence the behavior of endangered and highly migratory species. Here, telemetry data from sixteen satellite-tagged blue whales ( Balaenoptera musculus) and sea turtles ( Caretta caretta, Chelonia mydas, and Lepidochelys olivacea) are employed to characterize 'biologically relevant' SST fronts off Baja California Sur. High residence times are used to identify presumed foraging areas, and SST gradients are calculated across advanced very high resolution radiometer (AVHRR) images of these regions. The resulting values are compared to classic definitions of SST fronts in the oceanographic literature. We find subtle changes in surface temperature (between 0.01 and 0.10 °C/km) across the foraging trajectories, near the lowest end of the oceanographic scale (between 0.03 and 0.3 °C/km), suggesting that edge-detection algorithms using gradient thresholds >0.10 °C/km may overlook pelagic habitats in tropical waters. We use this information to sensitize our edge-detection algorithm, and to identify persistent concentrations of subtle SST fronts in the Northeast Pacific Ocean between 2002 and 2004. The lower-gradient threshold increases the number of fronts detected, revealing more potential habitats in different places than we find with a higher-gradient threshold. This is the expected result, but it confirms that pelagic habitat can be overlooked, and that the temperature gradient parameter is an important one.

  2. Annual variation of biomass and photosynthesis in Zostera marina L. along the Pacific Coast of Baja California, Mexico

    Science.gov (United States)

    Cabello-Pasini, Alejandro; Munoz-Salazar, R.; Ward, D.H.

    2003-01-01

    Density, biomass, morphology, phenology and photosynthetic characteristics of Zostera marina were related to continuous measurements of in situ irradiance, attenuation coefficient and temperature at three coastal lagoons in Baja California, Mexico. In situ irradiance was approximately two-fold lower at San Quintin Bay (SQ) than at Ojo de Liebre Lagoon (OL) and San Ignacio Lagoon (SI). As a consequence of the greater irradiance plants at OL and SI were established 1 m deeper within the water column than those at SQ. At SQ, there was a four-fold variation in biomass of Z. marina caused by changes on shoot length and not shoot density, while at OL and SI biomass and shoot length did not fluctuate significantly throughout the year. Reproductive shoot density reached maximum values concomitantly with the greater irradiance during spring-summer, however, the density was approximately three-fold greater at SQ than at the southern coastal lagoons. While irradiance levels were two-fold greater at the southern lagoons, in general, photosynthetic characteristics were similar among all three lagoons. The hours of light saturated photosynthesis, calculated from their photosynthetic characteristics and irradiance measurements, suggest that photosynthesis of shoots from OL and SI are saturated for more than 6 h per day throughout the year, while shoots from SQ are likely light limited during approximately 15% of the year. Consequently, an increase in attenuation coefficient values in the water column will likely decrease light availability to Z. marina plants at SQ, potentially decreasing their survival.

  3. Polychlorinated biphenyls and biotransformation enzymes in three species of sea turtles from the Baja California peninsula of Mexico.

    Science.gov (United States)

    Richardson, K L; Lopez Castro, M; Gardner, S C; Schlenk, D

    2010-01-01

    Concentrations of polychlorinated biphenyls (PCBs) as well as the expression patterns of cytochrome P450 (CYP) enzymes and glutathione-S-transferase (GST) activities were measured in livers of loggerhead (Caretta caretta), green (Chelonia mydas), and olive ridley (Lepidocheyls olivacea) sea turtles from the Baja California peninsula of Mexico. The mean concentrations of total PCBs were 18.1, 10.5, and 15.2 ng/g wet weight (ww) respectively for the three species and PCB 153 was the dominant congener in all samples. Total PCB concentrations were dominated by penta- and hexa-chlorinated biphenyls. The mean estimated TEQs were 42.8, 22.9, and 10.4 pg/g (ww) for loggerhead, green, and olive ridley, respectively, and more than 70% was accounted for by non-ortho PCBs. Western blots revealed the presence of hepatic microsomal proteins that cross-reacted with anti-CYP2K1 and anti-CYP3A27 antibodies but not with anti-CYP1A antibody. There were no significant differences in GST activities between species. Grouping congeners based on structure-activity relationships for CYP isoenzymes suggested limited activity of CYP1A contribution to PCB biotransformation in sea turtles. These results suggest potential accumulation of PCBs that are CYP1A substrates and provide evidence for biotransformation capacity, which differs from known animal models, highlighting the need for further studies in reptiles, particularly those threatened with extinction.

  4. Total Mercury in Squalid Callista Megapitaria squalida from the SW Gulf of California, Mexico: Tissue Distribution and Human Health Risk.

    Science.gov (United States)

    Romo-Piñera, Abril K; Escobar-Sánchez, Ofelia; Ruelas-Inzunza, Jorge; Frías-Espericueta, Martín G

    2018-01-15

    We evaluated the total Hg concentration in different tissues of squalid callista Megapitaria squalida in order to measure Hg distribution in tissue and to estimate human health risk. Samples were obtained by free diving in the SW Gulf of California, Mexico. Concentrations are given on a wet weight basis. A total of 89 squalid callista specimens were obtained, presenting an average Hg concentration of 0.07 ± 0.04 µg g-1. There were no significant differences (p > 0.05) in Hg concentration between tissues (visceral mass = 0.09 ± 0.08 µg g-1; mantle = 0.06 ± 0.07 µg g-1; muscle = 0.06 ± 0.04 µg g-1). The low Hg values found in squalid callista and its low risk quotient (HQ = 0.03) suggest that the consumption of squalid callista does not represent a human health risk. However, HQ calculated using MeHg was > 1, it which could indicate a potential risk related to consumption of clams.

  5. Hazardous waste shipping in the northern border of Mexico: The situation of Baja California

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    Ramón A. Castillo Ponce

    2013-01-01

    Full Text Available In this document we evaluate the determinants of shipments of hazardous waste to the US. We consider a sample of firms operating in the state of Baja California for the 2008–2010 sample period. The analysis consists on the estimation of two econometric specifications. The first refers to a truncated model in the spirit of Tobit. The second is a probabilistic model. The results of the Tobit model suggest that size, location and origin of the firm influence the amount of shipments. In particular, shipments are positively associated with larger firms; those located in the municipality of Tijuana and those whose origin is foreign. The probabilistic model finds that a depreciation of the Mexican peso contributes to an increase in the likelihood of sending a shipment. This may be the result of an improvement in the border economic environment due to the depreciation of the currency.

  6. The microbial community at Laguna Figueroa, Baja California Mexico - From miles to microns

    Science.gov (United States)

    Stolz, J. F.

    1985-01-01

    The changes in the composition of the stratified microbial community in the sediments at Laguna Figeroa following floods are studied. The laguna which is located on the Pacific coast of the Baja California peninsula 200 km south of the Mexican-U.S. border is comprised of an evaporite flat and a salt marsh. Data collected from 1979-1983 using Landsat imagery, Skylab photographs, and light and transmission electron microscopy are presented. The flood conditions, which included 1-3 m of meteoric water covering the area and a remanent of 5-10 cm of siliciclastic and clay sediment, are described. The composition of the community prior to the flooding consisted of Microcoleus, Phormidium sp., a coccoid cynanobacteria, Phloroflexus, Ectothiorhodospira, Chloroflexus, Thiocapsa sp., and Chromatium. Following the floods Thiocapsa, Chromatium, Oscillatora sp., Spirulina sp., and Microcoleus are observed in the sediments.

  7. Feeding habits of the convict surgeonfish Acanthurus triostegus (Teleostei: Acanthuridae) in the Los Frailes reef, B.C.S., Mexico

    OpenAIRE

    Abitia Cárdenas, Leonardo Andrés; Moreno Sánchez, Xchel Gabrie; Palacios-Salgado, Deivis Samuel; Escobar-Sánchez, Ofelia

    2011-01-01

    Studies of the feeding habits of reef-inhabiting herbivorous species are important since they are the first level in the trophic chain between primary producers and consumers. This study is the first contribution to determine the diet of the convict surgeonfish Acanthurus triostegus from the Los Frailes reef, Baja California Sur, Mexico. We describe qualitative and quantitatively the trophic spectrum of 50 A. triostegus individuals, using the traditional methods of frequency of occurrence and...

  8. Submarine Neotectonic Investigations of the Bahia Soledad Fault, off Northern Baja California Near the US - Mexico Border

    Science.gov (United States)

    Anderson, K.; Lundsten, E. M.; Paull, C. K.; Caress, D. W.; Thomas, H. J.; Maier, K. L.; McGann, M.; Herguera, J. C.; Gwiazda, R.; Arregui, S.; Barrientos, L. A.

    2015-12-01

    The Monterey Bay Aquarium Research Institute (MBARI) conducted detailed surveys at selected sites on the seafloor along the Bahia Soledad Fault offshore of Northern Baja California, Mexico, during a two-ship expedition in the spring of 2015. The Bahia Soledad Fault is a NNW-trending strike-slip fault that is likely continuous with the San Diego Trough Fault offshore of San Diego, California. Constraining the style of deformation, continuity, and slip rate along this fault system is critical to characterizing the seismic hazards to the adjacent coastal areas extending from Los Angeles to Ensenada. Detailed morphologic surveys were conducted using an autonomous underwater vehicle (AUV) to provide ultra high-resolution multibeam bathymetry (vertical precision of 0.15 m and horizontal resolution of 1.0 m). The AUV also carried a 2-10 kHz chirp sub-bottom profiler and an Edgetech 110kHz and 410kHz sidescan. The two sites along the Bahia Soledad Fault each run ~6 km along the fault with ~1.8 km wide footprint. The resulting bathymetry shows these fault zones are marked with distinct lineations that are flanked by ~1 km long elongated ridges and depressions which are interpreted to be transpressional pop-up structures and transtensional pull-apart basins up to 100 m of relief. Offset seismic reflectors that extend to near the seafloor confirm that these lineations are fault scarps. The detailed bathymetric maps and sub-bottom profiles were used to locate key sites where deformed stratigraphic horizons along the fault are within 1.5 m of the seafloor. These areas were sampled using a remotely operated vehicle (ROV) equipped with a vibracoring system capable of collecting precisely located cores that are up to 1.5 m long. The coupled use of multibeam imagery and surgically-collected stratigraphic samples will enable to constrain the frequency and timing of recent movements on this fault which will be useful to incorporated into future seismic hazard assessment.

  9. Spatial distribution of heavy metals in urban dust from Ensenada, Baja California, Mexico

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    José L. Cortés

    2017-01-01

    Full Text Available E n Ensenada, Baja California, los barcos y vehículos emiten partículas con metales pesados. Las partículas se transportan con el viento y se depositan en el suelo, donde se mezclan con él dando lugar a los polvos urbanos. Los metales pesados pueden afectar la salud de la población, por lo que se requiere un diagnóstico rápido para encontrar soluciones. El objetivo de este trabajo fue identificar las zonas con mayor contaminación en la ciudad. Se tomaron 86 muestras de polvo urbano sobre diferentes sustratos (suelo, cemento y asfalto. Los metales se analizaron mediante f luorescencia de rayos X. Las diferencias entre los sustratos se identificaron mediante un análisis de varianza. Por otra parte, se hizo un análisis para conocer la distribución espacial de los metales pesados, utilizando la interpolación con kriging ordinario. El asfalto contiene las mayores concentraciones de Cr, Ni, Pb y Zn; el cemento contiene mayores concentracions de Cu y V; y el suelo es el que más Rb contiene. El mapa que integra las clases de mayor concentración de metales indica que la zona suroeste, donde se localiza el puerto y pasa la carretera transpeninsular, es la más contaminada.

  10. Nutrient fluxes and net metabolism in a coastal lagoon SW peninsula of Baja California, Mexico

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    Cervantes Duarte, R.

    2016-09-01

    Full Text Available Fluxes of nutrients and net metabolism were estimated in coastal lagoon Magdalena Bay using LOICZ biogeochemical model. In situ data were obtained from 14 sites in the lagoon and also from a fixed site in the adjacent ocean area. Intense upwelling (February to July and faint upwelling (August to January were analyzed from monthly time series. The Temperature, nitrite + nitrate, ammonium and phosphate within the lagoon showed significant differences (p<0.05 between the two periods. Salinity (p=0.408 was more homogeneous (no significantly different due to mixing processes. During the intense upwelling period, nutrients increased in and out of the lagoon due to the influence of Transitional Water and Subartic Water transported by the California Current. However, during the faint upwelling, from August to January, the Transition Water and Subtropical Surface Water were predominant. Magdalena Bay showed denitrification processes of throughout the year as it occurred in other semi-arid coastal lagoons. It also showed a net autotrophic metabolism during intense upwelling and heterotrophic metabolism during faint upwelling. Understanding nutrient flows and net metabolism through simple biogeochemical models can provide tools for better management of the coastal zone.

  11. Colorado river floods, droughts, and shrimp fishing in the upper gulf of California, Mexico.

    Science.gov (United States)

    All, John D

    2006-01-01

    Accurate procedures that measure hydrologic variability would have great value for evaluating ecosystem impacts of upstream water use in the Colorado River Basin. Many local extractive income-based stakeholders rely directly or indirectly on ecosystem health and are adversely affected when the river does not flow. This study focuses on the impact of little or no Colorado River flow on the Mexican shrimp industry. Although there have been complaints that U.S. diversions of Colorado River flow have greatly impaired the shrimp fishery, this research demonstrates that freshwater rarely reaches the Gulf even during times of flooding, and that other factors such as overfishing may influence the instability of shrimp populations. Advanced very-high-resolution radiometer (AVHRR) satellite imagery was used to assess water volumes diverted away from the channel of the Colorado River and ultimately the Gulf of California during flooding periods. Analysis of data demonstrated that little freshwater actually reaches the Gulf even during floods because of its diversion into a large dry lake bed basin known as Laguna Salada. Fuller use of the Colorado River throughout its entire course to the sea is possible and could benefit a large cohort of users without catastrophic habitat destruction in delta ecosystems. Reconstruction of a natural earthen berm, as proposed by Ducks Unlimited, would maximize the use of floodwaters for ecosystem benefits. These findings have profound implications for local economic activities dependent on hydrologic resources in the Colorado River Delta and Upper Gulf.

  12. Fish Larvae Response to Biophysical Changes in the Gulf of California, Mexico (Winter-Summer

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    Raymundo Avendaño-Ibarra

    2013-01-01

    Full Text Available We analyzed the response of fish larvae assemblages to environmental variables and to physical macro- and mesoscale processes in the Gulf of California, during four oceanographic cruises (winter and summer 2005 and 2007. Physical data of the water column obtained through CTD casts, sea surface temperature, and chlorophyll a satellite imagery were used to detect mesoscale structures. Zooplankton samples were collected with standard Bongo net tows. Fish larvae assemblages responded to latitudinal and coastal-ocean gradients, related to inflow of water to the gulf, and to biological production. The 19°C and 21°C isotherms during winter, and 29°C and 31°C during summer, limited the distribution of fish larvae at the macroscale. Between types of eddy, the cyclonic (January registered high abundance, species richness, and zooplankton volume compared to the other anticyclonic (March and cyclonic (September. Thermal fronts (Big Islands of January and July affected the species distribution establishing strong differences between sides. At the mesoscale, eddy and fronts coincided with the isotherms mentioned previously, playing an important role in emphasizing the differences among species assemblages. The multivariate analysis indicated that larvae abundance was highly correlated with temperature and salinity and with chlorophyll a and zooplankton volume during winter and summer, respectively.

  13. Preferencias de leche fresca de bovino del consumidor de Baja California, Mexico

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    Iliana Enriqueta Montaño Méndez

    2013-01-01

    Full Text Available El documento tiene como objetivo conocer las preferencias del consumidor de Baja California por leche de bovino y sus hábitos de consumo, así como identificar segmentos para el consumo de leche a partir de los principales atributos como presentación, tipo de grasa y precio, e identificar nichos de mercado para nuevos productos. Para determinar las preferencias del consumidor, se utilizaron técnicas del análisis de conjunto, análisis de segmentación y análisis de simulación. Para lo anterior, se diseñó y aplicó un cuestionario a una muestra representativa conformada por 418 consumidores del Estado, para conocer el producto ideal y caracterizar al consumidor bajo diferentes segmentaciones basados en sus preferencias. Los resultados muestran mayor preferencia por leche pasteurizada con tipo de grasa entera, a la cual le atribuyen mejor sabor, seguida por la leche ultra pasteurizada y las fórmulas lácteas. Además se encontró un segmento de mercado para nuevos productos y la valoración positiva al precio situación no habitual dentro de los consumidores agroalimentarios.

  14. Bimodal distribution of risk for childhood obesity in urban Baja California, Mexico.

    Science.gov (United States)

    Wojcicki, Janet M; Jimenez-Cruz, Arturo; Bacardi-Gascon, Montserrat; Schwartz, Norah; Heyman, Melvin B

    2012-08-01

    In Mexico, higher socioeconomic status (SES) has been found to be associated with increased risk for obesity in children. Within developed urban areas, however, there may be increased risk among lower SES children. Students in grades 4-6 from five public schools in Tijuana and Tecate, Mexico, were interviewed and weight, height and waist circumference (WC) measurements were taken. Interviews consisted of questions on food frequency, food insecurity, acculturation, physical activity and lifestyle practices. Multivariate logistic models were used to assess risk factors for obesity (having a body mass index [BMI] ≥95th percentile) and abdominal obesity (a WC >90th percentile) using Stata 11.0. Five hundred and ninety students were enrolled; 43.7% were overweight or obese, and 24.3% were obese and 20.2% had abdominal obesity. Independent risk factors for obesity included watching TV in English (odds ratio [OR] 1.60, 95% confidence interval [CI] 1.06-2.41) and perceived child food insecurity (OR 1.57, 95% CI 1.05-2.36). Decreased risk for obesity was associated with female sex (OR 0.64, 95% CI 0.43-0.96), as was regular multivitamin use (OR 0.63, 95% CI 0.42-0.94). Risk obesity was also decreased with increased taco consumption (≥1×/week; OR 0.64, 95% CI 0.43-0.96). Independent risk factors for abdominal obesity included playing video games ≥1×/week (OR 1.18, 95% CI 1.11-2.96) and older age group (10-11 years, OR 2.47, 95% CI 1.29-4.73 and ≥12 years, OR 2.21, 95% CI 1.09-4.49). Increased consumption of tacos was also associated with decreased risk for abdominal obesity (≥1×/week; OR 0.56, 95% CI 0.40-1.00). We found a bimodal distribution for risk of obesity and abdominal obesity in school aged children on the Mexican border with the United States. Increased risk for obesity and abdominal obesity were associated with factors indicative of lower and higher SES including watching TV in English, increased video game playing and perceived food insecurity

  15. Subsidence monitoring with geotechnical instruments in the Mexicali Valley, Baja California, Mexico

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    E. Glowacka

    2015-11-01

    Full Text Available The Mexicali Valley (northwestern Mexico, situated in the southern part of the San Andreas fault system, is an area with high tectonic deformation, recent volcanism, and active seismicity. Since 1973, fluid extraction, from the 1500–3000 m depth range, at the Cerro Prieto Geothermal Field (CPGF, has influenced deformation in the Mexicali Valley area, accelerating the subsidence and causing slip along the traces of tectonic faults that limit the subsidence area. Detailed field mapping done since 1989 (González et al., 1998; Glowacka et al., 2005; Suárez-Vidal et al., 2008 in the vicinity of the CPGF shows that many subsidence induced fractures, fissures, collapse features, small grabens, and fresh scarps are related to the known tectonic faults. Subsidence and fault rupture are causing damage to infrastructure, such as roads, railroad tracks, irrigation channels, and agricultural fields. Since 1996, geotechnical instruments installed by CICESE (Centro de Investigación Ciéntifica y de Educación Superior de Ensenada, B.C. have operated in the Mexicali Valley, for continuous recording of deformation phenomena. Instruments are installed over or very close to the affected faults. To date, the network includes four crackmeters and eight tiltmeters; all instruments have sampling intervals in the 1 to 20 min range. Instrumental records typically show continuous creep, episodic slip events related mainly to the subsidence process, and coseismic slip discontinuities (Glowacka et al., 1999, 2005, 2010; Sarychikhina et al., 2015. The area has also been monitored by levelling surveys every few years and, since the 1990's by studies based on DInSAR data (Carnec and Fabriol, 1999; Hansen, 2001; Sarychikhina et al., 2011. In this work we use data from levelling, DInSAR, and geotechnical instruments records to compare the subsidence caused by anthropogenic activity and/or seismicity with slip recorded by geotechnical instruments, in an attempt to obtain

  16. Subsidence monitoring with geotechnical instruments in the Mexicali Valley, Baja California, Mexico

    Science.gov (United States)

    Glowacka, E.; Sarychikhina, O.; Márquez Ramírez, V. H.; Robles, B.; Nava, F. A.; Farfán, F.; García Arthur, M. A.

    2015-11-01

    The Mexicali Valley (northwestern Mexico), situated in the southern part of the San Andreas fault system, is an area with high tectonic deformation, recent volcanism, and active seismicity. Since 1973, fluid extraction, from the 1500-3000 m depth range, at the Cerro Prieto Geothermal Field (CPGF), has influenced deformation in the Mexicali Valley area, accelerating the subsidence and causing slip along the traces of tectonic faults that limit the subsidence area. Detailed field mapping done since 1989 (González et al., 1998; Glowacka et al., 2005; Suárez-Vidal et al., 2008) in the vicinity of the CPGF shows that many subsidence induced fractures, fissures, collapse features, small grabens, and fresh scarps are related to the known tectonic faults. Subsidence and fault rupture are causing damage to infrastructure, such as roads, railroad tracks, irrigation channels, and agricultural fields. Since 1996, geotechnical instruments installed by CICESE (Centro de Investigación Ciéntifica y de Educación Superior de Ensenada, B.C.) have operated in the Mexicali Valley, for continuous recording of deformation phenomena. Instruments are installed over or very close to the affected faults. To date, the network includes four crackmeters and eight tiltmeters; all instruments have sampling intervals in the 1 to 20 min range. Instrumental records typically show continuous creep, episodic slip events related mainly to the subsidence process, and coseismic slip discontinuities (Glowacka et al., 1999, 2005, 2010; Sarychikhina et al., 2015). The area has also been monitored by levelling surveys every few years and, since the 1990's by studies based on DInSAR data (Carnec and Fabriol, 1999; Hansen, 2001; Sarychikhina et al., 2011). In this work we use data from levelling, DInSAR, and geotechnical instruments records to compare the subsidence caused by anthropogenic activity and/or seismicity with slip recorded by geotechnical instruments, in an attempt to obtain more information

  17. Halorubrum chaoviator sp. nov., a haloarchaeon isolated from sea salt in Baja California, Mexico, Western Australia and Naxos, Greece

    Science.gov (United States)

    Mancinelli, Rocco L.; Landheim, Ragnhild; Sanchez-Porro, Cristina; Dornmayr-Pfaffenhuemer, Marion; Gruber, Claudia; Legat, Andrea; Ventosa, Antonio; Radax, Christian; Ihara, Kunio; White, Melisa R.; Stan-Lotter, Helga

    2011-01-01

    Three halophilic isolates, strains Halo-G*T, AUS-1 and Naxos II, were compared. Halo-G* was isolated from an evaporitic salt crystal from Baja California, Mexico, whereas AUS-1 and Naxos II were isolated from salt pools in Western Australia and the Greek island of Naxos, respectively. Halo-G*T had been exposed previously to conditions of outer space and survived 2 weeks on the Biopan facility. Chemotaxonomic and molecular comparisons suggested high similarity between the three strains. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that the strains clustered with Halorubrum species, showing sequence similarities of 99.2–97.1 %. The DNA–DNA hybridization values of strain Halo-G*T and strains AUS-1 and Naxos II are 73 and 75 %, respectively, indicating that they constitute a single species. The DNA relatedness between strain Halo-G*T and the type strains of 13 closely related species of the genus Halorubrum ranged from 39 to 2 %, suggesting that the three isolates constitute a different genospecies. The G+C content of the DNA of the three strains was 65.5–66.5 mol%. All three strains contained C20C20 derivatives of diethers of phosphatidylglycerol, phosphatidylglyceromethylphosphate and phosphatidylglycerolsulfate, together with a sulfated glycolipid. On the basis of these results, a novel species that includes the three strains is proposed, with the name Halorubrum chaoviator sp. nov. The type strain is strain Halo-G*T (=DSM 19316T =NCIMB 14426T =ATCC BAA-1602T). PMID:19567575

  18. Could feeding habit and migratory behaviour be the causes of different toxicological hazard to cetaceans of Gulf of California (Mexico)?

    Science.gov (United States)

    Fossi, M C; Panti, C; Marsili, L; Maltese, S; Coppola, D; Jimenez, B; Muñoz-Arnanz, J; Finoia, M G; Rojas-Bracho, L; Urban, R J

    2014-12-01

    In this work, a suite of diagnostic biomarkers was applied to seven cetacean species to evaluate the role of the feeding habits and migratory behavior in the toxicological status of these species from the Gulf of California, Mexico. We investigate the interspecific differences in cytochrome P450 1A1 and 2B (CYP1A1 and CYP2B, respectively), aryl hydrocarbon receptor and E2F transcription factor 1 and the contaminants levels [organochlorine compounds, polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs)] in four odontocete species (common bottlenose dolphin, long-beaked common dolphin, sperm whale and killer whale) and three mysticete species (blue whale, fin whale, and Bryde's whale) using skin biopsy. Differences in contaminant levels and molecular biomarker responses between the odontocete and mysticete species have been pointed out. The canonical discriminant analysis on principal component analysis factors, performed to reveal clustering variables, shows that odontocete are characterised by the highest levels of lipophilic contaminants compared to the mysticete, with the highest levels of polychlorinated biphenyls, dichlorodiphenyltrichloroethanes and PBDEs detected in killer whale and the lowest levels in Bryde's whale. The biomarker data show interspecific differences amongst the seven species, revealing highest CYP1A and CYP2B protein levels in the mysticete fish-eating species (Bryde's whale). In conclusion, three main factors seem to regulate the biomarker responses in these species: (a) the inductive ability of persistent organic pollutants and PAHs; (b) the different evolutionary process of the two CYPs related to the different feeding habits of the species; (c) the migratory/resident behaviour of the mysticete species in this area.

  19. Application of MODIS-ASTER (MASTER) simulator data to geological mapping of young volcanic regions in Baja California, Mexico

    Science.gov (United States)

    Dmochowski, Jane Ellen

    Visible, near infrared, short-wave infrared, and thermal infrared multi-channel remote sensing data, MODIS-ASTER (MASTER), are used to extract geologic information from two volcanic regions in Baja California, Mexico: Tres Virgenes-La Reforma Volcanic Region and the volcanic island of Isla San Luis. The visible and near infrared and short-wave infrared data were atmospherically corrected and classified. The resulting classification roughly delineates surfaces that vary in their secondary minerals. Attempts to identify these minerals using ENVI's Spectral Analyst(TM) were moderately successful. The analysis of the thermal infrared data utilizes the shift to longer wavelengths in the Reststrahlen band as the mineralogy changes from felsic to mafic to translate the data into values of weight percent SiO2. The results indicate that the general approach tends to underestimate the weight percent SiO2 in the image. This discrepancy is removed with a "site calibration," which provides good results in the calculated weight percent SiO2 with errors of a few percent. However, errors become larger with rugged topography or low solar angle at the time of image acquisition. Analysis of bathymetric data around Isla San Luis, and consideration of the island's alignment with the Ballenas transform fault zone to the south and volcanic seamounts nearby, suggest Isla San Luis is potentially volcanically active and could be the product of a "leaky" transform fault. The results from the image analysis in the Tres Virgenes-La Reforma Volcanic Region show the La Reforma and El Aguajito volcanic centers to be bimodal in composition and verify the most recent volcanism in the Tres Virgenes region to be basaltic-andesite. The results of fieldwork and image analysis indicate that the volcanic products of the central dome of La Reforma are likely a sequence of welded ash flow tuffs and lavas of varied composition, evidence of its origin as a caldera.

  20. Genesis and evolution of the Cerro Prieto Volcanic Complex, Baja California, Mexico

    Science.gov (United States)

    García-Sánchez, L.; Macías, J. L.; Sosa-Ceballos, G.; Arce, J. L.; Garduño-Monroy, V. H.; Saucedo, R.; Avellán, D. R.; Rangel, E.; Layer, P. W.; López-Loera, H.; Rocha, V. S.; Cisneros, G.; Reyes-Agustín, G.; Jiménez, A.; Benowitz, J. A.

    2017-06-01

    The Cerro Prieto Volcanic Complex (CPVC), located in northwestern Mexico, is the only surface manifestation of the Cerro Prieto Geothermal Field, the third largest producer of geothermal energy in the world. This geothermal field and the Salton Sea in the USA sit in a pull-apart basin that belongs to the trans-tensional tectonic zone that includes the San Andreas Fault system and the Salton Trough basin to the NW and the East Pacific Rise to the SE. In spite of its strategic importance in the generation of geothermal energy, the origin of Cerro Prieto and its relationship with the geothermal reservoir were unknown. In this contribution, we discuss the origin, evolution, and mechanisms of formation of this small monogenetic volcano and the magmas that fed the system. The volcanic complex is located on top of the Cerro Prieto left lateral fault to the northwest of the Cerro Prieto Geothermal Field. The complex consists of a lava cone and a series of domes (˜0.15 km3) protruding from Tertiary sandstones and recent unconsolidated sediments of the alluvial plain of the Colorado River. The Cerro Prieto Volcanic Complex consists of seven stratigraphic units emplaced in a brief time span around 78-81 ka. Its activity began with the extrusion of a dacitic lava that came into contact with water-saturated sediments, causing brecciation of the lava. The activity continued with the emplacement of dacitic domes and a dyke that were destroyed by a phreatic explosion emplacing a lithic-rich breccia. This phreatic explosion formed a 300-m-wide and 40-m-deep circular crater. The activity then migrated ˜650 m to the SW where three dacitic lava domes were extruded and ended with the emplacement of a fissure-fed lava flow. Subsequent remobilization of the rocks in the complex has generated debris and hyperconcentrated flow deposits interbedded with fluviatile sediments in the surrounding terrain. All rocks of the CPVC are dacites with phenocrysts of plagioclase, orthopyroxene, and Fe

  1. Community Liaison as Factor for Image and Positioning of the Autonomous University of Baja California, Mexico, in the Social and Productive Context

    Directory of Open Access Journals (Sweden)

    Víctor Manuel Alcántar Enríquez

    2009-05-01

    Full Text Available This study presents the results of an extensive research on the society’s perceptions of the activities the Autonomous University of Baja California (UABC, for its acronym in Spanish Universidad Autónoma de Baja California develops in Mexico. This non-experimental research uses an explorative-descriptive methodology, with a transactional research design based on a holistic method and an illuminative evaluation, which analyzes the institutional positioning of UABC in several social sectors, as well as its determining factors. Results support the hypothesis that liaison activities have a significant effect on the regional positioning of the UABC as a higher education institution. The results also helped to identify weaknesses and opportunities that could direct future institutional efforts. In addition, this study provides new elements on liaison, institutional image, and positioning, as well as a conceptual model that involves these variables.

  2. Pandemic (H1N1) 2009 Surveillance in Marginalized Populations, Tijuana, Mexico, and West Nile Virus Knowledge among Hispanics, San Diego, California, 2006

    Centers for Disease Control (CDC) Podcasts

    2010-08-10

    This podcast describes public health surveillance and communication in hard to reach populations in Tijuana, Mexico, and San Diego County, California. Dr. Marian McDonald, Associate Director of CDC's Health Disparities in the National Center for Emerging and Zoonotic Infectious Diseases, discusses the importance of being flexible in determining the most effective media for health communications.  Created: 8/10/2010 by National Center for Emerging and Zoonotic Infectious Diseases, National Center for Immunization and Respiratory Diseases.   Date Released: 8/10/2010.

  3. [Seasonal and spatial structure of reef fish community in San Jose Island, Gulf of California, Mexico].

    Science.gov (United States)

    Barjau, Emelio; Rodríguez-Romero, Jesús; Galván, Felipe; Gutiérrez, Francisco; López, Juana

    2012-06-01

    The Gulf of California is one of the most fish diverse areas of the Tropical Eastern Pacific Ocean. In spite of its economic value, few works have considered fish community studies for optimum management. With the aim to determine the seasonal and spatial variation of fish communities in eight locations around the San José Island, some ecological research was conducted from March 2001 to February 2002. For this, visual censuses were used in 48 transects of 100x5m (500m2); specific analysis such as diversity values, the relative abundance and the biological value indexes were undertaken, and a principal component analysis applied. Our results clearly showed two climatic seasons of cold and warm waters. A total number of 26 608 organisms of 112 species and 76 genera of fishes were identified. We used the relative abundance index to determine the most important species, which were: Abudefduf troschelii, Thalassoma lucasanum, Stegastes rectifraenum, Mulloidichthys dentatus, Chromis atrilobata, Lutjanus argentiventris and Scarus ghobban. February was the month with the lowest diversity with a value of 3.12bits/ind. and October was the most diverse (4.13bits/ind.). According to the biological value index (BVI) and considering the climatic seasons, the fish species with the highest score during cold months were: A. troschelii, M. dentatus, S. ghobban, S. rectifraenum and T lucasanum. Besides, for warmer months, the same fish species were observed but in different order and abundance: A. troschelii, S. ghobban, S. rectifraenum, T lucasanum and M. dentatus. Using the biological value index, 13 species were those which had a higher overall score. The locations by the Eastern side of the island had a greater number of species and abundance of fish. The principal component analysis (PCA) applied using the seasonal data, species richness, diversity, equity, number of species and total abundance during the warmer months also a PCA within spatial data, showed that location in

  4. Oceanographic data acquired in support of the June 1980 study of the upwelling center off Point Sur, California (NODC Accession 9000024)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Current, Temperature and Depth (CTD) data were collected by Naval Postgraduate School from Coastal Waters of California between 2-19 June, 1980 using ship...

  5. Twentieth century demographic changes in cirio and cardón in Baja California, Mexico

    Science.gov (United States)

    Bullock, Stephen H.; Martijena, Nora E.; Webb, Robert H.; Turner, Raymond M.

    2005-01-01

    Aim  Our purpose was to discern long-term large-scale patterns of survivorship and recruitment of two dominant, charismatic and useful desert plants, cirio [Fouquieriaceae; Fouquieria columnaris (Kell.) Kell. ex Curran] and cardón [Cactaceae; Pachycereus pringlei(S.Watson) Britton & Rose], and to evaluate the effects of physical and human factors. Location  The study included 77 sites distributed over c. 13,200 km2 in the northern Vizcaíno Region of the Sonoran Desert, state of Baja California, México. Method  Censuses used identified individuals (n = 3780 cirio and 2246 cardón) and were based on repeat photography. Time intervals between censuses ranged from 29 to 96 years, ending in 1996–2002. Earlier repetition (1963) of old photographs at 14 sites allowed analysis of temporal variation. The effect of elapsed time was modelled with Weibull functions for survivorship and linear functions for recruitment. To explain the residual variations, we tested categorical and continuous variables related to substrate, geomorphology, climate and geography. Human impacts were weighed with historical and quantitative analysis. Results  Elapsed time accounted for 45% of the variation of survivorship in cirio but only 35% in cardón. The fitted Weibull curves were used to estimate longevity: all-size cohorts of 1000 individuals would die out in 388 (cirio) and 723 years (cardón). Recruitment in cirio was linearly related to time (r2 = 0.71) and averaged  0.005 year−1, was linearly related to time (r2 = 0.66) and was less than mortality at only 33% of the sites. Vital rates were not strongly correlated between mid- and late-century but were mostly similar to the long-term regional rates. Removing the factor of elapsed time, the residual variations showed that survivorship was greater on sites protected from winds for cirio and was less on very coarse soils for cardón. Recruitment increased with latitude in cirio and was greater on southern

  6. Blooms of Cochlodinium polykrikoides (Gymnodiniaceae in the Gulf of California, Mexico

    Directory of Open Access Journals (Sweden)

    I Gárate-Lizárraga

    2004-09-01

    Full Text Available Cochlodinium polykrikoides was the species responsible for the discoloration that occurred between September 15th and 27th , 2000 in a shallow coastal lagoon located in the southern part of the Bahía de La Paz, on the west side of the Gulf of California. Blooms of C. polykrikoides were observed four days after two rainy days with a seawater temperature of 29 to 31°C. Nutrient concentration ranges during the bloom were 0.165- 0.897 µM NO2 +NO3 , 0.16-3.25 µM PO4 , and 1.0-35.36 µM SiO4 . Abundance of C. polykrikoides ranged from 360 x 10³ to 7.05 x 10(6 /cells l-1 . Biomass expressed in terms of chlorophyll a was high, ranging from 2.7 to 56.8 mg/m³ . A typical dinoflagellate pigment profile (chlorophyll a and c, peridinin, diadinoxantin, and beta -carotene was recorded. In this study, the red tide occurred in front of several fish and shrimp-culture ponds. No PST toxins were found in the samples. However, 180 fish were found dead in the infected fish-pond; the gills were the most affected part. C. polykrikoides is a cyst-forming species that recurs in this area. New blooms were observed in November 2000 and September-November 2001 in the same area. Anthropogenic activities, such as eutrophication caused by water discharge in this shallow lagoon, and nutrient enrichment in the culture ponds, as well as effects from precipitation and wind stress, could have favored the outbreak of this dinoflagellateDurante el desarrollo de una marea roja ocurrida del 15 al 27 de septiembre del año 2000 en la Ensenada de La Paz, B.C.S. se tomaron muestras de agua con una botella Van Dorn para determinar la temperatura, la especie causante y la cantidad de nutrientes y pigmentos fotosintéticos. Se hicieron análisis de toxinas de Cochlodinium polykrikoides, la especie responsable de esta marea roja. La mayoría de los especimenes formaron cadenas de cuatro células y raramente de dos. La abundancia fue de 360 x 10³ a 7.05 x 10(6 /cels l-1 . Los

  7. Caracterización de Tagetes filifolia del centro-sur de México por morfometría de los aquenios Characterization of Tagetes filifolia from central-south Mexico by morphometric achene traits

    Directory of Open Access Journals (Sweden)

    Carlos A. Núñez-Colín

    2011-06-01

    Full Text Available Tagetes filifolia Lag. es una especie ruderal ampliamente distribuida en México de la cual se empieza a conocer su variabilidad morfológica, como parte de una serie de estudios relacionados con su posible domesticación para obtener biopesticidas. Para ampliar el conocimiento sobre este recurso vegetal se definieron mediante 11 características del aquenio 104 recolecciones del centro-sur de México empleando una técnica digital de imágenes. Se identificaron 5 diferentes grupos morfológicos. El Grupo I presentó recolecciones con aquenios pequeños y anchos; el Grupo II, aquenios grandes y anchos; el Grupo III, aquenios pequeños y alargados; el Grupo IV, aquenios grandes y alargados, y el Grupo V, aquenios grandes pero más alargados que los del Grupo IV. Las variables más discriminantes fueron el índice de alargamiento, índice de compactación, índice de redondez, relación eje menor/ eje mayor para la raíz canónica 1, y perímetro longitudinal y longitud del eje mayor para la raíz canónica 2. La gran variabilidad de las características de la forma y tamaño de los aquenios de T. filifolia se pudo agrupar en 5 morfotipos, los cuales no estuvieron presentes en toda la región centro-sur de México.Tagetes filifolia Lag. is a ruderal species widely distributed in Mexico from which is starting to make knowledge about its morphological variability as a part of a study sequence related with its possible domestication to obtain biopesticides. For acquiring more knowledge on this plant resource, 104 accessions from central-south Mexico were morphologically characterized by 11 achene traits employing a digital images technique. Five different morphologic groups were identified. Group I had accessions with small and wide achenes, group II had big and wide achenes, group III had small and long achenes, group IV had big and long achenes, and group V had big achenes but longer than group IV. The most discriminant variables were elongation

  8. Testing Pixel Translation Digital Elevation Models to Reconstruct Slip Histories: An Example from the Agua Blanca Fault, Baja California, Mexico

    Science.gov (United States)

    Wilson, J.; Wetmore, P. H.; Malservisi, R.; Ferwerda, B. P.; Teran, O.

    2012-12-01

    We use recently collected slip vector and total offset data from the Agua Blanca fault (ABF) to constrain a pixel translation digital elevation model (DEM) to reconstruct the slip history of this fault. This model was constructed using a Perl script that reads a DEM file (Easting, Northing, Elevation) and a configuration file with coordinates that define the boundary of each fault segment. A pixel translation vector is defined as a magnitude of lateral offset in an azimuthal direction. The program translates pixels north of the fault and prints their pre-faulting position to a new DEM file that can be gridded and displayed. This analysis, where multiple DEMs are created with different translation vectors, allows us to identify areas of transtension or transpression while seeing the topographic expression in these areas. The benefit of this technique, in contrast to a simple block model, is that the DEM gives us a valuable graphic which can be used to pose new research questions. We have found that many topographic features correlate across the fault, i.e. valleys and ridges, which likely have implications for the age of the ABF, long term landscape evolution rates, and potentially provide conformation for total slip assessments The ABF of northern Baja California, Mexico is an active, dextral strike slip fault that transfers Pacific-North American plate boundary strain out of the Gulf of California and around the "Big Bend" of the San Andreas Fault. Total displacement on the ABF in the central and eastern parts of the fault is 10 +/- 2 km based on offset Early-Cretaceous features such as terrane boundaries and intrusive bodies (plutons and dike swarms). Where the fault bifurcates to the west, the northern strand (northern Agua Blanca fault or NABF) is constrained to 7 +/- 1 km. We have not yet identified piercing points on the southern strand, the Santo Tomas fault (STF), but displacement is inferred to be ~4 km assuming that the sum of slip on the NABF and STF is

  9. Whole genome sequencing of Mycobacterium bovis to obtain molecular fingerprints in human and cattle isolates from Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    Sarai Estrella Sandoval-Azuara

    2017-10-01

    Conclusions: All isolates from humans had spoligotype patterns that matched those observed in the cattle isolates, and all human isolates shared common ancestors with cattle in Baja California based on SNP analysis. This suggests that most human tuberculosis caused by M. bovis in Baja California is derived from M. bovis circulating in Baja California cattle. These results reinforce the importance of bovine tuberculosis surveillance and control in this region.

  10. Human rights of immigrants from the southern border of Mexico / Los derechos humanos de los inmigrantes de la frontera sur de México

    Directory of Open Access Journals (Sweden)

    Rosa Cornelio Landero

    2015-10-01

    Full Text Available Human rights of migrants in various borders in the world is one of the social and political phenomena that has worried many international organizations, which always seeks to fight for the rights that persists in the situation of people the climate of impunity and violations that are immigrants arriving in a state, because they are persecuted by flee their homes by armed conflict, among other circumstances, a situation that Mexico is considered one of the countries that concentrates more migrants passing through the southern border of Mexico to reach the United States (USA. This work is in order to know what the international and Mexican standards protecting migrants in transit through the Southern Border of Mexico, analyze what rights are there in person Immigrant are considered when violate Human Rights as a person.

  11. Replacement names for two homonyms of Liothrips brevitubus Karny: one from California, the other for a species damaging Jatropha crops in Mexico.

    Science.gov (United States)

    Mound, Laurence; Goldarazena, Arturo; Lopez-Guillen, Guillermo; Hance, Thierry

    2016-12-21

    There are nearly 280 species of Liothrips listed from around the world (ThripsWiki 2016), all of them presumably feeding and breeding on the leaves of higher plants, and sometimes inducing or being associated with galls (Mound 1994). Despite this, for most of these species the identity of the plant species on which they are dependent is rarely known, and a particularly high proportion of the species are based on few specimens or even single individuals (cf Table 1). As a result, the identity of many of these named species continues to be in doubt. Modern identification keys are available only to the 23 Liothrips species known from Japan (Okajima 2006), the four European species known from Iran (Minaei & Mound 2014), and 14 species from Illinois (Stannard 1968). In contrast, the keys to 16 species of Liothrips from Brazil (Moulton 1933), to more than 80 species from Indonesia (Priesner 1968), and to 50 species from India (Ananthakrishnan & Sen 1980), are of little more than archival interest, in that they are based on few specimens with little allowance for intraspecific variation. Mound & Marullo (1996) listed over 80 Liothrips species from the Americas, although some of these are now placed in Pseudophilothrips (see Mound et al. 2010). That list included two homonyms of the Indonesian species Liothrips brevitubus Karny, one from Mexico and one from California. The homonym from Mexico is here recognised as applying to a species that in 2015 caused severe damage to a crop of Jatropha curcas in Chiapas. The objectives here are to provide a valid name for this pest, to facilitate its recognition among the 13 species of Liothrips recorded from Mexico (Table I), and also to replace the homonym from California.

  12. Mortality trends and risk of dying from colorectal cancer in the seven socioeconomic regions of Mexico, 2000-2012.

    Science.gov (United States)

    Sánchez-Barriga, J J

    In Mexico, there has been an upward trend in mortality rates from colorectal cancer (CRC) over the past three decades. This tumor is ranked among the ten most prevalent causes of morbidity from malignancies in Mexico. To determine the mortality trends by socioeconomic region and by state, and to establish the relative risk between both educational level and socioeconomic region with mortality from CRC within the time frame of 2000-2012. Records of mortality associated with colorectal cancer were obtained. Rates of mortality by state and by socioeconomic region were calculated, along with the strength of association (obtained through the Poisson regression) between both socioeconomic region and educational level and the mortality from CRC. A total of 45,487 individuals died from CRC in Mexico from 2000 to 2012. Age-adjusted mortality rates per 100,000 inhabitants increased from 3.9 to 4.8. Baja California, Baja California Sur, and Sonora had the highest mortality from CRC. Individuals with no school or incomplete elementary school had a higher risk of dying from this cancer (RR of 3.57, 95% CI: 3.46-3.68). Region 7 had the strongest association with mortality from CRC (Mexico City: RR was 2.84, 95% CI: 2.39-3.37 [2000] and 3.32, 95% CI: 2.89-3.82 [2012]). In Mexico, the age-adjusted mortality rates per 100,000 inhabitants that died from CRC increased from 3.9 to 4.8 in the study period, using the world population age distribution as the standard. Baja California, Baja California Sur, and Sonora had the highest mortality from CRC. Mexico City, which was socioeconomic region 7, had the strongest association with mortality from CRC. Copyright © 2017 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.

  13. The effects of sudden oak death and wildfire on forest composition and dynamics in the Big Sur Ecoregion of Coastal California

    Science.gov (United States)

    Margaret R. Metz; Kerri M. Frangioso; Ross K. Meentemeyer; David M. Rizzo

    2012-01-01

    Sudden oak death (SOD), caused by Phytophthora ramorum, is an emerging forest disease associated with extensive tree mortality in coastal California forests (Rizzo et al. 2005). P. ramorum is a generalist pathogen that infects many hosts, but hosts differ in their ability to transmit the disease...

  14. Evolution of the 2014-2015 sea surface temperature warming in the central west coast of Baja California, Mexico, recorded by remote sensing

    Science.gov (United States)

    Robinson, Carlos J.

    2016-07-01

    Extraordinarily warm sea surface temperatures were present in the California Current System during 2014-2015. In several locations surface waters temperature registered new record high in the recent time series. This study focuses in the evolution of the warming in the southern part of the California Current System (CCS), off the west coast of Baja California, Mexico. Analysis of monthly sea surface temperature (SST), sea level pressure, and wind speed as measured by satellite from January 1988 to December 2015 show that recent warming occurred during two distinct periods. From May 2014 to April 2015, SST warming was related to weak coastal winds not associated to El Niño. During this period occurred the longest sustained record of 15 months of negative wind anomalies in the series. A reduction of wind stress suggests a weakened coastal upwelling, and consequently, cold water not transported into the surface. The second process of warming occurred from September to December 2015, during a strong El Niño condition.

  15. New constraints on relative motion between the Pacific Plate and Baja California microplate (Mexico) from GPS measurements

    Science.gov (United States)

    Plattner, C.; Malservisi, R.; Dixon, T. H.; LaFemina, P.; Sella, G. F.; Fletcher, J.; Suarez-Vidal, F.

    2007-09-01

    We present a new surface velocity field for Baja California using GPS data to test the rigidity of this microplate, calculate its motion in a global reference frame, determine its relative motion with respect to the North American and the Pacific plates, and compare those results to our estimate for Pacific-North America motion. Determination of Pacific Plate motion is improved by the inclusion of four sites from the South Pacific Sea Level and Climate Monitoring Project. These analyses reveal that Baja California moves as a quasi-rigid block but at a slower rate in the same direction, as the Pacific Plate relative to North America. This is consistent with seismic activity along the western edge of Baja California (the Baja California shear zone), and may reflect resistance to motion of the eastern edge of the Pacific Plate caused by the `big bend' of the San Andreas fault and the Transverse Ranges in southern California.

  16. Status of the peregrine falcon in the Rocky Mountains and the southwestern United States, Baja California, and Mexico (south of Texas)

    Science.gov (United States)

    Porter, Ron; Craig, G.R.; Ellis, D.H.; Enderson, J.H.; Hunt, W.G.; Schaeffer, Philip P.; Ehlers, Sharyn M.

    1978-01-01

    About 31 pairs of peregrines still nest north of Mexico, from Idaho and Montana south through West Texas, New Mexico and Arizona. At least thirty-six additional pairs nest in Mexico. Although the nesting sites are occupied, the tissues of the peregrine?s prey species still contain high concentrations of pesticides. The eggs in some Rocky Mountain eyries have shells which are precariously thin and have high residue levels of DDE in their contents. Increasing economic development is encroaching on the peregrine habitat throughout its range in western North America. In Baja California. and Mexico south of Texas this involves increased agricultural activity including use of organochlorine pesticides, increased tourism and increased use of the Gulf of California both for commercial and sport fishing, with their potential disturbance of eyrie sites and reduction of the peregrine?s aquatic feeding prey base. As the fish in the Gulf decrease in number, some of the avian species on which peregrines prey will likewise decrease. This ultimately may effect the peregrine. These factors may have been involved in the demise of the peregrine on Baja California?s Pacific coast. Furthermore, throughout its range, residential, industrial, mining, geothermal, recreational and other types of development and land use practices sometimes destroy habitat essential to the survival of the peregrine. A recent request for the protection of an historical site in California as Critical Habitat under Section 7 of the Endangered Species Act was rejected because peregrines, although observed there, were not known to have produced eggs or young at the site for several decades. With inadequate protection of abandoned, but still suitable, historical eyrie sites, the peregrine may have an insufficient number of eyries to reoccupy in recovery attempts. The lack of present occupancy of a site, without biological evidence that the site is no longer suitable for reoccupancy, is insufficient cause to give

  17. California Immigrants Today

    OpenAIRE

    Cornelius, Wayne A.

    1990-01-01

    This paper will focus on the Mexico-origin component of the California immigrant population. Drawing on the results of field studies conducted throughout California and in west-central Mexico during the last ten years,the paper will describe how the profile of Mexican migration to California has changed since the 197Os, suggest explanations for these changes, and discuss their implications for public policy. Effects of the long-running economic crisis in Mexico and of the 1986 U.S. immigra-ti...

  18. Valor de existencia del servicio ecosistémico hidrológico en la Reserva de la Biosfera Sierra La Laguna, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Ismael SÁNCHEZ BRITO

    2013-01-01

    Full Text Available En la Reserva la principal fuente de abastecimiento es el agua subterránea y debido al acelerado crecimiento en la región sur del estado se ha planteado la necesidad de extraer agua para fines de provisión lo cual ha superado la capacidad de recarga de los acuíferos conduciendo a un déficit hídrico. Por esta razón, el objetivo del presente trabajo fue calcular el valor de existencia que provee el servicio ecosistémico de captación de agua de lluvia que permite la recarga de los acuíferos por medio del método de valoración contingente. La disposición a pagar (DAP fue de 93 a 114 pesos.

  19. Cadmium and phosphate variability during algal blooms of the dinoflagellate Lingulodinium polyedrum in Todos Santos Bay, Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez-Mejia, E. [Posgrado en Oceanografía Costera, Instituto de Investigaciones Oceanológicas/Facultad de Ciencias Marinas, Universidad Autónoma de Baja California, Campus Sauzal, Carretera Transpeninsular Ensenada-Tijuana No. 3917, Ensenada, Baja California CP 22860 (Mexico); Lares, M.L., E-mail: llares@cicese.mx [División de Oceanología, Departamento de Oceanografía Biológica, Centro de Investigación Científica y de Educación Superior de Ensenada, Km 107 Carretera Transpeninsular Ensenada-Tijuana, Ensenada, Baja California CP 22880 (Mexico); Huerta-Diaz, M.A.; Delgadillo-Hinojosa, F. [Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Campus Sauzal, Carretera Transpeninsular Ensenada-Tijuana No. 3917, Ensenada, Baja California CP 22860 (Mexico)

    2016-01-15

    Dinoflagellate algal blooms (DABs), with Lingulodinium polyedrum as the dominant species, have increased over the past few years in coastal areas off Baja California, Mexico. Vertical and temporal variability of particulate cadmium (Cd{sub p}), dissolved Cd (Cd{sub d}), PO{sub 4}{sup 3−} and Cd{sub d}/PO{sub 4}{sup 3−} were investigated during two intense DABs of L. polyedrum that occurred during the fall of 2011 and 2012 in Todos Santos Bay. Results were then, compared with data gathered in the absence of algal blooms during the autumn of 2013. In both algal blooms, L. polyedrum tended to be concentrated near the surface throughout the duration; however, during DAB 2011 the number of cells was twice as abundant ([10.0 ± 8.0] × 10{sup 5} cells L{sup −1}) as in DAB 2012 ([5.0 ± 4.4] × 10{sup 5} cells L{sup −1}). During DAB 2011, Cd{sub p} increased significantly (up to 1.02 ± 0.99 nmol kg{sup −1}) and was positively correlated with the cell abundance of L. polyedrum, suggesting that this dinoflagellate is able to assimilate and concentrate Cd{sub d}. Likewise, Cd{sub d} (up to 0.71 ± 0.17 nM) increased in the days of highest cell abundance, which could be attributed to uptake and subsequent regeneration of Cd{sub d} resulting from the remineralization of organic particulate matter produced during the bloom, as well as with the presence of organic ligands secreted by L. polyedrum that could keep Cd{sub d} in solution. During DAB 2011, dissolved Cd{sub d}/PO{sub 4}{sup 3−} ratios exhibited high vertical and temporal variability in the upper 5 m of the water column, but remained virtually constant near the bottom, suggesting a depth-dependent decoupling between these two dissolved components during the bloom development. Given the observed differences in the vertical and temporal variability of Cd{sub d}, Cd{sub p}, and PO{sub 4}{sup 3−} between these two intense DABs, we propose the existence of an abundance threshold of approximately 10{sup 6

  20. April 2008 Scripps Institute of Oceanography (SIO) Lidar of the Southern California Coastline: Long Beach to US/Mexico Border

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This lidar point data set collected during low tide conditions along an approximately 500-700 meter wide strip of the Southern California coastline within an area...

  1. September 2008 Scripps Institute of Oceanography (SIO) Lidar of the Southern California Coastline: Long Beach to US/Mexico Border

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This lidar point data set was collected during low tide conditions along an approximately 500-700 meter wide strip of the Southern California coastline within an...

  2. November 2007 Scripps Institute of Oceanography (SIO) Lidar of the Southern California Coastline: Long Beach to US/Mexico Border

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This lidar point data set was collected during low tide conditions along an approximately 500-700 meter wide strip of the Southern California coastline within an...

  3. March 2009 Scripps Institute of Oceanography (SIO) Lidar of the Southern California Coastline: Long Beach to US/Mexico Border

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This lidar point data set was collected during low tide conditions along an approximately 500-700 meter wide strip of the Southern California coastline within an...

  4. Estructura temporal y espacial de la comunidad de peces arrecifales de la Isla San Jose, Golfo de California, Mexico

    National Research Council Canada - National Science Library

    Barjau, Emelio; Rodriguez-Romero, Jesus; Galvan, Felipe; Gutierrez, Francisco; Lopez, Juana

    2012-01-01

    Para determinar la variacion estacional y espacial de la comunidad de peces en ocho localidades alrededor de la Isla San Jose en el Golfo de California se realizo un estudio ecologico de marzo 2001 a febrero 2002...

  5. Primary colonization and breakdown of igneous rocks by endemic, succulent elephant trees (Pachycormus discolor) of the deserts in Baja California, Mexico.

    Science.gov (United States)

    Bashan, Yoav; Vierheilig, Horst; Salazar, Bernardo G; de-Bashan, Luz E

    2006-07-01

    Trees growing in rocks without soil are uncommon. In two arid regions in Baja California, Mexico, field surveys found large numbers of rock-colonizing elephant trees (Pachycormus discolor (Benth.) Coville ex Standl. (Mexican name: copalquin) growing in igneous rocks (granite and basalt) as primary colonizers without the benefit of soil or with a very small amount of soil generated by their own growth. Many adult trees broke large granite boulders and were capable of wedging, growing in, and colonizing rocks and cliffs made of ancient lava flows. This is the first record of a tree species, apart from the previously recorded cacti, capable of primary colonization of rocks and rock rubble in hot deserts.

  6. A multi-trial diagnostic tool in fin whale (Balaenoptera physalus) skin biopsies of the Pelagos Sanctuary (Mediterranean Sea) and the Gulf of California (Mexico).

    Science.gov (United States)

    Fossi, Maria Cristina; Urban, Jorge; Casini, Silvia; Maltese, Silvia; Spinsanti, Giacomo; Panti, Cristina; Porcelloni, Serena; Panigada, Simone; Lauriano, Giancarlo; Niño-Torres, Carlos; Rojas-Bracho, Lorenzo; Jimenez, Begoña; Muñoz-Arnanz, Juan; Marsili, Letizia

    2010-01-01

    The main objective of this study was to apply a set of sensitive non-lethal biomarkers in skin biopsies of fin whales (Balaenoptera physalus) to evaluate the toxicological status of this mysticete in the Pelagos Sanctuary (Mediterranean Sea) and in the Gulf of California (Sea of Cortez-Mexico). We developed a "multi-trial diagnostic tool" (based on field and in vitro studies), combining molecular biomarkers (western blot of CYP1A1, CYP2B) and gene expression (qRT-PCR of HSP70, ERα, AHR, E2F-1) with the analysis of OCs, PAHs and PBDEs. The study revealed a higher level of toxicological stress in the Mediterranean fin whales. Copyright © 2009 Elsevier Ltd. All rights reserved.

  7. Use of lead-glazed ceramic ware and lead-based folk remedies in a rural community of Baja California, Mexico.

    Science.gov (United States)

    Welton, Michael; Rodriguez-Lainz, Alfonso; Loza, Oralia; Brodine, Stephanie; Fraga, Miguel

    2016-06-14

    Lead exposure from lead-glazed ceramics (LGCs) and traditional folk remedies have been identified as significant sources of elevated blood lead levels in Mexico and the United States. This study took place from 2005 to 2012 in a rural community in Baja California, Mexico. 1) Investigate the knowledge, attitudes, and practices related to lead and lead exposures from LGCs and two lead-based folk remedies (azarcon and greta); and 2) evaluate a pilot intervention to provide alternative lead-safe cookware. A baseline household survey was conducted in 2005, followed by the pilot intervention in 2006, and follow-up surveys in 2007 and 2012. For the pilot intervention, families who reported using LGCs were given lead-safe alternative cookware to try and its acceptance was evaluated in the following year. The community was mostly of indigenous background from Oaxaca and a high proportion of households had young children. In 2006, all participants using traditional ceramic ware at the time (n = 48) accepted lead-safe alternative cookware to try, and 97% reported that they were willing to exchange traditional ceramic ware for lead-safe alternatives. The use of ceramic cookware decreased from over 90% during respondents' childhood household use in Oaxaca to 47% in 2006 among households in Baja California, and further reduced to 16.8% in 2012. While empacho, a folk illness, was widely recognized as an intestinal disorder, there was almost universal unfamiliarity with the use and knowledge of azarcon and greta for its treatment. This pilot evaluation provides evidence 1) for an effective and innovative strategy to reduce lead exposure from LGCs and 2) of the feasibility of substituting lead-free alternative cookware for traditional ceramic ware in a rural indigenous community, when delivered in a culturally appropriate manner with health education. This strategy could complement other approaches to reduce exposure to lead from LGCs. © The Author(s) 2016.

  8. Alcances y limitaciones de las políticas sobre el derecho a la no discriminación a escala subnacional en México: el caso de Baja California Sur

    Directory of Open Access Journals (Sweden)

    Gerardo ORDÓÑEZ-BARBA

    2012-01-01

    Full Text Available En este artículo se analiza la situación que guarda la instrumentación de las políticas del derecho a la no discriminación en una de las entidades que, al menos formalmente, se encuentra a la vanguardia en esta materia. Se trata de mostrar los alcances y limitaciones de la legislación de Baja California Sur que alude a los temas de la igualdad, ciudadanía, discriminación y protección a grupos vulnerables; así como de los programas, dependencias y recursos estatales que posibilitan la integración de personas y grupos que padecen discriminación, exclusión o violencia. En elestudio se constata que, a pesar de los avances legislativos, las iniciativas y los recursos involucrados en estas áreas de responsabilidad están aún lejos de ser un instrumento eficaz para el pleno ejercicio del derecho a la no discriminación de los sudcalifornianos.

  9. Relación entre las capturas de Megapitaria squalida (Bivalvia: Veneridae y la temperatura superficial del mar en la Bahía de la Paz, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Mariana Vázquez Hurtado

    2011-03-01

    Full Text Available La almeja chocolate Megapitaria squalida es un recurso pesquero con creciente importancia en el noroeste de México al registrarse un incremento en los volúmenes de captura. Sin embargo, esta pesquería ha observado variaciones importantes en las capturas que podrían estar relacionadas con factores ambientales. Se obtuvieron datos mensuales de producción de M. squalida durante 2002- 2005 y se estimaron series de tiempo de temperatura superficial del mar en la Bahía de La Paz B.C.S. a partir de imágenes mensuales derivadas del sensor MODIS-Aqua. Los resultados indican una relación positiva significativa entre la temperatura superficial del mar y los volúmenes de captura, razón por la cual nuestro trabajo tiene como objetivo estudiar las relaciones entre capturas de Megapitaria squalida (Bivalvia: Veneridae y la temperatura superficial del mar en La Bahía de la Paz, Baja California Sur, México.

  10. Experiencias de investigación geográfica en el estudio de la pesca comercial ribereña en las áreas naturales protegidas de Baja California Sur (México

    Directory of Open Access Journals (Sweden)

    José Manuel Crespo-Guerrero

    2016-08-01

    Full Text Available Cuando el geógrafo comienza a investigar un tema por primera vez, un torbellino de ideas barre su cabeza. Es una etapa de ansiedad en donde se plantea cómo encontrar la hebra con la que empezar a tejer. Pretendemos mostrar aquí cómo nos organizamos para el estudio de la pesca comercial ribereña practicada en las áreas naturales protegidas del estado de Baja California Sur (BCS. El trabajo de campo tiene como base la obtención de información, fruto de la interacción entre el geógrafo y la fuente. El conocimiento es el primer producto de la experiencia propia y ajena. Las fuentes de información se emplazan en espacios diversos. Unas veces se localizan en archivos, bibliotecas, hemerotecas… en forma de legajos, monografías o publicaciones periódicas. Otras, en instituciones que recopilan información actualizada de naturaleza heterogénea (estadística, cartográfica, legal, iconográfica, etc..

  11. Response to exploitation (1982-2002) of the Los Azufres, Michoacan (Mexico) geothermal field. Part II: South Zone; Respuesta a la explotacion (1982-2003) del yacimiento geotermico de Los Azufres, Michoacan (Mexico). Parte II: Zona Sur

    Energy Technology Data Exchange (ETDEWEB)

    Arellano G, Victor Manuel [Instituto de Investigaciones Electricas, Cuernavaca, Morelos, (Mexico); Torres R, Marco Antonio [Comision Federal de Electricidad, Morelia, Michoacan (Mexico); Barragan R, Rosa Maria [Instituto de Investigaciones Electricas, Cuernavaca, Morelos, (Mexico); Sandoval M, Fernando [Comision Federal de Electricidad, Morelia, Michoacan (Mexico)

    2005-06-01

    The paper describes the thermodynamic evolution of fluids in the Los Azufres geothermal field's southern zone reservoir, as a response to exploitation from 1982 to 2002. Thermodynamic conditions for the reservoir fluids were estimated with production data using the WELFLO heat-and-flow well simulator. In the southern zone, initial fluid thermodynamic conditions indicated that compressed liquid, two-phase fluids and vapor occurred in the reservoir, depending on the well depths. The fist response to exploitation consisted in a pressure drop an enthalpy increase. For the long term, the following patterns have been identified: pressure and mass flow-rate drop, boiling, cooling, vapor production and in some wells affected by injection an increase in both pressure and mass flow rate. The isotopic results of well fluids in the southern zone showed the occurrence of two processes. The first, with a positive slope, indicates a mixing of reservoir and injection fluids and mainly affects wells Az-2, Az-16, Az-33, Az-36 and Az-46. The second, with a negative slope, results from the original processes of reservoir steam separation and partial condensation. [Spanish] En este trabajo se presenta un estudio sobre la evolucion termodinamica de los fluidos de la zona sur del yacimiento de Los Azufres, como respuesta a la extraccion e inyeccion de fluidos, desde el inicio de su explotacion en 1982 hasta el ano 2002. Las condiciones termodinamicas de los fluidos del yacimiento se estimaron mediante el simulador de flujo de fluidos y calor en pozos WELFLO, a partir de datos de produccion. Las condiciones termodinamicas iniciales de los fluidos de la zona sur, indicaron la existencia de liquido comprimido, dos fases con liquido dominante y dos fases con vapor dominante, dependiendo de la profundidad de los pozos. La respuesta inicial de la zona sur a la explotacion consistio en una disminucion de la presion y un aumento en la entalpia mientras que a mas largo plazo se han observado

  12. Deep-water bivalve mollusks collected during the TALUD XV cruise off the west coast of the southern Baja California Peninsula, Mexico.

    Science.gov (United States)

    Hendrickx, Michel E; Valentich-Scott, Paul; Suárez-Mozo, Nancy Yolimar

    2016-01-01

    During the TALUD XV research cruise off the southern part of the Baja California Peninsula, Mexico, samples of macro-invertebrates obtained in the deep-sea (296-2136 m) revealed a rich fauna of bivalves (17 species belonging to 10 families). The number of species per station varied from one to five. The richest families were Nuculidae, Nuculanidae, Neilonellidae, Limidae, and Cuspidariidae. Solemyidae, Lucinidae, Poromyidae, Verticordiidae, and Pectinidae were each represented by a single species. Some species groups need a thorough revision and were tentatively identified (Nuculana cf. hamata, Limatula cf. saturna). Significant new distribution information is provided for two species, both recorded for the first time from off western Mexico: Ennucula panamina with an extension of its known distribution over 20° of latitude north and Jupiteria callimene with an extension of 16° 42' of latitude to the north. One species (Ennucula taeniolata) is reported in shallower depth and one in deeper water (Acesta sphoni). New records are provided for an additional nine species. Environmental and habitat conditions are given for the first time for many of the bivalve species.

  13. Constraints on the rheology of the lower crust in a strike-slip plate boundary: evidence from the San Quintín xenoliths, Baja California, Mexico

    Science.gov (United States)

    van der Werf, Thomas; Chatzaras, Vasileios; Marcel Kriegsman, Leo; Kronenberg, Andreas; Tikoff, Basil; Drury, Martyn R.

    2017-12-01

    The rheology of lower crust and its transient behavior in active strike-slip plate boundaries remain poorly understood. To address this issue, we analyzed a suite of granulite and lherzolite xenoliths from the upper Pleistocene-Holocene San Quintín volcanic field of northern Baja California, Mexico. The San Quintín volcanic field is located 20 km east of the Baja California shear zone, which accommodates the relative movement between the Pacific plate and Baja California microplate. The development of a strong foliation in both the mafic granulites and lherzolites, suggests that a lithospheric-scale shear zone exists beneath the San Quintín volcanic field. Combining microstructural observations, geothermometry, and phase equilibria modeling, we estimated that crystal-plastic deformation took place at temperatures of 750-890 °C and pressures of 400-560 MPa, corresponding to 15-22 km depth. A hot crustal geotherm of 40 ° C km-1 is required to explain the estimated deformation conditions. Infrared spectroscopy shows that plagioclase in the mafic granulites is relatively dry. Microstructures are interpreted to show that deformation in both the uppermost lower crust and upper mantle was accommodated by a combination of dislocation creep and grain-size-sensitive creep. Recrystallized grain size paleopiezometry yields low differential stresses of 12-33 and 17 MPa for plagioclase and olivine, respectively. The lower range of stresses (12-17 MPa) in the mafic granulite and lherzolite xenoliths is interpreted to be associated with transient deformation under decreasing stress conditions, following an event of stress increase. Using flow laws for dry plagioclase, we estimated a low viscosity of 1.1-1.3×1020 Pa ṡ s for the high temperature conditions (890 °C) in the lower crust. Significantly lower viscosities in the range of 1016-1019 Pa ṡ s, were estimated using flow laws for wet plagioclase. The shallow upper mantle has a low viscosity of 5.7×1019 Pa ṡ s

  14. Trace metals in sediments and Zostera marina of San Ignacio and Ojo de Liebre lagoons in the central pacific coast of Baja California, Mexico.

    Science.gov (United States)

    Macías-Zamora, J V; Sánchez-Osorio, J L; Ríos-Mendoza, L M; Ramírez-Alvarez, N; Huerta-Díaz, M A; López-Sánchez, D

    2008-08-01

    San Ignacio and Ojo de Liebre lagoons in central Baja California, Mexico are nursery and grazing grounds for whales and turtles. Ojo de Liebre Lagoon also supports a salt mine operation. By concentrating trace metals via evaporation, this activity might harm biota. Consequently, salt mining might be incompatible with the lagoon's ecological role. Eelgrass can incorporate these elements and reroute them to other organisms. Trace metals in sediments (Cd, Co, Cu, Mn, Ni, Pb, Zn, and Fe) were measured at both lagoons. Some (Cu, Mn, Pb, and Zn) were also measured in Zostera marina patches at both lagoons. The results did not show elevated metal concentration at any lagoon, either for sediments or eelgrass. No statistically significant differences between lagoons were found. However, eelgrass at both lagoons showed larger concentration ranges than in sediments. Also, a correlation exists between sediment metal concentration and its concentration in eelgrass. Surprisingly, several sediment metal concentrations are higher than those considered as elevated for the Southern California Bight.

  15. Condicionantes del turismo sustentable en el caribe mexicano Conditions of sustainable tourism on the Caribbean coast of Mexico Les conditions du tourisme soutenable sur la côté caribéenne du Mexique.

    Directory of Open Access Journals (Sweden)

    Rosalía Gómez Uzeta

    2011-09-01

    Full Text Available La concurrence internationale sur le marché touristique a des effets négative sur le comportement des flux touristiques américains sur les rivages caribéens du Mexique. La massification des flux a mis en évidence les limites du modèle traditionnel basé sur l'offre « soleil et plage  » commune à l’ensemble de l’espace carïbéen. Pour cette raison, il est nécessaire de repenser de nouvelles façons de soutenir le développement du tourisme, de la décentralisation des fonctions politiques et administratives des trois paliers de gouvernement, et de chercher à renforcer les synergies régionales pour renforcer les possibilités de diversification du développement autour de nouvelles attractions et offres provenant des marchés locaux.Cette stratégie permettra de promouvoir la durabilité de l'économie régionale et d'État et de consolider un projet de développement viable à long terme.The competition on the international tourism market has negative effects on the behavior of American’ tourist flows on the Caribbean coast of Mexico. The mass flows has highlighted the limitations of traditional model based on the offer "sun and beach" common throughout the Caribbean area. For this reason, we need to rethink new ways to support development tourism, the decentralization of political and administrative functions of the three levels of government, and seek to strengthen regional synergies to enhance diversification opportunities around the development of new attractions and offers from local markets.This strategy will promote the sustainability of the regional economy and state and consolidate a sustainable development project in the long term.Existen condiciones de competencia internacional que han afectado negativamente el comportamiento del flujo turístico norteamericano al Caribe Mexicano, ello ha puesto en evidencia la vulnerabilidad del modelo tradicional basado en la oferta de “sol y playa”, que se ha agrava en la

  16. Methodology to determine the consumption and potential of saving of electrical energy in the systems of air-conditioning in the residential sector: case the Northwest of Mexico; Metodologia para determinar el consumo y potencial de ahorro de energia electrica en los sistemas de climatizacion en el sector residencial: caso Noroeste de Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Rosas Flores, J. A.; Morillon Galvez, D.

    2008-07-01

    In this work there are studied the characteristics of the consumption of electrical residential energy due to the systems of air conditioning and to cos mell, in the region Northwest of Mexico (Sonora, Sinaloa, Baja California Norte, Baja California Sur, and Nayarit) and the North region (Coahuila, Chihuahua, Durango, Nuevo Leon). Between the principal results one finds that the potential saving of electrical energy, with base in the use of passive systems as the isolation of the housings, decided in 3,356 GWh (similar to the electrical annual supply that there needs the state of Durango or Guerrero). (Author)

  17. Changes in Structure and Diversity of Woody Plants in a Secondary Mixed Pine-Oak Forest in the Sierra Madre del Sur of Mexico

    Directory of Open Access Journals (Sweden)

    Roberto Carlos Almazán-Núñez

    2016-04-01

    Full Text Available The biotic province of the Sierra Madre del Sur presents a mosaic of woodlands at different successional stages due to frequent modifications in land use. In this study, we analyzed changes in woody flora across three successional stages of pine-oak forest: early, intermediate, and mature. Vegetation composition and diversity were characterized in 10 plots (each 0.28 ha. The mature stage had the highest values for species richness, abundance, and diversity. Pioneer plants were dominant in the early-successional site and may promote the establishment of late-successional species. The vegetation structure was more complex in the mature stage, where members of the Quercus genus were co-dominant with Pinus species. Pine tree richness was highest in the early-successional stage, and its abundance increased at the intermediate-successional site. These results suggest that Pinus species can grow in perturbed and sunny environments but also require favorable edaphic and microclimatic conditions, such as those found in intermediate woodlands. Results of this fieldwork support the initial floristic composition succession model, which suggests that species present at early stages will also occur in subsequent stages. Ecological succession may be considered to be a natural restoration process, and thus, conservation strategies should focus on maintaining distinct successional communities in addition to mature forests in order to preserve a high number of species.

  18. [Asthma mortality trends in Mexico].

    Science.gov (United States)

    Salas Ramírez, M; Segura Méndez, N H; Martínez-Cairo Cueto, S

    1994-04-01

    The objective of this cross-sectional study was to estimate mortality and morbidity from asthma in Mexico by federative entity (state) of residence, age, and sex during the period between 1960 and 1988. Statistics published by the National Institute of Statistics, Geography, and Information Science were reviewed, as were vital statistics and information from other sources. Data were selected on mortality, hospital admissions, and outpatient visits, as well as population by federative entity, age, and sex. Mortality and morbidity rates were adjusted for age using the direct method. From 1960 to 1987, mortality decreased for both sexes. The groups with the highest asthma mortality were those under 4 years of age and those over 50. From 1960 to the present, the state with the highest mortality was Tlaxcala. Hospitalizations increased from 10 to 140 per 100,000 population for the country as a whole. When both outpatient visits and hospitalizations were considered, the morbidity rates rose from 180 to 203.4 per 100,000 between 1960 and 1970. In 1970, hospital morbidity was higher among males than females. From 1960 up to the 1990s, the highest rates of hospitalization and outpatient visits were registered among those under 4 and those over 60. The states with the highest asthma hospitalization rates were Morelos, Baja California Sur, Nuevo León, Durango, and Tamaulipas. It is concluded that asthma mortality in Mexico is showing a downward trend, while morbidity is increasing considerably, especially among adolescents.

  19. Volcanic Markers of the Post-Subduction Evolution of Baja California and Sonora, Mexico: Slab Tearing Versus Lithospheric Rupture of the Gulf of California

    Science.gov (United States)

    Calmus, Thierry; Pallares, Carlos; Maury, René C.; Aguillón-Robles, Alfredo; Bellon, Hervé; Benoit, Mathieu; Michaud, François

    2011-08-01

    The study of the geochemical compositions and K-Ar or Ar-Ar ages of ca. 350 Neogene and Quaternary lavas from Baja California, the Gulf of California and Sonora allows us to discuss the nature of their mantle or crustal sources, the conditions of their melting and the tectonic regime prevailing during their genesis and emplacement. Nine petrographic/geochemical groups are distinguished: "regular" calc-alkaline lavas; adakites; magnesian andesites and related basalts and basaltic andesites; niobium-enriched basalts; alkali basalts and trachybasalts; oceanic (MORB-type) basalts; tholeiitic/transitional basalts and basaltic andesites; peralkaline rhyolites (comendites); and icelandites. We show that the spatial and temporal distribution of these lava types provides constraints on their sources and the geodynamic setting controlling their partial melting. Three successive stages are distinguished. Between 23 and 13 Ma, calc-alkaline lavas linked to the subduction of the Pacific-Farallon plate formed the Comondú and central coast of the Sonora volcanic arc. In the extensional domain of western Sonora, lithospheric mantle-derived tholeiitic to transitional basalts and basaltic andesites were emplaced within the southern extension of the Basin and Range province. The end of the Farallon subduction was marked by the emplacement of much more complex Middle to Late Miocene volcanic associations, between 13 and 7 Ma. Calc-alkaline activity became sporadic and was replaced by unusual post-subduction magma types including adakites, niobium-enriched basalts, magnesian andesites, comendites and icelandites. The spatial and temporal distribution of these lavas is consistent with the development of a slab tear, evolving into a 200-km-wide slab window sub-parallel to the trench, and extending from the Pacific coast of Baja California to coastal Sonora. Tholeiitic, transitional and alkali basalts of subslab origin ascended through this window, and adakites derived from the partial

  20. Perros ferales en la isla de Cedros, Baja California, México: una posible amenaza para los pinnípedos Feral dogs at Isla de Cedros, Baja California, Mexico: a possible threat for pinnipeds

    Directory of Open Access Journals (Sweden)

    María Concepción García-Aguilar

    2012-09-01

    Full Text Available La presencia de perros ferales (Canis lupus familiaris en la isla de Cedros, Baja California, México, fue documentada hace más de 15 años. En el verano de 2009 e invierno 2009/2010, se realizaron 2 campañas de muestreo en la costa noreste de la isla para evaluar los hábitos alimentarios de los perros en las cercanías de las zonas de reproducción y descanso del lobo marino de California (Zalophus californianus y del elefante marino del norte (Mirounga angustirostris. Los mamíferos constituyeron el grupo consumido más importante en la alimentación de los perros (85.4%. Los resultados de este estudio muestran que en la costa noreste de la isla de Cedros los perros se alimentan de pinnípedos: el elefante marino fue la especie que más se consumió, con el mayor porcentaje en ambas temporadas (43.3% en verano y 51.9% en invierno; el lobo marino, fue la segunda durante el verano (23.3%, aunque su porcentaje disminuyó en el invierno (5.8%. Además del potencial impacto que el consumo por los perros pueda tener sobre las poblaciones de los pinnípedos, una amenaza adicional es la posible transmisión de los patógenos caninos, con serias consecuencias epizoóticas.The presence of feral dogs (Canis lupus familiaris in Isla de Cedros, Baja California, Mexico, has been documented for over 15 years. In the summer of2009 and the winter of 2009/2010, 2 sampling surveys were conducted in the northeast coastal portion of the island to assess the diet of feral dogs in the vicinity of hauled out California sea lions (Zalophus californianus and northern elephant seals (Mirounga angustirostris. Mammals were the most important prey group in the diet of dogs (85.4%. Our results show that in the northeast coast of Isla de Cedros, feral dogs feed on pinnipeds: the elephant seal was the most important prey in both seasons (43.3% in summer and 51.9% in winter, followed by the sea lion as the second most important prey during the summer (23.3%, while its

  1. Prevalence and Correlates of Heroin-Methamphetamine Co-Injection Among Persons Who Inject Drugs in San Diego, California, and Tijuana, Baja California, Mexico.

    Science.gov (United States)

    Meacham, Meredith C; Strathdee, Steffanie A; Rangel, Gudelia; Armenta, Richard F; Gaines, Tommi L; Garfein, Richard S

    2016-09-01

    Although persons who inject drugs (PWID) in the western United States-Mexico border region are known to inject both heroin and methamphetamine, little is known about the prevalence and risks associated with co-injection of this depressant-stimulant combination (also known as "goofball" and "Mexican speedball"). Baseline data from parallel cohort studies of PWID conducted concurrently in San Diego, CA, and Tijuana, Mexico, were used to estimate the prevalence and identify correlates of heroin-methamphetamine co-injection. PWID older than 18 years of age who reported injecting illicit drugs in the past month (N = 1,311; 32.7% female) were recruited in San Diego (n = 576) and Tijuana (n = 735) and completed interviewer-administered questionnaires. Bivariate and multivariable logistic regression analyses were used to identify correlates of heroin-meth-amphetamine co-injection. The prevalence of co-injection in the past 6 months was 39.9% overall and was higher in Tijuana (55.8%) than in San Diego (19.8%). In multivariable analyses adjusting for study cohort, distributive syringe sharing, purchasing syringes prefilled with drugs, finding it hard to get new syringes, reporting great or urgent need for treatment, and younger age were independently associated with co-injection. Past-6-month overdose was significantly associated with higher odds of co-injection in San Diego than in Tijuana. These findings indicate that heroin-methamphetamine co-injection is more common in Tijuana than in San Diego, yet this practice was only associated with overdose in San Diego. Heroin-methamphetamine coinjection was also independently associated with HIV-associated injection risk behaviors. Overdose-prevention interventions should address co-injection of depressants and stimulants.

  2. [Habitat use patterns of the Black Brant Branta bernicla nigricans (Anseriformes: Anatidae) in natural and artificial areas of Guerrero Negro, Baja California Sur, Mexico].

    Science.gov (United States)

    Cedillo, Israel Martínez; Carmona, Roberto; Ward, David H; Danemann, Gustavo D

    2013-06-01

    The Black Brant is a common inhabitant of the Western Artic American tundra, which migrates to Southern Pacific coasts during the winter season. Approximately, 31000 birds (31%) constitute the Mexican population of Brants at Guerrero Negro, Ojo de Liebre, and Exportadora de Sal lagoon complex; nevertheless, there is little information about the distribution patterns and zone usage. At Guerrero Negro Lagoon (GNL), Ojo de Liebre Lagoon (OLL, both natural sites), and at Exportadora de Sal (ESSA, artificial site) we determined by monthly censuses (from November 2006 to April 2007, 08:00-16:00h) and observed: (1) season and site effects on population structure (age groups), and (2) the tide level relationship with the abundance and proportion of feeding birds. Within a total of 150 observation hours and 98 birds, our results showed a general 0.68 proportion of adults, that was higher in winter than in spring. The statistics analysis showed no effects by site on the proportion of feeding birds, but we observed a temporal decrease at ESSA and at GNL. In contrast the proportion of feeding birds at OLL was constant. We observed an increase in the juveniles between winter and spring. This increase is related with the differential migration, which mentions that the juveniles are the last to leave the wintering area. In winter the relations of the tide level with the abundance of Brant were: direct at ESSA, inverse at OLL and no relation found at GNL. In spring, no relation was observed in the sites. The proportion of Brants feeding at OLL (the site with the higher abundance) was independent of the tide level. This is related with two possible behaviors of the geese: (1) they can move through the lagoon and take advantage of the tidal lag, which is up to four hours; and (2) they can modify their feeding strategies, more on floating eelgrass (Zostera marina).

  3. Relationship between self-reported fish and shellfish consumption, carbon and nitrogen stable isotope values and total mercury concentrations in pregnant women (II from Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Rebecca Bentzen

    2014-01-01

    Full Text Available Seafood is a valuable source of nutrients important for fetal development. However, seafood consumption is the main route of exposure to monomethyl mercury (MeHg+ for humans. MeHg+ is highly bioavailable and potentially adversely affects fetal neurodevelopment. MeHg+ exposure from fish consumption varies significantly by age and trophic level of fish consumed as well as the frequency and amount of fish consumed. This study investigates total Hg concentrations ([THg] in hair segments of pregnant Mexican women in relation to (1 self-reported frequency of fish and shellfish consumption, (2 maternal trophic level and marine diet contributions, determined using hair carbon (C and nitrogen (N stable isotopes, and (3 relates [THg] to various hair advisory thresholds. We also examined whether variation in C and N isotope values is explained by self-reported frequency of fish and shellfish consumption. A significant proportion of hair samples had [THg] higher than suggested agency thresholds and, for women within the range of the various advisory thresholds (1–20 μg g−1, the specific statistic used and threshold applied are important considerations for assessing and communicating risk. Individuals enriched in 15N (δ15N values had higher [THg] as did individuals that reported consuming fish and shellfish more frequently, suggesting that variation in [THg] can be explained by both consumer reported diet and diet as determined by C and N stable isotope assessment. However, at higher reported fish consumption levels the trophic level is maintained while [THg] is paradoxically lower. This suggests that THg exposure and assimilation are more complicated in higher fish frequency consumption categories. [THg] is more variable at the higher concentrations, possibly indicating some exposure to non-dietary Hg, heritable variations affecting Hg toxicodynamics, and BMI and tobacco exposure factors as outlined in our companion paper.

  4. Biomagnification of mercury and selenium in Blue Shark Prionace glauca from the Pacific Ocean off Mexico

    OpenAIRE

    Escobar-Sánchez, Ofelia; Galván Magaña, Felipe; Rosíles-Martínez, René

    2011-01-01

    The aim of this study was to determine the biomagnification of mercury through the principal prey of the blue shark, Prionace glauca, off the western coast of Baja California Sur, Mexico, as well as the relationship between mercury and selenium in blue sharks. High levels of mercury were found in shark muscle tissues (1.39±1.58 μg/g wet weight); these values are above the allowed 1.0 μg/g for human consumption. The Mercury to selenium molar ratio was 1:0.2. We found a low correlation between ...

  5. [Size and age structure of the striped marlin Tetrapturus audax (Pisces: Xiphidae), at Cabo San Lucas, Baja California sur, México].

    Science.gov (United States)

    Barrera, Felipe Neri Melo; Uraga, Roberto Felix

    2004-12-01

    The striped marlin (Tetrapturus audax) is found in temperate and tropical waters of the Pacific and Indian Ocean. It is particularly abundant in the southern tip of the Baja California peninsula. Specimens brought to Cabo San Lucas port (22 degrees 53' N y 109 degrees 54' W) by the sport fishery fleet that operates withing a radius of 54 km from 1988 to 1993 were sexes, measured and weighed. A total 1030 individuals were sampled. Dorsal fin spines (389) were collected for age estimation. The spines were sectioned and hyaline-opaque bands counted. The relation of length to spine radius was similar for males and females. The fourth dorsal spine reflected the growth of the fish. The rhythm of growth mark formation is yearly and related to the sea surface temperature. Ten age groups were found and the seventh group was the most abundant, followed by groups "6" and "8". The age structure of the striped marlin was stable in the study period. The observed sizes were 160-280 cm jaw length with 90% of the organisms measuring between 190 and 225 cm. The small individuals recruit to the fishery from June to December.

  6. Reproductive parameters of the southern stingray Dasyatis americana in southern gulf of Mexico Parámetros reproductivos de la raya látigo americana Dasyatis americana en el sur del golfo de México

    Directory of Open Access Journals (Sweden)

    Edith Ramírez-Mosqueda

    2012-07-01

    Full Text Available The southern stingray Dasyatis americana (Hildebrand & Schroeder, 1928 is the most landed elasmobranch by small-scale fleets in southern gulf of Mexico. However, little is known of its life history parameters in this region. In this study, a total of 900 specimens were collected from February 2006 to December 2008 to determine the reproductive parameters needed for population assessments by means of ecological risk assessments or demographic analysis. Results suggested that females of D. americana reproduce annually, with a gestation of 7-8 months. The reproductive cycle of females is asynchronous, with ovulation and parturition occurring throughout the year. Females and males matured at 764 and 517 mm disc width (DW50 respectively. D. americana has one of the highest fecundity among dasyatids, from 2 to 7 embryos, with a sex ratio of embryos of 1:1. A linear relationship between maternal DW and fecundity was estimated, the larger females contain more embryos. The status of the population of D. americana is a cause of concern in the southern gulf of Mexico due to its high frequency of capture in artisanal fisheries and its apparently low biological productivity.La raya látigo americana Dasyatis americana (Hildebrand & Schroeder, 1928, conocida como balá en México, es el elasmobranquio más capturado y desembarcado por flotas artesanales en el sur del golfo de México. Sin embargo, se conoce poco de sus parámetros de historia de vida en esta región. En este estudio, fueron analizados 900 ejemplares entre febrero 2006 y diciembre 2008 para determinar los parámetros reproductivos necesarios para evaluaciones poblacionales por medio de análisis demográficos o evaluaciones de riesgo ecológico. Los resultados sugieren que las hembras de D. americana se reproducen anualmente, con una gestación de 7-8 meses aproximadamente. El ciclo reproductivo de las hembras es asincrónico, con la ovulación y alumbramiento ocurriendo a lo largo de todo el

  7. Capacidad de carga turÍstica como base para el manejo sustentable de actividades ecoturísticas en Unidades de Manejo Ambiental (UMA de Baja California Sur (BCS

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    Reyna Ibañez Pérez

    2016-01-01

    Full Text Available Existen zonas ejidales con UMA ́s, que desean incursionar en el turismo alternativo; tal es el caso del Nuevo Centro Poblacional Ejidal (NCPE, Ley Federal de Aguas Número 3, que se extiende a tres municipios de Baja California Sur (BCS, posee una UMA y se destaca por buscar opciones para reactivar su economía. En este trabajo se presentan los resultados de un estudio de Capacidad de Carga Turística (CCT, realizada en dos senderos de ese ejido, mediante la aplicación de la metodología de Cifuentes, que busca establecer el número máximo de visitas que puede recibir un área con base en sus condiciones físicas, biológicas y de manejo; cuya estimación, requirió de la revisión de censos de flora y fauna, de información geológica, climatológica, geográfica, ambiental, social, económica, turística, así como trabajo de campo. Los resultados indican que, en el NCPE, Ley Federal de Aguas Número 3, existen dos senderos con potencialidad turística para los cuales, se ha estimado una Capacidad de Carga Efectiva (CCE de 18 visitantes/día para el sendero del arroyo El Camarón y de 10 visitantes/día sendero del arroyo El Saucito. Las cifras anteriores, son un referente para el establecimiento de medidas de control de las visitas en ambos senderos

  8. Crecimiento económico, desarrollo sustentable y turismo: Una aproximación del posicionamiento de Baja California Sur (BCS en el Barómetro de Sustentabilidad

    Directory of Open Access Journals (Sweden)

    Reyna Ibáñez Pérez

    2011-01-01

    Full Text Available Uno de los mayores anhelos de toda sociedad es alcanzar un nivel económico elevado; otro es el de tener la oportunidad de disfrutar eternamente de los servicios proporcionados por la madre naturaleza. Sin embargo, las tendencias indican que se experimenta un deterioro importante en el ambiente, a la par, de una elevada concentración de pobreza. Esto, aunado a la dependencia que algunas entidades y países han desarrollado en relación a actividades -como la turística- se ha convertido en una de las preocupaciones centrales de los gobiernos, el establecer mediciones para determinar si las pautas de crecimiento y desarrollo, van acorde con el cuidado del ambiente y el bienestar de las personas. Por ello, dentro de este artículo se analizan la evolución del crecimiento económico y posicionamiento de Baja California Sur (BCS -un estado con importante actividad turística- en el Barómetro de Sustentabilidad. En la introducción, se aprecia la evolución del concepto de crecimiento y desarrollo, para continuar con la caracterización de la zona de estudio. Posteriormente, se detalla la metodología empleada. Enseguida, se estudia la situación actual del sector turístico en BCS y la evolución del crecimiento y desarrollo económico. En el análisis de resultados, se describen los factores que ubican a BCS en un nivel Medio de sustentabilidad. Finalmente, se presentan algunas reflexiones en relación a los retos que en materia de turismo, crecimiento económico, desarrollo sustentable afronta BCS.

  9. Mercury exposure among household users and nonusers of skin-lightening creams produced in Mexico - California and Virginia, 2010.

    Science.gov (United States)

    2012-01-20

    Mercury exposure has been reported among users of skin-lightening creams produced outside the United States but not among nonusers in their households. Mercury exposure can result in irreversible renal and central nervous system damage or death. In March 2010, coordinators of a health study notified members of a Mexican-American family in California with four study participants that they had elevated blood mercury levels and also notified the local health department, which in turn asked the California Department of Public Health (CDPH) to investigate. CDPH interviewed the four study participants and a fifth household member and identified unlabeled skin-lightening creams with mercury content measured at 2.0%-5.7% by weight as the likely source of mercury exposure. CDPH also interviewed friends of the study participants in California who had used similar skin-lightening products, and the Virginia Department of Health (VDH) interviewed relatives in that state who had used skin-lightening products. In all, investigators in the two states collected information and urine specimens for 22 persons in five households. The results indicated that 15 persons had elevated urinary mercury concentrations, including nine users of the cream (six with nonspecific symptoms) and six nonusers. Mercury vapor concentrations as high as 50 µg/m3 were measured in spot household locations; however, the overall concentration for each room in all five households was creams and issued clinical health alerts notifying physicians about this potential cause of mercury toxicity.

  10. Border Environmental Education Resource Guide: Southern New Mexico, South Texas, Northern Chihuahua, Northern Coahuila, Northern Nuevo Leon, Northern Tamaulipas = Guia de Recursos de Educacion Ambiental en la Frontera: Sur de Nuevo Mexico, Sur de Texas, Norte de Chihuahua, Norte de Coahuila, Norte de Nuevo Leon, Norte de Tamaulipas.

    Science.gov (United States)

    Meissner, David, Comp.

    This guide provides educators and residents of the border with useful information about environmental education program offerings along the eastern half of the United States-Mexico border. The programs listed in the guide represent a broad range of educational efforts focused on understanding the environment and solving environmental problems in…

  11. A checklist of helminth parasites of Elasmobranchii in Mexico.

    Science.gov (United States)

    Merlo-Serna, Aldo Iván; García-Prieto, Luis

    2016-01-01

    A comprehensive and updated summary of the literature and unpublished records contained in scientific collections on the helminth parasites of the elasmobranchs from Mexico is herein presented for the first time. At present, the helminth fauna associated with Elasmobranchii recorded in Mexico is composed of 132 (110 named species and 22 not assigned to species), which belong to 70 genera included in 27 families (plus 4 incertae sedis families of cestodes). These data represent 7.2% of the worldwide species richness. Platyhelminthes is the most widely represented, with 128 taxa: 94 of cestodes, 22 of monogeneans and 12 of trematodes; Nematoda and Annelida: Hirudinea are represented by only 2 taxa each. These records come from 54 localities, pertaining to 15 states; Baja California Sur (17 sampled localities) and Baja California (10), are the states with the highest species richness: 72 and 54 species, respectively. Up to now, 48 elasmobranch species have been recorded as hosts of helminths in Mexico; so, approximately 82% of sharks and 67% of rays distributed in Mexican waters lack helminthological studies. The present list provides the host, distribution (with geographical coordinates), site of infection, accession number in scientific collections, and references for the parasites. A host-parasite list is also provided.

  12. A checklist of helminth parasites of Elasmobranchii in Mexico

    Science.gov (United States)

    Merlo-Serna, Aldo Iván; García-Prieto, Luis

    2016-01-01

    Abstract A comprehensive and updated summary of the literature and unpublished records contained in scientific collections on the helminth parasites of the elasmobranchs from Mexico is herein presented for the first time. At present, the helminth fauna associated with Elasmobranchii recorded in Mexico is composed of 132 (110 named species and 22 not assigned to species), which belong to 70 genera included in 27 families (plus 4 incertae sedis families of cestodes). These data represent 7.2% of the worldwide species richness. Platyhelminthes is the most widely represented, with 128 taxa: 94 of cestodes, 22 of monogeneans and 12 of trematodes; Nematoda and Annelida: Hirudinea are represented by only 2 taxa each. These records come from 54 localities, pertaining to 15 states; Baja California Sur (17 sampled localities) and Baja California (10), are the states with the highest species richness: 72 and 54 species, respectively. Up to now, 48 elasmobranch species have been recorded as hosts of helminths in Mexico; so, approximately 82% of sharks and 67% of rays distributed in Mexican waters lack helminthological studies. The present list provides the host, distribution (with geographical coordinates), site of infection, accession number in scientific collections, and references for the parasites. A host-parasite list is also provided. PMID:27047240

  13. Latent classes of polydrug and polyroute use and associations with human immunodeficiency virus risk behaviours and overdose among people who inject drugs in Tijuana, Baja California, Mexico.

    Science.gov (United States)

    Meacham, Meredith C; Roesch, Scott C; Strathdee, Steffanie A; Lindsay, Suzanne; Gonzalez-Zuniga, Patricia; Gaines, Tommi L

    2017-03-24

    Patterns of polydrug use among people who inject drugs (PWID) may be differentially associated with overdose and unique human immunodeficiency virus (HIV) risk factors. Subgroups of PWID in Tijuana, Mexico, were identified based on substances used, route of administration, frequency of use and co-injection indicators. Participants were PWID residing in Tijuana age ≥18 years sampled from 2011 to 2012 who reported injecting an illicit substance in the past month (n = 735). Latent class analysis identified discrete classes of polydrug use characterised by 11 indicators of past 6 months substance use. Multinomial logistic regression examined class membership association with HIV risk behaviours, overdose and other covariates using an automated three-step procedure in mplus to account for classification error. Participants were classified into five subgroups. Two polydrug and polyroute classes were defined by use of multiple substances through several routes of administration and were primarily distinguished from each other by cocaine use (class 1: 5%) or no cocaine use (class 2: 29%). The other classes consisted primarily of injectors: cocaine, methamphetamine and heroin injection (class 3: 4%); methamphetamine and heroin injection (class 4: 10%); and heroin injection (class 5: 52%). Compared with the heroin-only injection class, memberships in the two polydrug and polyroute use classes were independently associated with both HIV injection and sexual risk behaviours. Substance use patterns among PWID in Tijuana are highly heterogeneous, and polydrug and polyroute users are a high-risk subgroup who may require more tailored prevention and treatment interventions. [Meacham MC, Roesch SC, Strathdee SA, Lindsay S, Gonzalez-Zuniga P, Gaines TL. Latent classes of polydrug and polyroute use and associations with human immunodeficiency virus risk behaviours and overdose among people who inject drugs in Tijuana, Baja California, Mexico. Drug Alcohol Rev 2017

  14. Continental rupture and the creation of new crust in the Salton Trough rift, Southern California and northern Mexico: Results from the Salton Seismic Imaging Project

    Science.gov (United States)

    Han, Liang; Hole, John A.; Stock, Joann M.; Fuis, Gary S.; Kell, Annie; Driscoll, Neal W.; Kent, Graham M.; Harding, Alistair J.; Rymer, Michael J.; González-Fernández, Antonio; Lázaro-Mancilla, Octavio

    2016-10-01

    A refraction and wide-angle reflection seismic profile along the axis of the Salton Trough, California and Mexico, was analyzed to constrain crustal and upper mantle seismic velocity structure during active continental rifting. From the northern Salton Sea to the southern Imperial Valley, the crust is 17-18 km thick and approximately one-dimensional. The transition at depth from Colorado River sediment to underlying crystalline rock is gradual and is not a depositional surface. The crystalline rock from 3 to 8 km depth is interpreted as sediment metamorphosed by high heat flow. Deeper felsic crystalline rock could be stretched preexisting crust or higher-grade metamorphosed sediment. The lower crust below 12 km depth is interpreted to be gabbro emplaced by rift-related magmatic intrusion by underplating. Low upper mantle velocity indicates high temperature and partial melting. Under the Coachella Valley, sediment thins to the north and the underlying crystalline rock is interpreted as granitic basement. Mafic rock does not exist at 12-18 km depth as it does to the south, and a weak reflection suggests Moho at 28 km depth. Structure in adjacent Mexico has slower midcrustal velocity, and rocks with mantle velocity must be much deeper than in the Imperial Valley. Slower velocity and thicker crust in the Coachella and Mexicali valleys define the rift zone between them to be >100 km wide in the direction of plate motion. North American lithosphere in the central Salton Trough has been rifted apart and is being replaced by new crust created by magmatism, sedimentation, and metamorphism.

  15. Childhood asthma along the United States/ Mexico border: hospitalizations and air quality in two California counties El asma infantil en la frontera mexicana-estadounidense: hospitalizaciones y calidad del aire ambiental en dos condados de California

    Directory of Open Access Journals (Sweden)

    Paul B English

    1998-06-01

    Full Text Available Since the passage of the North American Free Trade Agreement in 1993, there has been an increasing need to monitor environmental health trends that may be related to the rapid industrialization of the United States/Mexico border. We studied two counties on the California/Baja California border to obtain baseline data on trends in childhood asthma hospitalizations and two pollutants that aggravate asthma, ozone and particulate matter (less than 10 microns in diameter, from 1983 to 1994. Hospital discharge records of children 14 years and younger were analyzed, and rates by county, race, and sex were age-adjusted to the 1990 California population. Data on five ozone and particulate matter indices obtained from the California Environmental Protection Agency were used. Imperial County had the highest childhood asthma hospitalization rates in California for non-Hispanic whites and African-Americans, and the second highest for Hispanics. San Diego County had rates below the state average. Over the time period examined, rates in Imperial County increased 59%, while those in San Diego County decreased 9%. Maximum ozone levels increased 64% in Imperial County but decreased 46% in San Diego County. Particulate matter levels were four times higher in Imperial than in San Diego County. High rates of childhood asthma hospitalizations in Imperial County may be partially related to high levels of poverty and worsening air quality conditions produced by increased burdens on the local airshed. Asthma prevalence surveys and binational time-series analyses examining asthma-pollutant relationships are needed.Desde que se firmó el Tratado de Libre Comercio en 1993, ha aumentado la necesidad de monitorear problemas de salud que podrían relacionarse con la rápida industrialización de la frontera mexicana-estadounidense. Estudiamos dos condados de la fontera entre California y Baja California con objeto de obtener datos de base sobre las tendencias observadas de

  16. Seasonal variation of geostrophic velocity and heat flux at the entrance to the Gulf of California, Mexico

    Science.gov (United States)

    Mascarenhas, A. S.; Castro, Ruben; Collins, Curtis A.; Durazo, Reginaldo

    2004-07-01

    The divergence of the surface heat flux in the Gulf of California is driven by the exchange of waters with the Pacific Ocean [, 1994]. To estimate these exchanges, geostrophic velocities and heat fluxes were computed from nine sections of closely spaced conductivity-temperature-depth stations across the entrance to the Gulf of California between 1992 and 1999. The mean geostrophic velocity was composed of two alternating cores of inflow and outflow. The two cores that were adjacent to either coast were broader and contained the highest inflow (0.40 m/s) and outflow (-0.25 m/s) velocities, supporting the general idea of inflow along Sinaloa and outflow along Baja California (BC). During winter and spring the baroclinic outflow usually occurred near BC, and the baroclinic inflow occurred either through the center of the section and/or along the Sinaloa coast. Both inflow and outflow cores were ˜45 km wide and extended deeper than 700 dbar. Summer and fall showed a more complex pattern, with alternating cores of inflow and outflow but with inflow along Sinaloa on all cruises. During May the inflow was mainly in the center of the section, while outflow was concentrated along BC. The heat transport associated with the geostrophic flow was calculated and compared with estimates derived from surface heat budgets for the gulf [, 1994]. Both the geostrophic flow and heat transport exhibited (for the first empirical orthagonal function mode) a strong seasonal signal with the maximum amplitude in May and the minimum amplitude in late October. A seasonal fit to the net heat transport had an amplitude of 50 × 1012 W and phase of 133 days, in good agreement with other authors, further validating the geostrophic velocity estimates. The heat added to (subtracted from) the Pacific Ocean accelerates (decelerates) alongshore currents and appears to propagate ˜10° westward as a Rossby wave.

  17. Hydrochemical-isotopic and hydrogeological conceptual model of the Las Tres Vı´rgenes geothermal field, Baja California Sur, México

    Science.gov (United States)

    Portugal, E.; Birkle, P.; Barragán R, R. M.; Arellano G, V. M.; Tello, E.; Tello, M.

    2000-09-01

    from the Gulf of California in the deep reservoir. Both conditions indicate recharge of the reservoir by meteoric water during glacial periods in Holocene or Pleistocene time, or a magmatic origin of the reservoir fluids. The slightly positive slope of the δ18O-δD line of geothermal fluids and its intermediate isotopic composition-between the surface samples and magmatic (;andesitic;) water indicate that magmatic (;andesitic;) water contributes approximately 30% to the geothermal fluid composition, whereas ;fossil; meteoric water represents the major component (70%). The geothermal reservoir is considered to represent a hydrostatic, stagnant flow system. Based on the observed linear correlation between the isotopic composition and the altitude of the surface manifestations, the isotopic composition and altitude of the former recharge were determined as δ18O=-9.7‰ and δD=-67.3‰, and 350 m.a.s.l., respectively. This altitude is interpreted as mean (average) recharge elevation. Scarcity of permanent rivers, low density of springs and domestic wells, as well as low precipitation rates, reflect restricted distribution of shallow groundwater systems in the study zone. These systems are related to isolated, local aquifers composed of valley fillings.

  18. Teledermatology in Tijuana, Mexico.

    Science.gov (United States)

    Brown, Megan

    2016-12-01

    The Health Frontiers in Tijuana (HFiT) clinic is a binational partnership between the University of California, San Diego School of Medicine (San Diego, California); the Universidad Autónoma de Baja California School of Medicine (Tijuana, Mexico); and Desayunador Salesiano Padre Chava, a community grassroots organization in Tijuana, Mexico. Health Frontiers in Tijuana provides accessible quality health care for the underserved in Tijuana's Zona Norte. This article is a narrative meant to share my clinical experience as a dermatology resident who worked with HFiT to establish teledermatology services at this clinic.

  19. Efecto de la variabilidad ambiental en el reclutamiento y modelación bioeconómica en la pesquería de sardina del Pacífico (Sardinopssagax caerulea) de Bahía Magdalena, Baja California Sur, México

    OpenAIRE

    de Anda-Montañez, Juan Antonio; Ramos-Rodríguez, Alejandro; Martínez-Aguilar, Susana

    2010-01-01

    La ecuación stock-reclutamiento de Ricker incorporándole el índice multivariado del ENSO(IME) como variable ambiental fue ajustada a datos de la pesquería de sardina (Sardinops sagax caerulea) de Bahía Magdalena, Baja California Sur, México. Esta ecuación fue incorporada a un modelo bioeconómico estructurado por edad. La incertidumbre fue considerada al incorporar la variabilidad ambiental, y se realizaron proyecciones de siete años de duración, que equivalen a una generación de sardina. En l...

  20. Biología y ecología del camarón del fango común Upogebia dawsoni (Crustacea: Thalassinoidea) del Manglar Requesón, Bahía Concepción y el Estero Río Mulege, Baja California Sur, México.

    OpenAIRE

    Leija- Tristán, Antonio; Sánchez-Vargas, Dora Patricia

    2016-01-01

    Some aspects on the biology of the mud shrimp. Upogebia dawsoni from the Requeson mangrove area, whithin Bahia Concepcion, and Mulege river estuary, Mulege (Baja California Sur, México) are described. Collections of U. dawsoni were done in January (winter), March (Spring) and July (Summer) in 1986 at Requeson, and in October (Fall) of 1985 and June (summer) of 1986, at Mulege. A total of 280 individuals were collected between 0.40 and 1.0 m in depth. Size, sex ratio, spawning period, egg numb...

  1. Provenance of Conglomerates within a Late Cretaceous Turbidite Channel System on the North American Margin: the Rosario Formation, Baja California, Mexico

    Science.gov (United States)

    Dos Santos, Thisiane; Kneller, Benjamin; Morton, Andrew; Armelenti, Garibaldi; Pantopoulos, George; De Ros, Luiz Fernando

    2017-04-01

    The Rosario Formation forms part of the Peninsular Ranges forearc basin complex, which crops out discontinuously along the Pacific coast of the Baja California Peninsula, Mexico. This study concerns the upper, deep marine part of the Rosario Formation , which includes several slope channel systems, one of these, the San Fernando channel systems consists of five channel complex sets (CCS1 to CCS5), each characterized by three filling stages. Stage I consists of predominantly clast­ and matrix-supported conglomerates, with subordinate medium to coarse grained sandstones. Stage II consists of units of clast-supported conglomerates with subordinate medium to coarse-grained sandstones, separated by mainly thinly-bedded turbidites (intercalation of thin beds of fine-grained sandstones and mudstones). Stage III consists mainly of hemipelagic mudstones. The main objective of this research is to determine source area and to compare the coarse fraction and finer fraction (fragments rocks. Bulk quantification indicates that the main provenance tectonic mode of the fine fraction of the conglomerates can be interpreted as dissected magmatic arc, with subordinate uplifted basement and recycled orogenic contributions. The preliminary conclusion is that the sedimentary supply to the Rosario Formation was mostly derived from volcanic and plutonic rocks of the Upper Peninsular Ranges Arc complex known as the Alisitos Arc, which follows the western margin of the Peninsular Ranges batholith, as well as from older magmatic arc, and from recycling of sedimentary/metasedimentary terrains.

  2. Biomonitoring with Micronuclei Test in Buccal Cells of Female Farmers and Children Exposed to Pesticides of Maneadero Agricultural Valley, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    Idalia Jazmin Castañeda-Yslas

    2016-01-01

    Full Text Available Feminization of the agricultural labor is common in Mexico; these women and their families are vulnerable to several health risks including genotoxicity. Previous papers have presented contradictory information with respect to indirect exposure to pesticides and DNA damage. We aimed to evaluate the genotoxic effect in buccal mucosa from female farmers and children, working in the agricultural valley of Maneadero, Baja California. Frequencies of micronucleated cells (MNc and nuclear abnormalities (NA in 2000 cells were obtained from the buccal mucosa of the study population (n=144, divided in four groups: (1 farmers (n=37, (2 unexposed (n=35, (3 farmers’ children (n=34, and (4 unexposed children (n=38. We compared frequencies of MNc and NA and fitted generalized linear models to investigate the interaction between these variables and exposition to pesticides. Differences were found between farmers and unexposed women in MNc (p<0.0001, CC (p=0.3376, and PN (p<0.0001. With respect to exposed children, we found higher significant frequencies in MNc (p<0.0001, LN (p<0.0001, CC (p<0.0001, and PN (p<0.004 when compared to unexposed children. Therefore working as a farmer is a risk for genotoxic damage; more importantly indirectly exposed children were found to have genotoxic damage, which is of concern, since it could aid in future disturbances of their health.

  3. Lack of knowledge about mother-to-child HIV transmission prevention in pregnant women at Tijuana General Hospital, Baja California, Mexico.

    Science.gov (United States)

    Becka, Chandra M; Chacón-Cruz, Enrique; Araneta, Maria Rosario; Viani, Rolando M

    2015-01-01

    The objective of this study was to identify determinants of human immunodeficiency virus (HIV) knowledge regarding mother-to-child transmission (MTCT) among pregnant women at Tijuana General Hospital, Baja California, Mexico. Between March and November 2003, patients from the prenatal care (n = 1294) and labor and delivery (L&D) units (n = 495) participated in a cross-sectional study to measure HIV knowledge. Less than one-third (30%) knew that HIV could be transmitted to a child during delivery, and 36% knew that HIV could be transmitted by breast-feeding. Only 27% knew that an MTCT could be prevented. Prenatal patients were more likely to know that MTCT was preventable (prenatal: 31% versus L&D 25%; P = .02). Logistic regression indicated that prenatal patients (odds ratio = 1.49, confidence interval 1.07-2.07) were more likely to know that HIV could be transmitted through breast-feeding. Overall, both groups had poor knowledge regarding MTCT of HIV. © The Author(s) 2014.

  4. Strain Localisation at Rift Segment Boundaries: An Example from the Bocana Transfer Zone in Central Baja California, Mexico

    Science.gov (United States)

    Seiler, C.; Gleadow, A. J.; Kohn, B. P.

    2012-12-01

    Rifts are commonly segmented into several hundred kilometre long zones of opposing upper-plate transport direction with boundaries defined by accommodation and transfer zones. A number of such rift segments have been recognized in the northern Gulf of California, a youthful oceanic basin that is currently undergoing the rift-drift transition. However, detailed field studies have so far failed to identify suitable structures that could accommodate the obvious deformation gradients between different rift segments, and the nature of strain transfer at segment boundaries remains enigmatic. The situation is even less clear in central and southern Baja California, where a number of rift segments have been hypothesized but it is unknown whether the intervening segment boundaries facilitate true reversals in the upper-plate transport direction, or whether they simply accommodate differences in the timing, style or magnitude of deformation. The Bocana transfer zone (BTZ) in central Baja California is a linear, WNW-ESE striking structural discontinuity separating two rift segments with different magnitudes and styles of extensional deformation. North of the BTZ, the Libertad fault is part of the Main Gulf Escarpment, which represents the breakaway fault that separates the Gulf of California rift to the east from the relatively stable western portion of the Baja peninsula. The N-striking Libertad escarpment developed during the Late Miocene (~10-8Ma) and exhibits a topographic relief of ca. 1,000m along a strike-length of ca. 50km. Finite displacement decreases from ~1000m in the central fault segment to ~500m further south, where the fault bends SE and merges with the BTZ. In the hanging wall of the Libertad fault, a series of W-tilted horsts are bound along their eastern margins by two moderate-displacement E-dipping normal faults. South of the BTZ, extension was much less than further north, which explains the comparatively subdued relief and generally shallower tilt of

  5. Distribution, genetic structure, and conservation status of the rare microendemic species, Guaiacum unijugum (Zygophyllaceae in the Cape Region of Baja California, Mexico Distribución, estructura genética y conservación de la especie microendémica Guaiacum unijugum (Zygophyllaceae en la región de los Cabos de Baja California, México

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    Ross A. McCauley

    2010-12-01

    Full Text Available Guaiacum unijugum is a rare shrub endemic to a 70 km stretch of coastline extending east from San José del Cabo in Baja California and is the least well-known of the 4 species of Guaiacum in Mexico. To increase our knowledge of this species and assess its conservation status we surveyed the extent of occurrence using both herbarium material and field work, assessed levels of genetic diversity, determined its phylogenetic relationships, and completed an evaluation of risk of extinction (MER. Herbarium material identified 5 known localities of occurrence with field work verifying the continued persistence of 4 of these with an additional site discovered. Genetic analysis across the small range using 17 microsatellite loci showed very low levels of genetic diversity with a mean expected heterozygosity (H E of 0.162 over all polymorphic loci. Most loci were found to be monomorphic and genetic divergence was small, maintained by the presence of rare private alleles in widely-separated populations. Phylogenetic analysis indicated a sister group relationship to G. coulteri along the Pacific coast suggesting vicariance for the origin and occurrence of G. unijugum. The unique evolutionary history coupled with current small population sizes warrants increased conservation via listing as a critically endangered species.Guaiacum unijugum es un arbusto endémico en un área de aproximadamente 70 km en la región de Los Cabos, Baja California Sur, siendo la menos estudiada de las 4 especies de Guaiacum en México. Para incrementar nuestro conocimiento sobre esta especie y determinar su estatus de conservación se realizó un censo de sus poblaciones determinándose su estructura genética, su relación filogenética con otros miembros del género y se calculó su riesgo de extinción (MER. La revisión de material de herbario, confirmó la presencia de 4 poblaciones a las que se sumó el hallazgo de 1 más. Mediante el uso de 17 loci de microsatélites se

  6. Comparison of FRAX Scores of Southern California Females of Mexican Descent Using US Hispanic and Mexico Database

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    Keaton M. Nasser

    2011-01-01

    Results. The 10-year absolute risk of major osteoporotic fracture among women of Mexican descent using the US Hispanic database was 4.82 ± 5.03 (95% CI 3.97–5.67 compared to 4.86 ± 4.72 (CI 3.98–5.44 using the Mexico database (P=.94. The 10-year risk for hip fracture was 0.86 ± 1.78 (CI .56–1.16 compared to 1.12 ± 1.97 (CI .79–1.45, P=.26. The mean conformity for meeting the interventional threshold by either risk score was 94.8%. Conclusion. The comparison between the FRAX databases demonstrates a similarity in the absolute risk of major osteoporotic fracture. Differences are noted in the absolute number of hip fracture subjects at risk, but there is a high rate of conformity.

  7. Mafic Volcanism Along the Sinaloa Coast, Mexico, and its Relation to the Opening of the Gulf of California

    Science.gov (United States)

    Orozco Esquivel, T.; Ferrari, L.; Lopez Martinez, M.

    2007-05-01

    We report on new localities with mafic volcanism along the Sinaloa coast, which record changes in the magma generation processes along the eastern margin of the Gulf of California. South of Culiacán, Sinaloa, isolated outcrops of basaltic lavas built a ca. 60 km long belt aligned to the SE. The similarity in the mineralogy and composition of the lavas suggest that these outcrops could have been part of a single flow. Lavas contain abundant plagioclase (up to 3 mm), and olivine (up to 1.5 mm) phenocrysts, and scarce clinopyroxene, in a relatively coarse matrix. In multiement diagrams, the lavas show the negative Nb and Ta, and positive Pb and Sr anomalies characteristic of subduction related rocks. The age determination of these rocks is in process, nevertheless, rocks with similar compositions are known from ~11 Ma mafic dikes that outcrop in southern Sinaloa. The Pericos volcanic field, located about 25 km to the NW of Culiacán is composed by lava flows, shield volcanoes, and cinder cones of basaltic composition that cover an area of aprox. 20 x 32 km, and have a well preserved morphology suggestive of a Pliocene-Quaternary age. Lavas are porphyritic and contain olivine, plagioclase and clinopyroxene in a microcrystalline matrix. Some lava flows contain abundant megacrysts of green clinopyroxene (up to 8 cm), olivine (up to 1 cm), and/or plagioclase (up to 1 cm), or aggregates of olivine and clinopyroxene. Trace element abundances are remarkably uniform among all analyzed samples and are characteristic of intraplate magmas. Rocks with very similar composition, mineralogy, and also containing megacrysts, have been reported in the Pliocene Punta Piaxtla and Mesa Cacaxtla, located 200 km to the SSE at the Sinaloa coast. Those similarities indicate that mafic intraplate volcanism related to the opening of the Gulf of California is more broadly represented in the area than previously considered.

  8. Heavy metal levels in marine mollusks from areas with, or without, mining activities along the Gulf of California, Mexico.

    Science.gov (United States)

    Cadena-Cárdenas, Lázaro; Méndez-Rodríguez, Lía; Zenteno-Savín, Tania; García-Hernández, Jaqueline; Acosta-Vargas, Baudilio

    2009-07-01

    To assess the safety for human consumption of commercially important bivalves harvested from areas with or without mining activities, we compared the levels of heavy metals in mollusks collected from different coastal environments along the Gulf of California. We sampled the mussel Mytilus edulis and the clams Laevicardium elatum and Megapitaria squalida (June 2004) and the clam Chione californiensis (November 2006). Concentrations of cadmium, lead, nickel, zinc, iron, copper, and manganese in the soft tissue of the mollusks were measured by atomic absorption spectrophotometry. Based on dry weight, the highest average concentrations of iron, copper, and cadmium were found in clams from Loreto (572, 181, and 4.66 mg/kg, respectively); that of nickel, in mussels from San Luquitas (12.2 mg/kg); that of zinc, both in mussels from San Luquitas and in clams from Golfo de Santa Clara (94.3 and 91.8 mg/kg, respectively); and those of lead and manganese in clams from the Golfo de Santa Clara (9.2 and 3.68 mg/kg, respectively). Although mollusks were taken from coastal areas of the Gulf of California, which are considered to be contaminated by mining activities, the heavy metals in the sediments apparently were in a chemical form that had low bioavailability for the bivalves feeding in those areas. The interplay of oceanographic conditions and the chemical composition of anthropogenic inputs into the environment is not well understood. Thus, these factors or their interaction could potentially result in increased concentration and bioavailability of such metals in areas without effluent generated by mining activities.

  9. Composición química y precursores de ácidos vaccénico y ruménico en especies forrajeras en Baja California Sur, México

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    Eduardo Alberto Toyes-Vargas

    2013-01-01

    Full Text Available Los rumiantes pequeños que pastorean la vegetación nativa seleccionan su dieta a partir de una amplia variedad de especies vegetales, que difieren en su contenido y disponibilidad de nutrientes durante el año, y son fuente importante de nutrientes. El objetivo del estudio fue determinar y comparar la composición bioquímica de especies forrajeras asociadas al agostadero de Baja California Sur. Las especies evaluadas fueron huizache, mezquite, palo fierro, palo verde y vinorama, así como alfalfa henificada. Se cuantificó el contenido de materia seca, proteína cruda, lípidos totales, fibra cruda, cenizas, extracto libre de nitrógeno y energía bruta, así como la concentración de ácido linoléico, ácido -linolénico y ácidos grasos poliinsaturados ARA, EPA y DHA. Los resultados muestran que el palo verde y el mezquite presentaron un contenido mayor de proteína cruda. El huizache mostró la concentración mayor de lípidos totales, seguido de palo verde y mezquite. Huizache y alfalfa henificada presentaron las concentraciones mayores de ácido linoleico; mientras que palo verde alcanzó los niveles más altos de ácido alfa linolénico, seguido por palo fierro y alfalfa henificada. Palo verde, palo fierro y alfalfa henificada obtuvieron concentraciones mayores de ácidos grasos poliinsaturados. El uso de los forrajes de agostadero en la alimentación de los rumiantes es una alternativa que podrá modificar las proporciones de los ácidos grasos de la leche dado el contenido del ácido oleico, linoléico y linolénico, precursores del ácido vaccénico y ruménico y ácidos grasos poliinsaturados de la serie omega 3 como el EPA y el DHA.

  10. WATER TEMPERATURE, SALINITY, and HYDROSTATIC PRESSURE collected from R/V Point Sur in Entrance to the Gulf of California from 2013-04-19 to 2013-05-02 (NCEI Accession 0131072)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hydrographic data were collected in Pescadero Basin (at the entrance to the Gulf of California) and subsequently along the West Coast of Baja California and Southern...

  11. [Trophic ecology of the fish Arothron meleagris (Tetraodontiformes: Tetraodontidae) from Los Frailes reef, southern Baja California, Mexico].

    Science.gov (United States)

    Moreno, Xchel G; Abitia, L Andrés; Favila, Araceli; Gutiérrez, Francisco J; Palacios, Devis S

    2009-01-01

    Monthly samples were taken from November 2004 to October 2005 in the Los Frailes reef, BCS, Mexico. The objective was to determine the feeding habits of the pufferfish, Arothron meleagris, as well as possible variations in feeding patterns due to size and/or sex. We captured 101 specimens, with all stomachs contained food. The index of relative importance (IRI) was used to determine the main items; which were non-identified organic matter (NIOM) (30.44%), Echinometra vanbrunti (26.25 %), Porifera (12.63 %), Pocillopora spp. (11.84%), Bryozoa (5.37 %) and Porites spp. (4.83 %). Levin's index indicated a low trophic niche breadth (Bi=0.12) and allowed us to determine that A. meleagris is a specialist predator with strong preferences towards certain food types. The Morisita-Horn index showed a high trophic overlap between sexes (Clambda=0.78), seasons (hot and cold Clambda=0.95) and among sizes (small and medium Clambda=0.94; small and large Clambda=0.74; medium and large Clambda=0.83).

  12. The role of tropical cyclones on landscape dynamics in southern Baja California, Mexico based on Late Pleistocene-Holocene alluvial stratigraphy

    Science.gov (United States)

    McDonald, Eric; Antinao, Jose Luis; Rhodes, Edward J.; Brown, Nathan; Gosse, John

    2015-04-01

    Region-wide alluvial records provide evidence that time-transgressive changes in climate can be a major driver of landscape evolution. Historically, landfall of eastern Pacific tropical cyclones in southwestern North America during the late summer and early fall provide the strongest storms that have demonstrated geomorphic impact on the landscape. The alluvial fan record of the southern portion of Baja California (Mexico) was investigated to determine if linkages exist between region-wide fluvial deposits and tropical cyclones. The regional distribution and Pleistocene to Holocene morphostratigraphy of alluvial fans has been established for the southern portion of Baja California with primary focus on the La Paz and San José del Cabo basins. Six discrete morphopedosedimentary alluvial units (Qt1 through Qt6) were differentiated across the region using a combination of geomorphologic mapping, sedimentological analysis, and soil development further reinforced with geochronology using radiocarbon, optically stimulated luminescence and cosmogenic depth-profiles. A first phase of regional aggradation began before ~ 100 ka (Qt1) and culminated ~10 ka (Qt4). After deposition of Qt4, increasing regional incision of older units and the progressive development of a channelized alluvial landscape coincide with deposition of Qt5 and Qt6 units in a second, incisional phase. All units are conformed of multiple 1-3 m thick alluvial packages deposited in upper-flow regime and representing individual storms. Aggradational units (Qt1-Qt4) covered broad (>2 km) channels in the form of sheetflood deposition while incisional stage deposits are mostly confined to channels of ~0.5-2 km width. Continuous deposition of the thicker sequences is demonstrated by closely spaced luminescence dates in vertical profiles. In a few places disconformities between major units are evident and indicated by partly eroded buried soils. Analysis of historical terraces as part of the younger units

  13. Vegetation history along the eastern, desert escarpment of the Sierra San Pedro Mártir, Baja California, Mexico

    Science.gov (United States)

    Holmgren, Camille A.; Betancourt, Julio L.; Rylander, Kate A.

    2011-05-01

    Plant macrofossils from 38 packrat middens spanning the last ~ 33,000 cal yr BP record vegetation between ~ 650 and 900 m elevation along the eastern escarpment of the Sierra San Pedro Mártir, northern Baja California. The middens span most of the Holocene, with a gap between ~ 4600 and 1800 cal yr BP, but coverage in the Pleistocene is uneven with a larger hiatus between 23,100 and 14,400 cal yr BP. The midden flora is relatively stable from the Pleistocene to Holocene. Exceptions include Pinus californiarum, Juniperus californica and other chaparral elements that were most abundant > 23,100 cal yr BP and declined after 14,400 cal yr BP. Despite being near the chaparral/woodland-desertscrub ecotone during glacial times, the midden assemblages reflect none of the climatic reversals evident in the glacial or marine record, and this is corroborated by a nearby semi-continuous pollen stratigraphy from lake sediments. Regular appearance of C 4 grasses and summer-flowering annuals since 13,600 cal yr BP indicates occurrence of summer rainfall equivalent to modern (JAS average of ~ 80-90 mm). This casts doubt on the claim, based on temperature proxies from marine sediments in the Guaymas Basin, that monsoonal development in the northern Gulf and Arizona was delayed until after 6200 cal yr BP.

  14. Vegetation history along the eastern, desert escarpment of the Sierra San Pedro Mártir, Baja California, Mexico

    Science.gov (United States)

    Holmgren, Camille A.; Betancourt, Julio L.; Rylander, Kate A.

    2011-01-01

    Plant macrofossils from 38 packrat middens spanning the last ~ 33,000 cal yr BP record vegetation between ~ 650 and 900 m elevation along the eastern escarpment of the Sierra San Pedro Mártir, northern Baja California. The middens span most of the Holocene, with a gap between ~ 4600 and 1800 cal yr BP, but coverage in the Pleistocene is uneven with a larger hiatus between 23,100 and 14,400 cal yr BP. The midden flora is relatively stable from the Pleistocene to Holocene. Exceptions include Pinus californiarum, Juniperus californica and other chaparral elements that were most abundant > 23,100 cal yr BP and declined after 14,400 cal yr BP. Despite being near the chaparral/woodland-desertscrub ecotone during glacial times, the midden assemblages reflect none of the climatic reversals evident in the glacial or marine record, and this is corroborated by a nearby semi-continuous pollen stratigraphy from lake sediments. Regular appearance of C4 grasses and summer-flowering annuals since 13,600 cal yr BP indicates occurrence of summer rainfall equivalent to modern (JAS average of ~ 80–90 mm). This casts doubt on the claim, based on temperature proxies from marine sediments in the Guaymas Basin, that monsoonal development in the northern Gulf and Arizona was delayed until after 6200 cal yr BP.

  15. Bioaccumulation of trace metals in farmed pacific oysters Crassostrea gigas from SW Gulf of California coast, Mexico.

    Science.gov (United States)

    Jonathan, M P; Muñoz-Sevilla, N P; Góngora-Gómez, Andrés Martin; Luna Varela, Raquel Gabriela; Sujitha, S B; Escobedo-Urías, D C; Rodríguez-Espinosa, P F; Campos Villegas, Lorena Elizabeth

    2017-11-01

    The aim of the study was to evaluate the bioavailability of trace metals (Chromium, Copper, Nickel, Lead, Zinc, Cadmium, Arsenic, and Mercury) in the commercially consumed Crassostrea gigas oysters collected over a 12-month growth period (2011-12) from an experimental cultivation farm in La Pitahaya, Sinaloa State, Mexico. Sediment and water samples were also collected from four different zones adjacent to the cultivation area to identify the concentration patterns of metals. The results revealed that sewage disposals, fertilizers used for agricultural practices and shrimp culture are the major sources for the enrichment of certain toxic metals. The metal concentrations in oysters presented a decreasing order of abundance (all values in mg Kg-1): Zn (278.91 ± 93.03) > Cu (63.13 ± 31.72) > Cr (22.29 ± 30.23) > Cd (14.54 ± 4.28) > Ni (9.41 ± 11.33) > Pb (2.22 ± 1.33) > As (0.58 ± 0.91) > Hg (0.04 ± 0.06). Bioconcentration Factor (BCF) and Biota Sediment Accumulation Factor (BSAF) exhibited that C. gigas in the region are strong accumulators for Zn and Cd respectively. Thus, the present study proves to fulfill the gap in understanding the rate of bioaccumulation of metals in C. gigas which is regarded as the most sought after oyster species globally. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Impacts of using an ensemble Kalman filter on air quality simulations along the California-Mexico border region during Cal-Mex 2010 field campaign.

    Science.gov (United States)

    Bei, Naifang; Li, Guohui; Meng, Zhiyong; Weng, Yonghui; Zavala, Miguel; Molina, L T

    2014-11-15

    The purpose of this study is to investigate the impact of using an ensemble Kalman filter (EnKF) on air quality simulations in the California-Mexico border region on two days (May 30 and June 04, 2010) during Cal-Mex 2010. The uncertainties in ozone (O3) and aerosol simulations in the border area due to the meteorological initial uncertainties were examined through ensemble simulations. The ensemble spread of surface O3 averaged over the coastal region was less than 10ppb. The spreads in the nitrate and ammonium aerosols are substantial on both days, mostly caused by the large uncertainties in the surface temperature and humidity simulations. In general, the forecast initialized with the EnKF analysis (EnKF) improved the simulation of meteorological fields to some degree in the border region compared to the reference forecast initialized with NCEP analysis data (FCST) and the simulation with observation nudging (FDDA), which in turn leading to reasonable air quality simulations. The simulated surface O3 distributions by EnKF were consistently better than FCST and FDDA on both days. EnKF usually produced more reasonable simulations of nitrate and ammonium aerosols compared to the observations, but still have difficulties in improving the simulations of organic and sulfate aerosols. However, discrepancies between the EnKF simulations and the measurements were still considerably large, particularly for sulfate and organic aerosols, indicating that there are still ample rooms for improvement in the present data assimilation and/or the modeling systems. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Microfaunal evidence of age and depositional environments of the Cerro Prieto section (Plio-Pleistocene), Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ingle, J.C. Jr.

    1982-01-01

    Microfossils including benthic and planktic foraminifera, ostracodes, calcareous algae, fish skeletal material, and fragments of pelecypods were found in 14 core samples from depths of 185 to 1952 m in the Cerro Prieto geothermal field, providing evidence of both the age and depositional history of sediments comprising the 3000-m-thick Pliocene and Pleistocene section in this area. Ostracodes of brackish water and marine origin constitute the most common microfossils present in this sequence occurring in 8 samples; in situ littoral and neritic species of benthic foraminifera occur in 5 samples with planktic species present in 2 samples. Distributional patterns of ostracodes and foraminifera together with previously analyzed lithofacies (Lyons and van de Kamp, 1980) indicate that the Cerro Prieto section represents an intertonguing complex of alluvial, deltaic, estuarine, and shallow marine environments deposited along the front of the Colorado River delta as it prograded across the Salton Trough during Pliocene and Pleistocene time. Foraminiferal evidence indicates that a sand and shale unit commonly present at depths between 700 and 1100 m represents a significant mid-Pleistocene marine incursion in the Cerro Prieto area. Tentative correlation of the Cerro Prieto section with the well dated Palm Springs Formation of the Imperial Valley, California area suggests that the Pliocene/Pleistocene boundary occurs at a depth of approximately 2000 m in the area of well M-93. Reworked specimens of Cretaceous foraminifera and fragments of the Cretaceous pelecypod Inoceramus were found in five samples further substantiating the Colorado Plateau provenance of a significant portion of the Colorado River deltaic sediments in the Cerro Prieto area.

  18. The big sur ecoregion sudden oak death adaptive management project: ecological monitoring

    Science.gov (United States)

    Allison C. Wickland; Kerri M. Frangioso; David M. Rizzo; Ross K. Meentemeyer

    2008-01-01

    The Big Sur area is one of the most ecologically diverse regions in California. Land preservation efforts are well established in Big Sur, including numerous preserves, state parks and the Los Padres National Forest. However, there are still many conservation threats that cut across these areas including exotic species (plants, animals, and pathogens) and alterations...

  19. Hepatitis A: the burden among Latino children in California La hepatitis A: impacto entre los niños latinos californianos

    Directory of Open Access Journals (Sweden)

    David E. Hayes-Bautista

    2005-12-01

    Full Text Available OBJECTIVE: To determine the prevalence of Hepatitis A within subpopulations of southern California counties. MATERIAL AND METHODS: Age and race/ethnic-specific hepatitis A rates were derived from the California Department of Health Services Surveillance and Statistics Section for 1996-2001 and from demographic data of the California Department of Finance. RESULTS: 2.3 million Latino children (aged 0-14 years in five southern California counties had a rate of 31.1 cases per 100 000, five times higher than the non-Hispanic white rate. CONCLUSIONS: The CDC Advisory Committee on Immunization Practices recommends routine vaccination for children with "very high" rates of hepatitis A. The annual prevalence of hepatitis A in California, especially in southern California, met the CDC's "very high" definition, therefore Latino children in these counties should be considered for routine childhood hepatitis A vaccination. As health has no borders, this issue should be addressed by the public health services of both, the United States' and Mexico's public health services.OBJETIVO: Determinar la tasa de prevalencia de la hepatitis A entre ciertos grupos de población de los condados del sur de California. MATERIAL Y MÉTODOS: Se calcularon las tasas de hepatitis A por edad y raza/etnia utilizando los datos de los archivos del Centro de Servicios de Salud y Vigilancia de California, y los denominadores demográficos del ciclo 1996-2001 de la Sección de Estadísticas del Departamento de Finanzas de California. RESULTADOS: Los 2.3 millones de niños latinos (de 0 a 14 años de cinco condados del sur de California presentaron una tasa de 31.1 casos por cada 100 000 niños, lo que muestra que es cinco veces más alta que la tasa anglosajona. CONCLUSIONES: El Comité Consejero de Prácticas de Inmunización del CDC recomienda vacunar rutinariamente a los niños con índices "muy altos" de hepatitis A. La frecuencia anual de hepatitis A, especialmente en el sur de

  20. Two new species of Litobothrium Dailey, 1969 (Cestoda: Litobothriidea) from thresher sharks in the Gulf of California, Mexico, with redescriptions of two species in the genus.

    Science.gov (United States)

    Olson, P D; Caira, J N

    2001-03-01

    As part of a survey of the metazoan parasites of elasmobranchs of the Gulf of California, Mexico, the spiral intestines of 10 pelagic thresher sharks Alopias pelagicus and one bigeye thresher shark A. superciliosus were examined for tapeworms. Eight of the A. pelagicus specimens examined were found to host Litobothrium amplifica and L. daileyi. Both tapeworm species are redescribed based on examination of this new material with light and scanning electron microscopy, and the ranges of most of the measurements for these species are expanded; scanning electron micrographs and detailed illustrations and measurements of their segment anatomy are presented for the first time. An argument is made that the identification of the original host specimens of these species was in error and that A. pelagicus is likely to be the correct original host. In addition, L. nickoli n. sp., a third species in the genus hosted by A. pelagicus, was found in three of the 10 individual hosts examined. This species differs from all six known Litobothrium species in the form of the pseudosegments of the scolex, the anterior two being essentially non-cruciform, while the latter three are distinctly cruciform. All other species possess either no non-cruciform or at most one non-cruciform segment anteriorly. The single specimen of A. superciliosus examined was found to host the new species, L. janovyi. This species differs from L. coniformis, L. gracile and L. amsichensis in its possession of four rather than three, three and five cruciform pseudosegments, respectively. It lacks the modificiations of the fourth pseudosegment seen in L. amplifica and lacks the anterior non-cruciform fifth pseudosegment found in L. daileyi. It most closely resembles L. alopias but differs among other features in its greater total length, greater number of segments and longer mature segments. SEM of the four species collected from the Gulf of California as well as material of L. amsichensis from the goblin shark

  1. Neogene stratigraphy, foraminifera, diatoms, and depositional history of Maria Madre Island, Mexico: Evidence of early Neogene marine conditions in the southern Gulf of California

    Science.gov (United States)

    McCloy, C.; Ingle, J.C.; Barron, J.A.

    1988-01-01

    Foraminifera and diatoms have been analyzed from an upper Miocene through Pleistocene(?) sequence of marine sediments exposed on Maria Madre Island, largest of the Tre??s Marias Islands off the Pacific coast of Mexico. The Neogene stratigraphic sequence exposed on Maria Madre Island includes a mid-Miocene(?) non-marine and/or shallow marine sandstone unconformably overlain by a lower upper Miocene to uppermost Miocene upper to middle bathyal laminated and massive diatomite, mudstone, and siltstone unit. This unit is unconformably overlain by lower Pliocene middle to lower bathyal sandstones and siltstones which, in turn, are unconformably overlain by upper Pliocene through Pleistocene(?) upper bathyal to upper middle bathyal foraminiferal limestones and siltstones. These beds are unconformably capped by Pleistocene terrace deposits. Basement rocks on the island include Cretaceous granite and granodiorite, and Tertiary(?) andesites and rhyolites. The upper Miocene diatomaceous unit contains a low diversity foraminiferal fauna dominated by species of Bolivina indicating low oxygen conditions in the proto-Gulf Maria Madre basin. The diatomaceous unit grades into a mudstone that contains a latest Miocene upper to middle bathyal biofacies characterized by Baggina californica and Uvigerina hootsi along with displaced neritic taxa. An angular unconformity separates the upper Miocene middle bathyal sediments from overlying lower Pliocene siltstones and mudstones that contain a middle to lower bathyal biofacies and abundant planktonic species including Neogloboquadrina acostaensis and Pulleniatina primalis indicating an early Pliocene age. Significantly, this Pliocene unit contains common occurrences of benthic species restricted to Miocene sediments in California including Bulimina uvigerinaformis. Pliocene to Pleistocene(?) foraminiferal limestones and siltstones characterize submarine bank accumulations formed during uplift of the Tre??s Marias Island area, and include

  2. Are whale sharks exposed to persistent organic pollutants and plastic pollution in the Gulf of California (Mexico)? First ecotoxicological investigation using skin biopsies.

    Science.gov (United States)

    Fossi, Maria Cristina; Baini, Matteo; Panti, Cristina; Galli, Matteo; Jiménez, Begoña; Muñoz-Arnanz, Juan; Marsili, Letizia; Finoia, Maria Grazia; Ramírez-Macías, Dení

    2017-09-01

    The whale shark (Rhincodon typus) is an endangered species that may be exposed to micro- and macro-plastic ingestion as a result of their filter-feeding activity, particularly on the sea surface. In this pilot project we perform the first ecotoxicological investigation on whale sharks sampled in the Gulf of California exploring the potential interaction of this species with plastic debris (macro-, micro-plastics and related sorbed contaminants). Due to the difficulty in obtaining stranded specimens of this endangered species, an indirect approach, by skin biopsies was used for the evaluation of the whale shark ecotoxicological status. The levels of organochlorine compounds (PCBs, DDTs), polybrominated diphenyl ethers (PBDEs) plastic additives, and related biomarkers responses (CYP1A) were investigated for the first time in the whale shark. Twelve whale shark skin biopsy samples were collected in January 2014 in La Paz Bay (BCS, Mexico) and a preliminary investigation on microplastic concentration and polymer composition was also carried out in seawater samples from the same area. The average abundance pattern for the target contaminants was PCBs>DDTs>PBDEs>HCB. Mean concentration values of 8.42ng/g w.w. were found for PCBs, 1.31ng/g w.w. for DDTs, 0.29ng/g w.w. for PBDEs and 0.19ng/g w.w. for HCB. CYP1A-like protein was detected, for the first time, in whale shark skin samples. First data on the average density of microplastics in the superficial zooplankton/microplastic samples showed values ranging from 0.00items/m 3 to 0.14items/m 3 . A focused PCA analysis was performed to evaluate a possible correlation among the size of the whale sharks, contaminants and CYP1A reponses. Further ecotoxicological investigation on whale shark skin biopsies will be carried out for a worldwide ecotoxicological risk assessment of this endangerd species. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. The Geology of Mexico: A Quantitative Evaluation of a Course Designed to Increase the Number of Hispanic Students Participating in the Geosciences at California State University, Sacramento

    Science.gov (United States)

    Hammersley, Lisa C.; Levine, R.; Cornwell, K.; Kusnick, J. E.; Hausback, B. P.

    2012-01-01

    We present a quantitative evaluation of the effectiveness of a newly developed introductory course, Geology of Mexico, in attracting Hispanic students, encouraging them to take more geology courses, and recruiting them to the major. The student population in the Geology of Mexico course was 93% Hispanic compared with 18.5% in Physical Geology. We…

  4. Negligencia en la Educacion de Estudiantes Mexico-Americanos en el Distrito Escolar Unificado Lucia Mar, Pismo Beach, California. (Educational Neglect of Mexican-American Students in Lucia Mar Unified School District, Pismo Beach, California.)

    Science.gov (United States)

    California State Advisory Committee to the United States Commission on Civil Rights.

    California State Advisory Committee (SAC) of the U.S. Commission on Civil Rights held hearings in Santa Maria, California (May 20, 1972) to collect information on civil rights problems of Mexican American students in the Lucia Mar School District. Major issues were community complaints about the arrest of 26 Mexican American students and some…

  5. CTD, salinity, temperature, oxygen, and depth data for Cruise DP01 from the R/V Point Sur in the Viosca Knoll, Gulf of Mexico, 2015-05-01 to 2015-05-08 (NCEI Accession 0142203)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deep water sampling of in situ seawater and associated fauna (cruise DP01, May 1-8, 2015) aboard the R/V Point Sur for an area encompassing roughly 28°N to 29°N...

  6. <書評> Cockcroft, Eva Sperling and Holly Barnet-Sanchez eds., Signs from the Heart : California Chicano Murals., Social and Public Art Resource Center and University of New Mexico Press. 1990, (サインズ・フロム・ザ・ハート:カリフォルニアのチカーノ壁画)

    OpenAIRE

    熊谷, 高秋

    2006-01-01

    Cockcroft, Eva Sperling and Holly Barnet-Sanchez eds., Signs from the Heart : California Chicano Murals., Social and Public Art Resource Center and University of New Mexico Press. 1990, (サインズ・フロム・ザ・ハート:カリフォルニアのチカーノ壁画)

  7. Climatology of landfalling hurricanes and tropical storms in Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Jauregui, E. [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico (UNAM), Mexico, D.F. (Mexico)

    2003-10-01

    The potential for damage from hurricanes landfalling in Mexico is assessed. During the 1951-2000 period, Pacific hurricane hits were more frequent on coastal areas of the northwest of country (e.g., Sinaloa and the southern half of Baja California Peninsula) as well as in southern Mexico (Michoacan). On the Atlantic side, the Yucatan Peninsula and the northern state of Tamaulipas were most exposed to these storms. The hurricane season reaches maximum activity in September for both the Atlantic and Pacific coasts of the country. During the 50 year period, five intense hurricanes (category 5) made landfall on the Gulf/Caribbean coasts, while only one such intense hurricane made a land hit on the Pacific side. While hurricanes affecting Pacific coasts show a marked increase during the last decade, those of the Atlantic side exhibit a marked decrease since the 1970s. However, when considering the frequency of landfalling tropical storms and hurricanes impacting on both littorals of the country, their numbers have considerably increased during the 1990s. [Spanish] Se determino el potencial de dano de los huracanes que entran a tierra en Mexico. Durante el periodo 1951-2000 los impactos de los huracanes del Pacifico fueron mas frecuentes en las areas costeras del noroeste del pais, como Sinaloa y la mitad sur de la peninsula de Baja California, asi como en el sur de Mexico (Michoacan). En el lado del Atlantico la peninsula de Yucatan y el estado norteno de Tamaulipas fueron los mas expuestos a estas tormentas. Para las dos costas del pais, del Pacifico y del Atlantico, la temporada de huracanes alcanza su maxima actividad en septiembre. Durante los 50 anos del periodo de estudio cinco huracanes intensos (categoria 5) tocaron tierra en el lado del Atlantico y uno en el Pacifico. Mientras que los huracanes que afectan las costas del Pacifico muestran un incremento en numero durante la ultima decada, los del Atlantico exhiben una disminucion notable desde la decada de los

  8. Nuevos registros del parásito Probopyrus pacificensis (Isopoda: Bopyridae en el sur de Nayarit y norte de Jalisco, México New records of the parasite Probopyrus pacificensis (Isopoda: Bopyridae in southern Nayarit and northern Jalisco, Mexico

    Directory of Open Access Journals (Sweden)

    Alberto Ocaña-Luna

    2009-04-01

    Full Text Available Se presentan nuevos registros de Probopyrus pacificensis en el arroyo San Francisco, sur de Nayarit y en el arroyo Palo María, norte de Jalisco en el Pacífico mexicano, parasitando a camarones de agua dulce de la especie Macrobrachium tenellum.New observations of Probopyrus pacificensis were recorded in Arroyo San Francisco, southern Nayarit, and Arroyo Palo María, northern Jalisco, in the Mexican Pacific, infesting the freshwater shrimp Macrobrachium tenellum.

  9. [Mortality trends and years of potential life lost from prostate cancer in the 32 states and 7 sociecononomic regions of Mexico, 2000-2010].

    Science.gov (United States)

    Sánchez-Barriga, Juan Jesús

    2013-01-01

    To determine trends of mortality from prostate cancer (PC) and years of potential life lost (YPLL) by federative entity and by socioeconomic region in the period 2000-2010. Records of mortality associated with PC 2000-2010 were obtained from the National Information System of the Secretariat of Health. This information is generated by the National Institute of Statistics and Geography through death certificates issued throughout the country. International Classification of Diseases, 10th revision, codes corresponding to the basic cause of death from PC were identified. Rates of mortality nationwide, by state, and by socioeconomic region were calculated. Rates of YPLL were calculated by federative entity and by socioeconomic region. The seven socioeconomic regions were elaborated by the National Institute of Statistics and Geography and include the 31 states and Mexico City according to indicators that are related to well-being such as education, occupation, health, housing, and employment. Raw mortality rates per 100,000 inhabitants who died from PC increased from 7.8 to 9.8 between 2000-2010. The states and socioeconomic regions with the higher rates of mortality from PC were Sinaloa, Sonora, Baja California Sur, Nayarit, Colima and regions 6 and 3. The state and socioeconomic regions with higher rate of APVP from PC were Aguascalientes, Nuevo León, Campeche, Baja California Sur, Durango and regions 6, 5, 3, 1 and 2. Raw mortality rates per 100,000 inhabitants who died from PC increased from 7.8 to 9.8 between 2000-2010. The states and socioeconomic region with the higher mortality rates were Sinaloa, Sonora, Baja California Sur, Nayarit, Colima and regions 6 and 3. Mexico.

  10. Humboldt's works on Mexico

    Directory of Open Access Journals (Sweden)

    Ulrike Leitner

    2000-10-01

    Full Text Available Article in English, Abstracts in Spanish and English. Humboldt wrote about Mexico from the perspective of a scientific explorer and naturalist. His works include his diaries, the Essai politique sur le royaume de la Nouvelle-Espagne, the Tablas géograficas, the Vues des Cordillères and a geographic atlas. Concerning the scientific aspect, the lack of a section on Mexico in the Relation historique is not a real deficit, since this can be found in the Essai. But only the diaries and letters from the journey, both published by the Alexander-von-Humboldt Research Centre, Berlin, can be considered an adequate substitute.The following will show the origin of Humboldt's writings on Mexico, offer historical and bibliographical facts and present the publications "Beiträge zur Alexander von Humboldt-Forschung", as well as Humboldt’s handwritten estate as far as they are available to us.

  11. First report of myxomatosis in Mexico.

    Science.gov (United States)

    Licón Luna, R M

    2000-07-01

    An outbreak of myxomatosis occurred between September and October 1993 on a rabbit farm in Punta Colnett (Ensenada, Baja California in northwestern Mexico, Transpeninsular Highway, km 128) and was confirmed by the Mexico-USA Commission for Prevention of Foreign Diseases of Animals (CPA). This represents the first officially confirmed case of the disease in Mexico. Like the cases in California (USA), the brush rabbit (Sylvilagus bachmani) seems to be the carrier of the virus, since serum samples from wild rabbits from different areas of the peninsula of Baja California were found to contain antibodies against the myxoma virus.

  12. March 2007 Scripps Institute of Oceanography (SIO) Lidar of the Southern California Coastline: Long Beach to the US/Mexico Border

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This lidar point data set was collected during low tide conditions along an approximately 500-700 meter wide strip of the Southern California coastline within an...

  13. Eolic central Guerrero Negro, BCS, Mexico, performance first year operation; Central eolica Guerrero Negro, BCS, Mexico, resultados del primer ano de operacion

    Energy Technology Data Exchange (ETDEWEB)

    Cadenas Tovar, Roberto; Sanchez Cornejo, Carlos; Lopez Rios, Serafin [Comision Federal de Electricidad, Morelia, Michoacan (Mexico); Ley Romero, Jose R [Comision Federal de Electricidad, Guerrero Negro, Baja California Sur (Mexico)

    2000-07-01

    Comision Federal de Electricidad installed a 600 kW wind turbine in the Guerrero Negro isolated electrical grid to evaluate, under actual operation conditions, the contribution of wind energy in the generation of electricity. This paper describes the performance of the wind turbine in terms of its availability, power curve and electricity produced. The results have been satisfactory, electricity was supplied with a lesser fuel consumption than before. [Spanish] La Comision Federal de Electricidad instalo en Guerrero Negro, Baja California Sur, Mexico un aerogenerador de 600 kW para evaluar en condiciones reales de operacion la integracion de la energia del viento a sistemas electricos aislados basados en diesel. En este trabajo se describen los resultados del primer ano de operacion del aerogenerador en terminos de su disponibilidad, curva de potencia y generacion obtenida. Los resultados han sido satisfactorios, registrandose una reduccion en el consumo de combustible fosil en el sistema.

  14. Economic, environmental and social impacts of geothermal development, and energy savings and efficient use of power in Baja California, Mexico; Impactos economicos, ambientales y sociales del desarrollo geotermico y del ahorro y uso eficiente de la electricidad en Baja California, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Campbell R, Hector E.; Montero A, Gisela [Universidad Autonoma de Baja California, Instituto de Ingenieria, Mexicali, Baja California (Mexico)]. E-mail: hecr@iing.mxl.uabc.mx; Lambert A., Alejandro A. [Universidad Autonoma de Baja California, Facultad de Ingenieria, Mexicali, Baja California (Mexico)

    2011-01-15

    This essay of electrical planning for Baja California, Mexico, includes diagnosis of power production and consumption from 1994-2005, prospective to 2025 if historical trends are maintained, discussion of a systemic plan and its impact on the prospective through energy savings and energy efficient use, combined with an increase of the geothermal energy share. Diagnosis indicates that geothermal capacity in 1998 accounted for 57% of total electric capacity in Baja California, and by 2004 73% of this total electric capacity was based on natural gas, increasing energy dependence on fossil fuels. During this period, electric generation changed from a ratio of 2 to 1 (geothermal steam to fuel oil) to 1 to 1 (geothermal steam to natural gas). The unit cost of natural gas energy with an efficiency of 50% is 24 times the cost of the same unit of geothermal steam with 16% efficiency. Power generation, with fuel oil or simple cycle turbines firing natural gas, costs twice that of combined cycle turbines, while the costs are three times less with geothermal steam. In 2005, as a consequence of a minor contribution of geothermal energy to the power-generation total, production costs increased, reaching $122.80 USD/MWh. The replacement of fuel oil, as power fuel, decreased the SO{sub x} emissions from 4.16 kg/MWh to 0.19 kg/MWh. The combined-cycle fired by natural gas diminished the relative emissions of NO{sub x} and CO{sub 2} by 30%, but the 2.6 million tons of CO{sub x} given off each year did no vary significantly. Using geothermal energy avoids burning 20 million barrels of oil equivalent annually. The Prospective 2005-2025 indicates Baja California requires the installation of an additional 4500 MW to reach 7200 MW. The energy portfolio will become more dependent on natural gas increasing its share from 60% to 86%. Geothermal energy will decrease its share in installed capacity to 10%, eliminating the damping effect on the cost of production. SO{sub x} emissions will

  15. Operations in California during the Mexican American War

    Science.gov (United States)

    2016-05-26

    expansion established a sustained Spanish claim to Alta California. Rugged terrain and long sea routes limited more extensive colonization of California...88 Appendix A: Spanish Exploration and Rule ...................................................................................91...Mexico From the Spanish Conquest to the Present Time, 1530-1890 (New York, NY: New Mexico Historical Publishing Company, 1891), 173. The independent

  16. Constraints on the rheology of the lower crust in a strike-slip plate boundary: evidence from the San Quintín xenoliths, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    T. van der Werf

    2017-12-01

    Full Text Available The rheology of lower crust and its transient behavior in active strike-slip plate boundaries remain poorly understood. To address this issue, we analyzed a suite of granulite and lherzolite xenoliths from the upper Pleistocene–Holocene San Quintín volcanic field of northern Baja California, Mexico. The San Quintín volcanic field is located 20 km east of the Baja California shear zone, which accommodates the relative movement between the Pacific plate and Baja California microplate. The development of a strong foliation in both the mafic granulites and lherzolites, suggests that a lithospheric-scale shear zone exists beneath the San Quintín volcanic field. Combining microstructural observations, geothermometry, and phase equilibria modeling, we estimated that crystal-plastic deformation took place at temperatures of 750–890 °C and pressures of 400–560 MPa, corresponding to 15–22 km depth. A hot crustal geotherm of 40 ° C km−1 is required to explain the estimated deformation conditions. Infrared spectroscopy shows that plagioclase in the mafic granulites is relatively dry. Microstructures are interpreted to show that deformation in both the uppermost lower crust and upper mantle was accommodated by a combination of dislocation creep and grain-size-sensitive creep. Recrystallized grain size paleopiezometry yields low differential stresses of 12–33 and 17 MPa for plagioclase and olivine, respectively. The lower range of stresses (12–17 MPa in the mafic granulite and lherzolite xenoliths is interpreted to be associated with transient deformation under decreasing stress conditions, following an event of stress increase. Using flow laws for dry plagioclase, we estimated a low viscosity of 1.1–1.3×1020 Pa ⋅ s for the high temperature conditions (890 °C in the lower crust. Significantly lower viscosities in the range of 1016–1019 Pa ⋅ s, were estimated using flow laws for wet plagioclase. The

  17. Reconstruction of long-term winter streamflow in the Gulf of California continental watershed

    Science.gov (United States)

    Brito-Castillo, L.; Díaz-Castro, S.; Salinas-Zavala, C. A.; Douglas, A. V.

    2003-07-01

    Applying multiple regression techniques to tree-ring series from Sierra de la Laguna in Baja California Sur, Mexico and Sierra Madre Occidental in Durango, and Tlaxcala, Mexico (A.D. 1384-1997), reconstruction of winter streamflow was performed for data from the central and southern regions of the Gulf of California continental watershed. Each region was defined after applying Varimax Rotated Empirical Orthogonal Function analysis. Streamflow reconstruction was possible from 1840 to 1992 for the central region and from 1712 to 1993 for the southern region. The power spectrums of the reconstructed streamflow series and the Index of the Pacific Decadal Oscillation series (IPDO) show evidence of low frequency (decadal-scale) variations around 40 and 80 years. Tendencies in reconstructed streamflow series and in the IPDO are analyzed and discussed. We conclude that streamflow reconstruction was attainable on a decadal temporal scale. In this sense, the IPDO may be considered a good indicator of future tendencies (in decades) in winter streamflow in the study zone.

  18. Mexico and Central America.

    Science.gov (United States)

    Bronfman, M

    1998-01-01

    This article reviews the literature on migration and HIV/AIDS in Mexico and Central America, including Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, and Panama. Most migrants travel to the US through Mexico. US-Mexico trade agreements created opportunities for increased risk of HIV transmission. The research literature focuses on Mexico. Most countries, with the exception of Belize and Costa Rica, are sending countries. Human rights of migrants are violated in transit and at destination. Migration policies determine migration processes. The Mexican-born population in the US is about 3% of US population and 8% of Mexico's population. About 22% arrived during 1992-97, and about 500,000 are naturalized US citizens. An additional 11 million have a Mexican ethnic background. Mexican migrants are usually economically active men who had jobs before leaving and were urban people who settled in California, Texas, Illinois, and Arizona. Most Mexican migrants enter illegally. Many return to Mexico. The main paths of HIV transmission are homosexual, heterosexual, and IV-drug-injecting persons. Latino migrants frequently use prostitutes, adopt new sexual practices including anal penetration among men, greater diversity of sexual partners, and use of injectable drugs.

  19. Apprentissage en ligne et sur le tas au Mexique | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Laura Dávila est de retour sur les bancs de l'école. Installée à son bureau dans la classe virtuelle @Campus Mexico, cette fonctionnaire mexicaine se renseigne sur son propre gouvernement — ses ministères et son cadre juridique, les lois qui encadrent l'accès à l'information et la responsabilité de la fonction publique, ...

  20. Technological innovations in the horticultural sector in northwestern Mexico: adoption speed and diffusion networks analysis

    Directory of Open Access Journals (Sweden)

    Belem Dolores Avendaño-Ruiz

    2017-09-01

    Full Text Available The article focuses on the identification of innovation adoption and diffusion processes in the export horticultural sector in northwestern Mexico, and the differences identified taking into account the type of producer depending on the production size. The results of the adoption speed index suggests that large producers are distinguished as being early adopters and leaders in innovation adoption in this activity; but as long as there is a technological gap between small and large producers, that is increased even more by economical limita-tions, these will be identified as late adopters for this activity, supported by public programs for its adoption. The study was conducted in four entities of northwestern Mexico, Baja California, Baja California Sur, Sonora and Sinaloa, that in average contribute with 17 % of the national horticultural production. The international market is a strong promotor in innovation adoption, particularly in those related to food safety standards that are adopted by 84 % of the producers. The network analysis highlights the role of union organizations as technological innovation diffusors, e.g. the Confederation of Agricultural Associations of the Sinaloa State, and the Local Agricultural Association of horticulture, Fruits and Legumes of Hermosillo in Sonora.

  1. Reproductive parameters of the southern stingray Dasyatis americana in southern gulf of Mexico Parámetros reproductivos de la raya látigo americana Dasyatis americana en el sur del golfo de México

    OpenAIRE

    Edith Ramírez-Mosqueda; Juan Carlos Pérez-Jiménez; Manuel Mendoza-Carranza

    2012-01-01

    The southern stingray Dasyatis americana (Hildebrand & Schroeder, 1928) is the most landed elasmobranch by small-scale fleets in southern gulf of Mexico. However, little is known of its life history parameters in this region. In this study, a total of 900 specimens were collected from February 2006 to December 2008 to determine the reproductive parameters needed for population assessments by means of ecological risk assessments or demographic analysis. Results suggested that females of D. ame...

  2. A Study on the Attitudes and Opinions of Engineering Students from the University of Baja California, Mexico, on Science, Technology, and Society

    Science.gov (United States)

    Oliveros Ruiz, Maria Amparo; Sevilla Garcia, Juan Jose; Schorr, Michael

    2010-01-01

    A proposal is presented for the incorporation of the concepts of STS into the teaching of science and technology at the Faculty of Engineering, Mexicali Campus, of the University of Baja California. The method outlined for the development of research and the application of the "Opinions Questionnaire on Science, Technology and Society"…

  3. Mexico : tous les projets | Page 2 | CRDI - Centre de recherches ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Sujet: EDUCATION, TELECOMMUNICATIONS. Région: Colombia, Mexico, Peru, Uruguay. Programme: ... Projet. En Amérique latine, les maladies non transmissibles (MNT) sont responsables de trois décès sur quatre. Sujet: NUTRITION. Région: Chile, Mexico. Programme: Food, Environment, and Health. Financement ...

  4. New records of non-resident pinnipeds from the Gulf of California, Mexico Registros nuevos de pinnípedos no-residentes en el golfo de California, México

    Directory of Open Access Journals (Sweden)

    Juan Pablo Gallo-Reynoso

    2010-04-01

    Full Text Available Although the California sea lion (Zalophus californianus is the only pinniped resident in the Gulf of California, there are occasional records of 3 additional species; here we report 4 recent records of the Guadalupe fur seal (Artocephalus townsendi, 6 of the northern elephant seal (Mirounga angustirostris and 2 of the harbor seal (Phoca vitulina. Harbor seals have been observed mostly during the winter-spring months of El Niño years, before water temperature warms in the summer. It is possible that juveniles and subadult and adult males of A. townsendi and M. angustirostris are using the Gulf as an alternative feeding area during the season of intensive feeding as individuals disperse more and more widely as their populations grow.Aunque en el golfo de California, el único pinnípedo residente es el lobo marino de California (Zalophus californianus, existen registros ocasionales de otras 3 especies; en la presente nota se proporcionan 4 registros recientes de lobo fino de Guadalupe (Arctocephalus townsendi, 6 de elefante marino del norte (Mirounga angustirostris y 2 de foca común (Phoca vitulina. La foca común se ha observado principalmente durante los meses de invierno-primavera en años de El Niño, antes del calentamiento anual del agua en verano. Es posible que los juveniles y los machos sub-adultos y adultos tanto de A. townsendi como de M. angustirostris hagan uso del golfo como un sitio alternativo durante la temporada de alimentación intensiva como de su expansión geográfica debido a su incremento poblacional.

  5. Patrones de uso de sitios naturales y artificiales por Branta bernicla nigricans (Anseriformes: Anatidae en Guerrero Negro, Baja California Sur, México Habitat use patterns of the Black Brant Branta bernicla nigricans (Anseriformes: Anatidae in natural and artificial areas of Guerrero Negro, Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Israel Martínez Cedillo

    2013-06-01

    Full Text Available En el complejo lagunar Guerrero Negro-Ojo de Liebre-Exportadora de Sal inverna el 31% de la población de Ganso de collar (Branta bernicla nigricans que utiliza México (31 000 aves en promedio. Nosotros realizamos censos de punto mensuales (noviembre 2006 a abril 2007 en tres sitios para determinar: (1 los efectos de la época del año y del sitio en la estructura poblacional (grupos de edad y (2 la relación del nivel de marea con la abundan- cia y la proporción de aves alimentándose. La proporción general de adultos fue de 0.68. Esta proporción fue mayor en invierno que en primavera. Por sitio en LGN y ESSA disminuyó y en LOL se mantuvo constante. El incremento de aves inmaduras entre el invierno y la primavera se relaciona con su partida primaveral tardía. La alimentación del Ganso de collar en LOL (el sitio de mayor abundancia fue independiente del nivel de marea, lo que se puede relacionar con dos conductas: (1 que las aves se muevan a lo largo de la laguna, para aprovechar el desfase, de hasta cuatro horas en el nivel de marea o (2 que modifiquen sus estrategias de alimentación, para consumir el pasto flotante.The Black Brant is a common inhabitant of the Western Artic American tundra, which migrates to Southern Pacific coasts during the winter season. Approximately, 31 000 birds (31% constitute the Mexican population of Brants at Guerrero Negro, Ojo de Liebre, and Exportadora de Sal lagoon complex; nevertheless, there is little information about the distribution patterns and zone usage. At Guerrero Negro Lagoon (GNL, Ojo de Liebre Lagoon (OLL, both natural sites, and at Exportadora de Sal (ESSA, artificial site we determined by monthly censuses (from November 2006 to April 2007, 08:00-16:00h and observed: (1 season and site effects on population structure (age groups, and (2 the tide level relationship with the abundance and proportion of feeding birds. Within a total of 150 observation hours and 98 birds, our results showed a general 0.68 proportion of adults, that was higher in winter than in spring. The statistics analysis showed no effects by site on the proportion of feeding birds, but we observed a temporal decrease at ESSA and at GNL. In contrast the proportion of feeding birds at OLL was constant. We observed an increase in the juveniles between winter and spring. This increase is related with the differential migration, which mentions that the juveniles are the last to leave the wintering area. In winter the relations of the tide level with the abundance of Brant were: direct at ESSA, inverse at OLL and no relation found at GNL. In spring, no relation was observed in the sites. The proportion of Brants feeding at OLL (the site with the higher abundance was independent of the tide level. This is related with two possible behaviors of the geese: (1 they can move through the lagoon and take advantage of the tidal lag, which is up to four hours; and (2 they can modify their feeding strategies, more on floating eelgrass (Zostera marina.

  6. California Bioregions

    Data.gov (United States)

    California Department of Resources — California regions developed by the Inter-agency Natural Areas Coordinating Committee (INACC) were digitized from a 1:1,200,000 California Department of Fish and...

  7. Overfishing Drivers and Opportunities for Recovery in Small-Scale Fisheries of the Midriff Islands Region, Gulf of California, Mexico: the Roles of Land and Sea Institutions in Fisheries Sustainability

    Directory of Open Access Journals (Sweden)

    Ana Cinti

    2014-03-01

    Full Text Available Institutions play an important role in shaping individual incentives in complex social-ecological systems, by encouraging or discouraging resource overuse. In the Gulf of California, Mexico, there is widespread evidence of declines in small-scale fishery stocks, largely attributed to policy failures. We investigated formal and informal rules-in-use regulating access and resource use by small-scale fishers in the two most important fishing communities of the Midriff Islands region in the Gulf of California, which share several target species and fishing grounds. The Midriff Islands region is a highly productive area where sustainable use of fisheries resources has been elusive. Our study aimed to inform policy by providing information on how management and conservation policies perform in this unique environment. In addition, we contrast attributes of the enabling conditions for sustainability on the commons in an effort to better understand why these communities, albeit showing several contrasting attributes of the above conditions, have not developed sustainable fishing practices. We take a novel, comprehensive institutional approach that includes formal and informal institutions, incorporating links between land (i.e., communal land rights and sea institutions (i.e., fisheries and conservation policies and their effects on stewardship of fishery resources, a theme that is practically unaddressed in the literature. Insufficient government support in provision of secure rights, enforcement and sanctioning, and recognition and incorporation of local arrangements and capacities for management arose as important needs to address in both cases. We highlight the critical role of higher levels of governance, that when disconnected from local practices, realities, and needs, can be a major impediment to achieving sustainability in small-scale fisheries, even in cases where several facilitating conditions are met.

  8. Louse flies on birds of Baja California

    OpenAIRE

    Tella, José Luis; Rodríguez-Estrella, Ricardo; Blanco, Guillermo

    2000-01-01

    Louse flies were collected from 401 birds of 32 species captured in autumn of 1996 in Baja California Sur (México). Only one louse fly species (Microlynchia pusilla) was found. It occurred in four of the 164 common ground doves (Columbina passerina) collected. This is a new a host species for this louse fly.

  9. Diving behavior of sperm whales in relation to behavior of a major prey species, the jumbo squid, in the Gulf of California, Mexico

    OpenAIRE

    Gilly, W.; Bazzino, G.; Markaida, U.; Gendron, Diane; Jaquet, N; Davis, R.W.

    2007-01-01

    Sperm whales occur worldwide and feed largely on meso- and bathypelagic squid, but little is known about the behavioral ecology of this predator and its prey. In the Gulf of California, sperm whales are thought to feed on the abundant jumbo (Humboldt) squid, an ecologically and commercially important species. In this study, we attached satellite-linked dive recorders to 5 sperm whales and pop-up archival transmitting tags to 3 jumbo squid in the same area and time period in order to record th...

  10. The herpetofauna of Sonora, Mexico, with comparisons to adjoining states

    Directory of Open Access Journals (Sweden)

    Enderson, E. F.

    2009-01-01

    Full Text Available Situated in the topographically complex transition between the Neotropics and the temperate biomes of North America,the state of Sonora, Mexico, has an extraordinarily diverse herpetofauna. Surprisingly little research has been conductedon the state’s amphibians and reptiles and many systematic and biogeographic questions remain unanswered. Tofacilitate future research, we provide a checklist of Sonora’s herpetofauna, documenting species presence based onmuseum specimens, our fieldwork, and published research. Sonora’s herpetofauna is placed in a regional biogeographicperspective via a checklist for the six adjoining states together with faunal analyses. A total of 402 species ofamphibians and reptiles are recorded from these seven states. Sonora has the greatest species richness (187 species,followed by Chihuahua (169 species, and Sinaloa (146 species. Sonora's herpetofauna is most similar to that ofChihuahua, with which it shares a long border. Eleven biogeographic affinity-based faunal groups are recognized. Ofthese, three are dominant in Sonora: a core group classified as "Sonoran" demonstrates strong affinity to SonoranDesertscrub and Sinaloan Thornscrub communities; a Tropical group - with many species reaching their northerndistributional limits in the state; and a Madrean group consisting largely of montane species. Our state-level faunalanalysis provides some evidence of peninsular depauperization of the herpetofauna on the Baja California peninsula duein part to the small number of Neotropical species present in Baja California Sur. Our faunal analysis points towarddistinctive mainland and peninsular Sonoran Desert herpetofaunas centered on Sonora and the Baja CaliforniaPeninsula, respectively, each with about 50 non-insular species, and each with species-level endemism nearing 50%.

  11. Assessment of Blue Carbon Storage by Baja California (Mexico) Tidal Wetlands and Evidence for Wetland Stability in the Face of Anthropogenic and Climatic Impacts.

    Science.gov (United States)

    Watson, Elizabeth Burke; Hinojosa Corona, Alejandro

    2017-12-24

    Although saline tidal wetlands cover less than a fraction of one percent of the earth's surface (~0.01%), they efficiently sequester organic carbon due to high rates of primary production coupled with surfaces that aggrade in response to sea level rise. Here, we report on multi-decadal changes (1972-2008) in the extent of tidal marshes and mangroves, and characterize soil carbon density and source, for five regions of tidal wetlands located on Baja California's Pacific coast. Land-cover change analysis indicates the stability of tidal wetlands relative to anthropogenic and climate change impacts over the past four decades, with most changes resulting from natural coastal processes that are unique to arid environments. The disturbance of wetland soils in this region (to a depth of 50 cm) would liberate 2.55 Tg of organic carbon (C) or 9.36 Tg CO₂eq. Based on stoichiometry and carbon stable isotope ratios, the source of organic carbon in these wetland sediments is derived from a combination of wetland macrophyte, algal, and phytoplankton sources. The reconstruction of natural wetland dynamics in Baja California provides a counterpoint to the history of wetland destruction elsewhere in North America, and measurements provide new insights on the control of carbon sequestration in arid wetlands.

  12. Identificación de sitios de encuentro de parejas sexuales en dos ciudades de la frontera sur de México, mediante el método PLACE Identification of meeting sites of new sexual partners in two Southern border cities in Mexico using the PLACE method

    Directory of Open Access Journals (Sweden)

    Mirka Negroni-Belén

    2003-01-01

    Full Text Available OBJETIVO: Identificar sitios de encuentro de nuevas parejas sexuales en dos ciudades de la frontera sur de México. MATERIAL Y MÉTODOS: En un estudio epidemiológico descriptivo se encuestó, en mayo de 2001, a informantes clave de la comunidad en dos ciudades fronterizas del sur de México para identificar sitios de encuentro de nuevas parejas. Se visitó cada sitio reportado y se encuestó a una persona del lugar. De una submuestra de sitios, se encuestó a personas que socializaban en los mismos. RESULTADOS: Los informantes clave de la comunidad reportaron 134 sitios en Chetumal y 111 en Ciudad Hidalgo. Se obtuvo información de las características de 89 sitios en Chetumal y 42 en Ciudad Hidalgo, ambos con escasas actividades preventivas del VIH/SIDA. Cerca de 21% de usuarios encuestados reportaron haber conocido una nueva pareja en los sitios en las últimas cuatro semanas. CONCLUSIONES: Son necesarias acciones de prevención en los sitios de encuentro de nuevas parejas sexuales. Este método puede proveer información para planificar futuras intervenciones.OBJECTIVE: To identify the meeting sites of new sexual partners in two Southern border cities in Mexico. MATERIAL AND METHODS: A descriptive epidemiologic study was carried out in May 2001, by surveying key informants in two border cities. Each reported site was visited to interview a resident subject. Subjects socializing in a subsample of sites were also interviewed. RESULTS: The key informants of the community reported 134 meeting sites in Chetumal and 111 in Ciudad Hidalgo. Both sites had scarce HIV/AIDS prevention activities. Characteristics were obtained for 89 sites in Chetumal and 42 in Ciudad Hidalgo. Almost 21% of interviewees reportedly met a new sexual partner in these sites in the past four weeks. CONCLUSIONS: Preventive actions are needed in meeting sites of new sexual partners. This method may provide information to plan for future interventions.

  13. Les jeunes sur Internet

    OpenAIRE

    Gallez, Sarah; Lobet-Maris, Claire

    2013-01-01

    Basée sur une approche ethnographique, cet article présente une typologie originale de profils types de jeunes (12-18 ans) concernant leurs pratiques sociales d’Internet. Cette typologie a été construite au terme d‘un suivi de près d'une année d’un panel de jeunes comprenant des observations participantes, des entretiens en face à face et en ligne et des journaux de bord. Cette typologie, recouvrant divers régimes de signification que revêt Internet pour les jeunes, tend à démontrer que la to...

  14. Isolation, characterization, and antibiotic resistance of Vibrio spp. in sea turtles from Northwestern Mexico

    Science.gov (United States)

    Zavala-Norzagaray, Alan A.; Aguirre, A. Alonso; Velazquez-Roman, Jorge; Flores-Villaseñor, Héctor; León-Sicairos, Nidia; Ley-Quiñonez, C. P.; Hernández-Díaz, Lucio De Jesús; Canizalez-Roman, Adrian

    2015-01-01

    The aerobic oral and cloacal bacterial microbiota and their antimicrobial resistance were characterized for 64 apparently healthy sea turtles captured at their foraging grounds in Ojo de Liebre Lagoon (OLL), Baja California Sur (BCS), Mexico (Pacific Ocean) and the lagoon system of Navachiste (LSN) and Marine Area of Influence (MAI), Guasave, Sinaloa (Gulf of California). A total of 34 black turtles (Chelonia mydas agassizii) were sampled in OLL and eight black turtles and 22 olive ridley turtles (Lepidochelys olivacea) were sampled in LSN and MAI, respectively from January to December 2012. We isolated 13 different species of Gram-negative bacteria. The most frequently isolated bacteria were Vibrio alginolyticus in 39/64 (60%), V. parahaemolyticus in 17/64 (26%), and V. cholerae in 6/64 (9%). However, V. cholerae was isolated only from turtles captured from the Gulf of California (MAI). Among V. parahaemolyticus strains, six O serogroups and eight serovars were identified from which 5/17 (29.4%) belonged to the pathogenic strains (tdh+ gene) and 2/17 (11.7%) had the pandemic clone (tdh+ and toxRS/new+). Among V. cholerae strains, all were identified as non-O1/non-O139, and in 4/6 (66%) the accessory cholera enterotoxin gene (ace) was identified but without virulence gene zot, ctxA, and ctxB. Of the isolated V. parahaemolyticus, V. cholerae, and V. alginolyticus strains, 94.1, 33.4, and 100% demonstrated resistance to at least one commonly prescribed antibiotic (primarily to ampicillin), respectively. In conclusion, the presence of several potential (toxigenic) human pathogens in sea turtles may represent transmission of environmental microbes and a high-risk of food-borne disease. Therefore, based on the fact that it is illegal and unhealthy, we discourage the consumption of sea turtle meat or eggs in northwestern Mexico. PMID:26161078

  15. Isolation, characterization, and antibiotic resistance of Vibrio spp. in sea turtles from Northwestern Mexico.

    Science.gov (United States)

    Zavala-Norzagaray, Alan A; Aguirre, A Alonso; Velazquez-Roman, Jorge; Flores-Villaseñor, Héctor; León-Sicairos, Nidia; Ley-Quiñonez, C P; Hernández-Díaz, Lucio De Jesús; Canizalez-Roman, Adrian

    2015-01-01

    The aerobic oral and cloacal bacterial microbiota and their antimicrobial resistance were characterized for 64 apparently healthy sea turtles captured at their foraging grounds in Ojo de Liebre Lagoon (OLL), Baja California Sur (BCS), Mexico (Pacific Ocean) and the lagoon system of Navachiste (LSN) and Marine Area of Influence (MAI), Guasave, Sinaloa (Gulf of California). A total of 34 black turtles (Chelonia mydas agassizii) were sampled in OLL and eight black turtles and 22 olive ridley turtles (Lepidochelys olivacea) were sampled in LSN and MAI, respectively from January to December 2012. We isolated 13 different species of Gram-negative bacteria. The most frequently isolated bacteria were Vibrio alginolyticus in 39/64 (60%), V. parahaemolyticus in 17/64 (26%), and V. cholerae in 6/64 (9%). However, V. cholerae was isolated only from turtles captured from the Gulf of California (MAI). Among V. parahaemolyticus strains, six O serogroups and eight serovars were identified from which 5/17 (29.4%) belonged to the pathogenic strains (tdh (+) gene) and 2/17 (11.7%) had the pandemic clone (tdh (+) and toxRS/new (+)). Among V. cholerae strains, all were identified as non-O1/non-O139, and in 4/6 (66%) the accessory cholera enterotoxin gene (ace) was identified but without virulence gene zot, ctxA, and ctxB. Of the isolated V. parahaemolyticus, V. cholerae, and V. alginolyticus strains, 94.1, 33.4, and 100% demonstrated resistance to at least one commonly prescribed antibiotic (primarily to ampicillin), respectively. In conclusion, the presence of several potential (toxigenic) human pathogens in sea turtles may represent transmission of environmental microbes and a high-risk of food-borne disease. Therefore, based on the fact that it is illegal and unhealthy, we discourage the consumption of sea turtle meat or eggs in northwestern Mexico.

  16. Isolation, Characterization, and Antibiotic Resistance of Vibrio spp. in Sea Turtles from Northwestern Mexico

    Directory of Open Access Journals (Sweden)

    Alan A. eZavala-Norzagaray

    2015-06-01

    Full Text Available The aerobic oral and cloacal bacterial microbiota and their antimicrobial resistance were characterized for 64 apparently healthy sea turtles captured at their foraging grounds in Ojo de Liebre Lagoon (OLL, Baja California Sur, Mexico (Pacific Ocean and the lagoon system of Navachiste (LSN and Marine Area of Influence (MAI, Guasave, Sinaloa (Gulf of California. A total of 34 black turtles (Chelonia mydas agassizii were sampled in OLL and eight black turtles and 22 olive ridley turtles (Lepidochelys olivacea were sampled in LSN and MAI, respectively from January to December 2012. We isolated 13 different species of Gram-negative bacteria. The most frequently isolated bacteria were Vibrio alginolyticus in 39/64 (60%, V. parahaemolyticus in 17/64 (26% and V. cholerae in 6/64 (9%,. However, V. cholerae was isolated only from turtles captured from the Gulf of California (MAI. Among V. parahaemolyticus strains, six O serogroups and eight serovars were identified from which 5/17 (29.4% belonged to the pathogenic strains (tdh+ gene and 2/17 (11.7% had the pandemic clone (tdh+ and toxRS/new+. Among V. cholerae strains, all were identified as non-O1/non-O139, and in 4/6 (66% the accessory cholera enterotoxin gene (ace was identified but without virulence gene zot, ctxA and ctxB. Of the isolated V. parahaemolyticus, V. cholerae and V. alginolyticus strains, 94.1%, 33.4% and 100% demonstrated resistance to at least one commonly prescribed antibiotic (primarily to ampicillin, respectively. In conclusion, the presence of several potential (toxigenic human pathogens in sea turtles may represent transmission of environmental microbes and a high-risk of food-borne disease. Therefore, based on the fact that it is illegal and unhealthy, we discourage the consumption of sea turtle meat or eggs in northwestern Mexico.

  17. Structural inheritance versus magmatic weakening: What controls the style of deformation at rift segment boundaries in the Gulf of California, Mexico?

    Science.gov (United States)

    Seiler, Christian; Gleadow, Andrew; Kohn, Barry

    2013-04-01

    Rifts are commonly segmented into several hundred kilometre long zones of opposing upper-plate transport direction with boundaries defined by accommodation and transfer zones. A number of such rift segments have been recognized in the Gulf of California, a youthful oceanic basin that is currently undergoing the rift-drift transition. However, detailed field studies have so far failed to identify suitable structures that could accommodate the obvious deformation gradients between different rift segments, and the nature of strain transfer at segment boundaries remains enigmatic. The Bocana transfer zone (BTZ) in central Baja California is a linear, WNW striking structural discontinuity separating two rift segments with different magnitudes and styles of extensional deformation. North of the BTZ, the Libertad fault is part of the Main Gulf Escarpment, which represents the breakaway fault that separates the Gulf of California rift to the east from the relatively stable western portion of the Baja peninsula. The N-striking Libertad escarpment developed during the Late Miocene (~10-8Ma) and exhibits a topographic relief of ca. 1,000m along a strike-length of ca. 50km. Finite displacement decreases from ~1000m in the central fault segment to ~500m further south, where the fault bends SE and merges with the BTZ. In the hanging wall of the Libertad fault, a series of W-tilted horsts are bound along their eastern margins by two moderate-displacement E-dipping normal faults. South of the BTZ, extension was much less than further north, which explains the comparatively subdued relief and generally shallower tilt of pre-rift strata in this area. The BTZ itself is characterized by two en echelon WNW-ESE striking dextral-oblique transfer faults with a significant down-to-the-NNE extensional component. Strain is transferred from the Libertad breakaway fault onto the transfer faults over a distance of >20km through a network of interacting normal, oblique and strike-slip faults

  18. Structural and Tectonic Map Along the Pacific-North America Plate Boundary in Northern Gulf of California, Sonora Desert and Valle de Mexicali, Mexico, from Seismic Reflection Evidence

    Science.gov (United States)

    Gonzalez-Escobar, M.; Suarez-Vidal, F.; Mendoza-Borunda, R.; Martin Barajas, A.; Pacheco-Romero, M.; Arregui-Estrada, S.; Gallardo-Mata, C.; Sanchez-Garcia, C.; Chanes-Martinez, J.

    2012-12-01

    Between 1978 and 1983, Petróleos Mexicanos (PEMEX) carried on an intense exploration program in the northern Gulf of California, the Sonora Desert and the southern part of the Mexicali Valley. This program was supported by a seismic reflection field operation. The collected seismic data was 2D, with travel time of 6 s recording, in 48 channels, and the source energy was: dynamite, vibroseis and air guns. Since 2007 to present time, the existing seismic data has been re-processing and ire-interpreting as part of a collaboration project between the PEMEX's Subdirección de Exploración (PEMEX) and CICESE. The study area is located along a large portion of the Pacific-North America plate boundary in the northern Gulf of California and the Southern part of the Salton Trough tectonic province (Mexicali Valley). We present the result of the processes reflection seismic lines. Many of the previous reported known faults were identify along with the first time described located within the study region. We identified regions with different degree of tectonic activity. In structural map it can see the location of many of these known active faults and their associated seismic activity, as well as other structures with no associated seismicity. Where some faults are mist placed they were deleted or relocated based on new information. We included historical seismicity for the region. We present six reflection lines that cross the aftershocks zone of the El Mayor-Cucapah earthquake of April 4, 2010 (Mw7.2). The epicenter of this earthquake and most of the aftershocks are located in a region where pervious to this earthquake no major earthquakes are been reported. A major result of this study is to demonstrate that there are many buried faults that increase the seismic hazard.

  19. Composición taxonómica y aspectos zoogeográficos de peces de profundidad (90-540m del Golfo de California, México Taxonomic composition and zoogeographical aspects of deep sea fishes (90-540m from the Gulf of California, Mexico

    Directory of Open Access Journals (Sweden)

    Juana López-Martínez

    2012-03-01

    ía son fundamentales para desarrollar cualquier tema de biodiversidad y manejo pesqueroTaxonomic composition and zoogeographical aspects of deep sea fishes (90-540m from the Gulf of California, Mexico. The Gulf of California has a high variety of ecosystems that allow different services and the fishery resources play a prominent role in its ecology, evolution and economics. Fish coastal species have been previously reported for most coastal areas, especially those species that are subject to fishing, however, little is known on the species from deep sea zones, due to sampling cifficulties. We studied the deep sea fishes collected with trawl nets during three research surveys in the Gulf of California, Mexico in 2004-2005. We provide a systematic checklist and some notes on biogeographical aspects. For this, 74 fishing hauls were done, and a total of 9 898 fishes were captured, belonging to two classes, 15 orders, 35 families, 53 genera and 70 species. The best represented families in number of species were: Paralichthyidae (eight, Serranidae (six, and Scorpaenidae and Triglidae with five species each one. The typical families from deep waters were: Ophidiidae, Moridae, Lophiidae, Scorpaenidae, Triglidae, Paralichthydae, Pleuronectidae and Cynoglossidae. Size range varied from 13cm for the Splinose searobin (Bellator xenisma to 234cm in the Pacific Cutlassfish (Trichiurus nitens. The biogeographical affinity showed that species with affinity to the East Tropical Pacific (ETP dominated, followed by species from San Diego-Panamic, San Diego-Panamic-Peruvian-Chilean and Oregonian-Cortes provinces, respectively. A biogeographic overlap was found in the fauna, which reflects the Gulf of California’s geographical position, with distribution limits of species from temperate, tropical and warm-temperature transition affinities, divisions that characterize the Gulf of California. Taxonomic status of fish with a focus on composition, location, characterization and zoogeography

  20. Effects of Pleistocene environmental changes on the distribution and community structure of the mammalian fauna of Mexico

    Science.gov (United States)

    Ceballos, Gerardo; Arroyo-Cabrales, Joaquín; Ponce, Eduardo

    2010-05-01

    Biological communities in Mexico experienced profound changes in species composition and structure as a consequence of the environmental fluctuations during the Pleistocene. Based on the recent and fossil Mexican mammal checklists, we determine the distribution, composition, diversity, and community structure of late Pleistocene mammalian faunas, and analyze extinction patterns and response of individual species to environmental changes. We conclude that (1) differential extinctions occurred at family, genus, and species level, with a major impact on species heavier than 100 kg, including the extinction all proboscideans and several ruminants; (2) Pleistocene mammal communities in Mexico were more diverse than recent ones; and (3) the current assemblages of species are relatively young. Furthermore, Pleistocene relicts support the presence of biogeographic corridors; important refugia existed as well as centers of speciation in isolated regions. We identified seven corridors: eastern USA-Sierra Madre Oriental corridor, Rocky Mountains-Sierra Madre Occidental corridor, Central United States-Northern Mexico corridor, Transvolcanic Belt-Sierra Madre del Sur corridor, western USA-Baja California corridor, Tamaulipas-Central America gulf lowlands corridor, and Sonora-Central America Pacific lowlands corridor. Our study suggests that present mammalian assemblages are very different than the ones in the late Pleistocene.

  1. Nonessential metals in striped marlin and Indo-Pacific sailfish in the southeast Gulf of California, Mexico: concentration and assessment of human health risk.

    Science.gov (United States)

    Soto-Jiménez, M F; Amezcua, F; González-Ledesma, R

    2010-04-01

    Seventeen sailfish (Istiophorus platypterus; 166-246 cm long) and 13 striped marlin (Tetrapturus audax; 159-254 cm long) specimens from the southern Gulf of California were analyzed for As, Cd, Hg, and Pb concentrations. More than 20% of the As and Cd levels exceeded the guideline levels of the World Health Organization (WHO), the U.S. Food and Drug Administration, and the European Union. About 65-90% of the specimens exceeded the limit value for Hg. Pb levels in billfish were significantly lower than guideline values. The intakes of As and Cd through billfish consumption by the population represented 20-40% of the provisional tolerable weekly intake (PTWI) values as recommended by the WHO. Levels of Hg exceeded the PTWI value. Pb intake represented 1 indicate risk for As and Hg; the risk from As was estimated assuming that 20% of the total As was inorganic. These metals can affect the nervous system and intellectual and physical development of unborn children and infants. A national moratorium on billfish consumption in México is recommended for children (0-6 years old), pregnant women, and women planning pregnancy.

  2. Heavy metals in the clam Megapitaria squalida collected from wild and phosphorite mine-impacted sites in Baja California, Mexico: considerations for human health effects.

    Science.gov (United States)

    Méndez, Lia; Palacios, Elena; Acosta, Baudilio; Monsalvo-Spencer, Pablo; Alvarez-Castañeda, Ticul

    2006-06-01

    The "chocolate clam" Megapitaria squalida, is widely consumed by the population of several localities along the Pacific coast. Clams collected from seven stations in Bahía de la Paz, a bay within the Gulf of California, before and after the summer rainy season were analyzed for Pb, Ni, Cd, Mn, Zn, Cu, and Fe. The location of the sampling sites significantly affected the concentration of metals in clam tissues, but not in relation to the proximity to alleged contaminated sites. Clams from a site close to a phosphate mine had the highest levels of Pb, but only in April, and the highest concentrations of Cd were recorded in clams collected in areas with no anthropogenic activities. Clams from sites considered clean had higher levels of Cd, Fe, Zn, and Mn. The mean concentrations (microg/g dry weight) ranged from 0.1 to 7.8 for Pb, from 1.9 to 8.8 for Ni, from 1.5 to 11.1 for Cd, from 2.5 to 14.1 for Mn, from 47.2 to 64.6 for Zn, from 5.4 to 18.7 for Cu, and from 154 to 558 for Fe. Collecting clams in sites apparently pristine is no guarantee that metals will be in low concentrations.

  3. Assessment of Blue Carbon Storage by Baja California (Mexico Tidal Wetlands and Evidence for Wetland Stability in the Face of Anthropogenic and Climatic Impacts

    Directory of Open Access Journals (Sweden)

    Elizabeth Burke Watson

    2017-12-01

    Full Text Available Although saline tidal wetlands cover less than a fraction of one percent of the earth’s surface (~0.01%, they efficiently sequester organic carbon due to high rates of primary production coupled with surfaces that aggrade in response to sea level rise. Here, we report on multi-decadal changes (1972–2008 in the extent of tidal marshes and mangroves, and characterize soil carbon density and source, for five regions of tidal wetlands located on Baja California’s Pacific coast. Land-cover change analysis indicates the stability of tidal wetlands relative to anthropogenic and climate change impacts over the past four decades, with most changes resulting from natural coastal processes that are unique to arid environments. The disturbance of wetland soils in this region (to a depth of 50 cm would liberate 2.55 Tg of organic carbon (C or 9.36 Tg CO2eq. Based on stoichiometry and carbon stable isotope ratios, the source of organic carbon in these wetland sediments is derived from a combination of wetland macrophyte, algal, and phytoplankton sources. The reconstruction of natural wetland dynamics in Baja California provides a counterpoint to the history of wetland destruction elsewhere in North America, and measurements provide new insights on the control of carbon sequestration in arid wetlands.

  4. Distribution of Cd, Cu, Fe, Mn, Pb and Zn in selected tissues of juvenile whales stranded in the SE Gulf of California (Mexico).

    Science.gov (United States)

    Ruelas-Inzunza, J; Páez-Osuna, F

    2002-09-01

    With the aim of knowing the concentration and distribution of essential and nonessential metals in selected tissues of whales, analysis of Cd, Cu, Fe, Mn, Pb and Zn were carried out in kidney, liver and muscle of the gray whale Eschrichtius robustus and the sperm whale Physeter catodon. Whales were found stranded in the southeast Gulf of California. Individuals were in a juvenile stage; mean length of whales was 9.3 m for E. robustus and 7 m for P. catodon. Sequence of metal concentrations was Fe>Zn>Cu>Mn>Cd>Pb in E. robustus, and Fe>Zn>Cu>Cd>Mn>Pb in P. catodon. In E. robustus, highest concentrations of Cu, Mn, Pb and Zn (17.2, 19.6, 0.9 and 388 microg g(-1), respectively) were measured in liver, Cd (5.7 microg g(-1)) in kidney and Fe (1009 microg g(-1)) in muscle. In P. catodon, the highest levels of Cu, Fe and Pb (48.6, 5200 and 4.2 microg g(-1), respectively) were found in liver, Cd and Zn (94 and 183 microg g(-1)) in kidney and Mn (8 microg g(-1)) in muscle. Metal concentrations reported here were not considered to contribute to the stranding of specimens.

  5. Perceptions of fishers to sea turtle bycatch, illegal capture and consumption in the San Ignacio-Navachiste-Macapule lagoon complex, Gulf of California, Mexico.

    Science.gov (United States)

    Aguilar-González, Myrna E; Luna-González, Antonio; Aguirre, Alonso; Zavala-Norzagaray, Alan A; Mundo-Ocampo, Manuel; González-Ocampo, Héctor A

    2014-01-01

    In this study, 10% of all registered fishermen in the coastal towns of Navachiste in Sinaloa, in northwestern Mexico, answered a survey designed to collect data on their perceptions of the following topics: the impact of turtle meat consumption; human health; bycatch; illegal turtle fishing; the illegal sea turtle market; the local economy; pollution; environmental education; the success of protective legislation; and sea turtle-based ecotourism. Perceptions were analyzed using the fuzzy logic method through classification into 5 fuzzy membership sets: VL, very low; L, low; M, moderate; H, high; VH, very high. The 9 topics generated decision areas upon applying fuzzy inference that revealed the membership level of the answers in each fuzzy set. The economic potential of sea turtle-based ecotourism and the economic profitability of the illegal turtle meat market were perceived as VL. Conservation legislation was perceived as H, although inefficiently applied due to corruption. Ecotourism and impacts on sea turtles were perceived as VL, because they were deemed unprofitable activities at the individual and community levels. Environmental education was perceived as L, because it centers on nesting, hatching and releasing turtles and is directed at elementary and middle-school students. While fishers perceive a serious negative impact of fishing activities on sea turtles in the San Ignacio-Navachiste-Macapule area, they do not see themselves individually as part of the problem. Achieving sea turtle conservation in this region requires: suitable ecotourism infrastructure, government investments in promotion, and studies to estimate the minimum number of tourists needed to assure profitability. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

  6. The Carotenogenesis Pathway via the Isoprenoid-β-carotene Interference Approach in a New Strain of Dunaliella salina Isolated from Baja California Mexico

    Directory of Open Access Journals (Sweden)

    Luis Enrique Gutierrez-Millan

    2009-02-01

    Full Text Available D. salina is one of the recognized natural sources to produce β-carotene, and an useful model for studying the role of inhibitors and enhancers of carotenogenesis. However there is little information in D. salina regarding whether the isoprenoid substrate can be influenced by stress factors (carotenogenic or selective inhibitors which in turn may further contribute to elucidate the early steps of carotenogenesis and biosynthesis of β-carotene. In this study,Dunaliella salina (BC02 isolated from La Salina BC Mexico, was subjected to the method of isoprenoids-β-carotene interference in order to promote the interruption or accumulation of the programmed biosynthesis of carotenoids. When Carotenogenic and non-carotenogenic cells of D. salina BC02 were grown under photoautotrophicgrowth conditions in the presence of 200 µM fosmidomycin, carotenogenesis and the synthesis of β-carotene were interrupted after two days in cultured D. salina cells. This result is an indirect consequence of the inhibition of the synthesis of isoprenoids and activity of the recombinant DXR enzyme thereby preventing the conversionof 1-deoxy-D-xylulose 5-phosphate (DXP to 2-C-methyl-D-erythritol (MEP and consequently interrupts the early steps of carotenogenesis in D. salina. The effect at the level of proteins and RNA was not evident. Mevinolin treated D. salina cells exhibited carotenogenesis and β-carotene levels very similar to those of control cell cultures indicating that mevinolin not pursued any indirect action in the biosynthesis of isoprenoids and had no effect at the level of the HMG-CoA reductase, the key enzyme of the Ac/MVA pathway.

  7. Knowledge and beliefs about malaria transmission and practices for vector control in Southern Mexico Conocimientos y creencias acerca del paludismo y prácticas para el control de vectores en el sur de México

    Directory of Open Access Journals (Sweden)

    Américo David Rodríguez

    2003-04-01

    Full Text Available OBJECTIVE: To investigate the knowledge and beliefs about malaria transmission and practices for vector control in eight villages on the coastal plain of Chiapas, Mexico. MATERIAL AND METHODS: A cross-sectional survey was conducted during May and June 1995 in Chiapas, Mexico. A questionnaire to investigate family structure, knowledge on malaria transmission, preventive measures and attitudes towards seeking treatment was applied to both family heads of a sample of households. Associations were analyzed by estimating odds ratios with confidence intervals and p values, using bivariate and multivariate logistic regression methods. RESULTS: Malaria knowledge was poor and only 48% associated malaria with mosquito bites. The perceived benefit of indoor residual spraying was associated to a reduction of mosquitoes, a reduction in the numbers of cockroaches and rats, but only 3% associated it directly with the prevention of malaria transmission. Most villagers (97.6% agreed with the indoor residual spraying of insecticides. Ninety nine percent of villagers had mosquito bednets, 75.7% used them all year round. Other measures used by villagers to prevent mosquito bites were smoke and mosquito coils. Above 40% of villagers self-medicated when any member of the family had a fever episode, but 51% attended proper health services (community dispensary, private physician, health worker. About 61% used pesticides for agricultural or livestock purposes and 55% applied them themselves. Women had a greater participation as family health promoters, with 70% of the housewives being in charge of the application of self-protection preventive measures. CONCLUSIONS: Educational programs aimed at increasing awareness on the participation of mosquitoes on malaria transmission could promote community participation in malaria control in the region.OBJETIVO: Investigar el conocimiento, las creencias sobre paludismo y las prácticas para el control de vectores en ocho

  8. Foire aux questions sur la bourse Regard canadien sur le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC CRDI

    Pour ce qui est de la bourse Regard canadien sur le développement international, il y a deux catégories. La première catégorie est destinée à des étudiants du niveau du doctorat intéressés à exécuter des recherches sur les liens existant entre les politiques du Canada en matière d'aide internationale, de commerce ...

  9. Estimation of Seismic and Aseismic Deformation in Mexicali Valley, Baja California, Mexico, in the 2006-2009 Period, Using Precise Leveling, DInSAR, Geotechnical Instruments Data, and Modeling

    Science.gov (United States)

    Sarychikhina, Olga; Glowacka, Ewa; Robles, Braulio; Nava, F. Alejandro; Guzmán, Miguel

    2015-11-01

    Ground deformation and seismicity in Mexicali Valley, Baja California, Mexico, the southern part of the Mexicali-Imperial valley, are influenced by active tectonics and human activity. In this study, data from two successive leveling surveys in 2006 and 2009/2010 are used to estimate the total deformation occurred in Mexicali Valley during 2006-2009. The leveling data span more than 3.5 years and include deformation from several natural and anthropogenic sources that acted at different temporal and spatial scales during the analyzed period. Because of its large magnitude, the aseismic anthropogenic deformation caused by fluid extraction in the Cerro Prieto geothermal field obscures the deformation caused by other mechanisms and sources. The method of differential interferograms stacking was used to estimate the aseismic (interseismic tectonic and anthropogenic) components of the observed displacement, using SAR images, taken in 2007 during a period when no significant seismicity occurred in the study area. After removing the estimated aseismic signal from the leveling data, residual vertical displacement remained, and to identify possible sources and mechanisms of this displacement, a detailed analysis of records from tiltmeters and creepmeters was performed. The results of this analysis suggest that the residual displacement is mainly caused by moderate-sized seismicity in the area of study. Modeling of the vertical ground deformation caused by the coseismic slip on source fault (primary mechanism) of the two most important earthquakes, May 24, 2006 (Mw = 5.4) and December 30, 2009 (Mw = 5.8), was performed. The modeling results, together with the analysis of geotechnical instruments data, suggests that this moderate-sized seismicity influences the deformation in the study area by coseismic slip on the source fault, triggered slip on secondary faults, and soft sediments deformation.

  10. The color of urban dust as an indicator of contamination by potentially toxic elements: the case of Ensenada, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    José L. Cortés

    2015-01-01

    Full Text Available La contaminación por elementos potencialmente tóxicos (EPT no se evalúa periódicamente, ya que los análisis químicos son de costo elevado. Las cenizas y humos de combustión otorgan color obscuro al suelo y afectan la salud de la población. El color podría funcionar como indicador proxy. En este trabajo se diseñó una metodología para probar el uso del color del polvo urbano como indicador de contaminación por EPT y se identificó el color más contaminado. Se analizaron 86 muestras de polvo de Ensenada, Baja California. El color de las muestras se midió y los índices de color (IC se calcularon con el sistema RGB. El Níquel (Ni, Cobre (Cu, Zinc (Zn, Plomo (Pb, Rubidio (Rb, Vanadio (V, Estroncio (Sr e Itrio (Y se analizaron por fluorescencia de rayos X. Las muestras se agruparon por color con las tablas Munsell; los agrupamientos se validaron con un análisis discriminante utilizando los IC. Las regresiones múltiples indicaron que existe relación entre los IC y los EPT. Las medianas de los elementos analizados en las muestras agrupadas por color fueron diferentes (Kruskal-Wallis, P < 0.05. El polvo gris contiene mayores concentraciones de Pb, Cu, Zn y Ni. Los índices de color del polvo urbano pueden considerarse una metodología proxy debido al bajo costo, rapidez y confiabilidad.

  11. Interdisciplinary approach on evaluation and sustainable usage of the water resources in the semi-arid Northwest Mexico to counter the imbalance of water: Case study Valle de Guadalupe, Baja California

    Science.gov (United States)

    Kretzschmar, T.; Hernandez, R.; Valenzuela, C.; Cabello, A.

    2012-12-01

    In the Baja California peninsula are several watersheds present, of which the hydrogeological conditions are of great importance to communities in the area. The Valle de Guadalupe watershed, for instance has a wine industry of national importance. Irrigation of crops is carried out exclusively with water from the aquifer, which consists of Quaternary sediments filling this depression of Post-Miocene age. Apart from the use of the aquifer by the wine industry, the water utility of Ensenada operates 10 drinking water wells with a total capacity of 320 L/s or 42% of supply in the valley. In the arid northern Mexico mountain front recharge is an important recharge source to the aquifers. Other important recharge sources are related to direct infiltration of the precipitation, recharge from runoff into streams (mountain block recharge) and the provision by active faults. The knowledge of the aquifer is crucial to maintain sustainable management of water resources in the Valle de Guadalupe. This intense use of water resources is reflected in a degradation of the aquifer water quality and reduced water table. The integrated approach for a sustainable evaluation and usage of the aquifer includes besides the hydrogeological evaluation, the determination of the water stress on the vineyards as well as the usage of treated waste water as alternative resource as well the evaluation of the effects of climatic variations and measurement and modeling of the vegetation, the main interface between atmosphere and soil, affecting the hydrology in the process of interception, infiltration, runoff and evapotranspiration. With these detailed ongoing studies we expect to identify and counter imbalance of water in the study area. This requires 1) modeling and hydrogeological studies for the determination of the present and future imbalance 2) estimation of the impacts of industrial activities on water resources 3) characterization of alternative water sources, 4) optimization of the water

  12. Mexico Geoid Heights (MEXICO97)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This 2' geoid height grid for Mexico, and North-Central America, is the MEXICO97 geoid model. The computation used about one million terrestrial and marine gravity...

  13. Oribatid mites and springtails from a coffee plantation in Sierra Sur, Oaxaca, Mexico Ácaros oribatídeos e colêmbolos de uma plantação de café em Sierra Sur, Oaxaca, México

    Directory of Open Access Journals (Sweden)

    Aldo Bernal Rojas

    2009-08-01

    Full Text Available The objective of this work was to compare the oribatid mite and springtail communities in three plots with different soil use - Coffee (CP, secondary vegetation or fallow fields (acahual, A and a cloud mountain forest (CMF - within a coffee plantation located in Santa Maria Huatulco, Oaxaca State, Mexico. In each plot 20 samples (10 of soil, 10 of litter were taken and processed in Berlese funnels. The extracted fauna was preserved in 70% ethanol. A total of 3,031 oribatid mites belonging to 33 species, and 1,177 specimens of springtails belonging to 43 species, were collected. The number of species recorded was: 27 at CP (14 oribatids; 13 springtails, 44 at A (19 oribatids; 25 springtails and 62 at CMF (32 for each group. A total of 26 oribatid and 27 springtail species was found in the soil, and 25 oribatid and 32 springtail species were found in the litter. The most abundant species were the oribatids Rostroztes foveolatus (Haplozetidae, Tectocepheus sp. (Tecocepheidae, Karenella sp. (Oppidae, Atropacarus (Hoplophorella cf. fonseciai (Phthiracaridae, Epilohmannia pallida americana (Epilohmannidae, and the springtails Ceratophysella cf. gibbosa (Hypogastruridae, Mesaphorura sp. (Tullbergidae and Proisotoma cf. minuta (Isotomidae. Fourteen families and 18 species of Oribatida species and 5 families and 34 species of Collembola were recorded for the first time for the State.O objetivo deste trabalho foi comparar as comunidades de ácaros oribatídeos e de colêmbolos em três parcelas com uso diferente do solo - plantação de café (CP, a vegetação secundária ou pousio (acahual, A e a floresta nublada de montanha (CMF - em uma plantação de café situada na municipalidade de Santa María Huatulco, estado de Oaxaca, México. Vinte amostras foram tomadas em cada lote (dez do solo, dez de serapilheira e processadas em funis de Berlese. A fauna extraída foi preservada em álcool 70%. Um total de 3.031 ácaros oribatídeos pertencentes a 33 esp

  14. Baja California: literatura y frontera

    Directory of Open Access Journals (Sweden)

    Gabriel Trujillo Muñoz

    2014-06-01

    Baja California is a region that not only has migration problems and criminal violence because of the war of drugs or is a space of border conflicts in close neighborhood with the United States of America. Baja California is too a geographic space of culture and art, of creative writing and struggle to narrate the things and persons that here live, a plain sight, like their house, like their home, like a center of creation. This text give a cultural context of the border literature in the north of Mexico like a phenomenon in notice because his own merits, books and writers.

  15. Socioeconomic Incentives for Migration from Mexico to the United States: Magnitude, Recent Changes, and Policy Implications.

    Science.gov (United States)

    1980-07-01

    35 10. Interregionally Comparable Monthly Real Wage Gradient for Low-Skilled Laborers, 1969, 1974 and 1978 Mexico City- Ciudad ...51 15. Socioeconomic Opportunity Gradient, 1970 Mexico City - Ciudad Juarez - Albuquerque ............ 52 16. Socioeconomic Opportunity...Nogales 35. San Luis Potosi Norte 65. Puebla Sier!:a 6. Chihuahua Cd. Juarez 36. San Luis Potosi Sur 66. Puebla Area Metro. 7. Chihuahua Sierra 37

  16. of the U. S.-Mexico Border

    Directory of Open Access Journals (Sweden)

    Sophie Meritet

    2006-01-01

    Full Text Available This paper studies the possible impacts of liquefied natural gas (LNG projects on natural gas prices on both sides of the U. S.-Mexico border in California. In that state gas prices are high and demand is expected to grow. Several projects for LNG facilities have been proposed and have to cope with public opinions against them. In Baja California, four LNG projects are under development given the rising demand forecasted for the next years. After a detailed study of the opportunity for LNG projects, we conclude with an analysis of the fundamentals of the current and future price formation in both sides of the U. S.- Mexico border.

  17. A new Bomolochus (Copepoda parasitica) from the California Grunion

    NARCIS (Netherlands)

    Stock, J.H.

    1955-01-01

    The grunion, Leuresthes tenuis (AYRES) (family Atherinidae), a fish with a distribution limited to coastal southern California, U.S.A., and Lower California, Mexico, yielded the recently described copepod Caligus olsoni PEARSE, 1953, and still another parasitic copepod which proved to be an

  18. The Bandini-Cota Adobe, Prado Dam, Riverside County, California.

    Science.gov (United States)

    1983-11-01

    Museum Papers 2. Re- printed. Ballena , Ramona, California. Originally pub- lished 1936, San Diego Museum. Rush, Philip S. 1965 Some Old Ranchos and...California. Ballena , Socorro, New Mexico. Whitehead, Richard S. (editor) 1980 An Archeological and Restoration Study of Mission La Pur- isima

  19. An annotated distributional checklist of exotic freshwater fishes from the Baja California Peninsula, Mexico Lista comentada sobre la distribución de peces dulceacuícolas exóticos de la península de Baja California, México

    Directory of Open Access Journals (Sweden)

    Gorgonio Ruiz-Campos

    2012-03-01

    Full Text Available We documented the distributional status of 27 exotic fish species in the inland waters of the Baja California Peninsula, Mexico, based on voucher specimens collected from 122 sites between 1977 and 2010, and on published records. The species reported here are representatives of genera from the Atlantic drainages of North America (Ictalurus, Ameiurus, Pylodictis, Morone, Lepomis, Pomoxis, Dorosoma, Cyprinella, and Micropterus, Middle America (Poecilia, Gambusia, and Xiphophorus, Eurasia (Cyprinus and Carassius, and Africa (Tilapia and Oreochromis. The family containing the highest number of species is Centrarchidae (7 species followed by Ictaluridae and Poeciliidae (6 species each. Four species were determined to be invasive due to their wide distribution and fast dispersal through the Peninsula (Gambusia affinis, Poecilia reticulata, Lepomis cyanellus, and Tilapia sp. cf. zillii. We analyze the impacts of exotic species on the native populations of 3 species with problems of conservation: Cyprinodon macularius (endangered, Fundulus lima (endangered, and Gasterosteus aculeatus (vulnerable. Alien fishes have been introduced for a variety of reasons in Mexico: ornament, sport, aquaculture, biological control, and by accident. In some cases fish introductions were carried out for more than one reason.El estatus de la distribución de peces exóticos es documentado para 27 especies en las aguas continentales de la península de Baja California, México, basado en registros de ejemplares recolectados en 122 localidades durante el período de 1977 a 2010, así como registros referidos en la literatura. Las especies aquí reportadas son representativas de géneros que proceden de la vertiente Atlántica de Norteamérica (Ictalurus, Ameiurus, Pylodictis, Morone, Lepomis, Pomoxis, Dorosoma, Cyprinella y Micropterus, Mesoamérica (Poecilia, Gambusia y Xiphophorus, Eurasia (Cyprinus y Carassius y África (Tilapia y Oreochromis. La familia con mayor n

  20. Mexico-U.S. Migration Patterns: Implications for the Development of Binational Collaboration in Adult Education.

    Science.gov (United States)

    Kissam, Ed

    Recent new patterns in Mexico-United States migration are examined briefly, and the implications of each for planning and implementing adult education programs are discussed. The patterns noted include: (1) migration of greater distances and from new areas in Mexico, both to border areas in Mexico and to locations in California and the West Coast;…

  1. Un regard sur le quotidien

    Directory of Open Access Journals (Sweden)

    Bernard Zuppinger

    2005-10-01

    Full Text Available Sur la base d’une situation particulière tirée d’une expérience de terrain récente, cette contribution cherche à montrer comment l’observation participante peut, dans le quotidien d’une enquête sur les stratégies foncières des habitants d’un quartier périphérique de Ouagadougou, être porteuse d’ambiguïté et de distance en fonction du changement de statut de l’enquêteur. Et comment cette distance implique de considérer une méthodologie basée sur un empirisme «instruit» pour reprendre le terme de O. Schwartz.

  2. California Air Basins

    Data.gov (United States)

    California Department of Resources — Air ResourcesCalifornia Air Resources BoardThe following datasets are from the California Air Resources Board: * arb_california_airbasins - California Air BasinsThe...

  3. Mexico : tous les projets | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Six femmes sur dix de l'Amérique centrale sont victimes de violence sexuelle au cours de leur migration à travers le Mexique, rapporte Amnistie Internationale. Sujet: VIOLENCE, MIGRANTS. Région: Guatemala, Mexico. Programme: Governance and Justice. Financement total : CA$ 397,100.00. Prévention de la violence, ...

  4. Tierra y violencia en la Sierra Sur de Oaxaca, Mexico

    National Research Council Canada - National Science Library

    Villavicencio Rojas, Josue Mario

    2013-01-01

    En los Estados de Oaxaca, Chiapas, Veracruz y Guerrero se presentan en mayor frecuencia comunidades rurales con elevados indicadores de pobreza, analfabetismo, y ausencia de los servicios mas elementales...

  5. Exploring scenarios of light pollution from coastal development reaching sea turtle nesting beaches near Cabo Pulmo, Mexico

    Directory of Open Access Journals (Sweden)

    Gregory M. Verutes

    2014-12-01

    Full Text Available New coastal development may offer economic benefits to resort builders and even local communities, but these projects can also impact local ecosystems, key wildlife, and the draw for tourists. We explore how light from Cabo Cortés, a proposed coastal development in Baja California Sur, Mexico, may alter natural light cues used by sea turtle hatchlings. We adapt a viewshed approach to model exterior light originating from the resort under plausible zoning scenarios. This spatially explicit information allows stakeholders to evaluate the likely impact of alternative development options. Our model suggests that direct light’s ability to reach sea turtle nesting beaches varies greatly by source location and height—with some plausible development scenarios leading to significantly less light pollution than others. Our light pollution maps can enhance decision-making, offering clear guidance on where to avoid elevated lamps or when to recommend lighting restrictions. Communities can use this information to participate in development planning to mitigate ecological, aesthetic and economic impacts from artificial lighting. Though tested in Mexico, our approach and free, open-source software can be applied in other places around the world to better understand and manage the threats of light pollution to sea turtles.

  6. [Mercury concentration in breast milk of women from northwest Mexico; possible association with diet, tobacco and other maternal factors].

    Science.gov (United States)

    Gaxiola-Robles, Ramón; Zenteno-Savín, Tania; Labrada-Martagón, Vanessa; Celis de la Rosa, Alfredo de Jesús; Acosta Vargas, Baudillo; Méndez-Rodríguez, Lía Celina

    2013-01-01

    To determine THg levels in milk of women from Northwest Mexico and its potential association with maternal factors such as diet and tobacco smoke. The study was performed in 108 milk samples donated by women in Baja California Sur. Data were stratified into three groups of 36 donors by number of pregnancies. General data, smoking, exposure to environmental tobacco smoke and seafood intake were explored. THg levels were measured using atomic absorption spectrophotometry. The difference between groups was evaluated with non-parametric statistics. To explain the possible association of the different variables with THg concentrations in milk, generalized linear models were performed. THg levels ranged from 1.23 μg/L in single-pregnancy women (GI) to 2.96 μg/L for women with 3 or more pregnancies (GIII) (p = 0.07). In the GI group THg concentration was 175% higher (p = 0.02) in women who do not eat fish, compared to those who eat fish. In the generalized linear model to adjust THg concentrations, the variables were: age, number of pregnancies, breastfeeding duration and exposure to tobacco smoke (p ≤ 0.05). Fish consumption was the factor that better adjusted models, relative to THg levels. The contribution associated to this factor was low; therefore, consumption of fish from the coast of Baja California Sur is safe. Tobacco increased Hg concentrations in breast milk; it is necessary to avoid the smoking habit during pregnancy and breast-feeding. Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.

  7. Gender-related family head schooling and Aedes aegypti larval breeding risk in Southern Mexico Escolaridad con relación al género de los jefes de familia y el riesgo de cría de Aedes aegypti en el sur de México

    Directory of Open Access Journals (Sweden)

    Rogelio Danis-Lozano

    2002-06-01

    Full Text Available Objective. To investigate if family head genre-associated education is related to the risk of domiciliary Aedes aegypti larval breeding in a dengue-endemic village of Southern Mexico. Material and Methods. A family head was considered to have a low education level if he/she had not completed elementary school. To estimate larval breeding risk within each household, a three-category Maya index was constructed using a weighted estimation of controllable and disposable domestic water containers. A socio-economic index was constructed based on household construction characteristics. Results. Low-level education of either family head was associated to higher larval breeding risk. Households with low-educated mothers had more larval breeding containers. These associations persisted after adjusting for household socio-economic level. Conclusions. These results indicate that households with female family heads with low education levels accumulate more containers that favor Ae. aegypti breeding, and that education campaigns for dengue control should be addressed to this part of the population.Objetivo. Investigar si la escolaridad asociada con el género de los jefes de familia de una localidad endémica de dengue en el sur de México estaba relacionada con el riesgo de cría intradomiciliaria de Aedes aegypti. Material y métodos. Se consideró que un jefe de familia tenía baja educación si él/ella no había completado la educación primaria. Para estimar el riesgo de cría larvaria en cada domicilio se construyó un Indice Maya de tres categorías a partir de la estimación ponderada de recipientes controlables y desechables. Se construyó un índice socioeconómico basado en los materiales de construcción de la casa. Resultados. Niveles bajos de educación de los jefes de familia se asociaron con niveles altos de riesgo de cría de larvas de mosquitos. Pero las casas con jefas de familia con baja educación tuvieron más recipientes en riesgo para

  8. The social representation of drug trafficking like laborer optionAt first glance, the State of Baja California (Mexico and the Department of Valle del Cauca (Colombia do not have much in common. They belong to different countries and have significant di

    Directory of Open Access Journals (Sweden)

    Lilian Paola Ovalle

    2010-11-01

    Full Text Available At first glance, the State of Baja California (Mexico and the Department of Valle del Cauca (Colombia do not have much in common. They belong to different countries and have significant differences in their history and their social, cultural, political and economic structures. However these places have a commonality--namely the fact that for more than three decades they have become epicenters of drug trafficking. In both of these territories, trafficking groups and international business networks have appropriated the region in order to frame their illegal project. This paper summarizes the findings of field research conducted during December 2008. Knowing and comparing the social representations of drug trafficking in these two territories, offers significant elements that help understand the integration processes and social penetration of drug trafficking in local contexts—and shed light on processes that have helped consolidate these practices as viable labor options.

  9. LA MUERTE CRISTIANA ENTRE LA PASTORAL EVANGELIZADORA Y LAS PRÁCTICAS INDÍGENAS: UN ACERCAMIENTO COMPARATIVO (MÉXICO CENTRAL Y LOS ANDES DEL CENTRO-SUR, SIGLO XVI - PRINCIPIO DEL XVII) / CHRISTIAN DEATH, AS CONCEPTUALIZED BY MISSIONARIES, AS OPPOSED TO NATIVE PRACTICE: A COMPARATIVE STUDY (CENTRAL MEXICO VERSUS CENTRAL AND SOUTHERN ANDES, XVITH - BEGINNING OF THE XVIITH CENTURY)

    National Research Council Canada - National Science Library

    Pierre Ragon

    2012-01-01

    ... en el México central y lo que pasó en los Andes del Centro-Sur. En Nueva España, durante decenios, los religiosos se descuidaron por completo de tal cosa mientras tanto muy temprano averiguaron y denunciaron numerosas desviaciones en los Andes...

  10. Consumo literario en lenguas indígenas: experiencias de revitalización desde el Sur de México\\Literary consumption in indigenous languages: revitalization experiences from Southern Mexico\\Consumo literário em línguas indígenas: experiências de revitalização desde o Sul do México

    National Research Council Canada - National Science Library

    Lorena Córdova Hernández

    2016-01-01

      This article analyzes, from several ethnographic experiences in Southern Mexico, the way in which agents for language revitalization design the programs or projects of literacy in indigenous languages...

  11. Biomagnification of mercury and selenium in blue shark Prionace glauca from the Pacific Ocean off Mexico.

    Science.gov (United States)

    Escobar-Sánchez, Ofelia; Galván-Magaña, Felipe; Rosíles-Martínez, René

    2011-12-01

    The aim of this study was to determine the biomagnification of mercury through the principal prey of the blue shark, Prionace glauca, off the western coast of Baja California Sur, Mexico, as well as the relationship between mercury and selenium in blue sharks. High levels of mercury were found in shark muscle tissues (1.39 ± 1.58 μg/g wet weight); these values are above the allowed 1.0 μg/g for human consumption. The mercury to selenium molar ratio was 1:0.2. We found a low correlation between mercury bioaccumulation and shark size. Juveniles have lower concentrations of mercury than adults. Regarding the analyzed prey, the main prey of the blue shark, pelagic red crab, Pleuroncodes planipes, bioaccumulated 0.04 ± 0.01 μg/g Hg wet weight, but the prey with higher bioaccumulation was the bullet fish Auxis spp. (0.20 ± 0.02 μg/g wet weight). In terms of volume, the red crab P. planipes can be the prey that provides high levels of mercury to the blue shark.

  12. Expected years of life lost through road traffic injuries in Mexico.

    Science.gov (United States)

    Murillo-Zamora, Efrén; Mendoza-Cano, Oliver; Trujillo-Hernández, Benjamín; Guzmán-Esquivel, José; Medina-González, Alfredo; Huerta, Miguel; Sánchez-Piña, Ramón Alberto; Lugo-Radillo, Agustin

    2017-01-01

    Road traffic injuries (RTIs) are a leading cause of premature mortality, mainly in low- and middle-income countries Objective: To estimate the 2014 burden of RTIs in Mexico calculating years of life lost (YLL) and age-standardized YLL rates (ASYLL), and to evaluate sex, age, and region-related differences in premature mortality. Mortality data were obtained from the National Institute of Statistics and Geography and 14,637 deaths of individuals 15 years of age and older were analyzed. The YLL and ASYLL were computed. The overall burden of RTIs was 332,922 YLL and 82.4% of the deaths occurred in males. Males from 25 to 34 years of age and females from 15 to 24 years of age showed the highest age-adjusted YLL rates (933 and 158 YLL per 100,000 inhabitants, respectively). The national ASYLL rate was 416 per 100,000 inhabitants and the highest state-stratified mortality rates were observed in Tabasco (851), Sinaloa (709), Durango (656), Zacatecas (642), and Baja California Sur (570). RTIs contributed to the premature mortality rate in the study population. Our findings may be useful from a health policy perspective for designing and prioritizing interventions focused on the prevention of premature loss of life.

  13. La piraterie sur le web

    CERN Multimedia

    2002-01-01

    Les échanges de toutes sortes sont facilités à l'extrême par le web: des forums, des vidéoconférences, le commerce à distance, ou tout simplement la célérité des courriers électroniques ou la convivialité des chats, tout cela participe de la société de communication. Une certaine partie du monde découvre le nouvel horizon des échanges quasi instantanés, mais... les transactions sur le web sont-elles vraiment s res?

  14. Ecoregions of California

    Science.gov (United States)

    Griffith, Glenn E.; Omernik, James M.; Smith, David W.; Cook, Terry D.; Tallyn, Ed; Moseley, Kendra; Johnson, Colleen B.

    2016-02-23

    (2000), and Omernik and Griffith (2014).California has great ecological and biological diversity. The State contains offshore islands and coastal lowlands, large alluvial valleys, forested mountain ranges, deserts, and various aquatic habitats. There are 13 level III ecoregions and 177 level IV ecoregions in California and most continue into ecologically similar parts of adjacent States of the United States or Mexico (Bryce and others, 2003; Thorson and others, 2003; Griffith and others, 2014).The California ecoregion map was compiled at a scale of 1:250,000. It revises and subdivides an earlier national ecoregion map that was originally compiled at a smaller scale (Omernik, 1987; U.S. Environmental Protection Agency, 2013). This poster is the result of a collaborative project primarily between U.S. Environmental Protection Agency (USEPA) Region IX, USEPA National Health and Environmental Effects Research Laboratory (Corvallis, Oregon), California Department of Fish and Wildlife (DFW), U.S. Department of Agriculture (USDA)–Natural Resources Conservation Service (NRCS), U.S. Department of the Interior–Geological Survey (USGS), and other State of California agencies and universities.The project is associated with interagency efforts to develop a common framework of ecological regions (McMahon and others, 2001). Reaching that objective requires recognition of the differences in the conceptual approaches and mapping methodologies applied to develop the most common ecoregion-type frameworks, including those developed by the USDA–Forest Service (Bailey and others, 1994; Miles and Goudy, 1997; Cleland and others, 2007), the USEPA (Omernik 1987, 1995), and the NRCS (U.S. Department of Agriculture–Soil Conservation Service, 1981; U.S. Department of Agriculture–Natural Resources Conservation Service, 2006). As each of these frameworks is further refined, their differences are becoming less discernible. Regional collaborative projects such as this one in California

  15. A review on advances in seismology in Mexico after 30 years from the 1985 earthquake

    Science.gov (United States)

    Castro, Raúl R.; Pérez-Campos, Xyoli; Zúñiga, Ramón; Ramírez-Guzmán, Leonardo; Aguirre, Jorge; Husker, Allen; Cuéllar, Armando; Sánchez, Tomás

    2016-10-01

    The 19 September 1985 (Mw8.1) earthquake, located on the Michoacán coast, Mexico, generated great damage in Mexico City, more than 300 km away from the epicentral area. Other important cities near the coast and in central Mexico also suffered severe damage. Thirty years after this important event, the National Autonomous University of Mexico (UNAM), the Centro de Investigación Científica y de Educación Superior de Ensenada, Baja California (CICESE) and other institutions organized a conference to discuss the scientific advances, particularly in seismology, that had taken place in Mexico since then.

  16. Northwestern Mexico as seen from the Gemini 12 spacecraft

    Science.gov (United States)

    1966-01-01

    Area of northwestern Mexico as seen from the Gemini 12 spacecraft during its 16th revolution of the earth. View is looking northwest. Body of water in foreground is Gulf of California. Pacific Ocean is in background. Peninsula in center of picture is Baja California. States of Sonora (upper right) and Sinaloa (lower center) of Mexican mainland is in right foreground. City of Guaymas, Sonora, is near center of picture.

  17. Reconnaissance Report for Navigation Improvements (Reduction of Shoaling) at Santa Cruz Harbor Santa Cruz County, California

    Science.gov (United States)

    1992-05-01

    Central California Coast. Ghost Town Publications, Canmel CA 93921. Rickets , Edward F., Jack Calvin & Joel W. Hedgepeth. 1985. Between Pacific Tides...banning of DDT, birds have begun to return in force. The brown pelican now breeds in waters of southern California and Mexico and migrate into the Santa

  18. California Political Districts

    Data.gov (United States)

    California Department of Resources — This is a series of district layers pertaining to California'spolitical districts, that are derived from the California State Senateand State Assembly information....

  19. IMPACT DE METARHIZIUM ANISOPLIAE VAR ACRIDUM, SUR LES ...

    African Journals Online (AJOL)

    Deux investigations ont porté sur l'impact direct du champignon Metarhizium anisopliae var acridum (IMI-91609 :souche de Zonocerus variegatus) sur la mortalité et sur son impact indirect sur la progéniture de deux hyménoptères : Anagyrus lopezi (De Santis) (Hymenoptera : Encyrtidea) utilisé dans la lutte biologique ...

  20. The combined effects of acidification and hypoxia on pH and aragonite saturation in the coastal waters of the California current ecosystem and the northern Gulf of Mexico

    Science.gov (United States)

    Feely, Richard A.; Okazaki, Remy R.; Cai, Wei-Jun; Bednaršek, Nina; Alin, Simone R.; Byrne, Robert H.; Fassbender, Andrea

    2018-01-01

    Inorganic carbon chemistry data from the surface and subsurface waters of the West Coast of North America have been compared with similar data from the northern Gulf of Mexico to demonstrate how future changes in CO2 emissions will affect chemical changes in coastal waters affected by respiration-induced hypoxia ([O2] ≤ 60 μmol kg-1). In surface waters, the percentage change in the carbon parameters due to increasing CO2 emissions are very similar for both regions even though the absolute decrease in aragonite saturation is much higher in the warmer waters of the Gulf of Mexico. However, in subsurface waters the changes are enhanced due to differences in the initial oxygen concentration and the changes in the buffer capacity (i.e., increasing Revelle Factor) with increasing respiration from the oxidation of organic matter, with the largest impacts on pH and CO2 partial pressure (pCO2) occurring in the colder West Coast waters. As anthropogenic CO2 concentrations begin to build up in subsurface waters, increased atmospheric CO2 will expose organisms to hypercapnic conditions (pCO2 >1000 μatm) within subsurface depths. Since the maintenance of the extracellular pH appears as the first line of defense against external stresses, many biological response studies have been focused on pCO2-induced hypercapnia. The extent of subsurface exposure will occur sooner and be more widespread in colder waters due to their capacity to hold more dissolved oxygen and the accompanying weaker acid-base buffer capacity. Under present conditions, organisms in the West Coast are exposed to hypercapnic conditions when oxygen concentrations are near 100 μmol kg-1 but will experience hypercapnia at oxygen concentrations of 260 μmol kg-1 by year 2100 under the highest elevated-CO2 conditions. Hypercapnia does not occur at present in the Gulf of Mexico but will occur at oxygen concentrations of 170 μmol kg-1 by the end of the century under similar conditions. The aragonite saturation

  1. Seismicity of the Earth 1900-2010 Mexico and vicinity

    Science.gov (United States)

    Rhea, Susan; Dart, Richard L.; Villaseñor, Antonio; Hayes, Gavin P.; Tarr, Arthur C.; Furlong, Kevin P.; Benz, Harley M.

    2011-01-01

    Mexico, located in one of the world's most seismically active regions, lies on three large tectonic plates: the North American plate, Pacific plate, and Cocos plate. The relative motion of these tectonic plates causes frequent earthquakes and active volcanism and mountain building. Mexico's most seismically active region is in southern Mexico where the Cocos plate is subducting northwestward beneath Mexico creating the deep Middle America trench. The Gulf of California, which extends from approximately the northern terminus of the Middle America trench to the U.S.-Mexico border, overlies the plate boundary between the Pacific and North American plates where the Pacific plate is moving northwestward relative to the North American plate. This region of transform faulting is the southern extension of the well-known San Andreas Fault system.

  2. September 1985 Mexico City, Mexico Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The magnitude 8.1 earthquake occurred off the Pacific coast of Mexico. The damage was concentrated in a 25 square km area of Mexico City, 350 km from the epicenter....

  3. EFFET DE LA DENSITE SUR LES PARAMETRES ...

    African Journals Online (AJOL)

    USER

    L'étude vise à déterminer l'effet de l'association légumineuse-cocotier et de la densité des peuplements de Acacia auriculaeformis sur la croissance des arbres et la production de bois. Deux types d'arrangements spatiaux et 3 écartements en plantation ont été étudiés, en zone littorale sur sables quaternaires en Côte.

  4. en Baja California

    Directory of Open Access Journals (Sweden)

    Elmyra Ybañez Zepeda

    2007-01-01

    Full Text Available In the future, the population of 60 years old or older will increase in absolute and relative numbers at a very rapid pace in Mexico. Using data from Censo general de población y vivienda 2000, Encuesta sobre migración en la frontera norte de México and Consejo Nacional de Población (Conapo, the purpose of this article is twofold: first of all, to analyze the aging process in the municipalities of Tijuana and Mexicali, located in the state of Baja California, which has a very low proportion of the eldest; and second of all, to examine the role of migration in this process. Tijuana has a younger population which is aging slowly due to a very intense immigration of young workers and potential parents. Mexicali, on the other hand, has a high percentage of a native population that is aging unrelentingly, and it also has a lower flow of immigrants who are older, and includes a high concentration of persons who had previously resided in the United States.

  5. Lessons from 15 years of monitoring sudden oak death and forest dynamics in California forests

    Science.gov (United States)

    Margaret Metz; J. Morgan Varner; Ross Meentemeyer; Kerri Frangioso; David Rizzo

    2017-01-01

    Monitoring host composition and disease impacts began 15 years ago in what would become a network of permanent forest monitoring plots throughout the known and predicted range of Phytophthora ramorum in California coastal forests. Stretching ~500 miles from Big Sur to the Oregon border, the network captures variation in interactions among...

  6. Un article du Canadian Geographic se penche sur la recherche sur ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    17 mars 2016 ... Manifestants à Kampala marchent vers la cour en 2012 pour livrer plainte sur le retard de la délivrance sur le jugement du cas CEHURD impliquant Sylvia Nalubowa et Jennifer Anguko, deux femmes mortes en accouchant (Photo : CEHURD). Un chercheur subventionné par le CRDI retient l'attention de la ...

  7. Mechanisms of oblique breakup : a tectonic study of the Gulf of California from Neogene to present

    OpenAIRE

    Bot, Anna

    2016-01-01

    The Gulf of California (GOC) is an example of highly-oblique rift. Oceanic accretion started 3.6 Ma ago at its southern end. The earliest continental extension started during the Miocene, in a back-arc setting, in connection with the subduction of the Pacific plate (PAC) beneath North America (NAM). ln this study, I reconstitute the strain evolution along the proximal Baja California margin. For this, I used original tectonic and seismological data which I collected in Baja California Sur (BC...

  8. Mexico; Mexique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-06-01

    This document summarizes the key energy data for Mexico: 1 - energy organizations and policy: Ministry of energy (SENER), Comision Reguladora de Energia (CRE), Ministry of Finances, Ministry of trade and industrial development (SECOFI), national commission for energy savings (CONAE); 2 - companies: federal commission of electricity (CFE), Minera Carbonifera Rio Escondido (MICARE - coal), Pemex (petroleum); 3 - energy production: resources, electric power, petroleum, natural gas; 4 - energy consumption; 5 - stakes and perspectives. Some economic and energy indicators are summarized in a series of tables: general indicators, supply indicators (reserves, refining and electric capacity, energy production, foreign trade), demand indicators (consumption trends, end use, energy independence, energy efficiency, CO{sub 2} emissions), energy status per year and per energy source. (J.S.)

  9. A dendrochronology based fire history of Jeffry pine-mixed conifer forests in the Sierra San Pedro Martir, Mexico

    Science.gov (United States)

    Scott L. Stephens; Carl N. Skinner; Samantha J. Gill

    2003-01-01

    Conifer forests in northwestern Mexico have not experienced systematic fire suppression or logging, making them unique in western North America. Fire regimes of Pinus jeffreyi Grev. & Balf. mixed conifer forests in the Sierra San Pedro Martir, Baja California, Mexico, were determined by identifying 105 fire dates from 1034 fire scars in 105 specimens. Fires were...

  10. Segmentation du muscle pectoral sur une mammographie

    OpenAIRE

    Boucher, Arnaud; Jouve, Pierre; Cloppet, Florence; Vincent, Nicole

    2009-01-01

    National audience; L'objectif de cette étude est la segmentation du muscle pectoral sur une mammographie. Ce travail a pour but de faciliter le recalage géométrique de paires d'images mammographiques par l'extraction fiable de points de repère. La sémantique de l'image est exploitée pour extraire des points de repère basés sur l'anatomie. La technique d'extraction utilisée est basée sur les contours actifs pour lesquels nous proposons de construire différentes énergies.

  11. Adolescent Drug Use in Mexico and among Mexican American Adolescents in the United States: Environmental Influences and Individual Characteristics.

    Science.gov (United States)

    Felix-Ortiz, Maria; Velazuez, Jorge A Villatoro; Medina-Mora, Maria Elena; Newcomb, Michael D.

    2001-01-01

    Compares cigarette, alcohol, and illegal drug use among high school students in Baja California Norte (BCN), Mexico with Mexican American students in Los Angeles (LA), California (N=516). Demographic variables, individual characteristics, and environmental influences were considered. Reports that more BCN students used alcohol and more LA students…

  12. Cartes sur fonds d'images spatiales

    Directory of Open Access Journals (Sweden)

    Fernand VERGER

    1988-06-01

    Full Text Available La qualité géométrique, la vue synoptique sur de grandes étendues, le caractère souvent expressif des images obtenues à partir de l'espace ont provoqué l'utilisation de fonds d'images spatiales avec des surcharges chorogra phiques. On peut proposer une typologie de ces documents sur fonds d'images satellitaires dont un spécimen au 1/25 000 est présenté à partir des données SPOT.

  13. Southwest Regional Climate Hub and California Subsidiary Hub assessment of climate change vulnerability and adaptation and mitigation strategies

    Science.gov (United States)

    Emile Elias; Caiti Steele; Kris Havstad; Kerri Steenwerth; Jeanne Chambers; Helena Deswood; Amber Kerr; Albert Rango; Mark Schwartz; Peter Stine; Rachel Steele

    2015-01-01

    This report is a joint effort of the Southwest Regional Climate Hub and the California Subsidiary Hub (Sub Hub). The Southwest Regional Climate Hub covers Arizona, California, Hawai‘i and the U.S. affiliated Pacific Islands, Nevada, New Mexico, and Utah and contains vast areas of western rangeland, forests, and high-value specialty crops (Figure 1). The California Sub...

  14. New records and description of two new species of carideans shrimps from Bahía Santa María-La Reforma lagoon, Gulf of California, Mexico (Crustacea, Caridea, Alpheidae and Processidae).

    Science.gov (United States)

    Salgado-Barragán, José; Ayón-Parente, Manuel; Zamora-Tavares, Pilar

    2017-01-01

    Two new species of the family Alpheidae: Alpheus margaritaesp. n. and Leptalpheus melendezensissp. n. are described from Santa María-La Reforma, coastal lagoon, SE Gulf of California. Alpheus margaritaesp. n. is closely related to A. antepaenultimus and A. mazatlanicus from the Eastern Pacific and to A. chacei from the Western Atlantic, but can be differentiated from these by a combination of characters, especially the morphology of the scaphocerite and the first pereopods. Leptalpheus melendezensissp. n. resembles L. mexicanus but can be easily differentiated because L. melendezensissp. n. has the anterior margin of the carapace broadly rounded and has only one spine on the mesial margin of ischium in the major cheliped, versus an acute rostrum and an unarmed major cheliped. Additionally, a phylogenetic analysis was used to explore the relationships of these two new taxa. These results show that Alpheus margaritaesp. n. and Leptalpheus melendezensissp. n. are indeed related to the species against which we are comparing them, and demonstrate that they can be considered as different species. Additional specimens of Leptalpheus cf. mexicanus, Ambidexter panamensis and A. swifti are recorded for the first time in the Santa María-La Reforma coastal lagoon.

  15. Subsurface imaging in a sector of Cerro Prieto transform fault near to pull-apart basin, Mexicali Valley, Baja California, Mexico, based on crooked lines 2D seismic reflection.

    Science.gov (United States)

    Mares-Agüero, M. A.; González-Escobar, M.; Arregui, S.

    2016-12-01

    In the transition zone between San Andres continental transformation system and the coupled transform faults system and rifting of Gulf of California is located the Cerro Prieto pull-apart basin delimitated by Imperial fault (northeast) and Cerro Prieto fault (CPF) (southwest), this last, is the limit west of Cerro Prieto geothermic field (CPGF). Crooked lines 2D seismic reflection, covering a portion near the intersection of CPF and CPGF are processed and interpreted. The seismic data were obtained in the early 80's by Petróleos Mexicanos (PEMEX). By decades, technical and investigation works in Cerro Prieto geothermic field and its vicinity had mapped faults at several depths but do not stablish a clear limit where this faults and CPF interact due the complex hydrothermal effects imaging the subsurface. The profiles showing the presence of a zone of uplift effect due to CPF. Considering the proximity of the profiles to CPF, it is surprising almost total absence of faults. A strong reflector around 2 km of depth, it is present in all profiles. This seismic reflector is considered a layer of shale, result of the correlation with a well located in the same region.

  16. Wildfires Rage in Southern California

    Science.gov (United States)

    2003-01-01

    Large plumes of smoke rising from devastating wildfires burning near Los Angeles and San Diego on Sunday, October 26, 2003, are highlighted in this set of images from the Multi-angle Imaging SpectroRadiometer (MISR). These images include a natural color view from MISR's nadir camera (left) and an automated stereo height retrieval (right). The tops of the smoke plumes range in altitude from 500 - 3000 meters, and the stereo retrieval clearly differentiates the smoke from patches of high-altitude cirrus. Plumes are apparent from fires burning near the California-Mexico border, San Diego, Camp Pendleton, the foothills of the San Bernardino Mountains, and in and around Simi Valley. The majority of the smoke is coming from the fires near San Diego and the San Bernardino Mountains.The Multiangle Imaging Spectro Radiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82o north and 82o south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 20510. The panels cover an area of 329 kilometers x 543 kilometers, and utilize data from blocks 62 to 66 within World Reference System-2 path 40.MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

  17. Geopolitica, economia y solidaridad internacional en la nueva cooperacion Sur-Sur: el caso de la Venezuela Bolivariana y PETROCARIBE

    National Research Council Canada - National Science Library

    Benzi, Daniele; Zapata, Ximena

    2013-01-01

    .... Se plantea que la emergencia de esta propuesta, al igual que otras iniciativas de cooperacion Sur-Sur, esta claramente vinculada a objetivos estrategicos de politica exterior que remiten basicamente...

  18. Divagations sur champ pénal (mars 2004)

    OpenAIRE

    Christian Demonchy

    2007-01-01

    En droit, la divagation d'un animal domestique est le fait que la personne responsable de cet animal le laisse errer sur la voie publique ou sur les biens d'autrui. Les divagations sur champ pénal sont-elles répréhensibles ?

  19. Gestion des agroecosystemes sur le mont agou en zone forestiere ...

    African Journals Online (AJOL)

    L'étude est une contribution à la connaissance du mode de gestion des paysages agraires par les populations locales sur le Mont Agou en zone forestière sur l'Atakora au Togo. Les pratiques agricoles sont fondées sur des conceptions des paysans pour un double objectif : assurer des revenus permanents et garantir une ...

  20. Teale California shoreline

    Data.gov (United States)

    California Department of Resources — California Spatial Information System (CaSIL) is a project designed to improve access to geo-spatial and geo-spatial related data information throughout the state of...

  1. California Condor Critical Habitat

    Data.gov (United States)

    California Department of Resources — These Data identify (in general) the areas where critical habitat for the California Condor occur. Critical habitat for the species consists of the following 10...

  2. N.3274 law project allowing the approbation of the agreement between the France and the United States of Mexico on the self development mechanism in the framework of the Kyoto protocol; N.3274 projet de loi autorisant l'approbation de l'accord entre la France et les Etats-Unis du Mexique sur le mecanisme de developpement propre dans le cadre du protocole de Kyoto

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-08-15

    The objectives of this agreement is to facilitate the elaboration and the implementing of greenhouse gases emissions reduction projects at Mexico associated to french institutions and allowing the contribution to the sustainable development in Mexico. The twelve articles of the agreement are presented. (A.L.B.)

  3. Environmental history of the dry forest biome of Guerrero, Mexico, and human impact during the last c. 2700 years

    NARCIS (Netherlands)

    Berrio, J.C.; Hooghiemstra, H.; van Geel, B.; Ludlow-Wiegers, B.

    2006-01-01

    Two lake sediment cores from Madre del Sur mountain range, Guerrero State, west-central Mexico were studied to examine the past dynamics of the dry forest biome. Pollen, spores of coprophilous fungi, cyanobacteria and lithological changes are presented. The 390-cm Tixtla core (17°30′N, 99°24′W, 1400

  4. New Mexico Parks

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This dataset provides an initial version of the locations of parks in New Mexico, in point form, with limited attributes, compiled using available data from a...

  5. New Mexico Ghost Towns

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This data provides locations and non-spatial attributes of many ghost towns in the State of New Mexico, compiled from various sources. Locations provided with...

  6. New Mexico National Cemeteries

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The United States Department of Veterans Affairs National Cemetery Administration maintains 2 national cemeteries in the state of New Mexico; the Fort Bayard...

  7. New Mexico State Parks

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This dataset provides an initial version of the generalized physical boundaries of New Mexico State Parks, in polygonal form with limited attributes, compiled using...

  8. Note sur le post-Taylorisme

    OpenAIRE

    Barrier, Christiane

    1994-01-01

    International audience; Cet article revient sur deux anciens numéros de la revue Sociologie du travail en partie consacrés au post-taylorisme, et avance l'idée d'une insuffisance de l'épistémologie sociologique chez les sociologues du travail français.

  9. Impact of the 2015 El Niño-Southern Oscillation on the Abundance and Foraging Habits of Guadalupe Fur Seals and California Sea Lions from the San Benito Archipelago, Mexico

    Science.gov (United States)

    Elorriaga-Verplancken, Fernando R.; Sierra-Rodríguez, Gema E.; Rosales-Nanduca, Hiram; Acevedo-Whitehouse, Karina; Sandoval-Sierra, Julieta

    2016-01-01

    The abundance of California sea lions (Zalophus californianus) (CSLs) and Guadalupe fur seals (Arctocephalus philippii townsendi) (GFSs) from the San Benito Archipelago (SBA) was determined through nine monthly surveys in 2014–2015. Assessment of their foraging habits was examined based on the isotopic analysis of pups (maternal indicators) (SIAR/SIBER-R). Environmental variability between 2014 and 2015 was also analyzed, in terms of sea surface temperature (SST) and chlorophyll (Chl-a) concentration. Both otariids reached their highest abundance in July of both years; however, relative to 2014, the 2015 survey showed a 59.7% decline in the total GFS abundance and a 42.9% decrease of GFS pups, while total CSL abundance decreased 52.0% and CSL pup presence decreased in 61.7%. All monthly surveys for both otariids showed a similar trend (>50% decrease in 2015). Compared to 2014, the 2015 GFSs isotopic niche was three times larger (2.0 in 2015, 0.6 in 2014) and the δ13C was significantly lower. CSLs also showed significantly lower δ13C and higher δ15N in 2015. Interannual segregation was greater for CSLs, and their pup body mass was also significantly lower during the 2015 breeding season (mean = 8.7 kg) than in the same season of 2014 (mean = 9.9 kg). The decrease in δ13C for both otariids reflected a more oceanic foraging; most likely associated with the decline in primary productivity in surrounding areas to the SBA, related to a higher SST caused by the 2015 ENSO, with a subsequent increase in foraging effort. These would explain the fewer observed individuals on land, especially pups, which showed diminished body condition (CSLs). This study highlights the importance of marine mammals as sentinel species that respond dynamically to changes in environment, providing valuable information on the effect of ENSO on pinnipeds in Mexican waters. PMID:27171473

  10. Étude du Partenariat de recherche sur l'influenza aviaire en Asie sur ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Étude du Partenariat de recherche sur l'influenza aviaire en Asie sur l'efficacité des mesures de lutte. L'influenza aviaire hautement pathogène (H5N1) est une grave maladie qui touche la volaille et contamine les êtres humains dans une faible proportion. L'Organisation mondiale de la santé croit que le virus pourrait subir ...

  11. Impact du revêtement sur le comportement à l'usure et sur la ...

    African Journals Online (AJOL)

    Impact du revêtement sur le comportement à l'usure et sur la rugosité de la surface usinée en fraisage frontal de l'acier C18. Mohieddine Benghersallah et Lakhdar Boulanouar. Laboratoire Mécanique des Matériaux et Maintenance Industrielle (LR3MI),. Département de Génie Mécanique,. Université Badji Mokhtar, BP12, ...

  12. Psychology in Mexico

    Science.gov (United States)

    Ruiz, Eleonora Rubio

    2011-01-01

    The first formal psychology course taught in Mexico was in 1896 at Mexico's National University; today, National Autonomous University of Mexico (UNAM in Spanish). The modern psychology from Europe and the US in the late 19th century were the primary influences of Mexican psychology, as well as psychoanalysis and both clinical and experimental…

  13. The Impact of Resource Scarcity on Bonding and Bridging Social Capital: the Case of Fishers' Information-Sharing Networks in Loreto, BCS, Mexico

    Directory of Open Access Journals (Sweden)

    Saudiel Ramirez-Sanchez

    2009-06-01

    Full Text Available Fishers often rely on their social capital to cope with resource fluctuations by sharing information on the abundance and location of fish. Drawing on research in seven coastal fishing communities in Loreto, Baja California Sur, Mexico, we examine the effect of resource scarcity on the bonding, bridging, and linking social-capital patterns of fishers' information-sharing networks. We found that: (1 fishers' information sharing is activated in response to varying ecological conditions; (2 resource scarcity is an ambiguous indicator of the extent to which fishers share information on the abundance and location of fish within and between communities; (3 information sharing is based on trust and occurs through kinship, friendship, and acquaintance social relations; (4 friendship ties play a key and flexible role in fishers' social networks within and between communities; (5 overall, the composition of fishers' social networks follows a friendship>kinship>acquaintance order of importance; and (6 the function of social ties, internal conflict, and settlement histories moderate the effects of resource scarcity on fishers' social capital. We conclude by arguing that the livelihoods of fishers from Loreto have adaptive capacity for dealing with fish fluctuations but little or no proactive resilience to address resource-management issues.

  14. The key host for an invasive forest pathogen also facilitates the pathogen’s survival of wildfire in California forests

    Science.gov (United States)

    Maia M. Beh; Margaret R. Metz; Kerri M. Frangioso; David M. Rizzo

    2012-01-01

    SummaryThe first wildfires in sudden oak death-impacted forests occurred in 2008 in the Big Sur region of California, creating the rare opportunity to study the interaction between an invasive forest pathogen and a historically recurring disturbance.To determine whether and how the sudden oak death...

  15. The Cooperativism and Agricultural Credit in Baja California, Mexico (1930-1950: A first approach El cooperativismo y la financiación agrícola en Baja California, México (1930-1950: Una aproximación inicial

    Directory of Open Access Journals (Sweden)

    Jesús Méndez Reyes

    2011-01-01

    Full Text Available In order to the neoclassic conventional theory the operation of the credit markets face two basic difficulties: the asymmetric or imperfect information and the adverse selection of the borrower come together with the nonpayment risk. On and other side, more heterodox, the collectivism, the social capital and the creation of informal nets and credit societies, use to low down the transaction costs related to the financing problem. This kind of organization makes easier the development of cooperativism in economy. In México, after the Revolution and the establishment of an authoritarian political and vertical regimen, the cooperativism became one of the referents of the rural organization in order to get credit of private and public banks. In the northeast of the country and Baja California peninsula, the existence of fishing, cattle raising, farming and transportation cooperatives means a blunt of economical activity and one of the channels of development in the zone. The purpose of this article is to shape what kind of cooperativism was set up in the Northern District of Baja California and what type of relation kept with the national cooperative movement between 1930 and 1950.Para la teoría neoclásica convencional el funcionamiento de los mercados de crédito soporta dos dificultades básicas: la información imperfecta o asimétrica y la selección adversa del prestatario aunada al riesgo del no pago. En el otro extremo, más heterodoxo, el colectivismo, el capital social y la formación de redes informales y sociedades de crédito suelen reducir los costes de transacción ligados al problema de la financiación. Este tipo de organización facilita el desenvolvimiento del cooperativismo en la economía. En México, después de la Revolución y la conformación de un régimen político autoritario y vertical, el cooperativismo se constituyó en uno de los referentes de la organización campesina para conseguir crédito de la banca pública y

  16. Equinodermos (Echinodermata) del Golfo de California, México

    OpenAIRE

    Solís-Marín, Francisco A.; Laguarda-Figueras, Alfredo; Durán-González, Alicia; Ahearn, Cynthia Gust; Torres Vega, Juan

    2016-01-01

    Echinoderms (Echinodermata) from the Gulf of California, Mexico. A systematic list of the echinoderms of the Gulf of California, based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. A total of 193 echinoderm species is recorded, distributed in 108 genera, 51 families and 19 orders. 12 new records...

  17. An extirpated lineage of a threatened frog species resurfaces in southern California

    Science.gov (United States)

    Backlin, Adam R.; Richmond, Jonathan Q.; Gallegos, Elizabeth; Christensen, Clinton K.; Fisher, Robert N.

    2017-01-01

    Southern California has experienced widespread amphibian declines since the 1960s. One species, the Vulnerable California red-legged frog Rana draytonii, is now considered to be extirpated from most of southern California. In February 2017 a population of R. draytonii was discovered in the southern foothills of the San Bernardino Mountains of Riverside County, California, near the edge of the species’ historical distribution. This population belongs to an mtDNA lineage that was presumed to be extirpated within the USA but is still extant in Baja California, Mexico. This discovery increases the potential for future, evolutionarily informed translocations within the southern portion of this species’ range in California.

  18. Relaciones científicas de medicina veterinaria venezolana con sus pares latinoamericanos: México y el Cono Sur (1933-1955 Scientific links between Venezuela's veterinary medicine and its Latin American counterparts: Mexico and the Southern Cone (1933-1955

    Directory of Open Access Journals (Sweden)

    Yajaira Freites

    2008-06-01

    Full Text Available En este trabajo se describe como las relaciones entre Venezuela, Argentina, Uruguay y México se vincularon a la construcción de una capacidad endógena del primero en el campo de la medicina veterinaria. La influencia de los países en cuestión ocurre en diversas etapas del crecimiento de la comunidad de veterinarios en Venezuela. El artículo expone una experiencia de como las relaciones científico-técnicas no siempre proceden según el esquema centro-periferia (sociedad desarrollada a periférica, sino que pone en evidencia la existencia de sociedades periféricas que pueden actuar como referentes o intermediarios para la transferencia de los saberes.The bonds established by Venezuela from 1933 to 1955 with Argentina, Uruguay and Mexico formed the groundwork for the Venezuelan State's efforts to foster knowledge and skills in the field of veterinary medicine. The countries in question exerted an influence at different stages in the growth of the veterinary community in Venezuela. This study describes an experience of how scientific and technical ties are not always forged along center-periphery lines, showing that there are peripheral societies capable of operating as points of reference or intermediaries in the transfer of knowledge.

  19. Sloughed skin: a method for the systematic colletion of tissue samples from Baja California blue whales

    OpenAIRE

    Gendron, Diane; Mesnick, S.L.

    2001-01-01

    The frequency of occurrence of naturally sloughed skin was investigated to verify the feasibility of this method to study blue whale genetics off Baja California. Sloughed skin was recorded in 97% of 337 surfacing intervals with blue whales, Balaenoptera musculus, along the Baja California peninsula, Mexico. No significant difference (P>0.05) was found in size of pieces of skin sloughed from whales in different habitats, sea surface temperatures or whether they were alone or in pairs. Samp...

  20. Narcomundo: How Narcotraficantes Gained Control of Northern Mexico and Beyond, 1945-1985

    OpenAIRE

    Hernandez, Carlos Armando

    2015-01-01

    Mexico’s official history does not properly address the Drug Wars and its effect on the nation as well as the U.S. – Mexico border region, including criminal spillover between the two countries especially since 1911. Drawing from evidence gathered at Mexico’s National Archives – specifically declassified documents from Mexico’s secret police files – contemporary news accounts from Tijuana, Mexico City, and California, as well as court cases and long ignored political biographies, I trace the...

  1. N.3663 report realized for the Foreign Affairs Commission on the law project n. 3274, authorizing the approbation of the agreement between France and United States of Mexico on the mechanism of clean development in the framework of the Kyoto protocol; N. 3663 rapport fait au nom de la Commission des Affaires Etrangeres sur le projet de loi n. 3274, autorisant l'approbation de l'accord entre la France et les Etats-Unis du Mexique sur le mecanisme de developpement propre dans le cadre du protocole de Kyoto

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-02-15

    The clean development mechanism is one of the Kyoto protocol flexible mechanisms. It is intended to allow industrialized countries to offset their greenhouse gas reduction targets by funding projects in developing countries that lead to reduced emissions. In this framework, this law project aims to favor the cooperation between France and Mexico. The first part presents the advantages of the Kyoto protocol ane second part is devoted to the bilateral cooperation. (A.L.B.)

  2. Enquêtes sur les soucoupes volantes

    OpenAIRE

    Lagrange, Pierre

    2007-01-01

    La dispute autour du mot « preuve » se réduit à une question : Qu'est-ce qui constitue une preuve ? Faut-il qu'un ovni atterrisse à l'entrée du Pentagone, près des bureaux des chefs d'État-Major ? Ou bien est-ce une preuve quand une station de radar au sol détecte un ovni, envoie un jet l'intercepter, que le pilote du jet le voit et le suit sur son radar pour finir par le voir disparaître à une vitesse phénoménale ? Ou est-ce une preuve quand un pilote tire sur un ovni et maintient son histoi...

  3. Sur la proximité de Dieu.

    Directory of Open Access Journals (Sweden)

    Dominic Desroches

    2009-10-01

    Full Text Available Il n’est pas impertinent, quelque temps après la visite du pape en Terre sainte, de réfléchir à nouveaux frais sur la rencontre des trois grandes religions monothéistes (judaïsme, christianisme et islam et sur leur destin commun. Le moment est peut-être d’autant mieux choisi qu’on peut le faire aujourd’hui dans le sillage de Peter Sloterdijk, qui s’est livré, dès 2007, à ce genre d’exercice dans son ouvrage Gottes Eifer , traduit en français par Olivier Mannoni en 2008 ...

  4. Maintenance sur les infrastructures de surface

    CERN Document Server

    Chevret, P

    2000-01-01

    L'objet de ce document est de dresser le bilan de l'activité du Groupe Technical Facilities Management dans le domaine de la maintenance. Ce bilan couvre les activités techniques du génie civil, du chauffage-climatisation et de l'électricité, s'appliquant dans une large majorité au seul secteur tertiaire, tant sur le plan préventif que correctif. Les principaux paramètres indicateurs de l'activité sont situés dans leur évolution au cours des dernières années. Les auteurs abordent également les principaux projets complémentaires de maintenance, qui sont conduits pour maintenir l'état du patrimoine en dépit des restrictions budgétaires, faire face aux problèmes d'obsolescence, de défaillances récurrentes sur certains matériels, et satisfaire aux normes de sécurité. L'incidence positive de ces actions sur le nombre d'interventions de maintenance corrective est également montrée. Enfin, des perspectives de progrès sont dégagées, visant à une gestion davantage prévisionnelle de la ma...

  5. Controverses sur les sucres [Controversies about sugars

    Directory of Open Access Journals (Sweden)

    Malika BOUCHENAK

    2016-12-01

    Full Text Available La surconsommation de sucres ajoutés et leurs effets putatifs sur diverses pathologies cardiométaboliques continuent de susciter des controverses. Dans les années 1950, le taux élevé de maladies cardiovasculaires (MCV, chez les hommes Américains a conduit à des études sur le rôle des facteurs alimentaires, tels que le cholestérol, les phytostérols, l'excès de calories, les acides aminés, les graisses, les glucides, les vitamines et les minéraux, à influencer le risque de MCV. Dans les années 60, deux éminents physiologistes, plaidant pour des hypothèses causales divergentes de MCV, John Yudkin a identifié les sucres ajoutés comme agent primaire, tandis que Ancel Keys identifiait les graisses totales, les graisses saturées et le cholestérol alimentaire. Cependant, dans les années 80, peu de scientifiques croyaient que les sucres ajoutés jouaient un rôle important dans la maladie coronarienne, et les premiers conseils nutritionnels de 1980 (1980 Dietary Guidelines for americans étaient axés sur la réduction des graisses totales, des graisses saturées et du cholestérol alimentaire pour la prévention des MCV.

  6. Marine Spatial Planning in a Transboundary Context: Linking Baja California with California's Network of Marine Protected Areas

    Directory of Open Access Journals (Sweden)

    Nur Arafeh-Dalmau

    2017-05-01

    Full Text Available It is acknowledged that an effective path to globally protect marine ecosystems is through the establishment of eco-regional scale networks of MPAs spanning across national frontiers. In this work we aimed to plan for regionally feasible networks of MPAs that can be ecologically linked with an existing one in a transboundary context. We illustrate our exercise in the Ensenadian eco-region, a shared marine ecosystem between the south of California, United States of America (USA, and the north of Baja California, Mexico; where conservation actions differ across the border. In the USA, California recently established a network of MPAs through the Marine Life Protection Act (MLPA, while in Mexico: Baja California lacks a network of MPAs or a marine spatial planning effort to establish it. We generated four different scenarios with Marxan by integrating different ecological, social, and management considerations (habitat representation, opportunity costs, habitat condition, and enforcement costs. To do so, we characterized and collected biophysical and socio-economic information for Baja California and developed novel approaches to quantify and incorporate some of these considerations. We were able to design feasible networks of MPAs in Baja California that are ecologically linked with California's network (met between 78.5 and 84.4% of the MLPA guidelines and that would represent a low cost for fishers and aquaculture investors. We found that when multiple considerations are integrated more priority areas for conservation emerge. For our region, human distribution presents a strong gradient from north to south and resulted to be an important factor for the spatial arrangement of the priority areas. This work shows how, despite the constraints of a data-poor area, the available conservation principles, mapping, and planning tools can still be used to generate spatial conservation plans in a transboundary context.

  7. A new species of Cogia from Oaxaca, Mexico (Lepidoptera: Hesperiidae: Eudaminae).

    Science.gov (United States)

    Warren, Andrew D; Dolibaina, Diego R; Hernández-Mejía, Claudia

    2015-03-31

    A new species of Cogia A. Butler, 1870, is described from two localities ranging from 1470 to 2000 m elevation in the Sierra Madre del Sur of Oaxaca, Mexico; it occurs in cloud forest habitats and appears to be endemic to Mexico. Cogia buena, n. sp., is closely related to C. mala Evans, 1953 and C. aventinus (Godman & Salvin, 1894); these three species are the only known Cogia taxa whose males lack a hair tuft on the dorsal hindwing, and all have similar genitalia.

  8. Water use in California

    Science.gov (United States)

    Brandt, Justin; Sneed, Michelle; Rogers, Laurel Lynn; Metzger, Loren F.; Rewis, Diane; House, Sally F.

    2014-01-01

    As part of the USGS National Water Use Compilation, the California Water Science Center works in cooperation with local, State, and Federal agencies as well as academic and private organizations to collect and report total water withdrawals for California. The 2010 California water use data are aggregated here, in this website, for the first time. The California Water Science Center released these data ahead of the online USGS National Water Use Compilation circular report, in response to increased interest associated with current drought conditions. The national report is expected to be released late in 2014. The data on this website represents the most current California water use data available in the USGS National Water Use Compilation. It contains a section on water use in California for 2010. Water-use estimates are compiled by withdrawal source type, use category, and county. Withdrawal source types include groundwater, both fresh and saline,

  9. Agua Milpa powers Mexico`s industrialization

    Energy Technology Data Exchange (ETDEWEB)

    Norden, Friedrich [Siemens AG Unternehmensbereich KWU, Erlangen (Germany)

    1995-06-01

    With the establishment of the new free trade area in the United States, Canada and Mexico, it is anticipated that a new industrial zone will develop in Northern Mexico, near to the U.S. border. To meet the resulting power demand, various projects, including the Agua Milpa hydroelectric power plant scheme, have been initiated. The planning, construction and commissioning of the plant, which has a total capacity of 3 x 341 MVA, is described. (UK)

  10. Dental education in Mexico.

    Science.gov (United States)

    Masuoka, David; Komabayashi, Takashi; Reyes-Vela, Enrique

    2014-06-01

    The aim of this article is to provide information about dental education in Mexico, including its history, the dental school system, curriculum and dental licensure. In 1977, there were only 59 Mexican dental schools; however, there were 83 schools registered in the last official national count in 2007. Forty-one dental schools are public, and the other 42 are private. Every year the number of private dental schools increases. Admission to dental schools in Mexico requires a high school diploma. All classes are conducted in Spanish. To obtain licensure in Mexico, dental students must complete a 3 to 5-year program plus a year of community service. No formal nationwide standard clinical/didactic curriculum exists in Mexico. There are approximately 153,000 dentists in Mexico, a number that increases each year. The dentist-patient ratio is approximately 1:700. However, the high percentage of inactive licensed dentists in Mexico points to a serious problem.

  11. Southern California Particle Center

    Data.gov (United States)

    Federal Laboratory Consortium — At the Southern California Particle Center, center researchers will investigate the underlying mechanisms that produce the health effects associated with exposure to...

  12. Organic Beekeeping in Mexico

    OpenAIRE

    Garibay, Salvador; Gänz, Peter; Vandame, Rémy

    2010-01-01

    Mexico is often described as a cornucopia, a land with high diversity in ecosystems, crops, fauna and flora. These are superb preconditions for organic honey production. Already the pre-hispanic Maya cultures produced honey from the native stingless bee (Meliponini) before the Spanish introduced European honey bee (Apis mellifera L). The main beekeeping product in Mexico is honey. Mexico ranks sixth in the world in honey production (57,000 t) and third as an exporter (25,000 t). Two condit...

  13. SeaWiFS: The Western United States and Mexico

    Science.gov (United States)

    2002-01-01

    The linear patterns in the clouds over the Pacific suggest contrail origins. Subtle variations in cloud density reveal vortex street downwind (southeast) of Mexico's Guadalupe Island. The Great Salt Lake in Utah is divided into two very different colored bodies of water by a railroad causeway. The southern Gulf of California continues to bloom brightly. Credit: Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  14. El (los Sur buscando al Sur. Una construcción entre estereotipos y realidad.

    Directory of Open Access Journals (Sweden)

    Mabel Franzone

    2010-11-01

    Full Text Available Todas las lecturas que podamos hacer del Sur, de sus propias representaciones, de aquellas vehiculizadas por el Norte, de sus creaciones, de sus reacciones, de su búsqueda constante de identidad, son lecturas de múltiples situaciones, que llaman a cruces insoslayables entre pueblos, entre distintas etnias, entre disciplinas, entre sentimientos que van desde el rechazo hasta la atracción casi magnética entre los dos hemisferios. Nuestra intención primera era la de reunir de manera aproximativa las problemáticas actuales de los Sur, ligadas a lo imaginario.

  15. El renovado auge de la Cooperación Sur-Sur : La experiencia iberoamericana

    OpenAIRE

    Xalma, Cristina

    2013-01-01

    El presente artículo revisa y caracteriza el renovado auge que la Cooperación Sur-Sur ha experimentado en los últimos años a partir de una experiencia concreta: la protagonizada por los países miembros de la Conferencia Iberoamericana y, en particular, por los diecinueve latinoamericanos de habla española y portuguesa (desde México hasta Chile, incluyendo a Cuba y República Dominicana), más España y Portugal. Busca entender una cooperación que crece y se expande bajo distintas fórmulas y dime...

  16. Regroupement des statistiques sur le secteur des TIC et analyse ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Regroupement des statistiques sur le secteur des TIC et analyse axée sur les politiques. La présence et l'influence des technologies de l'information et de la communication (TIC) continuent de s'élargir et de s'accroître, tout comme leurs répercussions sur le développement économique. Toutefois, il reste encore beaucoup ...

  17. [Mexico and Japanese emigrants].

    Science.gov (United States)

    Yanaguida, T; Akagui, T

    1995-08-01

    "Japanese immigration to Mexico began in the last decade of the 19th century with a coffee growing project, and proved a failure. Subsequent attempts [at] sending contract labor migrants by emigration agencies, which involved 10,000 Japanese emigrants in 1901-1908, were also unsuccessful, and Mexico turned for Japanese emigrants into a short step on their way to the United States. The evolution of those who remained in Mexico and the different developments of the Japanese communities in Mexico [are] analyzed here until the period after World War II." (SUMMARY IN ENG) excerpt

  18. Sandia National Laboratories and higher education in New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Fairbanks, R.R.

    1990-03-01

    New Mexico education institutions have had an extraordinary influence on the Sandia workforce throughout the years. Today, our approximately 8400 employees hold 2028 graduate and undergraduate degrees from the 4-year colleges and universities in the state. This accounts for 22.3% of the degrees held by Sandia employees. Employees also hold another 618 2-year degrees from New Mexico educational institutions. The total number of degrees is nearly twice the number from the next leading state, California. When only the highest degree held by an employee is considered, that degree (PhD, master, or bachelor's) came from a New Mexico college or university 29% of the time. Employees whose highest degree is from the University of New Mexico (UNM) rank, in numbers, at the top of most categories of management and staff at Sandia Albuquerque. UNM, with its proximity to our headquarters in Albuquerque, has granted the most degrees to Sandia employees. Employees also hold degrees from New Mexico State University (NMSU). New Mexico Institute of Mining Technology (NMIMT), and from other 4-year regional institutions in the state. Engineering degrees and degrees in business are the most numerous, although employees hold degrees in many other fields, reflecting the diversity of work being done at the Laboratories by graduates of colleges and universities in the state. For more detailed information, refer to Appendix A. 4 figs., 11 tabs.

  19. En California dos pioneros: Uno en el pasado y otro en el presente

    OpenAIRE

    Mauricio Bermúdez

    2002-01-01

    Agost on Haraszthy buscando un clima para alivio de su enfermedad arribó en 1849 al sur de California donde se convirtió en el pionero al importar, sembrar y producir vino con Zinfandel, una entre otras muchas vides europeas. Construyó el viñedo Buena Vista diseñado para esa época con las mejores facilidades, no obstante, la empresa estaba destinada al colapso financiero por el incumplimiento del Estado de California; la vida de Agost on fue una aventura y tras su muerte una leyenda. En 1976 ...

  20. Results of an injection test using ethyl alcohol as tracer at Los Humeros geothermal field, Puebla, Mexico; Resultados de una prueba de inyeccion de alcohol empleado como trazador, en el campo geotermico de Los humeros, Puebla, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Tovar Aguado, Rigoberto; Lopez Romero, Oscar [Comision Federal de Electricidad, Los Humeros, Puebla (Mexico)

    2000-12-01

    Los Humeros is the third Mexican geothermal field where ethyl alcohol was used as organic tracer to test communication between wells. The first Mexican geothermal field where this kind of test was used Los Azufres, Michoacan. The second was Las Tres Virgenes, Baja California Sur. In both cases, connections between wells were observed. The injection well H-29 is in the north-central sector of Los Humeros geothermal field, Puebla, Mexico. At a depth of 1580 meters, 600 liters of ethyl alcohol was pumped through a 60.35 mm (23/8 inch) diameter tube after 2.7 m{sup 3} of geothermal fluids were displaced, allowing the alcohol to reach the formation. Then, the normal injection process continued with water and condensed steam (130 t/h). On the basis of the experience acquired with similar tests conducted at Las Tres Virgenes geothermal field, and with the goal of detecting the tracer, samples of condensed steam were collected in nearby wells (H-15, H-16, H-17, H-30, H-33, H-36 and H-8) and in distant wells-named special samples (H-32, H-1, H-11, H-12, H-19, H-20, H-35, H-37, H-39, H-6 and H-9). Condensed steam samples were collected every 12 hours, the every week and finally every 15 days, making a total of 592 samples. The chemical analysis were done in two stages because of probable with the chromatograph. In the first stage, 441 samples were run and the rest were run in the second stage. No evidence of the tracer was observed in the monitoring wells. The results confirm the existence of a low-to-moderate permeability, as was previously interpreted using pressure log data. [Spanish] Los Humeros es el tercer campo geotermico de Mexico en el que se realiza una prueba de trazadores organicos empleando alcohol etilico con la finalidad principal de conocer si existe comunicacion entre pozos. El primer campo geotermico en el que se realizo esta prueba fue el de Los Azufres, Michoacan y el segundo el de Las Tres Virgenes, Baja California Sur; en ambos casos se encontro

  1. Le port d’Acapulco, escale sur le chemin de l’Asie

    OpenAIRE

    Tempère, Delphine

    2016-01-01

    Acapulco joue à l’époque coloniale un rôle déterminant entre l’Asie, l’Amérique et l’Espagne ; c’est une escale obligatoire sur le chemin de l’Asie, c’est le port asiatique de l’Amérique. De Séville à Veracruz, des côtes mexicaines à Mexico, de la capitale de la Nouvelle Espagne à Acapulco, les informations, les marchandises et les hommes circulent afin de rejoindre les Philippines. Acapulco est en effet le seul port autorisé en Amérique afin de se rendre à Manille grâce à la liaison maritime...

  2. Economic restructuring plan and emergent regions: Baja California, 1980-1995

    Directory of Open Access Journals (Sweden)

    Arturo Ranfla González

    2000-07-01

    Full Text Available The aim of this essay is to foster a discussion on the political and territorial levels that are involved in the process of economic globalization of the Northern border region of Mexico, and particularly the state of Baja California. For such purpose, an approach is taken on the economic and sectorial conditions of the Baja California economy during the 1981-1994 period. Also, a detailed analysis of the sectorial structure and dynamics of production —during that same period— of the main municipalities is Baja California in order to identify the profiles and hierarchy of each of them is carried out.

  3. Self-medication practices in two California Mexican communities.

    Science.gov (United States)

    Pylypa, J

    2001-04-01

    Although social scientists have taken up the study of medication use in both developing and developed nations, the medication practices of immigrants remain largely unstudied. In this study, qualitative research was employed in order to describe and compare self-medication practices in two California Mexican immigrant groups: families living along the border near Tijuana, Mexico, and migrant farm worker families residing in illegal encampments and substandard housing in San Diego's North County. Medication and health seeking practices were found to vary according to the specific political-economic, sociocultural, and geographic contexts in which different subpopulations of California Mexicans live. The California-Mexico border area was examined as an important context for considering self-medication behaviors, since it permits border-crossing into Tijuana for the purpose of buying Mexican pharmaceuticals at low cost without a prescription. The popularity of injections among California Mexicans and the cross-border purchasing of injectable antibiotics and vitamins are discussed as issues of particular relevance for immigrants living along the border.

  4. Understanding Climate Change on the California Coast: Accounting for Extreme Daily Events among Long-Term Trends

    Directory of Open Access Journals (Sweden)

    Christopher Potter

    2014-02-01

    Full Text Available The majority of weather station records indicate that surface air temperatures have been warming in California between 1950 and 2005. Temperature data from the mid-1990s to the present were analyzed for stations on California Central Coast near Big Sur (Monterey County to better understand potential for climate change in this biologically unique region. Results showed that daily temperatures in both the winter and summer seasons have cooled the Big Sur coast, particularly after 2003. A current hypothesis is that observed coastal California cooling derives from greenhouse gas-induced regional warming of the inland Central Valley and Sierra Nevada foothill areas, resulting in stronger sustained on-shore sea-breeze flow. Closer examination of daily temperature records at a station location near the Big Sur coast revealed that, even as average monthly maximum temperatures (Tmax have decreased gradually, the number of extreme warm summer days (Tmax > 37 °C has also increased by several fold in frequency. Overall patterns in the station records since the mid-1990s indicated that diurnal temperature ranges are widening on the Big Sur coast, with markedly cooler nighttime temperatures (frequently in the wet winter season followed by slightly higher-than-average daytime temperatures, especially during the warm, dry summer season.

  5. Effets de la réglementation du marché du travail sur la situation sur ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Effets de la réglementation du marché du travail sur la situation sur le marché et sur la répartition des revenus en Colombie et au Chili ... plus en plus ces inégalités aux changements majeurs que connaît la demande en main-d'oeuvre dans un contexte de restructuration économique et d'ouverture aux marchés mondiaux.

  6. Cooperación SurSur: Regionalismos e integración en América Latina. Bruno Ayllon; Tahina Ojeda; Javier Surasky

    OpenAIRE

    Solano-Mercado, Ixhel; Benemérita Universidad Autónoma de Puebla (BUAP), México.

    2015-01-01

    Review of the book "Cooperación SurSur: Regionalismos e integración en América Latina" by Bruno Ayllon; Tahina Ojeda; Javier Surasky Reseña del libro "Cooperación SurSur: Regionalismos e integración en América Latina" escrito por Bruno Ayllon; Tahina Ojeda; Javier Surasky.

  7. Spain: Europe's California.

    Science.gov (United States)

    Wilvert, Calvin

    1994-01-01

    Contends that, as Spain integrates into the European Economic Community, it is considered to be Europe's California. Asserts that making regional comparisons between California and Spain can be an effective teaching method. Provides comparisons in such areas as agriculture and tourism. (CFR)

  8. California-Baja California border master plan - plan maestro fronterizo California-Baja California : executive summary.

    Science.gov (United States)

    2008-09-01

    Crossborder travel at the six land ports of entry (POEs) in the California-Baja California region has grown : significantly over the years. The San Diego County-Tijuana/Tecate region is home to the San Ysidro- : Puerta Mxico, the Otay Mesa-Mesa de ...

  9. California-Baja California border master plan - plan maestro fronterizo California-Baja California.

    Science.gov (United States)

    2008-09-01

    Crossborder travel at the six land ports of entry (POEs) in the California-Baja California region has grown : significantly over the years. The San Diego County-Tijuana/Tecate region is home to the San Ysidro- : Puerta Mxico, the Otay Mesa-Mesa de ...

  10. California's Reference Crisis.

    Science.gov (United States)

    Childers, Thomas A.

    1994-01-01

    Social and economic issues affecting the vitality of public libraries in California are discussed. A 1993 study by the California State Library identified diminishing reference skills and reference collections, reduced funding which impacted staffing, increased demand, technology change, and language/culture issues as contributing factors to…

  11. The northward march of summer low cloudiness along the California coast

    Science.gov (United States)

    Clemesha, Rachel E. S.; Gershunov, Alexander; Iacobellis, Sam F.; Williams, A. Park; Cayan, Daniel R.

    2016-02-01

    A new satellite-derived low cloud retrieval reveals rich spatial texture and coherent space-time propagation in summertime California coastal low cloudiness (CLC). Throughout the region, CLC is greatest during May-September but has considerable monthly variability within this summer season. On average, June is cloudiest along the coast of southern California and northern Baja, Mexico, while July is cloudiest along northern California's coast. Over the course of the summer, the core of peak CLC migrates northward along coastal California, reaching its northernmost extent in late July/early August, then recedes while weakening. The timing and movement of the CLC climatological structure is related to the summer evolution of lower tropospheric stability and both its component parts, sea surface temperature and potential temperature at 700 hPa. The roughly coincident seasonal timing of peak CLC with peak summertime temperatures translates into the strongest heat-modulating capacity of CLC along California's north coast.

  12. Economic geology, Mexico

    National Research Council Canada - National Science Library

    Salas, Guillermo P

    1991-01-01

    .... The various elements of Mexico's economic geology are discussed in the chapters of this volume by outstanding Mexican geologists, whose expertise vouches for the high quality of this presentation. Their efforts are a valuable contribution to the knowledge of Mexico's nonrenewable resources.

  13. Actinides detection in the Pacific Coast of Mexico; Deteccion de actinidos en el Litoral Pacifico de Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ordonez R, E.; Almazan T, M. G.; Cruz C, G. J.; Ramirez S, R., E-mail: eduardo.ordonez@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2013-10-15

    In this work is evaluated the activity of the alpha emitters, uranium and plutonium, in sand samples and seawater coming from diverse points of the Mexican Pacific Coast (Baja California, Jalisco, Colima and Guerrero). The used techniques were: radiochemistry separation and alpha spectrometry, with these techniques could be observed that the sand contains natural uranium and trace quantities of {sup 239}Pu and {sup 240}Pu combinations. The biggest activity in Pu was found in Finisterra, Baja California Sur (0.13 Bq/kg) and the minor (0 Bq/kg) in Miramar, Colima. The relationship between the geographical localization and the Pu activity suggests that while there is more interaction of the site with the oceanic currents, more is the content of Pu in the sands of the coast. (Author)

  14. Investissements directs étrangers au Maroc : impact sur la ...

    African Journals Online (AJOL)

    cette composante pour expliquer l'effet de l'IDE sur les performances d'une économie. ... investissements originaires des pays ayant un fort impact sur la performance ..... financier ;. • LnCF AP : le logarithme des dépenses de la consommation finale des administrations publiques en % du PIB comme mesure de la taille.

  15. TRITERPENE COMPOUNDS FROM THE LATEX OF FICUS SUR I ...

    African Journals Online (AJOL)

    Two pentacyclic triterpenoids of oleanane and ursene structures have been isolated from the latex of the Ficus sur. The compounds isolated from the latex are naturally acetylated in the 3-position and their structures have been elucidated on the basis of spectroscopic studies. KEY WORDS: Latex, Ficus sur, Moraceae, ...

  16. Dark humic alluvial paleosols in Central and Southern Mexico: Micromorphological indicators of Late Pleistocene megafauna habitats Paleosuelos aluviales con humus oscuro en el Centro y Sur de México: indicadores micromorfológicos de los hábitats de la megafauna del Pleistoceno tardío Paleosolos aluviais com húmus escuro no Centro e Sul do México: indicadores micromorfológicos dos habitats da megafauna do Pleistocénico tardio

    Directory of Open Access Journals (Sweden)

    Rosa E. Tovar

    2013-11-01

    Full Text Available During the Late Pleistocene, Mexico had a richer fauna than today with many different forms of megafauna that are now extinct. However, the ecosystems they inhabited and the particular ecological niches that they occupied are still poorly understood. Most of the findings of Pleistocene megafauna have been in alluvial deposits that present rich opportunities for paleoecological studies using paleopedological records. Floodplain paleosols commonly are poorly developed. However, micromorphological analysis provides information about the grade of development of the soil at a microscale, discriminating between genetic and sedimentary processes; thus helping in the identification of the environmental setting in which they formed. We analyzed the micromorphology of six pedogenetic units in the sequences of Santa Cruz Nuevo and Axamilpa, in the south of Puebla, and Huexoyucan, in the state of Tlaxcala. These pedosequences correspond to the second half of marine isotopic stage 3 (MIS3, MIS2 and the early Holocene. All studied units are characterized by strong pigmentation with dark humus. The micromorphological analysis of MIS3 paleosols reveals aquatic conditions with evidence of freshwater biota and microlamination as well as pedogenetic features of hydrogenic carbonate precipitation and redoximorphic processes. The dark paleosols of MIS2 and the early Holocene demonstrate signs of stronger coprogenic aggregation, weathering and fewer gleyic features. Comparison with modern soils shows that the latter were formed under better-drained, aerated conditions that exclude redoximorphic processes. We conclude that the dark colored Pleistocene paleosol units are indicative of different paleo-landscapes: wetlands in the MIS3 and moist meadows in MIS2 – early Holocene. The swampy ecosystems could play an important role as a megafauna habitat.En el Pleistoceno Tardío, México tenía una diversidad faunística más rica que en la actualidad, con diferentes

  17. Mexico's New Braceros: How NAFTA Promotes Child Labor and Truancy in the Onion Fields of Mexicali.

    Science.gov (United States)

    Bacon, David

    1997-01-01

    Although NAFTA has proven profitable for U.S. growers who have relocated agricultural production to Mexico, it has helped create an economic crisis that has forced thousands of Mexican children to leave school in order to work and supplement their parents' shrinking income. In Mexicali Valley (Baja California), approximately a fourth of the…

  18. Family Language Policy, Transnationalism, and the Diaspora Community of San Lucas Quiavini of Oaxaca, Mexico

    Science.gov (United States)

    Perez Baez, Gabriela

    2013-01-01

    San Lucas Quiavini is a community of Zapotec (Otomanguean) speakers in Oaxaca, Mexico. Since the 1970s, the community has seen large-scale migration to Los Angeles, California, where about half the community now resides. Participant observation and interviews conducted over nine years in both locales, with a focus on interactional patterns in the…

  19. Adolescence et pornographie sur la toile

    Science.gov (United States)

    Haza, Marion

    2012-01-01

    Dans cet article, nous abordons la question de l’accès à la pornographie sur Internet par les adolescents. Nous déclinons plusieurs facettes de ces rencontres: la rencontre «fortuite», quand les adolescents sont confrontés à des images intempestives, des publicités ou spams avec des contenus pornographiques; la rencontre «spectatrice», quand les adolescents cherchent activement des vidéos ou photos mettant en scène la sexualité; et enfin la rencontre «actrice», quand les adolescents se mettent en scène eux-mêmes, seuls ou à plusieurs, de façon pornographique sur le Net. A partir d’exemple, nous réfléchissons aux enjeux de ces rencontres virtuelles précoces de la sexualité adulte par rapport au développement adolescent et à la représentation de leur propre sexualité en construction. PMID:22876261

  20. Geothermal development of the Salton Trough, California and Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, T.D.; Howard, J.H.; Lande, D.P. (eds.)

    1975-04-01

    A geological description is given of the Salton Trought followed by a chronological history of attempts to exploit the area's geothermal resources. In addition, detailed descriptions are given of all ongoing geothermal projects in the area and the organizations conducting them.

  1. A missing piece in the puzzle: the presence of Euglossa viridissima in the Baja California Peninsula (Hymenoptera, Apidae

    Directory of Open Access Journals (Sweden)

    Armando Falcón-Brindis

    2018-01-01

    Full Text Available Orchid bees are a conspicuous component of the neotropical bee fauna, with a few species reaching the northernmost natural distribution for the group in northwestern continental Mexico. Among them, Euglossa viridissima Friese is here reported for the first time in the Cape Region of the Baja California peninsula, Mexico, where no species of the group have been found previously. These records are presented, their biogeographical implications discussed, and some interpretations of the local factors that influence the bees is presented.

  2. Eruption and magma crystallization ages of Las Tres Vírgenes (Baja California) constrained by combined 230Th/ 238U and (U-Th)/He dating of zircon

    Science.gov (United States)

    Schmitt, Axel K.; Stockli, Daniel F.; Hausback, Brian P.

    2006-11-01

    Las Tres Vírgenes volcano is a calc-alkaline composite cone located near the main Gulf of California escarpment on the E coast of the Baja California peninsula. High-sensitivity ion microprobe U-series ( 230Th/ 238U) ages for zircon from La Vírgen tephra average 121 - 10 + 12 ka (1σ; MSWD = 2.7), with discrete age peaks at ˜ 100 and 160 ka. The noble gas mass spectrometric (U-Th)/He zircon age, corrected for disequilibrium and pre-eruptive storage, is 36 ± 3 ka. This result for the eruption age of La Vírgen tephra is significantly older than previously postulated historic or Holocene ages that were based on an 18th century map reference and 14C dating of accidental charcoal, respectively. The new (U-Th)/He zircon age is consistent with a > 26 ± 4 ka age derived from cosmogenic He exposure dating of an overlying basaltic lava flow [Hausback, B.P. and Abrams, M.J., 1996. Plinian eruption of La Virgen Tephra, Volcán Las Tres Virgenes, Baja California Sur, Mexico. Eos, Transactions, American Geophysical Union, 77(46, Suppl.): 813-814.]. U-Pb zircon analysis of ignimbrites erupted from the adjacent Early Pleistocene La Reforma and El Aguajito calderas yielded ages of 1.38 ± 0.03 Ma ( n = 12; MSWD = 1.0) and 1.17 ± 0.07 Ma ( n = 23; MSWD = 1.3), respectively. No evidence for these ages is found among La Vírgen zircons, whereas pre-Quaternary zircon xenocrysts are common. The La Vírgen magma, therefore, evolved unrelated to Early Pleistocene magmatism in adjacent calderas, but assimilated local basement rocks. A gap between average Th-U and (U-Th)/He zircon ages suggests that zircon crystallization was discontinuous in the La Vírgen magma chamber. In addition, partial resorption of zircon suggests episodic thermal rejuvenation, most likely by basaltic recharge. Based on the zircon record, the > 100 ka lifetime of the thermal anomaly that sustained repeated intrusive pulses significantly exceeds the age of the last eruption. This strengthens the view that Tres

  3. Inventorying and Monitoring of Tropical Dry Forests Tree Diversity in Jalisco, Mexico Using a Geographical Information System

    Science.gov (United States)

    Efren Hernandez-Alvarez; Dieter R. Pelz; Carlos Rodriguez Franco

    2006-01-01

    Tropical dry forests in Mexico are an outstanding natural resource, due to the large surface area they cover. This ecosystem can be found from Baja California Norte to Chiapas on the eastern coast of the country. On the Gulf of Mexico side it grows from Tamaulipas to Yucatan. This is an ecosystem that is home to a wide diversity of plants, which include 114 tree...

  4. California Ocean Uses Atlas

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is a result of the California Ocean Uses Atlas Project: a collaboration between NOAA's National Marine Protected Areas Center and Marine Conservation...

  5. University of Southern California

    Data.gov (United States)

    Federal Laboratory Consortium — The focus of the University of Southern California (USC) Children''s Environmental Health Center is to develop a better understanding of how host susceptibility and...

  6. California Data Exchange Center

    Science.gov (United States)

    ... to make July &28;Water Smart Month.&29; &28;Conserving ... Remote sensors today indicate that statewide, snowpack water content is 54 percent of ... California ranked first, along with Texas, on ...

  7. Coastal California Digital Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This digital ortho-imagery dataset is a survey of coastal California. The project area consists of approximately 3774 square miles. The project design of the digital...

  8. Kelp distribution off California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set delineates kelp beds (Nereocystis leutkeana and Macrocystis spp.) along the Pacific Coast of California. Multiple years of kelp mapping data for the...

  9. California Harpoon Fishery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vessel logbook and landings data from harpoon vessels that fish within 200 miles of the California coast, from 1974 to present. The harpoon...

  10. Earthquakes in Southern California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — There have been many earthquake occurrences in Southern California. This set of slides shows earthquake damage from the following events: Imperial Valley, 1979,...

  11. California Watershed Hydrologic Units

    Data.gov (United States)

    California Department of Resources — This dataset is intended to be used as a tool for water-resource management and planning activities, particularly for site-specific and localized studies requiring a...

  12. Migration from Mexico to the United States: A high-speed cancer transition.

    Science.gov (United States)

    Pinheiro, Paulo S; Callahan, Karen E; Stern, Mariana C; de Vries, Esther

    2018-02-01

    Differences and similarities in cancer patterns between the country of Mexico and the United States' Mexican population, 11% of the entire US population, have not been studied. Mortality data from 2008 to 2012 in Mexico and California were analyzed and compared for causes of cancer death among adult and pediatric populations, using standard techniques and negative binomial regression. A total of 380,227 cancer deaths from Mexico and California were included. Mexican Americans had 49% and 13% higher mortality than their counterparts in Mexico among males and females, respectively. For Mexican Immigrants in the US, overall cancer mortality was similar to Mexico, their country of birth, but all-cancers-combined rates mask wide variation by specific cancer site. The most extreme results were recorded when comparing Mexican Americans to Mexicans in Mexico: with mortality rate ratios ranging from 2.72 (95% CI: 2.44-3.03) for colorectal cancer in males to 0.28 (95% CI: 0.24-0.33) for cervical cancer in females. These findings further reinforce the preeminent role that the environment, in its multiple aspects, has on cancer. Overall, mortality from obesity and tobacco-related cancers was higher among Mexican origin populations in the US compared to Mexico, suggesting a higher risk for these cancers, while mortality from prostate, stomach, and especially cervical and pediatric cancers was markedly higher in Mexico. Among children, brain cancer and neuroblastoma patterns suggest an environmental role in the etiology of these malignancies as well. Partnered research between the US and Mexico for cancer studies is warranted. © 2017 UICC.

  13. Enquête LMD sur le web

    Directory of Open Access Journals (Sweden)

    Colette Cauvin

    2003-02-01

    Full Text Available En relation avec la mise en place des LMD, une enquête sur le web a été entreprise en janvier 2003 afin de connaître les orientations et les choix des diverses universités délivrant des diplômes de géographie ou d’une discipline similaire. Grâce à R. Schlumberger (laboratoire Image et Ville de nombreux sites ont été consultés et analysés. Qu’elle en soit remerciée.   Cependant, la lecture des informations a été plus malaisée que prévue en raison, en particulier, de la multiplicité des langue...

  14. New Mexico Federal Lands

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This map layer consists of federally owned or administered lands of the United States, Puerto Rico, and the U.S. Virgin Islands. Only areas of 640 acres or more are...

  15. New Mexico Mountain Ranges

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The Geographic Names Information System (GNIS) actively seeks data from and partnerships with Government agencies at all levels and other interested organizations....

  16. Silencing criticism in Mexico

    Directory of Open Access Journals (Sweden)

    Ximena Suárez

    2017-10-01

    Full Text Available Journalists and human rights defenders in Mexico are being attacked in an attempt to silence their criticism. Many are forced to flee or risk being assassinated. The consequences are both personal and of wider social significance.

  17. Mexico - Surface Weather Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Mexican Surface Daily Observations taken at 94 observatories located throughout Mexico, beginning in 1872 and going up through 1981. The data resided on paper...

  18. Acateco de la Frontera Sur (Acateco of the Southern Border).

    Science.gov (United States)

    Maldonado, Roberto Zavala

    This document is one of 17 volumes on indigenous Mexican languages and is the result of a project undertaken by the Archivo de Lenguas Indigenas de Mexico. This volume contains information on Acatec, an indigenous language of Mexico spoken along Mexico's southern border. The objective of collecting such a representative sampling of the linguistic…

  19. Programme de bourse de recherche sur les questions touchant la ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    State and Community Responses to Drug-related Violence in Mexico. Violent conflict related to drug trafficking in Mexico has had a profound impact on the quality of life and health of affected communities. View moreState and Community Responses to Drug-related Violence in Mexico ...

  20. California State Waters Map Series—Offshore of Monterey, California

    Science.gov (United States)

    Johnson, Samuel Y.; Dartnell, Peter; Hartwell, Stephen R.; Cochrane, Guy R.; Golden, Nadine E.; Watt, Janet T.; Davenport, Clifton W.; Kvitek, Rikk G.; Erdey, Mercedes D.; Krigsman, Lisa M.; Sliter, Ray W.; Maier, Katherine L.; Johnson, Samuel Y.; Cochran, Susan A.

    2016-08-18

    IntroductionIn 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath bathymetry data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow subsurface geology.The Offshore of Monterey map area in central California is located on the Pacific Coast, about 120 km south of San Francisco. Incorporated cities in the map area include Seaside, Monterey, Marina, Pacific Grove, Carmel-by-the-Sea, and Sand City. The local economy receives significant resources from tourism, as well as from the Federal Government. Tourist attractions include the Monterey Bay Aquarium, Cannery Row, Fisherman’s Wharf, and the many golf courses near Pebble Beach, and the area serves as a gateway to the spectacular scenery and outdoor activities along the Big Sur coast to the south. Federal facilities include the Army’s Defense Language Institute, the Naval Postgraduate School, and the Fleet Numerical Meteorology and Oceanography Center (operated by the Navy). In 1994, Fort Ord army base, located between Seaside and Marina, was closed; much of former army base land now makes up the Fort Ord National Monument, managed by the U.S. Bureau of Land Management as part of the National Landscape Conservation System. In addition, part of the old Fort Ord is now occupied by California State University, Monterey Bay.The offshore part of the map area lies entirely within the Monterey Bay National