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Sample records for canary islands male

  1. Demographic history of Canary Islands male gene-pool: replacement of native lineages by European

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    Amorim António

    2009-08-01

    Full Text Available Abstract Background The origin and prevalence of the prehispanic settlers of the Canary Islands has attracted great multidisciplinary interest. However, direct ancient DNA genetic studies on indigenous and historical 17th–18th century remains, using mitochondrial DNA as a female marker, have only recently been possible. In the present work, the analysis of Y-chromosome polymorphisms in the same samples, has shed light on the way the European colonization affected male and female Canary Island indigenous genetic pools, from the conquest to present-day times. Results Autochthonous (E-M81 and prominent (E-M78 and J-M267 Berber Y-chromosome lineages were detected in the indigenous remains, confirming a North West African origin for their ancestors which confirms previous mitochondrial DNA results. However, in contrast with their female lineages, which have survived in the present-day population since the conquest with only a moderate decline, the male indigenous lineages have dropped constantly being substituted by European lineages. Male and female sub-Saharan African genetic inputs were also detected in the Canary population, but their frequencies were higher during the 17th–18th centuries than today. Conclusion The European colonization of the Canary Islands introduced a strong sex-biased change in the indigenous population in such a way that indigenous female lineages survived in the extant population in a significantly higher proportion than their male counterparts.

  2. The Limacidae of the Canary Islands

    NARCIS (Netherlands)

    Regteren Altena, van C.O.

    1950-01-01

    CONTENTS Introduction............... 3 Systematic survey of the Limacidae of the central and western Canary Islands 5 Biogeographical notes on the Limacidae of the Canary Islands . . . . 21 Alphabetical list of the persons who collected or observed Limacidae in the Canary Islands.............. 31 Li

  3. The water landscapes of the Canary Islands

    DEFF Research Database (Denmark)

    Lee, Gini; Braae, Ellen Marie; Diedrich, Lisa

    2013-01-01

    Island environments, particularly small archipelagos such as the Canary Islands, are more visible subject to the vagaries of change wrought by ecological and climate dynamics, shifting social conditions and economic impacts subject to global markets, than is witnessed on continental worlds....

  4. The Caridean Crustacea of the Canary Islands

    NARCIS (Netherlands)

    Holthuis, L.B.

    1949-01-01

    The present paper is based mainly on material collected at the Canary Islands during the spring of 1947 by Dr. G. Thorson of Universitetets Zoologiske Museum at Copenhagen and Dr. C. O. van Regteren Altena of the Rijksmuseum van Natuurlijke Historie at Leiden. Most of the specimens were collected by

  5. Stygofauna of the Canary Islands, 9. The amphipod genus Pseudoniphargus (Crustacea) in the Canary Islands

    NARCIS (Netherlands)

    Stock, Jan H.

    1988-01-01

    Pseudoniphargus was known from inland stygohabitats in the Iberian peninsula, the Azores, Madeira, N.W. Africa, and Bermuda, but not from the Canary Islands. Systematic sampling in six of the seven larger islands of the latter archipelago has revealed the presence of the genus in Tenerife (4 species

  6. Natural radiation in Tenerife (Canary Islands)

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Aldecoa, J.C.; Robayna, B.; Allende, A.; Hernandez-Armas, J. (La Laguna Univ., Tenerife (Spain). Dept. de Medicina Fisica y Farmacologia); Poffijn, A. (Ghent Rijksuniversiteit (Belgium). Lab. voor Kernfysica)

    1992-01-01

    Preliminary results of outdoor gamma radioactivity measurements, specific activities of radionuclides in the soil and indoor radon concentrations in Tenerife (Canary Islands) are presented here. The results were obtained using GM MC-71 detectors, HPIC RSS-112, intrinsic Ge detector, charcoal canister and etched track. Outdoor gamma radioactivity levels were determined in each of 103 sites into which the island was divided up. A soil sample was taken at each site to determine concentrations of [sup 226R]a, [sup 232]Th and [sup 40]K. The charcoal canisters were placed for 3 days in dwellings located in the most densely populated areas of the island. In 13 dwellings etched track detectors were also placed for 3 months. The mean gamma radioactivity level was 67 nGy.h[sup -1]. Specific activities of [sup 226]Ra, [sup 232]Th and [sup 40]K were 44 Bq.kg[sup -1], 54 Bq.kg[sup -1] and 665 Bq.kg[sup -1], respectively. The median values for radon concentrations were 58 Bq.m[sup -3] (etched track) and 37 Bq.m[sup -3] (charcoal canisters). A thorough survey of environmental radioactivity in the Canary Islands archipelago is to be undertaken. (author).

  7. Canary Island Date Palm - Orange Co. [ds349

    Data.gov (United States)

    California Department of Resources — This dataset provides the known distribution of Canary Island date palm (Phoenix canariensis) in southern Orange County. The surveys were conducted from May to June,...

  8. Wine, tourism and experience in the Canary Islands' context

    OpenAIRE

    Alonso, Abel Duarte

    2009-01-01

    The Canary Islands or ‘fortunate islands,’ a Spanish archipelago and a well-known mass tourism destination, is experiencing the redevelopment of its wine industry. In this regard, wine tourism appears to be a natural extension emerging from a traditional product - wine - that has been part of Canary Islands’ culture for centuries. This study explores the extent to which wine, tourism and related experiences are becoming integrated in local wineries’ business/marketing concept. Semi-structured...

  9. Biometric variation in Spadella cephaloptera on the Canary Islands (Chaetognatha)

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    Broerse, Alexandra T.C.

    1993-01-01

    Specimens of Spadella cephaloptera from Tenerife, Gran Canaria and Gomera (Canary Islands) were compared biometrically in regards to morphometric and meristic characters. Variation exists among the populations on the islands as well as between the islands. The populations on Gomera seem more distinc

  10. Temporal variability of mass transport across Canary Islands Channels

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    Marrero-Díaz, Ángeles; Rodríguez-Santana, Ángel; José Machín, Francisco; García-Weil, Luis; Sangrà, Pablo; Vélez-Belchí, Pedro; Fraile-Nuez, Eugenio

    2014-05-01

    The equatorward flowing Canary Current (CC) is the main feature of the circulation in the Canary Islands region. The CC flow perturbation by the Canary Islands originate the Canary Eddy Corridor which is the major pathway for long lived eddies in the subtropical North Atlantic (Sangrà et al., 2009, DSR). Therefore the variability of the CC passing through the Canary Archipelago will have both local and regional importance. Past studies on the CC variability trough the Canary Islands point out a clearly seasonal variability (Fraile-Nuez et al, 2010 (JGR); Hernández-Guerra et al, 2002 (DSR)). However those studies where focused on the eastern islands channels missing the variability through the western island channels which are the main source of long lived eddies. In order to fill this gap from November 2012 until September 2013 we conducted trimonthly surveys crossing the whole islands channels using opportunity ships (Naviera Armas Ferries). XBT and XCTD where launched along the cross channels transects. Additionally a closed box circling the Archipelago was performed on October 2013 as part of the cruise RAPROCAN-2013 (IEO) using also XBT and XCTD. Dynamical variables where derived inferring salinity from S(T,p) analytical relationships for the region updated with new XCTD data. High resolution, vertical sections of temperature, potential density, geostrophic velocity and transport where obtained. Our preliminary results suggest that the CC suffer a noticeable acceleration in those islands channels where eddy shedding is more frequent. They also indicate a clearly seasonal variability of the flows passing the islands channels. With this regard we observed significant differences on the obtained seasonal variability with respect the cited past studies on the eastern islands channel (Lanzarote / Fuerteventura - Africa coast). This work was co-funded by Canary Government (TRAMIC project: PROID20100092) and the European Union (FEDER).

  11. Bird pollination of Canary Island endemic plants

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    Ollerton, Jeff; Cranmer, Louise; Stelzer, Ralph J.; Sullivan, Steve; Chittka, Lars

    2009-02-01

    The Canary Islands are home to a guild of endemic, threatened bird-pollinated plants. Previous work has suggested that these plants evolved floral traits as adaptations to pollination by flower specialist sunbirds, but subsequently, they appear to have co-opted generalist passerine birds as sub-optimal pollinators. To test this idea, we carried out a quantitative study of the pollination biology of three of the bird-pollinated plants, Canarina canariensis (Campanulaceae), Isoplexis canariensis (Veronicaceae) and Lotus berthelotii (Fabaceae), on the island of Tenerife. Using colour vision models, we predicted the detectability of flowers to bird and bee pollinators. We measured pollinator visitation rates, nectar standing crops as well as seed-set and pollen removal and deposition. These data showed that the plants are effectively pollinated by non-flower specialist passerine birds that only occasionally visit flowers. The large nectar standing crops and extended flower longevities (>10 days) of Canarina and Isoplexis suggests that they have evolved a bird pollination system that effectively exploits these low frequency non-specialist pollen vectors and is in no way sub-optimal. Seed set in two of the three species was high and was significantly reduced or zero in flowers where pollinator access was restricted. In L. berthelotii, however, no fruit set was observed, probably because the plants were self-incompatible horticultural clones of a single genet. We also show that, while all three species are easily detectable for birds, the orange Canarina and the red Lotus (but less so the yellow-orange Isoplexis) should be difficult to detect for insect pollinators without specialised red receptors, such as bumblebees. Contrary to expectations if we accept that the flowers are primarily adapted to sunbird pollination, the chiffchaff ( Phylloscopus canariensis) was an effective pollinator of these species.

  12. Notes on the Thysanura (Insecta, Apterygota) of the Canary Islands

    NARCIS (Netherlands)

    Wygodzinsky, P.

    1952-01-01

    The present paper constitutes a report on the Machilidae and Lepismatidae collected by Dr. C. O. van Regteren Altena in the Canary Islands in the spring of 1947. We are much obliged to Dr. van Regteren Altena for allowing us to study these interesting specimens. The first notice on Thysanura from th

  13. Canariomyces notabilis, a peculiar Ascomycete from the Canary Islands

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    Arx, von J.A.

    1984-01-01

    The Canary Islands are famous not only for the climate, but also for the flora. Many endemic plants are found, mainly succulents or woody shrubs belonging to the Euphorbiaceae, Fabaceae, Crassulaceae, Boraginaceae and Asteraceae. Monocotyledons are inconspicuous, except for Phoenix canariensis and t

  14. Wine tourism in the Canary Islands: An exploratory study

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    Duarte Alonso, Abel

    2008-04-01

    Full Text Available Wine tourism is experiencing significant development in both new and old European wine regions. In the case of the Canary Islands, wine has been produced and traded for centuries but little is known about the current state or potential for wine tourism on the islands, despite the fact that millions of tourists, including many potential wine tourists, visit the islands each year. In this exploratory study, the perspectives of winery owners and managers on wine tourism are examined via in-depth face-to-face interviews among 23 small winery operators to reveal that the scope for exploiting wine tourism on the islands has been recognized and that some wineries are either already involved in wine tourism, includ-ing as part of a wine trail, or plan to be more involved in the future. It was also discovered, that there were a number of issues that challenge the development of their wine and wine tourism industry, includ-ing competition from non-Canary Island wines and anti-drink-drive laws that are inhibit passers by to consume wine at the cellar door. Operators stressed the need to find a balance between mass tourism and the niche produce of wine. Moreover, the findings identify avenues for future research on wine tourism development in the Canary Islands.

  15. Some additions and corrections to the Coleoptera fauna of the Canary Islands

    OpenAIRE

    2014-01-01

    Two endomychid species described from El Hierro (Canary Islands) are removed from the Canarian fauna: Dapsa hierrensis Franz, 1976 is a synonym of Archipines intricata (Gorham, 1889), nov. syn., and the single specimen (holotype) was probably collected in Central America. Dapsa curta Franz, 1976 is also poorly described and based on a single female. Without a male it is not possible to assess with full confidence if it belongs to the African genus Danae or more probably to the Oriental genus ...

  16. Long term volcanic hazard analysis in the Canary Islands

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    Becerril, L.; Galindo, I.; Laín, L.; Llorente, M.; Mancebo, M. J.

    2009-04-01

    Historic volcanism in Spain is restricted to the Canary Islands, a volcanic archipelago formed by seven volcanic islands. Several historic eruptions have been registered in the last five hundred years. However, and despite the huge amount of citizens and tourist in the archipelago, only a few volcanic hazard studies have been carried out. These studies are mainly focused in the developing of hazard maps in Lanzarote and Tenerife islands, especially for land use planning. The main handicap for these studies in the Canary Islands is the lack of well reported historical eruptions, but also the lack of data such as geochronological, geochemical or structural. In recent years, the use of Geographical Information Systems (GIS) and the improvement in the volcanic processes modelling has provided an important tool for volcanic hazard assessment. Although this sophisticated programs are really useful they need to be fed by a huge amount of data that sometimes, such in the case of the Canary Islands, are not available. For this reason, the Spanish Geological Survey (IGME) is developing a complete geo-referenced database for long term volcanic analysis in the Canary Islands. The Canarian Volcanic Hazard Database (HADA) is based on a GIS helping to organize and manage volcanic information efficiently. HADA includes the following groups of information: (1) 1:25.000 scale geologic maps, (2) 1:25.000 topographic maps, (3) geochronologic data, (4) geochemical data, (5) structural information, (6) climatic data. Data must pass a quality control before they are included in the database. New data are easily integrated in the database. With the HADA database the IGME has started a systematic organization of the existing data. In the near future, the IGME will generate new information to be included in HADA, such as volcanological maps of the islands, structural information, geochronological data and other information to assess long term volcanic hazard analysis. HADA will permit

  17. Health related quality of life of Canary Island citizens

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    Lopez-Bastida Julio

    2010-11-01

    Full Text Available Abstract Background The aim of the study was to describe the health-related quality of life of Canarian population using information from the Canary Island Health Survey and three observational studies developed in the Canary Islands. Methods A descriptive analysis was carried out on a sample of 5.549 Canarian citizens using information from 2004 Canary Island Health Survey and three observational studies on Alzheimer's disease, Stroke and HIV. EQ-5 D was the generic tool used for revealing quality of life of people surveyed. Besides the rate of people reporting moderate or severe decrease in quality of life, TTO-index scores and visual analogue scale were used for assessing health related quality of life of people that suffer a specific diseases and general population. Results Self-perceived health status of citizens that suffer chronic diseases of high prevalence, identifies by the Canary Island Health Survey and other diseases such Alzheimer's disease, Stroke and HIV, independently examined in observational studies, are worse than self-perceived health of general population. Depression/anxiety and pain/discomfort were identified as the dimensions of the EQ-5 D with highest prevalence of problems. Alzheimer's disease and stroke were the illnesses with greater loss of quality of life. Conclusions Health related quality of life should be integrated into a set of information along with expectancy of life, incidence and prevalence of chronic diseases for developing health policy and planning health care activities The combination of information on health related quality of life from population health surveys with data from observational studies enlarges the sources of relevant information for setting health priorities and assessing the impact of health policies.

  18. An offshore wind atlas for the Canary Islands

    Energy Technology Data Exchange (ETDEWEB)

    Martin Mederos, A.C. [Zona Eolica Canaria S.A., Veintinueve de Abril, 30, Las Palmas 35007 (Spain); Medina Padron, J.F. [Departamento de Ingenieria Electrica, Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas (Spain); Feijoo Lorenzo, A.E. [Departamento de Enxeneria Electrica, Universidade de Vigo, ETSEI, Campus de Lagoas-Marcosende, 36310 Vigo (Spain)

    2011-01-15

    In this paper an analysis of the offshore wind potential in the Canary Islands is presented in the shape of a set of wind maps which constitute an offshore wind atlas. It has been drawn up using data processed from 40 weather stations and satellite. Results from satellite mapping, limited area modelling and mesoscalar modelling have been used by applying the technique known as 'one way nesting'. (author)

  19. An Overview of Geodetic Volcano Research in the Canary Islands

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    Fernández, José; González, Pablo J.; Camacho, Antonio G.; Prieto, Juan F.; Brú, Guadalupe

    2015-11-01

    The Canary Islands are mostly characterized by diffuse and scattered volcanism affecting a large area, with only one active stratovolcano, the Teide-Pico Viejo complex (Tenerife). More than 2 million people live and work in the 7,447 km2 of the archipelago, resulting in an average population density three times greater than the rest of Spain. This fact, together with the growth of exposure during the past 40 years, increases volcanic risk with respect previous eruptions, as witnessed during the recent 2011-2012 El Hierro submarine eruption. Therefore, in addition to purely scientific reasons there are economic and population-security reasons for developing and maintaining an efficient volcano monitoring system. In this scenario geodetic monitoring represents an important part of the monitoring system. We describe volcano geodetic monitoring research carried out in the Canary Islands and the results obtained. We consider for each epoch the two main existing constraints: the level of volcanic activity in the archipelago, and the limitations of the techniques available at the time. Theoretical and observational aspects are considered, as well as the implications for operational volcano surveillance. Current challenges of and future perspectives in geodetic volcano monitoring in the Canaries are also presented.

  20. MIO-PLIOCENE CRUSTACEANS FROM THE CANARY ISLANDS, SPAIN

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    JUAN FRANCISCO BETANCORT

    2014-11-01

    Full Text Available There are few previous references to fossil crustaceans for the Neogene marine layers of the Canary Islands (Spain. The Mio-Pliocene marine sedimentary layers in the eastern islands (Gran Canaria, Fuerteventura and Lanzarote were previously characterised by the presence of numerous fossil fauna, mainly anthozoans and molluscs, which correspond to an equatorial-typepalaeoclimate, warmer than the present climate. This Mio-Pliocene transition dated between 9.3 and 4.1 Ma. In this paper, 12 fossil crustacean taxa are identified and classified, including decapods and barnacles: Balanus concavus Bronn, 1831, Balanus spongicola Brown, 1827, Balanus perforatus Bruguière, 1789, Chenolobia testudinaria Linnè, 1767, Tetraclita cf. rubescens Darwin, 1854, Callianassa matsoni Rathbun, 1935, Callianassa sp., Upogebia sp, Eriphia aff. verrucosa (Forskal, 1775 , Maja sp., Scylla michelini Milne-Edwards, 1861 and Ocypode sp. Some of these taxa mean new references for the Atlantic islands and the North African Atlantic and definitely enlarge the palaeographic distribution of Neogene crustaceans beyond the Mediterranean region, extending it to the North Atlantic. Particularly significant are the presence of Tetraclita cf. rubescens ,this being the first reported fossil occurrence of this barnacle outside the North America Pacific coasts, and Chenolobia testudinaria , indicating for the first time the existence of marine turtles in these islands during the Neogene. These results are coherent with previous research hypothesising the existence of a flow of surface water between the Pacific and Atlantic in the Mio-Pliocene transition (Central American Seaway, CAS which explains the arrival of organisms, in larval stage, from Central America to the Canary Islands.

  1. Geochronological constraints on the evolution of El Hierro (Canary Islands)

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    Becerril, Laura; Ubide, Teresa; Sudo, Masafumi; Martí, Joan; Galindo, Inés; Galé, Carlos; Morales, Jose María; Yepes, Jorge; Lago, Marceliano

    2016-01-01

    New age data have been obtained to time constrain the recent Quaternary volcanism of El Hierro (Canary Islands) and to estimate its recurrence rate. We have carried out 40Ar/39Ar geochronology on samples spanning the entire volcanostratigraphic sequence of the island and 14C geochronology on the most recent eruption on the northeast rift of the island: 2280 ± 30 yr BP. We combine the new absolute data with a revision of published ages onshore, some of which were identified through geomorphological criteria (relative data). We present a revised and updated chronology of volcanism for the last 33 ka that we use to estimate the maximum eruptive recurrence of the island. The number of events per year determined is 9.7 × 10-4 for the emerged part of the island, which means that, as a minimum, one eruption has occurred approximately every 1000 years. This highlights the need of more geochronological data to better constrain the eruptive recurrence of El Hierro.

  2. First Report of Vermamoeba vermiformis in the Island of El Hierro, Canary Islands, Spain

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    María Reyes-Batlle

    2016-10-01

    Full Text Available Background: Free-living amoebae (FLA are group of protozoa distributed worldwide in many habitats mainly water and soil related sources. Some members of FLA are able to act as opportunistic pathogens and are environmental carriers of other pathogenic agents such as bacteria and viruses. Vermamoeba vermiformis is a highly abundant FLA species in water bodies and has recently gained environmental importance as it acts as a vehicle of many pathogenic bacteria such as Legionella pneumophila.Cases Report: In this study, water samples were collected from the island of El Hierro, Canary Islands, Spain during 2015. El Hierro island was designated by UNESCO as a biosphere reserve and it is currently the less populated of the Canary Islands. The water samples were culture on 2 % Non-Nutrient Agar (NNA plates covered with a thin layer of heat killed E. coli and checked daily for the presence of FLA. After a week, V. vermiformis amoebae were observed in the plates incubated at room temperature and 37 ºC. Molecular characterization was carried out by amplifying the 18S rDNA gene and DNA sequencing, confirming that the isolated strain belonged to Vermamoeba vermiformis species.Conclusion: To the best of our knowledge, this is the first report of Vermamoeba vermiformis isolation in the island of El Hierro and the second report of this species in the Canary Islands.

  3. Aridity, desalination plants and tourism in the eastern Canary Islands

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    José-León García-Rodríguez

    2016-05-01

    Full Text Available The islands of Lanzarote and Fuerteventura are the easternmost of the Canary Islands, and are located on the southern edge of the temperate zone, in the subtropical anticyclone belt. With less than 150 mm of rainfall a year, they are classified as an arid zone. Their inhabitants have devised original agricultural systems to combat the aridity, although low yields have historically limited socio-economic development and population growth. These systems were used until the introduction of seawater desalination plants and the arrival of tourism in the last third of the twentieth century, which improved living standards for the local population but also led to a cultural transition. Nevertheless, these farming systems have left behind an important regional heritage, with an environmental and scenic value that has played an integral role in the latest phase of development. The systems have become a tourist attraction and have been central to the two islands being designated biosphere reserves by UNESCO. This article aims to analyse the main socioeconomic and land-use changes that have come about as a result of desalination technology.

  4. Two new species of the genus Peristenus Foerster (Hymenoptera: Braconidae: Euphorinae) from the Canary Islands

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    Achterberg, van C.; Guerrero, E.R.

    2003-01-01

    Two new species of the genus Peristenus Foerster (Hymenoptera: Braconidae: Euphorinae) from the Canary Islands are described and illustrated: Peristenus angifemoralis spec. nov. from Tenerife, and P. gloriae spec. nov. from Gran Canaria and Tenerife.

  5. Wind Power adapted to load hollow in the Canary Islands; Adaptacion de Eolicos a huecos de tension en Canarias-2015

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Velazquez, A.

    2008-07-01

    This article is intended to analyse and point out the benefits that could be reached for the Canary Islands electrical systems in relation to wind technology adaptation (actual and future) to the voltage hollow, as required by the Canary Islands Government Directive 1541, dated November 15th 2006. This subject is of vital importance due to the increasing volume of wind power plants foreseen in the Energy Plan for the Canary Islands 2006 (PECAN), who will turn the Canary Islands into a pilot system in relation to wind power integration within an isolated system. (Author)

  6. Additions to the flora of Tenerife (Canary Islands, Spain

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    Verloove, F.

    2011-12-01

    Full Text Available Additions to the flora of Tenerife (Canary Islands, Spain.- Recent fieldwork in Tenerife, especially in September 2010, yielded several interesting new records of non-native vascular plants. Bothriochloa ischaemum var. songarica, “Asian” Cardamine flexuosa, Cestrum parqui, Digitaria violascens, Ficus lyrata, Ficus rubiginosa, Hoffmannseggia glauca, Hyparrhenia rufa subsp. altissima, Jacaranda mimosifolia, Merremia tuberosa, Passiflora morifolia, Phytolacca dioica, Schefflera actinophylla and Solanum abutiloides are reported for the first time from the Canary Islands, while Eragrostis barrelieri var. pygmaea, Ficus microcarpa, Ipomoea purpurea, Leucaena leucocephala subsp. glabrata, Sechium edule, Tradescantia zebrina and Turnera ulmifolia are new to the flora of the island of Tenerife. New records of Acacia cyclops, Atriplex suberecta, Heliotropium curassavicum, Paspalum dilatatum, P. notatum, Pluchea ovalis, Pulicaria paludosa, Sclerophylax spinescens and Solanum villosum subsp. miniatum confirm their recent expansion on the island of Tenerife. New records are provided for the recently described Sporobolus copei . Finally, Paspalum vaginatum (hitherto possibly confused with P. distichum and Potentilla indica are confirmed from the island of Tenerife.

    Adiciones para la flora de Tenerife (Islas Canarias, España.- Algunos recientes trabajos de campo en Tenerife, especialmente en Septiembre de 2010, trajeron consigo varias nuevas e interesantes adiciones de plantas vasculares no autóctonas. Bothriochloa ischaemum var. songarica, Cardamine flexuosa “Asiática”, Cestrum parqui, Digitaria violascens, Ficus lyrata, Ficus rubiginosa, Hoffmannseggia glauca, Hyparrhenia rufa subsp. altissima, Jacaranda mimosifolia, Merremia tuberosa, Passiflora morifolia, Phytolacca dioica, Schefflera actinophylla y

  7. Analysis of hybrid systems for La Graciosa Island (Canary Islands)

    Energy Technology Data Exchange (ETDEWEB)

    Segura, L.; Gomez, A. [Departament of Process Engineering Industrial Enviromental Section, University of Las Palmas de Gran Canaria Campus Universitario of Tafira 35017 Las Palmas de Gran Canaria (Spain); Leon, V. [Red Electrica de Espana, Polygono de la Majuelos 38108 San Cristobal de La Laguna (Spain); Nuez, I. [Departament of Electronic and Automatic Engineering, University of Las Palmas de Gran Canaria Campus Universitario of Tafira 35017 Las Palmas de Gran Canaria (Spain)

    2006-07-01

    The main objectives of the study are the integration of the renewable energies, the study of the production of the hydrogen and the utilization in areas where have a high potential of renewable origin sources and a low capacity of drinkable water and energy power. In this work, it has been done the study of the actual energy necessity of the island and it is posed a series of solutions to its energy system. It is analyzed three cases. In the first step, it is exposed an isolated system with renewable energies and hydrogen as energy storage; in the second step, it is studied a system with renewable energies, hydrogen and an electricity-generating group as support; and in the third step, it is analyzed a case with renewable energy and connexion to the network (in this case, it would already not be an isolated system). (authors)

  8. Pre-Hispanic Sanctuaries in the Canary Islands

    Science.gov (United States)

    Belmonte, Juan Antonio

    Cultural astronomy studies in the Canarian archipelago now have a tradition spanning two decades. The statistical relevance of astronomical implications for a certain number of sites and the spectacular character of some of the astronomical hierophanies discovered - with low probability of having been produced by chance in most cases - clearly points to an intentionality in the astronomical relationships discovered so far. All these arguments strongly suggest that tracking the movement of the celestial bodies was an important consideration in the erection and purpose of many pre-Hispanic sanctuaries. The alignment of footprint engravings at Montaña Tindaya, and the major lunistice moonrise at Roque Nublo and the summer solstice sunset at Teide, as observed from the sacred sites of Bentaiga and Gamona, respectively, may also be catalogued as outstanding examples of the strong relationship between astronomy and landscape in ancient Canary Islands culture. The recently discovered light-and-shadow effects at Risco Caído will also be briefly discussed.

  9. Phytoseiid mites of the Canary Islands (Acari, Phytoseiidae. II. Tenerife and La Gomera Islands

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    Ferragut, F.

    2007-12-01

    Full Text Available Phytoseiid mites (Acari, Phytoseiidae inhabiting plants in natural ecosystems from Tenerife and La Gomera islands (Canary Islands have been studied. Surveys were conducted from 1997 to 2002. Eleven species were collected, one of them being reported for the first time from the Canary Islands and six of them reported for the first time from Tenerife and La Gomera islands. Euseius machadoi n. sp. collected from woody plants in the Canarian laurisilva is proposed as a new species.

    En muestreos realizados desde 1997 hasta 2002 se ha estudiado la fauna de ácaros fitoseidos (Acari, Phytoseiidae asociada a plantas de ecosistemas naturales de las islas de Tenerife y La Gomera (Islas Canarias. Se han recolectado un total de 11 especies, siendo una de ellas citada por vez primera en las islas Canarias y seis de ellas citadas por primera vez en las islas de Tenerife y La Gomera. Euseius machadoi n. sp., recolectado en plantas leñosas de la laurisilva canaria, se propone como una nueva especie.

  10. Vicia vulcanorum (Fabaceae a new species from the island of Lanzarote (Canary Islands

    Directory of Open Access Journals (Sweden)

    Morales-Mateos, J. B.

    2012-12-01

    Full Text Available Vicia vulcanorum J. Gil & M. L. Gil (Fabaceae, a new species of subg. Cracca (Dumort. Peterm., sect. Cracca Dumort. is described and illustrated from the island of Lanzarote, Canary Islands, north-west of Africa. It is related to and compared with Vicia cirrhosa C. Sm. ex Webb & Berthel. and Vicia filicaulis Webb & Berthel., two endemic species from the western and central group of the Canary Islands, and Vicia ferreirensis Goyder, an endemic species from Porto Santo Island, Madeira Archipelago.Se describe e ilustra Vicia vulcanorum J. Gil & M. L. Gil (Fabaceae, una nueva especie y endemismo de la isla de Lanzarote, Islas Canarias, perteneciente al subg. Cracca (Dumort. Peterm., sect. Cracca Dumort. Se encuentra relacionada y es comparada con Vicia cirrhosa C. Sm. ex Webb & Berthel. y Vicia filicaulis Webb & Berthel., especies endémicas de las islas centrales y occidentales del archipiélago canario, y con Vicia ferreirensis Goyder, especie endémica de la isla de Porto Santo, en el archipiélago de Madeira.

  11. Boring sponges (Porifera, Clionidae) collected during the "Tydeman" Canary Islands expedition Cancap-II, 1977

    NARCIS (Netherlands)

    Groot, de R.A.

    1980-01-01

    INTRODUCTION AND MATERIAL The boring sponges of the Canary Islands have never been studied in any detail, but the boring fauna of this archipelago cannot be expected to be very rich. All islands are volcanic and calcareous rocks are not common. Consequently, in most areas large shells and rhodophyte

  12. A high-resolution numerical study at the Canary Islands off Northwest Africa

    Science.gov (United States)

    Mason, Evan; Colas, Francois; Molemaker, Jeroen; Sangrà, Pablo; Pascual, Ananda; McWilliams, James

    2015-04-01

    The Canary Island archipelago lies partially within the upwelling region off the northwest coast of Africa where it perturbs the southwestward flowing Canary Current. The circulation around the islands is complex, as has been revealed in studies based on satellite imagery and from in situ data. Cyclonic and anticyclonic eddies are shed by the islands. Filaments of cold upwelling water extend from the African coast and interact with the island eddies. However, our understanding of these mesoscale features and their interactions is still limited by the sparsity of data available. Few modelling studies have been done for the Canary Island region, and none has yet specifically addressed the dynamics of the island and coastal circulation. A high-resolution regional ocean model (ROMS) configuration has been developed to study the dynamics in this region. We take an offline-nesting approach: A large domain that covers the Canary Basin at 7.5-km resolution feeds two successively finer domains of 3 and 1 km. The 1 km grid is focused on the Canary Islands and nearby African coast. The surface and boundary forcings are climatological. Results at the basin scale have shown a good agreement with the observed regional seasonal cycle. Here, we present preliminary results from the nested solutions where eddies, fronts and filaments are found in abundance. Model eddy conversion terms confirm the observed seasonal cycle of eddy generation, and point to both baroclinic and barotropic processes as sources of instability. Submesocale activity exhibits a pronounced seasonal cycle which is consistent with previous studies in other regions. Time series of drag and lift forces at the island of Gran Canaria are discussed that show the high variability of the incident Canary Current and the associated eddy generation process.

  13. Colonization and diversification of the Euphorbia species (sect. Aphyllis subsect. Macaronesicae) on the Canary Islands

    Science.gov (United States)

    Sun, Ye; Li, Yanshu; Vargas-Mendoza, Carlos Fabián; Wang, Faguo; Xing, Fuwu

    2016-01-01

    Diversification between islands and ecological radiation within islands are postulated to have occurred in the Euphorbia species (sect. Aphyllis subsect. Macaronesicae) on the Canary Islands. In this study, the biogeographical pattern of 11 species of subsect. Macaronesicae and the genetic differentiation among five species were investigated to distinguish the potential mode and mechanism of diversification and speciation. The biogeographical patterns and genetic structure were examined using statistical dispersal-vicariance analysis, Bayesian phylogenetic analysis, reduced median-joining haplotype network analysis, and discriminant analysis of principal components. The gene flow between related species was evaluated with an isolation-with-migration model. The ancestral range of the species of subsect. Macaronesicae was inferred to be Tenerife and the Cape Verde Islands, and Tenerife-La Gomera acted as sources of diversity to other islands of the Canary Islands. Inter-island colonization of E. lamarckii among the western islands and a colonization of E. regis-jubae from Gran Canaria to northern Africa were revealed. Both diversification between islands and radiation within islands have been revealed in the Euphorbia species (sect. Aphyllis subsect. Macaronesicae) of the Canary Islands. It was clear that this group began the speciation process in Tenerife-La Gomera, and this process occurred with gene flow between some related species. PMID:27681300

  14. Polypharmacy in psychiatric practice in the Canary Islands

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    Sanz Emilio J

    2004-07-01

    Full Text Available Abstract Background Polypharmacy with psychoactive drugs is an increasingly common and debatable contemporary practice in clinical psychiatry based more upon experience than evidence. The objective of this study was to evaluate the prevalence and conditioners of polypharmacy in psychiatric patients. Method A cross-sectional survey was carried out using the Canary Islands Health Service Clinical Records Database. A representative sample (n = 2,647 of patients with mental disorders receiving psychotropic medication was studied. Results The mean number of psychoactive drugs prescribed was 1.63 ± 0.93 (range 1–7. The rate of polypharmacy was 41.9%, with 27.8% of patients receiving two drugs, 9.1% receiving three, 3.2% receiving four, and 1.8% of the patients receiving five or more psychotropic drugs. Multiple regression analysis shows that variables sex and diagnosis have a predictive value with regard to the number of psychotropic drug used, being men and schizophrenic patients the most predisposed. Benzodiazepines were the more prevalent drugs in monotherapy, while anticonvulsants and antipsychotics were the more used in combination with other treatment. A questionable very high degree of same-class polypharmacy was evidenced, while multi-class, adjunctive and augmentation polypharmacy seem to be more appropriate. Conclusions Almost half of the psychiatric patients are treated with several psychotropics. Polypharmacy is common and seems to be problematic, especially when same class of drugs are prescribed together. Some diagnoses, such as schizophrenia, are associated with an increase risk of Polypharmacy but there is a lack of evidence based indicators that allows for quality evaluation on this practice.

  15. Portuguese migration to the Canary Islands: an analysis based on surnames.

    Science.gov (United States)

    Román-Busto, J; Fuster, V; Colantonio, S E

    2012-01-01

    As a part of a wider analysis of population and genetic exchange between Spain and Portugal, the long-term pattern of Portuguese immigration to the Canary Islands was studied by means of the frequency of Portuguese surnames. A database of 1,995,833 individuals was obtained from the Spanish National Statistics Institute (2006). Among the 826 most frequent surnames to appear, 79 surnames of Portuguese origin were selected. The distribution of these surnames by municipalities and islands, the Fisher index of diversity, and the Lasker inter-population relationship coefficients R(ij) were considered. These coefficients were inter-correlated and correlated with other variables that could have influenced the distribution of surnames. From the observed distribution of the frequency of surnames, a non-random migration pattern conditioned by economic factors was found. The greatest diversity of surnames existed in cane cultivating areas after the first arrival of Portuguese immigrants. A later dispersion of surnames among islands was correlated with the inter-island geographic distances. In some islands the arrival of new immigrants continued due to their strategic location within the Canary archipelago. The Canary Islands reveal a high frequency and diversity of Portuguese surnames. The results also prove a heterogeneous distribution of these surnames throughout the archipelago. In contrast to the Portuguese archipelagos, some Canary localities have received immigrants continuously because of their economic importance in sugar cane cultivation and strategic geographic location on the maritime routes to Africa and America.

  16. Imaging Canary Island hotspot material beneath the lithosphere of Morocco and southern Spain

    Science.gov (United States)

    Miller, Meghan S.; O'Driscoll, Leland J.; Butcher, Amber J.; Thomas, Christine

    2015-12-01

    The westernmost Mediterranean has developed into its present day tectonic configuration as a result of complex interactions between late stage subduction of the Neo-Tethys Ocean, continental collision of Africa and Eurasia, and the Canary Island mantle plume. This study utilizes S receiver functions (SRFs) from over 360 broadband seismic stations to seismically image the lithosphere and uppermost mantle from southern Spain through Morocco and the Canary Islands. The lithospheric thickness ranges from ∼65 km beneath the Atlas Mountains and the active volcanic islands to over ∼210 km beneath the cratonic lithosphere in southern Morocco. The common conversion point (CCP) volume of the SRFs indicates that thinned lithosphere extends from beneath the Canary Islands offshore southwestern Morocco, to beneath the continental lithosphere of the Atlas Mountains, and then thickens abruptly at the West African craton. Beneath thin lithosphere between the Canary hot spot and southern Spain, including below the Atlas Mountains and the Alboran Sea, there are distinct pockets of low velocity material, as inferred from high amplitude positive, sub-lithospheric conversions in the SRFs. These regions of low seismic velocity at the base of the lithosphere extend beneath the areas of Pliocene-Quaternary magmatism, which has been linked to a Canary hotspot source via geochemical signatures. However, we find that this volume of low velocity material is discontinuous along strike and occurs only in areas of recent volcanism and where asthenospheric mantle flow is identified with shear wave splitting analyses. We propose that the low velocity structure beneath the lithosphere is material flowing sub-horizontally northeastwards beneath Morocco from the tilted Canary Island plume, and the small, localized volcanoes are the result of small-scale upwellings from this material.

  17. New data on the Tanaidacea (Crustacea: Peracarida) from the Canary Islands, with a description of a new species of Apseudopsis.

    Science.gov (United States)

    Esquete, Patricia; Ramos, Eva; Riera, Rodrigo

    2016-03-21

    Benthic samples from two harbours at El Hierro and Tenerife (Canary Islands) yielded three species of Tanaidacea. Tanais dulongii and Leptochelia savignyi are recorded for the first time in Tenerife and El Hierro, respectively. A new species of Apseudomorpha, Apseudopsis rogi, was collected in both harbours and can be differentiated from other species of the genus by the male having a cheliped merus with a distinctive, cylindrical dorso-proximal spur. This is the first species of Apseudopsis described for the Macaronesian region. A key to the Atlantic and Mediterranean species of Apseudopsis is provided.

  18. Origin of three-armed rifts in volcanic islands: the case of El Hierro (Canary Islands)

    Science.gov (United States)

    Galindo Jiménez, Inés; Becerril Carretero, Laura; Martí Molist, Joan; Gudmundsson, Agust

    2015-04-01

    Rifts zones in volcanic oceanic islands are common structures that have been explained through several theories/models. However, despite all these models it is as yet unclear whether it is the intense intrusive activity or the sector collapses that actually control the structural evolution and geometry of oceanic-island rift zones. Here we provide a new hypothesis to explain the origin and characteristics of the feeding system of oceanic-island rift zones based on the analysis of more than 1700 surface, subsurface (water galleries), and submarine structural data from El Hierro (Canary Islands). El Hierro's geological structure is primarily controlled by a three-armed rift-zone, the arms striking NE, WSW and S. Between the rift axes there are three valleys formed during huge landslides: El Golfo, El Julan, and Las Playas. Our results show: (1) a predominant NE-SW strike of structural elements, which coincides with the main regional trend of the Canary Archipelago as a whole; (2) a clear radial strike distribution of structural elements for the whole volcanic edifice (including submarine flanks) with respect to the centre of the island; (3) that the rift zones are mainly subaerial structures and do not propagate through the submarine edifice; (4) that it is only in the NE rift that structures have a general strike similar to that of the rift as a whole, and; (5) that in the W and S rifts there is not clear main direction, showing the structural elements in the W rift a fan distribution coinciding with the general radial pattern in the island as a whole. Based on these data, we suggest that the radial-striking structures reflect comparatively uniform stress fields that operated during the constructive episodes, mainly conditioned by the combination of overburden pressure, gravitational spreading, and magma-induced stresses. By contrast, in the shallower parts of the edifice, that is, the NE-SW, N-S and WNW-ESE-striking structures, reflect local stress fields related

  19. A new species of Sarcodictyon (Anthozoa: Stolonifera) from Tenerife, Canary Islands

    NARCIS (Netherlands)

    Ocaña, O.; Brito, A.; Nuñez, J.

    1992-01-01

    A new species of Stolonifera, Sarcodictyon canariensis, from Tenerife, Canary Islands, is described and illustrated. It is characterized by its large size, the form of its sclerites and internal anatomy. The material was collected at a depth of 95-130 m in the community of Dendrophyllia ramea (Linna

  20. [European expansion and aboriginal demographics. The example of the Canary Islands, 1400-1505].

    Science.gov (United States)

    Macias Hernandez, A M

    1992-01-01

    The author examines the indigenous population of the Canary Islands from the thirteenth century to 1505. He uses the limited available data to describe the effect of contact with and eventual colonization by Spain on such aspects as spatial distribution, mortality, and forced labor migration to the Continent. Comparisons are made with the indigenous experience in the Americas.

  1. The genus Alvania on the Canary islands and Madeira (Mollusca: Gastropoda), part 2 [final part

    NARCIS (Netherlands)

    Moolenbeek, R.G.; Hoenselaar, H.J.

    1998-01-01

    Five Alvania species from the Canary Islands and the Madeira Archipelago are revised. A new species to science, A. johannae is described and for three species lectotypes are designated. Altogether 13 littoral alvaniids are presently known from this area. Doubtful records are enumerated and a list of

  2. Teachers' Opinions of Student Dropout from Formal Music Education Centres of the Canary Islands

    Science.gov (United States)

    Lorenzo Socorro, Sonia; Escandell Bermúdez, María Olga; Castro Sánchez, José Juan

    2016-01-01

    One hundred and eighty-five teachers were surveyed to determine their opinion of student dropout from formal music centres in the Canary Islands. The goal of the study was to investigate the causes of dropout and strategies to prevent it. Teachers' opinions were collected by means of a questionnaire. The influence of the environment on the…

  3. Stygofauna of the Canary Islands, 8 Amphipoda (Crustacea) from inland groundwaters of Fuerteventura

    NARCIS (Netherlands)

    Stock, Jan H.

    1988-01-01

    New material of Bogidiella from Fuenteventura (Canary Islands) provided evidence that the specimens of the genus previously recorded from inland groundwaters belong to a species new to science: B. (Stygogidiella) purpuriae, closely related to the thalassostygobiont, B. (S.) uniramosa from Lanzarote.

  4. Stygofauna of the Canary Islands, 13 Die Polychaeten der Sammelreisen 1985 und 1987

    NARCIS (Netherlands)

    Hartmann-Schröder, Gesa

    1988-01-01

    Fifteen species of Polychaeta have been studied, two of which not identifyable to species level. Ten species are recorded from the Canary Islands for the first time. The majority of the species is distributed more or less widely in the warmer parts of the oceans, 2 are cosmopolitan. Namanereis humme

  5. Spatial vent opening probability map of El Hierro Island (Canary Islands, Spain)

    Science.gov (United States)

    Becerril, Laura; Cappello, Annalisa; Galindo, Inés; Neri, Marco; Del Negro, Ciro

    2013-04-01

    The assessment of the probable spatial distribution of new eruptions is useful to manage and reduce the volcanic risk. It can be achieved in different ways, but it becomes especially hard when dealing with volcanic areas less studied, poorly monitored and characterized by a low frequent activity, as El Hierro. Even though it is the youngest of the Canary Islands, before the 2011 eruption in the "Las Calmas Sea", El Hierro had been the least studied volcanic Island of the Canaries, with more historically devoted attention to La Palma, Tenerife and Lanzarote. We propose a probabilistic method to build the susceptibility map of El Hierro, i.e. the spatial distribution of vent opening for future eruptions, based on the mathematical analysis of the volcano-structural data collected mostly on the Island and, secondly, on the submerged part of the volcano, up to a distance of ~10-20 km from the coast. The volcano-structural data were collected through new fieldwork measurements, bathymetric information, and analysis of geological maps, orthophotos and aerial photographs. They have been divided in different datasets and converted into separate and weighted probability density functions, which were then included in a non-homogeneous Poisson process to produce the volcanic susceptibility map. Future eruptive events on El Hierro is mainly concentrated on the rifts zones, extending also beyond the shoreline. The major probabilities to host new eruptions are located on the distal parts of the South and West rifts, with the highest probability reached in the south-western area of the West rift. High probabilities are also observed in the Northeast and South rifts, and the submarine parts of the rifts. This map represents the first effort to deal with the volcanic hazard at El Hierro and can be a support tool for decision makers in land planning, emergency plans and civil defence actions.

  6. Nannofossils in 2011 El Hierro eruptive products reinstate plume model for Canary Islands

    Science.gov (United States)

    Zaczek, Kirsten; Troll, Valentin R.; Cachao, Mario; Ferreira, Jorge; Deegan, Frances M.; Carracedo, Juan Carlos; Soler, Vicente; Meade, Fiona C.; Burchardt, Steffi

    2015-01-01

    The origin and life cycle of ocean islands have been debated since the early days of Geology. In the case of the Canary archipelago, its proximity to the Atlas orogen led to initial fracture-controlled models for island genesis, while later workers cited a Miocene-Quaternary east-west age-progression to support an underlying mantle-plume. The recent discovery of submarine Cretaceous volcanic rocks near the westernmost island of El Hierro now questions this systematic age-progression within the archipelago. If a mantle-plume is indeed responsible for the Canaries, the onshore volcanic age-progression should be complemented by progressively younger pre-island sedimentary strata towards the west, however, direct age constraints for the westernmost pre-island sediments are lacking. Here we report on new age data obtained from calcareous nannofossils in sedimentary xenoliths erupted during the 2011 El Hierro events, which date the sub-island sedimentary rocks to between late Cretaceous and Pliocene in age. This age-range includes substantially younger pre-volcanic sedimentary rocks than the Jurassic to Miocene strata known from the older eastern islands and now reinstate the mantle-plume hypothesis as the most plausible explanation for Canary volcanism. The recently discovered Cretaceous submarine volcanic rocks in the region are, in turn, part of an older, fracture-related tectonic episode.

  7. Contrasting biogeography of endemic and alien terrestrial species in the Canary Islands

    OpenAIRE

    Vilà, Montserrat

    2006-01-01

    Endemics and alien organisms can be considered two faces of the same coin, since management of both groups of taxa have strongly interrelated conservation implications. Islands are rich in endemic species and are also very vulnerable to biological invasions. We analysed the biogeography and taxonomy of endemic and alien terrestrial species in the Canary Islands including fungi, lichens, bryophytes, vascular plants, arthropods, molluscs, annelids and vertebrates. By using the plant dataset we ...

  8. Geochemical and mineralogical evidence for Sahara and Sahel dust additions to Quaternary soils on Lanzarote, eastern Canary Islands, Spain

    Science.gov (United States)

    Muhs, D.R.; Budahn, J.; Skipp, G.; Prospero, J.M.; Patterson, D.; Bettis, E. Arthur

    2010-01-01

    Africa is the most important source of dust in the world today, and dust storms are frequent on the nearby Canary Islands. Previous workers have inferred that the Sahara is the most important source of dust to Canary Islands soils, with little contribution from the Sahel region. Soils overlying a late Quaternary basalt flow on Lanzarote, Canary Islands, contain, in addition to volcanic minerals, quartz and mica, exotic to the island's bedrock. Kaolinite in the soils also likely has an exotic origin. Trace-element geochemistry shows that the soils are derived from varying proportions of locally derived basalt and African dust. Major-element geochemistry, clay mineralogy and interpretation of satellite imagery suggest that dust additions to the Canary Islands come not only from the Sahara Desert, but also from the Sahel region. ?? Published 2010. This article is a US Government work and is in the public domain in the USA.

  9. Finding of Parastrongylus cantonensis (Chen, 1935) in Rattus rattus in Tenerife, Canary Islands (Spain).

    Science.gov (United States)

    Foronda, Pilar; López-González, Mercedes; Miquel, Jordi; Torres, Jordi; Segovia, Matías; Abreu-Acosta, Néstor; Casanova, Juan Carlos; Valladares, Basilio; Mas-Coma, Santiago; Bargues, María Dolores; Feliu, Carlos

    2010-05-01

    Parastrongylus cantonensis is a parasite of murid rodents that can infect humans and cause health problems as eosinophilic meningitis. Although it is endemic in south Asia, the Pacific islands, Australia, USA, and a few Caribbean islands, it has been extended to new geographical regions. In the Canary Islands (Spain) a survey of helminths of Rattus rattus, Rattus norvegicus and Mus musculus domesticus was carried out. Furthermore, five species of molluscs were examined for nematode larvae to determine whether they are potential intermediate hosts of P. cantonensis. Nematodes were found in the lungs of 15% of 67 R. rattus examined in Tenerife, one of the four studied islands, with a prevalence of 20% in the highest focus of infection. Based on morphological and molecular analysis, with the complete internal transcribed spacer 2 (ITS-2) and a fragment of the small subunit ribosomal RNA (SSU rRNA) nucleotide sequences, nematodes were identified as P. cantonensis. Larval nematodes found from snails and slugs were identified as third-stage (L(3)) Metastrongyloidea, but the molecular study showed that they did not belong to P. cantonensis. This is the first finding of angiostrongyliasis in rats in the Canary Islands (Spain). New molecular data for this species and Parastrongylus dujardini are reported. The presence of P. cantonensis in Tenerife could be of importance from the public health point of view. Further studies are required in order to look for other potential foci of infections in the Canary Islands.

  10. Xenopsylla spp. (Siphonaptera: Pulicidae in murid rodents from the Canary Islands: An update

    Directory of Open Access Journals (Sweden)

    Sánchez S.

    2012-11-01

    Full Text Available The geographical and host distributions of Xenopsylla fleas parasitizing murid rodents on the Canary Islands have been reported. Three Xenopsylla species, X. cheopis, X. brasiliensis and X. guancha, have been detected on two rodents species, Mus musculus and Rattus rattus. X. guancha has been the most prevalent species detected, specifically on M. musculus, the most abundant rodent, but it has been detected only on three eastern islands, where the species is endemic. X. cheopis has been shown to be the most widely distributed species throughout the archipelago and the species most frequently found on R. rattus. X. brasiliensis has been shown to be the least prevalent Xenopsylla species, with the lowest geographical distribution on the Canary Islands and focused only on R. rattus. The detection of both X. cheopis and X. brasiliensis on the island of Lanzarote, and of X. guancha on the island of Fuerteventura and the islet of La Graciosa represents the first report of these species on those particular Canary Islands.

  11. Spatial probability distribution of future volcanic eruptions at El Hierro Island (Canary Islands, Spain)

    Science.gov (United States)

    Becerril, Laura; Cappello, Annalisa; Galindo, Inés; Neri, Marco; Del Negro, Ciro

    2013-05-01

    The 2011 submarine eruption that took place in the proximity of El Hierro Island (Canary Islands, Spain) has raised the need to identify the most likely future emission zones even on volcanoes characterized by low frequency activity. Here, we propose a probabilistic method to build the susceptibility map of El Hierro, i.e. the spatial distribution of vent opening for future eruptions, based on the probabilistic analysis of volcano-structural data of the Island collected through new fieldwork measurements, bathymetric information, as well as analysis of geological maps, orthophotos and aerial photographs. These data have been divided into different datasets and converted into separate and weighted probability density functions, which were included in a non-homogeneous Poisson process to produce the volcanic susceptibility map. The most likely area to host new eruptions in El Hierro is in the south-western part of the West rift. High probability locations are also found in the Northeast and South rifts, and along the submarine parts of the rifts. This map represents the first effort to deal with the volcanic hazard at El Hierro and can be a support tool for decision makers in land planning, emergency measures and civil defense actions.

  12. Confirmation of the presence of Ischnura senegalensis (Rambur, 1842 on the Canary Islands

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    Sánchez–Guillén R. A.

    2015-05-01

    Full Text Available The presence of one or two species of damselflies of the genus Ischnura in the Canary Islands has been a matter of debate in the recent years. The first published records listed I. senegalensis as the only zygopteran inhabiting the archipelago, but this proved to be wrong, and until recently, all specimens of Ischnura captured in the islands were unanimously regarded as belonging to I. saharensis. Recent photographic evidence, however, is compatible with the presence of I. senegalensis. In this study, we give morphological and genetic evidence of the presence of I. senegalensis in the Canary Islands, and we discuss the importance of voucher specimens to correctly identify very similar species.

  13. Genetically depauperate in the continent but rich in oceanic islands: Cistus monspeliensis (Cistaceae in the Canary Islands.

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    Mario Fernández-Mazuecos

    Full Text Available BACKGROUND: Population genetic theory holds that oceanic island populations are expected to have lower levels of genetic variation than their mainland counterparts, due to founder effect after island colonization from the continent. Cistus monspeliensis (Cistaceae is distributed in both the Canary Islands and the Mediterranean region. Numerous phylogenetic results obtained in the last years allow performing further phylogeographic analyses in Cistus. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed sequences from multiple plastid DNA regions in 47 populations of Cistus monspeliensis from the Canary Islands (21 populations and the Mediterranean basin (26 populations. The time-calibrated phylogeny and phylogeographic analyses yielded the following results: (1 a single, ancestral haplotype is distributed across the Mediterranean, whereas 10 haplotypes in the Canary Islands; (2 four haplotype lineages are present in the Canarian Islands; (3 multiple colonization events across the archipelago are inferred; (4 the earliest split of intraspecific lineages occurred in the Early to Middle Pleistocene (<930,000 years BP. CONCLUSIONS/SIGNIFICANCE: The contrasting pattern of cpDNA variation is best explained by genetic bottlenecks in the Mediterranean during Quaternary glaciations, while the Canarian archipelago acted as a refugium of high levels of genetic diversity. Active colonization across the Canarian islands is supported not only by the distribution of C. monspeliensis in five of the seven islands, but also by our phylogeographic reconstruction in which unrelated haplotypes are present on the same island. Widespread distribution of thermophilous habitats on every island, as those found throughout the Mediterranean, has likely been responsible for the successful colonization of C. monspeliensis, despite the absence of a long-distance dispersal mechanism. This is the first example of a plant species with higher genetic variation among oceanic island

  14. Canary Islands (Spain): Their Importance in NATO’s Strategy.

    Science.gov (United States)

    1987-04-22

    the fact that they are now members of the same western organizations such as NATO 13 facttha the ar no memersof te sme esten oganiatins uch s NT’ and...and possibly from Libya; but it is confronted by a major Moroccan military presence. The conflict in the Western Sahara will probably endure because...but now is worse because of the Moroccan King’s speech claiming sovereignty over the Spanish cities of Ceuta and Melila. The Canaries feel that in the

  15. Ecophysiology of the invader Pennisetum setaceum and three native grasses in the Canary Islands

    Science.gov (United States)

    González-Rodríguez, Agueda M. a.; Baruch, Zdravko; Palomo, Debora; Cruz-Trujillo, Gilberto; Jiménez, M. a. Soledad; Morales, Domingo

    2010-03-01

    Pennisetum setaceum (fountain grass) is an aggressive invader in the arid and semi-arid habitats of the tropics and subtropics. In the last twenty years the spread of fountain grass in the Canary Islands has been very rapid. We compared its ecophysiological, architectural and reproductive traits with those of three native grasses ( Hyparrhenia hirta, Cenchrus ciliaris and Aristida adscensionis) in two habitats of Tenerife Island which differ in rainfall. The detection of traits that differ between native and invader grasses may provide information for the improved control and eradication of the latter contributing to protect the native plant diversity. P. setaceum and the native grasses differed in all measured traits and in their response to water availability which is more restricted in the southern site. Specific leaf area was lower in P. setaceum than in the native grasses. Although this reduces carbon assimilation per unit area, it also reduces transpiration, increasing water use efficiency and contributes to the maintenance of high relative water content. Leaf N in P. setaceum was lower than in the native grasses indicating higher nitrogen use efficiency. The activity of photosystem II was higher and lasted longer in P. setaceum than in the native grasses. The ecophysiological traits of P. setaceum support its large size, extensive canopy and shorter leaf senescence period. They confer considerable competitive advantage to the invader and partially explain its success in the Canary Islands. The differences between the invader and the native grasses were maintained in both sites revealing a good adaptation of P. setaceum to the low resource local habitats in the Canary Islands and confirms its large plasticity. The large invasive potential of P. setaceum, in concert with the projected global changes, forecast eventual risks for the conservation of the endemic flora and remaining native communities in the Canary Islands.

  16. Fluvial dissection, isostatic uplift, and geomorphological evolution of volcanic islands (Gran Canaria, Canary Islands, Spain)

    Science.gov (United States)

    Menéndez, Inmaculada; Silva, Pablo G.; Martín-Betancor, Moises; Pérez-Torrado, Francisco José; Guillou, Hervé; Scaillet, S.

    2008-11-01

    Digital analysis of torrential gullies ('barrancos') deeply incised into the volcanic Island of Gran Canaria (Canary Islands) allows us to extract the longitudinal profiles and pre-incision surfaces for individual basins, from which morphometric parameters (length, elevation, area, slope) have been calculated. Other derived parameters, such as ridgeline profiles, maximum incision values, volume removed by fluvial erosion, geophysical relief and isostatic uplift, have also been computed. Based on K/Ar ages for the island, well-constrained incision-uplift rates have been calculated by means of the combination of different methodological approaches commonly used in orogens and large mountain ranges. The geomorphological and morphometric analyses reveal that the island is clearly divided into four environmental quadrants determined by the combination of a couple of key-factors: the age of the volcanic surfaces and the climatic conditions. These factors determine a young sector covered with Plio-Quaternary platform-forming lavas (finished at 1.9-1.5 Ma) evolving under contrasting wet (NE) to dry (SE) climates, and an older sector, conserving the residual surfaces of the Miocene shield building (14.5-8.7 Ma) at the ridgelines, also subjected to wet (NW) and dry (SW) climates. Incision is related to the age zonation of the island. Maximum incisions (< 1200 m) are logically recorded in the older SW sector of the island, but incision rates are directly related to the climatic zonation, with maximum mean values in the wet Northern quadrants (0.18-0.12 mm/yr). The evaluation of the material removed by fluvial erosion for individual basins allows us to assess the consequent theoretical isostatic response in the different sectors of the island. The obtained uplift rates indicate that water availability (by drainage area and elevation) is a relevant controlling factor: the records from the wet Northern sectors show uplift values of between 0.09 and 0.03 mm/yr, whereas in the

  17. First larval record of Mesocestoides in carnivora of Tenerife (Canary Islands).

    Science.gov (United States)

    Foronda, Pilar; Pérez Rivero, Alfredo; Santana Morales, María A; Kabdur, Alicia; González, Ana C; Quispe Ricalde, M Antonieta; Feliu, Carlos; Valladares, Basilio

    2007-02-01

    Larvae of Mesocestoides sp. were recovered in Tenerife (Canary Islands) in 2004 from the peritoneal cavities of 2 domestic dogs and a domestic cat. Morphological and molecular identification were carried out. Mesocestoides litteratus from Vulpes vulpes was sequenced for the first time using the ITS-2 region (18S rDNA), and was included in the phylogenetic analysis to compare the sequence variability among these and other Mesocestoides spp. belonging to different carnivores. Phylogenetic studies were carried out based on maximum parsimony and neighbor-joining analysis. The results showed the relationships between these and other previously published Mesocestoides species. Moreover, it is demonstrated that Mesocestoides sp. from Tenerife comprises a previously unreported sequence. This is the first larval record of Mesocestoides sp. in domestic animals from Tenerife, Canary Islands, Spain.

  18. Mitochondrial DNA diversity in 17th-18th century remains from Tenerife (Canary Islands).

    Science.gov (United States)

    Maca-Meyer, Nicole; Cabrera, Vicente M; Arnay, Matilde; Flores, Carlos; Fregel, Rosa; González, Ana M; Larruga, José M

    2005-08-01

    Mitochondrial DNA sequences and restriction fragment length polymorphisms were retrieved (with >80% efficiency) from a 17th-18th century sample of 213 teeth from Tenerife. The genetic composition of this population reveals an important ethnic heterogeneity. Although the majority of detected haplotypes are of European origin, the high frequency of sub-Saharan African haplotypes (15.63%), compared to that of the present-day population (6.6%), confirms the importance of the Canary Islands in the black slave trade of that epoch. The aboriginal substrate, inferred from the U6b1 haplotypes (8.59%), has also decreased due to European input. Finally, the presence of Amerindian lineages (1.5%) reveals that the Canary Islands have also received genetic flow from America.

  19. The helminth fauna of the barbary partridge Alectoris barbara in Tenerife, Canary Islands.

    Science.gov (United States)

    Foronda, P; Casanova, J C; Figueruelo, E; Abreu, N; Feliu, C

    2005-06-01

    The helminth fauna of the barbary partridge (Alectoris barbara) in Tenerife Island (Canary Archipelago) was studied from 2001 to 2002, as there were no records of helminths from this host in the Canary Islands. Seven helminth species were identified: two cestodes Choanotaenia infundibulum and Lyruterina nigropunctata, and five nematodes Aonchotheca caudinflata, Baruscapillaria obsignata, Eucoleus annulatus, Ascaridia galli and Heterakis gallinarum. Lyruterina nigropunctata, A. galli and E. annulatus are recorded for first time in A. barbara. An analysis of available data on Alectoris spp. reveals the importance of intermediate hosts such as arthropods and earthworms in the diet of partridges. Terrestrial helminths are dominant species, with monoxenous and heteroxenous species being present in similar numbers in different Alectoris species along their geographical distribution. Helminth species found in Tenerife from A. barbara are poor indicators of the host colonization from North Africa because these helminths are species that are commonly found in fowl with a cosmopolitan distribution.

  20. EVALUATING THE IMAGE OF TOURISM DESTINATIONS. THE CASE OF THE AUTONOMOUS COMMUNITY OF THE CANARY ISLANDS

    Directory of Open Access Journals (Sweden)

    Roxana - Andreea SARAGEA

    2011-12-01

    Full Text Available In the context of increased competition on the international tourism market, the assessment of destination image has become a research subject for both managers aiming to improve destination positioning and academic researchers. In order to obtain a competitive advantage, every tourist destination must identify, maintain and reinforce, through appropriate marketing policies, unique items that form and build over time "the destination' s image". Accordingly, the ultimate target of the tourist destinations' promoters should be to achieve a high level of coincidence between the promoted or projected image and the perceived image of the destination, held by potential and actual tourists. Therefore, the aim of this paper is to illustrate promotional techniques and methods used by the authorities of the Canary Islands over the years (projected image, and to identify, through a survey among the citizens of Braşov, the image that they have of the Canary Islands (perceived image.

  1. Herpesvirus infection with severe lymphoid necrosis affecting a beaked whale stranded in the Canary Islands.

    Science.gov (United States)

    Arbelo, Manuel; Sierra, Eva; Esperón, Fernando; Watanabe, Tatiane T N; Bellière, Edwige N; Espinosa de los Monteros, Antonio; Fernández, Antonio

    2010-04-01

    This report describes the pathologic findings in a single, adult female Cuvier's beaked whale Ziphius cavirostris stranded in the Canary Islands. The study indicated that this whale died with a severe, systemic, herpesviral infection and clearly exhibited lesions different from those of the fat and gas embolic syndrome described in beaked whale mass strandings associated with sonar exposure. This is the first report of a cetacean alphaherpesvirus infection of the lymphoid system in a beaked whale.

  2. Seasonal variability of the diapycnal mixing in the Canary Islands channels

    Science.gov (United States)

    Rodríguez-Santana, Angel; Marrero-Díaz, Angeles; Machín, Francisco Jose; García-Weil, Luis; Sangrà, Pablo; Vélez-Belchí, Pedro; Fraile-Nuez, Eugenio; Estrada-Allis, Sheila

    2014-05-01

    Trimonthly surveys of XBT and XCTD (Expandable Bathytermograph and Conductivity-Temperature-Depth) crossing the whole Canary Islands channels were carried out (projects TRAMIC and PROMECA) from November 2012 until September 2013 using opportunity ships (Naviera Armas Ferries). With this data set and using salinity analytical relationships (Machín et al, 2010), vertical sections of temperature and potential density were obtained for each channel and season. In order to estimate the intensity of the diapycnal mixing in the first 500 m of the pycnocline, vertical sections of Thorpe length scale, Turner angle and gradient Richardson number (from the geostrophic vertical shear) were calculated for all the cases. The first results show how the diapycnal mixing due to the vertical shear instabilities is more intense close to the islands and in summer when the seasonal pycnocline is present. Mixing due to double diffusion processes (salt fingers) was found without sizable changes in the permanent pycnocline. Net turbulence diffusivities and diapycnal diffusive fluxes with their variability spatial and temporal will be estimate for each channel taking into account that processes of double diffusion and turbulence induced by vertical shear are present at the same time. Additionally the results obtained from hydrographic data from the cruise RAPROCAN-2013 (IEO) (October 2013) around Canary Islands will be used to compare them with the channels results. This work was co-funded by Canary Government (TRAMIC project: PROID20100092), European Union (FEDER) and Spanish Government (PROMECA: CTM2008-04057/MAR and CTM2009-06993-E/MAR)

  3. New xenophytes from La Palma (Canary Islands, Spain, with emphasis on naturalized and (potentially invasive species

    Directory of Open Access Journals (Sweden)

    R. Otto

    2016-07-01

    Full Text Available Many years of field work in La Palma (western Canary Islands yielded a number of interesting new records of non-native vascular plants. Amaranthus blitoides, A. deflexus, Aptenia cordifolia, Argemone ochroleuca, Begonia schmidtiana, Capsella rubella, Cardamine hamiltonii, Centratherum punctatum, Cerastium fontanum subsp. vulgare, Chasmanthe floribunda (widely confused with C. aethiopica and Crocosmia xcrocosmiiflora in Macaronesia, Chenopodium probstii, Commelina latifolia var. latifolia, Dichondra micrantha, Dysphania anthelmintica, Epilobium ciliatum, Erigeron sumatrensis, Erodium neuradifolium, Eucalyptus globulus, Euphorbia hypericifolia, E. maculata, Gamochaeta antillana, Geranium pyrenaicum, Hedychium coronarium, Hypochaeris radicata, Kalanchoe daigremontiana, K. delagoensis, K. xhoughtonii, Kickxia commutata subsp. graeca, K. spuria subsp. integrifolia, Lactuca viminea subsp. ramosissima, Landoltia punctata, Malvastrum coromandelianum subsp. capitatospicatum, Oenothera jamesii, Orobanche nana, Oxalis latifolia, Papaver hybridum, P. setigerum, Pilea microphylla, Podranea ricasoliana, Polygonum arenastrum, Portulaca granulatostellulata, P. nicaraguensis, P. nitida, P. papillatostellulata, Rumex crispus subsp. crispus, R. pulcher subsp. pulcher, R. xpratensis, Sechium edule, Sida spinosa var. angustifolia, Silene nocturna, Solanum abutiloides, S. alatum, S. decipiens, Sonchus tenerrimus, Spergularia marina, Stellaria pallida, Tragopogon porrifolius subsp. australis, Tribulus terrestris and Trifolium repens subsp. repens are naturalized or (potentially invasive xenophytes, reported for the first time from either the Canary Islands or from La Palma. 37 additional, presumably ephemeral taxa are reported for the first time from the Canary Islands, whereas 56 ephemeral taxa are new for La Palma..

  4. Long-term (17 Ma) turbidite record of the timing and frequency of large flank collapses of the Canary Islands

    Science.gov (United States)

    Hunt, J. E.; Talling, P. J.; Clare, M. A.; Jarvis, I.; Wynn, R. B.

    2014-08-01

    turbidites on the Madeira Abyssal Plain provide a record of large-volume volcanic island flank collapses from the Canary Islands. This long-term record spans 17 Ma, and comprises 125 volcaniclastic beds. Determining the timing, provenance and volumes of these turbidites provides key information about the occurrence of mass wasting from the Canary Islands, especially the western islands of Tenerife, La Palma and El Hierro. These turbidite records demonstrate that landslides often coincide with protracted periods of volcanic edifice growth, suggesting that loading of the volcanic edifices may be a key preconditioning factor for landslide triggers. Furthermore, the last large-volume failures from Tenerife coincide with explosive volcanism at the end of eruptive cycles. Many large-volume Canary Island landslides also occurred during periods of warmer and wetter climates associated with sea-level rise and subsequent highstand. However, these turbidites are not serially dependent and any association with climate or sea level change is not statistically significant.

  5. The One-humped Camel in the Canary Islands: History and Present Status

    Directory of Open Access Journals (Sweden)

    Wilson, RT.

    2015-01-01

    Full Text Available The one-humped camel (Camelus dromedarius L. is not indigenous to the Canary Islands but based on historical references was introduced at the very beginning of the fifteenth century. The camel thrived in the subtropical dry environment. A long period of isolation from other animals of the same species meant that the animals were virtually disease free. This made the Islands an ideal base for exporting camels to new areas such that camels from the Canaries went to Peru in the sixteenth century, to Brazil in the eighteenth century, Venezuela and Bolivia in the early part of the nineteenth century and Australia in 1840. Camels went to several Caribbean islands in the middle of the nineteenth century. More recently (late twentieth and early twenty-first centuries some animals were exported from the islands to mainland Europe, notably France, Spain and the Netherlands, and to South America. Camels have been used in military operations, as transport and draught animals in support of agriculture and have found a role in the tourist industry. In early 2013 there were some 1,300 camels distributed over four of the larger islands of the archipelago in herds varying in size from a single animal to herds of as many as 150 head: a large group of about 400 heads kept in a Safari Park on the island of Fuerteventura is considered as the national conservation herd. The "Canary" camel has recently been shown to be genetically distinct from most other populations and it has been proposed that it should be designated as a distinct breed.

  6. Some additions and corrections to the Coleoptera fauna of the Canary Islands

    Directory of Open Access Journals (Sweden)

    Machado, Antonio

    2014-06-01

    Full Text Available Two endomychid species described from El Hierro (Canary Islands are removed from the Canarian fauna: Dapsa hierrensis Franz, 1976 is a synonym of Archipines intricata (Gorham, 1889, nov. syn., and the single specimen (holotype was probably collected in Central America. Dapsa curta Franz, 1976 is also poorly described and based on a single female. Without a male it is not possible to assess with full confidence if it belongs to the African genus Danae or more probably to the Oriental genus Tragoscelis, and to which species. It is for sure not a Dapsa and its Canarian origin relates probably to another labeling error of the author, who also collected in Borneo, where this latter genus is present with 5 species. Consequently, Dapsa curta Franz, 1996 is proposed as nomen dubium. Furthermore, three genera are recorded for the Canaries for the first time: Silpha puncticollis Lucas, 1854 (Silphidae, the coffee bean borer Araecerus fasciculatus (DeGeer, 1775, and Bruchela rufipes (Olivier, 1790 both Anthribidae. Only the latter species can be considered as native; the other two are introduced recently and the Coffee bean weevil could become a pest.Dos especies de endomíquidos descritos de El Hierro (islas Canarias se eliminan de la fauna canaria: Dapsa hierrensis Franz, 1976 es una sinonimia posterior de Archipines intricata (Gorham, 1889, nov. syn., y el único ejemplar conocido (holotipo fue colectado probablemente en América Central. La descripción de Dapsa curta Franz, 1976 es muy pobre y se basa en una única hembra. Sin conocer el macho es imposible determinar con garantías si se trata del género Danae o, lo más probable, del género oriental Tragoscelis, o a cuál de sus especies pertenece, si no es nueva. Es seguro que no se trata de una Dapsa y el presunto origen canario radica seguramente en otro error de etiquetado del autor, que también colectó en Borneo, donde se conocen cinco especies de Tragoscelis. En consecuencia, se propone

  7. Andromonoecy and buzz pollination in Solanum species (Solanaceae endemic to the Canary Islands

    Directory of Open Access Journals (Sweden)

    Dupont, Yoko Luise

    2006-06-01

    Full Text Available We investigated the pollination and reproductive biology of two Canary Island endemics, Solanum vespertilio and S. lidii (Solanaceae. We measured male function (pollen development, female function (fruit initiation and spatial arrangement of reproductive parts within flowers and inflorescences. Furthermore, we observed flower visitors and monitored visitation rates. Both species of Solanum display andromonoecy: Longstyled flowers are functionally hermaphrodite and borne proximally on the inflorescences, while short-styled flowers are functionally male and borne distally on inflorescences. Large bees capable of buzzing were the main flower visitors. In particular, the endemic Canarian bumblebee, Bombus terrestris canariensis, was a frequent visitor and pollen vector of S. vespertilio.Se estudiaron la polinización y biología reproductiva de dos especies endémicas de las Islas Canarias: Solanum vespertilio y S. lidii (Solanaceae. Se midieron la función masculina (desarrollo polínico, la función femenina (iniciación de fruto y la disposición espacial de los órganos reproductivos, tanto en las flores como en las inflorescencias. Se registraron además los visitantes de las flores y su frecuencia. Ambos Solanum son andromonoicos: las flores con estilo largo son funcionalmente hermafroditas y proximales en las inflorescencias, mientras que las flores con estilo corto son funcionalmente masculinas y distales en la inflorescencia. Los visitantes más asiduos fueron grandes abejas y abejorros zumbadores. El abejorro endémico Bombus terrestris canariensis, en particular, fue un visitante frecuente y un vector de polen para S. vespertilio.

  8. Long-term volcanic hazard assessment on El Hierro (Canary Islands)

    Science.gov (United States)

    Becerril, L.; Bartolini, S.; Sobradelo, R.; Martí, J.; Morales, J. M.; Galindo, I.

    2014-07-01

    Long-term hazard assessment, one of the bastions of risk-mitigation programs, is required for land-use planning and for developing emergency plans. To ensure quality and representative results, long-term volcanic hazard assessment requires several sequential steps to be completed, which include the compilation of geological and volcanological information, the characterisation of past eruptions, spatial and temporal probabilistic studies, and the simulation of different eruptive scenarios. Despite being a densely populated active volcanic region that receives millions of visitors per year, no systematic hazard assessment has ever been conducted on the Canary Islands. In this paper we focus our attention on El Hierro, the youngest of the Canary Islands and the most recently affected by an eruption. We analyse the past eruptive activity to determine the spatial and temporal probability, and likely style of a future eruption on the island, i.e. the where, when and how. By studying the past eruptive behaviour of the island and assuming that future eruptive patterns will be similar, we aim to identify the most likely volcanic scenarios and corresponding hazards, which include lava flows, pyroclastic fallout and pyroclastic density currents (PDCs). Finally, we estimate their probability of occurrence. The end result, through the combination of the most probable scenarios (lava flows, pyroclastic density currents and ashfall), is the first qualitative integrated volcanic hazard map of the island.

  9. Long-term volcanic hazard assessment on El Hierro (Canary Islands

    Directory of Open Access Journals (Sweden)

    L. Becerril

    2014-02-01

    Full Text Available Long-term hazard assessment, one of the bastions of risk-mitigation programs, is required for territorial planning and for developing emergency plans. To ensure qualitative and representative results, long-term volcanic hazard assessment requires several sequential steps to be completed, which include the compilation of geological and volcanological information, the characterization of past eruptions, spatial and temporal probabilistic studies, and the simulation of different eruptive scenarios. Despite being a densely populated active volcanic region that receives millions of visitors per year, no systematic hazard assessment has ever been conducted in the Canary Islands. In this paper we focus our attention on El Hierro, the youngest of the Canary Islands and the most recently affected by an eruption. We analyze the past eruptive activity (how, the spatial probability (where and the temporal probability (when of an eruption on the island. By studying the past eruptive behavior of the island and assuming that future eruptive patterns will be similar, we aim to identify the most likely volcanic scenarios and corresponding hazards, which include lava flows, pyroclastic fallout and pyroclastic density currents (PDCs. Finally, we estimate their probability of occurrence. The end result is the first total qualitative volcanic hazard map of the island.

  10. Lovenula (Neolovenula) alluaudi (Guerne and Richard, 1890) in the Canary Islands (Copepoda: Calanoida: Paradiaptominae). Stygofauna of the Canary Islands, 19

    NARCIS (Netherlands)

    Bowman, Thomas E.

    1990-01-01

    Lovenula (Neolovenula) alluaudi is widespread on Lanzarote, where it occurred at 22 of the 105 stations. On Fuerteventura it was found at only 2 of the 53 stations, both in the extreme northwest part of the island. It was also found in a reservoir on the south side of the small island of Alegranza.

  11. Comparative analysis of the impact of geological activity on astronomical sites of the Canary Islands, Hawaii and Chile

    CERN Document Server

    Eff-Darwich, A; Rodriguez-Losada, J A; de la Nuez, J; Hernandez-Gutierrez, L E; Romero-Ruiz, M C

    2009-01-01

    An analysis of the impact of seismic and volcanic activity was carried out at selected astronomical sites, namely the observatories of El Teide (Tenerife, Canary Islands), Roque de los Muchachos (La Palma, Canary Islands), Mauna Kea (Hawaii) and Paranal (Chile) and the candidate site of Cerro Ventarrones (Chile). Hazard associated to volcanic activity is low or negligible at all sites, whereas seismic hazard is very high in Chile and Hawaii. The lowest geological hazard in both seismic and volcanic activity was found at Roque de los Muchachos observatory, in the island of La Palma.

  12. A deep scar in the flank of Tenerife (Canary Islands): Geophysical contribution to tsunami hazard assessment

    Science.gov (United States)

    Coppo, Nicolas P.; Schnegg, Pierre-André; Falco, Pierik; Costa, Roberto

    2009-05-01

    Among the high-intensity on-Earth tsunami generating events, seismicity, submarine landslides, and volcano lateral collapses are the most important [Ward, S.H., 2001. Landslide tsunami. J. Geophy. Res. 106, 11201-11215; Holcomb, R.T., Searle, R.C., 1991. Large landslides from oceanic volcanoes. Mar. Geotech. 10, 19-32; Tinti, S., Bortolucci, E., Romagnoli, C., 2000. Computer simulations of tsunamis due to the sector collapse ar Stromboli, Italy. J. Volcano. Geotherm. Res. 96, 103-128; Ward, S.N., Day, S., 2003. Ritter Island Volcano — lateral collapse and the tsunami of 1888. Geophys. J. Int. 154, 891-902; MacGuire, W.J., 2003. Volcano instability and lateral collapse. Revista 1, 33-45]. Offshore bathymetry studies highlighted huge accumulations of large mass-waste flows (up to thousands cubic kilometres) inherited from past lateral collapses or submarine landslides [ Le Friant, A., Boudon, G., Deplus, C., Villemant, B., 2003. Large-scale flank collapse events during the activity of Montagne Pelée, Martinique, Lesser Antilles. J. Geophys. Res. 108, ECV13; Moore, J.G. et al., 1989. Prodigious submarine Landslides on the Hawaiian ridge. J. Geophys. Res. 94, 17465-17484] which spread over more than 100 km off the northern Tenerife (Canary Islands) coastline [Watts, A.B., Masson, D.G., 1995. A giant landslide on the north flank of Tenerife, Canary Islands. J. Geophys. Res. 100, 24487-24498]. Although mechanics and dynamics triggering such catastrophic events follow from combined complex processes and interactions [Hürlimann, M., Garcia-Piera, J.-O., Ledesma, A., 2000. Causes and mobility of large volcanic landslides: application to Tenerife, Canary Islands. J. Volcano. Geotherm. Res. 103, 121-134; Masson, D.G. et al., 2002. Slope failures on the flanks of the western Canary Islands. Earth-Sci. Rev. 57, 1-35; Reid, M.E., Sisson, T.W., Brien, D.L., 2001. Volcano collapse promoted by hydrothermal alteration and edifice shape, Mount Rainier, Washington. Geology 29, 779

  13. Comparison between the landhoppers (Amphipoda: Talitridae) of the genus Orchestia from Tenerife (Canary Islands) and the Azores

    NARCIS (Netherlands)

    Stock, J.H.; Boxshall, G.A.

    1989-01-01

    The terrestial Orchestia from Tenerife (Canary Islands), currently recorded as O. chevreuxi De Guerne, 1887, is compared with material from the terra typica, the island of Faial in the Azores. It is concluded that the Tenerife populations belong to a different species, which we describe as O. guanch

  14. Isolation and characterization of Acanthamoeba strains from soil samples in Gran Canaria, Canary Islands, Spain.

    Science.gov (United States)

    Reyes-Batlle, María; Todd, Cheridah D; Martín-Navarro, Carmen M; López-Arencibia, Atteneri; Cabello-Vilchez, Alfonso Martín; González, Ana C; Córdoba-Lanús, Elizabeth; Lindo, John F; Valladares, Basilio; Piñero, José E; Lorenzo-Morales, Jacob

    2014-04-01

    Free-living Amoebae of Acanthamoeba genus include non-pathogenic and pathogenic strains that are currently classified in 18 different genotypes, T1-T18. In this study, a survey was carried out to evaluate the presence of Acanthamoeba strains in soil samples collected between 2012 and 2013 in Gran Canaria Island, Canary Islands, Spain. Samples were inoculated onto non-nutrient agar (NNA) plates and were checked for the presence of Acanthamoeba. Identification of Acanthamoeba strains was based on the morphology of the cyst and trophozoite forms. Subsequently, positive samples were cloned for their molecular characterization at the genotype level by sequencing the DF3 region located in the 18S rDNA gene of Acanthamoeba as previously described. Sequencing results revealed the presence of T2, T5 and T4 genotypes within the studied samples. To the best of our knowledge, this is the first report demonstrating the presence of Acanthamoeba in Gran Canaria Island and the first study at the genotype level in the Canary Islands.

  15. Crude oil as a stranding cause among loggerhead sea turtles (Caretta caretta) in the Canary Islands, Spain (1998-2011).

    Science.gov (United States)

    Camacho, María; Calabuig, Pascual; Luzardo, Octavio P; Boada, Luis D; Zumbado, Manuel; Orós, Jorge

    2013-07-01

    We report the number of strandings caused by crude oil among loggerhead turtles (Caretta caretta) in the Canary Islands between 1998 and 2011 and analyze the impact of the designation of the Canary Islands as a Particularly Sensitive Sea Area (PSSA) in 2005. Among 1,679 stranded loggerhead turtles, 52 turtles stranded due to crude oil (3.1%). The survival rate of the turtles stranded by crude oil was 88%. All turtles that died because of crude oil stranding had signs of ingestion of crude oil and lesions, included esophageal impaction, necrotizing gastroenteritis, necrotizing hepatitis, and tubulonephrosis. The number of strandings caused by crude oil after 2005 was significantly lower than it was before 2006. We show that the designation of the Canary Islands as a PSSA in 2005 by the International Maritime Organization was associated with a reduction of sea turtle strandings caused by crude oil.

  16. Arrival of radionuclides released by the Fukushima accident to Tenerife (Canary Islands).

    Science.gov (United States)

    López-Pérez, M; Ramos-López, R; Perestelo, Nayra R; Duarte-Rodriguez, X; Bustos, J J; Alonso-Pérez, S; Cuevas, E; Hernández-Armas, J

    2013-02-01

    Two weeks after the accident at the Fukushima-Daichi nuclear power plant, 131I, 137Cs and 134Cs activities were measured in two different stations located in Tenerife (Canary Islands), situated at 300 (FIMERALL) and 2400 (IZAÑA) m.a.s.l, respectively. Peak measured activity concentrations were: 1.851 mBq/m3 (131I); 0.408 mBq/m3 (137Cs) and 0.382 mBq/m3 (134Cs). The activities measured at the FIMERALL station were always higher than at IZAÑA station, suggesting that the radioactive plume arrived to the island associated with low altitude air masses. Simulations of potential dispersion of the radioactive cloud (137Cs) after the nuclear accident in reactor Fukushima I show that radioactive pollution reached remote regions such as the Canary Islands in the Eastern subtropical North Atlantic. The corresponding effective dose to the local population was 1.17 nSv, a value less than one millionth of the annual limit for the general public. Therefore, there was no risk to public health.

  17. A Subtropical Cyclone in the Canary Islands: the October 2014 event

    Science.gov (United States)

    Quitian, Lara; Martin, Maria Luisa; Jesús González-Alemán, Juan; Santos-Muñoz, Daniel; Valero Rodríguez, Francisco

    2016-04-01

    Depending on the thermal structure and dynamics, there are different types of cyclones in the troposphere. Subtropical cyclones (STC) are low pressure systems that share tropical and extratropical characteristics, having hybrid thermal structures. In October 2014, a cyclonic system landfall the Canary Islands, causing widespread damages. The system began to develop in October 18 and its effects lasted until October 21. Here, the diagnosis and identification of such cyclone as STC is carried out, examining its dynamical and thermal evolution. Diverse fields have been obtained from three different numerical models, and several diagnostic tools and cyclone phase space diagrams have been used. The cyclone evolved from a typical extratropical cyclone, detached from the atmospheric circulation which was highly meridional and became a stationary cut-off low. The meridional intrusion of the trough as well as a low-level baroclinic zone favored the formation of a STC northwestern of the Canary Islands. Several cyclone phase space diagrams are used to classify the cyclone as a STC, highlighting a deep cold core in its early stages that develops into a shallow warm core. High potential vorticity areas associated with the cyclone promoted strong winds and precipitation over the Islands. Throughout the event, an increased conditional instability is observed in the different soundings, leading to strong vertical wind shear. Moreover, relatively warm sea surface temperature is obtained, establishing the conditions to favor the organization of long-lived convective structures.

  18. Outbreak of Shigella sonnei in a rural hotel in La Gomera, Canary Islands, Spain.

    Science.gov (United States)

    Alcoba-Flórez, Julia; Pérz-Roth, Eduardo; González-Linares, Sandra; Méndez-Alvarez, Sebastián

    2005-06-01

    Shigella sonnei is a significant cause of gastroenteritis in both developing and industrialized countries. Knowledge of the diversity and antimicrobial susceptibility of the bacterium may be helpful in the management of both individual cases and outbreaks. This study was undertaken to evaluate the molecular epidemiology of an outbreak of diarrhea due to S. sonnei. The outbreak involved 14 of 28 (50%) tourists in a small rural hotel in La Gomera, Canary Islands, Spain. All of the S. sonnei isolates recovered had the same antimicrobial susceptibility and pulsed-field gel electrophoresis patterns, suggesting that the outbreak was produced by a single strain.

  19. Pulmonary angiomatosis and hemangioma in common dolphins (Delphinus delphis) stranded in Canary Islands.

    Science.gov (United States)

    Díaz-Delgado, Josué; Arbelo, Manuel; Sacchini, Simona; Quesada-Canales, Óscar; Andrada, Marisa; Rivero, Miguel; Fernández, Antonio

    2012-08-01

    Vascular tumors and disorders, like angiomatosis, are rarely described in cetacean species. A retrospective histological study was carried out on lung samples from 35 common dolphins (Delphinus delphis) stranded in the Canary Islands coasts looking for morphological vascular changes and likely related causes. Twenty-five out of thirty-five (71%) common dolphins showed focal or multifocal angiomatosis-like lesions. A high association between this type of vascular proliferation and parasitic infestation was observed. In addition, a single pulmonary cavernous hemangioma not previously reported in common dolphins is presented.

  20. Ciguatera fish poisoning on the West Africa Coast: An emerging risk in the Canary Islands (Spain).

    Science.gov (United States)

    Boada, Luis D; Zumbado, Manuel; Luzardo, Octavio P; Almeida-González, Maira; Plakas, Steven M; Granade, Hudson R; Abraham, Ann; Jester, Edward L E; Dickey, Robert W

    2010-12-01

    Ciguatera fish poisoning (CFP) is endemic in certain tropical and subtropical regions of the world. CFP had not been described on the West Africa Coast until a 2004 outbreak in the Canary Islands. In 2008-2009, two additional outbreaks of ciguatera occurred. Individuals afflicted had consumed lesser amberjack (Seriola rivoliana) captured from nearby waters. Caribbean ciguatoxin-1 (C-CTX-1) was confirmed in fish samples by LC-MS/MS. Ciguatoxic fish in this region may pose a new health risk for the seafood consumer.

  1. Hybrid wind diesel system for a village in the Canary Islands. Operation results and conclusions

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, I.; Arribas, L.; Gonzalez, A. [CIEMAT-IER, Madrid (Spain)] [and others

    1996-12-31

    The first release from the operation data from the Hybrid Wind Diesel System carried-out one year ago in Fuerteventura (Canary Islands) are available. In this paper the results of the detailed analysis are presented, concerning the impact of the parameters from the different systems in the whole system. The performance of the operation strategy is demonstrated with computational results. Comparisons between different function modes are also included. These results show that the feasibility of the project is essentially affected by the wind energy penetration and by the reliability of the system. Finally, system energy balances will be given. (Author)

  2. Groundwater flow in a relatively old oceanic volcanic island: the Betancuria area, Fuerteventura Island, Canary Islands, Spain.

    Science.gov (United States)

    Herrera, Christian; Custodio, Emilio

    2014-10-15

    The island of Fuerteventura is the oldest of the Canary Islands' volcanic archipelago. It is constituted by volcanic submarine and subaerial activity and intrusive Miocene events, with some residual later volcanism and Quaternary volcanic deposits that have favored groundwater recharge. The climate is arid, with an average rainfall that barely attains 60 mm/year in the coast and up to 200 mm/year in the highlands. The aquifer recharge is small but significant; it is brackish due to large airborne atmospheric salinity, between 7 and 15 gm(-2)year(-1) of chloride deposition, and high evapo-concentration in the soil. The average recharge is estimated to be less than about 5 mm/year at low altitude and up to 10 mm/year in the highlands, and up to 20 mm/year associated to recent lava fields. Hydrochemical and water isotopic studies, supported by water table data and well and borehole descriptions, contribute a preliminary conceptual model of groundwater flow and water origin in the Betancuria area, the central area of the island. In general, water from springs and shallow wells tends to be naturally brackish and of recent origin. Deep saline groundwater is found and is explained as remnants of very old marine water trapped in isolated features in the very low permeability intrusive rocks. Preliminary radiocarbon dating indicates that this deep groundwater has an apparent age of less than 5000 years BP but it is the result of mixing recent water recharge with very old deep groundwater. Most of the groundwater flow occurs through the old raised volcanic shield of submarine and subaerial formations and later Miocene subaerial basalts. Groundwater transit time through the unsaturated zone is of a few decades, which allows the consideration of long-term quasi-steady state recharge. Transit times are up to a few centuries through the saturated old volcanics and up to several millennia in the intrusive formations, where isolated pockets of very old water may exist.

  3. Reproductive phenology of three species of Gelidiales (Rhodophyta in two macroalgal communities from Tenerife (Atlantic Ocean, Canary Islands, Spain

    Directory of Open Access Journals (Sweden)

    Polifrone, Milena

    2012-12-01

    Full Text Available The reproductive phenology of three species of Gelidiales, Gelidium canariense, Gelidium arbuscula and Pterocladiella capillacea, was analysed seasonally for a period of one year in two localities on the West coast of Tenerife (Atlantic Ocean, Canary Islands, Spain. Considerations are provided on sex ratio, maximum length and branch order of uprights and on the length of the thalli for each sexual and asexual phase of the Canary Islands populations. The three species were characterized by a high percentage of tetrasporophytes, while female and male gametophytes have been observed only in little proportion. Only G. canariense showed gametophytes in all seasons while the occurrence of gametophytes in G. arbuscula and Pterocladiella capillacea demonstrated a clear seasonality.

    La fenología reproductiva de tres especies de Gelidiales, Gelidium canariense, Gelidium arbuscula y Pterocladiella capillacea, ha sido analizada estacionalmente por un periodo de un año en dos localidades de la costa este de Tenerife (Oceano Atlántico, Islas Canarias, España. Se realizan consideraciones sobre sex ratio, longitud máxima y orden de ramificación de los ramets y se aporta información sobre la longitud del talo por cada fase sexual y asexual de las poblaciones canarias. Las tres especies se caracterizan por presentar un elevado porcentaje de tetrasporofitos, mientras que los gametofitos masculinos y femeninos han sido observados en proporciones reducidas. Sólo G. canariense presenta gametofitos en todas las estaciones, mientras que en G. arbuscula y Pterocladiella capillacea demostraban una clara estacionalidad.

  4. Acanthamoeba genotypes T2, T4, and T11 in soil sources from El Hierro island, Canary Islands, Spain.

    Science.gov (United States)

    Reyes-Batlle, María; Zamora-Herrera, Jonadab; Vargas-Mesa, Alejandro; Valerón-Tejera, Marco Antonio; Wagner, Carolina; Martín-Navarro, Carmen Ma; López-Arencibia, Atteneri; Sifaoui, Ines; Martínez-Carretero, Enrique; Valladares, Basilio; Piñero, José E; Lorenzo-Morales, Jacob

    2016-08-01

    The genus Acanthamoeba includes pathogenic strains which are causative agents of keratitis and encephalitis that often may end fatal in humans and other animals. In the present study, forty soil samples were collected in the island of El Hierro, Canary Islands, Spain, and checked for the presence of Acanthamoeba. Samples were cultivated onto 2 % non-nutrient agar plates seeded with a layer of heat killed Escherichia coli. Amplification by PCR and sequencing of the DF3 region of the 18S rDNA of Acanthamoeba was carried out in order to confirm morphological identification of the amoebae. Furthermore, Acanthamoeba spp. was isolated from 47.5 % of soil samples. Moreover, genotypes T2, T4, and T11 were identified in these samples. To the best of our knowledge, this is the first study to establish genotypes T2, T4, and T11 in soil sources from El Hierro island.

  5. Extinction of endemic vertebrates on islands : The case of the giant rat Canariomys bravoi (Mammalia, Rodentia) on Tenerife (Canary Islands, Spain)

    NARCIS (Netherlands)

    Bocherens, Herve; Michaux, Jacques; Talavera, Francisco Garcia; Van der Plicht, Johannes

    2006-01-01

    Fossil bone collagen (14)C dating and delta(13)C and delta(15)N isotopic measurements of the rodent Canariomys bravoi from Tenerife (Canary Islands.. Spain) were used to test two different hypotheses about the causes of extinctions of endemic vertebrates on islands. climate versus humans. For the Te

  6. The sub-volcanic system of El Hierro, Canary Islands

    Science.gov (United States)

    Galindo, I.; Becerril, L.; Gudmundsson, A.

    2012-04-01

    The main volcanotectonic structures of El Hierro are three rift zones, trending northeast, west, and south. Most of the eruptions in El Hierro within these zones are basaltic fissure eruptions fed by subvertical dykes. The dykes appear as close to collinear or slightly offset segments, their surface expressions being clusters of cinder cones and eruptive vents. Three large landslides, referred to as El Golfo, El Julan, and Las Playas, have eroded the areas between rift axes and provide exposures that make it possible to provide a three-dimensional view of the uppermost part of the sub-volcanic system. Here we report the results of a structural study of the sub-volcanic system as obtained through the analysis of dykes and eruptive vents. The data obtained from surface outcrops have been combined with data from subsurface water galleries. More than 600 eruptive vents and 625 dykes have been studied in detail to characterise the subvolcanic system of the island. Using cinder-cone and other eruptive-vent alignments it has been possible to infer 115 eruptive fissures with lengths that range from 40 m to 2200 m. NE-SW trending volcanic fissures and dykes are common on the entire island and predominate in the northeast rift zone. The main strike of the dykes and fissures in the south and west rift zones are approximately NNW-SSE and E-W, respectively. However, in the west rift zone, eruptive fissures display a fan distribution with directions that range from N43°E to N124°E. Volcanic fissures within the El Golfo landslide valley trend parallel to the head scarp, except those that are close to the head of the valley, many of which are perpendicular to the scarp. Dykes show a radial distribution in the head scarp of the El Golfo landslide. Three feeder-dykes directly connected with their lava flows have been identified in El Hierro. Feeder dykes are difficult to observe in the field but provide important information when their lengths and thicknesses can be measured

  7. Groundwater flow in a relatively old oceanic volcanic island: The Betancuria area, Fuerteventura Island, Canary Islands, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Herrera, Christian, E-mail: cherrera@ucn.cl [Universidad Católica del Norte, Av. Angamos 0610, Antofagasta (Chile); Custodio, Emilio [Department of Geo-Engineering, Technical University of Catalonia (UPC), Barcelona (Spain)

    2014-10-15

    The island of Fuerteventura is the oldest of the Canary Islands' volcanic archipelago. It is constituted by volcanic submarine and subaerial activity and intrusive Miocene events, with some residual later volcanism and Quaternary volcanic deposits that have favored groundwater recharge. The climate is arid, with an average rainfall that barely attains 60 mm/year in the coast and up to 200 mm/year in the highlands. The aquifer recharge is small but significant; it is brackish due to large airborne atmospheric salinity, between 7 and 15 g m{sup −2} year{sup −1} of chloride deposition, and high evapo-concentration in the soil. The average recharge is estimated to be less than about 5 mm/year at low altitude and up to 10 mm/year in the highlands, and up to 20 mm/year associated to recent lava fields. Hydrochemical and water isotopic studies, supported by water table data and well and borehole descriptions, contribute a preliminary conceptual model of groundwater flow and water origin in the Betancuria area, the central area of the island. In general, water from springs and shallow wells tends to be naturally brackish and of recent origin. Deep saline groundwater is found and is explained as remnants of very old marine water trapped in isolated features in the very low permeability intrusive rocks. Preliminary radiocarbon dating indicates that this deep groundwater has an apparent age of less than 5000 years BP but it is the result of mixing recent water recharge with very old deep groundwater. Most of the groundwater flow occurs through the old raised volcanic shield of submarine and subaerial formations and later Miocene subaerial basalts. Groundwater transit time through the unsaturated zone is of a few decades, which allows the consideration of long-term quasi-steady state recharge. Transit times are up to a few centuries through the saturated old volcanics and up to several millennia in the intrusive formations, where isolated pockets of very old water may

  8. Assessment of anticoagulant rodenticide exposure in six raptor species from the Canary Islands (Spain).

    Science.gov (United States)

    Ruiz-Suárez, Norberto; Henríquez-Hernández, Luis A; Valerón, Pilar F; Boada, Luis D; Zumbado, Manuel; Camacho, María; Almeida-González, Maira; Luzardo, Octavio P

    2014-07-01

    Anticoagulant rodenticides are highly toxic compounds that are widely used for pest control of rodents, but that also may threaten the wildlife's health. This work aimed to assess the exposure to first- and second-generation anticoagulant rodenticides (ARs) in six birds of prey species from the Canary Islands (Spain). The concentrations of seven widely used ARs were determined by LC-MS/MS in 104 liver samples of six species of birds of prey (Buteo buteo, Accipiter nisus, Falco pelegrinoides, Falco tinnunculus, Asio otus, and Tyto alba). We determined that 61% of the livers had detectable residues of at least one AR. The most frequently detected AR was bromadiolone, which was detected in 60.3% of the positive cases. The detection frequencies of these compounds varied widely, depending on the species. More than 75% of the A. nisus, T. alba, and A. otus individuals had detectable rodenticide residues in the liver. However, F. tinnunculus exhibited the highest concentrations of AR, with median values above 100 ng/g w.w. We did not detect first-generation ARs in any of the samples. When grouped, nocturnal species exhibited higher AR concentrations than diurnal species (Praptors on the Canary Islands. Our findings require authorities to ban or strictly control the use of these rodenticides in the natural environment for the conservation of raptors and other predatory species.

  9. Recent changes and drivers of the atmospheric evaporative demand in the Canary Islands

    Science.gov (United States)

    Vicente-Serrano, Sergio M.; Azorin-Molina, Cesar; Sanchez-Lorenzo, Arturo; El Kenawy, Ahmed; Martín-Hernández, Natalia; Peña-Gallardo, Marina; Beguería, Santiago; Tomas-Burguera, Miquel

    2016-08-01

    We analysed recent evolution and meteorological drivers of the atmospheric evaporative demand (AED) in the Canary Islands for the period 1961-2013. We employed long and high-quality time series of meteorological variables to analyse current AED changes in this region and found that AED has increased during the investigated period. Overall, the annual ETo, which was estimated by means of the FAO-56 Penman-Monteith equation, increased significantly by 18.2 mm decade-1 on average, with a stronger trend in summer (6.7 mm decade-1). In this study we analysed the contribution of (i) the aerodynamic (related to the water vapour that a parcel of air can store) and (ii) radiative (related to the available energy to evaporate a quantity of water) components to the decadal variability and trends of ETo. More than 90 % of the observed ETo variability at the seasonal and annual scales can be associated with the variability in the aerodynamic component. The variable that recorded more significant changes in the Canary Islands was relative humidity, and among the different meteorological factors used to calculate ETo, relative humidity was the main driver of the observed ETo trends. The observed trend could have negative consequences in a number of water-depending sectors if it continues in the future.

  10. Pathology and causes of death of stranded cetaceans in the Canary Islands (1999-2005).

    Science.gov (United States)

    Arbelo, Manuel; Los Monteros, Antonio Espinosa de; Herráez, Pedro; Andrada, Marisa; Sierra, Eva; Rodríguez, Francisco; Jepson, Paul D; Fernández, Antonio

    2013-03-26

    Between 1999 and 2005, 233 stranded cetaceans (comprising 19 species) were reported in the waters of the Canary Islands. Of these, 138/233 (59.2%) were subjected to a complete or partial standardized necropsy, including 4 Balaenopteridae, 9 Physeteridae, 8 Kogiidae, 27 Ziphiidae and 90 Delphinidae. Of these, 46/138 (33.3%) cetaceans were diagnosed with anthropogenic pathological categories (i.e. the cause of death was anthropogenic). These included fishing interaction (bycatch) (19 individuals), 'atypical' mass stranding events linked to naval exercises (13), ship collisions (8) and other anthropogenic-related pathology (6). 'Natural' (i.e. non-anthropogenic) causes of death accounted for another 82/138 (59.4%) cases, including infectious and non-infectious diseases (63), neonatal pathology (8), intra- and interspecific interactions (6) and mass strandings (5). The cause(s) of death could not be determined in 10/138 (7.3%) necropsied animals. The most common causes of death were ship collisions in 6/9 (66.6%) Physeteridae, 'atypical' mass stranding linked to naval exercises in 13/27 (48.1%) Ziphiidae, and 'natural' infectious and non-infectious diseases in 55/90 (61.1%) Delphinidae. Interaction with fishing activities was established as cause of death in 15/90 (16.7%) Delphinidae. These data show that a range of anthropogenic and natural single and mass mortality events occur in multiple cetacean species stranded in the Canary Islands.

  11. Unusual Vermamoeba Vermiformis Strain Isolated from Snow in Mount Teide, Tenerife, Canary Islands, Spain

    Directory of Open Access Journals (Sweden)

    Maria Reyes-Batlle

    2015-10-01

    Full Text Available Background: Free-living amoebae (FLA are protozoa that are widely distributed in the environment mainly in water and soil related habitats. Thermophilic amoebae are among the most common FLA in water bodies, being Vermamoeba vermiformis one of the most common species reported worldwide from these sources. Interestingly, V. vermiformis has often been reported to survive at high temperatures and osmotic pressure worldwide.Materials and Methods: In this study, snow samples were collected from Mount Teide, Tenerife, Canary Islands during the winter season of 2014. The samples were culture on non nutrient agar plates and checked daily for the presence of FLA. After a week, V. vermiformis amoebae were observed in the plates incubated at room temperature and 37ºC.Results: Molecular characterization was carried out by amplifying the 18S rDNA gene and DNA sequencing, confirmed that the isolated strain belonged to Vermamoeba vermiformis species.Conclusion: To the best of our knowledge, this is the first report of Vermamoeba vermiformis isolation from such an inusual habitat (low temperatures and high altitude and the first report of these species in the Canary islands.

  12. Pronounced fixation, strong population differentiation and complex population history in the Canary Islands blue tit subspecies complex.

    Directory of Open Access Journals (Sweden)

    Bengt Hansson

    Full Text Available Evolutionary molecular studies of island radiations may lead to insights in the role of vicariance, founder events, population size and drift in the processes of population differentiation. We evaluate the degree of population genetic differentiation and fixation of the Canary Islands blue tit subspecies complex using microsatellite markers and aim to get insights in the population history using coalescence based methods. The Canary Island populations were strongly genetically differentiated and had reduced diversity with pronounced fixation including many private alleles. In population structure models, the relationship between the central island populations (La Gomera, Tenerife and Gran Canaria and El Hierro was difficult to disentangle whereas the two European populations showed consistent clustering, the two eastern islands (Fuerteventura and Lanzarote and Morocco weak clustering, and La Palma a consistent unique lineage. Coalescence based models suggested that the European mainland forms an outgroup to the Afrocanarian population, a split between the western island group (La Palma and El Hierro and the central island group, and recent splits between the three central islands, and between the two eastern islands and Morocco, respectively. It is clear that strong genetic drift and low level of concurrent gene flow among populations have shaped complex allelic patterns of fixation and skewed frequencies over the archipelago. However, understanding the population history remains challenging; in particular, the pattern of extreme divergence with low genetic diversity and yet unique genetic material in the Canary Island system requires an explanation. A potential scenario is population contractions of a historically large and genetically variable Afrocanarian population, with vicariance and drift following in the wake. The suggestion from sequence-based analyses of a Pleistocene extinction of a substantial part of North Africa and a Pleistocene

  13. Effect of wildfires on the genetic microbial diversity in forest soils from Canary Islands (Spain

    Directory of Open Access Journals (Sweden)

    J. Rodríguez

    2013-05-01

    Full Text Available Wildfires produce several ecological and environmental impacts on the physical and chemical soil characteristics, as well as on the properties and dynamics of soil microbial populations. Microorganisms are good indicators of ecosystem function and sustainability and therefore the studies about the impact of fire on microbial communities is relevant to understand the role of fire in ecosystem functioning. Although several authors have provided data about total microbial biomass and activity in soils affected by fires, there is little information about the composition and evolution of soil microbial populations after the passage of fire. In this work the effect of wildfires on the genetic diversity of microbial populations in soils from the island of Tenerife (Canary Islands, Spain is studied. The final objective was to get information about the recovery of soil functionality after wildfires.

  14. Shallow seismic imaging of flank collapse structures in oceanic island volcanoes: Application to the Western Canary Islands

    Science.gov (United States)

    Sanchez, L.; González, P.; Tiampo, K. F.

    2013-12-01

    Volcanic flank collapse counts among the many hazards associated with volcanic activity. This type of event involves the mobilization of large volumes, producing debris avalanches. It affects mostly oceanic island volcanoes, involving the potential for tsunami occurrence. Geophysical imaging can illuminate subvolcanic features such as volcano-tectonic structures, magmatic plumbing systems or differences in rock type. The most commonly used geophysical methods are gravity, electromagnetics and seismics. In particular, seismic measurements quantify anomalies in seismic waves propagation velocities and can be used to obtain information on the subsurface arrangement of different materials. In the Western Canary Islands, the Cumbre Vieja volcano in La Palma (Canary Islands) has been proposed to be near the collapse stage. Previous geophysical studies that have been carried out on the flank of the volcano comprise gravity and electromagnetic methods. These types of surveys gather information on the deep structures of the volcano (1-2 km). In this project, we complement previous studies by using seismic methods to investigate the near-surface seismic structure of the Cumbre Vieja fault system (La Palma Island) and the structure of the well-developed San Andres fault system (El Hierro Island). We aim to compare the Cumbre Vieja and San Andres fault systems to infer the degree of maturity of collapse structures. We carried out reflection and refraction seismic surveys in order to image approximately the first 10 meters of the subsurface. We used 24 low frequency (4,5 Hz) geophones as receivers and a sledge hammer as the seismic source. The survey lines were located across visible parts of the fault systems at the Cumbre Vieja volcano and the San Andres fault in El Hierro. Here, we present the survey setup and results from the preliminary analysis of the data.

  15. Floating sandstones off El Hierro (Canary Islands, Spain: the peculiar case of the October 2011 eruption

    Directory of Open Access Journals (Sweden)

    V. R. Troll

    2011-12-01

    Full Text Available The eruption that started off the south coast of El Hierro, Canary Islands, in October 2011 has emitted intriguing eruption products found floating in the sea. These specimens appeared as floating volcanic "bombs" that have in the meantime been termed "restingolites" (after the close-by village of La Restinga and exhibit cores of white and porous pumice-like material. Currently the nature and origin of these "floating stones" is vigorously debated among researchers, with important implications for the interpretation of the hazard potential of the ongoing eruption. The "restingolites" have been proposed to be either (i juvenile high-silica magma (e.g. rhyolite, (ii remelted magmatic material (trachyte, (iii altered volcanic rock, or (iv reheated hyaloclastites or zeolite from the submarine slopes of El Hierro. Here, we provide evidence that supports yet a different conclusion. We have collected and analysed the structure and composition of samples and compared the results to previous work on similar rocks found in the archipelago. Based on their high silica content, the lack of igneous trace element signatures, and the presence of remnant quartz crystals, jasper fragments and carbonate relicts, we conclude that "restingolites" are in fact xenoliths from pre-island sedimentary rocks that were picked up and heated by the ascending magma causing them to partially melt and vesiculate. They hence represent messengers from depth that help us to understand the interaction between ascending magma and crustal lithologies in the Canary Islands as well as in similar Atlantic islands that rest on sediment/covered ocean crust (e.g. Cape Verdes, Azores. The occurrence of these "restingolites" does therefore not indicate the presence of an explosive high-silica magma that is involved in the ongoing eruption.

  16. The 1677 eruption of La Palma, Canary Islands

    Directory of Open Access Journals (Sweden)

    Rodríguez Badiola, E.

    1996-08-01

    Full Text Available The 1677 volcanic eruption, located close to the town of Fuencaliente at the south end of La Palma, has been associated with the large volcanic cone of San Antonio, an emission centre showing relatively high energy phreatomagmatic phases. However, detailed geological mapping and a reinterpretation of available eye-witness accounts elearly prove the San Antonio emission centre to be a preexisting volcano related to an eruption that occurred several thousands years earlier. The 1677 eruption, or Volcán de Fuencaliente is a low magnitude eruption composed of a small strombolian vent and a cluster of aligned spatter vents. About 75-125 x 106 m3 of lavas from these spatter vents covered an area of 4.5 x 106 m2 and formed a wide coastal platform with 1.6 x 106 m2 of new land gained from the sea. This modest magnitude eruption is in better accord with the negligible damage caused to the area reported in the contemporary accounts. This revision of the 1677 eruption and its magnitude is relevant for the precise reconstruction of the recent volcanism of La Palma and the correct definition of volcanic hazards in the island.La erupción de 1677, localizada cerca de la población de Fuencaliente en el S de la isla de La Palma, ha sido asociada hasta ahora con el cono volcánico denominado San Antonio. Este centro de emisión presenta fases eruptivas de energía relativamente elevada. El estudio geológico de detalle de esta erupción y la reinterpretación de los relatos de la época indican que el volcán San Antonio es, en realidad, un aparato volcánico preexistente, relacionado con algún episodio eruptivo de varios miles de años de antigüedad. La verdadera erupción de 1677 o Volcán de Fuencaliente, es de baja magnitud y está formada por pequeños centros eruptivos estrombolianos y conos alineados de escorias. El volumen de lavas emitidas es de unos 75-125 x 106 m3 y cubre una extensión de aproximadamente 4.5 x 106 m2, de los cuales 1.6 x 106 m2

  17. Felsic volcanism in a basic shield (El Hierro, Canary Islands). Implications in terms of volcanic hazards.

    Science.gov (United States)

    Pedrazzi, Dario; Becerril Carretero, Laura; Martí Molist, Joan; Meletlidis, Stavros; Galindo Jiménez, Inés

    2014-05-01

    El Hierro, the southwesternmost and smallest island of the Canary Archipelago, is a complex basaltic shield volcano characterized by mainly effusive volcanism with both Strombolian and Hawaiian activity. Explosive felsic volcanism is not a common feature of the archipelago and, so far, it has only been reported on the central islands of Tenerife and Gran Canaria, where it has been responsible for the formation of large central volcanic complexes. The presence of felsic rocks on the other islands of the archipelago and specifically on El Hierro is mostly restricted to subvolcanic intrusions and a few lava flows, generally associated with the oldest parts of the islands. We hereby report the presence of a trachytic pumice deposit on the island of El Hierro, referred to here as the Malpaso Member. A detailed stratigraphic, lithological, and sedimentological study was carried out on the deposits of this explosive episode of felsic composition, which is the only one found on the Canary Islands apart from those of Gran Canaria and Tenerife. Four different subunits were identified on the basis of their lithological and granulometrical characteristics. The products of the eruption correspond to a single eruptive event and cover an area of about 13 km2. This deposit originated from a base-surge-type explosive eruption with a subsequent radial emplacement of dilute PDC currents, was emplaced from the vent that would have been located in a similar position to the volcano of Tanganasoga. The low vesicularity of juvenile fragments and the morphological characteristics of the fine particles, as well as the high proportion of lithic fragments and the ash-rich nature of the deposit, suggest that magma/water interaction controlled the dynamics of the eruption. This study demonstrates that magmas from El Hierro could have the potential for producing an explosive eruption, in an environment in which the majority of the eruptions are basaltic and effusive in nature. Bearing in mind

  18. Petrological and geochemical studies of mantle xenoliths from La Palma, Canary Islands

    Science.gov (United States)

    Janisch, Astrid; Ntaflos, Theodoros

    2015-04-01

    La Palma is the second youngest island, after El Hierro, of the Canary archipelago. The archipelago consists of seven large islands, forming an east-west-trending island chain, and several seamounts. All together they form a volcanic belt of around 800 km length and 450 km width, which presumably comprises roughly the Canary hotspot. The islands are located off the western coast of Morocco, Africa. The distance ranges from 100 km to 500 km. Concurrently with the distance, subaerial volcanism age progresses from the oldest lava in the east to the youngest in the west of the archipelago. Presently, La Palma is in the shield building stage of growth (alongside with El Hierro and Tenerife) and is furthermore the fastest growing island of the Canary archipelago. Historical volcanic eruptions are restricted on the younger islands, La Palma and El Hierro, with the last eruption at the south end of La Palma in 1971. Mantle xenoliths described in this work were collected at the slopes of San Antonio Volcano, Fuencaliente, brought to the surface during the 1677/1678 eruption. The mantle xenolith collection comprises sp-lherzolites, sp-harzburgites and pyroxenites. The texture can be distinguished between coarse-grained matrix and fine-grained veins in various thicknesses, mostly with olivine and pyroxene but also with amphibole, phlogopite as well as apatite. Mineral analyses reveal the existence of primary and secondary ol, cpx and opx. Primary ol has Fo contents of 89.2 to 91.7 and NiO ranging from 0.3 to 0.45 wt.%, whereas secondary ol show Fo values of 78.4 to 91.9 but with NiO below 0.3 wt.%. Primary cpx are predominantly Cr-Diopsides with En48.7-51.9-Wo43.5-44.3-Fs4.1-4.9 and Mg# of 91.5 to 92.4. Secondary cpx, primarily Ti-Augit, display En36.7-44.4-Wo47.7-49.6-Fs6.7-13.0 and Mg# of 75.3 to 90.8. Primary opx compositions are in range of En89.3-90.6-Wo1.3-1.5-Fs8.1-9.3 with Mg# between 90.7 and 92.0. Secondary opx exhibit En88.7-89.2-Wo1.7-1.9-Fs9.1-9.5 and Mg# of 90

  19. Psammogammarus stocki n. sp. (Crustacea, Amphipoda, Melitidae) from beach interstitia on Tenerife. Stygofauna of the Canary Islands, 21

    NARCIS (Netherlands)

    Vonk, Ronald

    1990-01-01

    A description is given of Psammogammarus stocki n. sp. from the interstitial of loose sediments in heavily exposed rockpools in the mediolittoral zone of Tenerife, Canary Islands. The species apparently represents the ultimate apomorphous condition within the genus and co-occurs with Psammogammarus

  20. Chasing the European Dream: Unaccompanied African Youths' Educational Experience in a Canary Islands' Reception Centre and Beyond

    Science.gov (United States)

    Auger-Voyer, Valérie; Montero-Sieburth, Martha; Perez, Lidia Cabrera

    2014-01-01

    In the last two decades, Spain's Canary Islands have received thousands of undocumented migrants arriving by boat from the coasts of North and West Africa. The sharp increase of unaccompanied minors has presented a particular challenge, as these minors fall under the State's protection system and are entitled to an education and other rights, once…

  1. Planck intermediate results XXXVI. Optical identification and redshifts of Planck SZ sources with telescopes at the Canary Islands observatories

    DEFF Research Database (Denmark)

    Ade, P. A. R.; Aghanim, N.; Arnaud, M.;

    2016-01-01

    We present the results of approximately three years of observations of Planck Sunyaev-Zeldovich (SZ) sources with telescopes at the Canary Islands observatories as part of the general optical follow-up programme undertaken by the Planck Collaboration. In total, 78 SZ sources are discussed. Deep-i...

  2. Determinants of organochlorine levels detectable in the amniotic fluid of women from Tenerife Island (Canary Islands, Spain).

    Science.gov (United States)

    Luzardo, Octavio P; Mahtani, Vikesh; Troyano, Juan M; Alvarez de la Rosa, Margarita; Padilla-Pérez, Ana I; Zumbado, Manuel; Almeida, Maira; Burillo-Putze, Guillermo; Boada, Carlos; Boada, Luis D

    2009-07-01

    Organochlorines (OCs) tend to accumulate in human tissues and can be measured in amniotic fluid (AF). The detection of OCs in AF samples reflects intrauterine exposure of human beings to these persistent organic pollutants. The present study was performed to evaluate the level of contamination of AF by OCs in 100 pregnant women from Tenerife Island (Canary Islands, Spain). Gas chromatography/mass spectrometry (GC/MS) was used to identify and quantify the analytes, including 7 polychlorobiphenyl (PCB) congeners and 18 OC pesticides and metabolites. The majority of the AF samples (67%) showed some detectable OC-residue, hexachlorobenzene (HCB) being the most frequently detected compound (66% of the samples) and at the highest concentration (median 0.023 ng/ml). Lindane was also detected in 28% of the samples. Inverse associations were found between previous lactation and hexachlorocyclohexane isomers (HCH) and cyclodienes in the group of younger women (p = 0.037 and p = 0.027, respectively). Unexpectedly, serum values of HCB (r = -0.414; p = 0.04), gamma-HCH (r = -0.294; p = 0.035), and SigmaOCs (r = -0.350; p = 0.014) were negatively related to age. Even more, women with detectable levels of HCH isomers were younger (33.9 +/- 4.9 years) than women with undetectable levels of them (36.1 +/- 4.9 years; p = 0.035). We conclude that approximately one in two fetuses in the Canary Islands is exposed to OCs in utero, and that, therefore, the exposure of young women from these Islands to some HCH isomers persists nowadays. Because prenatal exposure to these chemicals may be a causative factor in adverse health trends, further studies are required to enhance preventive measures.

  3. Study of the thermohygrometric conditions of Juniperus turbinata habitat in the island of El Hierro (Canary Islands)

    Science.gov (United States)

    Salva-Catarineu, Montserrat; Salvador-Franch, Ferran; López-Bustins, Joan Albert; Padrón-Padrón, Perdro A.; Cortés-Lucas, Amparo

    2015-04-01

    The biggest population of Juniperus turbinata throughout the Canary Islands is located in the island of El Hierro. The current extent of juniper woodlands is very small compared with the potential distribution due to heavy exploitation for centuries. Nowadays, the recovery of its natural habitat has such a high environmental and scenic interest since this is a protected species in Europe; however, an improved understanding of the environmental factors that help or limit its recovery is indispensable. Under the JUNITUR project the populations of juniper woodlands in El Hierro are being studied, which are subjected to highly different environments. These environments are mainly determined by their altitude and exposure to NE trade winds. The main objective of this study is to compare the thermohygrometric conditions of three juniper woodlands, located at different altitude and orientation in El Hierro, which present different recovery rates. We are currently using air sensor data loggers fixed to tree branches for recording hourly temperature and humidity data in the three study areas. For this preliminary approach, we analyse daily data of two annual cycles (from September 2012 to August 2014). Our first results show similar thermohygrometric annual cycles among the three study areas. The largest differences are detected in winter temperature and summer humidity between the north (to windward) and south (to leeward) faces of the island. The juniper woodland with a highest recovery rate shows the most extreme temperature conditions in both winter and summer seasons. This last juniper woodland is located leeward to trade winds at 996 m a.s.l. In general terms, the results of this research project might contribute to the knowledge of the juniper bioclimatology in the westernmost of the Canary Islands. Key words: bioclimatology, El Hierro, habitat, Juniperus turbinata, protected species

  4. Oceanic Platform of the Canary Islands: an ocean testbed for ocean energy converters

    Science.gov (United States)

    González, Javier; Hernández-Brito, Joaquín.; Llinás, Octavio

    2010-05-01

    The Oceanic Platform of the Canary Islands (PLOCAN) is a Governmental Consortium aimed to build and operate an off-shore infrastructure to facilitate the deep sea research and speed up the technology associated. This Consortium is overseen by the Spanish Ministry of Science and Innovation and the Canarian Agency for Research and Innovation. The infrastructure consists of an oceanic platform located in an area with depths between 50-100 meters, close to the continental slope and four kilometers off the coast of Gran Canaria, in the archipelago of the Canary Islands. The process of construction will start during the first months of 2010 and is expected to be finished in mid-year 2011. PLOCAN serves five strategic lines: an integral observatory able to explore from the deep ocean to the atmosphere, an ocean technology testbed, a base for underwater vehicles, an innovation platform and a highly specialized training centre. Ocean energy is a suitable source to contribute the limited mix-energy conformed in the archipelago of the Canary Islands with a total population around 2 million people unequally distributed in seven islands. Islands of Gran Canaria and Tenerife support the 80% of the total population with 800.000 people each. PLOCAN will contribute to develop the ocean energy sector establishing a marine testbed allowing prototypes testing at sea under a meticulous monitoring network provided by the integral observatory, generating valuable information to developers. Reducing costs throughout an integral project management is an essential objective to be reach, providing services such as transportation, customs and administrative permits. Ocean surface for testing activities is around 8 km2 with a depth going from 50 to 100 meters, 4km off the coast. Selected areas for testing have off-shore wind power conditions around 500-600 W/m2 and wave power conditions around 6 kW/m in the East coast and 10 kW/m in the North coast. Marine currents in the Canary Islands are

  5. Multivariate Modelling of the Canary Islands Banana Output. The Role of Farmer Income Expectation

    Directory of Open Access Journals (Sweden)

    Concepción González-Concepción

    2008-01-01

    Full Text Available The EU is the world’s largest importer of bananas and the only major managed market in the international banana trade. Spain is the main banana producer within the European Union (EU, followed by France and Portugal. In all these countries the fruit is grown in overseas islands situated in tropical or sub-tropical areas and bananas are a pillar of the economic, social and environmental balance of these regions. Spanish production comes from the Canary Islands, an insular environment located in the Atlantic Ocean more than 1000 km south of the Iberian Peninsula and near the northwest coast of Africa. In the context of high production costs and strong competition from Latin American imports, the compensatory aid that local farmers have been receiving from the EU since 1993 has helped the archipelago to maintain its agricultural position while constituting a main support from an economic, social and landscaping standpoint. This research analyses the Canary Islands banana output evolution through the use of certain multivariate dynamic models that consider the influence of past production costs, past farmer income and future expectations, including a sensitivity analysis. We consider annual data time series on production, perceived prices and production costs for the period 1938-2002. Model predictions are contrasted using data for the period 2003-2006, thus spanning a wide period of time that includes key points such as the 1993 reform and the introduction of the 2006 reform. The empirical work highlights, as do all EU norms, the importance of maintaining adequate farmer income expectations to assure subsistence banana production.

  6. Aquifer Recharge Estimation through Atmospheric Chloride Mass Balance at Las Cañadas Caldera, Tenerife, Canary Islands, Spain

    OpenAIRE

    Rayco Marrero-Diaz; Alcalá, Francisco J.; Pérez, Nemesio M.; Dina L. López; Melián, Gladys V.; Eleazar Padrón; Germán D. Padilla

    2015-01-01

    The atmospheric chloride mass balance (CMB) method was used to estimate net aquifer recharge in Las Cañadas Caldera, an endorheic summit aquifer area about 2000 m a.s.l. with negligible surface runoff, which hosts the largest freshwater reserve in Tenerife Island, Canary Islands, Spain. The wet hydrological year 2005–2006 was selected to compare yearly atmospheric chloride bulk deposition and average chloride content in recharge water just above the water table, both deduced from periodical...

  7. Volcanic hazard assessment for the Canary Islands (Spain) using extreme value theory

    Science.gov (United States)

    Sobradelo, R.; Martí, J.; Mendoza-Rosas, A. T.; Gómez, G.

    2011-10-01

    The Canary Islands are an active volcanic region densely populated and visited by several millions of tourists every year. Nearly twenty eruptions have been reported through written chronicles in the last 600 yr, suggesting that the probability of a new eruption in the near future is far from zero. This shows the importance of assessing and monitoring the volcanic hazard of the region in order to reduce and manage its potential volcanic risk, and ultimately contribute to the design of appropriate preparedness plans. Hence, the probabilistic analysis of the volcanic eruption time series for the Canary Islands is an essential step for the assessment of volcanic hazard and risk in the area. Such a series describes complex processes involving different types of eruptions over different time scales. Here we propose a statistical method for calculating the probabilities of future eruptions which is most appropriate given the nature of the documented historical eruptive data. We first characterize the eruptions by their magnitudes, and then carry out a preliminary analysis of the data to establish the requirements for the statistical method. Past studies in eruptive time series used conventional statistics and treated the series as an homogeneous process. In this paper, we will use a method that accounts for the time-dependence of the series and includes rare or extreme events, in the form of few data of large eruptions, since these data require special methods of analysis. Hence, we will use a statistical method from extreme value theory. In particular, we will apply a non-homogeneous Poisson process to the historical eruptive data of the Canary Islands to estimate the probability of having at least one volcanic event of a magnitude greater than one in the upcoming years. This is done in three steps: First, we analyze the historical eruptive series to assess independence and homogeneity of the process. Second, we perform a Weibull analysis of the distribution of repose

  8. Paleosecular variation of the earth magnetic field at the Canary Islands over the last 15 ka

    Science.gov (United States)

    Kissel, C.; Rodriguez-Gonzalez, A.; Laj, C.; Perez-Torrado, F.; Carracedo, J. C.; Wandres, C.; Guillou, H.

    2015-02-01

    We report on new paleomagnetic directions obtained from 38 lava flows located at Tenerife and Gran Canaria (Canary Islands, Spain). One flow is a historical one (1706 AD) and 28 other flows are dated by radiocarbon between 1550 AD and about 13 200 BC. Nine other flows are not dated but they have stratigraphic links with the other flows. Thermomagnetic curves, unblocking temperatures and coercivities suggest that the main carrier of the remanent magnetization is titanomagnetite with various titanium contents in the pseudo-single domain range. Paleodirections were obtained by thermal and alternating field demagnetization on more than 400 specimens. The two youngest flows yield directions well consistent with the data previously published from the Canary Islands but only covering the last 500 yr. Comparison with model predictions indicates that the models account on the long-term for most of the data. However, on short-term scale, a better agreement is observed with the archeomagnetic-based model predictions (ARCH3K and SHA.DIF.14k). Two time intervals (between 25 BC and 85 AD and around 600-700 BC), however, are characterized by more variable paleomagnetic directions, suggesting that the variability of the earth magnetic field was faster than predicted by the models. On a wider geographical scale, a rather good consistency is observed between the Canarian dataset and those from Northern Africa, Spain and Azores. Field information is well consistent with paleomagnetic information for the undated sites and they both confirm that the eruption rate of the Gran Canaria volcanic system was high around 600 BC, 1000 BC and 4650 BC. Refined ages could be obtained for two of the undated sites using archeomagnetic dating. Combined with the data previously published for the last 500 yr, this new dataset is the first long PSV record available for the Canary Islands, significantly contributing to the archeomagnetic/paleomagnetic database at latitudes lower than 30°N. Improvement

  9. Volcanic hazard assessment for the Canary Islands (Spain using extreme value theory

    Directory of Open Access Journals (Sweden)

    R. Sobradelo

    2011-10-01

    Full Text Available The Canary Islands are an active volcanic region densely populated and visited by several millions of tourists every year. Nearly twenty eruptions have been reported through written chronicles in the last 600 yr, suggesting that the probability of a new eruption in the near future is far from zero. This shows the importance of assessing and monitoring the volcanic hazard of the region in order to reduce and manage its potential volcanic risk, and ultimately contribute to the design of appropriate preparedness plans. Hence, the probabilistic analysis of the volcanic eruption time series for the Canary Islands is an essential step for the assessment of volcanic hazard and risk in the area. Such a series describes complex processes involving different types of eruptions over different time scales. Here we propose a statistical method for calculating the probabilities of future eruptions which is most appropriate given the nature of the documented historical eruptive data. We first characterize the eruptions by their magnitudes, and then carry out a preliminary analysis of the data to establish the requirements for the statistical method. Past studies in eruptive time series used conventional statistics and treated the series as an homogeneous process. In this paper, we will use a method that accounts for the time-dependence of the series and includes rare or extreme events, in the form of few data of large eruptions, since these data require special methods of analysis. Hence, we will use a statistical method from extreme value theory. In particular, we will apply a non-homogeneous Poisson process to the historical eruptive data of the Canary Islands to estimate the probability of having at least one volcanic event of a magnitude greater than one in the upcoming years. This is done in three steps: First, we analyze the historical eruptive series to assess independence and homogeneity of the process. Second, we perform a Weibull analysis of the

  10. Distribution and genetic variation of hymenolepidid cestodes in murid rodents on the Canary Islands (Spain

    Directory of Open Access Journals (Sweden)

    Feliu Carlos

    2011-09-01

    Full Text Available Abstract Background In the Canary Islands there are no previous data about tapeworms (Cestoda of rodents. In order to identify the hymenolepidid species present in these hosts, a survey of 1,017 murine (349 Rattus rattus, 13 Rattus norvegicus and 655 Mus musculus domesticus was carried out in the whole Archipelago. Molecular studies based on nuclear ITS1 and mitochondrial COI loci were performed to confirm the identifications and to analyse the levels of genetic variation and differentiation. Results Three species of hymenolepidids were identified: Hymenolepis diminuta, Rodentolepis microstoma and Rodentolepis fraterna. Hymenolepis diminuta (in rats and R. microstoma (in mice showed a widespread distribution in the Archipelago, and R. fraterna was the least spread species, appearing only on five of the islands. The hymenolepidids found on Fuerteventura, Lanzarote and La Graciosa were restricted to one area. The COI network of H. diminuta showed that the haplotypes from Lanzarote and Fuerteventura are the most distant with respect to the other islands, but clearly related among them. Conclusions Founder effects and biotic and abiotic factors could have played important role in the presence/absence of the hymenolepidid species in determined locations. The haplotypes from the eastern islands (Fuerteventura and Lanzarote seem to have shared an ancestral haplotype very distant from the most frequent one that was found in the rest of the islands. Two colonization events or a single event with subsequent isolation and reduced gene flow between western-central and eastern islands, have taken place in the Archipelago. The three tapeworms detected are zoonotic species, and their presence among rodents from this Archipelago suggests a potential health risk to human via environmental contamination in high risk areas. However, the relatively low prevalence of infestations detected and the focal distribution of some of these species on certain islands reduce

  11. Early Pliocene fishes (Chondrichthyes, Osteichthyes from Gran Canaria and Fuerteventura (Canary Islands, Spain

    Directory of Open Access Journals (Sweden)

    J. F. Betancort

    2016-11-01

    Full Text Available Fossil fish teeth are contained in marine deposits dated at ca 4.8 Ma found on the islands of Gran Canaria and Fuerteventura (Canary Islands, Spain. These islands, situated in the North Atlantic Subtropical Gyre, can be considered a mid-way stopover point between the Caribbean Sea, with the Central American Seaway about to close in this epoch, and the Mediterranean, in the first stage of its post-Messinian Gibraltar Seaway period. Accordingly, there existed extensive pantropical communication, particularly for nektonic animals capable of travelling large distances. In this paper, we present a number of fossil fishes, most of which are identified for the first time on the basis of their teeth: the Chondrichthyes species Carcharocles megalodon, Parotodus benedeni, Cosmopolitodus hastalis, Isurus oxyrinchus, Carcharias cf. acutissima, Carcharhinus cf. leucas, Carcharhinus cf. priscus, Galeocerdo cf. aduncus, and the Osteichthyes species Archosargus cinctus, Labrodon pavimentatum, and Diodon scillae. Coincidences are observed between these ichthyofauna and specimens found in the Azores Islands, the Pacific coast of America and the Mediterranean Sea.

  12. Sex determination by discriminant function analysis of the right tibia in the prehispanic population of the Canary Islands.

    Science.gov (United States)

    González-Reimers, E; Velasco-Vázquez, J; Arnay-de-la-Rosa, M; Santolaria-Fernández, F

    2000-02-28

    This study has been performed in order to define standards usable to determine the sex of prehispanic individuals from the Canary Islands from their skeletal remains. Osteometric information at the right tibia was obtained from 59 complete skeletons from Gran Canaria, housed in the Museo Canario (Las Palmas), 45 males and 14 females (this constitutes the totality of complete prehispanic skeletons known from Gran Canaria). The parameters measured were: tibial length, proximal and distal epiphyseal breadth, transverse and anteroposterior diameter, perimeter at the nutrition foramen levels and minimum shaft perimeter. These parameters were subjected to different SPSS discriminant function analysis, combining all of them, or only the proximal or distal ones, without tibial length, etc., in order to obtain functions usable even if only bone fragments are available. Transverse diameter, proximal epiphyseal breadth and minimum shaft perimeter showed the highest discriminant power. The functions obtained showed high average accuracies, ranging from 94.9 to 98.3%, with female accuracies of 100%. The functions obtained were further applied to a test prehispanic population (ten males and ten females) from El Hierro. Overall accuracies of the functions when applied to this population ranged from 65 to 94.7%, with female accuracies ranging 80% to 100%.

  13. Evaluation of Acanthamoeba isolates from environmental sources in Tenerife, Canary Islands, Spain.

    Science.gov (United States)

    Lorenzo-Morales, Jacob; Monteverde-Miranda, Carlos A; Jiménez, Concepción; Tejedor, María Luisa; Valladares, Basilio; Ortega-Rivas, Antonio

    2005-01-01

    Tests for potentially pathogenic amoebae were carried out in order to determine the presence of free-living amoebae of genus Acanthamoeba in soil and beach sand sources related to human environments in Tenerife, Canary Islands, Spain. Acanthamoeba identification was based on the morphology of cyst and trophozoite forms and PCR amplification with a genus specific primer pair. The pathogenical potential of Acanthamoeba isolates was characterized by temperature and osmotolerance assays and PCR reactions with two primer pairs related to Acanthamoeba pathogenesis. The results demonstrate the presence of potential pathogenic strain in both sources. Thus, some of the amoebae found in these habitats could act as opportunistic pathogens and may present a risk to human health.

  14. Isolation and identification of pathogenic Acanthamoeba strains in Tenerife, Canary Islands, Spain from water sources.

    Science.gov (United States)

    Lorenzo-Morales, Jacob; Ortega-Rivas, Antonio; Foronda, Pilar; Martínez, Enrique; Valladares, Basilio

    2005-03-01

    A comprehensive survey to document the presence of free-living amoebae of the genus Acanthamoeba was conducted in tap water and sea water sources related to human environments in Tenerife, Canary Islands, Spain. Acanthamoeba identification was based on the morphology of cyst and trophozoite forms and PCR amplification with a genus-specific primer pair. The pathogenic potential of Acanthamoeba isolates was characterized by temperature and osmotolerance assays and PCR reactions with two primer pairs related to Acanthamoeba pathogenesis. The results demonstrate the presence of potentially pathogenic strains in both sources. Thus, some of the amoebae in these aquatic habitats can act as opportunistic pathogens, could play a role in the diseases of aquatic organisms, and may present a risk to human health.

  15. Content of free phenolic compounds in cultivars of potatoes harvested in Tenerife (Canary Islands).

    Science.gov (United States)

    Verde Méndez, Candelaria del Mar; Rodríguez Delgado, Miguel Angel; Rodríguez Rodríguez, Elena María; Díaz Romero, Carlos

    2004-03-10

    Determination of free phenolic compounds in potato samples was optimized using a high-performance liquid chromatographic (HPLC) method with on-line diode array detection. This method was applied to samples of four cultivars of potatoes harvested in Tenerife (Canary Islands). The free phenolic compounds found in the potato samples were (+)-catechin, chlorogenic acid, caffeic acid, p-coumaric acid, and ferulic acid. Potato samples belonging to Colorada cultivar, ssp. andigena, had mean concentrations of total phenolic compounds and chlorogenic acid higher than those found for Kerr's Pink and Cara cultivars, ssp. tuberosum, and for Negra cultivar, S. x chaucha. In contrast, p-coumaric acid was not detected in any potato samples of the Colorada cultivar. Traditional potatoes presented a higher mean concentration of ferulic acid than recently imported potatoes. A significant and negative correlation was established between (+)-catechin and p-coumaric acid. A considerable contribution to the daily intake of flavonoids was observed with the actual consumption of potatoes.

  16. The necessity of reconceptualizing the migration of unaccompanied minors to the Canary Islands of Spain

    Directory of Open Access Journals (Sweden)

    Esther Torrado Martín-Palomino

    2015-07-01

    Full Text Available The migration of unaccompanied foreign minors (menores extranjeros no acompañados, MENA represents a new model for international mobility in Spain, one with its own particularities compared with other migratory flows. The dual nature of being unaccompanied and unauthorized leads to conflicts in the care and integration of these new migrants. However, this dual nature is one of the main prerequisites for the development of this mobility model (but not the only one and for developing strategies specific to this group. The Canary Islands, because of their position on the southern intercontinental border and their insularity, offer particular models of individual migration flows of primarily highly vulnerable African children and a close relationship with human smuggling and trafficking networks.

  17. Water dynamics in a laurel montane cloud forest in the Garajonay National Park (Canary Islands, Spain

    Directory of Open Access Journals (Sweden)

    G. García-Santos

    2004-01-01

    Full Text Available Field measurements from February 2003 to January 2004 in a humid (but dry in summer crest heath wood-land (degraded laurel forest in the National Park of Garajonay, Canary Islands (Spain, were combined to calculate water balance components. The water balance domain is at the surface of the catchment and is controlled by atmospheric processes and vegetation. This study found that annual water income (rainfall plus fog water was 1440 mm year-1, half of which was occult (or fog precipitation, while stand transpiration estimated from measurements of sap flow amounted, annually, to 40% of potential evapotranspiration calculated from measurements of meteorological variables. The positive role of crest laurel forests, which transpire less water than is incoming from rain and fog is emphasised. Keywords: laurel forest, fog interception, stand transpiration, sap flow, hydrological cycle

  18. Reproductive pattern of Pterocladiella capillacea (Gelidiales, Rhodophyta) at Canary Islands (Spain, Atlantic Ocean)

    Institute of Scientific and Technical Information of China (English)

    Mascha Stroobant; Milena Polifrone

    2014-01-01

    Objective: To record the reproductive pattern of a natural population of Pterocladiella capillacea from Gáldar (Canary Islands, Spain) from February to August in relation to temperature, irradiance and photoperiod environmental conditions.Methods:Field observation of reproductive thalli was used at different seasons in the year. Results: Tetrasporophytes and vegetative thalli were observed during all the period of study, while female gametophytes bearing cystocarps have been found from May to August in correspondence with the highest water temperature and irradiance values.Conclusions:Our data suggest that the temperature may be the determining factor which regulates the presence of tetrasporophytes in the field. The constant presence of tetrasporophytes could depend on the low excursion range of water temperature (4-5 °C) throughout the period of study, with the highest abundance in February at 20 °C.

  19. Composition of air masses in Fuerteventura (Canary Islands) according to their origins

    Energy Technology Data Exchange (ETDEWEB)

    Patier, R.F.; Diez Hernandez, P.; Diaz Ramiro, E.; Ballesteros, J.S.; Santos-Alves, S.G. dos [Centro Nacional de Sanidad Ambiental, Madrid (Spain). Inst. de Salud Carlos III

    1994-12-31

    The Centro Nacional de Sanidad Ambiental has among their duties the background atmospheric pollution monitoring in Spain. To do so, the laboratory has set up 6 field stations in the Iberian Peninsula. In these stations, both gaseous and particulate pollutants are currently analyzed. However, there is a lack of data about the atmospheric pollution in the Canary, where they are a very strong influence of natural emissions from sea and the Saharan desert, mixed with anthropogenic ones. Therefore, during the ASTEX/MAGE project the CNSA established a station in Fuerteventura island, characterized by the nonexistence of man-made emissions, to measure some atmospheric pollutants, in order to foresee their origins. In this study, the authors analyzed some pollutants that are used to obtain a clue about the sources of air masses such as gaseous ozone and metallic compounds (vanadium, iron and manganese) in the atmospheric aerosol fractionated by size.

  20. Holocene geomagnetic field intensity variations: Contribution from the low latitude Canary Islands site

    Science.gov (United States)

    Kissel, C.; Laj, C.; Rodriguez-Gonzalez, A.; Perez-Torrado, F.; Carracedo, J. C.; Wandres, C.

    2015-11-01

    New absolute paleomagnetic intensity (PI) are investigated from 37 lava flows located at Tenerife and Gran Canaria (Canary Islands). They complete previously published directional results from the same flows and therefore allow to examine the time variations of the full geomagnetic vector. Twenty-eight flows are radiocarbon dated between 1706 AD and about 13 200 BC and one is historical. Eight other flows are not dated but they have stratigraphic links with the dated flows and archeomagnetic ages had been attributed to them based on their paleomagnetic directions. Various mineralogical analyses were conducted, giving access to the nature of the magnetic minerals and to their grain size. We performed the original Thellier and Thellier paleointensity (PI) experiments with a success rate of about 65% coupling this experiment with the strict set of selection criteria PICRIT-03. The mean PIs at the flow level are based on 3 to 12 independent PI determinations except for one site in which only one reliable determination could be obtained. The data indicate some variability in the local field intensity with a prominent PI peak centered around 600 BC and reaching 80 μT (VADM 16 ×1022 Am2), documented for the first time in this region. Combined with the published data obtained from western Africa, Spain, Portugal, Morocco and the Azores within a 2000 km-radius around the Canary Islands, our data allow to construct a curve illustrating the Earth magnetic field intensity fluctuations for Southwestern Europe/Western Africa. This curve, compared to the one produced for the Middle East and one calculated for Central Asia shows that maximum intensity patches have a very large geographical extent. They do not yet appear clearly in the models of variations of the dipolar field intensity.

  1. Vertical distribution, composition and migratory patterns of acoustic scattering layers in the Canary Islands

    Science.gov (United States)

    Ariza, A.; Landeira, J. M.; Escánez, A.; Wienerroither, R.; Aguilar de Soto, N.; Røstad, A.; Kaartvedt, S.; Hernández-León, S.

    2016-05-01

    Diel vertical migration (DVM) facilitates biogeochemical exchanges between shallow waters and the deep ocean. An effective way of monitoring the migrant biota is by acoustic observations although the interpretation of the scattering layers poses challenges. Here we combine results from acoustic observations at 18 and 38 kHz with limited net sampling in order to unveil the origin of acoustic phenomena around the Canary Islands, subtropical northeast Atlantic Ocean. Trawling data revealed a high diversity of fishes, decapods and cephalopods (152 species), although few dominant species likely were responsible for most of the sound scattering in the region. We identified four different acoustic scattering layers in the mesopelagic realm: (1) at 400-500 m depth, a swimbladder resonance phenomenon at 18 kHz produced by gas-bearing migrant fish such as Vinciguerria spp. and Lobianchia dofleini, (2) at 500-600 m depth, a dense 38 kHz layer resulting primarily from the gas-bearing and non-migrant fish Cyclothone braueri, and to a lesser extent, from fluid-like migrant fauna also inhabiting these depths, (3) between 600 and 800 m depth, a weak signal at both 18 and 38 kHz ascribed either to migrant fish or decapods, and (4) below 800 m depth, a weak non-migrant layer at 18 kHz which was not sampled. All the dielly migrating layers reached the epipelagic zone at night, with the shorter-range migrations moving at 4.6 ± 2.6 cm s - 1 and the long-range ones at 11.5 ± 3.8 cm s - 1. This work reduces uncertainties interpreting standard frequencies in mesopelagic studies, while enhances the potential of acoustics for future research and monitoring of the deep pelagic fauna in the Canary Islands.

  2. Vertical distribution, composition and migratory patterns of acoustic scattering layers in the Canary Islands

    KAUST Repository

    Ariza, A.

    2016-01-21

    Diel vertical migration (DVM) facilitates biogeochemical exchanges between shallow waters and the deep ocean. An effective way of monitoring the migrant biota is by acoustic observations although the interpretation of the scattering layers poses challenges. Here we combine results from acoustic observations at 18 and 38 kHz with limited net sampling in order to unveil the origin of acoustic phenomena around the Canary Islands, subtropical northeast Atlantic Ocean. Trawling data revealed a high diversity of fishes, decapods and cephalopods (152 species), although few dominant species likely were responsible for most of the sound scattering in the region. We identified four different acoustic scattering layers in the mesopelagic realm: (1) at 400–500 m depth, a swimbladder resonance phenomenon at 18 kHz produced by gas-bearing migrant fish such as Vinciguerria spp. and Lobianchia dofleini, (2) at 500–600 m depth, a dense 38 kHz layer resulting primarily from the gas-bearing and non-migrant fish Cyclothone braueri, and to a lesser extent, from fluid-like migrant fauna also inhabiting these depths, (3) between 600 and 800 m depth, a weak signal at both 18 and 38 kHz ascribed either to migrant fish or decapods, and (4) below 800 m depth, a weak non-migrant layer at 18 kHz which was not sampled. All the dielly migrating layers reached the epipelagic zone at night, with the shorter-range migrations moving at 4.6 ± 2.6 cm s − 1 and the long-range ones at 11.5 ± 3.8 cm s − 1. This work reduces uncertainties interpreting standard frequencies in mesopelagic studies, while enhances the potential of acoustics for future research and monitoring of the deep pelagic fauna in the Canary Islands.

  3. Heavy and trace metal concentrations in three rockpool shrimp species (Palaemon elegans, Palaemon adspersus and Palaemon serratus) from Tenerife (Canary Islands).

    Science.gov (United States)

    Lozano, Gonzalo; Herraiz, Elena; Hardisson, Arturo; Gutiérrez, Angel J; González-Weller, Dailos; Rubio, Carmen

    2010-09-01

    Trace metal concentrations (Fe, Cu, Co, Zn, Ni and V) were investigated in three rockpool shrimp species (Palaemon elegans, Palaemon adspersus and Palaemon serratus) from six littoral sampling sites (polluted and non-polluted) of Tenerife in the Canary Islands (Central Eastern Atlantic), Spain. Sex ratio for all three species has been determined: females predominate over males in all species and significant differences in total length and cephalothorax length was detected between sexes, being females larger than males. By other side, concentrations of trace metals were determined in whole specimens. Higher mean values for every metal were observed in P. adspersus. In males, higher values were observed in P. elegans and P. serratus, whereas in P. adspersus, mean values are higher in females. Finally, mean concentrations of trace metals studied were higher, in general terms, in the two clearly polluted stations: Santa Cruz of Tenerife commercial harbour and its fishery dock dependency.

  4. Parasitic helminths of the wild rabbit, Oryctolagus cuniculus, in different bioclimatic zones in Tenerife, Canary Islands.

    Science.gov (United States)

    Foronda, P; Del Castillo, A; Abreu, N; Figueruelo, E; Piñero, J; Casanova, J C

    2003-12-01

    Faunistic and ecological analyses of the wild rabbit helminth fauna were undertaken in Tenerife island (Canary Islands). Rabbits were collected between 1998 and 2000 in seven bioclimatic zones in Tenerife selected by orientation and altitude. Five parasite species were identified, three cestodes (Taenia pisiformis (larvae), Andrya cuniculi and Mosgovoyia ctenoides) and two nematodes (Trichostrongylus retortaeformis and Passalurus ambiguus). Taenia pisiformis presented an irregular distribution with significant differences in prevalences between the zones. Andrya cuniculi was only found in two zones and there were no significant differences in prevalence values. Mosgovoyia ctenoides presented a wide distribution with significant prevalences, which were higher in northern compared to southern zones. Trichostrongylus retortaeformis was absent in the low southern zones of the island. Passalurus ambiguus was found in all zones with no significant difference in the prevalence of infection. The differences in prevalences are likely to be explained by abiotic factors in the case of T. retortaeformis, and by the absence of definitive and intermediate hosts in the case of T. pisiformis and A. cuniculi, respectively. All parasite species in Tenerife are common helminths in the Iberian Peninsula, from which their rabbit hosts originated. No significant differences were recorded in the mean intensities of infection of any of the parasite species identified.

  5. Agrotourism, sustainable tourism and Ultraperipheral areas: The Case of Canary Islands

    Directory of Open Access Journals (Sweden)

    Parra López, Eduardo

    2006-01-01

    Full Text Available Ultraperipheral regions share certain common characteristics, such as their remoteness from the major supplying centres, their scanty resources, their island status or isolated location and consequent fragmentation of markets. Over the past decades, there has been an increasing awareness of the impact of ultraperiphericity on the development of a number of regions and islands. The concept of “ultraperiphericity” includes specific geographic circumstances that influence the development and specialisation of economies, competitiveness and business strategies. Agrotourism is playing an ever increasingly important role in the diversification of the agriculture, farming and tourism sectors into the Ultraperipheral Regions. Therefore, particular attention should be paid to the economic development of rural areas in Ultraperipheral Areas and to the reappraisal of agriculture, which is closely connected with tourism. Agrotourism is essential to diversify, transform and improve the competitiveness and quality of farms. This paper examines the impact of Agrotourism as an alternative to sun and sand tourism, resulting in the growth of family income, in rural development and, in short, in new approaches to the tourism industry. A further goal of the paper is to develop a strategic analysis of Agrotourism, studying both supply and demand in the Canary Islands

  6. Coupled paleomagnetic/dating investigation of the Upper Jaramillo reversal from lava sequences (Tenerife, Canary islands)

    Science.gov (United States)

    Laj, Carlo; Kissel, Catherine; Guillou, Herve; Carracedo, Juan-Carlos; Perez-Torrado, Francisco; Rodriguez-Gonzalez, Alejandro; Wandres, Camille; Nomade, Sebastien

    2013-04-01

    A sequence of lava flows has been emplaced during the transition between the Jaramillo subchron and the Matuyama chron in Tenerife (Canary island). This sequence is located along the flank of the collapse of Güimar, in the south central part of the island. It includes 26 flows from the full normal polarity to the full reverse polarity. On the basis of K/Ar dating, the section is bracketed between 1012 ± 18 ka and 975 ± 17 ka. Additional coupled K/Ar and 40Ar/39Ar dating have been obtained through the sequence and place the reversal itself between 992 ± 12 ka and 979 ± 10 ka consistently with previous dating of the upper Jaramillo reversal. They indicate a particularly high extrusion rate at this site (Guillou et al., session IG9/GMPV7/PS9.6). Full paleomagnetic analyses have been conducted on these lava flows including rock magnetic analyses (thermomagnetic curves, hysteresis curves, FORC diagrams, k-T curves), zero-field stepwise thermal and alternating field demagnetizations. Thellier and Thellier paleointensity (PI) determinations were also performed and based on the selection criteria defined by Kissel and Laj (2004), only 30% of the samples yielded reliable results. The first 9 flows at the bottom of the sequence are characterized by a normal polarity. Only two of them yield PI consistent with the present day field intensity in the Canary islands. The two following flows are deviated from the magnetic pole, beyond the secular variation but their VGP is still in the northern hemisphere, over northeastern Pacific. The associated intensity drops significantly to about 11 µT that is less than 30% of the present dipole value. The following flows have all a negative inclination and their PI remain low (around 8-12 µT). The virtual geomagnetic poles are first over East Antarctica before describing a northward loop almost up to New Zealand. The VGPs then go back close to the southern pole, and mark a second loop to southeastern Pacific associated with little

  7. Phylogeography of the endangered darkling beetle species of Pimelia endemic to Gran Canaria (Canary Islands).

    Science.gov (United States)

    Contreras-Días, Hermans G; Moya, Oscar; Oromí, Pedro; Juan, Carlos

    2003-08-01

    Phylogenetic and geographical nested clade analysis (NCA) methods were applied to mitochondrial DNA sequences of Pimelia darkling beetles (Coleoptera, Tenebrionidae) endemic to Gran Canaria, an island in the Canary archipelago. The three species P. granulicollis, P. estevezi and P. sparsa occur on the island, the latter with three recognized subspecies. Another species, P. fernandezlopezi (endemic to the island of La Gomera) is a close relative of P. granulicollis based on partial Cytochrome Oxidase I mtDNA sequences obtained in a previous study. Some of these beetles are endangered, so phylogeographical structure within species and populations can help to define conservation priorities. A total of about 700 bp of Cytochrome Oxidase II were examined in 18 populations and up to 75 individuals excluding outgroups. Among them, 22 haplotypes were exclusive to P. granulicollis and P. estevezi and 31 were from P. sparsa. Phylogenetic analysis points to the paraphyly of Gran Canarian Pimelia, as the La Gomera P. fernandezlopezi haplotypes are included in them, and reciprocal monophyly of two species groups: one constituted by P. granulicollis, P. estevezi and P. fernandezlopezi (subgenus Aphanaspis), and the other by P. sparsa'sensu lato'. The two species groups show a remarkably high mtDNA divergence. Within P. sparsa, different analyses all reveal a common result, i.e. conflict between current subspecific taxonomic designations and evolutionary units, while P. estevezi and P. fernandezlopezi are very close to P. granulicollis measured at the mtDNA level. Geographical NCA identifies several cases of nonrandom associations between haplotypes and geography that may be caused by allopatric fragmentation of populations with some cases of restriction of gene flow or range expansion. Analyses of molecular variance and geographical NCA allow definition of evolutionary units for conservation purposes in both species-groups and suggest scenarios in which vicariance caused by

  8. Comments on Uncertainty in Groundwater Governance in the Volcanic Canary Islands, Spain

    Directory of Open Access Journals (Sweden)

    Emilio Custodio

    2015-06-01

    Full Text Available The uncertainty associated with natural magnitudes and processes is conspicuous in water resources and groundwater evaluation. This uncertainty has an essential component and a part that can be reduced to some extent by increasing knowledge, improving monitoring coverage, continuous elaboration of data and accuracy and addressing the related economic and social aspects involved. Reducing uncertainty has a cost that may not be justified by the improvement that is obtainable, but that has to be known to make the right decisions. With this idea, this paper contributes general comments on the evaluation of groundwater resources in the semiarid Canary Islands and on some of the main sources of uncertainty, but a full treatment is not attempted, nor how to reduce it. Although the point of view is local, these comments may help to address similar situations on other islands where similar problems appear. A consequence of physical and hydrological uncertainty is that different hydrogeological and water resource studies and evaluations may yield different results. Understanding and coarsely evaluating uncertainty helps in reducing administrative instability, poor decisions that may harm groundwater property rights, the rise of complaints and the sub-optimal use of the scarce water resources available in semiarid areas. Transparency and honesty are needed, but especially a clear understanding of what numbers mean and the uncertainty around them, to act soundly and avoid conflicting and damaging rigid attitudes. However, the different situations could condition that what may be good in a place, may not always be the case in other places.

  9. Palaeomagnetic constraints on the age of Lomo Negro volcanic eruption (El Hierro, Canary Islands)

    Science.gov (United States)

    Villasante-Marcos, Víctor; Pavón-Carrasco, Francisco Javier

    2014-12-01

    A palaeomagnetic study has been carried out in 29 cores drilled at six different sites from the volcanic products of Lomo Negro eruption (El Hierro, Canary Islands, Spain). Systematic thermal and alternating field demagnetization of the samples' natural remanent magnetization revealed a northward, stable palaeomagnetic direction similar in all the samples. Rock magnetic experiments indicate that this palaeomagnetic component is carried by a mixture of high-Ti and low-Ti titanomagnetite crystals typical of basaltic lithologies that have experienced a significant degree of oxyexsolution during subaerial cooling. The well constrained palaeomagnetic direction of Lomo Negro lavas was used to perform a palaeomagnetic dating of the volcanic event, using the SHA.DIF.14k global geomagnetic model restricted for the last 3000 yr. It can be unambiguously concluded that Lomo Negro eruption occurred well before the previously proposed date of 1793 AD, with three different age ranges being statistically possible during the last 3 ka: 115 BC-7 AD, 410-626 AD and 1499-1602 AD. The calibration of a previously published non-calibrated 14C dating suggests a XVI c. date for Lomo Negro eruption. This conclusion leaves open the possibility that the seismic crisis occurred at El Hierro in 1793 AD was related to an intrusive magmatic event that either did not reach the surface or either culminated in an unregistered submarine eruption similar to the one occurred in 2011-2012 at the southern off-shore ridge of the island.

  10. Tools for sustainability assessment in island socio-ecological systems: an application to the Canary Islands

    Directory of Open Access Journals (Sweden)

    Isabel Banos-González

    2016-05-01

    Full Text Available An integral dynamic model, in combination with other methods (indicators, policy and scenario analysis, is presented as a tool for sustainability assessment in island socio-ecological systems (SES. The Fuerteventura sustainability model (FSM, tested for the 1996-2011, allows a better understanding of the dynamic interactions between sustainability indicators and other factors of this island. The FSM was first applied to analyse the vulnerability of this island to climate change for the 2012-2025 period; results point to the need for urgent measures to mitigate its effects on some of the analysed indicators. A set of policy measures was then assessed from the behaviour of nine indicators and their sustainability thresholds. Finally, the FSM facilitated the development of a dynamic model of the island of El Hierro, extrapolating the features common to both SES. We propose this to be a useful tool for the quantitative sustainability assessment and the management of real island socio-ecological systems

  11. Holocene geomagnetic field variations from low latitude site: contribution from the Canary Islands

    Science.gov (United States)

    Kissel, Catherine; Laj, Carlo; Rodriguez-Gonzalez, Alejandro; Perez-Torrado, Francisco; Carrracedo, Juan-Carlos; Wandres, Camille

    2016-04-01

    Full geomagnetic vector information was retrieved from 37 lava flows (corresponding to 38 sites because one flow was sampled at two different localities) located in Tenerife and Gran Canaria (Canary Islands). Twenty-eight flows are dated between 1706 AD and about 13200 BC and one is historical. Eight other non-dated flows have stratigraphic links with the dated flows and at the end, our study allowed us to attribute to them archeomagnetic ages based on their paleomagnetic characteristics. Various mineralogical analyses were conducted, giving access to the nature and grain size of the magnetic minerals. Full stepwise (about 13 steps) thermal and AF demagnetizations were conducted on more than 400 samples to determine the paleomagnetic directions. The individual MAD values are on the average about 2° and the mean precision parameter at the flow scale (alpha95) is 4.2°. For paleointensities (PI), we performed the original Thellier and Thellier experiments with a success rate of about 65%, coupling it with the strict set of selection criteria PICRIT-03. The mean PIs at the flow level are based on 3 to 12 independent PI determinations except for one site in which only one reliable determination could be obtained. The obtained data are unique in this area over the 1000-14000 BC period and they are complementary to the dataset obtained in the Canary Islands for the last 500 years. Over the last 3 kyr, they indicate some variability in the local field intensity with a prominent PI peak centered around 600 BC and reaching 80 μT (VADM 16 x 10 ^22 Am ^2), documented by four different flows and associated to significantly easterly deviated declinations. The directional data are rather consistent with the most recent models proposed for that area but the obtained PI indicate that models largely underestimate the paleointensities. Combined with published data obtained from western Africa, Spain, Portugal, Morocco and the Azores within a 2000 km-radius around the Canary

  12. Processing of radon time series in underground environments: Implications for volcanic surveillance in the island of Tenerife, Canary Islands, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Vinas, Ronaldo [Department of Soil Sciences and Geology, Faculty of Biology, Universidad de La Laguna, Av. Astrofisico Fransicso Sanchez s/n, 38206 Tenerife (Spain); Eff-Darwich, Antonio [Department of Soil Sciences and Geology, Faculty of Biology, Universidad de La Laguna, Av. Astrofisico Fransicso Sanchez s/n, 38206 Tenerife (Spain)]. E-mail: adarwich@ull.es; Soler, Vicente [Volcanological Station of the Canary Islands, IPNA-CSIC, 38206 La Laguna, Tenerife (Spain); Martin-Luis, Maria C. [Department of Soil Sciences and Geology, Faculty of Biology, Universidad de La Laguna, Av. Astrofisico Fransicso Sanchez s/n, 38206 Tenerife (Spain); Quesada, Maria L. [Department of Soil Sciences and Geology, Faculty of Biology, Universidad de La Laguna, Av. Astrofisico Fransicso Sanchez s/n, 38206 Tenerife (Spain); Nuez, Julio de la [Department of Soil Sciences and Geology, Faculty of Biology, Universidad de La Laguna, Av. Astrofisico Fransicso Sanchez s/n, 38206 Tenerife (Spain)

    2007-01-15

    The analysis of temporal and spatial variations in the flux of soil gases across the soil-air interface is a useful tool to study geo-dynamical processes associated with volcanic and/or seismic activity. However, many of these variations are induced by external variables, such as temperature, barometric pressure, rainfall and other meteorological variables. In an attempt to filter out non-endogenous variations in the emissions of gases, the optimal choice of the monitoring sites with numerical filtering techniques based on multi-variate and frequency domain analysis of the time series for gaseous emissions were combined, in the case of radon ({sup 222}Rn). Monitoring sites are located in underground galleries in the volcanic island of Tenerife, Canary Islands, Spain. Since the effect of wind, rainfall and temperature variations are very small inside galleries, a first natural filtering process of external parameters in the emissions of gases was achieved. This new approach has been successfully tested and as a result, the background level for radon emissions at various locations has been defined, by which correlations between gaseous emissions and the volcanic and/or seismic activity could be carried out.

  13. Introduction of non-native marine fish species to the Canary Islands waters through oil platforms as vectors

    Science.gov (United States)

    Pajuelo, José G.; González, José A.; Triay-Portella, Raül; Martín, José A.; Ruiz-Díaz, Raquel; Lorenzo, José M.; Luque, Ángel

    2016-11-01

    This work documents the introduction of non-native fish species to the Canary Islands (central-eastern Atlantic) through oil rigs. Methodological approaches have included surveys by underwater visual censuses around and under oil platforms and along the docking area of rigs at the Port of Las Palmas. Eleven non-native fish species were registered. Paranthias furcifer, Abudefduf hoefleri, Acanthurus bahianus, Acanthurus chirurgus, and Acanthurus coeruleus are first recorded from the Canaries herein. Other three species could not be identified, although they have never been observed in the Canaries. Cephalopholis taeniops, Abudefduf saxatilis, and Acanthurus monroviae had been previously recorded. Native areas of these species coincide with the areas of origin and the scale of oil rigs with destination the Port of Las Palmas. The absence of native species in the censuses at rigs and their presence at rigs docking area, together with the observation of non-native species after the departure of platforms, reject the possibility that these non-native species were already present in the area introduced by another vector. C. taeniops, A. hoefleri, A. saxatilis, A. chirurgus, A. coeruleus and A. monroviae are clearly seafarer species. A. bahianus seems to be a potential seafarer species. P. furcifer is a castaway species. For the moment, the number of individuals of the non-native species in marine ecosystems of the Canaries seems to be low, and more investigation is needed for controlling these translocations.

  14. Monitoring serum PCB levels in the adult population of the Canary Islands (Spain

    Directory of Open Access Journals (Sweden)

    Guillermo Burillo-Putze

    2015-07-01

    Full Text Available Polychlorinated biphenyls (PCBs are persistent organic chemicals that have been detected in human serum or tissues all over the world. These pollutants could exert a number of deleterious effects on humans and wildlife, including carcinogenic processes. The Spanish population of the Canary Islands was evaluated with respect to PCB levels more than ten years ago showing lower levels than other Western populations. The objective of our study was to assess the current level of contamination by PCBs showed by this population. We measured serum PCBs in a sample of healthy adult subjects (206 serum samples from subjects with an average age of 66 years old to evaluate the potential modification of PCB serum levels in this population during the last decade. PCB congeners (28, 52, 77, 81, 101, 105, 114, 118, 123, 126, 138, 153, 156, 157, 167, 169, 180, and 189 were measured by gas chromatography-mass spectrometry (GC/MS. Our results showed that PCB residues were found in 84% of serum samples analyzed, the congeners 28, 153 and 180 being the most frequently detected and at the highest median values (0.1 ng/mL. In addition, the median concentration of the sum of those PCBs considered as markers of environmental contamination by these chemicals (Marker-PCBs was 0.6 ng/mL, reaching values as high as as 2.6 ng/mL in the 95th percentile. Levels of the sum of PCBs with toxic effects similar to dioxins (dioxin-like PCBs reached median values of 0.4 ng/mL in the 95th percentile. The reported levels are similar to those described previously in this population more than ten years ago, in the sense that the inhabitants of the Canary Archipelago show levels of PCB contamination lower than the majority of populations from developed countries. These findings suggest that currently there is not any active source of these chemicals in this archipelago. Nevertheless, as foods seem to be a relevant source for these compounds, Public Health authorities should monitor the

  15. Carbon dioxide and helium dissolved gases in groundwater at central Tenerife Island, Canary Islands: chemical and isotopic characterization

    Science.gov (United States)

    Marrero-Diaz, Rayco; López, Dina; Perez, Nemesio M.; Custodio, Emilio; Sumino, Hirochika; Melián, Gladys V.; Padrón, Eleazar; Hernandez, Pedro A.; Calvo, David; Barrancos, José; Padilla, Germán; Sortino, Francesco

    2015-10-01

    Seismic-volcanic unrest was detected between 2004 and 2005 in the central and northwest zones of Tenerife Island (Canary Islands, Spain). With the aim of strengthening the program of geochemical and seismic-volcanic surveillance, a study of the origin, characteristics, and spatial distribution of dissolved carbon dioxide (CO2) and helium (He) gases in the volcanic aquifer of central Tenerife Island and around Teide volcano was carried out. This work also improves the hydrogeological and hydrogeochemical conceptual model of groundwater flow. Dissolved CO2 concentrations in sampled groundwater are several orders of magnitude higher than that of air-saturated water (ASW) suggesting a significant contribution of non-atmospheric CO2, mainly magmatic, confirmed through measurement of isotopic compositions (δ13CTDIC) and total dissolved inorganic carbon (TDIC) concentrations. A vertical stratification of dissolved CO2 and δ13CTDIC values was observed in the volcanic aquifer at the eastern region of Las Cañadas Caldera. Stratification seems to be controlled by both degree of magmatic CO2-water interaction and CO2 degassing and the original δ13Cco2(g) isotopic composition. The highest dissolved helium (4He) concentrations in groundwater seem to be related to radiogenic contributions resulting from water-rock interactions, and increase with residence time, instead of with endogenous magmatic inputs. Isotopic systematics show that the dissolved gases in groundwater of central Tenerife are variable mixtures of CO2-3He-rich fluids of volcanic-hydrothermal origin with both organic and atmospheric components. The results suggest that the eastern area of Las Cañadas Caldera, the South Volcanic Ridge, and the Teide summit cone are the areas most affected by degassing of the volcanic-hydrothermal system, and they are therefore the most suitable zones for future geochemical monitoring.

  16. Seismic tomography model reveals mantle magma sources of recent volcanic activity at El Hierro Island (Canary Islands, Spain)

    Science.gov (United States)

    García-Yeguas, Araceli; Ibáñez, Jesús M.; Koulakov, Ivan; Jakovlev, Andrey; Romero-Ruiz, M. Carmen; Prudencio, Janire

    2014-12-01

    We present a 3-D model of P and S velocities beneath El Hierro Island, constructed using the traveltime data of more than 13 000 local earthquakes recorded by the Instituto Geográfico Nacional (IGN, Spain) in the period from 2011 July to 2012 September. The velocity models were performed using the LOTOS code for iterative passive source tomography. The results of inversion were thoroughly verified using different resolution and robustness tests. The results reveal that the majority of the onshore area of El Hierro is associated with a high-velocity anomaly observed down to 10-12-km depth. This anomaly is interpreted as the accumulation of solid igneous rocks erupted during the last 1 Myr and intrusive magmatic bodies. Below this high-velocity pattern, we observe a low-velocity anomaly, interpreted as a batch of magma coming from the mantle located beneath El Hierro. The boundary between the low- and high-velocity anomalies is marked by a prominent seismicity cluster, thought to represent anomalous stresses due to the interaction of the batch of magma with crust material. The areas of recent eruptions, Orchilla and La Restinga, are associated with low-velocity anomalies surrounding the main high-velocity block. These eruptions took place around the island where the crust is much weaker than the onshore area and where the melted material cannot penetrate. These results put constraints on the geological model that could explain the origin of the volcanism in oceanic islands, such as in the Canaries, which is not yet clearly understood.

  17. Content of toxic and essential metals in canned mussels commonly consumed in Tenerife, Canary Islands, Spain.

    Science.gov (United States)

    Gutiérrez, Angel; Lozano, Gonzalo; Hardisson, Arturo; Rubio, Carmen; González, Tomás

    2004-07-01

    Concentrations of three toxic heavy metals (Hg, Pb, Cd) and six essential heavy metals (Fe, Zn, Mn, Cr, Cu, Ni) were determined in mussel conserves (Mytilus galloprovincialis, Bivalvia, Mollusca) consumed habitually by individuals in Tenerife (Canary Islands, Spain). A total of 600 samples were analyzed, corresponding to six different commercial brands and four different processing types: pickled sauce (mixture of olive oil, vinegar, red pepper, laurel, and salt), coquille St. Jacques sauce (coquille St. Jacques broth), nature (water and salt), and bionature (water, salt, and soluble vegetal fiber). Samples were collected weekly from markets in Santa Cruz de Tenerife during a 12-month period. All values for toxic metals were lower than the permitted maximum for human consumption as proscribed in European Community Directive 2001/22/CE (1,000 microg/kg wet weight for Pb and Cd) and European Community Decision 93/351/EEC (500 microg/kg wet weight for Hg). For the six essential heavy metals, mussels are a very good source, contributing high percentages of the recommended daily allowance.

  18. Molecular characterization of Acanthamoeba strains isolated from domestic dogs in Tenerife, Canary Islands, Spain.

    Science.gov (United States)

    Valladares, María; Reyes-Batlle, María; Martín-Navarro, Carmen M; López-Arencibia, Atteneri; Dorta-Gorrín, Alexis; Wagner, Carolina; Martínez-Carretero, Enrique; Piñero, José E; Valladares, Basilio; Lorenzo-Morales, Jacob

    2015-06-01

    The present study describes two cases of Acanthamoeba infections (keratitis and ascites/peritonitis) in small breed domestic dogs in Tenerife, Canary Islands, Spain. In both cases, amoebic trophozoites were observed under the inverted microscope and isolated from the infected tissues and/or fluids, without detecting the presence of other viral, fungal or bacterial pathogens. Amoebae were isolated using 2 % non-nutrient agar plates and axenified for further biochemical and molecular analyses. Osmotolerance and thermotolerance assays revealed that both isolates were able to grow up to 37 °C and 1 M of mannitol and were thus considered as potentially pathogenic. Moreover, the strains were classified as highly cytotoxic as they cause more than 75 % of toxicity when incubated with two eukaryotic cell lines. In order to classify the strains at the molecular level, the diagnostic fragment 3 (DF3) region of the 18S rDNA of Acanthamoeba was amplified and sequenced, revealing that both isolates belonged to genotype T4. In both cases, owners of the animals did not allow any further studies or follow-up and therefore the current status of these animals is unknown. Furthermore, the isolation of these pathogenic amoebae should raise awareness with the veterinary community locally and worldwide.

  19. A new species of Didogobius (Teleostei: Gobiidae) from the Canary Islands.

    Science.gov (United States)

    Van Tassell, James L; Kramer, Annemarie

    2014-05-01

    Didogobius helenae is described from the Canary Islands. It has a sensory papillae pattern that is consistent with the current diagnosis for Didogobius, but lacks all head canals and pores that are present in other members of the genus. Pores, in general, are replaced by large papillae.  The species is defined by first dorsal fin VI; second dorsal fin I,10; anal fin I,9; pectoral fin 16-17; pelvic fin I,5 and disk shaped; lateral scales 28-30, cycloid at anterior, becoming ctenoid posteriorly; cycloid scales present on belly and posterior breast; predorsal region, cheek, operculum and base of pectoral fin without scales; lower most scale on the caudal fin-base with elongate, thickened ctenii along the upper and lower posterior edges. Color in life consists of four mottled, wide brown-orange bars separated by narrower white bars on the trunk, the cheek whitish with 5 more or less circular blotches of orange, outlined in dark brown and a black spot on ventral operculum. A key to the species is provided. 

  20. A transversal study on antibodies against selected pathogens in dromedary camels in the Canary Islands, Spain.

    Science.gov (United States)

    Mentaberre, Gregorio; Gutiérrez, Carlos; Rodríguez, Noé F; Joseph, Sunitha; González-Barrio, David; Cabezón, Oscar; de la Fuente, José; Gortazar, Christian; Boadella, Mariana

    2013-12-27

    The Canary Islands contain the most important dromedary camel (Camelus dromedarius) population in the European Union and are the main export point of dromedaries to continental Europe and Latin America. We investigated the presence of antibodies against relevant disease agents in 100 Canarian camel sera. Selected blood samples of the same animals were also tested by PCR. Sera were tested for antibodies against Bluetongue virus (BTV; 0%), Bovine Viral Diarrhoea virus (BVDV; 0%), Camelpox virus (CPV; 8% by serum neutralization, 16% by ELISA), Peste des Petits Ruminants virus (PPRV, 0%), Rift Valley Fever virus (RVFV; 0%) and West Nile Fever virus (WNV; 3%), the bacterial pathogens Anaplasma sp. (3%), Brucella sp. (1%), Coxiella burnetii (19%), Mycobacterium avium paratuberculosis (MAP; 22%), Mycobacterium tuberculosis complex (MTC; 10%) and Rickettsia sp. (83%), and the parasites Toxoplasma gondii (36%) and Neospora caninum (86%). The most remarkable findings were the detection of antibodies against CPV and the high antibody prevalence against C. burnetii, Rickettsia sp., T. gondii and N. caninum. By PCR, we found no C. burnetii, N. caninum and Anaplasma sp. DNA in the tested samples. However, Rickettsia sp. DNA was detected in six antibody positive tested samples. These results should be taken into consideration in order to implement adequate control measures and avoid a potential dissemination of infections to other territories.

  1. Greenhouse gas measurements over a 144 km open path in the Canary Islands

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    J. S. A. Brooke

    2012-05-01

    Full Text Available A new technique for the satellite remote sensing of greenhouse gases in the atmosphere via the absorption of short-wave infrared laser signals transmitted between counter-rotating satellites in low earth orbit has recently been proposed; this would enable the acquisition of a stable, global set of altitude-resolved concentration measurements. We present the first ground-based experimental demonstration of this new technique, in which the atmospheric absorption of CO2 near 2.1 μm was measured over a ~144 km path length between two peaks in the Canary Islands (at an altitude of ~2.4 km. The retrieved CO2 volume mixing ratio of 400.1 ppm (±14.7 ppm is consistent within experimental uncertainty with simultaneously recorded in situ validation measurements. We conclude that the new method has a sound basis for monitoring CO2 and other greenhouse gases in the free atmosphere.

  2. Mantle to surface degassing of carbon- and sulphur-rich alkaline magma at El Hierro, Canary Islands

    Science.gov (United States)

    Longpré, Marc-Antoine; Stix, John; Klügel, Andreas; Shimizu, Nobumichi

    2017-02-01

    Basaltic volcanoes transfer volatiles from the mantle to the surface of the Earth. The quantification of deep volatile fluxes relies heavily on estimates of the volatile content of primitive magmas, the best archive of which is provided by melt inclusions. Available data from volcanoes producing mafic alkaline lavas in a range of tectonic settings suggest high volatile fluxes, but information remains sparse, particularly for intraplate ocean islands. Here we present measurements of volatile and trace element concentrations, as well as sulphur speciation, in olivine-hosted melt inclusions and matrix glasses from quenched basanite lava balloon samples from the 2011-2012 submarine eruption at El Hierro, Canary Islands. The results reveal remarkably high concentrations of dissolved volatiles and incompatible trace elements in this magma, with ∼80 ppm Nb and up to 3420 ppm CO2, 3.0 wt.% H2O and 5080 ppm S. Reconstructed primitive CO2 contents, considering CO2/Nb systematics and possible CO2 sequestration in shrinkage bubbles, reach weight percent levels, indicating that carbon is a major constituent of Canary Island magmas at depth and that exsolution of a CO2-rich fluid begins in the mantle at pressures in excess of 1 GPa. Correlations between sulphur concentration, sulphur speciation and water content suggest strong reduction of an initially oxidised mantle magma, likely controlled by coupled H2O and S degassing. This late-stage redox change may have triggered sulphide saturation, recorded by globular sulphide inclusions in clinopyroxene and ulvöspinel. The El Hierro basanite thus had a particularly high volatile-carrying capacity and released a minimum of 1.3-2.1 Tg CO2 and 1.8-2.9 Tg S to the environment, causing substantial stress on the local submarine ecosystem. These results highlight the important contribution of alkaline ocean island volcanoes, such as the Canary Islands, to volatile fluxes from the mantle.

  3. Photosynthetic response and zonation of three species of Gelidiales from Tenerife, Canary Islands

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    Domíguez-Álvarez, S.

    2011-06-01

    Full Text Available Three species of Gelidiales (Gelidium arbuscula, Gelidium canariense and Pterocladiella capillacea (Rhodophyta were selected due to their abundance in the marine lower intertidal of the north coast of the island of Tenerife (Canary Islands, to assess, using PAM fluorescence, the importance of irradiance and exposure to air on vertical distribution. We compared tolerance to emersion by air-drying fronds under simulated emersion, and results suggest that recovery of photosynthesis after emersion plays a major role in the vertical distribution of these three species. Morphological traits such as clumped fronds explain the higher tolerances, and reduced water loss of the species upper on the shore. Local differences between sites may be related to slight differences in the light regime related to topography.

    Se han seleccionado tres especies de Gelidiales (Gelidium arbuscula, Gelidium canariense y Pterocladiella capillacea que son abundantes en los niveles inferiores del intermareal de la costa N de Tenerife para establecer, utilizando fluorescencia tipo PAM, la importancia de la cantidad de luz y la exposición al aire en su zonación vertical. Se ha comparado la tolerancia a la emersión en frondes expuestas al aire, y los resultados sugieren que la capacidad de recuperación de la fotosíntesis tras la emersión tiene un papel fundamental en la explicación de la posición vertical de estas tres especies. Además, características morfológicas como el apelotonamiento de las frondes pueden coadyuvar a la mayor tolerancia, al reducir la pérdida de agua en emersión en las especies de niveles más altos. Las variaciones entre sitios se pueden deber a desigualdades locales en la cantidad de luz provocadas por diferencias topográficas.

  4. Multiparametric statistical investigation of seismicity occurred at El Hierro (Canary Islands) from 2011 to 2014

    Science.gov (United States)

    Telesca, Luciano; Lovallo, Michele; Lopez, Carmen; Marti Molist, Joan

    2016-03-01

    A detailed statistical investigation of the seismicity occurred at El Hierro volcano (Canary Islands) from 2011 to 2014 has been performed by analysing the time variation of four parameters: the Gutenberg-Richter b-value, the local coefficient of variation, the scaling exponent of the magnitude distribution and the main periodicity of the earthquake sequence calculated by using the Schuster's test. These four parameters are good descriptors of the time and magnitude distributions of the seismic sequence, and their variation indicate dynamical changes in the volcanic system. These variations can be attributed to the causes and types of seismicity, thus allowing to distinguish between different host-rock fracturing processes caused by intrusions of magma at different depths and overpressures. The statistical patterns observed among the studied unrest episodes and between them and the eruptive episode of 2011-2012 indicate that the response of the host rock to the deformation imposed by magma intrusion did not differ significantly from one episode to the other, thus suggesting that no significant local stress changes induced by magma intrusion occurred when comparing between all them. Therefore, despite the studied unrest episodes were caused by intrusions of magma at different depths and locations below El Hierro island, the mechanical response of the lithosphere was similar in all cases. This suggests that the reason why the first unrest culminated in an eruption while the other did not, may be related to the role of the regional/local tectonics acting at that moment, rather than to the forceful of magma intrusion.

  5. On the occurrence of egg masses of the diamond-shaped squid Thysanoteuthis rhombus Troschel, 1857 in the subtropical eastern Atlantic (Canary Islands. A potential commercial species?

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    Alejandro Escanez

    2012-09-01

    Full Text Available Data on opportunistic sightings of diamond-shaped squid Thysanoteuthis rhombus egg masses in the Canary Islands (Atlantic Ocean are presented. A total of 16 egg masses of this species were recorded and photographed from 2000 to 2010 around the western islands of the archipelago (El Hierro, Tenerife and La Gomera. These data reveal the existence of an important spawning area for diamond-shaped squid around the Canary Islands, in subtropical east Atlantic waters. We provide preliminary data for the potential development of an artisanal fishery focused on this species, and a discussion on its potential impacts on the marine ecosystem.

  6. Eighteen years of geochemical monitoring at the oceanic active volcanic island of El Hierro (Canary Islands, Spain)

    Science.gov (United States)

    Asensio-Ramos, María; Alonso, Mar; Sharp, Emerson; Woods, Hannah; Barrancos, José; Pérez, Nemesio M.

    2016-04-01

    We report herein the latest results of a diffuse CO2 efflux survey at El Hierro volcanic system carried out during the summer period of 2015 to constrain the total CO2 output from the studied area a during post-eruptive period. El Hierro Island (278 km2) is the youngest and the SW-most of the Canary Islands. On July 16, 2011, a seismic-volcanic crisis started with the occurrence of more than 11,900 seismic events and significant deformation along the island. On October 10, 2011, the dominant character of seismicity changed dramatically from discrete earthquakes to continuous tremor, a clear indication that magma was rapidly approaching the surface immediately before the onset of the eruption, October 12. Eruption was declared over on 5 March, 2012. In order to monitor the volcanic activity of El Hierro Island, from 1998 to 2015 diffuse CO2 emission studies have been performed at El Hierro volcanic system in a yearly basis (˜600 observation sites) according to the accumulation chamber method. Spatial distribution maps were constructed following the sequential Gaussian simulation (sGs) procedure. To quantify the total CO2 emission from the studied area, 100 simulations for each survey have been performed. During the eruption period, soil CO2 efflux values range from non-detectable (˜0.5 g m-2 d-1) up to 457 g m-2 d-1, reaching in November 27, 2011, the maximum CO2 output estimated value of all time series, 2,398 t d-1, just before the episodes of maximum degassing observed as vigorous bubbling at the sea surface and an increment in the amplitude of the tremor signal. During the 2015 survey, soil CO2 efflux values ranged from non-detectable up to 41 g m-2 d-1. The spatial distribution of diffuse CO2 emission values seemed to be controlled by the main volcano structural features of the island. The total diffuse CO2 output released to atmosphere was estimated at 575 ± 24 t d-1, value slightly higher that the background CO2 emission estimated at 422 t d-1 (Melián et

  7. Serological survey of antibodies to Toxoplasma gondii and Coxiella burnetii in rodents in north-western African islands (Canary Islands and Cape Verde

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    Pilar Foronda

    2015-02-01

    Full Text Available Coxiella burnetii and Toxoplasma gondii are intracellular parasites that cause important reproductive disorders in animals and humans worldwide, resulting in high economic losses. The aim of the present study was to analyse the possible role of peridomestic small mammals in the maintenance and transmission of C. burnetii and T. gondii in the north-western African archipelagos of the Canary Islands and Cape Verde, where these species are commonly found affecting humans and farm animals. Between 2009 and 2013, 108 black rats (Rattus rattus and 77 mice (Mus musculus were analysed for the presence of Coxiella and Toxoplasma antibodies by enzyme-linked immunosorbent assay (ELISA and indirect immunofluorescence (IFA, respectively. Our results showed a wide distribution of C. burnetii and T. gondii, except for T. gondii in Cape Verde, in both rodent species. The overall seroprevalence of C. burnetii antibodies was 12.4%; 21.1% for Cape Verde and 10.2% for the Canary Islands. With respect to T. gondii, seropositive rodents were only observed in the Canary Islands, with an overall seroprevalence of 15%. Considering the fact that both pathogens can infect a large range of hosts, including livestock and humans, the results are of public health and veterinary importance and could be used by governmental entities to manage risk factors and to prevent future cases of Q fever and toxoplasmosis.

  8. Rhizobia from Lanzarote, the Canary Islands, that nodulate Phaseolus vulgars have characteristics in common with Sinorhizobium meliloti isolates from mainland Spain

    Science.gov (United States)

    Common bean and Medicago rhizobia isolated from five locations on the island of Lanzarote, the Canary Islands, by partial analysis of 10 chromosomal genes were shown to exhibit close similarity to Sinorhizobium meliloti. Several bean isolates from Lanzarote, mainland Spain and Tunisia nodulated Leu...

  9. A new Volcanic managEment Risk Database desIgn (VERDI): Application to El Hierro Island (Canary Islands)

    Science.gov (United States)

    Bartolini, S.; Becerril, L.; Martí, J.

    2014-11-01

    One of the most important issues in modern volcanology is the assessment of volcanic risk, which will depend - among other factors - on both the quantity and quality of the available data and an optimum storage mechanism. This will require the design of purpose-built databases that take into account data format and availability and afford easy data storage and sharing, and will provide for a more complete risk assessment that combines different analyses but avoids any duplication of information. Data contained in any such database should facilitate spatial and temporal analysis that will (1) produce probabilistic hazard models for future vent opening, (2) simulate volcanic hazards and (3) assess their socio-economic impact. We describe the design of a new spatial database structure, VERDI (Volcanic managEment Risk Database desIgn), which allows different types of data, including geological, volcanological, meteorological, monitoring and socio-economic information, to be manipulated, organized and managed. The root of the question is to ensure that VERDI will serve as a tool for connecting different kinds of data sources, GIS platforms and modeling applications. We present an overview of the database design, its components and the attributes that play an important role in the database model. The potential of the VERDI structure and the possibilities it offers in regard to data organization are here shown through its application on El Hierro (Canary Islands). The VERDI database will provide scientists and decision makers with a useful tool that will assist to conduct volcanic risk assessment and management.

  10. Experience of the Canary Islands in the development of insular 100% RES systems and micro-grids

    Energy Technology Data Exchange (ETDEWEB)

    Piernavieja, Gonzalo; Suarez, Salvador; Henriquez, Daniel [Instituto Tecnologico de Canarias (Canary Islands Institute of Technology - ITC), Las Palmas, Gran Canaria (Spain). RandD Div.

    2010-07-01

    Given the mentioned circumstances, conventional energy planning in the Canary Islands is a very complex task. The Regional Energy Plan PECAN (2007-2015) tries to correct the existing critical situation setting, among others, the ambitious goal of >25% electricity from RES (mostly wind) for 2015. In parallel to this conventional energy planning, outstanding initiatives in the distributed generation field are underway. ITC vision is that the Canarian Archipelago, given its particular characteristics (insular systems of different sizes, abundant RES potential -different sources-, important natural and biodiversity heritage, etc.), are a laboratory for testing and demonstrating new energy technologies in real conditions, as well as their commercial implementation. These new technologies include energy storage (particularly for excess RES that cannot be absorbed by the grids), development of 100% energy self- sufficiency models (with exclusive use of RES) and micro-/minigrids with high RES penetration and RES forecasting, including advanced ICTs and sustainable mobility concepts (e.g. V2G technologies). Given the high conventional generation costs and the relatively low RES costs (wind electricity production cost is less than 0.03 Euro/kWh), the Canary Islands could in the short term achieve grid parity, and in this sense pioneer the change to a RES based energy system. Models tested on the islands could be exported or extrapolated to our islands, regions of developing countries and even other regions in continental Europe. (orig.)

  11. Volcanic hazard assessment for the Canary Islands (Spain) using extreme value theory, and the recent volcanic eruption of El Hierro

    Science.gov (United States)

    Sobradelo, R.; Martí, J.; Mendoza-Rosas, A. T.; Gómez, G.

    2012-04-01

    The Canary Islands are an active volcanic region densely populated and visited by several millions of tourists every year. Nearly twenty eruptions have been reported through written chronicles in the last 600 years, suggesting that the probability of a new eruption in the near future is far from zero. This shows the importance of assessing and monitoring the volcanic hazard of the region in order to reduce and manage its potential volcanic risk, and ultimately contribute to the design of appropriate preparedness plans. Hence, the probabilistic analysis of the volcanic eruption time series for the Canary Islands is an essential step for the assessment of volcanic hazard and risk in the area. Such a series describes complex processes involving different types of eruptions over different time scales. Here we propose a statistical method for calculating the probabilities of future eruptions which is most appropriate given the nature of the documented historical eruptive data. We first characterise the eruptions by their magnitudes, and then carry out a preliminary analysis of the data to establish the requirements for the statistical method. Past studies in eruptive time series used conventional statistics and treated the series as an homogeneous process. In this paper, we will use a method that accounts for the time-dependence of the series and includes rare or extreme events, in the form of few data of large eruptions, since these data require special methods of analysis. Hence, we will use a statistical method from extreme value theory. In particular, we will apply a non-homogeneous Poisson process to the historical eruptive data of the Canary Islands to estimate the probability of having at least one volcanic event of a magnitude greater than one in the upcoming years. Shortly after the publication of this method an eruption in the island of El Hierro took place for the first time in historical times, supporting our method and contributing towards the validation of

  12. The Continuous Presence of News in the Ballad Tradition of the Canary Islands

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    Monroy Caballero, Andrés

    2008-12-01

    Full Text Available The author approaches the textual study of the oral tradition of ballads in the Canary Islands by focusing on the imprints left on these compositions by the events of History, Big and Small. Known as “Noticierismo”, this expression of popular culture —that of inserting historical news in such texts— has existed in the Islands for quite a long time. By considering the different ballad genres and revealing that noticierismo can be traced back to the late Middle Ages, he argues that its primary function, both in the Islands and elsewhere in the Spanish-speaking world, especially with regard to the 18th Century-like compositions, has been that of spreading the word about those events from the past which most impressed its practitioners. From one generation to the next, the centuries-old tradition has kept the memory of such events alive to the present day.

    Nos acercamos al estudio textual del romancero recogido en la tradición oral de Canarias a través de las huellas que la pequeña o gran historia ha ido perpetuando en estas composiciones, como reflejo de la continuación de la práctica del noticierismo romancístico desde finales de la Edad Media hasta la actualidad. Mediante el análisis de los géneros romancísticos y la persistencia de esta tendencia noticiera en los textos, demostramos que el romancero noticiero en Canarias —y en el mundo hispánico en general— ha estado muy activo (sobre todo en los pliegos dieciochescos, modernos y locales, con la función primordial de dar publicidad a aquellos acontecimientos que más impresionaron en una época pretérita y que se han mantenido vigentes hasta la actualidad gracias a la labor de conservación de sus transmisores.

  13. Spatio-temporal occurrence of eruptions in El Hierro (Canary Islands). Sequential steps for long-term volcanic hazard assessment.

    Science.gov (United States)

    Becerril, Laura; Bartolini, Stefania; Sobradelo, Rosa; Martí, Joan; María Morales, José; Galindo, Inés; Geyer, Adelina

    2014-05-01

    Long term volcanic hazard assessment requires the attainment of several sequential steps, including the compilation of geological and volcanological information, the characterization of past eruptions, spatial and temporal probabilistic studies, and the simulation of different eruptive scenarios to get qualitative and representative results. Volcanic hazard assessment has not been yet systematically conducted in the Canary Islands, in spite of being a densely populated active volcanic region that receives millions of visitors per year. In this paper we focus our attention on El Hierro, the youngest and latest island affected by an eruption in the Canary Islands. We analyze the past eruptive activity (how), the spatial probability (where), and the temporal probability (when) on the island. Looking at the past eruptive behavior of the island, and assuming future eruptive patterns will be similar, we try to identify the most likely set of volcanic scenarios and corresponding hazards that could occur in the future (eg. lava flows, pyroclastic fallout, and pyroclastic density currents) and estimate their probability of occurrence. The final result shows the first volcanic hazard map of the island. This study represents a step forward in the evaluation of long term volcanic hazard at El Hierro Island with regard to previous studies. The obtained results should represent the main pillars on which to build risk mitigation programs as it is required for territorial planning and to develop emergency plans. This research was partially funded by IGME, CSIC and the European Commission (FT7 Theme: ENV.2011.1.3.3-1; Grant 282759: "VUELCO"), and MINECO grant GL2011-16144-E.

  14. Palaeoclimatic considerations of talus flatirons and aeolian deposits in Northern Fuerteventura volcanic island (Canary Islands, Spain)

    Science.gov (United States)

    Gutiérrez-Elorza, Mateo; Lucha, Pedro; Gracia, F.-Javier; Desir, Gloria; Marín, Cinta; Petit-Maire, Nicole

    2013-09-01

    Fuerteventura volcanic island has been subject to considerable aeolian activity since the Late Pleistocene. The aeolian record includes inactive aeolian deposits with interbedded entisols, whose age by OSL dating ranges between 46 and 26 ky BP. The Corralejo active dune field, where sand sheets, nebkhas, coppice dunes, blowouts, barchans and transverse dunes have been described, constitutes a more recent Aeolian deposit. Here the age is about 14 ky BP. On Fuerteventura Island aeolian dust has been deposited on valleys and slopes. This last type of accumulation has been affected by gully incision, producing talus flatirons. Samples taken on the apex of these palaeo-slopes indicate an OSL age of 30 and 50 ky BP. A palaeoclimatic succession has been interpreted during which a prevailing arid period took place in OIS 4, with the accumulation of aeolian dust. A humid period occurred in OIS 2, during which slopes were dissected and formed talus flatirons. An arid period about 14 ky BP gave rise to the Corralejo dune field, which has continued until present with slight climatic oscillations.

  15. Diversity, rarity and the evolution and conservation of the Canary Islands endemic flora

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    Reyes-Betancort, J. Alfredo

    2008-06-01

    Full Text Available The endemic vascular flora of the Canary Islands comprises over 680, taxa collectively accounting for more than 50% of the total native flora. To investigate geographical patterns of diversity within the endemic flora, distribution data from published sources together with other field observation and herbarium data were used to compile a data matrix comprising the distributions of ca. 90% of endemic taxa scored on a 10 × 10km UTM grid. WORLDMAP was then used to investigate patterns of endemic diversity, range size rarity (a measure of endemicity, phylogenetic diversity and threatened taxon richness. Endemic taxon richness was found to be highly heterogeneous across the archipelago, with cells containing between one and 139 taxa each (0.05-22.82% of endemic diversity. Patterns of variation in range size rarity and phylogenetic diversity were found to be largely congruent with endemic diversity, although some cells exhibited markedly higher range size rarity scores than would be predicted by their endemic diversity scores. In contrast, the pattern of endangered taxon richness across the archipelago differed markedly from endemic taxon richness. Many cells in Lanzarote, Fuerteventura and Gran Canaria exhibit higher endangered taxon richness scores than would be predicted from their endemic richness scores whereas in Tenerife, El Hierro, La Palma and La Gomera, the converse is generally true. The implications of the results both for understanding the evolution of Canary Island endemic diversity and for the conservation of the region’s unique and vulnerable flora are considered.La flora vascular endémica de las Islas Canarias comprende unos 680 táxones, lo que viene a representar más del 50% de la flora nativa. Con objeto de investigar patrones geográficos de diversidad en la flora endémica, se recopilaron los datos publicados que, junto con otras observaciones de campo y datos de herbario, sirvieron para completar una matriz de datos

  16. Radial variation in sap flow in five laurel forest tree species in Tenerife, Canary Islands.

    Science.gov (United States)

    Jiménez, M. Soledad; Nadezhdina, Nadezhda; Cermák, Jan; Morales, Domingo

    2000-11-01

    Variations in radial patterns of xylem water content and sap flow rate were measured in five laurel forest tree species (Laurus azorica (Seub.) Franco, Persea indica (L.) Spreng., Myrica faya Ait., Erica arborea L. and Ilex perado Ait. ssp. platyphylla (Webb & Berth.) Tutin) growing in an experimental plot at Agua García, Tenerife, Canary Islands. Measurements were performed around midday during warm and sunny days by the heat field deformation method. In all species, water content was almost constant (around 35% by volume) over the whole xylem cross-sectional area. There were no differences in wood color over the whole cross-sectional area of the stem in most species with the exception of E. arborea, whose wood became darker in the inner layers. Radial patterns of sap flow were highly variable and did not show clear relationships with tree diameter or species. Sap flow occurred over the whole xylem cross-sectional area in some species, whereas it was limited to the outer xylem layers in others. Sap flow rate was either similar along the xylem radius or exhibited a peak in the outer part of the xylem area. Low sap flow rates with little variation in radial pattern were typical for shaded suppressed trees, whereas dominant trees exhibited high sap flow rates with a peak in the radial pattern. Stem damage resulted in a significant decrease in sap flow rate in the outer xylem layers. The outer xylem is more important for whole tree water supply than the inner xylem because of its larger size. We conclude that measurement of radial flow pattern provides a reliable method of integrating sap flow from individual measuring points to the whole tree.

  17. Integrated assessment of air pollution using observations and modelling in Santa Cruz de Tenerife (Canary Islands).

    Science.gov (United States)

    Baldasano, José M; Soret, Albert; Guevara, Marc; Martínez, Francesc; Gassó, Santiago

    2014-03-01

    The present study aims to analyse the atmospheric dynamics of the Santa Cruz de Tenerife region (Tenerife, Canary Islands). This area is defined by the presence of anthropogenic emissions (from a refinery, a port and road traffic) and by very specific meteorological and orographic conditions-it is a coastal area with a complex topography in which there is an interaction of regional atmospheric dynamics and a low thermal inversion layer. These factors lead to specific atmospheric pollution episodes, particularly in relation to SO2 and PM10. We applied a methodology to study these dynamics based on two complementary approaches: 1) the analysis of the observations from the air quality network stations and 2) simulation of atmospheric dynamics using the WRF-ARW/HERMESv2/CMAQ/BSC-DREAM8b and WRF-ARW/HYSPLIT modelling systems with a high spatial resolution (1×1 km(2)). The results of our study show that the refinery plume plays an important role in the maximum SO2 observed levels. The area of maximum impact of the refinery is confined to a radius of 3 km around this installation. A cluster analysis performed for the period: 1998-2011 identified six synoptic situations as predominant in the area. The episodes of air pollution by SO2 occur mainly in those with more limited dispersive conditions, such as the northeastern recirculation, the northwestern recirculation and the western advection, which represent 33.70%, 11.23% and 18.63% of the meteorological situations affecting the study area in the year 2011, respectively. In the case of particulate matter, Saharan dust intrusions result in episodes with high levels of PM10 that may exceed the daily limit value in all measurement station; these episodes occur when the synoptic situation is from the east (3.29% of the situations during the year 2011).

  18. Source areas and long-range transport of pollen from continental land to Tenerife (Canary Islands).

    Science.gov (United States)

    Izquierdo, Rebeca; Belmonte, Jordina; Avila, Anna; Alarcón, Marta; Cuevas, Emilio; Alonso-Pérez, Silvia

    2011-01-01

    The Canary Islands, due to their geographical position, constitute an adequate site for the study of long-range pollen transport from the surrounding land masses. In this study, we analyzed airborne pollen counts at two sites: Santa Cruz de Tenerife (SCO), at sea level corresponding to the marine boundary layer (MBL), and Izaña at 2,367 m.a.s.l. corresponding to the free troposphere (FT), for the years 2006 and 2007. We used three approaches to describe pollen transport: (1) a classification of provenances with an ANOVA test to describe pollen count differences between sectors; (2) a study of special events of high pollen concentrations, taking into consideration the corresponding meteorological synoptic pattern responsible for transport and back trajectories; and (3) a source-receptor model applied to a selection of the pollen taxa to show pollen source areas. Our results indicate several extra-regional pollen transport episodes to Tenerife. The main provenances were: (1) the Mediterranean region, especially the southern Iberian Peninsula and Morocco, through the trade winds in the MBL. These episodes were characterized by the presence of pollen from trees (Casuarina, Olea, Quercus perennial and deciduous types) mixed with pollen from herbs (Artemisia, Chenopodiaceae/Amaranthaceae and Poaceae wild type). (2) The Saharan sector, through transport at the MBL level carrying pollen principally from herbs (Chenopodiaceae-Amaranthaceae, Cyperaceae and Poaceae wild type) and, in one case, Casuarina pollen, uplifted to the free troposphere. And (3) the Sahel, characterized by low pollen concentrations of Arecaceae, Chenopodiaceae-Amaranthaceae, Cyperaceae and Poaceae wild type in sporadic episodes. This research shows that sporadic events of long-range pollen transport need to be taken into consideration in Tenerife as possible responsible agents in respiratory allergy episodes. In particular, it is estimated that 89-97% of annual counts of the highly allergenous Olea

  19. Estimating building exposure and impact to volcanic hazards in Icod de los Vinos, Tenerife (Canary Islands)

    Science.gov (United States)

    Marti, J.; Spence, R.; Calogero, E.; Ordoñez, A.; Felpeto, A.; Baxter, P.

    2008-12-01

    Principal and subsidiary building structure characteristics and their distribution have been inventoried in Icod, Tenerife (Canary Islands) and used to evaluate the vulnerability of individual buildings to three volcanic hazards: tephra fallout, volcanogenic earthquakes and pyroclastic flows. The procedures described in this paper represent a methodological framework for a comprehensive survey of all the buildings at risk in the area around the Teide volcano in Tenerife. Such a methodology would need to be implemented for the completion of a comprehensive risk assessment for the populations under threat of explosive eruptions in this area. The information presented in the paper is a sample of the necessary data required for the impact estimation and risk assessment exercises that would need to be carried out by emergency managers, local authorities and those responsible for recovery and repair in the event of a volcanic eruption. The data shows there are micro variations in building stock characteristics that would influence the likely impact of an eruption in the area. As an example of the use of this methodology for vulnerability assessment, we have applied a deterministic simulation model of a volcanic eruption from Teide volcano and its associated ash fallout which, when combined with the vulnerability data collected, allows us to obtain the vulnerability map of the studied area. This map is obtained by performing spatial analysis with a Geographical Information System (GIS). This vulnerability analysis is included in the framework of an automatic information system specifically developed for hazard assessment and risk management on Tenerife, but which can be also applied to other volcanic areas. The work presented is part of the EU-funded EXPLORIS project (Explosive Eruption Risk and Decision Support for EU Populations Threatened by Volcanoes, EVR1-2001-00047).

  20. Source areas and long-range transport of pollen from continental land to Tenerife (Canary Islands)

    Science.gov (United States)

    Izquierdo, Rebeca; Belmonte, Jordina; Avila, Anna; Alarcón, Marta; Cuevas, Emilio; Alonso-Pérez, Silvia

    2011-01-01

    The Canary Islands, due to their geographical position, constitute an adequate site for the study of long-range pollen transport from the surrounding land masses. In this study, we analyzed airborne pollen counts at two sites: Santa Cruz de Tenerife (SCO), at sea level corresponding to the marine boundary layer (MBL), and Izaña at 2,367 m.a.s.l. corresponding to the free troposphere (FT), for the years 2006 and 2007. We used three approaches to describe pollen transport: (1) a classification of provenances with an ANOVA test to describe pollen count differences between sectors; (2) a study of special events of high pollen concentrations, taking into consideration the corresponding meteorological synoptic pattern responsible for transport and back trajectories; and (3) a source-receptor model applied to a selection of the pollen taxa to show pollen source areas. Our results indicate several extra-regional pollen transport episodes to Tenerife. The main provenances were: (1) the Mediterranean region, especially the southern Iberian Peninsula and Morocco, through the trade winds in the MBL. These episodes were characterized by the presence of pollen from trees ( Casuarina, Olea, Quercus perennial and deciduous types) mixed with pollen from herbs ( Artemisia, Chenopodiaceae/Amaranthaceae and Poaceae wild type). (2) The Saharan sector, through transport at the MBL level carrying pollen principally from herbs (Chenopodiaceae-Amaranthaceae, Cyperaceae and Poaceae wild type) and, in one case, Casuarina pollen, uplifted to the free troposphere. And (3) the Sahel, characterized by low pollen concentrations of Arecaceae, Chenopodiaceae-Amaranthaceae, Cyperaceae and Poaceae wild type in sporadic episodes. This research shows that sporadic events of long-range pollen transport need to be taken into consideration in Tenerife as possible responsible agents in respiratory allergy episodes. In particular, it is estimated that 89-97% of annual counts of the highly allergenous Olea

  1. Transient changes in bacterioplankton communities induced by the submarine volcanic eruption of El Hierro (Canary Islands.

    Directory of Open Access Journals (Sweden)

    Isabel Ferrera

    Full Text Available The submarine volcanic eruption occurring near El Hierro (Canary Islands in October 2011 provided a unique opportunity to determine the effects of such events on the microbial populations of the surrounding waters. The birth of a new underwater volcano produced a large plume of vent material detectable from space that led to abrupt changes in the physical-chemical properties of the water column. We combined flow cytometry and 454-pyrosequencing of 16S rRNA gene amplicons (V1-V3 regions for Bacteria and V3-V5 for Archaea to monitor the area around the volcano through the eruptive and post-eruptive phases (November 2011 to April 2012. Flow cytometric analyses revealed higher abundance and relative activity (expressed as a percentage of high-nucleic acid content cells of heterotrophic prokaryotes during the eruptive process as compared to post-eruptive stages. Changes observed in populations detectable by flow cytometry were more evident at depths closer to the volcano (~70-200 m, coinciding also with oxygen depletion. Alpha-diversity analyses revealed that species richness (Chao1 index decreased during the eruptive phase; however, no dramatic changes in community composition were observed. The most abundant taxa during the eruptive phase were similar to those in the post-eruptive stages and to those typically prevalent in oceanic bacterioplankton communities (i.e. the alphaproteobacterial SAR11 group, the Flavobacteriia class of the Bacteroidetes and certain groups of Gammaproteobacteria. Yet, although at low abundance, we also detected the presence of taxa not typically found in bacterioplankton communities such as the Epsilonproteobacteria and members of the candidate division ZB3, particularly during the eruptive stage. These groups are often associated with deep-sea hydrothermal vents or sulfur-rich springs. Both cytometric and sequence analyses showed that once the eruption ceased, evidences of the volcano-induced changes were no longer

  2. Transient Changes in Bacterioplankton Communities Induced by the Submarine Volcanic Eruption of El Hierro (Canary Islands)

    Science.gov (United States)

    Ferrera, Isabel; Arístegui, Javier; González, José M.; Montero, María F.; Fraile-Nuez, Eugenio; Gasol, Josep M.

    2015-01-01

    The submarine volcanic eruption occurring near El Hierro (Canary Islands) in October 2011 provided a unique opportunity to determine the effects of such events on the microbial populations of the surrounding waters. The birth of a new underwater volcano produced a large plume of vent material detectable from space that led to abrupt changes in the physical-chemical properties of the water column. We combined flow cytometry and 454-pyrosequencing of 16S rRNA gene amplicons (V1–V3 regions for Bacteria and V3–V5 for Archaea) to monitor the area around the volcano through the eruptive and post-eruptive phases (November 2011 to April 2012). Flow cytometric analyses revealed higher abundance and relative activity (expressed as a percentage of high-nucleic acid content cells) of heterotrophic prokaryotes during the eruptive process as compared to post-eruptive stages. Changes observed in populations detectable by flow cytometry were more evident at depths closer to the volcano (~70–200 m), coinciding also with oxygen depletion. Alpha-diversity analyses revealed that species richness (Chao1 index) decreased during the eruptive phase; however, no dramatic changes in community composition were observed. The most abundant taxa during the eruptive phase were similar to those in the post-eruptive stages and to those typically prevalent in oceanic bacterioplankton communities (i.e. the alphaproteobacterial SAR11 group, the Flavobacteriia class of the Bacteroidetes and certain groups of Gammaproteobacteria). Yet, although at low abundance, we also detected the presence of taxa not typically found in bacterioplankton communities such as the Epsilonproteobacteria and members of the candidate division ZB3, particularly during the eruptive stage. These groups are often associated with deep-sea hydrothermal vents or sulfur-rich springs. Both cytometric and sequence analyses showed that once the eruption ceased, evidences of the volcano-induced changes were no longer observed

  3. Melt inclusion study of the most recent basanites from El Hierro and Lanzarote, Canary Islands

    Science.gov (United States)

    Gomez-Ulla, Alejandra; Sigmarsson, Olgeir; Huertas, Maria Jose; Ancochea, Eumenio

    2015-04-01

    The latest eruptions of both Lanzarote (one of the oldest and easternmost of the Canary Island archipelago) and El Hierro (the youngest and westernmost) produced basanite lavas. Major, volatile and trace element concentrations of melt inclusion (MI) hosted in olivine for both eruptions have been analysed. The basanites display primitive mantle normalized trace element spectra suggesting a magma source largely composed of recycled oceanic crust. In addition, beneath Lanzarote an interaction with a carbonatitic fluid phase or metasome would explain eccentric Ba/U and other trace element ratios. Contribution of carbonatitic component would readily account for extremely volatile-rich (Cl, F, S) MI from Lanzarote (Cl=1577-2500 ppm) whereas the maximum for El Hierro is 1080 ppm. The submarine character of the 2011-12 eruption off El Hierro appears to have affected the degassing behavior, whereas estimated sulfur emission to the atmosphere during the historical Lanzarote eruptions are amongst the highest observed so far. An estimated magma volume (VDRE) of 0.02 km3 yields atmospheric mass loading of 0.2 Mt SO2 from the 1824 Lanzarote eruption. Scaling the volume of the 1824 Lanzarote eruption to that of the previous Timanfaya eruption (1730-6; 5 km3) results in estimated 12 Mt SO2, an atmospheric mass loading only outnumbered by the historical Laki and Eldgjá eruptions in Iceland. The significantly greater volatile budget of basanites from Lanzarote compared to El Hierro is thus controlled by more fertile source composition closer to the African continent.

  4. Family influences in academic achievement. A study of the Canary Islands

    Directory of Open Access Journals (Sweden)

    Pérez Sánchez, Carmen Nieves

    2013-04-01

    Full Text Available In this paper we study the family variables affecting academic achievement within a Canary Island sample. Parents’ level of education, parents’ expectations about academic achievement, Socioeconomic Status (SES, family size, type of family and parents’ control over the student’s homework are used as predicting variables in a logistic regression for predicting which variables load in high academic achievement. These variables are incorporated into two different theoretical models: the social capital view of Coleman and the cultural capital view of Bourdieu. The results indicate that the variables having a leading role are parents’ expectations, parents’ education, SES and family size.

    En este artículo estudiamos los efectos de las variables relacionadas con la familia en el rendimiento académico en una muestra de estudiantes de Canarias. A través de una regresión logística evaluamos el peso de las siguientes variables en el rendimiento académico: el nivel educativo de los padres, las expectativas de los padres sobre el rendimiento académico de sus hijos, el estatus socioeconómico, el tamaño de la familia, tipo de familia y prácticas de control familiar sobre el trabajo escolar. Estas variables son incorporadas a dos modelos teóricos diferentes: el de Coleman y el de Bourdieu. Los resultados indican que las variables que tienen un papel destacado son: las expectativas, el nivel educativo, el estatus socioeconómico de los padres y el tamaño de la familia.

  5. 3D Attenuation Tomography of the Volcanic Island of Tenerife (Canary Islands)

    Science.gov (United States)

    Prudencio, J.; Ibáñez, J. M.; Del Pezzo, E.; Martí, J.; García-Yeguas, A.; De Siena, L.

    2015-09-01

    This paper shows a new multidisciplinary interpretation approach to the internal structure of Tenerife Island. The central core of this work is the determination of the three-dimensional attenuation structure of the region using P-waves and the coda normalization method. This study has been performed using 45,303 seismograms recorded at 85 seismic stations from an active experiment (air gun shots) conducted in January 2007. The interpretation of these new results is done combining the new images with previous studies performed in the area such as seismic velocity tomography, magnetic structure, magnetotelluric surveys or gravimetric models. Our new 3D images indicate the presence of seismic attenuation contrasts, with areas of high and low seismic attenuation patterns. High seismic attenuation zones are observed both in shallow and in deeper areas. The shallowest area of Las Cañadas caldera complex (1-3 km thick) is dominated by high attenuation behavior, and it is interpreted as the combined effect of sedimentary and volcanoclastic deposits, multifracture systems and the presence of shallow aquifers. At the same time, the deeper analyzed area, more than 8 km below sea level, is dominated by a high attenuation pattern, and it is interpreted as the consequence of the effect of high-temperature rocks in the crustal-mantle boundary. This interpretation is compatible and confirmed by previous models that indicate the presence of underplating magma in this region. On the contrary, some low attenuation bodies and structures have been identified at different depths. A deep low attenuation central body is interpreted as the original central structure associated with the early stage of Tenerife Island. At shallower depths, some low attenuation bodies are compatible with old intermediate magmatic chambers postulated by petrological studies. Finally, in the north of the island (La Orotava valley) we can interpret the low attenuation structure as the headwall of this valley

  6. A methodology for optimization of wind farm allocation under land restrictions: the case of the Canary Islands

    Science.gov (United States)

    Castaño Moraga, C. A.; Suárez Santana, E.; Sabbagh Rodríguez, I.; Nebot Medina, R.; Suárez García, S.; Rodríguez Alvarado, J.; Piernavieja Izquierdo, G.; Ruiz Alzola, J.

    2010-09-01

    Wind farms authorization and power allocations to private investors promoting wind energy projects requires some planification strategies. This issue is even more important under land restrictions, as it is the case of Canary Islands, where numerous specially protected areas are present for environmental reasons and land is a scarce resource. Aware of this limitation, the Regional Government of Canary Islands designed the requirements of a public tender to grant licences to install new wind farms trying to maximize the energy produced in terms of occupied land. In this paper, we detail the methodology developed by the Canary Islands Institute of Technology (ITC, S.A.) to support the work of the technical staff of the Regional Ministry of Industry, responsible for the evaluation of a competitive tender process for awarding power lincenses to private investors. The maximization of wind energy production per unit of area requires an exhaustive wind profile characterization. To that end, wind speed was statistically characterized by means of a Weibull probability density function, which mainly depends on two parameters: the shape parameter K, which determines the slope of the curve, and the average wind speed v , which is a scale parameter. These two parameters have been evaluated at three different heights (40,60,80 m) over the whole canarian archipelago, as well as the main wind speed direction. These parameters are available from the public data source Wind Energy Map of the Canary Islands [1]. The proposed methodology is based on the calculation of an initially defined Energy Efficiency Basic Index (EEBI), which is a performance criteria that weighs the annual energy production of a wind farm per unit of area. The calculation of this parameter considers wind conditions, windturbine characteristics, geometry of windturbine distribution in the wind farm (position within the row and column of machines), and involves four steps: Estimation of the energy produced by

  7. New structural, hydrogeological and hydrothermal insights on Cumbre Vieja (La Palma, Canary Islands, Spain)

    Science.gov (United States)

    Barde-Cabusson, S.; Finizola, A.; Torres, P.; Víctor Villasante-Marcos, V.; Abella, R.; Aragó, S.; Berthod, C.; Ibarra, P.; Geyer Traver, A.

    2013-12-01

    Determining the link between shallow structure and volcanism is a topic of interest in Volcanology. We carried out a geophysical study devoted to the characterization of the major structural limits influencing volcanic hydrothermal activity and underground meteoric circulations in La Palma (Canary Islands). Since 1 Ma volcanic activity concentrates at the southern half of the island, on the Cumbre Vieja volcanic rift-zone. During the 1949 eruption a N-S fault system, facing west, developed in the summit area of Cumbre Vieja. This was interpreted as the surface expression of an incipient deformation zone on the western flank. The distribution of the recent activity and faulting indicate that a discontinuity may be present beneath the western flank of Cumbre Vieja, along which a future collapse may occur. Our study, which combines the application of self-potential and soil temperature measurements, provides new information to characterize and locate the limits guiding upward or downward fluid circulation and possibly associated to future failures and potential landslides on the Cumbre Vieja rift-zone. We found a clear asymmetry of the self-potential signal between the eastern and the western flanks of Cumbre Vieja. Strong infiltration of meteoric water seems to affect most of the summit axis while we observe poor variation in the self-potential values on the western flank. This could be explained by a constant thickness of the vadose zone on this flank, i.e., the presence of an impermeable layer at constant depth. This layer could correspond to the landslide interface associated to the previous Cumbre Nueva edifice destruction, on which Cumbre Vieja is currently growing. This constant self-potential pattern is interrupted by at least one other main infiltration zone, near Tajuya volcano, at 1200 m a.s.l. on the western flank, where field observation allowed identifying a small horst-graben system. However it is not clear if this fault system results from local

  8. Analysis of Ballistic Blocks and Eruption History of Montaña Colorada, Lanzarote, Canary Islands

    Science.gov (United States)

    Semple Domagall, A. M.; Kobs-Nawotniak, S. E.

    2015-12-01

    From September 1730 to April 1736, more than 30 vents formed along a ~18 km long rift on the island of Lanzarote in the Canary Islands. Little actual data of these eruptions exist with the exception of court records and the diary of a priest from Yaiza. Previous research has broken this five and a half year period into 5 major eruptive phases (Carracedo et al., 1992).Montaña Colorada - a 150 m-tall, 600 m wide cinder cone - is the final vent associated with this eruption, and likely formed in 10 km long), large spatter clasts, spatter within the cinder cone, and a minor ash blanket are associated with this vent. These are typical of the 1730-1736 vents on Lanzarote. Unique to Montaña Colorada is the presence of a solidified lava pond within the vent, and an array of large (~1-4 m diameter), dense (2800 kg/m3), basaltic blocks roughly 500-1000 m from the vent. Additionally, peridotite nodules (up to 15 cm diameter) are found both within the lava flows and the tephra: the nodules are seen only here and at the, nearby, first vent associated with the eruptions. Lava flows, possibly from a fissure vent, started the eruption at Montaña Colorada: an effusion rate of 74.9 ± 25.9 m3s-1 is estimated for the 10.6 km-long, peridotite-bearing, flow, giving an emplacement time of ~1-3 days. As the eruption rate decreased, agglutinated spatter collected closer to the vent with loose tephra distally forming the main cinder cone. Towards the end of the eruption it appears the vent was filled with a lava pond, which breached to the north. The large, dense, blocks surrounding Montaña Colorada are here suggested to be the result of a transient explosion of a previous lava pond that occupied the vent. A lack of peridotite nodules or vesicles would be consistent with basalt that had pooled within the vent for some time. Eruption velocities on the order of 70-300 ms-1 are calculated for these blocks.

  9. Network of marine environmental observation, surveillance and control in the canary islands waters (red acomar)

    Science.gov (United States)

    Rueda, M. J.; Villagarcía, M. G.; Barrera, C.; Pérez, J.; Cianca, A.; Godoy, J.; Maroto, L.; Cardona, L.; Llinás, O.

    2003-04-01

    intended to use the observations made at station ESTOC (European Station for Time Series in the Ocean Canary Islands) as a reference to parameters linked to waters not altered by anthropogenic influences. Altogether, it is pursued that all the network will be the Canarian contribution to the GOOS initiative.

  10. Burned and devoured-Introduced herbivores, fire, and the endemic flora of the high-elevation ecosystem on La Palma, Canary Islands

    OpenAIRE

    Irl, Severin D. H.; Steinbauer, Manuel; Messinger, Jana; Blume-Werry, Gesche; Palomares-Martinez, Angel; Beierkuhnlein, Carl; Jentsch, Anke

    2014-01-01

    Novel disturbance regimes (e.g., introduced herbivores and fire) are among the major drivers of degradation in island ecosystems. High-elevation ecosystems (HEEs) on islands might be especially vulnerable to these disturbances due to high endemism. Here, data from an 11-year exclosure experiment in the HEE of La Palma (Canary Islands) are presented where mammalian herbivores have been introduced. We investigate the combined effect of herbivory and fire on total species richness, seedling rich...

  11. Three-armed rifts or masked radial pattern of eruptive fissures? The intriguing case of El Hierro volcano (Canary Islands)

    Science.gov (United States)

    Becerril, L.; Galindo, I.; Martí, J.; Gudmundsson, A.

    2015-04-01

    Using new surface structural data as well as subsurface structural data obtained from seventeen water galleries, we provide a comprehensive model of the volcano-tectonic evolution of El Hierro (Canary Islands). We have identified, measured and analysed more than 1700 volcano-structural elements including vents, eruptive fissures, dykes and faults. The new data provide important information on the main structural patterns of the island and on its stress and strain fields, all of which are crucial for reliable hazard assessments. We conducted temporal and spatial analyses of the main structural elements, focusing on their relative age and association with the three main cycles in the construction of the island: the Tiñor Edifice, the El Golfo-Las Playas Edifice, and the Rift Volcanism. A radial strike distribution, which can be related to constructive episodes, is observed in the on-land structures. A similar strike distribution is seen in the submarine eruptive fissures, which are radial with respect to the centre of the island. However, the volcano-structural elements identified onshore and reflecting the entire volcano-tectonic evolution of the island also show a predominant NE-SW strike, which coincides with the main regional trend of the Canary archipelago as a whole. Two other dominant directions of structural elements, N-S and WNW-ESE, are evident from the establishment of the El Golfo-Las Playas edifice, during the second constructive cycle. We suggest that the radial-striking structures reflect comparatively uniform stress fields during the constructive episodes, mainly conditioned by the combination of overburden pressure, gravitational spreading, and magma-induced stresses in each of the volcanic edifices. By contrast, in the shallower parts of the edifice the NE-SW, N-S and WNW-ESE-striking structures reflect local stress fields related to the formation of mega-landslides and masking the general and regional radial patterns.

  12. A biological quality index for volcanic Andisols and Aridisols (Canary Islands, Spain): variations related to the ecosystem degradation.

    Science.gov (United States)

    Armas, Cecilia María; Santana, Bayanor; Mora, Juan Luis; Notario, Jesús Santiago; Arbelo, Carmen Dolores; Rodríguez-Rodríguez, Antonio

    2007-05-25

    The aim of this work is to identify indicators of biological activity in soils from the Canary Islands, by studying the variation of selected biological parameters related to the processes of deforestation and accelerated soil degradation affecting the Canarian natural ecosystems. Ten plots with different degrees of maturity/degradation have been selected in three typical habitats in the Canary Islands: laurel forest, pine forest and xerophytic scrub with Andisols and Aridisols as the most common soils. The studied characteristics in each case include total organic carbon, field soil respiration, mineralized carbon after laboratory incubation, microbial biomass carbon, hot water-extractable carbon and carboxymethylcellulase, beta-d-glucosidase and dehydrogenase activities. A Biological Quality Index (BQI) has been designed on the basis of a regression model using these variables, assuming that the total soil organic carbon content is quite stable in nearly mature ecosystems. Total carbon in mature ecosystems has been related to significant biological variables (hot water-extractable carbon, soil respiration and carboxymethylcellulase, beta-d-glucosidase and dehydrogenase activities), accounting for nearly 100% of the total variance by a multiple regression analysis. The index has been calculated as the ratio of the value calculated from the regression model and the actual measured value. The obtained results show that soils in nearly mature ecosystems have BQI values close to unit, whereas those in degraded ecosystems range between 0.24 and 0.97, depending on the degradation degree.

  13. Electricity generation cost in isolated system: The complementarities of natural gas and renewables in the Canary Islands

    Energy Technology Data Exchange (ETDEWEB)

    Marrero, Gustavo A. [Facultad de Ciencias Economicas, Campus de Guajara, Universidad de La Laguna, 38071 Santa Cruz de Tenerife (Canary Islands) (Spain); Fundacion de Estudios de Economia Aplicada (FEDEA), C/Jorge Juan 46, 28001 Madrid (Spain); Ramos-Real, Francisco Javier [Facultad de Ciencias Economicas, Campus de Guajara, Universidad de La Laguna, 38071 Santa Cruz de Tenerife (Canary Islands) (Spain); Instituto Universitario de Desarrollo Regional, Facultad de Ciencias Economicas, Campus de Guajara, Universidad de La Laguna, 38071 Santa Cruz de Tenerife (Canary Islands) (Spain)

    2010-12-15

    The Canary Islands offer an example of an isolated electric grid of relative important size within the EU. Due to its peculiarities, the role of renewable energies and their complementarity with fossil fuels offers a solid path to achieving the main energy policy goals of the Islands. The purpose of this paper is to assess the current situation and the energy objectives proposed in the Energy Plan of the Canaries (PECAN, 2006) for the electricity industry, taking into account the average cost and the risk associated with the different alternatives for generating electricity by means of the Mean-Variance Portfolio Theory. Our analysis highlights the inefficiency of the current electricity generating mix in terms of cost, risk and lack of diversification. Shifting toward an efficient system would involve optimizing the use of endogenous energy sources and introducing natural gas to generate electricity. This scenario would mean reducing both cost and risk by almost 30% each, as well as atmospheric CO{sub 2} emissions. Our results agree with the PECAN philosophy. (author)

  14. Identification of a subtropical cyclone in the proximity of the Canary Islands and its analysis by numerical modeling

    Science.gov (United States)

    Quitián-Hernández, L.; Martín, M. L.; González-Alemán, J. J.; Santos-Muñoz, D.; Valero, F.

    2016-09-01

    Subtropical cyclones (STC) are low-pressure systems that share tropical and extratropical characteristics. Because of the great economic and social damage, the study of these systems has recently grown. This paper analyzes the cyclone formed in October 2014 near the Canary Islands and diagnoses such a cyclone in order to identify its correspondence to an STC category, examining its dynamical and thermal evolution. Diverse fields have been obtained from three different numerical models, and several diagnostic tools and cyclone phase space diagrams have been used. An extratropical cyclone, in its early stage, experimented a process of cut-off and isolation from the midlatitude flow. The incursion of a trough in conjunction with a low-level baroclinic zone favored the formation of the STC northwestern of the Canary Islands. Streamers of high potential vorticity linked to the cyclone favored strong winds and precipitation in the study domain. Cyclone phase space diagrams are used to complement the synoptic analysis and the satellite images of the cyclone to categorize such system. The diagrams reveal the transition from extratropical cyclone to STC remaining for several days with a subtropical structure with a quite broad action radius. The study of the mesoscale environment parameters showed an enhanced conditional instability through a deep troposphere layer. It is shown that moderate to strong vertical wind shear together with relatively warm sea surface temperature determine conditions enabling the development of long-lived convective structures.

  15. Association of the European lactase persistence variant (LCT-13910 C>T polymorphism with obesity in the Canary Islands.

    Directory of Open Access Journals (Sweden)

    Ricardo Almon

    Full Text Available BACKGROUND: European lactose tolerance genotype (LCT -13910 C>T, rs4988234 has been positively associated to body mass indexes (BMI in a meta-analysis of 31,720 individuals of northern and central European descent. A strong association of lactase persistence (LP with BMI and obesity has also been traced in a Spanish Mediterranean population. The aim of this study was to analyze a potential association of LP compared to lactase non-persistence (LNP with BMI in inhabitants of the Canary Islands of Spain using Mendelian randomization. METHODS: A representative, randomly sampled population of adults belonging to the Canary Islands Nutrition Survey (ENCA in Spain, aged 18-75 years (n = 551, was genotyped for the LCT - 13910 C>T polymorphism. Milk consumption was assessed by a validated questionnaire. Anthropometric variables were directly measured. WHO classification of BMI was used. RESULTS: LP individuals were significantly more obese than LNP subjects (χ(2 = 10.59; pT polymorphism is positively associated with BMI. LP increases significantly the risk to develop obesity in the studied population. The LCT-13910 C>T polymorphism stands proxy for the lifetime exposure pattern, milk intake, that may increase susceptibility to obesity and to obesity related pathologies.

  16. Geomechanical parameters of intact rocks and rock masses from the Canary Islands: Implications on their flank stability

    Science.gov (United States)

    Rodríguez-Losada, J. A.; Hernández-Gutiérrez, L. E.; Olalla, C.; Perucho, A.; Serrano, A.; Eff-Darwich, A.

    2009-05-01

    New data on the geomechanical properties of the highly cohesive volcanic rocks of the Canary Archipelago and their role in the flank stability on oceanic islands are provided in this work. On the basis of the textural and petrological features, a preliminary classification of rocks, grouped into lithotypes, was carried out. This classification includes vesicular and non vesicular basalts, trachybasalts, trachytes, phonolites, welded and non welded ignimbrites. Strength and strain-related features are summarized here for each distinctive lithotype. Taking into account the results of the uniaxial and triaxial compressive tests, the geological strength index of rock masses and their textural-structural features, an estimate of the rock mass parameters and Mohr-Coulomb fit has been carried out. A final discussion on the impact of those geomechanical parameters as factors governing the stability of steep slopes in volcanic islands is then made here as a contribution in volcanic risk.

  17. Metals in Mullus surmuletus and Pseudupeneus prayensis from the Canary Islands (Atlantic Ocean).

    Science.gov (United States)

    Dorta, Paola; Rubio, Carmen; Lozano, Gonzalo; González-Weller, Dailos; Gutiérrez, Ángel; Hardisson, Arturo; Revert, Consuelo

    2015-12-01

    A total of 20 metals (Na, K, Ca, Mg, B, Ba, Co, Cr, Cu, Sr, Fe, Li, Mn, Mo, Ni, V, Zn, Al, Cd, and Pb) were analyzed by inductively coupled plasma optical emission spectrometry in muscle and liver tissue from a total of 28 examples of the fishes Mullus surmuletus and Pseudupeneus prayensis marketed in Tenerife, Canary Islands (Spain). Significant differences (P < 0.05) in B, K, Mg, Mn, and Na concentrations were found between muscle and liver. The mean concentrations of K (1,388.04 mg/kg wet weight [wet wt]) and Mg (153.33 mg/kg wet wt) were higher in muscle than in liver (697.49 and 114.21 mg/kg wet wt, respectively). The mean concentrations of B in liver (0.18 mg/kg wet wt), Mn (0.70 mg/kg wet wt), and Na (892.09 mg/kg wet wt) were higher than those in muscle (0.15, 0.11, and 375.55 mg/kg wet wt, respectively). The mean concentrations of Al, Cd, and Pb in muscle tissue were 2.72 mg/kg wet wt and 4.28 and 10.29 μg/kg wet wt, and those in liver tissue were 31.31 mg/kg wet wt and 612.91 and 232.08 μg/kg wet wt, respectively. When comparing the two fish species, the muscle tissue of M. surmuletus has significantly higher concentrations (P < 0.05) of Al, B, Ba, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Sr, and Zn than did P. prayensis muscle, whereas the concentrations of Cd and V were significantly higher (P < 0.05) in P. prayensis muscle. Toxicological assessment of Cd and Pb concentrations was performed using the maximum limits set by the European Commission Regulations 1881/2006 and 629/2008 for muscle tissue (50 and 300 μg/kg wet wt, respectively). The concentrations of Cd and Pb in muscle detected in the present study for all the analyzed examples of M. surmuletus and P. prayensis were lower than the maximums established for muscle tissue by European legislation. Therefore, consumption of the muscle of these fish is considered safe in terms of Al, Cd, and Pb concentrations. However, the consumption of liver tissue should be avoided because of its high levels

  18. Prenatal and Postnatal Exposure to DDT by Breast Milk Analysis in Canary Islands

    Science.gov (United States)

    Vall, Oriol; Gomez-Culebras, Mario; Puig, Carme; Rodriguez-Carrasco, Ernesto; Gomez Baltazar, Arelis; Canchucaja, Lizzeth; Joya, Xavier; Garcia-Algar, Oscar

    2014-01-01

    Introduction The use of p,p′-dichlorodiphenyltrichloroethane (DDT) has been banned since the late 1970s due to its toxicity. However, its long half-life makes it persistent in the environment and, consequently, almost everyone has DDT residues in the body. Human milk constitutes an ideal non-conventional matrix to investigate environmental chronic exposure to organochlorine compounds (OCs) residues. The study aimed to identify potential population risk factors of exposure to DDT due to the proximity to countries where it is still used. Methods Seventy-two consecutive lactating women were prospectively included in Tenerife, Canary Islands (Spain). A validated questionnaire was used to obtain socioeconomic, demographics data, and daily habits during pregnancy. DDT levels in breast milk were measured by gas chromatography with-electron capture detector (GC-ECD). Anthropometrics measurements in newborns were obtained. Results Thirty-four out of 72 (47.2%) of the analysed milk samples presented detectable levels of DDT (mean: 0.92 ng/g), ranging between 0.08 to 16.96 ng/g. The socio-demographic variables did not significantly differ between detectable DDT and non-detectable DDT groups. We found positive association between DDT levels and vegetables (OR (95%CI): 1.23 (1.01–1.50)) and poultry meat (OR (95%CI): 2.05 (1.16–3.60)) consumption, and also between the presence of DDT in breast milk and gestational age (OR (95%CI): 0.59 (0.40–0.90)). Conclusions DDT is present in breast milk of women at the time of delivery. Residual levels and the spread from countries still using DDT explain DDT detection from vegetables and from animal origin food. The presence of this compound in breast milk represents a pre- and postnatal exposure hazard for foetuses and infants due to chronic bioaccumulation and poor elimination, with possible deleterious effects on health. This data should be used to raise awareness of the risks of OCs exposure and to help establish health policies

  19. Stygofauna of the Canary Islands, 4. Liagoceradocus acutus Andres, 1978, a blind anchihaline amphipod from Lanzarote: redescription, taxonomic status and occurrence

    NARCIS (Netherlands)

    Rondé-Broekhuizen, Brigitte L.M.; Stock, Jan H.

    1987-01-01

    Liagoceradocus acutus Andres, 1978, has been found in different localities on Lanzarote, Canary Islands. A redescription is provided and the taxonomic status of the genus Liagoceradocus is discussed. The species shows sexual dimorphism mainly in the morphology of the propodus of gnathopods 1 and 2,

  20. Return flight to the Canary Islands--the key role of peripheral populations of Afrocanarian blue tits (Aves: Cyanistes teneriffae) in multi-gene reconstructions of colonization pathways.

    Science.gov (United States)

    Päckert, Martin; Martens, Jochen; Hering, Jens; Kvist, Laura; Illera, Juan Carlos

    2013-05-01

    Afrocanarian blue tits (Cyanistes teneriffae) have a scattered distribution on the Canary Islands and on the North African continent. To date, the Canary Islands have been considered the species' main Pleistocene evolutionary center, but their colonization pathways remain uncertain. We set out to reconstruct a dated multi-gene phylogeny and ancestral ranges for Cyanistes tit species including the currently unstudied, peripheral Libyan population of C. t. cyrenaicae. In all reconstructions the most easterly and westerly peripheral populations (in Libya and on La Palma) represented basal offshoots of C. teneriffae. These two peripheral populations shared all four major indels and differed in this respect from all other members of the Afrocanarian core group. The basal split of Afrocanarian blue tits from their European relatives was dated to the early Pliocene. The two ancestral area reconstructions were contradictory and suggested either a Canarian or a North African origin of C. teneriffae - but unambiguously ruled out a continental European ancestral range. We conclude that the peripheral populations of C. teneriffae represent relic lineages of a first faunal interchange, presumably downstream colonization from North Africa to the Canary Islands. Subsequent eastward stepping-stone colonization within the Canarian Archipelago culminated in a very recent late (possibly even post-) Pleistocene back-colonization from the Canary Islands to North Africa.

  1. Some notes on the associated occurrence of the crab Cycloes Cristata (Brullé, 1837) (Brachyura: Calappidae) and two types of Benthic fish in the Canary Islands

    NARCIS (Netherlands)

    Hartog, den J.C.

    1987-01-01

    A concise survey is presented of the species of the crab genus Cycloes De Haan, 1837 (Brachyura: Calappidae). Notes are presented on the associated ocurrence, on shallow sandy bottoms in the Canary Islands (Lanzarote, Gran Canaria), of the eastern Atlantic Cycloes cristata (Brullé, 1837) and the fis

  2. Assessing the origin of unusual organic formations in lava caves from Canary Islands (Spain)

    Science.gov (United States)

    Miller, Ana Z.; de la Rosa, Jose M.; Garcia-Sanchez, Angela M.; Pereira, Manuel F. C.; Jurado, Valme; Fernández, Octavio; Knicker, Heike; Saiz-Jimenez, Cesareo

    2016-04-01

    Lava tubes, like other caves, contain a variety of speleothems formed in the initial stage of a lava tube formation or due to leaching and subsequent precipitation of secondary minerals. Primary and secondary mineral formations in lava caves are mainly composed of silicate minerals, although secondary minerals common in limestone caves have been also reported in this type of caves. In addition, unusual colored deposits have been found on the walls and ceilings of lava tubes, some of them of unknown origin and composition. A brown to black-colored mud-like deposits was observed in "Llano de los Caños" Cave, La Palma Island, Canary Islands, Spain. These black deposits coat the wall and ceiling of the lava tube where sub-horizontal fractures occur. FESEM-EDS, X-ray micro-computed tomography and mineralogical analyses were conducted for morphological, 3D microstructural and compositional characterization of these unusual speleothem samples. These techniques revealed that they are mainly composed of amorphous materials, suggesting an organic carbon composition. Hence, analytical pyrolysis (Py-GC/MS), solid-state 13C Nuclear Magnetic Resonance (NMR) and stable isotope analysis were applied to assess the nature and origin of the black deposits. The combination of these analytical tools permits the identification of specific biomarkers (di- and triterpenoids) for tracing the potential sources of the organic compounds in the speleothems. For comparison purposes, samples from the topsoil and overlaying vegetation were also analyzed. Chromatograms resulting from the Py-GC/MS showed an abundance of polysaccharides, lipids and terpenoids typically derived from the vegetation of the area (Erica arborea). In addition, levoglucosan, polycyclic aromatic hydrocarbons and N-containing heterocyclic compounds were detected. They probably derived from the leaching of charred vegetation resulting from a wildfire occurred in the area in 2012. The lack of the typical pattern of odd

  3. Floating stones off El Hierro, Canary Islands: xenoliths of pre-island sedimentary origin in the early products of the October 2011 eruption

    Directory of Open Access Journals (Sweden)

    V. R. Troll

    2012-03-01

    Full Text Available A submarine eruption started off the south coast of El Hierro, Canary Islands, on 10 October 2011 and continues at the time of this writing (February 2012. In the first days of the event, peculiar eruption products were found floating on the sea surface, drifting for long distances from the eruption site. These specimens, which have in the meantime been termed "restingolites" (after the close-by village of La Restinga, appeared as black volcanic "bombs" that exhibit cores of white and porous pumice-like material. Since their brief appearance, the nature and origin of these "floating stones" has been vigorously debated among researchers, with important implications for the interpretation of the hazard potential of the ongoing eruption. The "restingolites" have been proposed to be either (i juvenile high-silica magma (e.g. rhyolite, (ii remelted magmatic material (trachyte, (iii altered volcanic rock, or (iv reheated hyaloclastites or zeolite from the submarine slopes of El Hierro. Here, we provide evidence that supports yet a different conclusion. We have analysed the textures and compositions of representative "restingolites" and compared the results to previous work on similar rocks found in the Canary Islands. Based on their high-silica content, the lack of igneous trace element signatures, the presence of remnant quartz crystals, jasper fragments and carbonate as well as wollastonite (derived from thermal overprint of carbonate and their relatively high oxygen isotope values, we conclude that "restingolites" are in fact xenoliths from pre-island sedimentary layers that were picked up and heated by the ascending magma, causing them to partially melt and vesiculate. As they are closely resembling pumice in appearance, but are xenolithic in origin, we refer to these rocks as "xeno-pumice". The El Hierro xeno-pumices hence represent messengers from depth that help us to understand the interaction between ascending magma and crustal lithologies

  4. Turbidite record of frequency and source of large volume (>100 km3) Canary Island landslides in the last 1.5 Ma: Implications for landslide triggers and geohazards

    Science.gov (United States)

    Hunt, J. E.; Wynn, R. B.; Talling, P. J.; Masson, D. G.

    2013-07-01

    During the last two decades, numerous studies have focused on resolving the landslide histories of the Canary Islands. Issues surrounding the preservation and dating of onshore and proximal submarine landslide deposits precludes accurate determination of event ages. However, submarine landslides often disaggregate and generate sediment gravity flows. Volcaniclastic turbidites sampled from Madeira Abyssal Plain piston cores represent a record of eight large-volume failures from the Western Canary Islands in the last 1.5 Ma. During this time, there is a mean recurrence rate of 200 ka, while the islands of El Hierro and Tenerife have individual landslide recurrences of 500 ka and 330 ka, respectively. Deposits from the 15 ka El Golfo landslide from El Hierro and 165 ka Icod landslide from Tenerife are examined. This study also identifies potential deposits associated with the Orotava (535 ka), Güímar (850 ka), and Rogues de García landslides (1.2 Ma) from Tenerife, El Julan (540 ka), and El Tiñor (1.05 Ma) landslides from El Hierro, and the Cumbre Nueva landslide (485 ka) from La Palma. Seven of eight landslides occurred during major deglaciations or subsequent interglacial periods, which represent 55% of the time. However, all of the studied landslides occur during or at the end of periods of protracted island volcanism, which generally represent 60% of the island histories. Although climate may precondition failures, it is suggested that volcanism presents a more viable preconditioning and trigger mechanism for Canary Island landslides.

  5. Monitoring the volcanic unrest of El Hierro (Canary Islands) before the onset of the 2011-2012 submarine eruption

    Science.gov (United States)

    López, C.; Blanco, M. J.; Abella, R.; Brenes, B.; Cabrera Rodríguez, V. M.; Casas, B.; Domínguez Cerdeña, I.; Felpeto, A.; de Villalta, M. Fernández; del Fresno, C.; García, O.; García-Arias, M. J.; García-Cañada, L.; Gomis Moreno, A.; González-Alonso, E.; Guzmán Pérez, J.; Iribarren, I.; López-Díaz, R.; Luengo-Oroz, N.; Meletlidis, S.; Moreno, M.; Moure, D.; de Pablo, J. Pereda; Rodero, C.; Romero, E.; Sainz-Maza, S.; Sentre Domingo, M. A.; Torres, P. A.; Trigo, P.; Villasante-Marcos, V.

    2012-07-01

    On 10 October 2011, a submarine volcanic eruption started 2 km south from El Hierro Island (Spain). Since July 2011 a dense multiparametric monitoring network was deployed all over the island by Instituto Geográfico Nacional (IGN). By the time the eruption started, almost 10000 earthquakes had been located and the deformation analyses showed a maximum deformation of more than 5 cm. Earthquake migration from the north to the south of the island and acceleration of seismicity are in good correlation with changes in the deformation pattern as well as with some anomalies in geochemical and geomagnetic parameters. An earthquake of local magnitude 4.3 at 12 km depth (8 October 2011) and shallower seismicity a day after, preceded the onset of the eruption. This is the first time that a volcanic eruption is fully monitored in the Canary Islands. Data recorded during this unrest episode at El Hierro will contribute to understand reawakening of volcanic activity in this region and others of similar characteristics.

  6. Magma displacements under insular volcanic fields, applications to eruption forecasting: El Hierro, Canary Islands, 2011-2013

    Science.gov (United States)

    García, A.; Fernández-Ros, A.; Berrocoso, M.; Marrero, J. M.; Prates, G.; De la Cruz-Reyna, S.; Ortiz, R.

    2014-04-01

    Significant deformations, followed by increased seismicity detected since 2011 July at El Hierro, Canary Islands, Spain, prompted the deployment of additional monitoring equipment. The climax of this unrest was a submarine eruption first detected on 2011 October 10, and located at about 2 km SW of La Restinga, southernmost village of El Hierro Island. The eruption ceased on 2012 March 5, after the volcanic tremor signals persistently weakened through 2012 February. However, the seismic activity did not end with the eruption, as several other seismic crises followed. The seismic episodes presented a characteristic pattern: over a few days the number and magnitude of seismic event increased persistently, culminating in seismic events severe enough to be felt all over the island. Those crises occurred in 2011 November, 2012 June and September, 2012 December to 2013 January and in 2013 March-April. In all cases the seismic unrest was preceded by significant deformations measured on the island's surface that continued during the whole episode. Analysis of the available GPS and seismic data suggests that several magma displacement processes occurred at depth from the beginning of the unrest. The first main magma movement or `injection' culminated with the 2011 October submarine eruption. A model combining the geometry of the magma injection process and the variations in seismic energy release has allowed successful forecasting of the new-vent opening.

  7. Morphometric interpretation of the northwest and southeast slopes of Tenerife, Canary Islands

    Science.gov (United States)

    1997-01-01

    Both the northwest and southeast slopes of Tenerife, Canary Islands, owe their morphology to catastrophic sediment failures. An area of 4100 km2 and a volume of about 2362 km3 were involved in the failure. A 100- to 600-m-high scarp on the upper slope separates the sediment failures in the Orotova and Icod de los Vinos Valleys on the northwest coast from those on the slope. A similar (700 m high) scarp also separates the failures on the southeast slope from the failure in Güimar Valley on land. The sediment failure off Las Bandas Del Sur volcanic fan does not have any land counterparts and was the result of the failure of the front (1700 m high) of this depocenter; two generations of debris flows are mappable off this depocenter. We infer that the slopes off Orotova, Icod, and Güimar represent the front of the debris avalanche and/or creep deposits that were created during the formation of the valleys. Downslope from the debris avalanche fronts are irregular surfaced masses extending to the base of the slope. The front may define the contact between the more dense deposits onshore and upper slope and the more fluid deposits on the lower slope. Incised on the debris avalanche on the northwest lower slope are three channeled debris flows grading seaward into turbidites. Only one of these channels occurs on the southeast slope. The breakaway surface of these sediment failures was the front of the debris avalanches and/or creep. We ascribe the failure of this front mainly to its rapid buildup, although groundwater sapping also may have contributed to its failure. On the southeast slope, movement along the northeast trending fault between Gran Canaria and Tenerife also may have been a contributing factor to the failure of the front. The debris flow deposits triggered by the failure of the sediment front on the northwest slope are characterized by ridges formed either by pressure between flows moving at different velocities or by scouring; at least one volcanic edifice

  8. Influence of management practices on C stabilization pathways in agricultural volcanic ash soils (Canary Islands, Spain)

    Science.gov (United States)

    Hernandez, Zulimar; María Álvarez, Ana; Carral, Pilar; de Figueiredo, Tomas; Almendros, Gonzalo

    2014-05-01

    Although C stabilization mechanisms in agricultural soils are still controversial [1], a series of overlapped pathways has been suggested [2] such as: i) insolubilization of low molecular weight precursors of soil organic matter (SOM) with reactive minerals through physical and chemical bonding, ii) selective accumulation of biosynthetic substances which are recalcitrant because of its inherent chemical composition, and iii) preservation and furter diagenetic transformation of particulate SOM entrapped within resistant microaggregates, where diffusion of soil enzymes is largely hampered. In some environments where carbohydrate and N compounds are not readily biodegraded, e.g., with water saturated micropores, an ill-known C stabilization pathway may involve the formation of Maillard's reaction products [3]. In all cases, these pathways converge in the formation of recalcitrant macromolecular substances, sharing several properties with the humic acid (HA) fraction [4]. In template forests, the selective preservation and further microbial reworking of plant biomass has been identified as a prevailing mechanism in the accumulation of recalcitrant SOM forms [5]. However, in volcanic ash soils with intense organomineral interactions, condensation reactions of low molecular weight precursors with short-range minerals may be the main mechanism [6]. In order to shed some light about the effect of agricultural management on soil C stabilization processes on volcanic ash soils, the chemical composition of HA and some structural proxies of SOM informing on its origin and potential resistance to biodegradation, were examined in 30 soils from Canary Islands (Spain) by visible, infrared (IR) and 13C nuclear magnetic resonance (NMR) spectroscopies, elementary analysis and pyrolytic techniques. The results of multivariate treatments, suggested at least three simultaneous C stabilization biogeochemical trends: i) diagenetic alteration of plant biomacromolecules in soils receiving

  9. International migration, transnational links and ethnic economy. The case of the Indostanic community in the Canary Islands

    Directory of Open Access Journals (Sweden)

    Ana María López Sala

    2007-10-01

    Full Text Available The Sindhi diaspora is one of the most extensive and influential of Asian commercial diasporas. Its expansion commenced in the 15th century, but it grew significantly in the second half of the 19th century and in the middle of the 20th. The aim of this article is to describe the Sindhis’ settling and commercial activity on the Canary Islands one of the establishing points of the network and to produce a critical reflection of some of the alternative guidelines for economic integration in places where, as in this case, the territory is presented as a space of opportunities for achieving economic objectives. Such an analysis must consider the make-up and dynamic of this transnational network through which information, capital, goods and people circulate.

  10. Stomoxys calcitrans as possible vector of Trypanosoma evansi among camels in an affected area of the Canary Islands, Spain

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    Noé Francisco Rodríguez

    2014-07-01

    Full Text Available Introduction Trypanosoma evansi was first identified in the Canary Islands in 1997, and is still present in a small area of the Archipelago. To date, the disease has exclusively affected camel herds, and has not been detected in any other animal hosts. However potential vectors of Trypanosoma evansi must be identified. Methods One Nzi trap was placed on a camel farm located in the infected area for a period of one year. Results Two thousand five hundred and five insects were trapped, of which Stomoxys calcitrans was the sole hematophagous vector captured. Conclusions Stomoxys calcitrans could be exclusively responsible for the transmission of Trypanosoma evansi among camels in the surveyed area, as other species do not seem to be infected by S. calcitrans in the presence of camels.

  11. Planck Intermediate Results. XXXVI. Optical identification and redshifts of Planck SZ sources with telescopes in the Canary Islands Observatories

    CERN Document Server

    Ade, P A R; Arnaud, M; Ashdown, M; Aumont, J; Baccigalupi, C; Banday, A J; Barreiro, R B; Barrena, R; Bartolo, N; Battaner, E; Benabed, K; Benoit-Lévy, A; Bernard, J -P; Bersanelli, M; Bielewicz, P; Bikmaev, I; Böhringer, H; Bonaldi, A; Bonavera, L; Bond, J R; Borrill, J; Bouchet, F R; Burenin, R; Burigana, C; Calabrese, E; Cardoso, J -F; Catalano, A; Chamballu, A; Chary, R -R; Chiang, H C; Chon, G; Christensen, P R; Clements, D L; Colombo, L P L; Combet, C; Comis, B; Crill, B P; Curto, A; Cuttaia, F; Dahle, H; Danese, L; Davies, R D; Davis, R J; de Bernardis, P; de Rosa, A; de Zotti, G; Delabrouille, J; Diego, J M; Dole, H; Donzelli, S; Doré, O; Douspis, M; Dupac, X; Efstathiou, G; Elsner, F; Enßlin, T A; Eriksen, H K; Ferragamo, A; Finelli, F; Forni, O; Frailis, M; Fraisse, A A; Franceschi, E; Fromenteau, S; Galeotta, S; Galli, S; Ganga, K; Génova-Santos, R T; Giard, M; Gjerløw, E; González-Nuevo, J; Górski, K M; Gruppuso, A; Hansen, F K; Harrison, D L; Hempel, A; Hernández-Monteagudo, C; Herranz, D; Hildebrandt, S R; Hivon, E; Hornstrup, A; Hovest, W; Huffenberger, K M; Hurier, G; Jaffe, T R; Keihänen, E; Keskitalo, R; Khamitov, I; Kisner, T S; Knoche, J; Kunz, M; Kurki-Suonio, H; Lamarre, J -M; Lasenby, A; Lattanzi, M; Lawrence, C R; Leonardi, R; León-Tavares, J; Levrier, F; Lietzen, H; Liguori, M; Lilje, P B; Linden-Vørnle, M; López-Caniego, M; Lubin, P M; Macías-Pérez, J F; Maffei, B; Maino, D; Mandolesi, N; Maris, M; Martin, P G; Martínez-González, E; Masi, S; Matarrese, S; McGehee, P; Melchiorri, A; Mennella, A; Migliaccio, M; Miville-Deschênes, M -A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Natoli, P; Novikov, D; Novikov, I; Oxborrow, C A; Pagano, L; Pajot, F; Paoletti, D; Pasian, F; Perdereau, O; Pettorino, V; Piacentini, F; Piat, M; Pierpaoli, E; Plaszczynski, S; Pointecouteau, E; Polenta, G; Pratt, G W; Prunet, S; Puget, J -L; Rachen, J P; Rebolo, R; Reinecke, M; Remazeilles, M; Renault, C; Renzi, A; Ristorcelli, I; Rocha, G; Rosset, C; Rossetti, M; Roudier, G; Rubiño-Martín, J A; Rusholme, B; Sandri, M; Santos, D; Savelainen, M; Savini, G; Scott, D; Stolyarov, V; Streblyanska, A; Sudiwala, R; Sunyaev, R; Suur-Uski, A -S; Sygnet, J -F; Terenzi, L; Toffolatti, L; Tomasi, M; Tramonte, D; Tristram, M; Tucci, M; Valenziano, L; Valiviita, J; Van Tent, B; Vielva, P; Villa, F; Wade, L A; Wandelt, B D; Wehus, I K; Yvon, D; Zacchei, A; Zonca, A

    2015-01-01

    We present the results of approximately three years of observations of Planck Sunyaev-Zeldovich (SZ) sources with telescopes at the Canary Islands observatories, as part of the general optical follow-up programme undertaken by the Planck collaboration. In total, 78 SZ sources are discussed. Deep imaging observations were obtained for most of those sources; spectroscopic observations in either in long-slit or multi-object modes were obtained for many. We found optical counterparts for 73 of the 78 candidates. This sample includes 53 spectroscopic redshifts determinations, 20 of them obtained with a multi-object spectroscopic mode. The sample contains new redshifts for 27 Planck clusters that were not included in the first Planck SZ source catalogue (PSZ1).

  12. K/Ar ages, magnetic stratigraphy and morphological evolution of La Gomera: implications for the Canary Islands hotspot evolution.

    Science.gov (United States)

    Paris, R.; Guillou, H.; Carracedo, J. C.; Pérez Torrado, F. J.

    2003-04-01

    The Canary Islands are a group of seven volcanic islands, 100-700 km west of the Sahara continental margin. The spatial and chronological evolution of the canarian volcanism, from east to west, is due to the progression of the slow-moving african plate on a hotspot. La Gomera is located between the western shield-growing stage islands (La Palma, 1,7 Ma and El Hierro, 1,1 Ma) and the central "rejuvaneted stage" islands (Tenerife, 11,9 Ma and Gran Canaria, 14,5 Ma). After 23 K-Ar ages and paleomagnetism datas, we determine the main volcanic phases of La Gomera : (1) the submarine shield volcano (> 9,5 Ma), (2) the first subaeriel shield volcano (9,43-7,36 Ma), (3) the Vallehermoso stratovolcan, (4) the peripheral "planèzes" and domes forming series (6,67-1,94 Ma) and the Garajonay horizontal series (5,42-4,25 Ma). The stratovolcano and the horizontal series fill a 10 km wide depression that is supposed to be a giant landslide embayment. The scarps of this landslide correspond to the main discontinuity in the island structure. After 4 M.y. of very scarce volcanism, the whole structure of La Gomera is in relief inversion, with a radial pattern of deep barrancos. The erosion rates are lower during the hiatus (< 0,2 m/ka) than during the shield stage (0,2-0,9 m/ka), pointing out the fact that the volcanic construction rates and the erosion rates are strongly correlated. La Gomera is one of the best example of a hiatus stage of hotspot evolution. The volcanic load La Gomera and Tenerife may have delayed the western islands volcanism, favouring a dual-line.

  13. Under the volcano: phylogeography and evolution of the cave-dwelling Palmorchestia hypogaea (Amphipoda, Crustacea at La Palma (Canary Islands

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    Oromí Pedro

    2008-01-01

    Full Text Available Abstract Background The amphipod crustacean Palmorchestia hypogaea occurs only in La Palma (Canary Islands and is one of the few terrestrial amphipods in the world that have adapted to a strictly troglobitic life in volcanic cave habitats. A surface-dwelling closely related species (Palmorchestia epigaea lives in the humid laurel forest on the same island. Previous studies have suggested that an ancestral littoral Orchestia species colonized the humid forests of La Palma and that subsequent drought episodes in the Canaries reduced the distribution of P. epigaea favouring the colonization of lava tubes through an adaptive shift. This was followed by dispersal via the hypogean crevicular system. Results P. hypogaea and P. epigaea did not form reciprocally monophyletic mitochondrial DNA clades. They showed geographically highly structured and genetically divergent populations with current gene flow limited to geographically close surface locations. Coalescence times using Bayesian estimations assuming a non-correlated relaxed clock with a normal prior distribution of the age of La Palma, together with the lack of association of habitat type with ancestral and recent haplotypes, suggest that their adaptation to cave life is relatively ancient. Conclusion The data gathered here provide evidence for multiple invasions of the volcanic cave systems that have acted as refuges. A re-evaluation of the taxonomic status of the extant species of Palmorchestia is needed, as the division of the two species by habitat and ecology is unnatural. The information obtained here, and that from previous studies on hypogean fauna, shows the importance of factors such as the uncoupling of morphological and genetic evolution, the role of climatic change and regressive evolution as key processes in leading to subterranean biodiversity.

  14. Aquifer Recharge Estimation through Atmospheric Chloride Mass Balance at Las Cañadas Caldera, Tenerife, Canary Islands, Spain

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    Rayco Marrero-Diaz

    2015-05-01

    Full Text Available The atmospheric chloride mass balance (CMB method was used to estimate net aquifer recharge in Las Cañadas Caldera, an endorheic summit aquifer area about 2000 m a.s.l. with negligible surface runoff, which hosts the largest freshwater reserve in Tenerife Island, Canary Islands, Spain. The wet hydrological year 2005–2006 was selected to compare yearly atmospheric chloride bulk deposition and average chloride content in recharge water just above the water table, both deduced from periodical sampling. The potential contribution of chloride to groundwater from endogenous HCl gas may invalidate the CMB method. The chloride-to-bromide molar ratio was an efficient tracer used to select recharge water samples having atmospheric origin of chloride. Yearly net aquifer recharge was 631 mm year−1, i.e., 69% of yearly precipitation. This result is in agreement with potential aquifer recharge estimated through an independent lumped-parameter rainfall-runoff model operated by the Insular Water Council of Tenerife. This paper illustrates basic procedures and routines to use the CMB method for aquifer recharge in active volcanic oceanic islands having sparse-data coverage and groundwater receiving contribution of endogenous halides.

  15. Groundwater flow in a volcanic-sedimentary coastal aquifer: Telde area, Gran Canaria, Canary Islands, Spain

    Science.gov (United States)

    Cabrera, M. C.; Custodio, E.

    Groundwater conditions in a 75- km2 coastal area around the town of Telde in eastern Gran Canaria island have been studied. Pliocene to Recent volcanic materials are found, with an intercalated detrital formation (LPDF), which is a characteristic of the area. Groundwater development has become intensive since the 1950s, mostly for intensive agricultural irrigation and municipal water supply. The LPDF is one order of magnitude more transmissive and permeable than the underlying Phonolitic Formation when median values are compared (150 and 15 m2 day-1 5 and 0.5 m day-1, respectively). These two formations are highly heterogeneous and the ranges of expected well productivities partly overlap. The overlying recent basalts constituted a good aquifer several decades ago but now are mostly drained, except in the southern areas. Average values of drainable porosity (specific yield) seem to be about 0.03 to 0.04, or higher. Groundwater development has produced a conspicuous strip where the watertable has been drawn down as much as 40 m in 20 years, although the inland watertable elevation is much less affected. Groundwater reserve depletion contributes only about 5% of ed water, and more than 60% of this is transmitted from inland areas. Groundwater discharge into the sea may still be significant, perhaps 30% of total inflow to the area is discharged to the sea although this value is very uncertain. Les conditions de gisement de l'eau souterraine d'une région de 75 km2 de la côte Est de l'île de la Grande Canarie (archipel des Canaries), dans le secteur de Telde, ont été étudiées, en utilisant seulement les données fournies par les puits d'exploitation existants. Les matériaux volcaniques, d'âge Pliocène à sub-actuel, sont séparés par une formation détritique (FDLP), qui constitue la principale singularité de cette région. L'exploitation de l'eau souterraine est devenue intensive à partir de 1950, principalement pour des besoins d'irrigation (agriculture

  16. Spiders on a Hot Volcanic Roof: Colonisation Pathways and Phylogeography of the Canary Islands Endemic Trap-Door Spider Titanidiops canariensis (Araneae, Idiopidae.

    Directory of Open Access Journals (Sweden)

    Vera Opatova

    Full Text Available Studies conducted on volcanic islands have greatly contributed to our current understanding of how organisms diversify. The Canary Islands archipelago, located northwest of the coast of northern Africa, harbours a large number of endemic taxa. Because of their low vagility, mygalomorph spiders are usually absent from oceanic islands. The spider Titanidiops canariensis, which inhabits the easternmost islands of the archipelago, constitutes an exception to this rule. Here, we use a multi-locus approach that combines three mitochondrial and four nuclear genes to investigate the origins and phylogeography of this remarkable trap-door spider. We provide a timeframe for the colonisation of the Canary Islands using two alternative approaches: concatenation and species tree inference in a Bayesian relaxed clock framework. Additionally, we investigate the existence of cryptic species on the islands by means of a Bayesian multi-locus species delimitation method. Our results indicate that T. canariensis colonised the Canary Islands once, most likely during the Miocene, although discrepancies between the timeframes from different approaches make the exact timing uncertain. A complex evolutionary history for the species in the archipelago is revealed, which involves two independent colonisations of Fuerteventura from the ancestral range of T. canariensis in northern Lanzarote and a possible back colonisation of southern Lanzarote. The data further corroborate a previously proposed volcanic refugium, highlighting the impact of the dynamic volcanic history of the island on the phylogeographic patterns of the endemic taxa. T. canariensis includes at least two different species, one inhabiting the Jandia peninsula and central Fuerteventura and one spanning from central Fuerteventura to Lanzarote. Our data suggest that the extant northern African Titanidiops lineages may have expanded to the region after the islands were colonised and, hence, are not the source

  17. Uranium-series ages of corals, sea level history, and palaeozoogeography, Canary Islands, Spain: an exploratory study for two Quaternary interglacial periods

    Science.gov (United States)

    Muhs, Daniel R.; Meco, Joaquín; Simmons, Kathleen R.

    2014-01-01

    We present the first U-series ages of corals from emergent marine deposits on the Canary Islands. Deposits at + 20 m are 481 ± 39 ka, possibly correlative to marine isotope stage (or MIS) 11, while those at + 12 and + 8 m are 120.5 ± 0.8 ka and 130.2 ± 0.8 ka, respectively, correlative to MIS 5.5. The age, elevations, and uplift rates derived from MIS 5.5 deposits on the Canary Islands allow calculations of hypothetical palaeo-sea levels during the MIS 11 high sea stand. Estimates indicate that the MIS 11 high sea stand likely was at least + 9 m (relative to present sea level) and could have been as high as + 24 m. The most conservative estimates of palaeo-sea level during MIS 11 would require an ice mass loss equivalent to all of the modern Greenland and West Antarctic ice sheets; the more extreme estimates would require additional ice mass loss from the East Antarctic ice sheet. Extralimital southern species of mollusks, found in both MIS 11 and MIS 5.5 deposits on the Canary Islands, imply warmer-than-modern sea surface temperatures during at least a part of MIS 11 and much warmer sea surface temperatures during at least a part of MIS 5.5. Both MIS 11 and MIS 5.5 marine deposits on the Canary Islands contain extralimital northern species of mollusks as well, indicating cooler-than-present waters at times during these interglacial periods. We hypothesize that the co-occurrence of extralimital southern and northern species of marine invertebrates in the fossil record of the Canary Islands reflects its geographic location with respect to major synoptic-scale controls on climate and ocean currents. Previous interglacials may have been characterized by early, insolation-forced warming, along with northward migration of the intertropical convergence zone (ITCZ), accompanied by weakened trade winds and diminished upwelling. This allowed the arrival of extralimital southern taxa from the tropical Senegalese faunal province. During later parts of the MIS 11 and 5

  18. Ancient DNA of the extinct lava shearwater (Puffinus olsoni from the Canary Islands reveals incipient differentiation within the P. puffinus complex.

    Directory of Open Access Journals (Sweden)

    Oscar Ramirez

    Full Text Available BACKGROUND: The loss of species during the Holocene was, dramatically more important on islands than on continents. Seabirds from islands are very vulnerable to human-induced alterations such as habitat destruction, hunting and exotic predators. For example, in the genus Puffinus (family Procellariidae the extinction of at least five species has been recorded during the Holocene, two of them coming from the Canary Islands. METHODOLOGY/PRINCIPAL FINDINGS: We used bones of the two extinct Canary shearwaters (P. olsoni and P. holeae to obtain genetic data, for use in providing insights into the differentiation process within the genus Puffinus. Although mitochondrial DNA (mtDNA cytochrome b sequences were successfully retrieved from four Holocene specimens of the extinct Lava shearwater (P. olsoni from Fuerteventura (Canary Islands, the P. holeae specimens yielded no DNA. Only one haplotype was detected in P. olsoni, suggesting a low genetic diversity within this species. CONCLUSIONS: The phylogenetic analyses based on the DNA data reveal that: (i the "Puffinus puffinus complex", an assemblage of species defined using osteological characteristics (P. puffinus, P. olsoni, P. mauretanicus, P. yelkouan and probably P. holeae, shows unresolved phylogenetic relationships; (ii despite the differences in body size and proportions, P. olsoni and the extant P. puffinus are sister species. Several hypotheses can be considered to explain the incipient differentiation between P. olsoni and P. puffinus.

  19. Development and recent activity of the San Andrés landslide on El Hierro, Canary Islands, Spain

    Science.gov (United States)

    Klimeš, Jan; Yepes, Jorge; Becerril, Laura; Kusák, Michal; Galindo, Inés; Blahut, Jan

    2016-05-01

    Extremely voluminous landslides with a long run-out (also known as megalandslides) on oceanic volcanic islands are infrequent denudational processes on such islands. At the same time, they represent a major geological hazard that must be looked into to avoid negative consequences for the inhabitants of these islands. Their occurrence can be related to periods of intense seismo-volcanic activity, similar to that which occurred on El Hierro Island over 2011-2012. Landslides on volcanic islands are studied using onshore and offshore geological, geophysical and geomorphological records, considering their unique triggering conditions (e.g. lava intrusions, eruptive vents, magma chamber collapses). Previous work has pointed out similarities between specific cases of landslides on volcanic islands and deep-seated gravitational slope deformations (DSGSDs) which are typical in high mountain settings. Nevertheless, the methodological approaches and concepts used to investigate DSGSDs are not commonly applied on volcanic islands studies, even though their use may provide new information about the development stage, recent movements and future hazards. Therefore, this approach for studying the San Andrés landslide (SAL) on El Hierro (Canary Islands) has been developed applying a detailed morphological field mapping, an interpretation of digital elevation models, structural measurements, kinematic testing, and a precise movement monitoring system. The acquired information revealed a strong structural influence on the landslide morphology and the presence of sets of weakened planes acting as the sliding surfaces of the SAL or secondary landslides within its body. The presence of secondary landslides, deep erosive gullies, coastal cliffs and high on-shore relative relief also suggests a high susceptibility to future landslide movement. Direct monitoring on the landslide scarps and the slip plane, performed between February 2013 and July 2014, using an automated optical

  20. A combined paleomagnetic/dating investigation of the upper Jaramillo transition from a volcanic section at Tenerife (Canary Islands)

    Science.gov (United States)

    Kissel, C.; Guillou, H.; Laj, C.; Carracedo, J. C.; Perez-Torrado, F.; Wandres, C.; Rodriguez-Gonzalez, A.; Nomade, S.

    2014-11-01

    A coupled paleomagnetic/dating investigation has been conducted on a sequence of 25 successive lava flows, emplaced during the upper transition of the Jaramillo subchron in Tenerife, Canary Islands. This sequence is located along the western wall of the Güímar collapse scar, in the south central part of the island. Nine flows distributed throughout this sequence were dated using unspiked K/Ar and 40Ar/39Ar methods. They bracket the section between 1009±22 ka and 971±21 ka (2σ). A first group of 8 flows at the bottom of the sequence is characterized by normal polarity with paleointensity values of the order of present-day field intensity in the Canary Islands. The virtual geomagnetic poles (VGP) of these 8 flows describe a short loop at high latitudes. Seven overlying flows are transitional in directions and dated between 991±14 ka and 1002±11 ka consistently with published ages of the upper Jaramillo reversal. This second group of flows is characterized by low paleointensity values (around 8-12 μT) that are less than 30% of the present dipole value in Tenerife. The VGPs of the first two transitional flows lie over northeastern Pacific whereas the five following transitional flows have all negative inclinations and their VGPs lie initially over East Antarctica, then describe a northward loop almost reaching New Zealand. The final group of ten flows yield intensities varying between 20 and 35 μT and VGPs close to the southern pole with two of them describing a small amplitude second loop to southeastern Pacific. Assuming a constant extrusion rate as a very first approximation, the distribution of the obtained ages suggests a duration of 7.6±5.6 ka for the transitional interval. The obtained transitional positions of VGPs are consistent with the path reported for the same reversal from North Atlantic sediments but are different from the only other volcanic record from Tahiti. The intensity low characterizing the transitional interval remains the best tie

  1. Genetic study of the population of Tenerife (Canary Islands, Spain): protein markers and review of classical polymorphisms.

    Science.gov (United States)

    Moral, P; Esteban, E; Vives, S; Valveny, N; Toja, D I; Gonzalez-Reimers, E

    1997-03-01

    Data on six protein polymorphisms (19 alleles) from the human population of Tenerife are presented and discussed along with other classical markers in relation to the origin of the Canarians. Genetic influences from three population groups were considered: the Iberians, and the Berbers and non-Berbers (Arabs) from north Africa. The systems examined show the Tenerife population lies within the limits of variation described for various Iberian groups, with a slight tendency towards the characteristics of north African populations. When blood groups, red cell enzymes and serum protein data were considered, the similarity of the Canary population to Iberians seems strengthened (70% estimated contribution of Iberian peninsula genes to the present-day Canarian pool), while some relation with north African groups is shown. Genetic distances between Canarians and Arabs and Canarians and Berbers are lower than those between the two north African groups, indicating a relative and comparable contribution of each to the present-day gene pool of the Canarian population. The Arab contribution could be attributable to the slaves who were introduced to these islands after the conquest in the 15th century, while the Berber contribution could be the remnants of the extinct aboriginal peoples of the islands (Guanches) or a more recent immigration due to slavery. Genetic data do not allow us to distinguish between these two possibilities.

  2. How to make a European integrated market in small and isolated electricity systems? The case of the Canary Islands

    Energy Technology Data Exchange (ETDEWEB)

    Perez, Yannick [Universite de Paris-Sud 11, Groupe Reseaux Jean-Monnet-ADIS, 27 Avenue Lombart Bureau C 309, 92260 Fontenay aux Roses Cedex (France); Ramos Real, Francisco Javier [Departamento de Analisis Economico e Instituto de Desarrollo Regional, Camino de La Hornera s/n, Campus de Guajara, Universidad de La Laguna, 38071 La Laguna. SC de Tenerife (Spain)

    2008-11-15

    This paper presents a geographic dimension not often studied in the dynamics of creating an internal market for electricity within the European Union, namely the case of small European electricity systems like those found on the Greek islands of Cyprus and Crete. Our question, then, is how to achieve a suitable internal market for electricity in small and isolated systems. To address this issue, we identify the main problems to be overcome by introducing a methodology in which the Canary Islands experience is taken as a case study for understanding the challenges in creating an 'EU-like market for electricity'. Our results show that the design of the vertical industrial structure and the figure of the grid operator and its attributes are key features for the proper operation of any electrical system. We also stress the minor roles of other possible options to achieve this EU-compatible market by highlighting first, in the wholesale market, the call-for-tender solution to introduce more generation and the risk of using safety requirements as barriers to entry in these small markets, and second, in the supply activities, the potential problems of an improperly regulated tariff scheme. (author)

  3. The role of tourist destination in international students’ choice of academic center: the case of erasmus programme in the Canary Islands

    OpenAIRE

    Francisco J. García\\u2011Rodríguez; Javier Mendoza Jiménez

    2015-01-01

    The study measures the importance of the university and the tourist destination factors in the international students´ choice of placement for their studies and their further satisfaction. Using a sample from the Erasmus Exchange Programme in the Canary Islands, one of the main European tourist destinations, the results show the potential that academic tourism could have for the host destination and in particular, the importance of the attraction factors linked to the destination rather than ...

  4. Salmonellosis and charter tourism: epidemiology and trends of imported human cases to Norway from the Canary Islands and Thailand, 1994-2008.

    Science.gov (United States)

    Emberland, K E; Nygård, K; Aavitsland, P

    2012-09-01

    More than 70% of reported human Salmonella infections in Norway are infected abroad. The Canary Islands and Thailand are two of the most popular charter tourist destinations for Norwegians. Using surveillance data for the years 1994-2008, and denominator data on travel to the Canary Islands 2000-2008 and to Thailand 1997-2008, we present the epidemiology and trends of Salmonella infections in Norwegian tourists to these destinations. We found a declining trend in risk of salmonellosis in tourists returning from the Canary Islands, and a change in serovar distribution in travellers to Thailand with more S. Enteritidis infections, similar to that observed in Western European countries. The use of denominator data is important when studying risk of travel-related disease, as surveillance data tend to reflect travel activity more than the risk. Infections among tourists do not always affect the local residents and therefore may not be detected by local public health authorities. Sharing knowledge on the epidemiology of infections in tourists could be useful for observation of changes in trends in the countries visited, and in future outbreak investigations.

  5. "Canary Islands, a volcanic window in the Atlantic Ocean": a 7 year effort of public awareness on volcano hazards and risk management

    Science.gov (United States)

    Rodríguez, Fátima; Calvo, David; Pérez, Nemesio M.; Padrón, Eleazar; Melián, Gladys; Padilla, Germán; Barrancos, José; Hernández, Pedro A.; Asensio-Ramos, María; Alonso, Mar

    2016-04-01

    "Canary Islands: A volcanic window in the Atlantic Ocean" is an educational program born from the need to inform and educate citizens residing in the Canary Islands on the various hazards associated to volcanic phenomena. The Canary Islands is the only territory of Spain that hosts active volcanism, as is shown by the 16 historical eruptions that have occurred throughout this territory, being the last one a submarine eruption taking place on October 12, 2011, offshore El Hierro Island. In the last 7 years, ITER as well as INVOLCAN have been performing an educative program focused on educating to the population about the benefits of a volcanic territory, volcanic hazards, how to reduce volcanic risk and the management of volcanic risk in the Canary Islands. "Canary Islands: A volcanic window in the Atlantic Ocean" consists of three units, the first two dedicated to the IAVCEI/UNESCO videos "Understanding Volcanic Hazards" and "Reducing Volcanic Risk" and the third one dedicated to the management of volcanic risk in the Canary Islands, as well as some other aspects of the volcanic phenomena. Generally the three units are shown consecutively on Tuesday, Wednesday and Thursday. This educative program has been roaming all around the 88 municipalities of the archipelago since this initiative started in 2008. The total number of attendees since then amounts to 18,911 people. The increase of assistance was constant until 2011, with annual percentages of 7.8, 17.1 and 20.9 respectively, regarding to ratio assistant/municipality. Despite the heterogeneity of the audience, the main audience is related to aged people of 45 years and older. This could be related to the memories of the recent eruptions occurred at La Palma Island in 1949 and 1971. It is important to point out that many of those people attending the educative program are representatives of local government (i.e. civil protection). Regarding the interest of the audience, the educational program attendees have

  6. Relative and probabilistic non linear relocation of the seismicity of El Hierro (Canary Islands, Spain): Implications for the 2011-2012 eruption.

    Science.gov (United States)

    Diaz-Moreno, Alejandro; Garcia-Yeguas, Araceli; De Angelis, Silvio; Prudencio, Janire; Ibañez, Jesus M.; Morales, José; Koulakov, Ivan

    2014-05-01

    El Hierro Island (Canary Islands, SPAIN) has recently attracted the interest of the international volcanological community. During a prolonged period of seismic and volcanic unrest, between July 2011 and April 2013, the local seismic network recorded more than 15,000 earthquakes accompanied by a submarine eruption. In this study we present an exhaustive relocation analysis of the original seismic catalog using two well established methods double-difference relative relocation (HypoDD), and probalistic non-linear location (NLLoc). Our relocations are based on 3D velocity models that were obtained from an active-source tomography experiment in the Canary Islands. The relocations constrain the spatial and temporal distribution of seismicity, and help to shed light on the patterns of stress propagation, and areas of crustal weakness under the island. The results show that the seismicity each of unrest recorded during this period is located within a small region close to the center of the island and located around 12 to 14 km depth. Then, the seismicity migrates away from the island. We confirm the presence of a high-velocity block centered underneath El Hierro (up to 15km depth) observed by other authors. This block may represent a barrier to magma propagation and it corresponds to the location of the bulk of seismicity at the beginning of each phase.

  7. CO2-SO3-rich (carbonate-sulfate) melt/fluids in the lithosphere beneath El Hierro, Canary Islands.

    Science.gov (United States)

    Oglialoro, E.; Ferrando, S.; Malaspina, N.; Villa, I. M.; Frezzotti, M. L.

    2015-12-01

    Mantle xenoliths from the island of El Hierro, the youngest of the Canary Islands, have been studied to characterize fluxes of carbon in the lithosphere of an OIB volcanism region. Fifteen xenoliths (4-10 cm in diameter) were collected in a rift lava flow (15-41 ka) at a new xenolith locality in El Julan cliff (S-SW of the island). Peridotites consist of protogranular to porphyroblastic spinel harzburgites, lherzolites, and subordinate dunites. One spinel clinopyroxenite, and one olivine-websterite were also analyzed. Ultramafic xenoliths were classified as HEXO (harzburgite and dunite with exsolved orthopyroxene), HLCO (harzburgite and lherzolite containing orthopyroxene without visible exsolution lamellae), and HTR (transitional harzburgite with exsolved orthopyroxene porphyroclasts, and poikilitic orthopyroxene) following [1]. While HLCO and HTR peridotites contain mostly CO2 fluid inclusions, HEXO peridotites preserve an early association of melt/fluid inclusions containing dominantly carbonate/sulfate/silicate glass, evolving to carbonate/sulfate/phosphate/spinel aggregates, with exsolved CO2 (± carbonates, anhydrite and H2O). Chemical and Raman analyses identify dolomite, Mg-calcite, anhydrite, sulfohalite [Na6(SO4)2FCl] (± other anhydrous and hydrous alkali-sulfates), apatite, and Cr-spinel in the inclusions. Sulfides are noticeably absent. The microstructure and chemical composition of the metasomatic fluids indicate that the peridotites were infiltrated by a carbonate-sulfate-silicate melt/fluid enriched in CO2, H2O, and P. A mantle origin for this fluid is supported by high densities of CO2inclusions (> 1g/cm3), determined by Raman microspectroscopy and cross-checked by microthermometry. Consequently, El Julan peridotites provide the first evidence for liberating oxidized C and S fluxes from the Earth lithosphere in an OIB source region, and suggest that oxidation of sulfide to sulfate can occur during small-degree partial melting of the upper mantle

  8. Evidence from acoustic imaging for submarine volcanic activity in 2012 off the west coast of El Hierro (Canary Islands, Spain)

    Science.gov (United States)

    Pérez, Nemesio M.; Somoza, Luis; Hernández, Pedro A.; de Vallejo, Luis González; León, Ricardo; Sagiya, Takeshi; Biain, Ander; González, Francisco J.; Medialdea, Teresa; Barrancos, José; Ibáñez, Jesús; Sumino, Hirochika; Nogami, Kenji; Romero, Carmen

    2014-12-01

    We report precursory geophysical, geodetic, and geochemical signatures of a new submarine volcanic activity observed off the western coast of El Hierro, Canary Islands. Submarine manifestation of this activity has been revealed through acoustic imaging of submarine plumes detected on the 20-kHz chirp parasound subbottom profiler (TOPAS PS18) mounted aboard the Spanish RV Hespérides on June 28, 2012. Five distinct "filament-shaped" acoustic plumes emanating from the flanks of mounds have been recognized at water depth between 64 and 88 m on a submarine platform located NW El Hierro. These plumes were well imaged on TOPAS profiles as "flares" of high acoustic contrast of impedance within the water column. Moreover, visible plumes composed of white rafts floating on the sea surface and sourcing from the location of the submarine plumes were reported by aerial photographs on July 3, 2012, 5 days after acoustic plumes were recorded. In addition, several geophysical and geochemical data support the fact that these submarine vents were preceded by several precursory signatures: (i) a sharp increase of the seismic energy release and the number of daily earthquakes of magnitude ≥2.5 on June 25, 2012, (ii) significant vertical and horizontal displacements observed at the Canary Islands GPS network (Nagoya University-ITER-GRAFCAN) with uplifts up to 3 cm from June 25 to 26, 2012, (iii) an anomalous increase of the soil gas radon activity, from the end of April until the beginning of June reaching peak values of 2.7 kBq/m3 on June 3, 2012, and (iv) observed positive peak in the air-corrected value of 3He/4He ratio monitored in ground waters (8.5 atmospheric 3He/4He ratio ( R A)) at the northwestern El Hierro on June 16, 2012. Combining these submarine and subaerial information, we suggest these plumes are the consequence of submarine vents exhaling volcanic gas mixed with fine ash as consequence of an event of rapid rise of volatile-rich magma beneath the NW submarine ridge

  9. On the occurrence of the hydrocoral Millepora (Hydrozoa: Milleporidae) in the subtropical eastern Atlantic (Canary Islands): is the colonization related to climatic events?

    Science.gov (United States)

    Clemente, S.; Rodríguez, A.; Brito, A.; Ramos, A.; Monterroso, Ó.; Hernández, J. C.

    2011-03-01

    The occurrence of a hydrocoral of the genus Millepora has been recorded for the first time in the eastern subtropical Atlantic (Tenerife, Canary Islands), at a latitude of 11º N of its previously known northernmost limit of distribution in the Cape Verde Islands. The moderate development of the colonies, their fast growth rate and very restricted location indicate a recent colonization process, possibly related to an extreme climatic event that took place in the summer of 2004, adding to the rising seawater temperatures in the region during recent years.

  10. The 2011 volcanic crisis at El Hierro (Canary Islands): monitoring ground deformation through tiltmeter and gravimetric observations

    Science.gov (United States)

    Arnoso, J.; Montesinos, F. G.; Benavent, M.; Vélez, E. J.

    2012-04-01

    El Hierro is an ocean island located at the western end of the Canary Islands, and along with Tenerife and La Palma islands have been the most geologically active in the recent past. The island has a triple armed rift and, presently, is at the stage of growth, representing the summit of a volcanic shield elevating from the seafloor at depth of 4000 m up to 1501 m above the sea level (Münn et al., 2006; Carracedo et al., 1999). Since July 19th, 2011 seismic activity has produced more than 11950 events up to date. The seismic crisis resulted in a volcanic eruption that began on October 10th, being still currently active. The new volcano is located 2 km off the coast and about 300 m depth, in the submarine flank of the southern rift of the island, which is extended some 40 km length. Since September 2004 until November 2010 two continuous tilt stations were installed at the north, Balneario site (BA), and at the center of the island, Aula de la Naturaleza (AU) site. Both stations were used to assess the pattern of local ground movements in the island. When seismic swarm started on past July 2011, we have reinstalled both tilt stations (BA and AU) and 2 new ones located at the south of the island, namely Montaña Quemada (MQ) and Restinga (RE) sites. We have used short base platform tiltmeters that measure ground tilts with resolutions varying from 0.1 up to 0.01 microradians (µrad). On October 8th, a 4.4 magnitude earthquake took place and is supposed that fractured the ocean crust at some 8-10 km off the south coast of the island and about 1000 m depth. Typical spike signals were observed at the tilt stations. Two days after, the eruption onset was recorded also at tilt stations through a remarkable increase of the high frequency signal, being of large amplitude the components (radial) orientated towards the new volcano edifice. When compared with previous tiltmeter records in the island, tilt pattern were clearly modified several times at the stations when strong

  11. Hydrothermal alteration of a seamount complex on La Palma, Canary Islands: Implications for metamorphism in accreted terranes

    Science.gov (United States)

    Schiffman, P.; Staudigel, H.

    1994-02-01

    The hydrothermal metamorphism of a sequence of Pliocene-age seamount extrusive and volcaniclastic rocks on La Palma, Canary Islands, is characterized by a relatively complete low-pressure-high-temperature facies series encompassing the zeolite, prehnite-pumpellyite, and greenschist facies. The observed mineral zonations imply metamorphic gradients of 200-300 °C/km. The metamorphism of the seamount, at least in its core region, is distinct from ocean-floor metamorphism: the former is characterized by a serially continuous facies series encompassing zeolite, prehnite-pumpellyite, and greenschist assemblages, and the latter by a discontinuous metamorphic gradient in which prehnite-pumpellyite assemblages are absent. These metamorphic features, presumably reflecting fundamental thermal-tectonic differences between extending oceanic crust at mid- oceanic ridges vs. the more static crust underlying seamount volcanoes, should aid in the recognition of incoherent fragments of seamount metamorphic rocks within accreted terranes which typically have undergone subsequent higher pressure-temperature regional metamorphism, albeit to comparable grades.

  12. First-order estimate of the Canary Islands plate-scale stress field: Implications for volcanic hazard assessment

    Science.gov (United States)

    Geyer, A.; Martí, J.; Villaseñor, A.

    2016-06-01

    In volcanic areas, the existing stress field is a key parameter controlling magma generation, location and geometry of the magmatic plumbing systems and the distribution of the resulting volcanism at surface. Therefore, knowing the stress configuration in the lithosphere at any scale (i.e. local, regional and plate-scale) is fundamental to understand the distribution of volcanism and, subsequently, to interpret volcanic unrest and potential tectonic controls of future eruptions. The objective of the present work is to provide a first-order estimate of the plate-scale tectonic stresses acting on the Canary Islands, one of the largest active intraplate volcanic regions of the World. In order to obtain the orientation of the minimum and maximum horizontal compressive stresses, we perform a series of 2D finite element models of plate scale kinematics assuming plane stress approximation. Results obtained are used to develop a regional model, which takes into account recognized archipelago-scale structural discontinuities. Maximum horizontal compressive stress directions obtained are compared with available stress, geological and geodynamic data. The methodology used may be easily applied to other active volcanic regions, where a first order approach of their plate/regional stresses can be essential information to be used as input data for volcanic hazard assessment models.

  13. Photophysiological variability and its influence on primary production in the NW Africa-Canary Islands coastal transition zone

    Science.gov (United States)

    Figueiras, F. G.; Arbones, B.; Montero, M. F.; Barton, E. D.; Arístegui, J.

    2016-05-01

    Photophysiological variability and its influence on primary production were studied in the NW Africa-Canary Islands coastal transition zone. The region showed strong mesoscale activity, in which upwelling filaments and island eddies interacted to cause significant vertical displacements of the deep chlorophyll maximum (DCM). Oligotrophic stations both in the open ocean and within anticyclonic eddies were characterised by low values of integrated chlorophyll (33 ± 4 mg chl a m- 2) and dominance of pico- and nanophytoplankton, while stations associated with filaments and cyclonic eddies showed moderate chl a values (50 ± 17 mg m- 2). Shelf stations affected by upwelling exhibited the highest chl a (112 ± 36 mg m- 2) with microphytoplankton dominance. Photosynthetic variables in the three groups of stations showed similar depth gradients, with maximum photosynthetic rates (PmB) decreasing with depth and maximum quantum yields (ϕm) increasing with depth. However, the increase with depth of ϕm was not so evident in shelf waters where nutrients were not depleted at the surface. Primary production (PP) displayed a coast-ocean gradient similar to that of chl a, with highest values (2.5 ± 1.2 g C m- 2 d- 1) at the eutrophic shelf stations and lowest (0.36 ± 0.11 g C m- 2 d- 1) at the oligotrophic stations. Nevertheless, integrated PP at the oligotrophic stations was not related to integrated chl a concentration but was positively (r = 0.95) correlated to carbon fixation at the DCM and negatively (r = - 0.85) correlated to the depth of the DCM, suggesting that light, and not phytoplankton biomass, was the main factor controlling PP in oligotrophic environments. It is concluded that downward displacements of the DCM, either by convergence fronts or downwelling at the core of anticyclones can significantly reduce PP in the oligotrophic ocean.

  14. Fusion of WorldView-2 and LiDAR Data to Map Fuel Types in the Canary Islands

    Directory of Open Access Journals (Sweden)

    Alfonso Alonso-Benito

    2016-08-01

    Full Text Available Wildland fires are one of the factors causing the deepest disturbances on the natural environment and severely threatening many ecosystems, as well as economic welfare and public health. Having accurate and up-to-date fuel type maps is essential to properly manage wildland fire risk areas. This research aims to assess the viability of combining Geographic Object-Based Image Analysis (GEOBIA and the fusion of a WorldView-2 (WV2 image and low density Light Detection and Ranging (LiDAR data in order to produce fuel type maps within an area of complex orography and vegetation distribution located in the island of Tenerife (Spain. Independent GEOBIAs were applied to four datasets to create four fuel type maps according to the Prometheus classification. The following fusion methods were compared: Image Stack (IS, Principal Component Analysis (PCA and Minimum Noise Fraction (MNF, as well as the WV2 image alone. Accuracy assessment of the maps was conducted by comparison against the fuel types assessed in the field. Besides global agreement, disagreement measures due to allocation and quantity were estimated, both globally and by fuel type. This made it possible to better understand the nature of disagreements linked to each map. The global agreement of the obtained maps varied from 76.23% to 85.43%. Maps obtained through data fusion reached a significantly higher global agreement than the map derived from the WV2 image alone. By integrating LiDAR information with the GEOBIAs, global agreement improvements by over 10% were attained in all cases. No significant differences in global agreement were found among the three classifications performed on WV2 and LiDAR fusion data (IS, PCA, MNF. These study’s findings show the validity of the combined use of GEOBIA, high-spatial resolution multispectral data and low density LiDAR data in order to generate fuel type maps in the Canary Islands.

  15. Pediatrics patients dose for nuclear medicine studies in Canary Island; Dosis a pacientes pediatricos por estudios de medicina nuclear en Canarias

    Energy Technology Data Exchange (ETDEWEB)

    Hernande-Armas, J.; Catalan Acosta, A.; Gonzalez Diaz, A.; Afonso Segado, M.; Gomez, M. A.; Hernandez Briz, M. J.

    2006-07-01

    A large amount of information about Nuclear Medicine procedures on paediatric patients in Canary Islands has been compiled here. The aim of this work has been to find out the radiation exposure of these patients to evaluate the radiological impact which is caused by this type of medical practice. Thus, the effective dose to the patients of the big Hospitals of the Canaries was calculated. The information corresponding to 1920 procedures made to patients less than 15 years old during 2001 and 2006 was used for this purpose. The most frequent procedure was renal studies (56%) follow by pulmonary (17%) and bone studies (7.6%). The range of effective dose was 0.06 mSv to 44 mSv. The effective collective dose was 7.11 man-Sv. The main contributors to the collective dose were the procedures made with gallium citrate followed by renal studies. (Author)

  16. Soil degradation under reclaimed wastewater in arenados (Lanzarote, Canary Islands, Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Tejedor, M.; Jimenez, C.; Hernandez-Moreno, J. M.; Diaz, F.

    2009-07-01

    In the Island of Lanzarote, one of the most arid zones of the EU, a traditional farming system based on the soil mulching with basaltic tephra, locally known as arenados, was developed since the 18th century. This dry-framing system accounts currently for more than 21% of the island surface. However, in the last decades, this system has been transformed with the incorporation of irrigation, due to the availability of new non-conventional water resources (desalinised and reclaimed municipal wastewater). (Author)

  17. On the detection of thermohygrometric differences of Juniperus turbinata habitat between north and south faces in the island of El Hierro (Canary Islands)

    Science.gov (United States)

    Salva-Catarineu, Montserrat; Salvador-Franch, Ferran; Lopez-Bustins, Joan A.; Padrón-Padrón, Pedro A.; Cortés-Lucas, Amparo

    2016-04-01

    The current extent of Juniperus turbinata in the island of El Hierro is very small due to heavy exploitation for centuries. The recovery of its natural habitat has such a high environmental and scenic interest since this is a protected species in Europe. The study of the environmental factors that help or limit its recovery is indispensable. Our research project (JUNITUR) studied the populations of juniper woodlands in El Hierro from different environments. These environments are mainly determined by their altitude and exposure to north-easterly trade winds. The main objective of this study was to compare the thermohygrometric conditions of three juniper woodlands: La Dehesa (north-west face at 528 m a.s.l.), El Julan (south face at 996 m a.s.l.) and Sabinosa (north face at 258 m a.s.l.). They are located at different altitude and orientation in El Hierro and present different recovery rates. We used air sensor data loggers fixed to tree branches for recording hourly temperature and humidity data in the three study areas. We analysed daily data of three annual cycles (from September 2012 to August 2015). Similar thermohygrometric annual cycles among the three study areas were observed. We detected the largest differences in winter temperature and summer humidity between the north (to windward) (Sabinosa and La Dehesa) and south (to leeward) (El Julan) faces of the island. The juniper woodland with a highest recovery rate (El Julan) showed the most extreme temperature conditions in both winter and summer seasons. The results of this project might contribute to the knowledge of the juniper bioclimatology in El Hierro, where there is the biggest population of Juniperus turbinata throughout the Canary Islands.

  18. Enhancement of sub-daily positioning solutions for surface deformation surveillance at El Hierro volcano (Canary Islands, Spain)

    Science.gov (United States)

    Prates, G.; García, A.; Fernández-Ros, A.; Marrero, J. M.; Ortiz, R.; Berrocoso, M.

    2013-06-01

    El Hierro Island in the Canary Archipelago recently experienced a submerged eruption a few kilometers off its southern shore, detected 2011 October 10 on the island's south-rift alignment. The seismic activity suddenly increased around mid 2011 July, and ground deformation was then detected on the only geodetic benchmark that is continuously observed by global navigation satellite systems techniques and provides public data access. Based on that information, several other global navigation satellite system signal receivers were deployed on the island to provide continuous observation. For data collected by these receivers, a processing strategy was applied to achieve millimeter-level half-hourly positioning solutions. Position updates every 24 h are satisfactory to determine tectonic-plates' velocities. Updates near 1 s or less are required to characterize seismic waves. In between, minute-level updates are well suited for monitoring active volcano's inflation or deflation, providing an optimal time resolution of the local ground deformation. In half-hourly positioning solutions, the heterogeneous satellites' distribution in their orbital planes gives different constraints during satellite-constellation revolution, which can bias the solutions. Also, several geophysical influences can bias the solutions, including those related to gravitational movements. These influences have mostly semi-diurnal periodicities and may be considered Gaussian colored noise on the position's time series. Daily solutions that average out these influences can be applied in active volcanoes, but they can impose some limitations because they average the daily deformation, and the update waiting time is not suitable when near real-time surveillance is mandatory. These semi-diurnal biases do need to be removed or minimized to achieve millimeter-level sub-daily positioning solutions, however, and to do so, a discrete Kalman filter was applied to enhance the half-hourly positioning solutions

  19. Causes of Raptor Admissions to a Wildlife Rehabilitation Center in Tenerife (Canary Islands)full access

    OpenAIRE

    2010-01-01

    We studied the causes of raptor admissions to the only wildlife rehabilitation center on the largest island of the Canarian Archipelago (Tenerife) over ten years (1998–2007). A total of 2611 birds of prey, belonging to nine falconiform diurnal raptor and four strigiform species, were admitted. The Eurasian Kestrel (Falco tinnunculus) and the Long-eared Owl (Asio otus) were the species most commonly admitted and jointly made up 85.6% of admissions. The most frequent causes of admission to the ...

  20. Diffuse degassing He/CO2 ratio before and during the 2011-12 El Hierro submarine eruption, Canary Islands

    Science.gov (United States)

    Padrón, Eleazar; Hernández, Pedro A.; Melián, Gladys V.; Barrancos, José; Padilla, Germán; Pérez, Nemesio M.; Dionis, Samara; Rodríguez, Fátima; Asensio-Ramos, María; Calvo, David

    2015-04-01

    El Hierro Island (278 km2) is the youngest and the SW-most of the Canary Islands. On July 16, 2011, a seismic-volcanic crisis started with the occurrence of more than 11,900 seismic events and significant deformation along the island, culminating with the eruption onset in October 12. Since at El Hierro Islands there are not any surface geothermal manifestation (fumaroles, etc), we have focused our studies on soil degassing surveys. Between July 2011 to March 2012, seventeen diffuse CO2 and He emissions soil gas surveys were undertaken at El Hierro volcanic system (600 observation sites) with the aim to investigate the relationship between their temporal variations and the volcanic activity (Padrón et al., 2013; Melián et al., 2014). Based on the diffuse He/CO2 emission ratio, a sharp increase before the eruption onset was observed, reaching the maximum value on September 26 (6.8×10-5), sixteen days before the occurrence of the eruption. This increase coincided with an increase in seismic energy release during the volcanic unrest and occurred together with an increase on the 3He/4He isotopic ratio in groundwaters from a well in El Hierro Island (Padrón et al., 2013; from 2-3 RA to 7.2 RA where RA = 3He/4He ratio in air), one month prior to the eruption onset. Early degassing of new gas-rich magma batch at depth could explain the observed increase on the He/CO2 ratio, causing a preferential partitioning of CO2 in the gas phase with respect to the He, due to the lower solubility of CO2 than that of He in basaltic magmas. During the eruptive period (October 2011-March 2012) the prevalence of a magmatic CO2-dominated component is evident, as indicated by the generally lower He/CO2 ratios and high 3He/4He values (Padrón et al., 2013). The onset of the submarine eruption might have produced a sudden release of volcanic gases, and consequently, a decrease in the volcanic gas pressure of the magma bodies moving beneath the island, reflected by a drastic decrease in

  1. Migrant biomass and respiratory carbon flux by zooplankton and micronekton in the subtropical northeast Atlantic Ocean (Canary Islands)

    Science.gov (United States)

    Ariza, A.; Garijo, J. C.; Landeira, J. M.; Bordes, F.; Hernández-León, S.

    2015-05-01

    Diel Vertical Migration (DVM) in marine ecosystems is performed by zooplankton and micronekton, promoting a poorly accounted export of carbon to the deep ocean. Major efforts have been made to estimate carbon export due to gravitational flux and to a lesser extent, to migrant zooplankton. However, migratory flux by micronekton has been largely neglected in this context, due to its time-consuming and difficult sampling. In this paper, we evaluated gravitational and migratory flux due to the respiration of zooplankton and micronekton in the northeast subtropical Atlantic Ocean (Canary Islands). Migratory flux was addressed by calculating the biomass of migrating components and measuring the electron transfer system (ETS) activity in zooplankton and dominant species representing micronekton (Euphausia gibboides, Sergia splendens and Lobianchia dofleini). Our results showed similar biomass in both components. The main taxa contributing to DVM within zooplankton were juvenile euphausiids, whereas micronekton were mainly dominated by fish, followed by adult euphausiids and decapods. The contribution to respiratory flux of zooplankton (3.4 ± 1.9 mg C m-2 d-1) was similar to that of micronekton (2.9 ± 1.0 mg C m-2 d-1). In summary, respiratory flux accounted for 53% (range 23-71) of the gravitational flux measured at 150 m depth (11.9 ± 5.8 mg C m-2 d-1). However, based on larger migratory ranges and gut clearance rates, micronekton are expected to be the dominant component that contributes to carbon export in deeper waters. Micronekton estimates in this paper as well as those in existing literature, although variable due to regional differences and difficulties in calculating their biomass, suggest that carbon fluxes driven by this community are important for future models of the biological carbon pump.

  2. Retrieval and validation of carbon dioxide, methane and water vapor for the Canary Islands IR-laser occultation experiment

    Directory of Open Access Journals (Sweden)

    V. Proschek

    2014-11-01

    Full Text Available The first ground-based experiment to prove the concept of a novel space-based observation technique for microwave and infrared-laser occultation between Low Earth Orbit satellites (LMIO was performed in the Canary Islands between La Palma and Tenerife in July 2011. This experiment aimed to demonstrate the infrared-laser differential transmission principle for the measurement of greenhouse gases (GHGs in the free atmosphere. Such global and long-term stable measurements of GHGs, accompanied also by measurements of thermodynamic parameters and line-of-sight wind in a self-calibrating way, have become very important for climate change monitoring. The experiment delivered promising initial data for demonstrating the new observation concept by retrieving volume mixing ratios of GHGs along a ~ 144 km signal path at altitudes of ~ 2.4 km. Here, we present a detailed analysis of the measurements, following a recent publication that introduced the experiment's technical setup and first results for an example retrieval of CO2. We present the observational and validation datasets, the latter simultaneously measured at the transmitter and receiver sites, the measurement data handling, and the differential transmission retrieval procedure. We also determine the individual and combined uncertainties influencing the results and present the retrieval results for 12CO2, 13CO2, C18OO, H2O and CH4. The new method is found to have a reliable basis for monitoring of greenhouse gases such as CO2, CH4, and H2O in the free atmosphere.

  3. After Timanfaya: overpopulation and soil erosion in the north of Lanzarote (Canary Islands); Tras Timanfaya: susperpoblacion y erosion de suelo en el norte de Lanzarote

    Energy Technology Data Exchange (ETDEWEB)

    Criado, C.; Romero, C.; Solar, V.

    2009-07-01

    The eruption of Timanfaya (1730-1736) has been the most important volcanic activity on Canary Islands during historical times (after XV Century). The lave flows and piroclastic layers buried at least 1/4 of Lanzarote surface. Overall the island we can see artificial cross-sections showing ash layers, overlapping paleargids soils or interbedded between alluvial sediment on the bottom of in filled valleys. Sedimentological analysis has been applied on four cross-section located along the island. These data, together with historical information and pottery remains, allow conclude a very recent age for many of this layers, produced by a strong erosion input started by the overgrazing produced by the concentration of livestock during the volcanic crisis. (Author) 6 refs.

  4. Abundance and Distribution of Sperm Whales in the Canary Islands: Can Sperm Whales in the Archipelago Sustain the Current Level of Ship-Strike Mortalities?

    Directory of Open Access Journals (Sweden)

    Andrea Fais

    Full Text Available Sperm whales are present in the Canary Islands year-round, suggesting that the archipelago is an important area for this species in the North Atlantic. However, the area experiences one of the highest reported rates of sperm whale ship-strike in the world. Here we investigate if the number of sperm whales found in the archipelago can sustain the current rate of ship-strike mortality. The results of this study may also have implications for offshore areas where concentrations of sperm whales may coincide with high densities of ship traffic, but where ship-strikes may be undocumented. The absolute abundance of sperm whales in an area of 52933 km2, covering the territorial waters of the Canary Islands, was estimated from 2668 km of acoustic line-transect survey using Distance sampling analysis. Data on sperm whale diving and acoustic behaviour, obtained from bio-logging, were used to calculate g(0 = 0.92, this is less than one because of occasional extended periods when whales do not echolocate. This resulted in an absolute abundance estimate of 224 sperm whales (95% log-normal CI 120-418 within the survey area. The recruitment capability of this number of whales, some 2.5 whales per year, is likely to be exceeded by the current ship-strike mortality rate. Furthermore, we found areas of higher whale density within the archipelago, many coincident with those previously described, suggesting that these are important habitats for females and immature animals inhabiting the archipelago. Some of these areas are crossed by active shipping lanes increasing the risk of ship-strikes. Given the philopatry in female sperm whales, replacement of impacted whales might be limited. Therefore, the application of mitigation measures to reduce the ship-strike mortality rate seems essential for the conservation of sperm whales in the Canary Islands.

  5. Abundance and Distribution of Sperm Whales in the Canary Islands: Can Sperm Whales in the Archipelago Sustain the Current Level of Ship-Strike Mortalities?

    Science.gov (United States)

    Fais, Andrea; Lewis, Tim P; Zitterbart, Daniel P; Álvarez, Omar; Tejedor, Ana; Aguilar Soto, Natacha

    2016-01-01

    Sperm whales are present in the Canary Islands year-round, suggesting that the archipelago is an important area for this species in the North Atlantic. However, the area experiences one of the highest reported rates of sperm whale ship-strike in the world. Here we investigate if the number of sperm whales found in the archipelago can sustain the current rate of ship-strike mortality. The results of this study may also have implications for offshore areas where concentrations of sperm whales may coincide with high densities of ship traffic, but where ship-strikes may be undocumented. The absolute abundance of sperm whales in an area of 52933 km2, covering the territorial waters of the Canary Islands, was estimated from 2668 km of acoustic line-transect survey using Distance sampling analysis. Data on sperm whale diving and acoustic behaviour, obtained from bio-logging, were used to calculate g(0) = 0.92, this is less than one because of occasional extended periods when whales do not echolocate. This resulted in an absolute abundance estimate of 224 sperm whales (95% log-normal CI 120-418) within the survey area. The recruitment capability of this number of whales, some 2.5 whales per year, is likely to be exceeded by the current ship-strike mortality rate. Furthermore, we found areas of higher whale density within the archipelago, many coincident with those previously described, suggesting that these are important habitats for females and immature animals inhabiting the archipelago. Some of these areas are crossed by active shipping lanes increasing the risk of ship-strikes. Given the philopatry in female sperm whales, replacement of impacted whales might be limited. Therefore, the application of mitigation measures to reduce the ship-strike mortality rate seems essential for the conservation of sperm whales in the Canary Islands.

  6. Genus Gambierdiscus in the Canary Islands (NE Atlantic Ocean) with description of Gambierdiscus silvae sp. nov., a new potentially toxic epiphytic benthic dinoflagellate.

    Science.gov (United States)

    Fraga, Santiago; Rodríguez, Francisco

    2014-12-01

    Species of the dinoflagellate genus Gambierdiscus are the cause of Ciguatera Fish Poisoning, common in tropical areas. Nevertheless, until recently this syndrome was not reported in the NE Atlantic Ocean. A new photosynthetic dinoflagellate species, Gambierdiscus silvae sp. nov. is described based on samples taken from tide pools on rocky shores of the Canary Islands (NE Atlantic Ocean). Its morphology was studied by light and scanning electron microscopy. The new species is anterioposteriorly compressed, lenticular in shape with an epitheca slightly higher than the hypotheca. It is round in apical view and has a thick smooth theca with many scattered pores. Plate formula is Po, 4', 0a, 6″, 6c, 6s?, 5'″, 0p, 2″″. Plate 2' is hatchet-shaped and Plate 2″″ is very wide and the largest of the hypotheca. Phylogenies inferred from the large subunit nuclear rRNA showed that three G. silvae strains clustered in a well supported sister clade to G. polynesiensis, distinct from the other species. G. australes was observed for the first time in the Atlantic, together with G. excentricus already reported from these islands. This work increases the number of Gambierdiscus species described and shows their unexpected diversity in the Canary Islands.

  7. Multi-level magmatic system of El Hierro Island (Canary Islands) constrained by multi-satellite radar interferometry measurements during the 2011-2012 eruption

    Science.gov (United States)

    Gonzalez, P. J.; Samsonov, S. V.; Pepe, S.; Tiampo, K. F.; Tizzani, P.; Fernandez, J.; Sansosti, E.

    2012-12-01

    Starting from July 2011, anomalous seismicity was observed at El Hierro Island (Canary Islands, Spain). During the following three months, seismic activity increased both in number of events and in magnitude, while expanding over a large area. In early October 2011 the process led to a submarine eruption, with some uncertainty about the location and timing of vent(s) opening. The site of the eruption was ~10 km from the initial and main earthquake loci, indicative of significant lateral migration. Here, we conduct a multi-frequency, multi-sensor interferometric analysis of space-borne radar images acquired using three different satellites (Radarsat-2, ASAR-ENVISAT and COSMO-SkyMed). Radar interferometry is used to measure the deformation that occurred from December 2009 to July 2012. InSAR data fully captures both the pre-, co- and post-eruptive phases. Subsequently, elastic modeling of the ground deformation is employed to constrain the dynamics associated with the magmatic and eruptive activity. This study represents one of the first geodetically-constrained active magmatic plumbing system model for any of the Canary Islands volcanoes, and one of the few examples of geodetic measurement of submarine volcanic activity to date. It reveals a complex magmatic system with multiple levels of stagnation, a deeper central system (~8.5 km depth) and a shallower magma reservoir at the flank of the southern rift (~4 km depth). Before eruption, magma propagated ~5 km downrift towards the eruption fissure. From mid-November 2011 to early January 2012 the system was continuously recharged from source(s) deeper than 10 km, which contributed to a relatively atypical long duration for a basaltic eruption (~5 months). The submarine eruption finished on early March 2012. However, on June 24, 2012 the seismic activity resumed and intense ground deformation has been recorded. The anomalous seismicity continued for a month depicting a clear, but different migration path with respect

  8. Epidemiological survey of canine heartworm disease on the island of Gran Canaria (Canary Islands - Spain) between 2000 and 2008.

    Science.gov (United States)

    Montoya-Alonso, J A; Carretón, E; Juste, M C; Mellado, I; Morchón, R; Simón, F

    2010-10-11

    Canine cardiopulmonary dirofilariosis caused by Dirofilaria immitis is endemic on the island of Gran Canaria. Epidemiological surveys have shown differences in the prevalence of heartworm disease in the canine population of the island between 1989 and 1998. The aim of the present study was to follow-up the prevalence of D. immitis in both the canine population as a whole and the Canarian Warren Hound population on Gran Canaria between 2000 and 2008. Prevalences observed were always significantly higher in the Canarian Warren Hound population than in the entire canine population. A significant decrease in the prevalence (from 30.19% to 19.36%) in the whole population was observed. In the Canarian Warren Hound the prevalence decreased slightly between 2000 and 2007 (40.42-34.65%), rising in 2008 to values higher than those observed at the beginning of follow-up study (41.6%). These changes are mainly attributed to lack of preventive chemotherapy and the prolonged exposure of the Canarian Warren Hound to mosquito bites. As this breed can act as a natural reservoir in Gran Canaria, regular surveillance is needed to detect changes in the epidemiological picture on this island.

  9. Monitoring the NW volcanic rift-zone of Tenerife, Canary Islands, Spain: sixteen years of diffuse CO_{2} degassing surveys

    Science.gov (United States)

    Rodríguez, Fátima; Halliwell, Simon; Butters, Damaris; Padilla, Germán; Padrón, Eleazar; Hernández, Pedro A.; Pérez, Nemesio M.

    2016-04-01

    Tenerife is the largest of the Canary Islands and, together with Gran Canaria, is the only one that has developed a central volcanic complex characterized by the eruption of differentiated magmas. At present, one of the most active volcanic structures in Tenerife is the North-West Rift-Zone (NWRZ), which has hosted two historical eruptions: Arenas Negras in 1706 and Chinyero in 1909. Since the year 2000, 47 soil CO2 efflux surveys have been undertaken at the NWRZ of Tenerife Island to evaluate the temporal and spatial variations of CO2 efflux and their relationships with the volcanic-seismic activity. We report herein the last results of diffuse CO2 efflux survey at the NWRZ carried out in July 2015 to constrain the total CO2 output from the studied area. Measurements were performed in accordance with the accumulation chamber method. Spatial distribution maps were constructed following the sequential Gaussian simulation (sGs) procedure. During 2015 survey, soil CO2 efflux values ranged from non-detectable up to 103 g m-2 d-1. The total diffuse CO2 output released to atmosphere was estimated at 403 ± 17 t d-1, values higher than the background CO2 emission estimated on 143 t d-1. For all campaigns, soil CO2 efflux values ranged from non-detectable up to 141 g m-2 d-1, with the highest values measured in May 2005. Total CO2 output from the studied area ranged between 52 and 867 t d-1. Temporal variations in the total CO2 output showed a temporal correlation with the onsets of seismic activity, supporting unrest of the volcanic system, as is also suggested by anomalous seismic activity recorded in the area during April 22-29, 2004. Spatial distribution of soil CO2 efflux values also showed changes in magnitude and amplitude, with higher CO2 efflux values located along a trending WNW-ESE area. Subsurface magma movement is proposed as a cause for the observed changes in the total output of diffuse CO2 emission, as well as for the spatial distribution of soil CO2 efflux

  10. Deployment of a seismic array for volcano monitoring during the ongoing submarine eruption at El Hierro, Canary Islands

    Science.gov (United States)

    Abella, R.; Almendros, J.; Carmona, E.; Martin, R.

    2012-04-01

    On 17 July 2011 there was an important increase of the seismic activity at El Hierro (Canary Islands, Spain). This increase was detected by the Volcano Monitoring Network (Spanish national seismic network) run by the Instituto Geográfico Nacional (IGN). As a consequence, the IGN immediately deployed a dense, complete monitoring network that included seismometers, GPS stations, geochemical equipment, magnetometers, and gravity meters. During the first three months of activity, the seismic network recorded over ten thousand volcano-tectonic earthquakes, with a maximum magnitude of 4.6. On 10 October 2011 an intense volcanic tremor started. It was a monochromatic signal, with variable amplitude and frequency content centered at about 1-2 Hz. The tremor onset was correlated with the initial stages of the submarine eruption that occurred from a vent located south of El Hierro island, near the village of La Restinga. At that point the IGN, in collaboration with the Instituto Andaluz de Geofísica, deployed a seismic array intended for volcanic tremor monitoring and analysis. The seismic array is located about 7 km NW of the submarine vent. It has a 12-channel, 24-bit data acquisition system sampling each channel at 100 sps. The array is composed by 1 three-component and 9 vertical-component seismometers, distributed in a flat area with an aperture of 360 m. The data provided by the seismic array are going to be processed using two different approaches: (1) near-real-time, to produce information that can be useful in the management of the volcanic crisis; and (2) detailed investigations, to study the volcanic tremor characteristics and relate them to the eruption dynamics. At this stage we are mostly dedicated to produce fast, near-real-time estimates. Preliminary results have been obtained using the maximum average cross-correlation method. They indicate that the tremor wavefronts are highly coherent among array stations and propagate across the seismic array with an

  11. Lead and cadmium levels in coastal benthic algae (seaweeds) of Tenerife, Canary Islands.

    Science.gov (United States)

    Lozano, Gonzalo; Hardisson, Arturo; Gutiérrez, Angel José; Lafuente, María Anunciación

    2003-01-01

    Lead and cadmium levels of some species of brown-algae (Phaeophyta) from the mesolittoral (intertidal area) of the Island of Tenerife (central-eastern Atlantic) were determined by Atomic Absorption Spectrometry. The quality control was carried out using a standard "CRM 279 Ulva lactuca". The mean, minimum and maximum concentrations were 11.21, 2.090 and 81.795 microg/g/dw; and 1.13, 0.190 and 5.130 microg/g/dw for lead and cadmium, respectively. The fact that samples registering the highest cadmium concentrations were the same as those which showed the highest lead level corresponding to a sampling station nearby an urban water outlet could be relevant.

  12. Modern pollen rain in Canary Island ecosystems and its implications for the interpretation of fossil records

    DEFF Research Database (Denmark)

    de Nascimento, Lea; Nogué, Sandra; Fernández-Lugo, Silvia

    2015-01-01

    types are represented in the pollen rain. In this study we address this key knowledge gap within Canarian vegetation science, taking the island of Tenerife as a model. Based on quantitative and qualitative data we analysed pollen-vegetation relationships to test whether different vegetation types can...... be discriminated by means of their pollen rain composition, to identify under- and over-represented taxa, and to test the match between modern pollen rain and fossil pollen assemblages. We found clear differences in pollen composition and abundance among major Canarian vegetation types. We also identified good......-represented (.Pinus, Morella and Ericaceae trees, Chenopodiaceae, Poaceae, Rumex and Urticaceae herbs and shrubs) or under-represented (Lauraceae trees, Fabaceae and Euphorbia shrubs). Results indicate that pollen composition is a good reflection of vegetation in Canarian ecosystems and can be used effectively...

  13. Subtidal soft-bottom macroinvertebrate communities of the Canary Islands. An ecological approach

    Directory of Open Access Journals (Sweden)

    Oscar Monterroso

    2012-03-01

    Full Text Available The Canarian archipelago is characterized by a mosaic of soft-bottoms such as Cymodocea nodosa meadows, Caulerpa spp. meadows, mäerl bottoms, sabellid fields and bare sandy seabeds, including various macroinfaunal communities. Vegetated habitats (e.g. Cymodocea and Caulerpa maintain more diverse communities than the non-vegetated seabeds. The results indicated that Caulerpa meadows and, to a lesser extent, Cymodocea nodosa and sabellid fields are the richest and most diverse ecosystems in the study area. Moreover, biodiversity differences among islands could be detected with maximum values on the eastern islands (Lanzarote and Gran Canaria and lowest values on the western ones (La Palma.O arquipélago das Canárias é caracterizado por um mosaico de fundos inconsolidados contendo bancos de Cymodocea nodosa, Caulerpa spp., fundos calcários, bancos de sabelídeos e sedimento não biogênico, que abrigam diferentes comunidades da macrofauna. Ambientes vegetados (Cymodocea e Caulerpa possuem comunidades mais diversificadas quando comparados aos ambientes de fundos não vegetados. Os resultados do presente estudo indicaram que os bancos de Caulerpa, primeiramente, e em seguida os bancos de Cymodocea nodosa e de sabelídeos, formam os sistemas mais ricos e diversificados da área. Além disso, puderam também ser detectadas diferenças de biodiversidade entre as ilhas do arquipélago, sendo os valores mais altos localizados nas ilhas ao leste (Lanzarote e Gran Canaria e os menores nas ilhas à oeste (La Palma.

  14. Hazard assessment at Teide-Pico Viejo volcanic complex (Tenerife, Canary Islands)

    Science.gov (United States)

    Marti, Joan; Sobradelo, Rosa; Felpeto, Alicia

    2010-05-01

    Mid to long-term hazard assessment is conducted at Teide-Pico Viejo volcanic complex as a first step to evaluate volcanic risk in Tenerife, a densely populated island that is one of the biggest tourist destinations in Europe. Teide-Pico Viejo stratovolcanoes started to grow up in the interior of the Las Cañadas caldera, in the central part of Tenerife, about 190 ka ago, after the formation of the youngest sector of the caldera. Since then they have produced more than 150 km3 of rocks which represent a complete basanite to phonolite series. Eruptive activity at Teide-Pico Viejo complex has been traditionally considered as mostly effusive, but new field data has revealed that explosive activity of phonolitic and basaltic magmas, including plinian and subplinian eruptions and the generation of a wide range of PDCs, has also been significant, particularly during the last 30 ka. Most of the Teide products have been emplaced towards the north, inside the Icod and La Orotava valleys, or at the interior of the caldera, while towards the south the caldera wall has stopped the emplacement of such products from going further. The last eruption from the Teide-Pico Viejo central vents, the Lavas Negras eruption, took place about 1000 years ago, but younger eruptive episodes have occurred along the flanks of these stratovolcanoes. Despite the occurrence of numerous eruptions during the last 30 ka and the existence of unequivocal signs of activity in historical times (fumaroles, seismicity) and, even, a clear unrest episode that started in 2004 and is still ongoing, Teide-Pico Viejo stratovolcanoes have not been considered as a major threat by some scientists and also by the local authorities who have dedicated minimum attention to them in the recently approved regional emergency plan. If this view prevails it is obvious that risk mitigation in Tenerife will not succeed. In order to contribute to change that view on the danger potential of Teide-Pico Viejo, and to insist on the

  15. Respiratory allergies and skin test reactivity in high school students in Tenerife, Canary Islands, Spain.

    Science.gov (United States)

    García-Ramos Alonso, E; Fernández-Caldas, E; Seleznick, M J; Lockey, R F

    1992-01-01

    The prevalence of skin test reactivity to 22 aeroallergens and of allergic respiratory diseases was determined in 501 high school students on the island of Tenerife, Spain. Two hundred seventy-seven students (55.2%) had at least one positive prick skin test (wheal > or = 2 mm). Two hundred sixteen students (43.1%) had symptoms of upper or lower respiratory tract allergies [24 (4.7%) had asthma with or without rhinitis and 192 (38.3%) seasonal or perennial rhinitis alone]. Two hundred eighty-five students (56.8%) were asymptomatic. One hundred per cent of the students with asthma, 87.5% of the students with rhinitis and 27.7% of the asymptomatic students had at least one positive skin test. The prevalence of positive skin tests was significantly higher in symptomatic than in asymptomatic students (p = 0.0001). One hundred seventy students (33.9%) had a family history of respiratory allergic diseases. The prevalence of positive skin tests among these students was significantly higher than in students without such history (p = 0.0001). Thus, there is a high prevalence of allergic respiratory diseases and skin test reactivity to aeroallergens among high school students in Tenerife. Significant correlations were found between family history, positive skin tests and respiratory allergic symptoms.

  16. Inbreeding depression under drought stress in the rare endemic Echium wildpretii (Boraginaceae) on Tenerife, Canary islands.

    Science.gov (United States)

    Sedlacek, Janosch; Schmid, Bernhard; Matthies, Diethart; Albrecht, Matthias

    2012-01-01

    How climate-change induced environmental stress may alter the effects of inbreeding in patchy populations of rare species is poorly understood. We investigated the fitness of progeny from experimental self- and cross-pollinations in eight populations of different size of Echium wildpretii, a rare endemic plant of the arid subalpine zone of the Canarian island of Tenerife. As control treatments we used open pollination and autonomous selfing. The seed set of open-pollinated flowers was 55% higher than that of autonomously selfed flowers, showing the importance of animal pollination for reproductive success. The seed set, seed mass and germination rate of seedlings of hand-selfed flowers was similar to that of hand-crossed flowers, indicating weak inbreeding depression (seed set -4.4%, seed mass -4.1%, germination -7.3%). Similarly, under normal watering there were no significant effects of inbreeding on seedling survival (-3.0%). However, under low watering of seedlings inbreeding depression was high (survival -50.2%). Seed set of open- and hand-outcrossed-pollinated flowers was higher in large than in small populations, possibly due to more frequent biparental inbreeding in the latter. However, later measures of progeny fitness were not significantly influenced by population size. We predict that increasing drought duration and frequency due to climate change and reductions of population sizes may increase inbreeding depression in this charismatic plant species and thus threaten its future survival in the longer term.

  17. Neoparamoeba branchiphila infections in moribund sea urchins Diadema aff. antillarum in Tenerife, Canary Islands, Spain.

    Science.gov (United States)

    Dyková, Iva; Lorenzo-Morales, Jacob; Kostka, Martin; Valladares, Basilio; Pecková, Hana

    2011-07-12

    A total of 109 sea urchins from 3 species collected in 2 localities off the coast of Tenerife Island, Spain, were examined for the presence of free-living amoebae in their coelomic fluid. Amoeba trophozoites were isolated exclusively from moribund individuals of long-spined sea urchins Diadema aff. antillarum (Philippi) (Echinoidea, Echinodermata) that manifested lesions related to sea urchin bald disease on their tests (16 out of 56 examined). No amoebae were detected in Arbacia lixula (L.) and Paracentrotus lividus (Lamarck). From the former sea urchin species, 8 strains, established from 10 primary isolates, were identified as Neoparamoeba branchiphila Dyková et al., 2005 using morphological and molecular methods. Results of this study (limited to the screening for free-living amoebae) together with data on agents of sea urchin mortalities reported to date justify the hypothesis that free-living amoebae play an opportunistic role in D. aff. antillarum mortality. The enlargement of the dataset of SSU rDNA sequences brought new insight into the phylogeny of Neoparamoeba species.

  18. Inbreeding depression under drought stress in the rare endemic Echium wildpretii (Boraginaceae on Tenerife, Canary islands.

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    Janosch Sedlacek

    Full Text Available How climate-change induced environmental stress may alter the effects of inbreeding in patchy populations of rare species is poorly understood. We investigated the fitness of progeny from experimental self- and cross-pollinations in eight populations of different size of Echium wildpretii, a rare endemic plant of the arid subalpine zone of the Canarian island of Tenerife. As control treatments we used open pollination and autonomous selfing. The seed set of open-pollinated flowers was 55% higher than that of autonomously selfed flowers, showing the importance of animal pollination for reproductive success. The seed set, seed mass and germination rate of seedlings of hand-selfed flowers was similar to that of hand-crossed flowers, indicating weak inbreeding depression (seed set -4.4%, seed mass -4.1%, germination -7.3%. Similarly, under normal watering there were no significant effects of inbreeding on seedling survival (-3.0%. However, under low watering of seedlings inbreeding depression was high (survival -50.2%. Seed set of open- and hand-outcrossed-pollinated flowers was higher in large than in small populations, possibly due to more frequent biparental inbreeding in the latter. However, later measures of progeny fitness were not significantly influenced by population size. We predict that increasing drought duration and frequency due to climate change and reductions of population sizes may increase inbreeding depression in this charismatic plant species and thus threaten its future survival in the longer term.

  19. Volcanic signatures in time gravity variations during the volcanic unrest on El Hierro (Canary Islands)

    Science.gov (United States)

    Sainz-Maza Aparicio, S.; Arnoso Sampedro, J.; Gonzalez Montesinos, F.; Martí Molist, J.

    2014-06-01

    Gravity changes occurring during the initial stage of the 2011-2012 El Hierro submarine eruption are interpreted in terms of the preeruptive signatures during the episode of unrest. Continuous gravity measurements were made at two sites on the island using the relative spring gravimeter LaCoste and Romberg gPhone-054. On 15 September 2011, an observed gravity decrease of 45 μGal, associated with the southward migration of seismic epicenters, is consistent with a lateral magma migration that occurred beneath the volcanic edifice, an apparently clear precursor of the eruption that took place 25 days later on 10 October 2011. High-frequency gravity signals also appeared on 6-11 October 2011, pointing to an occurring interaction between a magmatic intrusion and the ocean floor. These important gravity changes, with amplitudes varying from 10 to -90 μGal, during the first 3 days following the onset of the eruption are consistent with the northward migration of the eruptive focus along an active eruptive fissure. An apparent correlation of gravity variations with body tide vertical strain was also noted, which could indicate that concurrent tidal triggering occurred during the initial stage of the eruption.

  20. Volcanic alert system (VAS) developed during the 2011-2014 El Hierro (Canary Islands) volcanic process

    Science.gov (United States)

    García, Alicia; Berrocoso, Manuel; Marrero, José M.; Fernández-Ros, Alberto; Prates, Gonçalo; De la Cruz-Reyna, Servando; Ortiz, Ramón

    2014-06-01

    The 2011 volcanic unrest at El Hierro Island illustrated the need for a Volcanic Alert System (VAS) specifically designed for the management of volcanic crises developing after long repose periods. The VAS comprises the monitoring network, the software tools for analysis of the monitoring parameters, the Volcanic Activity Level (VAL) management, and the assessment of hazard. The VAS presented here focuses on phenomena related to moderate eruptions, and on potentially destructive volcano-tectonic earthquakes and landslides. We introduce a set of new data analysis tools, aimed to detect data trend changes, as well as spurious signals related to instrumental failure. When data-trend changes and/or malfunctions are detected, a watchdog is triggered, issuing a watch-out warning (WOW) to the Monitoring Scientific Team (MST). The changes in data patterns are then translated by the MST into a VAL that is easy to use and understand by scientists, technicians, and decision-makers. Although the VAS was designed specifically for the unrest episodes at El Hierro, the methodologies may prove useful at other volcanic systems.

  1. Contrasting recruitment seasonality of sea urchin species in Gran Canaria, Canary Islands (eastern Atlantic

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    S. GARCIA-SANZ

    2014-09-01

    Full Text Available Despite sea-urchins can play an important role affecting the community structure of subtidal bottoms, factors controlling the dynamics of sea-urchin populations are still poorly understood. We assessed the seasonal variation in recruitment of three sea-urchin species (Diadema africanum, Paracentrotus lividus and Arbacia lixula at Gran Canaria Island (eastern Atlantic via monthly deployment of artificial collectors throughout an entire annual cycle on each of four adjacent habitat patches (seagrasses, sandy patches, ‘urchin-grazed’ barrens and macroalgal-dominated beds within a shallow coastal landscape. Paracentrotus lividus and A. lixula had exclusively one main recruitment peak in late winter-spring. Diadema africanum recruitment was also seasonal, but recruits appeared in late summer-autumn, particularly on ‘urchin-grazed’ barrens with large abundances of adult conspecifics. In conclusion, this study has demonstrated non-overlapping seasonal recruitment patterns of the less abundant species (P. lividus and A. lixula with the most conspicuous species (D. africanum in the study area.

  2. Long-term aerosol measurements in Gran Canaria, Canary Islands: Particle concentration, sources and elemental composition

    Science.gov (United States)

    Gelado-Caballero, MaríA. D.; López-GarcíA, Patricia; Prieto, Sandra; Patey, Matthew D.; Collado, Cayetano; HéRnáNdez-Brito, José J.

    2012-02-01

    There are very few sets of long-term measurements of aerosol concentrations over the North Atlantic Ocean, yet such data is invaluable in quantifying atmospheric dust inputs to this ocean region. We present an 8-year record of total suspended particles (TSP) collected at three stations on Gran Canaria Island, Spain (Taliarte at sea level, Tafira 269 m above sea level (a.s.l.) and Pico de la Gorra 1930 m a.s.l.). Using wet and dry deposition measurements, the mean dust flux was calculated at 42.3 mg m-2 d-1. Air mass back trajectories (HYSPLIT, NOAA) suggested that the Sahara desert is the major source of African dust (dominant during 32-50% of days), while the Sahel desert was the major source only 2-10% of the time (maximum in summer). Elemental composition ratios of African samples indicate that, despite the homogeneity of the dust in collected samples, some signatures of the bedrocks can still be detected. Differences were found for the Sahel, Central Sahara and North of Sahara regions in Ti/Al, Mg/Al and Ca/Al ratios, respectively. Elements often associated with pollution (Pb, Cd, Ni, Zn) appeared to share a common origin, while Cu may have a predominantly local source, as suggested by a decrease in the enrichment factor (EF) of Cu during dust events. The inter-annual variability of dust concentrations is investigated in this work. During winter, African dust concentration measurements at the Pico de la Gorra station were found to correlate with the North Atlantic Oscillation (NAO) index.

  3. Characterization of fibers as rockwool for insulation obtained from canary islands basalts

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    Cáceres, J. M.

    1996-06-01

    Full Text Available Glass fibers in the shape of wool were obtained at laboratory scale from three samples of basaltic rocks from the Tenerife Island. The rockwool is widely used as thermal and acoustical insulation. The ability of these rocks to be fiberized was studied by means of the viscosity curves and can be quite improved by adding calcium and magnesium. The experimental fibers obtained from the rocks directly or mixed with either CaCO3 or CaMg(CO32 ye characterized in terms of chemical composition, microstructure and thermal and mechanical properties. These properties were compared with the ones determined for four commercial samples of rockcwool, founding that they are very close. This gives good prospects to these fibers from Canarian basalts as insulation material.

    Se ha obtenido fibra de vidrio en forma de lana, a escala de laboratorio, a partir de tres muestras de rocas basálticas de la Isla de Tenerife. La lana de roca se emplea extensamente como aislamiento térmico y acústico. La aptitud de estas rocas para su fibrado, estudiada mediante las curvas de viscosidad, mejora considerablemente con la adición de calcio y magnesio. Las fibras experimentales, obtenidas tanto a partir de las rocas directamente, como mezcladas en diferentes proporciones con CaCO3 o CaMg(CO32, se han caracterizado en lo referente a la composición química, la microestructura y propiedades térmicas y mecánicas. Así mismo, se han comparado estas propiedades con las determinadas para cuatro muestras comerciales de lana de roca, permitiendo comprobar que son bastante semejantes, lo que hace prever unas buenas cualidades para estas fibras de basaltos canarios en aplicaciones de aislamiento térmico y acústico.

  4. Causes and mobility of large volcanic landslides: application to Tenerife, Canary Islands

    Science.gov (United States)

    Hürlimann, M.; Garcia-Piera, J. O.; Ledesma, A.

    2000-12-01

    Giant volcanic landslides are one of the most hazardous geological processes due to their volume and velocity. Since the 1980 eruption and associated debris avalanche of Mount St. Helens hundreds of similar events have been recognised worldwide both on continental volcanoes and volcanic oceanic islands. However, the causes and mobility of these enormous mass movements remain unresolved. Tenerife exhibits three voluminous subaerial valleys and a wide offshore apron of landslide debris produced by recurrent flank failures with ages ranging from Upper Pliocene to Middle Pleistocene. We have selected the La Orotava landslide for analysis of its causes and mobility using a variety of simple numerical models. First, the causes of the landslide have been evaluated using Limit Equilibrium Method and 2D Finite Difference techniques. Conventional parameters including hydrostatic pore pressure and material strength properties, together with three external processes, dike intrusion, caldera collapse and seismicity, have been incorporated into the stability models. The results indicate that each of the external mechanism studied is capable of initiating slope failures. However, we propose that a combination of these processes may be the most probable cause for giant volcanic landslides. Second, we have analysed the runout distance of the landslide using a simple model treating both the subaerial and submarine parts of the sliding path. The effect of the friction coefficient, drag forces and hydroplaning has been incorporated into the model. The results indicate that hydroplaning particularly can significantly increase the mobility of the landslide, which may reach runout distances greater than 70 km. The models presented are not considered definite and have mainly a conceptual purpose. However, they provide a physical basis from which to better interpret these complex geologic phenomena and should be taken into account in the prediction of future events and the assessment of

  5. Implementation of Response to Intervention (RtI) Model in Spain: an example of a collaboration between Canarian universities and the department of education of the Canary Islands.

    Science.gov (United States)

    Jiménez, Juan E; Rodríguez, Cristina; Crespo, Patricia; González, Desirée; Artiles, Ceferino; Alfonso, Miguel

    2010-11-01

    The purpose of this study was to examine the effectiveness of second tier intervention at-risk readers within the context of a Response to Intervention approach. The study was conducted in the Canary Islands (Spain), directed by research team ¨Dificultades de Aprendizaje, Psicolingüística y Nuevas Tecnologías¨ (DEA&NT) from University of La Laguna, and supported by the Government of the Canary Islands. A sample of 1.123 Spanish children from fourteen schools districts were given the Spanish adaptation of The Hong Kong Specific Learning Difficulties Behavior Checklist and children who scored at or above the 75th percentile on the test were classified as "at risk" for early reading difficulties. Half of the students were randomly assigned to a project-based intervention condition where they received small group supplementary intervention for 30 minutes daily using the Prevención de las Dificultades Específicas de Aprendizaje (PREDEA) curriculum from mid to late December and continued until mid June. The other half received whatever remedial services were available at their schools. Results indicated that children who received the PREDEA curriculum had higher scores on the Early Grade Reading Assessment Test (EGRA) on initial sound identification, listening comprehension, letter sound knowledge and oral reading fluency compared to the control group.

  6. Characterization of six microsatellite loci in Myrica faya (Myricaceae and cross amplification in the endangered endemic M. rivas-martinezii in Canary Islands, Spain

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    Miguel A. González-Pérez

    2009-01-01

    Full Text Available Six novel polymorphic microsatellite markers were isolated from enriched libraries in Myrica faya Ait., recently renamed Morella faya , (fayatree, firetree, or firebush in order to examine the genetic diversity in natural populations. Also, test cross-specific amplification and genetic diversity in Myrica rivas-martinezii, which is endemic on the Canary islands. Microsatellite loci were screened in 225 individuals of both species from different islands of the Canarian archipelago. All markers were successfully amplified from both Myrica species, with an average number of 6.5 and 9.3 alleles per locus in M. rivas-martinezii and M. faya , respectively. There was no evidence for linkage disequilibrium between loci, and the probability of null alleles ranged from 0.01 to 0.17.

  7. Petrological and geochemical Highlights in the floating fragments of the October 2011 submarine eruption offshore El Hierro (Canary Islands): Relevance of submarine hydrothermal processes

    Science.gov (United States)

    Rodriguez-Losada, Jose A.; Eff-Darwich, Antonio; Hernandez, Luis E.; Viñas, Ronaldo; Pérez, Nemesio; Hernandez, Pedro; Melián, Gladys; Martinez-Frías, Jesús; Romero-Ruiz, M. Carmen; Coello-Bravo, Juan Jesús

    2015-02-01

    This paper describes the main physical, petrological and geochemical features of the floating fragments that were emitted in the initial stages of the 2011-2012 submarine eruption off the coast of the Canarian island of El Hierro, located 380 km from the Northwest African Coast. It attempts to assess the potential of radiometric analyses to discern the intriguing origin of the floating fragments and the differences between their constituent parts. In this regard, the material that conforms the core of the fragments contains the largest concentration of uranium (U) ever found in volcanic rocks of the Canary Islands. This enrichment in U is not found in the content of thorium (Th), hence the floating fragments have an unusual U/Th ratio, namely equal to or larger than 3. Although the origin of this material is under discussion, it is proposed that the enrichment in U is the result of hydrothermal processes.

  8. Evolutive and regressive soil sequences for characterization of soils in laurel forest (Tenerife, Canary Islands

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    José Asterio Guerra-García

    2014-03-01

    Full Text Available Soil degradation processes have achieved the recognition of a global environmental problem in recent years. It has been suggested by various international forums and organizations that in order to adequately establish methods to combat land degradation, it is necessary to evaluate this degradation locally and at a detailed scale. The evaluation of soil degradation of natural ecosystems at a detailed scale requires the definition of standards to which to compare this degradation. To define these standards and properly handle the processes that give rise to variations in soil quality and degradation, it is necessary to establish in some detail the pedogenic processes that have or have not taken place in a particular area and which lead to the formation of a mature soil. A mature soil should be considered as standard in these situations and, therefore, a non-degraded soil. This paper presents the possible evolutive and regressive sequences of soil, and provides some examples of using this methodology to evaluate the degradation of the same in the Monteverde of the island of Tenerife. It also presents some physical, chemical and mineralogical properties of climacic mature soils, degraded soils and low quality soils, and examines their similarities and differences in this bioclimatic environment and on different parent materials. Thus it is observed that the main processes of degradation in these areas are related to plant cover modifications that lead to the decreasing protection of the soil surface, which results in the long term, in the onset of degradation processes such as water erosion, biological degradation, loss of andic properties, compaction and sealing and crusting surface, loss of water retention capacity, illuviation, etc. Climacic soils that can be found in areas of steep lava flows are Leptosols, while gently sloping areas are Cambisols and Andosols. On pyroclastic materials there are vitric Andosols and andic Andosols according to

  9. On the predictability of volcano-tectonic events by low frequency seismic noise analysis at Teide-Pico Viejo volcanic complex, Canary Islands

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    M. Tárraga

    2006-01-01

    Full Text Available The island of Tenerife (Canary Islands, Spain, is showing possible signs of reawakening after its last basaltic strombolian eruption, dated 1909 at Chinyero. The main concern relates to the central active volcanic complex Teide - Pico Viejo, which poses serious hazards to the properties and population of the island of Tenerife (Canary Islands, Spain, and which has erupted several times during the last 5000 years, including a subplinian phonolitic eruption (Montaña Blanca about 2000 years ago. In this paper we show the presence of low frequency seismic noise which possibly includes tremor of volcanic origin and we investigate the feasibility of using it to forecast, via the material failure forecast method, the time of occurrence of discrete events that could be called Volcano-Tectonic or simply Tectonic (i.e. non volcanic on the basis of their relationship to volcanic activity. In order to avoid subjectivity in the forecast procedure, an automatic program has been developed to generate forecasts, validated by Bayes theorem. A parameter called 'forecast gain' measures (and for the first time quantitatively what is gained in probabilistic terms by applying the (automatic failure forecast method. The clear correlation between the obtained forecasts and the occurrence of (Volcano-Tectonic seismic events - a clear indication of a relationship between the continuous seismic noise and the discrete seismic events - is the explanation for the high value of this 'forecast gain' in both 2004 and 2005 and an indication that the events are Volcano-Tectonic rather than purely Tectonic.

  10. A multisystemic Acanthamoeba infection in a dog in Tenerife, Canary Islands, Spain.

    Science.gov (United States)

    Valladares, María; Reyes-Batlle, María; Mora-Peces, Inmaculada; Martín-Navarro, Carmen M; López-Arencibia, Atteneri; Dorta-Gorrín, Alexis; Comyn-Afonso, Estefanía; Martínez-Carretero, Enrique; Maciver, Sutherland K; Piñero, José E; Valladares, Basilio; Lorenzo-Morales, Jacob

    2014-10-15

    A 22-month-old male Spanish water dog was hospitalized after its physical examination revealed fever and movement difficulty. After 24h, the dog was found to have a high fever (39.5 °C) and was treated empirically with doxycycline/ciprofloxacin. At 48 h, after submission the fever rose to 41 °C and the animal presented with a stiff neck and dehydration. Peripheral blood and cerebrospinal fluid (CSF) were sampled and trophozoites with an Acanthamoeba-like morphology were observed in the CSF. PCR specific for Acanthamoeba, Naegleria fowleri and Balamuthia mandrillaris were performed and the CSF sample found positive for Acanthamoeba. Lungs, kidney, liver and spleen samples were collected post mortem. All collected organ samples were positive for Acanthamoeba by PCR, thus confirming a multisystemic infection. Water samples taken at a suspected site of infection yielded an almost identical PCR fragment to those of the clinical samples, indicating that this was probably where the infection originated. This is the first report of a fatal case of Acanthamoeba disseminated infection in a dog in Spain.

  11. Genetic characterization and molecular identification of the bloodmeal sources of the potential bluetongue vector Culicoides obsoletus in the Canary Islands, Spain

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    Martínez-de la Puente Josué

    2012-07-01

    Full Text Available Abstract Background Culicoides (Diptera: Ceratopogonidae biting midges are vectors for a diversity of pathogens including bluetongue virus (BTV that generate important economic losses. BTV has expanded its range in recent decades, probably due to the expansion of its main vector and the presence of other autochthonous competent vectors. Although the Canary Islands are still free of bluetongue disease (BTD, Spain and Europe have had to face up to a spread of bluetongue with disastrous consequences. Therefore, it is essential to identify the distribution of biting midges and understand their feeding patterns in areas susceptible to BTD. To that end, we captured biting midges on two farms in the Canary Islands (i to identify the midge species in question and characterize their COI barcoding region and (ii to ascertain the source of their bloodmeals using molecular tools. Methods Biting midges were captured using CDC traps baited with a 4-W blacklight (UV bulb on Gran Canaria and on Tenerife. Biting midges were quantified and identified according to their wing patterns. A 688 bp segment of the mitochondrial COI gene of 20 biting midges (11 from Gran Canaria and 9 from Tenerife were PCR amplified using the primers LCO1490 and HCO2198. Moreover, after selected all available females showing any rest of blood in their abdomen, a nested-PCR approach was used to amplify a fragment of the COI gene from vertebrate DNA contained in bloodmeals. The origin of bloodmeals was identified by comparison with the nucleotide-nucleotide basic alignment search tool (BLAST. Results The morphological identification of 491 female biting midges revealed the presence of a single morphospecies belonging to the Obsoletus group. When sequencing the barcoding region of the 20 females used to check genetic variability, we identified two haplotypes differing in a single base. Comparison analysis using the nucleotide-nucleotide basic alignment search tool (BLAST showed that both

  12. Rhizobia from Lanzarote, the Canary Islands, that nodulate Phaseolus vulgaris have characteristics in common with LMW RNA group II Sinorhizobium meliloti of Medicago, Melilotus and Trigonella from soils of mainland Spain

    Science.gov (United States)

    Several isolates from nodules of Phaseolus vulgaris grown in soil of Lanzarote, an island of the Canaries, had electrophoretic LMW RNA patterns identical with a less common pattern within S. meliloti (assigned as group II) obtained from nodules of alfalfa and alfalfa-related legumes grown in northe...

  13. Xenophobic discourse and agenda-setting. A case study in the press of the Canary Islands (Spain

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    Rodrigo F. Rodríguez Borges, Ph. D.

    2010-01-01

    Full Text Available Since its formulation by McCombs and Shaw in the 70s, the concept of agenda-setting has proved to be of relevant heuristic value to explore the relationship between the media agenda and the public agenda and the processes of transference between them both. Taking this idea as a reference and basing on the tools of the analysis discourse by Van Dijk, this article shows the strategy of informative dosage developed by the newspaper El Día from Tenerife, Canary Islands (Spain to turn the irregular immigration into the main issue in the civil agenda. The case study is focused on the support given by the newspaper to the call for a demonstration supporting a law of residence as the solution to the arrival of immigrants to the islands. We identified the writing units addressed to the demonstration call, the deliberate chronological sequence used to inform the readers and the editorial declarations supporting the initiative. The analysis lets us appreciate a paradigmatic example of the power of the media to set the political agenda and take in the political parties and the main institutions.Resumen: Desde su formulación en la década de los 70 por McCombs y Shaw, el concepto de 'fijación de agenda' ha demostrado un relevante valor heurístico para explorar las relaciones entre la agenda de los medios y la agenda pública y los procesos de transferencia entre ambas esferas. Tomando como referencia esta noción y apoyándose en las herramientas del análisis del discurso desarrolladas por Van Dijk, este artículo muestra la estrategia de dosificación informativa seguida por el periódico El Día, de Tenerife, Islas Canarias (España para convertir la inmigración irregular en una cuestión central en la agenda ciudadana. El estudio de caso se centra en el apoyo prestado por el diario a la convocatoria de una manifestación ciudadana en favor de una ley de residencia como solución a la llegada de inmigrantes a Canarias. En el estudio se procedió a

  14. Parasites of Columba livia (Aves: Columbiformes) in Tenerife (Canary Islands) and their role in the conservation biology of the laurel pigeons.

    Science.gov (United States)

    Foronda, P; Valladares, B; Rivera-Medina, J A; Figueruelo, E; Abreu, N; Casanova, J C

    2004-09-01

    The prevalence and intensity of the parasites from 50 wild doves (Columba livia) from the city of Santa Cruz de Tenerife, in the island of Tenerife (Canary Archipelago), were studied. The following ectoparasites were found in apparently healthy pigeons (prevalences are shown in percentage (%) and mean intensities with their standard deviations): the acari Dermanyssus gallinae (De Geer, 1778) (6, 241.0 +/- 138.9) and Tinaminyssus melloi Fain, 1962 (10%, 218.3 +/- 117.3); the louses, Columbicola columbae Linnaeus, 1758 (100%, 111.4 +/- 76.8) and Campanulotes bidentatus Scopoli, 1763 (94%, 48.4 +/- 26.6); and the pigeon fly, Pseudolynchia canariensis Macquart, 1839 (36%, 6.2 +/- 1.6). The endoparasites we found were: a haemoprotozoan species, Haemoproteus columbae Kruze, 1890 (82%, 14.8 +/- 10.3 per 1000); coccidian oocysts, Eimeria sp. (50%, 0.2 x 10(3) +/- 1.7 x 10(3) per gr); a cestode species Raillietina micracantha (Fuhrmann, 1909) López Neyra, 1947 (44%, 12.3 +/- 9.4); and four nematode species, Tetrameres (Tetrameres) fissispina (Diesing, 1861) Travassos, 1915 (4%, 99.5 +/- 34.1), Synhimantus (Dispharynx) spiralis (Molin, 1858) (8%, 46.8 +/- 11.6), Ascaridia columbae (Gmelin, 1790) Travassos, 1913 (40%, 8.4 +/- 8.8) and Aonchotheca sp. (18%, 6.0 +/- 3.1). Several species detected in our study can be pathogens for C. bollii and C. junoniae, which are endemic pigeons of the Canary Islands, considered endangered species. Parasites (ectoparasites, protozoa and helminths) of C. livia found in Tenerife and others from wild and farm birds in the island were considered as healthy controls.

  15. Parasites of Columba livia (Aves: Columbiformes in Tenerife (Canary Islands and their role in the conservation biology of the Laurel pigeons

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    Foronda P.

    2004-09-01

    Full Text Available The prevalence and intensity of the parasites from 50 wild doves (Columba livia from the city of Santa Cruz de Tenerife, in the island of Tenerife (Canary Archipelago, were studied. The following ectoparasites were found in apparently healthy pigeons (prevalences are shown in percentage (% and mean intensities with their standard deviations: the acari Dermanyssus gallinae (De Geer, 1778 (6 241 .0 ± 138.9 and Tinaminyssus melloi Fain, 1962 (10 %, 218.3 ± 117.3; the louses, Columbicola columbae Linnaeus, 1758 (100 %, 111.4 ± 76.8 and Campanulotes bidentatus Scopoli, 1763 (94 %, 48.4 ± 26.6; and the pigeon fly, Pseudolynchia canariensis Macquart, 1839 (36 %, 6.2 ± 1.6. The endoparasites we found, were: a haemoprotozoan species, Haemoproteus columbae Kruze, 1890 (82 %, 14.8 ± 10.3 per 1000; coccidian oocysts, Eimeria sp. (50 %, 0.2 x 103 ± 1.7 x 103 per gr; a cestode species Raillietina micracantha (Fuhrmann, 1909 López Neyra, 1947 (44 %, 12.3 ± 9.4; and four nematode species, Tetrameres (Tetrameres fissispina (Diesing, 1861 Travassos, 1915 (4 %, 99.5 ± 34,1, Synhimantus (Dispharynx spiralis (Molin, 1858 (8 %, 46. 8 ± 11.6, Ascaridia columbae (Gmelin, 1790 Travassos, 1913 (40 %, 8.4 ± 8.8 and Aonchotheca sp. (18 %, 6.0 ± 3.1. Several species detected in our study can be pathogens for C. bollii and C. junoniae, which are endemic pigeons of the Canary Islands, considered endangered species. Parasites (ectoparasites, protozoa and helminths of C. livia found in Tenerife and others from wild and farm birds in the island were considered as healthy controls.

  16. Application of emulsion imaging system for cosmic-ray muon radiography to explore the internal structure of Teide and Cumbre Vieja volcanoes in the Canary Islands, Spain

    Science.gov (United States)

    Hernández, Iñigo; Hernández, Pedro; Pérez, Nemesio; Tanaka, Hiroyuki; Miyamoto, Seygo; Barrancos, José; Padrón, Eleazar

    2013-04-01

    The internal structure of volcanoes, especially in their up per part, is product of past eruptions. Therefore, the knowledge of the internal structure of a volcano is of great importance for understanding its behaviour and to forecast the nature and style of the next eruptions. For these reasons, during past years scientists have made a big effort to investigate the internal structure of the volcanoes with different geophysical techniques, including deep drilling, passive and active seismic tomography, geoelectrics and magnetotellurics and gravimetry. One of the limits of conventional geophysical methods is the spatial resolution, which typically ranges between some tens of meters up to 1 km. In this sense, the radiography of active volcanoes based on natural muons, even if limited to the external part of the volcano, represents an important tool for investigating the internal structure of a volcano at higher spatial resolution (Macedonio and Martini, 2009). Moreover, muon radiography is able to resolve density contrasts of the order of 1-3%, significantly greater than the resolution obtained with conventional methods. As example, the experiment of muon radiography carried out at Mt. Asama volcano by Tanaka et al., 2007, allowed the reconstruction of the density map of the cone and detection of a dense region that corresponds to the position and shape of a lava deposit created during the last eruption in 2004. In the framework of a research project financed by the Canary Agency of Research, Innovation and Information Society, we will implement muon measurements at Teide volcano in Tenerife Island and Cumbre Vieja volcano in La Palma Island, Canary Islands, to radiographically image the subsurface structure of these two volcanic edifices. The data analysis will involve the study both of the shallow structure of both volcanoes and of the requirements for the implementation of the muon detectors. Both Cumbre Vieja and Teide are two active volcanoes that arouse great

  17. of Canary Islands

    Directory of Open Access Journals (Sweden)

    Eduardo Parra López

    2006-01-01

    Full Text Available La ultraperiferia añade a los problemas inherentes a la insularidad los derivados de la lejanía respecto a los principales centros de aprovisionamiento, la considerable escasez de recursos, la fragmentación del territorio, y por tanto, de los mercados. En las últimas décadas se ha ido tomando conciencia del impacto de la ultraperiferia sobre el desarrollo de las regiones y estados insulares. La ultraperiferia es un atributo geográfico que condiciona las opciones de desarrollo y el tipo de especialización de las economías, afecta a la competitividad y a las estrategias empresariales. El agroturismo es una de las actividades que está adquiriendo mayor relevancia en el marco de la diversificación de las explotaciones agrarias, agropecuarias y del turismo. Por ello, la necesidad de activar económicamente las zonas rurales de territorios insulares ultraperiféricos, así como la valorización de las producciones agrarias y agropecuarias vinculadas a la actividad turística, se presentan como elementos vitales para estrategias de diversificación, transformación y mejora de la competitividad y calidad de las mismas. El presente trabajo tiene como objetivo analizar los cambios y el posible impacto que supone la incorporación del agroturismo como una alternativa al turismo de sol y playa, de incremento de rentas de las familias, del desarrollo rural y de nuevas formas de turismo. Se pretende establecer un análisis estratégico del agroturismo, analizar el lado de la oferta y demanda, para sentar la base de las razones de fomentar esta actividad.

  18. Atmospheric corrosion in subtropical areas: XRD and electrochemical study of zinc atmospheric corrosion products in the province of Santa Cruz de Tenerife (Canary Islands, Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Morales, J. [Departamento de Quimica Fisica, Universidad de La Laguna, 38071 La Laguna, Tenerife (Spain)]. E-mail: jmorales@ull.es; Diaz, F. [Departamento de Quimica Fisica, Universidad de La Laguna, 38071 La Laguna, Tenerife (Spain); Hernandez-Borges, J. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Universidad de La Laguna, 38071 La Laguna, Tenerife (Spain); Gonzalez, S. [Departamento de Quimica Fisica, Universidad de La Laguna, 38071 La Laguna, Tenerife (Spain)

    2006-02-15

    In the present paper, zinc sheets have been exposed for 4 years to the action of different atmospheres in 35 test sites located in the province of Santa Cruz de Tenerife, Canary Islands, Spain. Corrosion products formed on the surface of the samples have been identified by means of X-ray diffraction (XRD) for the first and second year of exposure. Zincite, hydrozincite, simonkolleite, zinc chlorohydroxysulphate, zinc oxysulphate and zinc hydroxysulphate have been identified in the test sheets. Preliminary results of an electrochemical study of the breakdown potential of zinc samples are also presented in order to test the protective effect of the film formed on the surface of the samples. It was found that the protective effect of this film increases linearly with exposure time.

  19. Quantification of ozone uptake at the stand level in a Pinus canariensis forest in Tenerife, Canary Islands: an approach based on sap flow measurements.

    Science.gov (United States)

    Wieser, Gerhard; Luis, Vanessa C; Cuevas, Emilio

    2006-04-01

    Ozone uptake was studied in a pine forest in Tenerife, Canary Islands, an ecotone with strong seasonal changes in climate. Ambient ozone concentration showed a pronounced seasonal course with high concentrations during the dry and warm period and low concentrations during the wet and cold season. Ozone uptake by contrast showed no clear seasonal trend. This is because canopy conductance significantly decreased with soil water availability and vapour pressure deficit. Mean daily ozone uptake averaged 1.9 nmol m(-2) s(-1) during the wet and cold season, and 1.5 nmol m(-2) s(-1) during the warm and dry period. The corresponding daily mean ambient ozone concentrations were 42 and 51 nl l(-1), respectively. Thus we conclude that in Mediterranean type forest ecosystems the flux based approach is more capable for risk assessment than an external, concentration based approach.

  20. The role of tourist destination in international students’ choice of academic center: the case of erasmus programme in the Canary Islands

    Directory of Open Access Journals (Sweden)

    Francisco J. García\\u2011Rodríguez

    2015-01-01

    Full Text Available The study measures the importance of the university and the tourist destination factors in the international students´ choice of placement for their studies and their further satisfaction. Using a sample from the Erasmus Exchange Programme in the Canary Islands, one of the main European tourist destinations, the results show the potential that academic tourism could have for the host destination and in particular, the importance of the attraction factors linked to the destination rather than those associated with the academic center. Hence, to take advantage of this potential, it is essential to develop collaborative strategies among the managers of the destination and those responsible for the academic center analyzed.

  1. Assessment of the abiotic and biotic effects of sodium metabisulphite pulses discharged from desalination plant chemical treatments on seagrass (Cymodocea nodosa) habitats in the Canary Islands.

    Science.gov (United States)

    Portillo, E; Ruiz de la Rosa, M; Louzara, G; Ruiz, J M; Marín-Guirao, L; Quesada, J; González, J C; Roque, F; González, N; Mendoza, H

    2014-03-15

    Reverse osmosis membranes at many desalination plants are disinfected by periodic shock treatments with sodium metabisulphite, which have potentially toxic effects to the environment for marine life, although no empirical and experimental evidence for this is yet available. The aim of this study was to characterise for the first time, the physico-chemical modification of the marine environment and its biological effects, caused by hypersaline plumes during these membrane cleaning treatments. The case study was the Maspalomas II desalination plant, located in the south of Gran Canaria (Canary Islands, Spain). Toxicity bioassays were performed on marine species characteristic for the infralittoral soft bottoms influenced by the brine plume (Synodus synodus and Cymodocea nodosa), and revealed a high sensitivity to short-term exposure to low sodium metabisulphite concentrations. The corrective measure of incorporating a diffusion system with Venturi Eductors reduced nearly all the areas of influence, virtually eliminating the impact of the disinfectant.

  2. Protected areas in the Atlantic facing the hazards of micro-plastic pollution: first diagnosis of three islands in the Canary Current.

    Science.gov (United States)

    Baztan, Juan; Carrasco, Ana; Chouinard, Omer; Cleaud, Muriel; Gabaldon, Jesús E; Huck, Thierry; Jaffrès, Lionel; Jorgensen, Bethany; Miguelez, Aquilino; Paillard, Christine; Vanderlinden, Jean-Paul

    2014-03-15

    Coastal zones and the biosphere as a whole show signs of cumulative degradation due to the use and disposal of plastics. To better understand the manifestation of plastic pollution in the Atlantic Ocean, we partnered with local communities to determine the concentrations of micro-plastics in 125 beaches on three islands in the Canary Current: Lanzarote, La Graciosa, and Fuerteventura. We found that, in spite of being located in highly-protected natural areas, all beaches in our study area are exceedingly vulnerable to micro-plastic pollution, with pollution levels reaching concentrations greater than 100 g of plastic in 1l of sediment. This paper contributes to ongoing efforts to develop solutions to plastic pollution by addressing the questions: (i) Where does this pollution come from?; (ii) How much plastic pollution is in the world's oceans and coastal zones?; (iii) What are the consequences for the biosphere?; and (iv) What are possible solutions?

  3. Levels and profiles of POPs (organochlorine pesticides, PCBs, and PAHs) in free-ranging common bottlenose dolphins of the Canary Islands, Spain.

    Science.gov (United States)

    García-Alvarez, Natalia; Martín, Vidal; Fernández, Antonio; Almunia, Javier; Xuriach, Aina; Arbelo, Manuel; Tejedor, Marisa; Boada, Luis D; Zumbado, Manuel; Luzardo, Octavio P

    2014-09-15

    The effect of anthropogenic pollution in marine mammals worldwide has become an important issue due to the high concentrations found in many areas. The present study represents the first report of pollutants in free-ranging cetaceans from the Canary Islands, where there are 12 marine Special Areas of Conservation (SACs), because of the presence of bottlenose dolphins (Tursiops truncatus). We selected this resident population of dolphins as a bioindicator to gain knowledge concerning the toxicological status of the cetaceans of this protected area. In 64 biopsy samples of live free-ranging animals sampled from 2003 to 2011, we determined the concentrations of 18 polychlorinated biphenyls (PCBs), 23 organochlorine pesticides (OCPs) and 16 polycyclic aromatic hydrocarbons (PAHs). We found high levels of many of these pollutants, and some of them were detectable in 100% of the samples. The median value for ∑OCPs was 57,104 ng g(-1) lipid weight (lw), and the dichlorodiphenyldichloroethylene (p,p'-DDE) accounted for 70% of this amount. Among PCBs, congeners 180, 153 and 138 were predominant (82% of ∑PCBs; median = 30,783 ng g(-1) lw). Concerning the analyzed PAHs, the total median burden was 13,598 ng g(-1) lw, and phenanthrene was the compound measured at the highest concentration followed by pyrene and by naphthalene. Surprisingly, we have found that organohalogen pollutants exhibit an upward trend in recent years of sampling. Thus, according to the guidelines outlined in the EU's Marine Strategy Framework Directive, further monitoring studies in Canary Islands are required to contribute to the conservation of the resident populations of marine mammals in this region.

  4. Precursory geophysical, geodetic and geochemical signatures of a new 2012 submarine eruption off the northwestern coast of El Hierro, Canary Islands, Spain

    Science.gov (United States)

    Pérez, Nemesio M.; Somoza, Luis; González de Vallejo, Luis; Sagiya, Takeshi; León, Ricardo; Hernández, Pedro A.; Biain, Ander; González, Francisco J.; Medialdea, Teresa; Gonzalez-Aller, Daniel; Sánchez de La Madrid, José Luis; Barrancos, José; Ibáñez, Jesús M.; Sumino, Hirochika

    2013-04-01

    Here we report precursory geophysical, geodetic, and geochemical signatures of a new submarine eruption off the northwestern coast of El Hierro, Canary Islands, which has been detected through acoustic imaging of submarine plumes on June 27, 2012, by the Spanish research vessel "Hespérides". Five distinct acoustic submarine plumes have been recognized in this area at water depths between 64 and 88 m along a submarine platform located in front of the Lomo Negro volcanic cone, northwestern of El Hierro. Submarine plums are characterized by vertical columns of high-amplitude values rising from seafloor. These acoustic imaging data clearly support a new submarine eruption in 2012 associated to the recent magmatic reactivation of El Hierro volcanic system. This new eruption event was preceded by several precursory signatures: (i) a sharp increase of the seismic energy release and the number of daily earthquakes of magnitude ≥ 2.5 on June 25, 2012, (ii) significant vertical and horizontal displacements observed at the Canary Islands GPS permanent network (Nagoya University-ITER-GRAFCAN) at El Hierro with uplifts up to 3 cm from June 25 to 26, 2012, (iii) an anomalous increase of the soil gas radon activity at HIE02, a geochemical station located in the northwestern of El Hierro, from the end of April until the beginning of June reaching peak values of 2.7 kBq/m3 on June 3, 2012, and (iv) the highest observed corrected value of 3He/4He ratio in ground waters (8,5 Ra) from San Simón well at the northwestern of El Hierro on June 16, 2012. These precursory signals have revealed important to improve and optimize the detection of early warning signals of volcanic unrest episodes at El Hierro.

  5. Análisis geográfico de las actuales relaciones comerciales entre Canarias y Marruecos / Geographic analysis of commercial relations between the Canary Islands and Morocco

    Directory of Open Access Journals (Sweden)

    Ramón Díaz Hernández

    2014-12-01

    Full Text Available En este trabajo formulamos como hipótesis de partida que Canarias, como frontera meridional de Europa, en un contexto de creciente internacionalización, tiene en los mercados africanos una gran baza histórica que desempeñar. Dado el interés general que este asunto suscita entre las ciencias sociales, se requiere abordarlo desde el análisis geográfico. Para cumplimentar este estudio se emplearon las estadísticas que ofrecen organismos oficiales como el Instituto Nacional de Estadística, Instituto Canario de Estadística, Agencia Estatal de la Administración Tributaria, Instituto de Comercio Exterior y entidades internacionales como la Conferencia de las Naciones Unidas para el Comercio y el Desarrollo (UNCTAD y la Organización Mundial del Comercio (OCM.In this work we formulate the hypothesis that the Canary Islands, as Europe’s southern border, must develop an important role in African markets, in a context of increasing internationalization. Because of the general interest in this issue within the social sciences, to address it from the geographic analysis is required. This study is based, on the one hand, on statistics provided by Spanish government agencies such as the National Statistics Institute, the Canary Institute of Statistics, the State Tax Administration Agency and the Institute of Foreign Trade and, on the other hand, by international entities such as the United Nations Conference for Trade and Development (UNCTAD and the World Trade Organization (WTO.

  6. Fractal Analysis of Enclaves as a New Tool for Estimating Rheological Properties of Magmas During Mixing: The Case of Montaña Reventada (Tenerife, Canary Islands)

    Science.gov (United States)

    Albert, Helena; Perugini, Diego; Martí, Joan

    2015-07-01

    The volcanic unit of Montaña Reventada on the island of Tenerife (Canary Islands, Spain) is an example of magma mingling and mixing in which the eruptive process was triggered by an intrusion of basanite into a phonolite magma chamber. The eruption started with emplacement of a basanitic scoria deposit followed by emplacement of a phonolitic lava flow characterized by the presence of mafic enclaves. These enclaves represent approximately 1 % of the outcrop and are basanitic, phono-tephritic and tephri-phonolitic in composition. The morphology of each enclave is different, varying from rounded to complex finger-like structures usually with cuspate terminations. In this study we quantified textural heterogeneity related to the enclaves generated by the mixing process and thus provided a new perspective on the 1100 Ad Montaña Reventada eruption. The textural study was performed by use of fractal geometry methods and the results show that the logarithm of the viscosity ratio between the phonolitic magma and the enclaves ranges between 0.39 and 0.81, with a mode at 0.49. This enables us to infer the water content is 2-2.5 wt% for the phonolitic magma and 1.5-2 wt% for the basanitic magma and the enclaves.

  7. Study on the formation and transport of ozone in relation to the air quality management and vegetation protection in Tenerife (Canary Islands).

    Science.gov (United States)

    Guerra, Juan-Carlos; Rodríguez, Sergio; Arencibia, M-Teresa; García, M-Dolores

    2004-09-01

    An experimental study on the formation and transport of ozone in ambient air was performed in Tenerife (Canary Islands) in order to investigate the processes affecting ozone levels and air quality. The special features of Tenerife (prevalence of the trade wind pattern (NE), orography and the specific location of the local ozone sources) permit to quantify the role of the 'long-range transport from northern latitudes' versus the 'formation and transport of ozone downwind of the main urban areas' of Tenerife. Levels of O(3), NO(2) and O(X) were monitored in different types of environments to achieve this purpose. The results showed that: (1) upwind of the urban areas ozone is mainly transported from the ocean by trade winds, (2) local ozone titration (by NO) and ozone replenishment from the ocean are the main causes of ozone variations in urban and suburban areas, and (3) photochemical ozone production occurs downwind of the urban areas. Photochemical production causes daylight O(3) and O(X) levels downwind of urban areas to be frequently (60% and 35% days/year, respectively) higher than upwind of the urban sites (O(3) and O(X) excess frequently in the range 5-20 ppbv). Due to the above processes, different daily ozone cycles occur in short distances (Tenerife.

  8. The potential pathogenicity of chlorhexidine-sensitive Acanthamoeba strains isolated from contact lens cases from asymptomatic individuals in Tenerife, Canary Islands, Spain.

    Science.gov (United States)

    Martín-Navarro, Carmen M; Lorenzo-Morales, Jacob; Cabrera-Serra, M Gabriela; Rancel, Fernando; Coronado-Alvarez, Nieves M; Piñero, José E; Valladares, Basilio

    2008-11-01

    Pathogenic strains of the genus Acanthamoeba are causative agents of a serious sight-threatening infection of the eye known as Acanthamoeba keratitis. The prevalence of this infection has risen in the past 20 years, mainly due to the increase in number of contact lens wearers. In this study, the prevalence of Acanthamoeba in a risk group constituted by asymptomatic contact lens wearers from Tenerife, Canary Islands, Spain, was evaluated. Contact lenses and contact lens cases were analysed for the presence of Acanthamoeba isolates. The isolates' genotypes were also determined after rDNA sequencing. The pathogenic potential of the isolated strains was subsequently established using previously described molecular and biochemical assays, which allowed the selection of three strains with high pathogenic potential. Furthermore, the sensitivity of these isolates against two standard drugs, ciprofloxacin and chlorhexidine, was analysed. As the three selected strains were sensitive to chlorhexidine, its activity and IC(50) were evaluated. Chlorhexidine was found to be active against these strains and the obtained IC(50) values were compared to the concentrations of this drug present in contact lens maintenance solutions. It was observed that the measured IC(50) was higher than the concentration found in these maintenance solutions. Therefore, the ineffectiveness of chlorhexidine-containing contact lens maintenance solutions against potentially pathogenic strains of Acanthamoeba is demonstrated in this study.

  9. Evaluation of changes in soil in the short and medium term due to a forest fire in the pine forest of Tenerife (Canary Islands, Spain

    Directory of Open Access Journals (Sweden)

    A. Hernández

    2013-09-01

    Full Text Available Forest fires lead to important changes in soil properties, which sometimes are non-reversible. In the Canary Islands, fires burn mainly Canarian pine (Pinus canariensis forests. This work evaluates the impact and evolution of some relevant physico-chemical and biological properties in burned soils affected in an area under Canarian pine forest in the NW of Tenerife. Four sites with different understory composition were selected, together with similar, unaffected neighboring areas as controls. In these areas, soil samples were gathered periodically (four times in each plot, along a period ranging between three months and three years after the fire. Samples were analyzed for different physico-chemical and biological parameters. The results showed increases in burned areas for pH, EC1: 5 and NH4+-N three months after the fire, without differences in further samplings. Increases were also found for the oxidizable carbon (Cox, total nitrogen (Ntot available cations, and water repellency. Furthermore, a considerable increase in soil respiration in the area affected by the fire was observed in the first sampling. However, this zone is also characterized by an initial decrease in the microbial biomass-linked organic C, and some enzymatic activities, particularly the phosphomonoesterase. In time, the enzymatic activities studied recovered progressively, without reaching the values measured at unburned areas.

  10. Changes in Al and Fe associated with amorphous soil minerals over one year after a wildfire at Pico Cho Marcial (Tenerife, Canary Islands, Spain

    Directory of Open Access Journals (Sweden)

    J. Notario

    2013-05-01

    Full Text Available Amorphous-linked Al, Fe and Si were determined both in burned and unburnt soil samples after a wildfire close to Pico Cho Marcial (Tenerife, Canary Islands, Spain that affected 7.1 ha of high mountain Teide broom scrub along four successive samplings held in September 2003 (three months after the wildfire, February 2004, June 2004 and October 2004. Soils in the area are Lithic Xerorthents, with a scarcely developed AC-type profile. The chemical elements under study were extracted using selective dissolutions (0.2M acid ammonium oxalate and 0.1N sodium pyrophosphate, and determined by Atomic Absorption Spectrophotometry. The average contents of total amorphous Al (oxalate-extractable and organo-metallic complexes-bound Al (pyrophosphate extractable were significantly higher in burned samples along the study. Also, the oxalate-extractable Al varied significantly along the different samplings, and so consequently did the Alp:Alox ratio. A progressive decrease in the Al:Si ratio in allophanes was also found throughout the study period. No differences were found for oxalate-extractable Fe, either between sample groups or samplings, which was also applicable to the (Alox+0.5Feox percentage.

  11. Ensifer meliloti bv. lancerottense establishes nitrogen-fixing symbiosis with Lotus endemic to the Canary Islands and shows distinctive symbiotic genotypes and host range.

    Science.gov (United States)

    León-Barrios, Milagros; Lorite, María José; Donate-Correa, Javier; Sanjuán, Juan

    2009-09-01

    Eleven strains were isolated from root nodules of Lotus endemic to the Canary Islands and they belonged to the genus Ensifer, a genus never previously described as a symbiont of Lotus. According to their 16S rRNA and atpD gene sequences, two isolates represented minority genotypes that could belong to previously undescribed Ensifer species, but most of the isolates were classified within the species Ensifer meliloti. These isolates nodulated Lotus lancerottensis, Lotus corniculatus and Lotus japonicus, whereas Lotus tenuis and Lotus uliginosus were more restrictive hosts. However, effective nitrogen fixation only occurred with the endemic L. lancerottensis. The E. meliloti strains did not nodulate Medicago sativa, Medicago laciniata Glycine max or Glycine soja, but induced non-fixing nodules on Phaseolus vulgaris roots. nodC and nifH symbiotic gene phylogenies showed that the E. meliloti symbionts of Lotus markedly diverged from strains of Mesorhizobium loti, the usual symbionts of Lotus, as well as from the three biovars (bv. meliloti, bv. medicaginis, and bv. mediterranense) so far described within E. meliloti. Indeed, the nodC and nifH genes from the E. meliloti isolates from Lotus represented unique symbiotic genotypes. According to their symbiotic gene sequences and host range, the Lotus symbionts would represent a new biovar of E. meliloti for which bv. lancerottense is proposed.

  12. Ultrastructural study of the spermatozoon of Taenia taeniaeformis (Batsch, 1786) (Cestoda, Cyclophyllidea, Taeniidae), an intestinal parasite of Felis catus from La Palma (Canary Islands, Spain).

    Science.gov (United States)

    Miquel, Jordi; Foronda, Pilar; Torres, Jordi; Swiderski, Zdzisław; Feliu, Carlos

    2009-06-01

    The ultrastructural characters of the mature spermatozoon of Taenia taeniaeformis are described by means of transmission electron microscopy. Materials were obtained from a naturally infected road-killed cat (Felis catus) from La Palma (Canary Islands, Spain). The mature spermatozoon of T. taeniaeformis is a filiform cell, which is tapered at both extremities and lacks mitochondria. It is characterised by the presence of (1) a single spirallised crested body about 140 nm thick, (2) a single axoneme of the 9+'1' pattern of trepaxonematan Platyhelminthes, (3) a twisted (40 degrees ) layer of submembranous cortical microtubules, (4) a periaxonemal sheath surrounding the axoneme, (5) transverse intracytoplasmic walls and (6) a spirallised nucleus encircling the axoneme. The mature spermatozoon of T. taeniaeformis is also characterised by the presence of an apical cone in its anterior extremity and by the disorganisation of the axoneme in its posterior extremity. The ultrastructural characters of the mature spermatozoon of T. taeniaeformis are compared with those of other cestodes studied to date, with particular emphasis on other representatives of the family Taeniidae.

  13. Phytochemical analysis and in vitro biological activity of three Hypericum species from the Canary Islands (Hypericum reflexum, Hypericum canariense and Hypericum grandifolium).

    Science.gov (United States)

    Zorzetto, Christian; Sánchez-Mateo, Candelaria C; Rabanal, Rosa M; Lupidi, Giulio; Petrelli, Dezemona; Vitali, Luca A; Bramucci, Massimo; Quassinti, Luana; Caprioli, Giovanni; Papa, Fabrizio; Ricciutelli, Massimo; Sagratini, Gianni; Vittori, Sauro; Maggi, Filippo

    2015-01-01

    In the present work we carried out a phytochemical and biological investigation on three Hypericum species, i.e. Hypericum reflexum, Hypericum canariense and Hypericum grandifolium, from the Canary Islands where they are traditionally used as diuretic, wound healing, vermifuge, sedative and antidepressive agents. The polar extracts of the top flowering aerial parts, prepared by Soxhlet apparatus using a methanol-acetone (1:1) extracting mixture, were analyzed by HPLC-DAD and HPLC-MS for the content of eight biomarkers such as hypericin, hyperforin, chlorogenic acid, rutin, hyperoside, isoquercitrin, quercitrin and quercetin, whereas the hydrodistilled essential oils were analyzed by GC-FID and GC-MS. The three Hypericum species had different results in both polar and volatile constituents, H. reflexum being the only one endowed with a small amount of naphtodianthrones (hypericin and pseudohypericin), and containing high levels of chlorogenic acid, rutin and volatile mono- and sesquiterpenes. After chemical characterization, all products were in vitro biologically assayed for antiproliferative activity on human tumor cell lines by MTT assay, for antioxidant potential by DPPH, ABTS and FRAP assays, and for antimicrobial activity by the agar disc diffusion and microdilution methods. Results revealed interesting bioactivities and differences between polar extracts and essential oils, with the former being endowed with significant antioxidant activity and the latter with comparable inhibition effects on the tumor cells (A375, MDA-MB 231 and HCT 116) to that of cisplatin.

  14. Applying Fractal Dimensions and Energy-Budget Analysis to Characterize Fracturing Processes During Magma Migration and Eruption: 2011-2012 El Hierro (Canary Islands) Submarine Eruption

    Science.gov (United States)

    López, Carmen; Martí, Joan; Abella, Rafael; Tarraga, Marta

    2014-07-01

    The impossibility of observing magma migration inside the crust obliges us to rely on geophysical data and mathematical modelling to interpret precursors and to forecast volcanic eruptions. Of the geophysical signals that may be recorded before and during an eruption, deformation and seismicity are two of the most relevant as they are directly related to its dynamic. The final phase of the unrest episode that preceded the 2011-2012 eruption on El Hierro (Canary Islands) was characterized by local and accelerated deformation and seismic energy release indicating an increasing fracturing and a migration of the magma. Application of time varying fractal analysis to the seismic data and the characterization of the seismicity pattern and the strain and the stress rates allow us to identify different stages in the source mechanism and to infer the geometry of the path used by the magma and associated fluids to reach the Earth's surface. The results obtained illustrate the relevance of such studies to understanding volcanic unrest and the causes that govern the initiation of volcanic eruptions.

  15. Probabilistic approach to decision making under uncertainty during volcanic crises. Retrospective analysis of the 2011 eruption of El Hierro, in the Canary Islands

    Science.gov (United States)

    Sobradelo, Rosa; Martí, Joan; Kilburn, Christopher; López, Carmen

    2014-05-01

    Understanding the potential evolution of a volcanic crisis is crucial to improving the design of effective mitigation strategies. This is especially the case for volcanoes close to densely-populated regions, where inappropriate decisions may trigger widespread loss of life, economic disruption and public distress. An outstanding goal for improving the management of volcanic crises, therefore, is to develop objective, real-time methodologies for evaluating how an emergency will develop and how scientists communicate with decision makers. Here we present a new model BADEMO (Bayesian Decision Model) that applies a general and flexible, probabilistic approach to managing volcanic crises. The model combines the hazard and risk factors that decision makers need for a holistic analysis of a volcanic crisis. These factors include eruption scenarios and their probabilities of occurrence, the vulnerability of populations and their activities, and the costs of false alarms and failed forecasts. The model can be implemented before an emergency, to identify actions for reducing the vulnerability of a district; during an emergency, to identify the optimum mitigating actions and how these may change as new information is obtained; and after an emergency, to assess the effectiveness of a mitigating response and, from the results, to improve strategies before another crisis occurs. As illustrated by a retrospective analysis of the 2011 eruption of El Hierro, in the Canary Islands, BADEMO provides the basis for quantifying the uncertainty associated with each recommended action as an emergency evolves, and serves as a mechanism for improving communications between scientists and decision makers.

  16. Organochlorine Pesticides Exposure and Bladder Cancer: Evaluation from a Gene-Environment Perspective in a Hospital-Based Case-Control Study in the Canary Islands (Spain).

    Science.gov (United States)

    Boada, L D; Henríquez-Hernández, L A; Zumbado, M; Almeida-González, M; Álvarez-León, E E; Navarro, P; Luzardo, O P

    2016-01-01

    The incidence of bladder cancer has increased significantly since the 1950s. Pesticide exposure has been linked with increasing bladder cancer incidence, although the evidence is inconclusive. However, most epidemiological studies did not evaluate the potential role played by the organochlorine pesticides, the most widely used pesticides in Western countries from the 1940s to the 1970s. Organochlorine pesticides were banned in the late 1970s because of their persistence in the environment and their carcinogenic and mutagenic effects. Organochlorine pesticides were employed in huge amounts in the Spanish archipelago of the Canary Islands; the authors, therefore, evaluated the role played by organochlorine pesticides exposure on bladder cancer. Serum levels of the most prevalent organochlorine pesticides used in the agriculture of these Islands (dichlorodiphenyltrichloroethane [p,p'-DDT], and its metabolites dichlorodiphenyldichloroethylene [p,p'-DDE] and dichlorodiphenyldichloroethane [p,p'-DDD], hexachlorobenzene, hexachlorocyclohexane isomers, aldrin, dieldrin, endrin, heptachlor, cis-chlordane, trans-chlordane, α- and β-endosulfan, endosulfan sulfate, methoxychlor, and mirex) were measured in 140 bladder cancer cases and 206 controls. GST-M1 and GST-T1 gene polymorphisms were genotyped by polymerase chain reaction (PCR)-based methods. These results showed that serum levels of organochlorine pesticides did not increase bladder cancer risk. On the contrary, total burden of hexachlorocyclohexanes was found to be negatively associated to bladder cancer (odds ratio [OR] = 0.929, 95% confidence interval [CI]: 0.865-0.997; P = .041). This effect disappeared when the distribution of the gluthathione S-transferase polymorphisms was introduced in the statistical model. These results indicate that organochlorine pesticides are not a risk factor for bladder cancer. However, these findings provide additional evidence of gene-environment interactions for organochlorine

  17. Essential and toxic metals in taros (Colocasia esculenta) cultivated in the Canary Islands (Spain): evaluation of content and estimate of daily intake.

    Science.gov (United States)

    Luis-González, Gara; Rubio, Carmen; Gutiérrez, Ángel; González-Weller, Dailos; Revert, Consuelo; Hardisson, Arturo

    2015-01-01

    Taros are a staple in the diet of many people around the world, and they are an excellent source of minerals. Monitoring the levels of metals in food provides basic information that is useful from the perspectives of safety, regulation, and nutrition. Forty-two samples of taros were randomly obtained from supermarkets, vegetable markets, and farmer's plots on the island of Tenerife (Canary Islands, Spain). The edible portion (pulp) was the only part considered for analysis. Flame atomic absorption spectrometry (FAAS) was used to determine the contents of Na, K, Ca, Mg, Cu, Fe, Mn, and Zn. The levels of Cr, Ni, Cd, and Pb were determined using graphite furnace atomic absorption spectrometry (GFAAS). Mean concentrations (mg/kg) were 565.6 Na, 2947 K, 231.4 Ca, 364.5 Mg, 1.224 Cu, 3.818 Fe, 1.408 Mn, 2.242 Zn, 0.044 Cr, 0.021 Ni, 0.003 Cd, and 0.006 Pb. The mean concentrations of Cd and Pb were well below the accepted European Commission limits (0.1 mg/kg weight for both metals, respectively). Daily consumption of taro (10.41 g taro/person/day) contributes to the dietary intake of essential metals and trace elements, mainly Mg (1.265% in adult women and 1.084% in adult men) and Cu (1.182% for adult men and women). The average daily intakes of Cd (0.031 μg/day) and Pb (0.062 μg/day) from taro were below the legislated respective tolerable weekly intakes (TWIs). Thus, the samples analyzed were considered safe to eat based on their metal concentrations and legislated allowable intakes.

  18. Continued implication of the banned pesticides carbofuran and aldicarb in the poisoning of domestic and wild animals of the Canary Islands (Spain).

    Science.gov (United States)

    Ruiz-Suárez, Norberto; Boada, Luis D; Henríquez-Hernández, Luis A; González-Moreo, Federico; Suárez-Pérez, Alejandro; Camacho, María; Zumbado, Manuel; Almeida-González, Maira; Del Mar Travieso-Aja, María; Luzardo, Octavio P

    2015-02-01

    Although nowadays the intentional poisoning of domestic and wild animals is a crime in EU, in the past the poison was used in rural areas of a number of European countries to kill animals that were considered harmful for human activities. In Spain evidences indicate that intentional poisonings continue to occur throughout the entire country nowadays. This situation seems to be of particular concern in the Canary Islands (Spain), where this study was performed. Our results confirmed that 225 animals were poisoned by pesticides over the study period (32 months; 2010-2013). The intentionality of the poisoning was confirmed in 117 cases. It has to be highlighted that the other 108 animals also died by pesticide poisoning, although the intentionality was only suspected. This incidence is currently the highest reported in any region from European Union. The pesticides carbofuran, bromadiolone, brodifacoum and aldicarb were the most frequently detected involved. Among the affected species, it has to be highlighted that endangered species are frequently affected in poisoning incidents. Notably, chemicals banned in the EU (carbofuran and aldicarb) were identified in approximately 75% of cases, and in almost 100% of baits, which suggests that these pesticides are still available to the population. Several circumstances may explain these results. Firstly, little control over the sale and possession of pesticide products, and the potential existence of an illegal market of pesticides banned in the European Union in the neighbouring African continent. In addition, the limited awareness of the population about the dangerousness of these compounds, for the environment, animals, or even people, make the situation very worrying in these islands. Stronger regulations, control of legal and illegal pesticide use, development of educational programs and legal action in poisoning incidents are needed to decrease the impact of pesticide misuse on wildlife and domestic animals.

  19. GIS methods applied to the degradation of monogenetic volcanic fields: A case study of the Holocene volcanism of Gran Canaria (Canary Islands, Spain)

    Science.gov (United States)

    Rodriguez-Gonzalez, A.; Fernandez-Turiel, J. L.; Perez-Torrado, F. J.; Aulinas, M.; Carracedo, J. C.; Gimeno, D.; Guillou, H.; Paris, R.

    2011-11-01

    Modeling of volcanic morphometry provides reliable measurements of parameters that assist in the determination of volcanic landform degradation. Variations of the original morphology enable the understanding of patterns affecting erosion and their development, facilitating the assessment of associated hazards. A total of 24 volcanic Holocene eruptions were identified in the island of Gran Canaria (Canary Islands, Spain). 87% of these eruptions occurred in a wet environment while the rest happened in a dry environment. 45% of Holocene eruptions are located along short barrancos (S-type, less than 10 km in length), 20% along large barrancos (L-type, 10-17 km in length) and 35% along extra-large barrancos (XL-type, more than 17 km in length). The erosional history of Holocene volcanic edifices is in the first stage of degradation, with a geomorphic signature characterized by a fresh, young cone with a sharp profile and a pristine lava flow. After intensive field work, a careful palaeo-geomorphological reconstruction of the 24 Holocene eruptions of Gran Canaria was conducted in order to obtain the Digital Terrain Models (DTMs) of the pre- and post-eruption terrains. From the difference between these DTMs, the degradation volume and the incision rate were obtained. The denudation of volcanic cones and lava flows is relatively independent both their geographical location and the climatic environment. However, local factors, such as pre-eruption topography and ravine type, have the greatest influence on the erosion of Holocene volcanic materials in Gran Canaria. Although age is a key factor to help understand the morphological evolution of monogenetic volcanic fields, the Gran Canaria Holocene volcanism presented in this paper demonstrates that local and regional factors may determine the lack of correlation between morphometric parameters and age. Consequently, the degree of transformation of the volcanic edifices evolves, in many cases, independently of their age.

  20. Eruptive response of oceanic islands to giant landslides: New insights from the geomorphologic evolution of the Teide-Pico Viejo volcanic complex (Tenerife, Canary)

    Science.gov (United States)

    Boulesteix, Thomas; Hildenbrand, Anthony; Gillot, Pierre-Yves; Soler, Vicente

    2012-02-01

    Large sector collapses are a major component of oceanic islands evolution. Here we show that voluminous events such as the Icod landslide on Tenerife (Canary Islands) cause dramatic changes on the magma feeding system and control the subsequent volcanic and geomorphologic evolution of the eruptive complex over a period of more than 150 kyr. Instantaneous unloading by the Icod landslide is marked by the development of a large phonolitic explosive eruption dated at 175 ± 3 ka and interpreted as reflecting the immediate emptying of a shallow pre-existing magma chamber. Geochronological, geomorphological and geochemical analyses, carried out on the post-landslide volcanic succession sampled in a 4.4 km-long underground water-recovery gallery, provide further evidence for an enhanced extrusion of primitive lavas starting in the 10 kyr time interval following the failure. Rapid construction (scar at high eruptive rates (up to 8 km 3 kyr -1) increased the lithostatic pressure which then favored the intermittent storage of basic magma under the edifice. This resulted in more episodic construction evidenced by a significant decrease in output rates and the increasing occurrence of lavas with intermediate composition from 117 ± 7 to 52 ± 7 ka. An apparent volcanic gap is observed between 52 ± 7 and 18 ± 1 ka, after which highly differentiated lavas have been dominantly erupted. We propose that part of the gap can be explained by the individualization of a shallow magma reservoir a few kilometers below the base of the Teide volcano. During recent periods, vertical and lateral extrusions of trachytic and phonolitic viscous bodies from this storage area contributed to increase the slope of the main edifice up to 35°, overall favoring its present-day instability.

  1. Xenopumice erupted on 15 October 2011 offshore of El Hierro (Canary Islands): a subvolcanic snapshot of magmatic, hydrothermal and pyrometamorphic processes

    Science.gov (United States)

    Del Moro, S.; Di Roberto, A.; Meletlidis, S.; Pompilio, M.; Bertagnini, A.; Agostini, S.; Ridolfi, F.; Renzulli, A.

    2015-06-01

    On 15 October 2011, a submarine eruption offshore of El Hierro Island gave rise to floating volcanic products, known as xenopumices, i.e., pumiceous xenoliths partly mingled and coated with the juvenile basanitic magma. Over the last few years, no consensus in the scientific community in explaining the origin of these products has been reached. In order to better understand the formation of xenopumice, we present a textural, mineralogical, and geochemical study of the possible magmatic, hydrothermal, and pyrometamorphic processes, which usually operate in the plumbing systems of active volcanoes. We carried out a comprehensive SEM investigation and Sr-Nd-Pb isotope analyses on some samples representative of three different xenopumice facies. All the data were compared with previous studies, new data for El Hierro extrusives and a literature dataset of Canary Islands igneous and sedimentary rocks. In the investigated xenopumices, we emphasize the presence of restitic magmatic phases as well as crystallization of minerals (mainly olivine + pyroxene + magnetite aggregates) as pseudomorphs after pre-existing mafic phenocrysts, providing evidence of pyrometamorphism induced by the high-T juvenile basanitic magma. In addition, we identify veins consisting of zircon + REE-oxides + mullite associated with Si-rich glass and hydrothermal quartz, which indicate the fundamental role played by hydrothermal fluid circulation in the xenopumice protolith. The petrological data agree with a pre-syneruptive formation of the xenopumice, when El Hierro basanite magma intruded hydrothermally altered trachyandesite to trachyte rocks and triggered local partial melting. Therefore, the El Hierro xenopumice represents a snapshot of the transient processes at the magma-wall rock interface, which normally occurs in the feeding system of active volcanoes.

  2. Conceptual model of Enchereda aquifer system (La Gomera, Canary Islands): contributions to other volcanic islands; Modelo conceptual del sistema acuifero de Enchereda (La Gomera, Islas Canarias): contribuciones a otras islas volcanicas

    Energy Technology Data Exchange (ETDEWEB)

    Izquierdo, T.; Herrera, R.; Marquez, A.

    2011-07-01

    Hydrogeological conceptual models are difficult to develop in volcanic islands due to scarce hydrogeologic information in the inner parts of the islands and the complex structure of volcanic materials. This complexity is increased by 1) destruction processes (for example, flank collapse) and 2) dike intrusion. Dikes can both channel groundwater flow parallel to their general trend or act as barriers impounding it. In this paper we evaluate the role of dikes and volcanoclastic deposits in Enchereda aquifer system (La Gomera, Canary Islands) regional flow and particularly, in its higher area. In this aquifer system three hydrostratigraphic units can be identified: the Lower Old Basalts, with low permeability; the Volcanic Breccia, impermeable; and the Upper Old Basalts, permeable. The breccia seems to act as the impermeable limit of the aquifer and the reconstruction of its geometry shows a coherent surface dipping about 13 degree centigrade towards the ESE what determines the regional flow in the aquifer. After dike mapping using aerial photograph and ortho photograph as well as mapping in the field and inside Ipalan water tunnel, four dike swarms have been identified. NW-SE dikes are the most frequent ones, and show a maximum density of more than 10 dikes/100 m, similar to rift zones in volcanic islands. These dikes are parallel to the regional flow and channel water flow whereas the N-S and NE-SW swarms impound groundwater rising the water table level forming a stepped surface as they are perpendicular to the regional flow. Lastly, W-E dikes seem to have little influence on the aquifer. Our results show the need of a re-evaluation of the role of dikes in the regional flow in other volcanic island aquifers in which their influence have been minimized as overlapping of different dike swarms can condition regional flow in the aquifer. (Author)

  3. Bone trace element pattern in an 18th century population sample of Tenerife (Canary Islands): comparison with a prehistoric one.

    Science.gov (United States)

    Arnay-de-la-Rosa, M; Gonzalez-Reimers, E; Velasco-Vazquez, J; Barros-Lopez, N; Galindo-Martin, L

    1998-10-01

    We have determined bone strontium (Sr), barium (Ba), calcium (Ca), and zinc (Zn) content in 24 samples belonging to adult individuals who died toward the end of the 18th century and were interred in a church's floor on the island of Tenerife, comparing the results with those obtained in 14 prehistoric samples of the same island and also with those of 7 modern controls. No differences were observed between the two ancient groups, which showed higher bone strontium and barium than the modern sample, and a slightly lower Ba/Sr ratio, thus pointing to consumption of marine sources.

  4. Stygofauna of the Canary Islands, 1. A new species of Pygocrangonyx, an amphipod genus with African affinities, from Fuerteventura

    NARCIS (Netherlands)

    Stock, Jan H.; Rondé-Broekhuizen, Brigitte L.M.

    1986-01-01

    A group of exclusively subterranean Amphipoda, the Metacrangonyx group, is distributed mainly in northwestern Africa, with peripheral isolates on the Balearic Islands and in the Sinai desert. The discovery of a new species of this group, belonging to Pygocrangonyx, a genus known from N.W. Morocco on

  5. Hydrogeochemical variations in groundwater periodically sampled at El Hierro (Canary Islands) and its relationships with the recent eruptive and unrest periods

    Science.gov (United States)

    Luengo-Oroz, Natividad; Torres, Pedro A.; Moure, David; D'Alessandro, Walter

    2014-05-01

    On 10 October 2011, a submarine volcanic eruption started 2 km south El Hierro Island (Canary Islands, Spain). Since July 2011 a dense multiparametric monitoring network was deployed all over the island by Instituto Geográfico Nacional (IGN). By the time the eruption started, almost 10000 earthquakes had been located and the deformation analyses showed a maximum deformation of more than 5 cm. After the end of the submarine eruption and up to now, several volcanic unrest processes have taken place in the island. The most relevant ones started on June 2012 and March 2013. Each of these periods has been evidenced by intense seismicity and ground deformation. In the framework of this volcanic surveillance program, the IGN team started to periodically sample five groundwater sampling sites. Some parameters have been determined directly in the field (temperature, pH, electric conductivity and alkalinity) and collected samples have been analysed in the laboratory for major (Na, K, NH4, Ca, Mg, SO4, Cl, HCO3, CO3, NO3, NO2, PO4, SiO2, Br, F) and trace elements (Be, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Ba, Hg, Tl, Pb, Th, U) contents. In a few cases samples for the chemical analysis of dissolved gases and for the determination of the isotopic composition of He have been collected at two of the sites. Significant increases in alkalinity have been recorded in all sampling sites correlated both to the eruptive period and also to the following unrest episodes. Such increases are probably related to the dissolution of magmatic CO2 exsolved from the rising magma batches. The magmatic contribution can be confirmed by the isotopic composition of dissolved He showing values in the range from 7.76 to 8.91 R/Ra. Since July 2011, only one important CO2 soil degassing anomaly has been detected. This anomalous flux (620 g/m2.d) was measured in a small area (0.36 km2) before the beginning of the submarine eruption and has not been detected again after the eruption onset

  6. Seroprevalence of canine heartworm disease (Dirofilaria immitis) on Tenerife Island: an epidemiological update.

    Science.gov (United States)

    Montoya, J A; Morales, M; Juste, M C; Bañares, A; Simon, F; Genchi, C

    2006-12-01

    Blood samples from 823 dogs were tested for circulating Dirofilaria immitis antigen during a 1-year period (May 2002 to May 2003) on Tenerife Island, Canary Islands, Spain. Seroprevalence of heartworm infection was 21%. Heartworm infection was similar in males and females and was more common in dogs aged >6 years. Distribution of infection in varying climatic zones was not statistically different.

  7. Subsidence and current strain patterns on Tenerife Island (Canary Archipelago, Spain) derived from continuous GNSS time series (2008-2015)

    Science.gov (United States)

    Sánchez-Alzola, A.; Martí, J.; García-Yeguas, A.; Gil, A. J.

    2016-11-01

    In this paper we present the current crustal deformation model of Tenerife Island derived from daily CGPS time series processing (2008-2015). Our results include the position time series, a global velocity estimation and the current crustal deformation on the island in terms of strain tensors. We detect a measurable subsidence of 1.5-2 mm/yr. in the proximities of the Cañadas-Teide-Pico Viejo (CTPV) complex. These values are higher in the central part of the complex and could be explained by a lateral spreading of the elastic lithosphere combined with the effect of the drastic descent of the water table in the island experienced during recent decades. The results show that the Anaga massif is stable in both its horizontal and vertical components. The strain tensor analysis shows a 70 nstrain/yr. E-W compression in the central complex, perpendicular to the 2004 sismo-volcanic area, and 50 nstrain/yr. SW-NE extension towards the Northeast ridge. The residual velocity and strain patterns coincide with a decline in volcanic activity since the 2004 unrest.

  8. The capturing of pollens in the atmosphere of La Laguna City, Tenerife, Canary Islands 1990-1995.

    Science.gov (United States)

    García Cobaleda, I; De la Torre Morin, F; García Robaina, J C; Hardisson de la Torre, A

    1997-01-01

    This paper forms part of a Doctorate Thesis, carried out in the Allergy and Immunology Department of the Nuestra Señora de la Candelaria Hospital, Tenerife, entitled "Epidemiology of Pollens on the Island of Tenerife. Allergy to Pollen". This paper deals with the capturing of pollen in the atmosphere of the city of La Laguna, Tenerife, during the period 1990-1995, and demonstrates that the Occidental Islands of the Canarian Archipelago are similar to a miniature continent with a special microclimate and a large amount of vegetation, where all classes of pollen can be found given the large variety of plants and trees including native species. High concentrations of more than 50 grains of pollen per m3 can be found in the air of the Occidental Islands, above all wild grasses, cultivated grasses, weeds, Artemisa vulgaris, Parietaria officinalis and Plantago lanceolata, and in a lowe proportion, Cupressaceae, Pinaceas, Mercurialis and Rumex. We have pollen concentrations very similar to other parts of the continent.

  9. Groundwater intensive exploitation and mining in Gran Canaria and Tenerife, Canary Islands, Spain: Hydrogeological, environmental, economic and social aspects.

    Science.gov (United States)

    Custodio, Emilio; Cabrera, María Del Carmen; Poncela, Roberto; Puga, Luis-Olavo; Skupien, Elzbieta; Del Villar, Alberto

    2016-07-01

    Intensive exploitation and continuous consumption of groundwater reserves (groundwater mining) have been real facts for decades in arid and semiarid areas. A summary of experience in the hydrogeological, economic, social and ethical consequences of groundwater intensive and mining exploitation in Gran Canaria and Tenerife Islands, in the Canarian Archipelago, is presented. Groundwater abstraction is less than recharge, but a significant outflow of groundwater to the sea cannot be avoided, especially in Tenerife, due to its younger volcanic coastal formations. Consequently, the intensive aquifer groundwater development by means of wells and water galleries (tunnels) has produced a groundwater reserve depletion of about 2km(3). Should current groundwater abstraction cease, the recovery time to close-to-natural conditions is from decades to one century, except in the mid and high elevations of Tenerife, where this recovery is not possible as aquifer formations will remain permanently drained by the numerous long water galleries. The socio-economic circumstances are complex due to a long standing history of water resources exploitation, successive social changes on each island, and well-established groundwater water trading, with complex relationships that affect water governance and the resulting ethical concerns. Gran Canaria and Tenerife are in an advanced groundwater exploitation stage and have a large water demand. They are good examples that allow drawing guidelines to evaluate groundwater development on other small high islands. After presenting the hydrogeological background, the socio-economic results are discussed to derive general knowledge to guide on water governance.

  10. Morphometry of Concepcion Bank: Evidence of Geological and Biological Processes on a Large Volcanic Seamount of the Canary Islands Seamount Province.

    Science.gov (United States)

    Rivera, Jesus; Canals, Miquel; Lastras, Galderic; Hermida, Nuria; Amblas, David; Arrese, Beatriz; Martín-Sosa, Pablo; Acosta, Juan

    2016-01-01

    Concepcion Bank is the largest seamount in the Canary Islands Seamount Province (CISP), an oceanic area off NW Africa including 16 main seamounts, the Canaries archipelago and the Selvagens subarchipelago. The Bank is located 90 km northeast of Lanzarote Island and has been identified as a candidate Marine Protected Area (MPA) to be included in the Natura 2000 network. A compilation of complementary datasets consisting of multibeam bathymetry, TOPAS seismic reflection profiles, side scan sonar sonographs, Remotely Operated Vehicle video records and seafloor samples allowed describing in detail and ground truthing the submarine landforms and bioconstructions exhibited by the bank. The Concepcion Bank presently rises up to 2,433 m above the adjacent seafloor and exhibits two main domains: an extensive summit plateau and steep flanks. The sub-round summit plateau is 50km by 45 km and ranges from 158 to 1,485 m depth. The steep flanks that bound it descend to depths ranging between 1,700 and 2,500 m and define a seamount base that is 66km by 53 km. This morphology is the result of constructive and erosive processes involving different time scales, volumes of material and rates of change. The volcanic emplacement phase probably lasted 25-30 million years and was likely responsible for most of the 2,730 km3 of material that presently form the seamount. Subsequently, marine abrasion and, possibly, subaerial erosion modulated by global sea level oscillations, levelled the formerly emerging seamount summit plateau, in particular its shallower (<400 m), flatter (<0.5°) eastern half. Subsidence associated to the crustal cooling that followed the emplacement phase further contributed the current depth range of the seamount. The deeper and steeper (2.3°) western half of Concepcion Bank may result from tectonic tilting normal to a NNE-SSW fracture line. This fracture may still be expressed on the seafloor surface at some scarps detected on the seamount's summit. Sediment waves

  11. Morphometry of Concepcion Bank: Evidence of Geological and Biological Processes on a Large Volcanic Seamount of the Canary Islands Seamount Province

    Science.gov (United States)

    Canals, Miquel; Lastras, Galderic; Hermida, Nuria; Amblas, David; Arrese, Beatriz; Martín-Sosa, Pablo; Acosta, Juan

    2016-01-01

    Concepcion Bank is the largest seamount in the Canary Islands Seamount Province (CISP), an oceanic area off NW Africa including 16 main seamounts, the Canaries archipelago and the Selvagens subarchipelago. The Bank is located 90 km northeast of Lanzarote Island and has been identified as a candidate Marine Protected Area (MPA) to be included in the Natura 2000 network. A compilation of complementary datasets consisting of multibeam bathymetry, TOPAS seismic reflection profiles, side scan sonar sonographs, Remotely Operated Vehicle video records and seafloor samples allowed describing in detail and ground truthing the submarine landforms and bioconstructions exhibited by the bank. The Concepcion Bank presently rises up to 2,433 m above the adjacent seafloor and exhibits two main domains: an extensive summit plateau and steep flanks. The sub-round summit plateau is 50km by 45 km and ranges from 158 to 1,485 m depth. The steep flanks that bound it descend to depths ranging between 1,700 and 2,500 m and define a seamount base that is 66km by 53 km. This morphology is the result of constructive and erosive processes involving different time scales, volumes of material and rates of change. The volcanic emplacement phase probably lasted 25–30 million years and was likely responsible for most of the 2,730 km3 of material that presently form the seamount. Subsequently, marine abrasion and, possibly, subaerial erosion modulated by global sea level oscillations, levelled the formerly emerging seamount summit plateau, in particular its shallower (<400 m), flatter (<0.5°) eastern half. Subsidence associated to the crustal cooling that followed the emplacement phase further contributed the current depth range of the seamount. The deeper and steeper (2.3°) western half of Concepcion Bank may result from tectonic tilting normal to a NNE-SSW fracture line. This fracture may still be expressed on the seafloor surface at some scarps detected on the seamount’s summit. Sediment

  12. A comparison of Thellier-type and multispecimen paleointensity determinations on Pleistocene and historical lava flows from Lanzarote (Canary Islands, Spain)

    Science.gov (United States)

    Calvo-Rathert, Manuel; Morales-Contreras, Juan; Carrancho, Ángel; Goguitchaichvili, Avto

    2016-09-01

    Sixteen Miocene, Pleistocene, and historic lava flows have been sampled in Lanzarote (Canary Islands) for paleointensity analysis with both the Coe and multispecimen methods. Besides obtaining new data, the main goal of the study was the comparison of paleointensity results determined with two different techniques. Characteristic Remanent Magnetization (ChRM) directions were obtained in 15 flows, and 12 were chosen for paleointensity determination. In Thellier-type experiments, a selection of reliable paleointensity determinations (43 of 78 studied samples) was performed using sets of criteria of different stringency, trying to relate the quality of results to the strictness of the chosen criteria. Uncorrected and fraction and domain-state corrected multispecimen paleointensity results were obtained in all flows. Results with the Coe method on historical flows either agree with the expected values or show moderately lower ones, but multispecimen determinations display a large deviation from the expected result in one case. No relation can be detected between correct or anomalous results and paleointensity determination quality or rock-magnetic properties. However, results on historical flows suggest that agreement between both methods could be a good indicator of correct determinations. Comparison of results obtained with both methods on seven Pleistocene flows yields an excellent agreement in four and disagreements in three cases. Pleistocene determinations were only accepted if either results from both methods agreed or a result was based on a sufficiently large number (n > 4) of individual Thellier-type determinations. In most Pleistocene flows, a VADM around 5 × 1022 Am2 was observed, although two flows displayed higher values around 9 × 1022 Am2.

  13. Fungicide resistance of Botrytis cinerea in tomato greenhouses in the Canary Islands and effectiveness of non-chemical treatments against gray mold.

    Science.gov (United States)

    Rodríguez, A; Acosta, A; Rodríguez, C

    2014-09-01

    Tomato greenhouses in the Canary Islands, Spain, were surveyed to estimate frequencies of resistance to benzimidazoles, dicarboximides, anilinopyrimidines and N-phenylcarbamates in Botrytis cinerea. Resistance to carbendazim, iprodione, pyrimethanil and diethofencarb was found in 74.2, 86.4, 28.8 and 31.8% of isolates, respectively. Benzimidazole- and anilinopyrimide-resistant isolates were highly resistant, showing EC50 values above 500 µg/ml carbendazim and a mean EC50 value of 28.42 µg/ml pyrimethanil, respectively. By contrast, a low level of resistance was observed among dicarboximide-resistant isolates (mean EC50 value of 1.81 µg/ml iprodione). Phenotypes with double resistance to carbendazim and iprodione, and triple resistance to carbendazim, iprodione and pyrimethanil were the most common, occurring in 36.4 and 28.8% of isolates. The surveyed greenhouses had never been treated with fenhexamid and Signum™ (pre-packed mixture of boscalid and pyraclostrobin), and baseline sensitivities of B. cinerea isolates to these fungicides were determined. The EC50 values were within the range of 0.009-0.795 µg/ml fenhexamid and of 0.014-0.48 µg/ml Signum. In addition, available formulations based on elicitors of plant defense response and biocontrol agents were evaluated against B. cinerea in tomato plants under semi-controlled greenhouse conditions, the yeast Candida sake CPA-1 being able to reduce gray mold significantly when it was applied on petiole wounds and the plants were inoculated 24 h later. Likewise, C. sake was effective against B. cinerea in harvested tomato fruits, yeast-treated tomatoes showed a 70.66 and 30.31% reduction in the diameters of decay lesions compared with controls after 10 days of storage at 20 and 9 °C, respectively.

  14. A complex Quaternary ignimbrite-forming phonolitic eruption: the Poris Member of the Diego Hernández Formation (Tenerife, Canary Islands)

    Science.gov (United States)

    Edgar, C. J.; Wolff, J. A.; Nichols, H. J.; Cas, R. A. F.; Martí, J.

    2002-11-01

    The Poris Member (0.28 Ma) of the Diego Hernández Formation (Tenerife, Canary Islands) is a widespread succession of plinian fall, surge and non-welded ignimbrite deposits. It was erupted from the northeastern sector of the multicyclic Las Cañadas Caldera, the summit caldera complex of the Las Cañadas Edifice. We present new stratigraphic data which allow the evolution of the eruption to be divided into six main stages: (1) an initial surge-producing phreatomagmatic phase. (2) Generation of a buoyant plinian column culminating in vent-wall collapse and temporary vent blockage. (3) A resumption of phreatomagmatic activity, producing accretionary lapilli-bearing ash surges and a phreatomagmatic ignimbrite. (4) Sustained column collapse, resulting in the progressive aggradation of a complex, compositionally layered ignimbrite sequence. (5) A late plinian phase marked by sharp chemical zonation. (6) Final vent destruction and the generation of multiple surges and pyroclastic flows. Volume calculations indicate a total erupted volume in the order of 13-14 km 3 (3-4 km 3 dense rock equivalent), which together with facies and lithic analysis implies that a small-scale caldera collapse occurred, contributing to the incremental enlargement of the Las Cañadas Caldera. The geochemistry and mingling inter-relationships of four magmatic endmembers, ranging from alkaline mafic to evolved phonolitic liquids, indicate that two magma chambers fed stages 4 and 5 of the eruption sequence. The eruption was triggered when mafic magma intruded the two-chamber system.

  15. Contribution of collagen stable isotope biogeochemistry to the paleobiology of extinct endemic vertebrates from Tenerife (Canary Islands, Spain).

    Science.gov (United States)

    Bocherens, H; Michaux, J; Billiou, D; Castanet, J; Garcìa-Talavera, F

    2003-09-01

    The paleodiet and paleoenvironmental context of two extinct species from Tenerife island, one giant rat Canariomys bravoi and one giant lizard Gallotia goliath, have been investigated using carbon and nitrogen isotopic compositions of fossil bone collagen. Preliminary to this study, a calibration of the isotopic variations of bone collagen from modern Rat Rattus rattus, Rabbit Oryctolagus cuniculus and Lizard Gallotia galotti relative to environmental conditions on Tenerife Islands has been attempted. No clear relationship could be found between collagen delta13C and delta15N values and aridity; the only relevant factors seem to be seashore proximity for rat, and the relative amount of C3 and CAM plants. It seems that anthropic activities have interfered with the expected relationships between collagen isotopic compositions and environmental conditions. Most fossil specimens yielded well preserved collagen. The isotopic composition of giant rat and giant lizard collagen suggest a purely C3 environment, possibly more humid than today on Tenerife. Large ranges of nitrogen isotopic compositions, especially within giant rats, may be due to local environmental conditions. Further work is needed in order to provide more valuable paleobiological information in order to better understand the role of environmental factors in the evolution and extinction of insular endemic species on Tenerife.

  16. Degradation of Cymodocea nodosa (Ucria) Ascherson meadow at Las Canteras Beach (Gran Canaria, Canary Islands, Atlantic Ocean)

    Institute of Scientific and Technical Information of China (English)

    Milena Polifrone; Miquel Rosell-Fieschi

    2014-01-01

    Objective: To monitor the distribution of Cymodocea nodosa (Ucria) Ascherson in Las Canteras Beach (Las Palmas de Gran Canaria, Spain), comparing the status in 2005 with the distribution observed in 1985 and 1995. Methods: Field observations by selfcontained underwater breathing apparatus diving records and cartographic report.Results:rocks, which sheltered it from the strong north-east winds and swells. Since 1985 a gradual reduction of its extent has been observed and more than 80% of the original canopy disappeared in twenty years time, mostly due to the anthropogenic impact and modification of the sedimentary dynamics of the beach.Conclusions:Conclusions: The degradation of this seagrass meadow determinates the loss of the only meadow in the north of the island of Gran Canaria and the absence of a management plan for its conservation.

  17. Spatial and temporal variations of diffuse CO_{2} degassing at the N-S volcanic rift-zone of Tenerife (Canary Islands, Spain) during 2002-2015 period

    Science.gov (United States)

    Alonso, Mar; Ingman, Dylan; Alexander, Scott; Barrancos, José; Rodríguez, Fátima; Melián, Gladys; Pérez, Nemesio M.

    2016-04-01

    Tenerife is the largest of the Canary Islands and, together with Gran Canaria Island, is the only one with a central volcanic complex that started to grow at about 3.5 Ma. Nowadays the central complex is formed by Las Cañadas caldera, a volcanic depression measuring 16×9 km that resulted from multiple vertical collapses and was partially filled by post-caldera volcanic products. Up to 297 mafic monogenetic cones have been recognized on Tenerife, and they represent the most common eruptive activity occurring on the island during the last 1 Ma (Dóniz et al., 2008). Most of the monogenetic cones are aligned following a triple junction-shaped rift system, as result of inflation produced by the concentration of emission vents and dykes in bands at 120o to one another as a result of minimum stress fracturing of the crust by a mantle upwelling. The main structural characteristic of the southern volcanic rift (N-S) of the island is an apparent absence of a distinct ridge, and a fan shaped distribution of monogenetic cones. Four main volcanic successions in the southern volcanic rift zone of Tenerife, temporally separated by longer periods (˜70 - 250 ka) without volcanic activity, have been identified (Kröchert and Buchner, 2008). Since there are currently no visible gas emissions at the N-S rift, diffuse degassing surveys have become an important geochemical tool for the surveillance of this volcanic system. We report here the last results of diffuse CO2 efflux survey at the N-S rift of Tenerife, performed using the accumulation chamber method in the summer period of 2015. The objectives of the surveys were: (i) to constrain the total CO2 output from the studied area and (ii) to evaluate occasional CO2 efflux surveys as a volcanic surveillance tool for the N-S rift of Tenerife. Soil CO2 efflux values ranged from non-detectable up to 31.7 g m-2 d-1. A spatial distribution map, constructed following the sequential Gaussian simulation (sGs) procedure, did not show an

  18. Crystal Zoning Constrains on the Processes and Time Scales Involved in Monogenetic Mafic Volcanism (Tenerife, Canary Islands)

    Science.gov (United States)

    Albert, H.; Costa Rodriguez, F.; Marti, J.

    2014-12-01

    Most of the historical eruptive activity in Tenerife has been relatively mafic and mildly-explosive monogenetic eruptions, and thus it seems that this activity is the most likely in the near future. Here we investigate the processes and time scales that lead to such eruptions with the aim to better interpret and plan for any possible unrest in the island. We focus on three historical eruptions: Siete Fuentes (December 31 1704-January 1705), Fasnia (January 5-January 13 1705) and Arafo (February 2-February 26 1705) issued from a 10 km long basaltic fissure eruption oriented N45E and covering an area of 10.4 km2. The erupted volume increases by 5-fold from the first to the last eruption. All magmas are tephritic, although the bulk-rock becomes more mafic with time due to accumulation of olivine with Cr-spinel inclusions, and clinopyroxene rather than to the appearance of a truly more primitive melt. Olivine core compositions of the three eruptions range between Fo79 and Fo87. Frequency histograms show three main populations: at Fo79-80, Fo80-82 and Fo84-87 displaying normal and reverse zoning. Thermodynamic calculations show that only cores with Fo80-82 are in equilibrium with the whole rock. Clinopyroxene phenocrysts can have large pools of matrix glass and show rims of different composition. Only the rims, with Mg#84-86, are in equilibrium with the whole-rock. Considering olivine cores and clinopyroxene rims in equilibrium we obtained a temperature range of 1150-1165°C, and MELTS calculations suggest pressures of 1 to 5 kbar. The variety of olivine core populations reflects mixing and mingling between three different magmas, and their proportions have changed with time from Siete Fuentes to Arafo. Most crystals have complex zoning profiles that record two events: (1) one of magma mixing/mingling at depth, (2) another of magma transport and ascent to the surface. Magma mixing at depth ranges from about 3 months to two years and is similar for the three eruptions

  19. Assessment of correlation between geophysical and hydrogeological parameters of volcanic deposits at Bandama Caldera (Gran Canaria, Canary Islands, Spain)

    Science.gov (United States)

    Casas, Albert; Himi, Mahjoub; Estévez, Esmeralda; Lovera, Raúl; Sendrós, Alexandre; Palacios-Díaz, M. Pino; Tapias, Josefina C.; Cabrera, M. Carmen

    2015-04-01

    The characterization of the preferential areas of water infiltration through the vadose zone is of paramount importance to assess the pollution vulnerability of the underlying aquifers. Nevertheless, geometry and the hydraulic conductivity of each geological unit which constitute the unsaturated zone are difficult to study from traditional techniques (samples from trenches) and normally do not go beyond a meter depth from of the surface. On the other hand, boreholes are expensive and provide only local information not always representative of the whole unsaturated zone. For this reason, geophysical techniques and among them the electrical resistivity tomography method can be applicable in volcanic areas, where basaltic rocks, pyroclastic and volcanic ash-fall deposits have a wide range of values. In order to characterize the subsurface geology below the golf course of Bandama (Gran Canaria Island), irrigated with reclaimed wastewater, a detailed electrical resistivity tomography survey has been carried out. This technique has allowed to define the geometry of the existing geological formations by their high electrical resistivity contrast. Subsequently, in representative outcrops the value of resistivity of each of these lithologies has been measured and simultaneously undisturbed samples have been taken measuring the hydraulic conductivity in the laboratory. Finally a statistical correlation between both variables has been established for evaluating the vulnerability to groundwater pollution at different zones of the golf course.

  20. Different deformation patterns using GPS in the volcanic process of El Hierro (Canary Island) 2011-2013

    Science.gov (United States)

    García-Cañada, Laura; José García-Arias, María; Pereda de Pablo, Jorge; Lamolda, Héctor; López, Carmen

    2014-05-01

    Ground deformation is one of the most important parameter in volcano monitoring. The detected deformations in volcanic areas can be precursors of a volcanic activity and contribute with useful information to study the evolution of an unrest, eruption or any volcanic process. GPS is the most common technique used to measure volcano deformations. It can be used to detect slow displacement rates or much larger and faster deformations associated with any volcanic process. In volcanoes the deformation is expected to be a mixed of nature; during periods of quiescence it will be slow or not present, while increased activity slow displacement rates can be detected or much larger and faster deformations can be measure due to magma intrusion, for example in the hours to days prior a eruption beginning. In response to the anomalous seismicity detected at El Hierro in July 2011, the Instituto Geográfico Nacional (IGN) improved its volcano monitoring network in the island with continuous GPS that had been used to measure the ground deformation associated with the precursory unrest since summer 2011, submarine eruption (October 2011-March 2012) and the following unrest periods (2012-2013). The continuous GPS time series, together with other techniques, had been used to evaluate the activity and to detect changes in the process. We investigate changes in the direction and module of the deformation obtained by GPS and they show different patterns in every unrest period, very close to the seismicity locations and migrations.

  1. Behaviour of a small sedimentary volcanic aquifer receiving irrigation return flows: La Aldea, Gran Canaria, Canary Islands (Spain)

    Science.gov (United States)

    Cruz-Fuentes, T.; Heredia, J.; Cabrera, M. C.; Custodio, E.

    2014-06-01

    In many arid and semi-arid areas, intensive cultivation is practiced despite water commonly being a limiting factor. Often, irrigation water is from local aquifers or imported from out-of-area aquifers and surface reservoirs. Irrigation return flows become a significant local recharge source, but they may deteriorate aquifer water quality. La Aldea valley, located in the western sector of Gran Canaria Island (Atlantic Ocean), is a coastal, half-closed depression in altered, low-permeability volcanics with alluvium in the gullies and scree deposits over a large part of the area. This area is intensively cultivated. Irrigation water comes from reservoirs upstream and is supplemented (average 30 %) by local groundwater; supplementation goes up to 70 % in dry years, in which groundwater reserves are used up to exhaustion if the dry period persists. Thus, La Aldea aquifer is key to the water-supply system, whose recharge is mostly from return irrigation flows and the scarce local rainfall recharge on the scree formations, conveyed to the gully deposits. To quantify the hydrogeological conceptual model and check data coherence, a simplified numerical model has been constructed, which can be used as a tool to help in water management.

  2. Are closed landfills free of CH_{4} emissions? A case study of Arico's landfill, Tenerife, Canary Islands

    Science.gov (United States)

    Barrancos, José; Cook, Jenny; Phillips, Victoria; Asensio-Ramos, María; Melián, Gladys; Hernández, Pedro A.; Pérez, Nemesio M.

    2016-04-01

    Landfills are authentic chemical and biological reactors that introduce in the environment a wide amount of gas pollutants (CO2, CH4, volatile organic compounds, etc.) and leachates. Even after years of being closed, a significant amount of landfill gas could be released to the atmosphere through the surface in a diffuse form, also known as non-controlled emission. The study of the spatial-temporal distribution of diffuse emissions provides information of how a landfill degassing takes place. The main objective of this study was to estimate the diffuse uncontrolled emission of CH4 into the atmosphere from the closed Arico's landfill (0.3 km2) in Tenerife Island, Spain. To do so, a non-controlled biogenic gas emission survey of nearly 450 sampling sites was carried out during August 2015. Surface gas sampling and surface landfill CO2 efflux measurements were carried out at each sampling site by means of a portable non-dispersive infrared spectrophotometer (NDIR) model LICOR Li800 following the accumulation chamber method. Landfill gases, CO2 and CH4, were analyzed using a double channel VARIAN 4900 micro-GC. The CH4 efflux was computed combining CO2 efflux and CH4/CO2 ratio in the landfill's surface gas. To quantify the total CH4 emission, CH4 efflux contour map was constructed using sequential Gaussian simulation (sGs) as interpolation method. The total diffuse CH4 emission was estimated in 2.2 t d-1, with CH4 efflux values ranging from 0-922 mg m-2 d-1. This type of studies provides knowledge of how a landfill degasses and serves to public and private entities to establish effective systems for extraction of biogas. This aims not only to achieve higher levels of controlled gas release from landfills resulting in a higher level of energy production but also will contribute to minimize air pollution caused by them.

  3. Diffuse volcanic degassing and thermal energy release 2015 surveys from the summit cone of Teide volcano, Tenerife (Canary Islands, Spain)

    Science.gov (United States)

    Melián, Gladys; Asensio-Ramos, María; Padilla, Germán; Alonso, Mar; Halliwell, Simon; Sharp, Emerson; Butters, Damaris; Ingman, Dylan; Alexander, Scott; Cook, Jenny; Pérez, Nemesio M.

    2016-04-01

    The summit cone of Teide volcano (Spain) is characterized by the presence of a weak fumarolic system, steamy ground, and high rates of diffuse CO2 degassing all around this area. The temperature of the fumaroles (83° C) corresponds to the boiling point of water at discharge conditions. Water is the major component of these fumarolic emissions, followed by CO2, N2, H2, H2S, HCl, Ar, CH4, He and CO, a composition typical of hydrothermal fluids. Previous diffuse CO2 surveys have shown to be an important tool to detect early warnings of possible impending volcanic unrests at Tenerife Island (Melián et al., 2012; Pérez et al., 2013). In July 2015, a soil and fumarole gas survey was undertaken in order to estimate the diffuse volcanic degassing and thermal energy release from the summit cone of Teide volcano. A diffuse CO2 emission survey was performed selecting 170 observation sites according to the accumulation chamber method. Soil CO2 efflux values range from non-detectable (˜0.5 g m-2d-1) up to 10,672 g m-2d-1, with an average value of 601 g m-2d-1. Spatial distribution maps were constructed following the sequential Gaussian simulation (sGs) procedure. Measurement of soil CO2 efflux allowed an estimation of 162 ± 14 t d-1 of deep seated derived CO2. To calculate the steam discharge associated with this volcanic/hydrothermal CO2 output, we used the average H2O/CO2 mass ratio equal to 1.19 (range, 0.44-3.42) as a representative value of the H2O/CO2 mass ratios for Teide fumaroles. The resulting estimate of the steam flow associated with the gas flux is equal to 193 t d-1. The condensation of this steam results in a thermal energy release of 5.0×1011J d-1 for Teide volcano or a total heat flow of 6 MWt. The diffuse gas emissions and thermal energy released from the summit of Teide volcano are comparable to those observed at other volcanoes. Sustained surveillance using these methods will be valuable for monitoring the activity of Teide volcano.

  4. Chronology and volcanology of the 1949 multi-vent rift-zone eruption on La Palma (Canary Islands)

    Science.gov (United States)

    Klügel, A.; Schmincke, H.-U.; White, J. D. L.; Hoernle, K. A.

    1999-12-01

    The compositionally zoned San Juan eruption on La Palma emanated from three eruptive centers located along a north-south-trending rift zone in the south of the island. Seismic precursors began weakly in 1936 and became strong in March 1949, with their foci progressing from the north of the rift zone towards its south. This suggests that magma ascended beneath the old Taburiente shield volcano and moved southward along the rift. The eruption began on June 24, 1949, with phreatomagmatic activity at Duraznero crater on the ridgetop (ca. 1880 m above sea level), where five vents erupted tephritic lava along a 400-m-long fissure. On June 8, the Duraznero vents shut down abruptly, and the activity shifted to an off-rift fissure at Llano del Banco, located at ca. 550 m lower elevation and 3 km to the northwest. This eruptive center issued initially tephritic aa and later basanitic pahoehoe lava at high rates, producing a lava flow that entered the sea. Two days after basanite began to erupt at Llano del Banco, Hoyo Negro crater (ca. 1880 m asl), located 700 m north of Duraznero along the rift, opened on July 12 and produced ash and bombs of basanitic to phonotephritic composition in violent phreatomagmatic explosions ( White and Schmincke, 1999). Llano del Banco and Hoyo Negro were simultaneously active for 11 days and showed a co-variance of their eruption rates indicating a shallow hydraulic connection. On July 30, after 3 days of quiescence at all vents, Duraznero and Hoyo Negro became active again during a final eruptive phase. Duraznero issued basanitic lava at high rates for 12 h and produced a lava flow that descended towards the east coast. The lava contains ca. 1 vol.% crustal and mantle xenoliths consisting of 40% tholeiitic gabbros from the oceanic crust, 35% alkaline gabbros, and 20% ultramafic cumulates. The occurrence of xenoliths almost exclusively in the final lava is consistent with their origin by wall-rock collapse at depth near the end of the eruption

  5. Valoración nutricional de trabajadores sanitarios expuestos a turnicidad en Canarias Nutritional evaluation of health shift workers from the Canary Islands

    Directory of Open Access Journals (Sweden)

    M. Jesús Fernández Rodríguez

    2004-10-01

    Full Text Available Objetivo: El trabajo a turnos induce hábitos de vida anómalos, lo cual se asocia al aumento de la morbilidad en los trabajadores. En este estudio se valoró el estado nutricional, los hábitos alimentarios y la actividad física de trabajadores hospitalarios sometidos a turnos. Ámbito: La población de estudio estuvo compuesta por 207 trabajadores con turno fijo de mañana y 210 con turno rotatorio (mañana, tarde y noche seleccionados aleatoriamente entre 2.100 trabajadores. Intervenciones: La ingesta dietética se determinó mediante cuestionario de frecuencia de consumo de alimentos autoadministrado. También se determinaron índice de masa corporal, parámetros lipídicos (colesterol total, colesterol HDL, colesterol LDL y triglicéridos, actividad física, edad y sexo. Resultados: Los trabajadores sometidos a turnicidad mostraron un mayor consumo de ternera, huevos, zumos y pastas. No se encontraron diferencias significativas en cuanto a niveles lipídicos, estado ponderal ni de actividad física entre los trabajos sometidos y no a turnicidad y no. El 62% de los hombres y el 37,2% de las mujeres mostraron sobrecarga ponderal (obesidad y sobrepeso. El 46% de los individuos de la muestra presentaron sedentarismo. Conclusiones: La turnicidad en los trabajadores hospitalarios influye sólo parcialmente en los hábitos alimentarios de dicho colectivo.Objective: Shift workers are known to have increased morbidity associated to wrong habits. In this study we have evaluated the nutritional status, food habits and physical activity in health shift workers. Subjects: 207 permanent morning-shift workers and 210 shift workers (3-shift system were randomized selected from the 2,100 workers of the North Area of the Canary Island Sanitary Health System. Methods: Dietary intake was assessed by a self-registered food frequency questionnaire. We also assessed Body Mass Index, blood lipid levels (total cholesterol, HDL cholesterol, LDL cholesterol and

  6. Insights into the 2011-2012 submarine eruption off the coast of El Hierro (Canary Islands, Spain) from statistical analyses of earthquake activity

    Science.gov (United States)

    Ibáñez, J. M.; De Angelis, S.; Díaz-Moreno, A.; Hernández, P.; Alguacil, G.; Posadas, A.; Pérez, N.

    2012-08-01

    The purpose of this work is to gain insights into the 2011-2012 eruption of El Hierro (Canary Islands) by mapping the evolution of the seismic b-value. The El Hierro seismic sequence offers a rather unique opportunity to investigate the process of reawakening of an oceanic intraplate volcano after a long period of repose. The 2011-2012 eruption is a submarine volcanic event that took place about 2 km off of the southern coast of El Hierro. The eruption was accompanied by an intense seismic swarm and surface manifestations of activity. The earthquake catalogue during the period of unrest includes over 12 000 events, the largest with magnitude 4.6. The seismic sequence can be grouped into three distinct phases, which correspond to well-separated spatial clusters and distinct earthquake regimes. The estimated b-value is of 1.18 ± 0.03, and a magnitude of completeness of 1.3, for the entire catalogue. B is very close to 1.0, which indicates completeness of the earthquake catalogue with only minor departures from the linearity of Gutenberg-Richter frequency-magnitude distribution. The most straightforward interpretation of this result is that the seismic swarm reached its final stages, and no additional large magnitude events should be anticipated, similarly to what one would expect for non-volcanic earthquake sequences. The results, dividing the activity in different phases, illustrate remarkable differences in the estimate of b-value during the early and late stages of the eruption. The early pre-eruptive activity was characterized by a b-value of 2.25. In contrast, the b-value was 1.25 during the eruptive phase. Based on our analyses, and the results of other studies, we propose a scenario that may account for the observations reported in this work. We infer that the earthquakes that occurred in the first phase reflect magma migration from the upper mantle to crustal depths. The area where magma initially intruded into the crust, because of its transitional nature

  7. The submarine eruption of La Restinga (El Hierro, Canary Islands): October 2011-March 2012; La erupcion submarina de La Restinga en la isla de El Hierro, Canarias: Octubre 2011-Marzo 2012

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Torrado, F. J.; Carracedo, J. C.; Rodriguez-Gonzalez, A.; Soler, V.; Troll, V. R.; Wiesmaier, S.

    2012-11-01

    The first signs of renewed volcanic activity at El Hierro began in July 2011 with the occurrence of abundant, low-magnitude earthquakes. The increasing seismicity culminated on October 10, 2011, with the onset of a submarine eruption about 2 km offshore from La Restinga, the southernmost village on El Hierro. The analysis of seismic and deformation records prior to, and throughout, the eruption allowed the reconstruction of its main phases: 1) ascent of magma and migration of hypo centres from beneath the northern coast (El Golfo) towards the south rift zone, close to La Restinga, probably marking the hydraulic fracturing and the opening of the eruptive conduit; and 2) onset and development of a volcanic eruption indicated by sustained and prolonged harmonic tremor whose intensity varied with time. The features monitored during the eruption include location, depth and morphological evolution of the eruptive source and emission of floating volcanic bombs. These bombs initially showed white, vesiculated cores (originated by partial melting of underlying pre-volcanic sediments upon which the island of El Hierro was constructed) and black basanite rims, and later exclusively hollow basanitic lava balloons. The eruptive products have been matched with a fissural submarine eruption without ever having attained surtseyan explosiveness. The eruption has been active for about five months and ended in March 2012, thus becoming the second longest reported historical eruption in the Canary Islands after the Timanfaya eruption in Lanzarote (1730-1736). This eruption provided the first opportunity in 40 years to manage a volcanic crisis in the Canary Islands and to assess the interpretations and decisions taken, thereby gaining experience for improved management of future volcanic activity. Seismicity and deformation during the eruption were recorded and analysed by the Instituto Geografico Nacional (IGN). Unfortunately, a lack of systematic sampling of erupted pyroclasts and

  8. How to define nativeness in vagile organisms: lessons from the cosmopolitan moss Bryum argenteum on the island of Tenerife (Canary Islands).

    Science.gov (United States)

    Pisa, S; Vanderpoorten, A; Patiño, J; Werner, O; González-Mancebo, J M; Ros, R M

    2015-09-01

    The distinction between native and introduced biotas presents unique challenges that culminate in organisms with high long-distance dispersal capacities in a rapidly changing world. Bryophytes, in particular, exhibit large distribution ranges, and some species can truly be qualified as cosmopolitan. Cosmopolitan species, however, typically occur in disturbed environments, raising the question of their nativeness throughout their range. Here, we employ genetic data to address the question of the origin of the cosmopolitan, weedy moss Bryum argenteum on the island of Tenerife. The genetic diversity of B. argenteum on Tenerife was comparable to that found in continental areas due to recurrent colonisation events, erasing any signature of a bottleneck that would be expected in the case of a recent colonisation event. The molecular dating analyses indicated that the first colonisation of the island took place more than 100,000 years ago, i.e. well before the first human settlements. Furthermore, the significant signal for isolation-by-distance found in B. argenteum within Tenerife points to the substantial role of genetic drift in establishing the observed patterns of genetic variation. Together, the results support the hypothesis that B. argenteum is native on Tenerife; although the existence of haplotypes shared between Tenerife and continental areas suggests that more recent, potentially man-mediated introduction also took place. While defining nativeness in organisms that are not deliberately introduced, and wherein the fossil record is extremely scarce, is an exceedingly challenging task, our results suggest that population genetic analyses can represent a useful tool to help distinguish native from alien populations.

  9. Towards the standardisation of the neuroblastoma (neuro-2a) cell-based assay for ciguatoxin-like toxicity detection in fish: application to fish caught in the Canary Islands.

    Science.gov (United States)

    Caillaud, A; Eixarch, H; de la Iglesia, P; Rodriguez, M; Dominguez, L; Andree, K B; Diogène, J

    2012-01-01

    The ouabain/veratridine-dependent neuroblastoma (neuro-2a) cell-based assay (CBA) was applied for the determination of the presence of ciguatoxin (CTX)-like compounds in ciguatera-suspected fish samples caught in the Canary Islands. In order to avoid matrix interferences the maximal concentration of wet weight fish tissue exposed to the neuro-2a cells was set at 20 mg tissue equivalent (TE) ml(-1) according to the sample preparation procedure applied. In the present study, the limit of quantification (LOQ) of CTX1B equivalents in fish extract was set at the limit of detection (LOD), being defined as the concentration of CTX1B equivalents inhibiting 20% cell viability (IC(20)). The LOQ was estimated as 0.0096 ng CTX1B eq.g TE(-1) with 23-31% variability between experiments. These values were deemed sufficient even though quantification given at the IC(50) (the concentration of CTX1B equivalents inhibiting 50% cell viability) is more accurate with a variability of 17-19% between experiments. Among the 13 fish samples tested, four fish samples were toxic to the neuro-2a cells with estimations of the content in CTX1B g(-1) of TE ranging from 0.058 (± 0.012) to 6.23 (± 0.713) ng CTX1B eq.g TE(-1). The high sensitivity and specificity of the assay for CTX1B confirmed its suitability as a screening tool of CTX-like compounds in fish extracts at levels that may cause ciguatera fish poisoning. Species identification of fish samples by DNA sequence analysis was conducted in order to confirm tentatively the identity of ciguatera risk species and it revealed some evidence of inadvertent misidentification. Results presented in this study are a contribution to the standardisation of the neuro-2a CBA and to the risk analysis for ciguatera in the Canary Islands.

  10. Lifetime of an ocean island volcano feeder zone: constraints from U-Pb dating on coexisting zircon and baddeleyite, and 40/39Ar age determinations, Fuerteventura, Canary Islands

    Science.gov (United States)

    Allibon, James; Ovtcharova, Maria; Bussy, Francois; Cosca, Michael; Schaltegger, Urs; Bussien, Denise; Lewin, Eric

    2011-01-01

    High-precision isotope dilution - thermal ionization mass spectrometry (ID-TIMS) U-Pb zircon and baddeleyite ages from the PX1 vertically layered mafic intrusion Fuerteventura, Canary Islands, indicate initiation of magma crystallization at 22.10 ± 0.07 Ma. The magmatic activity lasted a minimum of 0.52 Ma. 40Ar/39Ar amphibole dating yielded ages from 21.9 ± 0.6 to 21.8 ± 0.3, identical within errors to the U-Pb ages, despite the expected 1% theoretical bias between 40Ar/39Ar and U-Pb dates. This overlap could result from (i) rapid cooling of the intrusion (i.e., less than the 0.3 to 0.6 Ma 40Ar/39Ar age uncertainties) from closure temperatures (Tc) of zircon (699-988 °C) to amphibole (500-600 °C); (ii) lead loss affecting the youngest zircons; or (iii) excess argon shifting the plateau ages towards older values. The combination of the 40Ar/39Ar and U/Pb datasets implies that the maximum amount of time PX1 intrusion took to cool below amphibole Tc is 0.8 Ma, suggesting PX1 lifetime of 520,000 to 800,000 Ma. Age disparities among coexisting baddeleyite and zircon (22.10 ± 0.07/0.08/0.15 Ma and 21.58 ± 0.15/0.16/0.31 Ma) in a gabbro sample from the pluton margin suggest complex genetic relationships between phases. Baddeleyite is found preserved in plagioclase cores and crystallized early from low silica activity magma. Zircon crystallized later in a higher silica activity environment and is found in secondary scapolite and is found close to calcite veins, in secondary scapolite that recrystallised from plagioclase. close to calcite veins. Oxygen isotope δ18O values of altered plagioclase are high (+7.7), indicating interaction with fluids derived from host-rock carbonatites. The coexistence of baddeleyite and zircon is ascribed to interaction of the PX1 gabbro with CO2-rich carbonatite-derived fluids released during contact metamorphism.

  11. Troop Takeover and Reproductive Success of Wild Male Japanese Macaques on Yakushima Island (Macaca fuscata yakui

    Directory of Open Access Journals (Sweden)

    Sachiko Hayakawa

    2011-01-01

    Full Text Available Troop takeover is common in one-male primate groups, but there are few reports in multimale groups. Japanese macaques (Macaca fuscata form multimale groups and males commonly join troops at the bottom rank. On Yakushima island, however, where group size is relatively small, entrance into groups at the alpha position is also observed. This paper reports on the general features of troop takeover, on the predictors of takeover events, and on the reproductive success of takeover males. Troop takeovers occurred only in the mating season; nontroop males (NTMs did not cooperate with each other; former alpha males were rarely expelled from the troop; new alpha males did not commit infanticide; new alpha male tenure in the group was usually less than two years. Logistic regression analysis showed that the number of NTMs associating with a troop predicted the occurrence of troop takeover. Paternity discrimination revealed that 33.3% (3/9 of takeover males succeeded in siring offspring. Contrary to this low success rate, binary logistic regression analysis revealed that the takeover males can expect higher reproductive success compared to troop males. Entering a troop and out-competing the alpha male is one of many available strategies to attain reproductive success in male Japanese macaques.

  12. Transferring and implementing the general dynamic model of oceanic island biogeography at the scale of island fragments: the role of geological age and topography in plant diversification in the Canaries

    DEFF Research Database (Denmark)

    Otto, Rüdiger; Whittaker, Robert J.; von Gaisberg, Markus;

    2016-01-01

    Aim The general dynamic model (GDM) of oceanic island biogeography integrates rates of immigration, speciation and extinction in relation to a humped trajectory of island area and topographic complexity through time, based on a simplified island ontogeny. In practice, many islands have more compl...

  13. Estimated exposure to EU regulated mycotoxins and risk characterization of aflatoxin-induced hepatic toxicity through the consumption of the toasted cereal flour called "gofio", a traditional food of the Canary Islands (Spain).

    Science.gov (United States)

    Luzardo, Octavio P; Bernal-Suárez, María Del Mar; Camacho, María; Henríquez-Hernández, Luis Alberto; Boada, Luis D; Rial-Berriel, Cristian; Almeida-González, Maira; Zumbado, Manuel; Díaz-Díaz, Ricardo

    2016-07-01

    "Gofio" is a type of flour made from toasted grain, which is part of the staple food in the Canary Islands, Spain, in which the occurrence of Aflatoxins B1, B2, G1 and G2 (AFB1, AFB2, AFG1, AFG2), Fumonisins B1 and B2 (FB1 and FB2) Ochratoxin A (OTA), Deoxynivalenol (DNV) and Zearalenone (ZEA) was evaluated. 83% of the samples were contaminated with at least one mycotoxin and 69.2% of the analyzed samples showed co-occurrence of mycotoxins (range 2 to 8). All the concentrations were well below the established limits (maximum values of AFs=0.42 μg/kg; FBs=178.3 μg/kg; OTA=0.3 μg/kg; DON=92.5 μg/kg; and ZEA=9.9 μg/kg). The daily dietary exposure to total AFs was estimated to be 7.1% of the TDI. This value was almost double in children, and considering the upper-bound approach could reach 35% of the TDI. For the rest of mycotoxins, the consumers would be exposed to less than 2% of their TDIs. The risk characterization indicates that there is a potential risk in developing aflatoxin induced liver cancer due to gofio consumption in the subpopulation which is simultaneously exposed to other hepatocarcinogens, such as the hepatitis B virus.

  14. Deformation in volcanic areas: a numerical approach for their prediction in Teide volcano (Tenerife, Canary Islands); Deformaciones en areas volcanicas: una aproximacin numerica para su prediccion en el volcan Teide (Tenerife, Islas Canarias)

    Energy Technology Data Exchange (ETDEWEB)

    Charco, M.; Galan del Sastre, P.

    2011-07-01

    Active volcanic areas study comprises both, observation of physical changes in the natural media and the interpretation of such changes. Nowadays, the application of spatial geodetic techniques, such as GPS (Global Positioning System) or InSAR (Interferometry with Synthetic Aperture Radar), for deformation understanding in volcanic areas, revolutionizes our view of this geodetic signals. Deformation of the Earth's surface reflects tectonic, magmatic and hydrothermal processes at depth. In this way, the prediction of volcanic deformation through physical modelling provides a link between the observation and depth interior processes that could be crucial for volcanic hazards assessment. In this work, we develop a numerical model for elastic deformation study. The Finite Element Method (FEM) is used for the implementation of the numerical model. FEM allows to take into account different morphology, structural characteristics and the mechanical heterogeneities of the medium. Numerical simulations of deformation in Tenerife (Canary Islands) taking into account different medium hypothesis allow us to conclude that the accuracy of the predictions depends on how well the natural system is described. (Author) 22 refs.

  15. Foundations and anchors for a 250 m span arch bridge in la Palma Island (Canaries); Cimentaciones y anclajes para la construccion del Arco de los tilos, de 250 m. de luz, en la isla de la Palma (Canarias)

    Energy Technology Data Exchange (ETDEWEB)

    Simic Sureda, D.

    2008-07-01

    There are no simple procedures to estimate the bearing capacity of direct foundations on rock due to its anisotropy, as the criteria have to take into account different features concerning the rock discontinuities (spacing, orientation, opening, persistence,...) as well as other aspects concerning the rock matrix, particularly its strength when it is low. In this sense, the volcanic formations of the Canary Island pose important difficulties to the designer of foundations given their highly anisotropic fabric, which is the result of a complex origin where the basalt sheets alternate with fragmentary material of pyroclastic nature. This volcanic building is frequently intersected by old vents, in the guise of pipes plugged with broken fragments of low compacity. In a valley of highly dissected steep slopes of such geology an arch bridge has been designed and built with a span between supports of 250 m. This paper describes the analysis that was carried out to take into account the particularities of rock anisotropy and the foundations geometry in very steep slopes. The construction problems are also addressed in the paper, describing the grouting treatment that was needed in one of the supports due to the presence of an old vent. (Author) 7 refs.

  16. Coeval giant landslides in the Canary Islands: Implications for global, regional and local triggers of giant flank collapses on oceanic volcanoes

    Science.gov (United States)

    Boulesteix, Thomas; Hildenbrand, Anthony; Soler, Vicente; Quidelleur, Xavier; Gillot, Pierre-Yves

    2013-05-01

    Giant landslides are an important part of the evolution of most intra-plate volcanic islands. They often proceed in catastrophic events, likely to generate voluminous debris avalanches and eventually trigger destructive tsunamis. Although knowledge of the timing of their recurrence is a key factor regarding the hazard assessment in coastal environments, only a few of them have been well dated. In this contribution, we focus on the La Orotava event on Tenerife, which we date with the unspiked K-Ar technique, between 534 and 523 ka. Such narrow temporal interval is compatible, within uncertainties, with the age of the Cumbre Nueva collapse on the neighboring island of La Palma. We thus examine here the possible common triggering mechanisms at the global, regional and local scales. Both events occurred shortly after the climax of the oxygen isotopic stage 14, during the rapid transition towards the interglacial stage 13, reinforcing the hypothesis of a control from global paleoclimatic changes on the destabilization of oceanic islands. Intense volcanic pulses at the regional scale also lead to the synchronous overgrowth of several volcanic islands in the archipelago, but coeval destabilization on Tenerife and La Palma appears significantly controlled by the intrinsic morphology of the edifices, with contrasted instability thresholds for shield volcanoes and volcanic ridges respectively. Finally, we propose that the two events may be genetically linked. Dynamic transfer of voluminous debris avalanches during a giant landslide episode can induce isostatic readjustments, generate significant ground acceleration and finally produce a large tsunami, three processes which can concur to trigger large scale flank collapse on a neighboring mature unstable volcanic island.

  17. Impact of environmental factors on the spectral characteristics of lava surfaces:field spectrometry of basaltic lava flows on Tenerife, Canary Islands, Spain

    OpenAIRE

    Long Li; Carmen Solana; Frank Canters; Jonathan C.-W. Chan; Matthieu Kervyn

    2015-01-01

    We report on spectral reflectance measurements of basaltic lava flows on Tenerife Island, Spain. Lava flow surfaces of different ages, surface roughness and elevations were systematically measured using a field spectroradiometer operating in the range of 350–2500 nm. Surface roughness, oxidation and lichen coverage were documented at each measured site. Spectral properties vary with age and morphology of lava. Pre-historical lavas with no biological coverage show a prominent increase in spect...

  18. Power System Stability of a Small Sized Isolated Network Supplied by a Combined Wind-Pumped Storage Generation System: A Case Study in the Canary Islands

    Directory of Open Access Journals (Sweden)

    Carlos A. Platero

    2012-07-01

    Full Text Available Massive integration of renewable energy sources in electrical power systems of remote islands is a subject of current interest. The increasing cost of fossil fuels, transport costs to isolated sites and environmental concerns constitute a serious drawback to the use of conventional fossil fuel plants. In a weak electrical grid, as it is typical on an island, if a large amount of conventional generation is substituted by renewable energy sources, power system safety and stability can be compromised, in the case of large grid disturbances. In this work, a model for transient stability analysis of an isolated electrical grid exclusively fed from a combination of renewable energy sources has been studied. This new generation model will be installed in El Hierro Island, in Spain. Additionally, an operation strategy to coordinate the generation units (wind, hydro is also established. Attention is given to the assessment of inertial energy and reactive current to guarantee power system stability against large disturbances. The effectiveness of the proposed strategy is shown by means of simulation results.

  19. Los costes socioeconómicos de las enfermedades cardiovasculares y del cáncer en las Islas Canarias en 1998 Socioeconomic costs of cardiovascular disease and cancer in the Canary Islands [Spain] in 1998

    Directory of Open Access Journals (Sweden)

    J. López-Bastida

    2003-06-01

    Full Text Available Objetivo: Evaluar el impacto económico, en términos de costes directos e indirectos, de las enfermedades cardiovasculares y del cáncer, en Canarias, durante el año 1998. Métodos: El enfoque que se ha utilizado es el método del coste de la enfermedad. Los costes directos e indirectos se han estimado utilizando los costes de la prevalencia, es decir, los costes que se produjeron durante el año 1998. Los costes directos se han desglosado en costes de las hospitalizaciones, consultas externas, atención primaria y fármacos. Los indirectos se han obtenido a partir de unidades físicas mediante su transformación en unidades monetarias utilizando el enfoque de la teoría del capital humano y el método del período de fricción. Resultados: Los costes totales de las enfermedades cardiovasculares y del cáncer ascendieron a 246,11 y 193,72 millones de euros, respectivamente, utilizando el método del capital humano. Los costes directos atribuibles a las mismas fueron de 134,44 y 58,04 millones de euros, respectivamente, representando el 55 y 30% de los costes totales y el 16% del gasto total sanitario en esta región. Los costes indirectos de estas dos enfermedades ascendieron a 111,68 y 135,68 millones de euros, respectivamente, representando el 45 y 70% del total. Utilizando el método del período de fricción, los costes indirectos se redujeron en un 88% para enfermedades cardiovasculares y en un 77% en el cáncer. Conclusiones: A pesar de haberse adoptado un enfoque conservador, dado que en este estudio no se incluyen los costes asociados con el dolor y el sufrimiento, la invalidez permanente y la atención en el hogar por parte de los familiares, el elevado coste socioeconómico anual de las enfermedades cardiovasculares y del cáncer en Canarias alcanzó los 440 millones de euros.Objective: To evaluate the economic impact in terms of direct and indirect costs of the cardiovascular disease and cancer in the Canary Islands in 1998. Methods

  20. Northern fur seal pup production, adult male counts and harvest data for the Pribilof Islands, Alaska 1909 to Present

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This database contains information on pup production estimates, adult male counts and harvests (commercial and subsistence) for the Pribilof Islands of St. Paul and...

  1. Diffuse CO2 emission from the NE volcanic rift-zone of Tenerife (Canary Islands, Spain): a 15 years geochemical monitoring

    Science.gov (United States)

    Padilla, Germán; Alonso, Mar; Shoemaker, Trevor; Loisel, Ariane; Padrón, Eleazar; Hernández, Pedro A.; Pérez, Nemesio M.

    2016-04-01

    The North East Rift (NER) volcanic zone of Tenerife Island is one of the three volcanic rift-zones of the island (210 km2). The most recent eruptive activity along the NER volcanic zone took place in the 1704-1705 period with the volcanic eruptions of Siete Fuentes, Fasnia and Arafo volcanoes. The aim of this study was to report the results of a soil CO2 efflux survey undertaken in June 2015, with approximately 580 measuring sites. In-situ measurements of CO2 efflux from the surface environment of NER volcanic zone were performed by means of a portable non-dispersive infrared spectrophotometer (NDIR) model LICOR Li800 following the accumulation chamber method. To quantify the total CO2 emission from NER volcanic zone, soil CO2 efflux contour maps were constructed using sequential Gaussian simulation (sGs) as interpolation method. The total diffuse CO2 emission rate was estimated in 1209 t d-1, with CO2 efflux values ranging from non-detectable (˜0.5 g m-2 d-1) up to 123 g m-2 d-1, with an average value of 5.9 g m-2 d-1. If we compare these results with those obtained in previous surveys developed in a yearly basis, they reveal slightly variations from 2006 to 2015, with to pulses in the CO2 emission observed in 2007 and 2014. The main temporal variation in the total CO2 output does not seem to be masked by external variations. First peak precedes the anomalous seismicity registered in and around Tenerife Island between 2009 and 2011, suggesting stress-strain changes at depth as a possible cause for the observed changes in the total output of diffuse CO2 emission. Second peak could be related with futures changes in the seismicity. This study demonstrates the importance of performing soil CO2 efflux surveys as an effective surveillance volcanic tool.

  2. New Features in the Subsurface Structure Model of El Hierro Island (Canaries) from Low-Frequency Microseismic Sounding: An Insight into the 2011 Seismo-Volcanic Crisis

    Science.gov (United States)

    Gorbatikov, A. V.; Montesinos, F. G.; Arnoso, J.; Stepanova, M. Yu; Benavent, M.; Tsukanov, A. A.

    2013-07-01

    To study the deep structure of El Hierro Island, Canarian Archipelago, we have used a microseismic sounding method (MSM) based on the fact that heterogeneities of the Earth's crust disturb the spectrum of the low-frequency microseismic field in their vicinity. So, at the Earth's surface, the spectral amplitudes of definite frequency f above the high-velocity heterogeneities are decreasing, and above the low-velocity ones they are increasing. Moreover, the frequency f is connected with the depth of a heterogeneity H and the velocity of the fundamental mode of Rayleigh waves V R( f) through the relation H ≈ 0.4 V R( f)/ f. From these relations, the MSM lets us model the subsurface structure in a 3D context by inverting the amplitude-frequency spatial distribution of the microseismic field of low frequency. The validity of the method is shown through of numerical simulations and previous applications with known or verified solutions. This MSM is now used to invert the microseismic data registered in El Hierro Island. The obtained subsurface model reveals two large intrusive bodies beneath the island. Joint interpretation of microseismic and gravimetric data and their comparison with the available geological studies relate the central-eastern intrusive body to the early stage of the island formation. With respect to the western intrusive body, at the depths of 15-25 km, an area with lowest seismic velocities is identified, where we suggest that a modern magmatic reservoir is located. This reservoir could be associated with the recent submarine eruption in October 2011 and the accompanying seismic swarm, which started in July 2011. Several correlations between the shallowest structures identified by the gravity and MSM approaches are also found. Besides the numerical simulation and previous studies of this method, the correlation between gravity results, the MSM model, the geological information and the possible explanation of the features of the seismic swarm through

  3. Highly discrepant proportions of female and male Scandinavian and British Isles ancestry within the isolated population of the Faroe Islands

    DEFF Research Database (Denmark)

    Als, Thomas D; Jorgensen, Tove H; Børglum, Anders D;

    2006-01-01

    a frequency-based admixture approach taking private haplotypes into account by the use of phylogenetic information. While previous studies have suggested an excess of Scandinavian ancestry among the male settlers of the Faroe Islands, the current study indicates an excess of British Isles ancestry among...... the female settlers of the Faroe Islands. Compared to other admixed populations of the North Atlantic region, the population of the Faroe Islands appears to have the highest level of asymmetry in Scandinavian vs British Isles ancestry proportions among female and male settlers of the archipelago....

  4. Operating results of a wind-diesel system which supplies the full energy needs of an isolated village community in the Canary Islands

    Energy Technology Data Exchange (ETDEWEB)

    Carta, J.A. [Universidad de Las Palmas de Gran Canaria, Canary Islands (Spain). Departamento de Ingenieria Mecanica; Gonzalez, J. [Universidad de Las Palmas de Gran Canaria, Canary Islands (Spain). Departamento de Ingeniera Electronica y Automatica; Gomez, C. [Instituto Tecnologico de Canarias, Santa Lucia, Canary Islands (Spain). Departamento de Energias Renovables y Agua

    2003-01-01

    Following is a discussion of the operational strategies of a wind-diesel system which has been installed in an isolated fishing village community on the island of Fuerteventura in the Canarian Archipelago. The project was implemented with the aim of meeting the complete energy requirements of the community: street lighting and domestic consumption, desalination plant, freezer plant, sewage water purifier, hydrocompressor for the supply of potable water and a winch for small vessels. An analysis is also made of the results which were obtained with respect to the quality of the service supplied, the percentage of wind penetration in the system, fuel savings and the decrease of CO{sub 2} emissions into the atmosphere. A comparison of these results has also been made with the corresponding estimated figures for the performance of the system when originally designed. The conclusion is drawn that, from a technical point of view, the system that has been developed supplies all the service needs of the community on a regular basis with an acceptable level in the quality of the energy and a substantial improvement in the quality of the environment. This is a contributing factor to providing a satisfactory level in the quality of life for the inhabitants of the community. (author)

  5. Impact of Environmental Factors on the Spectral Characteristics of Lava Surfaces: Field Spectrometry of Basaltic Lava Flows on Tenerife, Canary Islands, Spain

    Directory of Open Access Journals (Sweden)

    Long Li

    2015-12-01

    Full Text Available We report on spectral reflectance measurements of basaltic lava flows on Tenerife Island, Spain. Lava flow surfaces of different ages, surface roughness and elevations were systematically measured using a field spectroradiometer operating in the range of 350–2500 nm. Surface roughness, oxidation and lichen coverage were documented at each measured site. Spectral properties vary with age and morphology of lava. Pre-historical lavas with no biological coverage show a prominent increase in spectral reflectance in the 400–760 nm range and a decrease in the 2140–2210 nm range. Pāhoehoe surfaces have higher reflectance values than ʻaʻā ones and attain a maximum reflectance at wavelengths < 760 nm. Lichen-covered lavas are characterized by multiple lichen-related absorption and reflection features. We demonstrate that oxidation and lichen growth are two major factors controlling spectra of Tenerife lava surfaces and, therefore, propose an oxidation index and a lichen index to quantify surface alterations of lava flows: (1 the oxidation index is based on the increase of the slope of the spectral profile from blue to red as the field-observed oxidation level strengthens; and (2 the lichen index is based on the spectral reflectance in the 1660–1725 nm range, which proves to be highly correlated with lichen coverage documented in the field. The two spectral indices are applied to Landsat ETM+ and Hyperion imagery of the study area for mapping oxidation and lichen coverage on lava surfaces, respectively. Hyperion is shown to be capable of discriminating different volcanic surfaces, i.e., tephra vs. lava and oxidized lava vs. lichen-covered lava. Our study highlights the value of field spectroscopic measurements to aid interpretation of lava flow characterization using satellite images and of the effects of environmental factors on lava surface evolution over time, and, therefore, has the potential to contribute to the mapping as well as dating

  6. Screening of emerging contaminants and priority substances (2008/105/EC) in reclaimed water for irrigation and groundwater in a volcanic aquifer (Gran Canaria, Canary Islands, Spain).

    Science.gov (United States)

    Estévez, Esmeralda; Cabrera, María del Carmen; Molina-Díaz, Antonio; Robles-Molina, José; Palacios-Díaz, María del Pino

    2012-09-01

    In semiarid regions, reclaimed water can be an important source of emerging pollutants in groundwater. In Gran Canaria Island, reclaimed water irrigation has been practiced for over thirty years and currently represents 8% of water resources. The aim of this study was to monitor contaminants of emerging concern and priority substances (2008/105/EC) in a volcanic aquifer in the NE of Gran Canaria where the Bandama Golf Course has been sprinkled with reclaimed water since 1976. Reclaimed water and groundwater were monitoring quarterly from July 2009 to May 2010. Only 43% of the 183 pollutants analysed were detected: 42 pharmaceuticals, 20 pesticides, 12 polyaromatic hydrocarbons, 2 volatile organic compounds and 2 flame retardants. The most frequent compounds were caffeine, nicotine, chlorpyrifos ethyl, fluorene, phenanthrene and pyrene. Concentrations were always below 50 ng L(-1), although some pharmaceuticals and one pesticide, cholrpyrifos ethyl, were occasionally detected at higher concentrations. This priority substance for surface water exceeded the maximum threshold (0.1 μg L(-1)) for pesticide concentration in groundwater (2006/118/EC). Sorption and degradation processes in soil account for more compounds being detected in reclaimed water than in groundwater, and that some contaminants were always detected in reclaimed water, but never in groundwater (flufenamic acid, propyphenazone, terbutryn and diazinon). Furthermore, erythromycin was always detected in reclaimed water (exceeding occasionally 0.1 μg L(-1)), and was detected only once in groundwater. In contrast, some compounds (phenylephrine, nifuroxazide and miconazole) never detected in reclaimed water, were always detected in groundwater. This fact and the same concentration range detected for the groups, regardless of the water origin, indicated alternative contaminant sources (septic tanks, agricultural practices and sewerage breaks). The widespread detection of high adsorption potential compounds

  7. Bimodal magmatism during the Diego Hernández Formation, Tenerife, Canary Islands: genesis and eruption-triggering of phonolitic magmas during ongoing mafic volcanism

    Science.gov (United States)

    Olin, P. H.; Wolff, J. A.; Edgar, C. J.; Cas, R.; Martí, J.

    2008-12-01

    The Diego Hernández Formation (DHF) represents the explosive eruption of nearly 70 cubic km of phonolite over approximately 200 k.y. from the Las Cañadas caldera on Tenerife. Four chemostratigraphic units are distinguished on the basis of trace element contents: DHF bs (represented by the 370 ka Fortaleza and 347 ka Roque Members), DHF I (319 ka Aldea, 309 ka Fasnia, and 268 ka Poris Members), DHF II (Arafo and 223 ka Caleta Members), and DHF III (Cruz Sequence and the 196 ka Abrigo Member); all named units involve plinian and/or ignimbrite components that devastated a significant fraction of the island [1]. These chemostratigraphic units demarcate two dominant compositional trends distinct in incompatible element contents, and in Nb/Ta and REE ratios. DHF bs and DHF III plot along a high-Nb trend, and DHF I and DHF II plot along a low-Nb trend, a feature consistent with divergent fractionation histories involving titanite. Mafic magma was an important component of the DHF magmatic system and flanking mafic volcanism was ongoing during DHF time. Major phonolitic eruptions are conformably bounded by basanitic lavas and scoria deposits. Mafic magmatic components are identifiable in many of the phonolitic pyroclastic deposits as mafic, mingled and banded pumices, or as quenched mafic enclaves. Mafic components in the Abrigo, Caleta, and Poris Members are nearly geochemically identical to the underlying scoria or lava, suggesting that flanking mafic volcanism may in some cases be associated with subcaldera intrusive events that remobilize phonolitic magma to trigger major explosive eruptions. We envisage that the DHF represents a time when the intrusion of mantle-derived mafic magma in the lower crust supplied heat sufficient for the generation of intermediate tephriphonolite and phonotephrite magmas via melting of gabbroic/basaltic crust. Some of these intermediate magmas evolved to phonolite by crystal fractionation, a scenario consistent with DHF III

  8. La llegada del offset a la prensa de Canarias: implicaciones en el tratamiento de la imagen The arrival of the offset printing system to the press in the Canary Islands: implications in the image treatment

    Directory of Open Access Journals (Sweden)

    Alberto Ardèvol Abreu

    2011-07-01

    Full Text Available El presente artículo forma parte de un trabajo de investigación más extenso sobre la evolución de la fotografía de prensa en Canarias desde el período 1975-1980 hasta la primera década del siglo XXI. Durante la segunda mitad de la década de 1970 se produjo en el archipiélago, de manera paulatina, la transición del sistema de impresión tipográfica al sistema offset. A través de estas páginas pretendemos analizar la influencia que tuvo en la fotografía de prensa de las islas la llegada de este nuevo sistema de impresión, que mejoró de manera significativa la calidad física de los periódicos del archipiélago. La impresión offset, mucho más limpia que su predecesora tipográfica, se publicitaba en Inglaterra bajo el lema “We don't print on your hand, we print on paper” (no imprimimos en sus manos, imprimimos el papel. Los cambios se llevaron a cabo de forma muy gradual, casi imperceptible en un primer momento, coincidiendo, además, con los años de transición política, y trajeron consigo modificaciones en la serie visual no lingüística (fotografías, dibujos, color..., así como en los restantes elementos del periódico, desde el formato al diseño, pasando incluso por los contenidos. Los resultados obtenidos se basan en el muestreo sistemático de dos de las cabeceras más importantes en aquellos momentos en las islas: El tinerfeño El Día y el vespertino Diario de Las Palmas.This article is part of a more extensive research on the evolution of press photography in the Canary Islands from the period 1975-1980 up to the first decade of the 21st century. In the second half of the 1970s it took place in the archipelago a gradually transition from the typographic printing system to the offset printing system. In these pages we try to analyze the influence that the arrival of this new printing system had in the photography of press of the islands, which improved in a significant way the physical quality of the Canarian

  9. COMPARATIVE ETHOGRAM OF MALE SEXUAL BEHAVIOUR OF RHODE ISLAND RED AND VANARAJA FOWL

    Directory of Open Access Journals (Sweden)

    A. Modhukoilya

    2012-01-01

    Full Text Available Experiment was conducted to compare the male sexual behaviour of Rhode Island Red and Vanaraja fowl parent stock managed under deep litter system. Twenty males and 140 females of each genetic group were selected randomly in two batches belonging to age and body weight ranges of 36-48 weeks & 2.8-4.5 kg respectively. Sexual behaviour was recorded for one hour starting at 5 PM. Every bird was observed for 20 sessions. The transformed data were analysed to identify the variation due to genetic group if any. Frequency of mounting in RIR and Vanaraja males are 1.80 ± 0.01 and 1.78 ± 0.01 respectively. Frequency (per hour of forced mounting is seen significantly (P 0.01 more in Vanaraja (1.93 ± 0.02 than that in RIR (1.77 ± 0.01. Frequency of copulation and forced copulation in RIR are 1.87 ± 0.01 and 1.62 ± 0.01 respectively; whereas in Vanaraja these values are 1.84 ± 0.01 and 1.63 ± 0.01. Frequency of male to male aggression does not differ significantly as the values are exactly the same in both genetic groups (2.29 ± 0.03. Frequency of male to female aggression in Vanaraja (2.64 ± 0.02 is significantly (P 0.05 more than that in RIR (2.56 ± 0.02. Frequency of waltzing pattern is seen significantly (P 0.01 more in RIR (2.10 ± 0.02 than in Vanaraja (1.95 ± 0.02. Frequency per hour of high step advance for both RIR and Vanaraja are 2.06 et al. 0.02 and 1.9 ± 0.02 respectively; Frequency per hour of steps off is seen more in RIR (2.00 ± 0.01 than that in Vanaraja (1.94 ± 0.01. Statistical analysis revealed significant effect of genetic group on steps off activity. It is concluded that RIR cocks appear to be more successful breeder. Vanaraja cocks have made more aggressive display of different patterns.

  10. En la población Canaria, la función de Framingham estima mejor el riesgo de mortalidad cardiovascular que la función SCORE Framingham function estimates the risk of cardio vascular mortality more effectively than SCORE function in the population of the Canary Islands (Spain

    Directory of Open Access Journals (Sweden)

    Antonio Cabrera de León

    2009-06-01

    /height razón, abdomen/pelvis ratio, and excessive alcohol consumption. Methods: We performed a cross-sectional study of 5,289 individuals aged 30 to 69 years old, recruited by random sampling of the general population of the Canary Islands. We calibrated the Framingham and SCORE functions and estimated their concordance. The cardiovascular mortality rate for the population in this age range was compared with the risk predicted by the two functions. Results: Among males, the mortality rate per 100,000 inhabitants was 67.4, while the Framingham, SCORE-low and SCORE-high estimations were 80, 140, and 270, respectively. Among females, the mortality rate was 19.3 while the estimations were 30, 50, and 70, respectively. Both functions detected the increased risk contributed by the factors studied, except for sedentariness among females with SCORE, and excessive alcohol consumption with both functions. Among males, taking cut points of > 12%, > 15%, and > 20% for Framingham, the concordance with SCORE-low yielded Kappa values of 0.6, 0.7, and 0.5, respectively. Conclusions: The Framingham function yielded the best estimate of cardiovascular mortality rates. Only Framingham detected the cardiovascular risk contributed by sedentariness in both genders. We recommend the use of the calibrated Framingham function for this population.

  11. Gravity and multichannel seismic reflection constraints on the lithospheric structure of the Canary Swell

    Science.gov (United States)

    Ranero, C. R.; Torne, M.; Banda, E.

    1995-12-01

    Deep penetrating multichannel seismic reflection and gravity data have been used to study the lithospheric structure of the Canary Swell. The seismic reflection data show the transition from undisturbed Jurassic oceanic crust, away from the Canary Islands, to an area of ocean crust strongly modified by the Canary volcanism (ACV). Outside the ACV the seismic records image a well layered sedimentary cover, underlined by a bright reflection from the top of the igneous basement and also relatively continuous reflections from the base of the crust. In the ACV the definition of the boundary between sedimentary cover and igneous basement and the crust-mantle boundary remains very loose. Two-dimensional gravity modelling in the area outside the influence of the Canary volcanism, where the reflection data constrain the structure of the ocean crust, suggests a thinning of the lithosphere. The base of the lithosphere rises from 100 km, about 400 km west of the ACV, to 80 km at the outer limit of the ACV. In addition, depth conversion of the seismic reflection data and unloading of the sediments indicate the presence of a regional depth anomaly of an extension similar to the lithospheric thinning inferred from gravity modelling. The depth anomaly associated with the swell, after correction for sediment weight, is about 500 m. We interpret the lithospheric thinning as an indication of reheating of old Mesozoic lithosphere beneath the Canary Basin and along with the depth anomaly as indicating a thermal rejuvenation of the lithosphere. We suggest that the most likely origin for the Canary Islands is a hot spot.

  12. Rut-induced changes in the activity budgets of male tropical ungulates: Eld's deer on Hainan Island

    Institute of Scientific and Technical Information of China (English)

    Jianhua DING; Zhitao LIU; Yanling SONG; Zhigao ZENG; Qiong ZHANG; Benjamin D.BRAVERY

    2012-01-01

    Aspects of time budgets,activity patterns and rut-related changes in behavior are well documented in temperate ungulates; however,the application of this understanding to tropical and sub-tropical ungulate species has attracted less attention and remains an area that may re-shape our knowledge of ungulate behavior.Eld's deer Cervus eldi hainanus has a tropical and sub-tropical distribution on Hainan Island,China,and males have an extended rut exceeding five months during which they do not maintain harems or defend resources.We studied males from the only remaining population on Hainan Island,and describe rut-related changes in behavior by collecting data on time budgets and activity patterns.We show that male Eld's deer do not follow a strict crepuscular activity pattern,do not spend the majority of their time foraging and do not increase foraging nor display rut-induced hypophagia during rut,in obvious contrast to temperate ungulates.These results are discussed in light of current hypotheses explaining the proximate mechanisms governing feeding time in ungulates,while appreciating the need for further research.

  13. Chemical characterisation of african dust transported to Canary Region

    Science.gov (United States)

    Gelado, M. D.; López, P.; Prieto, S.; Collado, C.; Hernández, J. J.

    2009-04-01

    African dust pulses have important effects on the climate conditions and the marine biogeochemistry in the Canary Region. Aerosol samples have been collected at three stations on Gran Canaria Island (Taliarte at sea level, Tafira 269 m a.s.l. and Pico de la Gorra 1930 m a.s.l.) during 2000-2008. Elemental characterisation of the collected mineral aerosol and back trajectories of the air masses are used to distinguish regional African sources of dust. Dust aerosol samples from North Sahara (Morocco, North Algeria and Tunisia), West and Central Sahara (20°-30°N, 18°W-50°E) and Sahel (0°-20°N, 18°W-50°E) have shown different Ca/Ti, Al/Ti and Fe/Al ratios. Ti appears as a better tracer element of specific source of dust than Fe, probably due to a less mineral alteration during the atmospheric transport.

  14. REE: Alkaline intensive and carbonates complexes at Fuerteventura (Canary Islands). Mineralizaciones de tierras raras: los complejos de rocas plutonicas alcalinas y carbonatitas del complejo basal de Fuerteventura (Islas Canarias)

    Energy Technology Data Exchange (ETDEWEB)

    Mangas Viuela, J.; Perez Torrado, F.J.

    1993-01-01

    Alkaline intrusive complexes at Fuerteventura have been explored as potential source of REE. Two main complexes constituted by ultramafic to salic rocks and carbonatitas are present in the island: the Puerto de la Pea-Cueva de Lobos (= 60 Ma) in the western centerpoint and the Esquinzo (=30 Ma) in the northern zone. The calciocarbonatites (sovites and alwikites), formed in the last crystallization phases of these complexes, show the highest values of REE (511-7,372 ppm) and these elements mainly are associated with carbonates (synchysite), phosphates (REE apatite), silicates (allanite). (Author) 17 refs.

  15. The canary in the mine.

    Science.gov (United States)

    Iezzoni, Lisa I

    2002-10-01

    Many Americans are concerned about their access to health care in the future, especially their ability to pay for needed services. However, a person with a disabling condition requiring ongoing clinical vigilance, supportive care, and other assistive services or technologies faces special difficulties: that person is the "canary in the mine," warning others about fundamental problems within our health care system. Persons with disabilities who have health insurance are often unable to get items and services not covered by their plans. They experience more problems than others with follow-up care, availability of specialists, getting to doctors, and obtaining help during off hours. These problems suggest that people with disabilities fall into the "quality chasm," the metaphor used by the Institute of Medicine to describe the gap between ideal care and current reality. The Crossing the Quality Chasm report suggests 6 aims for fundamental reform, exhorting the health care system to become safe, effective, patient-centered, timely, efficient, and equitable. Each of these aims holds special resonance for persons with disabilities. Despite the compelling need to overhaul the health care system, the American public as yet seems little inclined to fundamental change. Perhaps the impetus must come from subgroups within the population who are particularly at risk from the current system, such as persons with disabilities. As solutions are crafted, people with disabilities, their families, and communities should help design and direct fundamental changes to the health care system.

  16. Siliceous alterations of the Montana Senalo lavas, Timanfaya eruption (1730-1736) (Lanzarote, Canary Islands); Las alteraciones siliceas de las lavas de Montana Senalo, eruption de Timanfaya (1730-1736) (Lanzarote, Islas Canarias)

    Energy Technology Data Exchange (ETDEWEB)

    Carmona, J.; Romero, C.; Doniz, J.; Garcia, A.

    2009-07-01

    The presence of hydrothermal alterations within the lavas of Timanfaya eruption (1730-1736), with high proportions of quartz and opal, suggests the effective circulation of hot fluids. The source of these fluids would be located under the island, where silica would be dissolved from sandstones and radiolarites, moving this way towards the surface as Si(OH){sub 4} colloids. Study of opal indicates the presence of A-initial CT and C phases in the collected samples, which, considering the time needed for producing this phase transformations in the diagenetic evolution of opal (10,000-50,000 years), suggests an accelerating process, probably related with either the presence of fluid circulation or weathering processes. Such circumstances are necessary for explaining the presence of such components affecting 300 years old lavas. (Author) 36 refs.

  17. Systemic listeriosis in caged Canaries (Serinus canarius)

    OpenAIRE

    Akanbi, Olatunde B; Breithaupt, Angele; Polster, Ulf; Alter, Thomas; Quandt, Anette; Bracke, Andreas; Teifke, Jens Peter

    2009-01-01

    Abstract The occurrence of listeriosis in 12 caged canaries is described where 50 % of the birds including the female and all the offspring died within two weeks without clinical signs. At necropsy, multifocal necrotising and partly granulomatous hepatitis, splenitis, myocarditis, interstitial nephritis, and exudative pericarditis with intralesional Listeria monocytogenes were the predominant findings as shown by histopathology and immunohistochemistry. Microbiology, serology ...

  18. Influencia de la pérdida foliar sobre la cosecha en el cv. Gruesa, Musa acuminata Colla (AAA, cultivado bajo invernadero en las Islas Canarias Influence of leaf removal in yield of cv. Gruesa, Musa acuminata Colla (AAA, cultivated under greenhouse in the Canary Islands

    Directory of Open Access Journals (Sweden)

    Juan Cabrera Cabrera

    2010-12-01

    Full Text Available El cultivo de la variedad de platanera Gruesa, selección local de Dwarf Cavendish, ha experimentado un importante aumento en los últimos años en las Islas Canarias, tanto al aire libre como bajo invernadero. La eliminación de hojas, tras la floración, es una práctica habitual en los cultivos bajo invernadero. Asimismo es frecuente la pérdida de hojas por el efecto de los vientos en los cultivos al aire libre. El objetivo de este trabajo es evaluar, mediante simulación de pérdida foliar por daños mecánicos, la influencia que tiene la disminución de superficie foliar sobre el llenado y cosecha de la fruta en dicho cultivar. Para ello, cuatro meses antes de la cosecha se efectuaron cinco niveles de defoliación: 0%, 25%, 50%, 75% y 100%. Se valoran dos métodos diferentes de defoliación, eliminación de limbo foliar y tronchado de hojas con posterior corte de éstas. Se analizan y presentan datos morfológicos, fenológicos y productivos, así como valoración de la metodología empleada en este trabajo para la simulación de daños. A partir de un 25% de defoliado, equivalente a 7.5 hojas funcionales por planta, se detectaron diferencias significativas con las plantas testigos.The banana cultivar Gruesa, a local Dwarf Cavendish selection, is increasingly planted in the Canary Islands, both in greenhouse and in the open air. Both methods present some degree of leaf loss throughout the crop cycle: the leaves of greenhouse plants are traditionally cut back after flowering, and open air plantations experience frequent wind damage. A trial was set up four months prior to harvest to evaluate fruit filling rate and yield of Gruesa subjected to five levels of defoliation (0%, 25%, 50%, 75%, and 100% loss of leaf area. Two defoliation techniques were used to simulate damage: removal of the midrib, and slashing the leaf blade followed later by complete removal. Morphological, phenological and production data are presented.

  19. Wine tourism in the Canary Islands: An exploratory study

    Directory of Open Access Journals (Sweden)

    Abel Duarte Alonso

    2008-01-01

    Full Text Available Mientras el turismo del vino está desarrollándose en varias regiones vinícolas europeas, la evolución del mismo, o su potencial, en las Islas Canarias son poco conocidos. Este estudio exploratorio examina estas áreas entre 23 bodegas insulares. Los resultados revelan el potencial de desarrollo del turismo del vino en las islas, con bodegas que, o bien ya forman parte de este concepto, o planean acrecentar su participación. Los bodegueros entrevistados reconocen impedimentos que están frenando el desarrollo de la industria vinícola y del turismo del vino en las islas, incluyendo la competición de vinos foráneos y leyes del control de alcoholemia que inhiben el consumo del vino en bodegas entre los visitantes. Asimismo, los bodegueros perciben la necesidad de encontrar un balance entre el turismo en masa y el nicho del producto vinícola. Finalmente, el estudio propone áreas de futura investigación sobre el desarrollo del turismo del vino en Canarias.

  20. Geological history and within-island diversity: a debris avalanche and the Tenerife lizard Gallotia galloti.

    Science.gov (United States)

    Brown, Richard P; Hoskisson, Paul A; Welton, John-Henry; Báez, Marcos

    2006-10-01

    Several processes have been described that could explain geographical variation and speciation within small islands, including fragmentation of populations through volcanic eruptions. Massive landslides, or debris avalanches, could cause similar effects. Here we analyse the potential impact of the 0.8 million-year-ago (Ma) Güimar valley debris avalanche on the phylogeography of the lizard Gallotia galloti on the Canary Island of Tenerife. Distributions of mitochondrial DNA lineages (based on cytochrome b sequences) were analysed on a 60-km southeastern coast transect centred on this area. Three main clades were detected, which can be divided into northern (one clade) and southern (two clades) groups that introgress across the valley. Maximum-likelihood estimates of migration rates (scaled for mutation rate) revealed highly asymmetric patterns, indicating that long-term gene flow into this region from both the northern and the southern populations greatly exceeded that in the opposite directions, consistent with recolonization of the area. The ancestral Tenerife node on the G. galloti tree is estimated at 0.80 Ma, matching closely with the geological estimate for the debris avalanche. Morphological variation (body dimensions and scalation) was also analysed and indicated a stepped cline in female scalation across the valley, although the patterns for male scalation and male and female body dimensions were not as clear. Together these findings provide support for the hypothesis that the debris avalanche has shaped the phylogeography of G. galloti and may even have been a primary cause of the within-island cladogenesis through population fragmentation and isolation. Current estimates of timing of island unification mean that the original hypothesis that within-island diversity is explained by the secondary contact of populations from the two ancient precursor islands of Teno and Anaga is less plausible for this and some other Tenerife species. Large-scale landslides

  1. Systemic listeriosis in caged canaries (Serinus canarius).

    Science.gov (United States)

    Akanbi, Olatunde B; Breithaupt, Angele; Polster, Ulf; Alter, Thomas; Quandt, Anette; Bracke, Andreas; Teifke, Jens P

    2008-06-01

    The occurrence of listeriosis in 12 caged canaries is described where 50% of the birds, including the female and all of the offspring, died within 2 weeks without clinical signs. At necropsy, multifocal necrotizing and partly granulomatous hepatitis, splenitis, myocarditis, interstitial nephritis, and exudative pericarditis with intra-lesional Listeria monocytogenes were the predominant findings as shown by histopathology and immunohistochemistry. Microbiology, serology and polymerase chain reaction revealed L. monocytogenes serotype 1/2a as the causative agent. Thus listeriosis has to be considered in the differential diagnosis for granulomas associated with mycobacteriosis, yersiniosis, coligranulomatosis or fungal infections.

  2. Changes in infiltration rate into Andisols for change of use (Tenerife, Canary I.); Influencia del cambio de uso en la tasa de infiltracion de Andisoles (Tenerife, I. Canarias)

    Energy Technology Data Exchange (ETDEWEB)

    Neris, J.; Fuentes, J.; Dorta, M. A.; Jimenez, C.; Tejedor, M.

    2009-07-01

    The volcanic island of Tenerife (Canary Islands) has a wide variety of Andisols which have formed on recent pyroclast materials (Udands, Ustands, Xerands and Vitrands. The Udands are situated on the nor then side of the island, at heights where condensation of the trade winds occurs (900-1600m), while the Ustands are also located mostly on this side, albeit at a lower attitudinal strip. Under natural conditions, these soils present favourable physical properties, with high structural stability and resistance to water erosion. (Author) 11 refs.

  3. Positive co-occurrence of flea infestation at a low biological cost in two rodent hosts in the Canary archipelago.

    Science.gov (United States)

    Sánchez, S; Serrano, E; Gómez, M S; Feliu, C; Morand, S

    2014-04-01

    Non-random assemblages have been described as a common pattern of flea co-occurrence across mainland host species. However, to date, patterns of flea co-occurrence on islands are unknown. The present work investigates, on one hand, whether the decrease in the number of species on islands affects the pattern of flea co-occurrence, and on the other hand, how the cost of higher flea burdens affects host body mass. The study was carried out in the Canary Islands (Spain) using null models to analyse flea co-occurrence on Rattus rattus and Mus musculus. Results supported aggregation of flea species in Mus but not in Rattus, probably due to the relationship between abundance and both prevalence and intensity of infection of the main flea species parasitizing Mus. In addition, heavy individuals of both rodent species showed the highest flea burdens as well as higher species richness, probably due to the continued accumulation of fleas throughout life and/or immunological resistance mechanisms. Whatever the mechanisms involved, it is clear that co-occurrence and high parasite intensities do not imply a detrimental biological cost for the rodents of the Canary Islands.

  4. Análisis de costes y ahorros potenciales relacionados con la utilización de pruebas preoperatorias en los hospitales de Canarias Cost analysis and potential savings related to the use of preoperative tests in the hospitals of the Canary Islands [Spain

    Directory of Open Access Journals (Sweden)

    J. López-Bastida

    2003-04-01

    mejor selección y utilización de las pruebas preoperatorias.Objective: To estimate the potential cost savings that might take place in the Canary Islands Health Service (CHS through the appropriate scientific use of preoperative tests, using information obtained from five public university hospitals. Methods: A questionnaire was completed by 55 anesthesiologists, representing 60% of the total in the CHS. The questionnaire paid special attention to the most frequently used preoperative tests: chest radiograph, electrocardiogram, laboratory tests, and spirometry. The mean unit costs for the various preoperative tests were obtained from the two hospitals participating in the study. To calculate the potential cost savings derived from the appropriate use of preoperative tests, several scenarios were considered. These were characterized by different hypotheses or degrees of fulfillment of a protocol based on scientific knowledge and considered as the gold standard. Results: In the ideal scenario in which the recommended scientific protocol was fulfilled in 100% of the 16 179 patients with an American Society of Anesthesiologists (ASA grade of I-II, the economic impact would be notable, since it would free sensitive resources that could be used for other health programs. These figures could amount to approximately 1.02 million euros, without considering the cost of preoperative hospital stay. This figure could increase by up to approximately 2.13 million euros if one day of preoperative hospital stay were included and by up to 3.24 million euros if two days of preoperative hospital stay were included. Conclusions: The recent literature review and the results of the questionnaire applied in the CHS indicate that preoperative tests are of greatest benefit to patients and to society if their use is guided by scientific knowledge. In addition, resources can be freed by better selection and utilization of preoperative tests.

  5. Cryptorchestia ruffoi sp. n. from the island of Rhodes (Greece, revealed by morphological and phylogenetic analysis (Crustacea, Amphipoda, Talitridae

    Directory of Open Access Journals (Sweden)

    Domenico Davolos

    2017-02-01

    Full Text Available A new Cryptorchestia species, Cryptorchestia ruffoi Latella & Vonk, sp. n. from the island of Rhodes in south-eastern Greece, can be distinguished on the basis of morphological and phylogenetic data. Morphological analysis and DNA sequencing of mitochondrial and nuclear protein-coding genes indicated that this species is related to C. cavimana (Cyprus and C. garbinii (Mediterranean regions, with a recent northward expansion. Results supported a genetic separation between the Cryptorchestia species of the east Mediterranean regions and those of the northeast Atlantic volcanic islands examined in this study (C. canariensis, C. gomeri, C. guancha, and C. stocki from the Canary islands, C. monticola from Madeira, and C. chevreuxi from the Azores. The Mediterranean and Atlantic Cryptorchestia species appear to be also morphologically distinct. Cryptorchestia ruffoi sp. n., C. cavimana, C. garbinii, and C. kosswigi (Turkish coast clearly have a small lobe on the male gnathopod 1 merus. This character was the main diagnostic difference between Cryptorchestia (sensu Lowry, 2013 and Orchestia. However, among the six northeast Atlantic island Cryptorchestia species only C. stocki has a small lobe on the merus of gnathopod 1. Reduction or loss of the lobe in the Atlantic Island species cannot be ruled out; however, molecular phylogenetic analysis leads us to presume that this lobe independently evolved between the east Mediterranean Cryptorchestia species and C. stocki from Gran Canaria.

  6. Una aproximación etnográfica a las medianías de la isla de La Gomera: cultura, economía y movimientos migratorios = An ethnographic approach to mid-altitude settlements on the island of La Gomera, Canary Islands: culture, economy and migratory movements

    Directory of Open Access Journals (Sweden)

    García Alfonso, Patricia

    2016-09-01

    Full Text Available Resumen: El objetivo de este artículo es analizar los modos de vida, adaptación y los cambios sociales en diversos núcleos de población situados en las zonas de medianías de la isla de la Gomera; unos espacios que han mantenido el peso de la agricultura tradicional del campesinado. Desde una perspectiva etnográfica y partiendo de la identificación principalmente de los elementos asociados a los modos de producción y economía doméstica y política, se pretende configurar este universo simbólico. Las principales técnicas de obtención de datos han sido la observación participante y entrevistas semiestructuradas, reconstruyendo las etapas de vida de la población. De esta forma se muestra cómo los elementos de la infraestructura han tenido influencia en las condiciones de vida, aunque han sido los movimientos migratorios y el régimen de tenencia de tierras lo que ha determinado la evolución y la realidad actual de las medianías = Abstract: The aim of this article is to analyse lifestyle, adaptation and social change in various mid-altitude settlements on the island of La Gomera, areas in which traditional subsistence farming still prevails. In our attempt to construct this symbolic universe, we have taken an ethnographic perspective, focussing primarily on aspects related with modes of production and the domestic and political economy. Our main sources of data were participant observation and semi-structured interviews, which were used to reconstruct the different stages in the life of each settlement. This has enabled us to reflect how infrastructural factors have influenced living conditions, though the evolution and present-day reality of these mid-altitude settlements have been shaped by migratory movements and land ownership.

  7. Renewable energy islands in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Oestergaard, Iben [ed.

    1998-12-31

    This publication includes a compiled presentation of various aspects concerning the possible transformation of some European islands into renewable energy communities and these projects were presented by a selection of pioneer islands at the first European Seminar on Renewable Energy Islands, held on the Danish island of Samsoee, 29-30 June 1998. This issue has increased in importance with the presentation of the ambitious EU-White Paper: `Energy for the future: Renewable Sources of Energy` which was adopted in 1998. One of the key elements of the strategy for an accelerated implementation of renewable energy is to transform 100 localities within Europe into communities which are to be 100% self-sufficient with renewable energy before 2010. In line with this strategy, the Danish Government appointed the island of Samsoe towards the end of 1997 to be the first `official` Danish, renewable energy island. This is to serve as a demonstration project for other local communities, both in Denmark as well as in the rest Europe. Gothland, Madeira, Canary Islands, Cape Verde, Arki, Crete, Minorca and Orkney Islands were represented. Environmental advantages of wind, solar and wave power for distant island communities were indicated. Serious savings would be achieved by limitation of fossil fuel import and utilization of local resources. (EG)

  8. RRS "Charles Darwin" Cruise CD168, 02 Feb - 16 Feb 2005. Submarine landslides around the Cape Verde Islands

    OpenAIRE

    Masson, D. G.

    2005-01-01

    Catastrophic large-scale landslides are a fundamental process in the formation of many oceanic islands. The main aim of cruise CD168 was to carry out a reconnaissance survey of the influence of landsliding on the Cape Verde islands, in the eastern central Atlantic, and to compare this with the known effects of landsliding on the Canary Islands. The data collected during RRS Charles Darwin Cruise, when combined with synthetic aperture radar imagery of the subaerial islands, show clear evidence...

  9. Acute Megabacteriosis and Staphylococosis of Canary in Iran

    Directory of Open Access Journals (Sweden)

    Daryoush Babazadeh

    2015-03-01

    Full Text Available Megabacteriosis and staphylococosis are two important Infectious Diseases in Canary. Macrorhabdosis is a chronic progressively debilitating, gastrointestinal disease. Staphylococcus infections are common in poultry. Clinical signs are highly variable and dependent on site-organisms. Present case report describes the Megabacteriosis and staphylococosis in canary. A dead canary was referred to the clinic of veterinary medicine, university of Tehran, Iran That was lethargic and had watery white droppings for 4 days. The proventriculus was dilated and erosive lesions were seen. In wet smear prepared from proventriculus, Macrorhabdus ornithogaster was observed by light microscope. A purulent mass was detected in metatarsal joint, the gram staining of suspected mass determined the bird suffered from staphylococosis. Prescribed drugs for Megabacteriosis and Staphylococosis were nystatin and enrofloxacin respectively.

  10. A study of stomach contents of Cory's shearwater, Calonectris diomedea borealis (Cory, 1881) (Aves: Procellariidae), from the Macaronesian Islands

    NARCIS (Netherlands)

    Hartog, den J.C.; Clarke, M.R.

    1996-01-01

    Data are presented on the diet of Cory's Shearwater Calonectris diomedea borealis (Cory, 1881) resulting from stomach investigations based on 18 birds from Hierro (Canary Islands), 5 from Selvagem Grande (Selvagens or Salvage Islands), 2 from São Miguel and 1 from São Jorge (Azores), collected betwe

  11. Contribution à la Flore Mycologique des Iles Canaries

    NARCIS (Netherlands)

    Cool, Mlle C.

    1925-01-01

    Du 21 décembre 1922 au 13 mars 1923 je fis un séjour dans les îles Canaries, savoir: à Ténériffe (21 déc.—5 mars) et dans la Grande-Canarie (5—13 mars). Madame A. DEN TEX-BOISSEVAIN, ma compagne de voyage, séjourna encore et botanisa dans l’île de Palma du 19 février au 1 mars 1923. Bien que je fuss

  12. Upgraded fuel from reed canary grass

    Energy Technology Data Exchange (ETDEWEB)

    Heiskanen, V.P.

    1995-12-31

    The feasibility of RCG for commercial utilization depends primarily on its applicability for pulp production and its use in energy production will be based on the residue that will be available after extracting the pulp fraction of the RCG. Roughly 20 ..30% of the material will be available for energy production purposes. However, the percentage may be higher/lower depending on the quality standards of the pulp fiber material. The harvesting period has a significant effect on the fuel characteristics of RCG. For instance the contents of N, S, Cl, K are clearly lower if the RCG is harvested in the spring (delayed) instead of summer/autumn. These elements affect significantly overall emission formation and ash behaviour and its melting temperature. The combustion related research in this project has been focused on the spring-harvested RCG. The project aims to evaluate the feasibility of delayed harvested RCG for energy production. In order to reach this goal, the following combustion methods will be tested and studied: combustion of pelletized RCG; gasification; combustion of pulverized RCG. In addition, pelletizing, reactivity and NO conversion of pulverized RCG will be studied. The research described here is a part of `Reed Canary Grass` project (in AIR programme). The contractors of the project are Swedish University of Agricultural Sciences (coordinator), United Milling Systems from Denmark, Jaakko Poeyry Oy and VTT Energy. In addition, there are partners from several countries participating in the project. The project has been divided in five tasks, VTT Energy being responsible for combustion related task `Upgraded fuel` that includes the research topics discussed in this paper

  13. Phylogeography of Cape Verde Island skinks (Mabuya).

    Science.gov (United States)

    Brown, R P; Suarez, N M; Smith, A; Pestano, J

    2001-06-01

    The Cape Verde Islands are of volcanic origin with most having appeared between the early Miocene and mid-Pleistocene. They contain six known species of Mabuya skinks. Phylogeographical relationships within and among the relatively widespread taxa M. stangeri, M. spinalis and M. delalandii were inferred, based on approximately 1 kbp of the cytochrome b gene (mitochondrial DNA). Reciprocal monophyly of M. spinalis and M. stangeri was established, which may have arisen from an early Pliocene/late Miocene cladogenetic event. Considerable between-island sequence divergence was detected among M. spinalis, which appears to have colonized the older islands (Sal and Boavista) first. Much lower sequence divergence was found in M. delalandii, indicating a more recent range expansion. Here, evidence points to colonization of the younger islands of Brava and Fogo soon after appearance. There are similarities between some of the described patterns and those seen in lizards from the Canary Islands.

  14. Human enzyme polymorphism in the Canary Islands. III. Tenerife Island population.

    Science.gov (United States)

    Afonso, J M; Hernández, M; Larruga, J M; Cabrera, V M; González, A M

    1989-08-01

    We analyzed the genetic polymorphism of eight red cell enzymes in samples from different geographical areas of Tenerife and the Iberian peninsula. The gene frequency heterogeneity found within the Tenerife samples was at the same level as that of Tenerife-mainland comparisons. The presence of the Negroid G6PD A+ allele in the Tenerife samples is evidence of an African admixture with a mean estimation of 4.5%.

  15. Plant invasion and speciation along elevational gradients on the oceanic island La Palma, Canary Islands

    DEFF Research Database (Denmark)

    Steinbauer, Manuel; Irl, Severin David Howard; González-Mancebo, Juana Maria;

    2016-01-01

    Background: Ecosystems that provide environmental opportunities but are poor in species and functional richness generally support speciation as well as invasion processes. These processes are expected not to be equally effective along elevational gradients due to specific ecological, spatial...... and anthropogenic filters, thus controlling the dispersal and establishment of species. Here, we investigate speciation and invasion processes along elevational gradients. Methods: We assess the vascular plant species richness as well as the number and percentage of endemic species and non-native species...

  16. Chlamydia psittaci infection in canaries heavily infested by Dermanyssus gallinae.

    Science.gov (United States)

    Circella, Elena; Pugliese, N; Todisco, G; Cafiero, M A; Sparagano, O A E; Camarda, A

    2011-12-01

    Dermanyssus gallinae is a haematophagous ectoparasite responsible for anemia, weight loss, dermatitis and a decrease in egg production. Dermanyssus gallinae may play a role in the modulation of the host immune system, maybe predisposing the host to some bacterial infections such as chlamydiosis. This is an important zoonosis. Humans are exposed to Chlamydia psittaci through inhalation of the agent dispersed from the infected birds. In this study, a syndrome observed in an aviary of canaries was investigated. A heavy infestation by D. gallinae was reported. Simultaneously, a C. psittaci infection was molecularly confirmed in the canaries. Combined therapy was applied successfully. The association of C. psittaci with the examined mites has been confirmed. Therefore, we think that D. gallinae have played a role in the spreading of C. psittaci infection among the canaries. Moreover, D. gallinae could have played an important role predisposing the canaries to the development of chlamydiosis, by inducing anemia and debilitation. The control of mites in the aviaries may represent a crucial step for the prevention of important infection such as chlamydiosis in birds and humans.

  17. Frequency of CT studies performed in pediatric patients in the Canary University Hospital in the period 2005-2010; Frecuencia de los estudios de tomografia computerizada a pacientes pediatricos realizados en el hospital universitario de canarias en el periodo 2005-2010

    Energy Technology Data Exchange (ETDEWEB)

    Hdez Armas, O.; Glez Martin, A.; Bethencourt Pana, A.; Catalan Acosta, A.; Hdez Armas, J.

    2011-07-01

    This paper provides data for the number and diversity of computerized tomography scans performed on pediatric patients (<15 years) at the University Hospital of Tenerife (UHT), Canary Islands. The analysis of the frequency and trends of these medical procedures will make comparisons with the medical use of CT in other parts of Spain and the world.

  18. Torrefaction of pellets from reed canary grass and softwood

    Energy Technology Data Exchange (ETDEWEB)

    Oerberg, Haakan [Swedish Univ. of Agricultural Science, Unit for Biomass Technology and Chemistry, Umeaa (Sweden); Pommer, Linda; Nordwaeger, Martin; Olofsson, Ingemar [Umeaa Univ., Dept. of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry, Umeaa (Sweden)

    2012-11-01

    In this work an energy crop, Reed Canary Grass (RCG) has been studied in comparison with Norway Spruce (NS ) when treated in a torrefaction process. In the torrefaction process biomass is heated in an inert atmosphere (250-340 deg C) and physical and chemical characteristics are then enhanced and the product becomes more similar to coal. Co-firing of torrefied biomass with coal in existing CHP plants, and gasification of torrefied biomass has recently been demonstrated in industrial scale with positive results.

  19. Clinical and pathological findings of concurrent poxvirus lesions and aspergillosis infection in canaries

    Institute of Scientific and Technical Information of China (English)

    Kheirandish Reza; Askari Nasrin; Salehi Mahmoud

    2013-01-01

    Objective:To investigate clinical, pathological and mycological findings in canaries, in which pox lesions and Aspergillus fumigatus (A. fumigatus) infection were observed simultaneously. Methods:This study was performed on a breeding colony (about 100 canaries) affected by fatal wasting disease. Necropsy was undertaken on 10 severely affected canaries, and gross lesions were recorded. Samples from internal organs displaying lesions were obtained for histopathological evaluation. Tracheal swap samples of internal organs of the all infected animals with lesions at necropsy were cultured in Sabouraud Dextrose Agar for mycological examination. Results: At necropsy, caseous foci were determined in the lungs, on the air sacs, liver, spleen, heart. Swelling of the eyelids, diffuse hemorrhages in the subcutaneous tissue with small papular lesions of the skin were other typical necropsy findings. Histopathologically, pathognomonic eosinophilic intracytoplasmic inclusion bodies, which called Bollinger bodies, in both skin cells and vacuolated air way epithelial cells confirmed canary pox infection. Moreover, histopathological examination of the white-yellowish caseous foci revealed necrotic granulomatous reaction consisting of macrophages, heterophil leukocytes and giant cells encapsulated with a fibrous tissue. After the culture of the tissue samples, the formation of bluish green colonies confirmed A. fumigatus infection. Conclusions:Canary pox has been known as the disease that can result in high losses in a short time, as a re-emerging disease that has not been present during recent years in canary flocks in Iran. So, the current paper provides useful information to prevent misdiagnosed of canary pox disease which can cause secondary mycotic infection.

  20. Toward a Theory of Island Pedogeography: Testing the driving forces for pedological assemblages in archipelagos of different origins

    Science.gov (United States)

    Ibáñez, Juan-José; Effland, William R.

    2011-12-01

    The Theory of Island Biogeography has been based on biodiversity studies and used as a powerful predictive tool. Currently pedogeography does not have a similar theoretical construct. Although island biodiversity and biological assemblages have been topics of widespread interest in biogeography, ecology and conservation biology, soil scientists have conducted few studies of pedodiversity and pedological assemblages in archipelagos. Several studies have demonstrated that pedodiversity and biodiversity patterns have striking similarities in very disparate environments and at different scales, thus it is possible to test for a similar construct of island pedogeography. We analyze similarities and differences in the pedosphere for three archipelagos with different origins: (i) oceanic-intra-plate chains islands (Hawaiian Islands), (ii) oceanic-intra-plate cluster islands (Canary Islands), (iii) non-marine land-bridge islands with volcanism associated with plate boundary conditions (Aegean Islands) and (iv) as a comparison, islands in a nonplate boundary setting (the British Isles). In the Canary Islands, we also compiled selected biological, physiographical, geological and climatic data for further analysis of pedodiversity, climatic diversity, geodiversity and biodiversity. Our pedogeographic analysis of the three archipelagos indicates archipelagos of varying origins contain different soil assemblages with plate tectonics as the main driving force. The similarities between pedodiversity and biodiversity are more remarkable than the differences. We tested the hypothesis that soil taxa distributions on island chains can be modelled as a power function similar to the species-area relationship (SAR) proposed by McArthur and Wilson for archipelagos. The SAR functional relationship has been widely corroborated in other biodiversity studies. The same patterns were obtained for pedodiversity and biodiversity in the British Isles, and after that in the Aegean Archipelago. In

  1. DynaGuard: Armoring Canary-Based Protections against Brute-Force Attacks

    Science.gov (United States)

    2015-12-11

    Oriented Programming (ROP) [40]. For instance, the recently-introduced Blind ROP (BROP) [4] attack re- quires only a stack-based memory corruption...bookkeeping mechanism, our de- sign enables the runtime update of the canary value in all protected (active) stack frames of the running thread, so...information regarding where the canaries are located within the stack of each thread. There- fore, DynaGuard’s design should allow each running process to

  2. Labile carbon pools and biological activity in volcanic soils of the Canary Islands Fracciones de carbono orgánico lábil y actividad biológica en suelos de origen volcánico de las Islas Canarias Frações de carbono orgânico lábil e actividade biológica em solos de origem vulcânica das Ilhas Canárias

    Directory of Open Access Journals (Sweden)

    Cecilia María Armas Herrera

    2013-03-01

    Full Text Available It is important to assess the mineralisation of soil organic carbon (SOC to predict the short-term response of biosphere carbon reservoirs to changing environmental conditions. We investigated the labile (easily-mineralisable SOC in volcanic soils, where the bioavailability of SOC is typically affected by physico-chemical stabilisation mechanisms that are characteristic of these soils. Ten soils were selected that represent the most typical soil types (mainly Andosols and natural habitats (xerophytic scrubland, laurel forest and pine forest in the Canary Islands, a volcanic archipelago. Over two years we measured several physico-chemical SOC fractions with different degrees of bioavailability: water-soluble carbon in fresh soil samples (WSC and in the saturated extract (WSCse, hot water-extractable carbon (HWC, potassium sulphate-extractable carbon (PSC, microbial biomass carbon (MBC, particulate organic carbon (POC, humic substances carbon (HSC, and total organic carbon (TOC, and performed CO2 emission incubation assays. We related these measurements to the potential C inputs of plant litter and roots and to the activity of certain hydrolytic enzymes (CM-cellulase, ?-D-glucosidase, and dehydrogenase that are involved in carbon turnover. In vitro carbon mineralisation measurements from short assays (ten days were fitted with simple first-order kinetics to investigate SOC. This procedure was simple and allowed us to obtain estimates both for potentially mineralisable SOC and for the heterogeneity of the substrates that were consumed during incubation. The investigated volcanic soils had large labile SOC concentrations in which simple carbohydrates predominated and that were mainly derived from roots and aboveground non-woody residues. Among the analysed physico-chemical SOC fractions, HWC (3.1 g kg-1 on average at 0-30 cm depth in Andosols was the most correlated with C0 (1.2 g kg-1 and therefore best represents potentially mineralisable SOC. PSC

  3. A reconstruction of Palaeo-Macaronesia, with particular reference to the long-term biogeography of the Atlantic island laurel forests

    DEFF Research Database (Denmark)

    Fernández-Palacios, José María; de Nascimento, Lea; Otto, Rüdiger;

    2011-01-01

    Macaronesia is a biogeographical region comprising five Atlantic Oceanic archipelagos: the Azores, Madeira, Selvagen (Savage Islands), Canaries and Cape Verde. It has strong affinities with the Atlantic coast of the Iberian Peninsula and the north-western fringes of Africa. This paper re-evaluate...

  4. Differential characteristics in the chemical composition of bananas from Tenerife (Canary Islands) and Ecuador.

    Science.gov (United States)

    Forster, Markus Paul; Rodríguez Rodríguez, Elena; Díaz Romero, Carlos

    2002-12-18

    The contents of moisture, protein, ash, ascorbic acid, glucose, fructose, total sugars, and total and insoluble fiber were determined in cultivars of bananas (Gran Enana and Pequeña Enana) harvested in Tenerife and in bananas (Gran Enana) from Ecuador. The chemical compositions in the bananas from Tenerife and from Ecuador were clearly different. The cultivar did not influence the chemical composition, except for insoluble fiber content. Variations of the chemical composition were observed in the bananas from Tenerife according to cultivation method (greenhouse and outdoors), farming style (conventional and organic), and region of production (north and south). A highly significant (r = 0.995) correlation between glucose and fructose was observed. Correlations of ash and protein contents tend to separate the banana samples according to origin. A higher content of protein, ash, and ascorbic acid was observed as the length of the banana decreased. Applying factor analysis, the bananas from Ecuador were well separated from the bananas produced in Tenerife. An almost total differentiation (91.7%) between bananas from Tenerife and bananas from Ecuador was obtained by selecting protein, ash, and ascorbic acid content and applying stepwise discriminant analysis. By selecting the bananas Pequeña Enana and using discriminant analysis, a clear separation of the samples according to the region of production and farming style was observed.

  5. Paediatric drug prescribing. A comparison of Tenerife (Canary Islands, Spain) and Sweden.

    Science.gov (United States)

    Sanz, E J; Bergman, U; Dahlström, M

    1989-01-01

    The prescribing of medicines for ambulant children below 14 years of age has been compared between Tenerife (Spain) and Sweden. Data obtained from a random sample of 1327 children in a prospective study in Tenerife were compared with data from 3901 children in a Swedish survey linking diagnosis and therapy. Upper respiratory tract infection was the main diagnosis in both countries and antibiotics was the most frequently prescribed drug group (28.2% in Tenerife and 28.8% in Sweden). Half of the children in Sweden did not receive any medication, but only 10% of those in Tenerife did not receive a prescription. Children who received a prescription on average got 1.4 drugs in Sweden and 2.3 in Spain. Amongst the ten most commonly prescribed products in Sweden there were 11 active pharmacological principles as compared to 25 in Spain. These most frequently used preparations accounted for two thirds of all the prescriptions for children in Sweden and one third in Tenerife. In conclusion, drugs were significantly more often used to treat paediatric outpatients in Tenerife than in Sweden. The prescribing physician in Spain also chose a wider variety of drugs and more commonly used fixed combination products.

  6. Indications for solar influence on radon signal in the subsurface of Tenerife (Canary Islands, Spain)

    Science.gov (United States)

    Steinitz, G.; Martin-Luis, M. C.; Piatibratova, O.

    2015-05-01

    Radon at two locations in Tenerife is investigated. The MM-0 site is located in a bunker near Teide volcano. Daily radon (DR) signals are dominated by a 12-hour (S2) periodicity. Continuous wavelet transform (CWT) analysis of day-time and night-time series results in a day-night differentiation, which does not occur in the coeval temperature and pressure. This indicates that the radon system is directly affected by rotation of Earth around its axis, and not via the pressure and/or temperature pattern. San Fernando sites are in an underground gallery, located at 2.1 and 3 km from the entrance. Alpha and gamma time series show DR signals having an S1 and a strong S2 periodicity. Sidebands occur around the S1 periodicity. The lower sideband is close to 0.9972696 cycles per day (CPD; = sidereal frequency) and the upper sideband at a symmetric frequency above. They reflect a driver containing two waveforms having periodicities of rotation of Earth around its axis and around the Sun that influences radon in a non-linear fashion, leading to the sidebands around the S1 periodicity. Observation in Tenerife of sidebands and day-night phenomena substantiates the notion that the periodic components in the diurnal and annual frequency band of radon time series are due to the influence of a component in solar radiation.

  7. New xenophytes from Gran Canaria (Canary Islands, Spain, with emphasis on naturalized and (potentially invasive species

    Directory of Open Access Journals (Sweden)

    Verloove, F.

    2013-12-01

    Full Text Available Trabajos recientes de campo en Gran Canaria han facilitado el descubrimiento de nuevas localidades para plantas vasculares no nativas. Agave attenuata, Antigonon leptopus, Atriplex nummularia, Cascabela thevetia, Cenchrus echinatus, Cuscuta campestris, Diplachne fusca subsp. uninervia, Diplotaxis tenuifolia, Dysphania anthelmintica (hasta ahora confundida con D. ambrosioides, Eclipta prostrata, Euphorbia pulcherrima, Fagopyrum esculentum, Gossypium barbadense, Lablab purpureus, Lemna minuta, Opuntia leucotricha, Passiflora edulis, Pennisetum glaucum, Phaseolus acutifolius, Pluchea carolinensis, Prosopis juliflora, Salvia microphylla, Schinus terebinthifolius, Senna spectabilis, Solanum chrysotrichum, Tecoma stans, Tipuana tipu, Urochloa mutica, U. plantaginea y Washingtonia se citan por primera vez para las Islas Canarias, mientras que Alopecurus myosuroides, Amaranthus blitoides, Bothriochloa ischaemum var. songarica, Cardamine flexuosa subsp. debilis, Heliotropium curassavicum, Leonotis nepetifolia, Medicago lupulina, Parkinsonia aculeata, Physalis peruviana, Phytolacca americana y Turnera ulmifolia son nuevas para la flora de la isla de Gran Canaria. Finalmente, se confirma la presencia de Paspalum vaginatum, P. distichum y Cortaderia selloana en Gran Canaria.Trabajos recientes de campo en Gran Canaria han facilitado el descubrimiento de nuevas localidades para plantas vasculares no nativas. Agave attenuata, Antigonon leptopus, Atriplex nummularia, Cascabela thevetia, Cenchrus echinatus, Cuscuta campestris, Diplachne fusca subsp. uninervia, Diplotaxis tenuifolia, Dysphania anthelmintica (hasta ahora confundida con D. ambrosioides, Eclipta prostrata, Euphorbia pulcherrima, Fagopyrum esculentum, Gossypium barbadense, Lablab purpureus, Lemna minuta, Opuntia leucotricha, Passiflora edulis, Pennisetum glaucum, Phaseolus acutifolius, Pluchea carolinensis, Prosopis juliflora, Salvia microphylla, Schinus terebinthifolius, Senna spectabilis, Solanum chrysotrichum, Tecoma stans, Tipuana tipu, Urochloa mutica, U. plantaginea y Washingtonia se citan por primera vez para las Islas Canarias, mientras que Alopecurus myosuroides, Amaranthus blitoides, Bothriochloa ischaemum var. songarica, Cardamine flexuosa subsp. debilis, Heliotropium curassavicum, Leonotis nepetifolia, Medicago lupulina, Parkinsonia aculeata, Physalis peruviana, Phytolacca americana y Turnera ulmifolia son nuevas para la flora de la isla de Gran Canaria. Finalmente, se confirma la presencia de Paspalum vaginatum, P. distichum y Cortaderia selloana en Gran Canaria.

  8. Convection of geothermal fluids in the Timanfaya volcanic area, Lanzarote, Canary Islands

    Energy Technology Data Exchange (ETDEWEB)

    Arana, V.; Diez, J.L.; Ortiz, R.; Yuguero, J.

    1984-01-01

    A mathematical model has been derived to study the superficial thermal anomalies to be found in Lanzarote (605 C at 13 m depth) in association with the convection of geothermal fluids. The model is valid for a wide range of conditions, in particular for those found beneath the Timanfaya volcano (active between 1730 and 1736). Geological and geophysical data suggest that the heat source is related to a cylindrical magma body with a radius of 200 +/- 100 m and a top temperature of 850 +/- 100 C at a depth of 4 +/- 1 km. Energy is transported through fractures by magmatic volatiles and/or by water vapor coming from a deeply located water table: in such a convection system, a fluid flow of 10 1/m/sup 2/ day, which corresponds to a thermal flux of 130 W/m/sup 2/, is sufficient to explain the temperature anomalies observed at the surface. The relationships between gas flow and the surface temperatures, as well as the thermal gradients in the conducting fracture are also discussed. 27 references.

  9. New xenophytes from Gran Canaria (Canary Islands, Spain), with emphasis on naturalized and (potentially) invasive species

    OpenAIRE

    Verloove, F

    2013-01-01

    Trabajos recientes de campo en Gran Canaria han facilitado el descubrimiento de nuevas localidades para plantas vasculares no nativas. Agave attenuata, Antigonon leptopus, Atriplex nummularia, Cascabela thevetia, Cenchrus echinatus, Cuscuta campestris, Diplachne fusca subsp. uninervia, Diplotaxis tenuifolia, Dysphania anthelmintica (hasta ahora confundida con D. ambrosioides), Eclipta prostrata, Euphorbia pulcherrima, Fagopyrum esculentum, Gossypium barbadense, Lablab purpureus, Lemna minuta,...

  10. [SOCIODEMOGRAPHIC AND HEALTH CHARACTERISTICS ASSOCIATED WITH LOW BIRTH WEIGHT IN THE CANARY ISLANDS].

    Science.gov (United States)

    Bello Lujan, Luis M; Saavedra Santana, Pedro; Gutiérrez García, Luisa Esther; García Hernández, José Angel; Serra Majem, Lluis

    2015-10-01

    Introducción y objetivo: desde 1976, el término bajo peso al nacer (BPN) se aplica a todos los recién nacidos con un peso inferior a 2.500 g. y constituye el factor más importante que afecta a la mortalidad neonatal y a la morbilidad en la infancia. El objetivo de este trabajo es identificar las asociaciones entre los factores biológicos, socioeconómicos y sanitarios y el bajo peso en el recién nacido en las islas Canarias. Material y método: se realizó un estudio epidemiológico transversal, con los ficheros de las gestantes del 2011 y 2012 (n = 11,768) del Complejo Hospitalario Universitario Insular Materno de Gran Canaria, que representó el 66,3% de todos los partos de la provincia para esos años, excluyéndose del análisis los datos correspondientes a los embarazos múltiples (393) (3,3%). Se analizaron la distribución y la frecuencia del peso según características sociodemográficas; los porcentajes se compararon con el test de la 2, las medias con el t-test y las medianas con el test de Wilcoxon para datos independientes. Aquellas variables que mostraron asociación con el bajo peso en el análisis univariado fueron introducidas en un análisis logístico multidimensional. Resultados: en la distribución del peso al nacer se observó un exceso de niños con bajo peso (9,3%), de los cuales el 62,1% fueron pretérmino. Las madres de estos niños son más delgadas, de menor talla y tienen un IMC promedio de < 18,5 kg/m2, así como un promedio de edad de 31,5 años. Se observó igualmente que existe un incremento entre la edad de la madre y el bajo peso, aunque el efecto no es lineal; de hecho, los aumentos del riesgo de BPN se aceleran a medida que aumenta la edad. Cuando el IMC de la madre decrece, aproximadamente por debajo de 25, aumenta linealmente el riesgo de bajo peso. Las OR más elevadas corresponden al retraso fetal en el crecimiento intrauterino (CIR) (OR = 6,3; IC-95% = 5,3; 7,4), la hipertensión/eclampsia (OR = 3,2; IC-95% = 2,1; 5,1), la gestación menor de 37 semanas (OR = 2.,5; IC- 95% = 2,0; 3,3) y el consumo de tabaco de la madre (OR = 1,9; IC-95% = 1,6; 2,3). Conclusiones: el tabaquismo durante la gestación parece ser el factor mediador más importante para la restricción del crecimiento intrauterino. El sobrepeso u obesidad de la madre no parece que sean factores de riesgo para el bajo peso del niño. El crecimiento intrauterino restringido (CIR) es la variable sanitaria que más influye en el bajo peso, al igual que la hipertensión arterial de la madre, enfermedad asociada igualmente con el retraso en el crecimiento fetal. Aunque la falta de atención prenatal no puede considerarse como un factor causal del bajo peso, el 47,1% de las gestantes han tenido controles insuficientes (< de tres controles); con el aumento de los mismos se lograría reducir la frecuencia del bajo peso.

  11. [Importance of the school nurse's role in the Canary Islands schools].

    Science.gov (United States)

    Araujo, Pedro Jorge

    2013-01-01

    Today there are more and more children with chronic diseases or physical conditions that regularly attend schools. This study aims to identify the importance of school centers' directors attribute to the school nurse. It has been decided to make a cross-sectional study. So, it has been to sent by e-mail a questionnaire of 20 questions to 635 schools, receiving 209 completed. 65.6% of children in schools have required drugs administration. In 59.3% of schools, teachers have attended at one time any health problems (acute or chronic) of children. 98.1% of schools know the health problems of the students who is in charge. The most common health problem among children in schools were food allergies, followed by asthma, diabetes and epilepsy. 67% of school centers' directors know the guide attention to health emergencies in schools.

  12. Morphometric analysis of cinder cones on Tenerife (Canary Islands, Spain): results and applications

    Energy Technology Data Exchange (ETDEWEB)

    Doniz Paez, F. J.

    2009-07-01

    This paper applied morphometric to the cinder cones of Tenerife. The technical morphometric allows to establish simple models of morphology, and size to the most frequent volcanoes of Tenerife's mafic volcanism. The obtained classification allow to distinguish four morphological types of scoria cones and three size groups, which is also extended to other volcanic regions. (Author) 5 refs.

  13. Long-term volcanic hazard assessment on El Hierro (Canary Islands)

    OpenAIRE

    L. Becerril; S. Bartolini; R. Sobradelo; Martí, J.; Morales, J.M.; Galindo, I.

    2014-01-01

    Long-term hazard assessment, one of the bastions of risk-mitigation programs, is required for territorial planning and for developing emergency plans. To ensure qualitative and representative results, long-term volcanic hazard assessment requires several sequential steps to be completed, which include the compilation of geological and volcanological information, the characterization of past eruptions, spatial and temporal probabilistic studies, and the simulation of differ...

  14. Long-term volcanic hazard assessment on El Hierro (Canary Islands)

    OpenAIRE

    L. Becerril; S. Bartolini; R. Sobradelo; Martí, J.; Morales, J.M.; Galindo, I.

    2014-01-01

    Long-term hazard assessment, one of the bastions of risk-mitigation programs, is required for land-use planning and for developing emergency plans. To ensure quality and representative results, long-term volcanic hazard assessment requires several sequential steps to be completed, which include the compilation of geological and volcanological information, the characterisation of past eruptions, spatial and temporal probabilistic studies, and the simulation of different erupt...

  15. New Laparocerus Schoenherr, 1834 from the Canary Islands (Coleoptera, Curculionidae, Entiminae)

    OpenAIRE

    2016-01-01

    This contribution to the knowledge of the genus Laparocerus Schoenherr, 1834 deals with the pending descriptions of ten new species and six new subspecies, needed for the presentation of the phylogram of the Canarian-African clade, where these taxa are included.The new taxa are: Laparocerus auarita n. sp. from La Palma; L. gerodes n. sp., L. crotchi n. sp. and L. sanchezi arures n. ssp. from La Gomera; L. soniae n. sp. from Gran Canaria; and L. abona n. sp., L. tauce n. sp., L. sanctaecrucis ...

  16. Deposition of rheomorphic ignimbrite D (Mogán Formation), Gran Canaria, Canary Islands, Spain

    Science.gov (United States)

    Kobberger, Gustav; Schmincke, Hans-Ulrich

    Rheomorphic ignimbrite D (13.4Ma, Upper Mogán Formation on Gran Canaria), a multiple flow-single cooling unit, is divided into four major structural zones that differ in fabric and finite strain of deformed pyroclasts. Their structural characteristics indicate contrasting deformation mechanisms during rheomorphic flow. The zones are: (a) a basal zone (vitrophyre) with pure uniaxial flattening perpendicular to the foliation; (b) an overlying shear zone characterized by asymmetric fabrics and a significantly higher finite strain, with an ellipsoid geometry similar to stretched oblate bodies; (c) a central zone with a finite strain geometry similar to that of the underlying shear zone but without evidence of a rotational strain component; and (d) a slightly deformed to non-deformed top zone where the almost random orientation of subspherical pyroclasts suggests preservation of original, syn-depositional clast shapes. Rheomorphic flow in D is the result of syn- to post-depositional remobilization of a hot pyroclastic flow as shown by kinematic modeling based on: (a) the overall vertical structural zonation suggested by finite strain and fabric analysis; (b) the relation of shear sense to topography; (c) the interrelationship of the calculated vertical cooling progression at the base of the flow (formation of vitrophyre) and the related vertical changes in strain geometry; (d) the complex lithification history; and (e) the consequent mechanisms of deformational flow. Rheomorphic flow was caused by load pressure due to an increase in the vertical accumulation of pyroclastic material on a slope of generally 6-8°. We suggest that every level of newly deposited pyroclastic flow material of D first passed through a welding process that was dominated by compaction (pure flattening) before rheomorphic deformation started.

  17. The challenges of the Canary Islands' wine sector and its implications: A longitudinal study.

    Directory of Open Access Journals (Sweden)

    Abel Duarte Alonso

    2012-01-01

    Full Text Available Noticias y reportajes reconocen los retos a los que las regiones vinícolas españolas se enfrentan, incluyendo las Islas Canarias, donde las denominaciones de origen (DO existen desde hace menos de dos décadas. El presente estudio es una extensión de una investigación previa conducida en la industria vinícola de las islas, y profundiza en los hechos que están ocurriendo en el sector vitivinícola isleño. Dueños, enólogos y gerentes de 55 bodegas de seis islas que producen vinos participaron en entrevistas cara a cara y telefónicas. El sentimiento general entre los participantes es de seria preocupación, y los problemas actuales no parecen tener soluciones a corto plazo. El estudio presenta las posibles repercusiones de losresultados del estudio, incluyendo aquellos pertinentes al futuro del sector vitivinícola local, su cultura vinícola y tradición.

  18. Volcanic geomorphological classification of the cinder cones of Tenerife (Canary Islands, Spain)

    Science.gov (United States)

    Dóniz-Páez, J.

    2015-01-01

    This paper proposes a method to establish a morphological classification of Tenerife's cinder cones on the basis of a dual analysis of qualitative (existence, geometry and disposition of craters) and quantitative morphometric parameters (major and minor diameters and cone elongation, major and minor diameters and crater elongation). The result obtained is a morphological classification of the cinder cones of Tenerife, which can be sub-divided into four types: ring-shaped-cones, horseshoe-shaped-volcanoes, multiple volcanoes and volcanoes without crater. In Tenerife there is a clear dominance of horseshoe-shaped volcanoes (69.0%) over ring-shaped cones (13.1%), volcanoes without craters (11.4%) and multiple volcanoes (6.4%). The classification presented in this paper is characterized by its simplicity which makes it possible to include all morphological types of volcanoes found in Tenerife. This fact also renders our classification a useful tool to apply in other, both insular and continental volcanic areas to eventually analyze and systematize the study of eruptive edifices with similar traits.

  19. First report of southern Tomato virus in tomato in the Canary Islands, Spain

    NARCIS (Netherlands)

    Verbeek, M.; Dullemans, A.M.; Espino, A.; Botella, M.; Alfaro-Fernández, A.; Font, M.I.

    2015-01-01

    In October 2006, tomato plants with torrado disease were sampled in Spain. In a sample of cv. Mariana, originating from Gran Canaria, Tomato torrado virus (ToTV, genus Torradovirus) was detected (isolate GCN06; Alfaro-Fernández et al., 2010). In 2013, the sample was further analysed using next-gener

  20. A new genus and species of Aclididae (Gastropoda) from off Tenerife, Canary Islands

    NARCIS (Netherlands)

    Moolenbeek, R.G.; Warén, A.

    1987-01-01

    Dr. Manuel Carrillo Pèrez (Universidad de la Laguna) has sent some dredge-samples to the first author. This material contained many interesting molluscs, not mentioned by Nordsieck & Talavera (1979). Amongst them was a very peculiar gastropod species, which was difficult to identify. Based on some s

  1. Biogeographic ranges do not support niche theory in radiating Canary Island plant clades

    DEFF Research Database (Denmark)

    Steinbauer, Manuel; Field, Richard; Fernández-Palacios, José María

    2016-01-01

    in allopatry. Main conclusions: The expectations from niche conservatism were frequently not met; instead our results suggest considerable climatic niche lability. All significant differences in climatic niche differentiation were opposite to the predictions from competitive displacement. These forces may...

  2. Volcanic Alert System (VAS) developed during the (2011-2013) El Hierro (Canary Islands) volcanic process

    Science.gov (United States)

    Ortiz, Ramon; Berrocoso, Manuel; Marrero, Jose Manuel; Fernandez-Ros, Alberto; Prates, Gonçalo; De la Cruz-Reyna, Servando; Garcia, Alicia

    2014-05-01

    In volcanic areas with long repose periods (as El Hierro), recently installed monitoring networks offer no instrumental record of past eruptions nor experience in handling a volcanic crisis. Both conditions, uncertainty and inexperience, contribute to make the communication of hazard more difficult. In fact, in the initial phases of the unrest at El Hierro, the perception of volcanic risk was somewhat distorted, as even relatively low volcanic hazards caused a high political impact. The need of a Volcanic Alert System became then evident. In general, the Volcanic Alert System is comprised of the monitoring network, the software tools for the analysis of the observables, the management of the Volcanic Activity Level, and the assessment of the threat. The Volcanic Alert System presented here places special emphasis on phenomena associated to moderate eruptions, as well as on volcano-tectonic earthquakes and landslides, which in some cases, as in El Hierro, may be more destructive than an eruption itself. As part of the Volcanic Alert System, we introduce here the Volcanic Activity Level which continuously applies a routine analysis of monitoring data (particularly seismic and deformation data) to detect data trend changes or monitoring network failures. The data trend changes are quantified according to the Failure Forecast Method (FFM). When data changes and/or malfunctions are detected, by an automated watchdog, warnings are automatically issued to the Monitoring Scientific Team. Changes in the data patterns are then translated by the Monitoring Scientific Team into a simple Volcanic Activity Level, that is easy to use and understand by the scientists and technicians in charge for the technical management of the unrest. The main feature of the Volcanic Activity Level is its objectivity, as it does not depend on expert opinions, which are left to the Scientific Committee, and its capabilities for early detection of precursors. As a consequence of the El Hierro experience we consider the objectivity of the Volcanic Activity Level a powerful tool to focus the discussions in a Scientific Committee on the activity forecast and on the expected scenarios, rather than on the multiple explanations of the data fluctuations, which is one of the main sources of conflict in the Scientific Committee discussions. Although the Volcanic Alert System was designed specifically for the unrest episodes at El Hierro, the involved methodologies may be applied to other situations of unrest.

  3. [TOXIC RISK ASSESSMENT OF FLUORIDE PRESENCE IN BOTTLED WATER CONSUMPTION IN THE CANARY ISLANDS].

    Science.gov (United States)

    Jáudenes Marrero, Juan Ramón; Hardisson de la Torre, Arturo; Gutiérrez Fernández, Angel José; Rubio Armendáriz, Carmen; Revert Gironés, Consuelo

    2015-11-01

    Introducción: el flúor, como hormetina, es necesario en el organismo para evitar las caries, pero en cantidades excesivas puede llevar a efectos tóxicos adversos como la fluorosis dental o la fluorosis invalidante. Así, será importante no sobrepasar de forma crónica las IDR (Ingestas Diarias Recomendadas) para cada rango de edad y sexo. Se asume que la principal fuente de aporte de fluoruros es el agua. Objetivos: establecer las concentraciones de fluoruro en determinadas marcas de agua envasada que se consumen en Canarias, para renovar los datos ya desactualizados, y hacer la correspondiente evaluación del riesgo tóxico. Método: se han utilizado 25 muestras de siete marcas registradas y comercializadas diferentes, siendo analizadas mediante determinación potenciométrica con electrodo ion selectivo de fluoruro. Resultados: todas las marcas de agua analizadas cumplen con los criterios de calidad según la legislación actual española, ninguna puede considerarse “agua fluorada” y todas se pueden usar en la preparación de alimentos infantiles. Además, según las ingestas diarias de agua recomendadas por la EFSA para cada rango de edad, no se supera la IDR para ningún individuo mayor de cuatro años ni para ninguna de las marcas de agua analizadas. Conclusiones: las aguas envasadas producidas en Canarias tienen niveles de fluoruro similares a las producidas en la península (todas en un rango de 0,24 a 0,62 mg/L). Los individuos sobre los que recaen las restricciones más amplias de consumo de agua son los menores de un año, pero en cualquier caso, a medida que el individuo crece va aumentando la permisibilidad del aporte de fluoruros (aumenta hasta los 19 años) y, por tanto, aumenta la variedad de aguas envasadas que se pueden consumir sin superar la IDR. En ciertos lugares de la Comunidad Autónoma Canaria sería recomendable consumir agua envasada respecto al agua de abastecimiento público.

  4. Anchialine fauna of the Corona lava tunnel (Lanzarote,Canary Islands): diversity, endemism and distribution

    DEFF Research Database (Denmark)

    Martínez, Alexandro; Palmero, A M; Brito, M C;

    2009-01-01

    A checklist of 77 taxa recorded from the anchialine sections of the Corona lava tube is provided, including information on habitats, faunal distribution within the cave, and main references. Of the nine major groups recorded, Crustacea shows the highest diversity with 31 species and the highest...

  5. Complex Explosive Phonolitic Volcanism From Tenerife, Canary Islands: the Diego Hernandez Formation

    Science.gov (United States)

    Olin, P. H.; Edgar, C. J.; Wolff, J. A.; Nichols, H. J.; Cas, R.; Marti, J.

    2001-12-01

    The Diego Hernandez Formation (DHF) consists of several phonolitic pyroclastic packages erupted between 0.53 and 0.196 Ma. Here we focus on the most intense period of DHF explosive phonolitic activity, from 0.32 - 0.28 Ma, during which three major plinian sequences with intraplinian ignimbrites, respectively the Aldea (0.320 +/- 0.008 Ma), Fasnia (0.309 +/- 0.012 Ma) and Poris Members (0.276 +/- 0.016 Ma) were emplaced. A minor disconformity, representing a pause of perhaps a few weeks' duration, separates lower and upper parts of the Fasnia Member. Volumes are difficult to estimate due to substantial offshore deposition, but each of the three has a minimum volume of a few cubic kilometers DRE. The dominant phonolite component in all three units shows broad chemical variations that suggest a similar magmatic lineage. However, details of trace element covariations do not support evolution of phonolite from a common parent, while the order of extraction of different compositions within a single eruption is complex. The Aldea and the lower Fasnia contain highly evolved phonolitic pumice (Zr up to 2,000 ppm), variably mixed with mafic and intermediate magmatic components. Plinian fall units in the upper Fasnia have little admixed mafic material yet are significantly less evolved than preceeding units (Zr = 850 - 1500 ppm), and show overall normal compositional zoning. However, highly evolved phonolite reappears towards the end of the Fasnia eruption sequence, and is more abundant in interbedded ignimbrites than in plinian fall units. The Poris Member contains phonolite similar to the least evolved compositions in the upper Fasnia, with a minor population of a much less differentiated phonolite (Zr = 600 - 650 ppm) that has little affinity with the the rest of the sequence, but resembles magmas erupted during a later DHF cycle. Both Poris phonolite types mingled with basaltic liquid. The repeated eruption of multiple felsic magmas with distinct trace element signatures, variably mixed with mafic magma, points to a model for DHF magmatism of co-existing phonolitic magma bodies that are periodically mobilized by injection of mafic magma.

  6. Production rates of 36Cl in basalts from the calibration site of Fuerteventura, Canary Islands

    NARCIS (Netherlands)

    Mai, K.

    2009-01-01

    Age determination based on cosmogenic nuclides is an important tool to investigate landscape development and age relations of geologically very young materials. The aim of this study is to contribute data to establish age determination of the basis of cosmogenic 36Cl production as a generally reliab

  7. On the Confession of a Canary Bird, Children on a Holiday Camp, and the Apology for Fleas Planned by Janusz Korczak

    Directory of Open Access Journals (Sweden)

    Agnieszka Zgrzywa

    2013-01-01

    Full Text Available The point of departure for this article is the memory of moving fragments of Janusz Korczak’s journal from Warsaw ghetto. The author confronts the fragments with Korczak’s earlier texts, such as the short storied about holiday camps for Polish and Jewish children, and the novel Król Maciuś na bezludnej wyspie [King Maciuś on a Desert Island]. The image of a canary bird, used in the novel, is confronted with other symbolic stories about this bird, such as the story in Wiesław Myśliwski’s Pałac [Palace]. With reference to the image, the article invokes Korczak’s meditations on identity and tolerance, and human ethical and aesthetic choices. The audacity of Korczak’s thoughts and conclusions goes far beyond his time, and seems perfectly fit for ours.

  8. Accumulating pollutants in conifer needles on an Atlantic island - a case study with Pinus canariensis on Tenerife, Canary Islands.

    Science.gov (United States)

    Tausz, Michael; Trummer, Walter; Goessler, Walter; Wonisch, Astrid; Grill, Dieter; Naumann, Simone; Jiménez, Maria Soledad; Morales, Domingo

    2005-08-01

    Concentrations of potential pollutant elements Na, Cl, and S were investigated in needles of Pinus canariensis grown at 55 field plots in Tenerife. Microelement concentrations (including heavy metals) were measured at a subset of 18 plots. Na and Cl concentrations were high at low elevations (up to 8 mg g(-1) Cl and 5.5 mg g(-1) Na). Na/Cl ratio close to standard seawater indicated sea spray influence up to 1200 m a.s.l. Only at few plots, sulphur concentrations indicated possible pollutant impact. Cluster and correlation analyses identified a related group of V, As, Cr, Fe, Mo, Ni, Cu, Pb, and Al, possibly related to traffic exhaust aggregated with soil particles. Mainly north-eastern, lower elevated plots were exposed to those immissions, but metal concentrations were generally low compared to data from other studies. In conclusion, seawater and soil particles explained most of the element distribution pattern in pine needles in Tenerife, but strong indications for some effect of local sources of air pollutants were detected.

  9. Accumulating pollutants in conifer needles on an Atlantic island - A case study with Pinus canariensis on Tenerife, Canary Islands

    Energy Technology Data Exchange (ETDEWEB)

    Tausz, Michael [School of Forest and Ecosystem Science, University of Melbourne, Water Street, Creswick, Victoria 3363 (Australia); Karl-Franzens Universitaet Graz, Institut fuer Pflanzenwissenschaften, Schubertstrasse 51, A-8010 Graz (Austria)]. E-mail: michael.tausz@uni-graz.at; Trummer, Walter [Karl-Franzens Universitaet Graz, Institut fuer Pflanzenwissenschaften, Schubertstrasse 51, A-8010 Graz (Austria); Goessler, Walter [Karl-Franzens Universitaet Graz, Institut fuer Chemie, Analytische Chemie, Universitaetsplatz 1, A-8010 Graz (Austria); Wonisch, Astrid [Karl-Franzens Universitaet Graz, Institut fuer Pflanzenwissenschaften, Schubertstrasse 51, A-8010 Graz (Austria); Grill, Dieter [Karl-Franzens Universitaet Graz, Institut fuer Pflanzenwissenschaften, Schubertstrasse 51, A-8010 Graz (Austria); Naumann, Simone [Universitaet Karlsruhe (TH), Institut fuer Geographie und Geooekologie, Kaiserstrasse 12, Geb. 10.50, D-76128 Karlsruhe (Germany); Jimenez, Maria Soledad [Universidad de La Laguna, Departamento de Biologia Vegetal, Fisiologia Vegetal, E-38207 La Laguna, Tenerife (Spain); Morales, Domingo [Universidad de La Laguna, Departamento de Biologia Vegetal, Fisiologia Vegetal, E-38207 La Laguna, Tenerife (Spain)

    2005-08-15

    Concentrations of potential pollutant elements Na, Cl, and S were investigated in needles of Pinus canariensis grown at 55 field plots in Tenerife. Microelement concentrations (including heavy metals) were measured at a subset of 18 plots. Na and Cl concentrations were high at low elevations (up to 8 mg g{sup -1} Cl and 5.5 mg g{sup -1} Na). Na/Cl ratio close to standard seawater indicated sea spray influence up to 1200 m a.s.l. Only at few plots, sulphur concentrations indicated possible pollutant impact. Cluster and correlation analyses identified a related group of V, As, Cr, Fe, Mo, Ni, Cu, Pb, and Al, possibly related to traffic exhaust aggregated with soil particles. Mainly north-eastern, lower elevated plots were exposed to those immissions, but metal concentrations were generally low compared to data from other studies. In conclusion, seawater and soil particles explained most of the element distribution pattern in pine needles in Tenerife, but strong indications for some effect of local sources of air pollutants were detected. - Pollutant concentrations in pine needles indicate moderate local impact of sulphur, particulate matter, and sea sprays at lower elevation plots in Tenerife.

  10. CanariCam/GTC observations of (99942) Apophis

    CERN Document Server

    Licandro, J; Alvarez, C; Alí-Lagoa, V; Delbò, M

    2015-01-01

    The potentially hazardous asteroid (PHA) (99942) Apophis is one of the most remarkable near-Earth asteroids (NEA) in terms of impact hazard. A good determination of its surface thermal inertia is very important in order to evaluate the Yarkovsky effect on its orbital evolution. We present thermal infrared observations obtained on January 29, 2013, with CanariCam mid-infrared camera/spectrograph attached to the Gran Telescopio CANARIAS (GTC, Roque de los Muchachos Observatory, La Palma, Spain) using the Si2-8.7, Si6-12.5, and Q1-17.65 filters with the aim of deriving Apophis' diameter ($D$), geometric albedo ($p_V$), and thermal inertia ($\\Gamma$). We performed a detailed thermophysical model analysis of the GTC data combined with previously published thermal data obtained using Herschel Space Observatory PACS instrument at 70, 100, and 160 $\\mu$m.The thermophysical model fit of the data favors low surface roughness solutions (within a range of roughness slope angles $rms$ between 0.1 and 0.5), and constrains ...

  11. Large eruption-triggered ocean-island landslide at Tenerife

    DEFF Research Database (Denmark)

    Harris, P; Branney, M; Storey, Michael

    2011-01-01

    An extensive debris-avalanche deposit has been discovered on Cañadas volcano, Tenerife (Canary Islands). The onshore component of the 733 ± 3 ka Abona landslide deposit exposes classic block facies and mixed facies across 90 km2. Three lines of evidence together show that the avalanche was trigge......, and created a major breach that affected the passage of destructive pyroclastic density currents on Tenerife for 0.5 m.y., showing that landslides can have enduring consequences for pyroclastic dispersal and hazards....

  12. CANARY phase B: on-sky open-loop tomographic LGS AO results

    Science.gov (United States)

    Morris, Tim; Gendron, Eric; Basden, Alastair; Martin, Olivier; Osborn, James; Henry, David; Hubert, Zoltan; Sivo, Gaetano; Gratadour, Damien; Chemla, Fanny; Sevin, Arnaud; Cohen, Matthieu; Younger, Eddy; Vidal, Fabrice; Wilson, Richard; Butterley, Tim; Bitenc, Urban; Reeves, Andrew; Bharmal, Nazim; Raynaud, Henri-François; Kulcsar, Caroline; Conan, Jean-Marc; Huet, Jean-Michel; Perret, Denis; Dickson, Colin; Atkinson, David; Bailie, Tom; Longmore, Andy; Todd, Stephen; Talbot, Gordon; Morris, Simon; Rousset, Gérard; Myers, Richard

    2014-07-01

    CANARY is an on-sky Laser Guide Star (LGS) tomographic AO demonstrator that has been in operation at the 4.2m William Herschel Telescope (WHT) in La Palma since 2010. In 2013, CANARY was upgraded from its initial configuration that used three off-axis Natural Guide Stars (NGS) through the inclusion of four off-axis Rayleigh LGS and associated wavefront sensing system. Here we present the system and analysis of the on-sky results obtained at the WHT between May and September 2014. Finally we present results from the final `Phase C' CANARY system that aims to recreate the tomographic configuration to emulate the expected tomographic AO configuration of both the AOF at the VLT and E-ELT.

  13. Galapagos Islands

    Science.gov (United States)

    2002-01-01

    This true-color image of the Galapagos Islands was acquired on March 12, 2002, by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra satellite. The Galapagos Islands, which are part of Ecuador, sit in the Pacific Ocean about 1000 km (620 miles) west of South America. As the three craters on the largest island (Isabela Island) suggest, the archipelago was created by volcanic eruptions, which took place millions of years ago. Unlike most remote islands in the Pacific, the Galapagos have gone relatively untouched by humans over the past few millennia. As a result, many unique species have continued to thrive on the islands. Over 95 percent of the islands' reptile species and nearly three quarters of its land bird species cannot be found anywhere else in the world. Two of the more well known are the Galapagos giant tortoise and marine iguanas. The unhindered evolutionary development of the islands' species inspired Charles Darwin to begin The Origin of Species eight years after his visit there. To preserve the unique wildlife on the islands, the Ecuadorian government made the entire archipelago a national park in 1959. Each year roughly 60,000 tourists visit these islands to experience what Darwin did over a century and a half ago. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  14. The conditions for use of reed canary grass briquettes and chopped reed canary grass in small heating plants; Foerutsaettningar foer anvaendning av roerflensbriketter och hackad roerflen i mindre vaermecentraler

    Energy Technology Data Exchange (ETDEWEB)

    Paulrud, Susanne; Davidsson, Kent; Holmgren, Magnus A. (Swedish National Testing and Research Inst., Boraas (Sweden)); Hedman, Henry; Oehman, Rikard; Leffler, Joel (ETC, Piteaa (Sweden))

    2010-09-15

    The aim of this study was to test fuel blends of briquettes and chopped reed canary grass in three existing heating plants (50 kW - 500 kW) and elucidate the requirements for good performance and low emissions. In addition, the study investigated production of reed canary grass briquettes using a Polish screw press developed for straw. Some tests with a bale shredder were also undertaken. The screw press technique is of interest for reed canary grass because it is a simple technique, easy to handle, developed for small scale production, and for straw. The test with reed canary grass in this study showed that the technique worked well but that further adjustments and a longer test period are needed in order to achieve higher bulk density and mechanical strength. The test with chopped reed canary grass shows that a system with a forage harvester is slightly more effective than baling and cutting in a bale shredder. The study concluded that few existing heating plants of size 50 kW-1 MW that currently use wood fuels will be able to use reed canary grass without adjustment, conversion or replacement of the combustion equipment. Reed canary grass has 15-20 times higher ash content than wood briquettes and 2-3 times higher ash content than forest residue; the combustion equipment must be able to handle these properties. The boiler must be equipped with a continuously operating ashing system and it must be possible to move the ash bed mechanically. There is a risk of high content of unburned matter if the residence time in the boiler is too short, due to the structure and low bulk density of the reed canary grass ash. Using a blend of wood briquettes and reed canary briquettes results in lower ash content, but also affects the ash chemistry and tends to lower the initial ash fusion temperature compared to using 100 % reed canary grass. Blending chopped reed canary grass and wood chips in an existing small scale heating plant also requires measures to achieve an even fuel

  15. Monocotyledons in Particleboard Production: Adhesives, Additives, and Surface Modification of Reed Canary Grass

    Directory of Open Access Journals (Sweden)

    Johann Trischler

    2014-05-01

    Full Text Available As a supplier to the furniture industry, the particleboard industry is searching for opportunities to reduce costs, weight, and formaldehyde emissions. One such opportunity is to use monocotyledons such as straw and hemp, as well as grasses like reed canary grass. A major problem when using reed canary grass or other monocotyledons in combination with wood is the difference in their surface properties, leading to poor reactivity and wettability with adhesives such as melamine urea formaldehyde. To this end, either the surface of the particles must be modified in some way, or different adhesives must be used. The purpose of this paper is to present adhesives, surfactants, coupling agents, and pre-treatment methods that can be used in combination with monocotyledons to improve compatibility with wood. Some of the methods have been tested on reed canary grass. The results show a wide range of strength values for the joint between wood and untreated or pre-treated reed canary grass glued with different adhesives, with and without a surfactant and a coupling agent. Isocyanate-based adhesives provided relatively strong bonds, and polyvinyl acetate, acryl, and epoxy adhesives were also effective. The most effective method was pre-treatment followed by adhesives in combination with a coupling agent.

  16. Co-variance of dissolved Fe-binding ligands with phytoplankton characteristics in the Canary Basin

    NARCIS (Netherlands)

    Gerringa, L. J. A.; Veldhuis, M. J. W.; Timmermans, K. R.; Sarthou, G.; de Baar, H. J. W.

    2006-01-01

    Dissolved Fe and ligand concentrations and the Fe-binding strength of the organic ligands were measured in samples from the upper water column (150 m) of the oligotrophic waters of the Canary Basin (eastern North Atlantic Ocean). Concentrations of major nutrients, phytoplankton abundance and photosy

  17. Identification and antimicrobial resistance of members from the Enterobacteriaceae family isolated from canaries (Serinus canaria

    Directory of Open Access Journals (Sweden)

    Ruben V. Horn

    2015-06-01

    Full Text Available Abstract: The Enterobacteriaceae family contains potentially zoonotic bacteria, and their presence in canaries is often reported, though the current status of these in bird flocks is unknown. Therefore, this study aimed to identify the most common genera of enterobacteria from canaries (Serinus canaria and their antimicrobial resistance profiles. From February to June of 2013, a total of 387 cloacal swab samples from eight domiciliary breeding locations of Fortaleza city, Brazil, were collected and 58 necropsies were performed in canaries, which belonged to the Laboratory of Ornithological Studies. The samples were submitted to microbiological procedure using buffered peptone water and MacConkey agar. Colonies were selected according to their morphological characteristics on selective agar and submitted for biochemical identification and antimicrobial susceptibility. A total of 61 isolates were obtained, of which 42 were from cloacal swabs and 19 from necropsies. The most isolated bacteria was Escherichia coli with twenty five strains, followed by fourteen Klebsiellaspp., twelve Enterobacterspp., seven Pantoea agglomerans, two Serratiaspp. and one Proteus mirabilis. The antimicrobial to which the strains presented most resistance was sulfonamides with 55.7%, followed by ampicillin with 54.1% and tetracycline with 39.3%. The total of multidrug-resistant bacteria (MDR was 34 (55.7%. In conclusion, canaries harbor members of the Enterobacteriaceae family and common strains present a high antimicrobial resistance rate, with a high frequency of MDR bacteria.

  18. Molecular epidemiology of systemic Salmonella enterica serovar Typhimurium outbreak in canaries

    Directory of Open Access Journals (Sweden)

    I Ashrafi Tamai

    2009-12-01

    Full Text Available Background and Objectives: In May 2007, high mortality with severe septicemia was reported in 17 flocks of canaries in"ndifferent regions of Tehran province. This study was designed to follow up and study a great outbreak of salmonellosis in"nthese canaries."nMaterials and Methods: Two carcasses from every flock, environment, food and water resources were examined. After"nisolating the bacteria, serotyping and multiplex PCR were performed to confirm the bacteria identified. The isolates within the"nsame serovars were investigated by R-typing using 33 antibiotics and then subjected to RAPD-PCR with three primers. The"ngenomic DNA from these isolates were digested with XbaІ and the macro restriction fragment were separated by PFGE."nResults: S. Typhimurium was isolated from dead carcasses, visceral organs, stools and feed. Thirty-six isolated strains (35"nisolates from canary carcasses and one isolate from feed showed similar results in all of the tests, confirming the occurrence"nof an outbreak."nConclusion: Canaries seem to be very susceptible to infection with S. Typhimurium. The clonality of isolated organisms and"nits characteristics is significantly important due to the severe septicemia and high mortalities in this outbreak and its public"nhealth threats. Environmental contamination within the cages, and food contaminated with stools of other canaries were the"nsources of infection. Inspection for food hygiene, daily cleaning of canary’s cage from stool and carrier insects and rodents are"nnecessary to prevent such outbreaks. Combination of R-typing, RAPD-PCR and PFGE increase the differentiation power of"nisolates, however, they showed clonality of S. Typhimurium involved in this outbreak.

  19. Worldwide patterns of bird colouration on islands.

    Science.gov (United States)

    Doutrelant, Claire; Paquet, Matthieu; Renoult, Julien P; Grégoire, Arnaud; Crochet, Pierre-André; Covas, Rita

    2016-05-01

    Island environments share distinctive characteristics that offer unique opportunities to investigate parallel evolution. Previous research has produced evidence of an island syndrome for morphological traits, life-history strategies and ecological niches, but little is known about the response to insularity of other important traits such as animal signals. Here, we tested whether birds' plumage colouration is part of the island syndrome. We analysed with spectrophotometry the colouration of 116 species endemic to islands and their 116 closest mainland relatives. We found a pattern of reduced brightness and colour intensity for both sexes on islands. In addition, we found a decrease in the number of colour patches on islands that, in males, was associated with a decrease in the number of same-family sympatric species. These results demonstrate a worldwide pattern of parallel colour changes on islands and suggest that a relaxation of selection on species recognition may be one of the mechanisms involved.

  20. Island Armor

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new law has been enacted to protect China’s islands from destruction After three rounds of deliberations that began in June 2009, the National People’s Congress (NPC) Standing Committee endorsed the Law of Sea

  1. Governance, corporate social responsibility and cooperation in sustainable tourist destinations: the case of the island of Fuerteventura

    Directory of Open Access Journals (Sweden)

    Olga González-Morales

    2016-11-01

    Full Text Available This paper reflects on governance, corporate social responsibility (CSR and public-private cooperation in sustainable tourist destinations. The empirical analysis focuses on the island of Fuerteventura (the Canary Islands, where a process of coordinated decision making has begun, as well as putting in place plans to modernize the destination. Those responsible for tourism hotel and non-hotel accommodation were surveyed to assess the importance given to CSR in their companies. In particular, CSR’s environmental dimension and its relation with the public sector and other socio-economic factors, bearing in mind that Fuerteventura is a tourist destination in a Biosphere Reserve.

  2. Studies of HVC Plasticity in Adult Canaries Reveal Social Effects and Sex Differences as Well as Limitations of Multiple Markers Available to Assess Adult Neurogenesis.

    Science.gov (United States)

    Shevchouk, Olesya T; Ball, Gregory F; Cornil, Charlotte A; Balthazart, Jacques

    2017-01-01

    In songbirds, neurogenesis in the song control nucleus HVC is sensitive to the hormonal and social environment but the dynamics of this process is difficult to assess with a single exogenous marker of new neurons. We simultaneously used three independent markers to investigate HVC neurogenesis in male and female canaries. Males were castrated, implanted with testosterone and housed either alone (M), with a female (M-F) or with another male (M-M) while females were implanted with 17β-estradiol and housed with a male (F-M). All subjects received injections of the two thymidine analogues, BrdU and of EdU, respectively 21 and 10 days before brain collection. Cells containing BrdU or EdU or expressing doublecortin (DCX), which labels newborn neurons, were quantified. Social context and sex differentially affected total BrdU+, EdU+, BrdU+EdU- and DCX+ populations. M-M males had a higher density of BrdU+ cells in the ventricular zone adjacent to HVC and of EdU+ in HVC than M-F males. M birds had a higher ratio of BrdU+EdU- to EdU+ cells than M-F subjects suggesting higher survival of newer neurons in the former group. Total number of HVC DCX+ cells was lower in M-F than in M-M males. Sex differences were also dependent of the type of marker used. Several technical limitations associated with the use of these multiple markers were also identified. These results indicate that proliferation, recruitment and survival of new neurons can be independently affected by environmental conditions and effects can only be fully discerned through the use of multiple neurogenesis markers.

  3. Studies of HVC Plasticity in Adult Canaries Reveal Social Effects and Sex Differences as Well as Limitations of Multiple Markers Available to Assess Adult Neurogenesis

    Science.gov (United States)

    Shevchouk, Olesya T.; Ball, Gregory F.; Cornil, Charlotte A.

    2017-01-01

    In songbirds, neurogenesis in the song control nucleus HVC is sensitive to the hormonal and social environment but the dynamics of this process is difficult to assess with a single exogenous marker of new neurons. We simultaneously used three independent markers to investigate HVC neurogenesis in male and female canaries. Males were castrated, implanted with testosterone and housed either alone (M), with a female (M-F) or with another male (M-M) while females were implanted with 17β-estradiol and housed with a male (F-M). All subjects received injections of the two thymidine analogues, BrdU and of EdU, respectively 21 and 10 days before brain collection. Cells containing BrdU or EdU or expressing doublecortin (DCX), which labels newborn neurons, were quantified. Social context and sex differentially affected total BrdU+, EdU+, BrdU+EdU- and DCX+ populations. M-M males had a higher density of BrdU+ cells in the ventricular zone adjacent to HVC and of EdU+ in HVC than M-F males. M birds had a higher ratio of BrdU+EdU- to EdU+ cells than M-F subjects suggesting higher survival of newer neurons in the former group. Total number of HVC DCX+ cells was lower in M-F than in M-M males. Sex differences were also dependent of the type of marker used. Several technical limitations associated with the use of these multiple markers were also identified. These results indicate that proliferation, recruitment and survival of new neurons can be independently affected by environmental conditions and effects can only be fully discerned through the use of multiple neurogenesis markers. PMID:28141859

  4. William Herschel Telescope site characterization using the MOAO pathfinder CANARY on-sky data

    CERN Document Server

    Martin, O A; Gendron, E; Rousset, G; Vidal, F; Morris, T J; Basden, A G; Myers, R M; Ono, Y H; Neichel, B; Fusco, T

    2016-01-01

    Canary is the Multi-Object Adaptive Optics (MOAO) pathfinder for the future MOAO-assisted Integral-Field Units (IFU) proposed for Extremely Large Telescopes (ELT). The MOAO concept relies on tomographically reconstructing the turbulence using multiple measurements along different lines of sight. Tomography requires the knowledge of the statistical turbulence parameters, commonly recovered from the system telemetry using a dedicated profiling technique. For demonstration purposes with the MOAO pathfinder Canary , this identification is performed thanks to the Learn & Apply (L&A) algorithm, that consists in model- fitting the covariance matrix of WFS measurements dependent on relevant parameters: $C_n^2(h)$ profile, outer scale profile and system mis-registration. We explore an upgrade of this algorithm, the Learn 3 Steps (L3S) approach, that allows one to dissociate the identification of the altitude layers from the ground in order to mitigate the lack of convergence of the required empirical covarianc...

  5. Comparing therapeutic efficacy between ivermectin, selamectin, and moxidectin in canaries during natural infection with Dermanyssus gallinae.

    Science.gov (United States)

    Todisco, Gianluca; Paoletti, Barbara; Giammarino, Angelo; Manera, Maurizio; Sparagano, Olivier A E; Iorio, Raffaella; Giannella, Benedetta; Robbe, Domenico

    2008-12-01

    The aim of this study was to compare the efficacy of three spot-on drugs on canaries during Dermanyssus gallinae natural infections and during the breeding season. Three groups of canary couples (seven couples each) were included: group A was treated with ivermectin, B with selamectin, and C with moxidectin. All the drugs were administered topically infrascapularly. The parasitic charge was estimated before the treatment (t(0)) and after 8 (t(1)), 16 (t(2)), 24 (t(3)), and 32 (t(4)) days following the initial treatment. No significant differences were detected among the three tested drugs for the five repeats for each of the four mite stages (egg, larva, nymphs, and fed and unfed adults). With regard to the decrease in the mean numbers of red mites, ivermectin and selamectin exerted their efficacy at t(2), contrary to moxidectin at t(3).

  6. Final two-stage MOAO on-sky demonstration with CANARY

    Science.gov (United States)

    Gendron, E.; Morris, T.; Basden, A.; Vidal, F.; Atkinson, D.; Bitenc, U.; Buey, T.; Chemla, F.; Cohen, M.; Dickson, C.; Dipper, N.; Feautrier, P.; Gach, J.-L.; Gratadour, D.; Henry, D.; Huet, J.-M.; Morel, C.; Morris, S.; Myers, R.; Osborn, J.; Perret, D.; Reeves, A.; Rousset, G.; Sevin, A.; Stadler, E.; Talbot, G.; Todd, S.; Younger, E.

    2016-07-01

    CANARY is an on-sky Laser Guide Star (LGS) tomographic AO demonstrator in operation at the 4.2m William Herschel Telescope (WHT) in La Palma. From the early demonstration of open-loop tomography on a single deformable mirror using natural guide stars in 2010, CANARY has been progressively upgraded each year to reach its final goal in July 2015. It is now a two-stage system that mimics the future E-ELT: a GLAO-driven woofer based on 4 laser guide stars delivers a ground-layer compensated field to a figure sensor locked tweeter DM, that achieves the final on-axis tomographic compensation. We present the overall system, the control strategy and an overview of its on-sky performance.

  7. Within-island differentiation and between-island homogeneity : Non-equilibrium population structure in the seaweed Cladophoropsis membranacea (Chlorophyta) in the Canary Islands

    NARCIS (Netherlands)

    van der Strate, HJ; van de Zande, L; Stam, WT; Haroun, RJ; Olsen, JL

    2003-01-01

    The seaweed Cladophoropsis membranacea forms extensive mats of coalesced thalli on coral reefs and along rocky coastlines throughout the tropics and subtropics. In a previous study on Gran Canaria, small-scale dispersal distances were found to be limited to <5 m and significant differentiation (F-ST

  8. PSF reconstruction validated using on-sky CANARY data in MOAO mode

    Science.gov (United States)

    Martin, O. A.; Correia, C. M.; Gendron, E.; Rousset, G.; Gratadour, D.; Vidal, F.; Morris, T. J.; Basden, A. G.; Myers, R. M.; Neichel, B.; Fusco, T.

    2016-07-01

    CANARY is an open-loop tomographic adaptive optics (AO) demonstrator that was designed for use at the 4.2m William Herschel Telescope (WHT) in La Palma. Gearing up to extensive statistical studies of high redshifted galaxies surveyed with Multi-Object Spectrographs (MOS), the demonstrator CANARY has been designed to tackle technical challenges related to open-loop Adaptive-Optics (AO) control with mixed Natural Guide Star (NGS) and Laser Guide Star (LGS) tomography. We have developed a Point Spread Function (PSF)-Reconstruction algorithm dedicated to MOAO systems using system telemetry to estimate the PSF potentially anywhere in the observed field, a prerequisite to deconvolve AO-corrected science observations in Integral Field Spectroscopy (IFS). Additionally the ability to accurately reconstruct the PSF is the materialization of the broad and fine-detailed understanding of the residual error contributors, both atmospheric and opto-mechanical. In this paper we compare the classical PSF-r approach from Véran (1) that we take as reference on-axis using the truth-sensor telemetry to one tailored to atmospheric tomography by handling the off-axis data only. We've post-processed over 450 on-sky CANARY data sets with which we observe 92% and 88% of correlation on respectively the reconstructed Strehl Ratio (SR)/Full Width at Half Maximum (FWHM) compared to the sky values. The reference method achieves 95% and 92.5% exploiting directly the measurements of the residual phase from the Canary Truth Sensor (TS).

  9. Dilute solution properties of canary seed (Phalaris canariensis) starch in comparison to wheat starch.

    Science.gov (United States)

    Irani, Mahdi; Razavi, Seyed M A; Abdel-Aal, El-Sayed M; Hucl, Pierre; Patterson, Carol Ann

    2016-06-01

    Dilute solution properties of an unknown starch are important to understand its performance and applications in food and non-food industries. In this paper, rheological and molecular properties (intrinsic viscosity, molecular weight, shape factor, voluminosity, conformation and coil overlap parameters) of the starches from two hairless canary seed varieties (CO5041 & CDC Maria) developed for food use were evaluated in the dilute regime (Starch dispersions in DMSO (0.5g/dl)) and compared with wheat starch (WS). The results showed that Higiro model is the best among five applied models for intrinsic viscosity determination of canary seed starch (CSS) and WS on the basis of coefficient of determination (R(2)) and root mean square error (RMSE). WS sample showed higher intrinsic viscosity value (1.670dl/g) in comparison to CSS samples (1.325-1.397dl/g). Berry number and the slope of master curve demonstrated that CSS and WS samples were in dilute domain without entanglement occurrence. The shape factor suggested spherical and ellipsoidal structure for CO5041 starch and ellipsoidal for CDC Maria starch and WS. The molecular weight, coil radius and coil volume of CSSs were smaller than WS. The behavior and molecular characterization of canary seed starch showed its unique properties compared with wheat starch.

  10. Long term effects of ash fertilization of reed canary grass; Laangtidseffekter av askgoedsling vid roerflensodling

    Energy Technology Data Exchange (ETDEWEB)

    Palmborg, Cecilia; Lindvall, Eva

    2011-03-15

    Reed canary grass (RCG) is a bio-energy crop with large potential. It is a 1.5 . 2.5 m tall grass that is harvested in spring when it is grown as a fuel. At spring harvest it yields 3 . 10 ton field dried material per ha and year. One disadvantage when reed canary grass is used as a fuel is the high ash content, 5-10 %. This means that large quantities of ash have to be deposited which is expensive, about 1000 SEK/ton. However, since reed canary grass ash contains reasonable amounts of plant nutrients like phosphorous (P), potassium (K) and magnesium (Mg) it could be recycled as fertilizer in agriculture. The ash can be used without any pretreatment since, in agriculture, plant availability is desirable. The aim of this project, was to evaluate a field experiment, where ash was used as a fertilizer in reed canary grass. The experiment was established at the SLU research station in Umea, Sweden in the spring 2002. Three different fertilizer treatments were applied: Treatment A was fertilized with an ash produced by combustion of RCG together with municipal wastes (paper, plastic, leather), treatment B, an ash from combustion of RCG, and for treatment C commercial fertilizers were used. In total, 100 kg ha-1 of nitrogen (N), 15 kg ha-1 of phosphorous (P) and 80 kg ha-1 of potassium (K), were applied each year in all treatments. The amount of ash in treatment A and B was calculated from the chemical analysis of the ashes to be equal to the required amount of P, while K and N were supplied also by commercial fertilizers. [Table 1. Composition of the ashes] Literature study: There is a lack of knowledge about fertilization with reed canary grass ash, since few experiments have been conducted. The composition of reed canary grass is dependent of harvest date and the soil substrate. The amount of ash and the amount of harmful substances such as potassium and chloride generally decreases over winter, giving an increased fuel quality from spring harvest compared to autumn

  11. Wave-front error breakdown in LGS MOAO validated on-sky by CANARY

    CERN Document Server

    Martin, O A; Rousset, G; Gratadour, D; Vidal, F; Morris, T J; Basden, A G; Myers, R M; Correia, C M; Henry, D

    2016-01-01

    CANARY is the multi-object adaptive optics (MOAO) on-sky pathfinder developed in the perspective of Multi-Object Spectrograph on Extremely Large Telescopes~(ELTs). In 2013, CANARY was operated on-sky at the William Herschel telescope~(WHT), using three off-axis natural guide stars~(NGS) and four off-axis Rayleigh laser guide stars~(LGS), in open-loop, with the on-axis compensated turbulence observed with a H-band imaging camera and a Truth wave-front sensor~(TS) for diagnostic purposes. Our purpose is to establish a reliable and accurate wave-front error breakdown for LGS MOAO. This will enable a comprehensive analysis of \\cana on-sky results and provide tools for validating simulations of MOAO systems for ELTs. To evaluate the MOAO performance, we compared the CANARY on-sky results running in MOAO, in Single Conjugated Adaptive Optics~(SCAO) and in Ground Layer Adaptive Optics~(GLAO) modes, over a large set of data acquired in 2013. We provide a statistical study of the seeing. We also evaluated the wave-fro...

  12. Cultivation trials with reed canary grass. Final report; Saekerstaellande av paagaaende roerflenfoersoek. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Landstroem, Staffan [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Agricultural Research for Northern Sweden

    2000-11-01

    This report presents results from cultivation trials all over Sweden with reed canary grass (Phalaris arundinacea) performed during 1990-1999. The work has focused on long-term use in the spring harvest system to show the sustainability in production. The trials, started 1990, clearly show that the spring harvest system is sustainable and gives high yields with good quality. Still after 8 years there is continuously high yield in the spring harvest system on soils suitable for reed canary grass, which are humus-rich sandy soils with good water supply. Chemical analyses of many years harvested crop have now verified that concentrations of undesired elements are low and have low variation between years. The important ash content differs considerably between different soil conditions. Sandy and humus-rich soils have a favourable low ash content, but clayey soils with low humus content give high ash content in the crop. Results from this project will now make it possible to do more accurate calculations of the production economy of reed canary grass.

  13. Les formations marines et continentales intervolcaniques des îles Canaries orientales (Grande Canarie. Fuerteventura et Lanzarote: Stratigraphie et signiflcation paleoclimatique.

    Directory of Open Access Journals (Sweden)

    Meco, J.

    1985-08-01

    Full Text Available More than 20 m. y. of continuous activity in the Canary Islands have brought about the fossilization of marine fauna and soils which prove the existence of alternating warm and numid conditions of guinean origen, and also of drier influences from the Sahara, connected with the arrival of cold waters from the Lusitanian Sea. The sea deposits of the lower Pleistocene with Strombus coronatus and those of the upper Pleistocene with Strombus bubonius, which are caracteristically warm and the deposits of middle and upper Pleistoeene and of the Holocene, with various species of Patella and caracteristically cold (Meco, 1977, have already been related to volcanic activities dated by K/Ar (Meco y Steams, 1981 and are new being related to rapid effects of soil formation, the result of evaporation an clayey neoformation of volcanic materials which are constantly being renoved. The fairly rapid fossilization caused by volcanic activity, eliminates some of the effects accumulated over a period of time on the paleosoils, The existence of Saharian quartz, a mineral not found in volcanic products, and the simultaneous existence of more distant matters on the evolution of soilformation, like crusts which contain gypsum or attapulgyte of desert origin and bauxites containing nickel and tale of tropical, humid origin (Pomel, 1985, all this permit to find coherents conclusions.

    Más de 20 m. a. de actividad volcánica continuada ha permitido en las Canarias la fosilización de faunas marinas y suelos que testimonian una alternancia de condiciones cálidas y húmedas, de origen guineano, y de influencias secas, saharianas, relacionadas con aportes de aguas frescas de procedencia lusitana. Los depósitos marinos del Plioceno inferior con Strombus coronatus y los del Pleistoceno superior con Strombus bubonius, que revelan un carácter cálido, y los depósitos del Pleistoceno medio y superior y del Holoceno, con varias

  14. Home range and habitat use of reintroduced Javan Deer in Panaitan Island, Ujung Kulon National Park

    Directory of Open Access Journals (Sweden)

    Pairah

    2015-09-01

    Full Text Available The Javan deer which inhabit Panaitan Island (± 175 Km2 were reintroduced from Peucang Island (± 4.5 Km2 during 1978–1982 (3 males: 13 females. The information of home range and habitat use of these animals were needed for wildlife habitat management especially in the small island habitat. We measured the home range size and habitat use of Javan deer in Peucang Island and Panaitan Island and compared them. The home range size was measured using Minimum Convex Polygon and then the polygon of home ranges were used to measure the habitat use. The results showed that in general the home range size in all age class of Javan deer between both islands did not differ significantly, only subadult males in Peucang Island which have a larger home range size than subadult males in Panaitan Island. Javan deer in Panaitan Island have found suitable conditions.

  15. The real-time control system for the CANARY multi-object adaptive optics on-sky demonstrator

    Science.gov (United States)

    Dipper, N. A.; Basden, A.; Looker, N. E.; Gendron, E.; Geng, D.; Gratadour, D.; Hubert, Z.; Vidal, F.; Myers, R. M.; Rousset, G.; Sevin, A.; Younger, E. J.

    2010-07-01

    CANARY is a Multi-Object Adaptive Optics (MOAO) system designed to demonstrate the AO aspects of proposed EELT instruments such as the multi-object spectrograph EAGLE. The first phase of Canary will be executed on the 4.2m William Herschel Telescope in 2010. We describe here the AO Real-time Control System (RTCS) for Canary. This is based on a distributed architecture of components interconnected by a fast serial fabric (sFPDP). The hardware used is a hybrid of FPGA and CPU technology. The middleware used for system data telemetry and control is based on CORBA and the publish/subscribe pattern. The system is designed to be easily modified and extended for the later, higher order, phases of CANARY. In order to provide the increase in computational power required in higher order systems, the current CPU technology can be readily replaced by acceleration hardware based on FPGA or GPU technologies. The Canary RTCS thus provides a test-bed for these new technologies that will be required for E-ELT instruments. These design concepts can be developed to provide an RTCS for E-ELT instruments and are in line with those under consideration by ESO for the E-ELT AO systems to which instruments such as EAGLE will be required to interface.

  16. Tsunami deposits at high altitudes on the flanks of volcanic islands

    Science.gov (United States)

    Paris, Raphael

    2016-04-01

    It is actually difficult to infer the mechanisms and dynamics of giant mass failures of oceanic shield volcanoes and to evaluate related tsunami hazards. Marine conglomerates and gravels found at unusually high elevations in Hawaii, Cape Verde, Mauritius and Canary Islands are often interpreted as being the result of tsunami waves generated by such massive flank failures. In the first part of this contribution, we document tsunami deposits (marine gravels with pumices) attached to the northwestern slopes of Tenerife, Canary Islands, at altitudes up to 132 m asl. Stratigraphy of the deposits and composition of the pumices allows identifying sources of the successive tsunamis and proposing a new scenario for the Icod flank failure and El Abrigo caldera-forming eruption ca. 170 ka. Then we propose a litterature review of tsunami deposits at high altitudes on the flanks of volcanic islands, and especially oceanic shield volcanoes. These deposits are discussed in terms of texture, structure, composition and particularly the juvenile volcanic material, and implications for better understanding the mechanisms controlling massive flank failures.

  17. Trace element concentrations in Raillietina micracantha in comparison to its definitive host, the feral pigeon Columba livia in Santa Cruz de Tenerife (Canary Archipelago, Spain).

    Science.gov (United States)

    Torres, Jordi; Foronda, Pilar; Eira, Catarina; Miquel, Jordi; Feliu, Carles

    2010-01-01

    The use of systems involving bird parasites as bioindicators of environmental pollution has been scarcely studied in comparison to other models involving fish and rodent parasites, which have been demonstrated as particularly adequate due to their bioaccumulation capacities. The present study evaluated the accumulation of nine trace elements in the cestode Raillietina micracantha and in its host Columba livia collected from the densely populated city of Santa Cruz de Tenerife (Canary Islands, Spain). Samples (kidney, liver, pectoral muscle, feathers, and R. micracantha) of 27 infected C. livia were selected for trace element analysis by inductively coupled plasma-mass spectrometry. Element levels in pigeon tissues revealed some degree of pollution in Santa Cruz de Tenerife, particularly by Pb and Zn. Pb and Mn mean concentrations were higher in R. micracantha than in the pigeon's soft tissues, with subsequent high bioaccumulation factors for Pb (kidney = 15.38, liver = 10.38, muscle = 79.83) and Mn (kidney = 6.81, liver = 7.52, muscle = 19.89, feathers = 6.11), among others. The negative relations detected for As concentrations between liver and R. micracantha emphasize a possible role of the cestode in As detoxification in host tissues. Considering the obtained bioaccumulation factors, the system R. micracantha/C. livia is proposed as another promising bioindicator system to evaluate environmental toxic element exposure, particularly Pb and Mn, in areas where pollution levels are still relatively low and where both common species are present.

  18. Male Infertility

    Science.gov (United States)

    ... the urethra. Chromosome defects. Inherited disorders such as Klinefelter's syndrome — in which a male is born with ... or major abdominal or pelvic surgery Having a history of undescended testicles Being born with a fertility ...

  19. Wave-front error breakdown in laser guide star multi-object adaptive optics validated on-sky by Canary

    Science.gov (United States)

    Martin, O. A.; Gendron, É.; Rousset, G.; Gratadour, D.; Vidal, F.; Morris, T. J.; Basden, A. G.; Myers, R. M.; Correia, C. M.; Henry, D.

    2017-01-01

    Context. Canary is the multi-object adaptive optics (MOAO) on-sky pathfinder developed in the perspective of multi-object spectrograph on extremely large telescopes (ELTs). In 2013, Canary was operated on-sky at the William Herschel telescope (WHT), using three off-axis natural guide stars (NGS) and four off-axis Rayleigh laser guide stars (LGS), in open-loop, with the on-axis compensated turbulence observed with a H-band imaging camera and a Truth wave-front sensor (TS) for diagnostic purposes. Aims: Our purpose is to establish a reliable and accurate wave-front error breakdown for LGS MOAO. This will enable a comprehensive analysis of Canary on-sky results and provide tools for validating simulations of MOAO systems for ELTs. Methods: To evaluate the MOAO performance, we compared the Canary on-sky results running in MOAO, in single conjugated adaptive optics (SCAO) and in ground layer adaptive optics (GLAO) modes, over a large set of data acquired in 2013. We provide a statistical study of the seeing. We also evaluated the wave-front error breakdown from both analytic computations, one based on a MOAO system modelling and the other on the measurements from the Canary TS. We have focussed especially on the tomographic error and we detail its vertical error decomposition. Results: We show that Canary obtained 30.1%, 21.4% and 17.1% H-band Strehl ratios in SCAO, MOAO and GLAO respectively, for median seeing conditions with 0.66'' of total seeing including 0.59'' at the ground. Moreover, we get 99% of correlation over 4500 samples, for any AO modes, between two analytic computations of residual phase variance. Based on these variances, we obtain a reasonable Strehl-ratio (SR) estimation when compared to the measured IR image SR. We evaluate the gain in compensation for the altitude turbulence brought by MOAO when compared to GLAO.

  20. Male sexuality.

    Science.gov (United States)

    Ginsberg, Terrie B

    2010-05-01

    It should be recognized that sexuality in the aging male is of such import that a complete sexual history must be performed. By taking a complete sexual history, facts can be obtained that will allow for appropriate focus relating to a holistic evaluation and will enable us to dispel antiquated sexual myths pertaining to the aging male. If initiated by the history taker, questions concerning sexuality may be discussed more comfortably by the patient. Erectile dysfunction, male sexual response cycle, testosterone, sexually transmitted diseases, human immunodeficiency virus, long-term illness, along with religion and culture are explored in this article with the aim of improving one's knowledge base, self reflection, and awareness of the importance of male sexuality. A complete understanding and appreciation of the aging male's medical history, surgical history, social history, and emotional history as well as his sexual, cultural, and religious concepts will allow the health care provider to better analyze information, and to recommend and provide appropriate advice and treatment to the aging male patient.

  1. William Herschel Telescope site characterization using the MOAO pathfinder CANARY on-sky data

    Science.gov (United States)

    Martin, O. A.; Correia, C. M.; Gendron, E.; Rousset, G.; Vidal, F.; Morris, T. J.; Basden, A. G.; Myers, R. M.; Ono, Y. H.; Neichel, B.; Fusco, T.

    2016-07-01

    CANARY is the Multi-Object Adaptive Optics (MOAO) pathfinder for the future MOAO-assisted Integral-Field Units (IFU) proposed for Extremely Large Telescopes (ELT). The MOAO concept relies on tomographically reconstructing the turbulence using multiple measurements along different lines of sight. Tomography requires the knowledge of the statistical turbulence parameters, commonly recovered from the system telemetry using a dedicated profiling technique. For demonstration purposes with the MOAO pathfinder CANARY, this identification is performed thanks to the Learn & Apply (L&A) algorithm, that consists in model-fitting the covariance matrix of WFS measurements dependant on relevant parameters: Cn2(h) profile, outer scale profile and system mis-registration. We explore an upgrade of this algorithm, the Learn 3 Steps (L3S) approach, that allows one to dissociate the identification of the altitude layers from the ground in order to mitigate the lack of convergence of the required empirical covariance matrices therefore reducing the required length of data time-series for reaching a given accuracy. For nominal observation conditions, the L3S can reach the same level of tomographic error in using five times less data frames than the L&A approach. The L3S technique has been applied over a large amount of CANARY data to characterize the turbulence above the William Herschel Telescope (WHT). These data have been acquired the 13th, 15th, 16th, 17th and 18th September 2013 and we find 0.67"/8.9m/3.07m.s-1 of total seeing/outer scale/wind-speed, with 0.552"/9.2m/2.89m.s-1 below 1.5 km and 0.263"/10.3m/5.22m.s-1 between 1.5 and 20 km. We have also determined the high altitude layers above 20 km, missed by the tomographic reconstruction on CANARY , have a median seeing of 0.187" and have occurred 16% of observation time.

  2. Beautiful hainan island

    Institute of Scientific and Technical Information of China (English)

    汪伦

    2002-01-01

    Hainan Island is the second largest island in China. It is situated on the Nanhai Sea(South China Sea) and faces Guangdong Province across Qiongzhou Strait (海峡).Hainan Province was established (建立)in 1988. It consists of Hainan Island, Xisha Islands, Zhongsha Islands, Nansha Islands and the vast sea areas around them.Its total area is 340,000 km2.

  3. Comparative Cytogenetics between Two Important Songbird, Models: The Zebra Finch and the Canary

    Science.gov (United States)

    dos Santos, Michelly da Silva; Kretschmer, Rafael; Frankl-Vilches, Carolina; Bakker, Antje; Gahr, Manfred; O´Brien, Patricia C. M.; Ferguson-Smith, Malcolm A.

    2017-01-01

    Songbird species (order Passeriformes, suborder Oscines) are important models in various experimental fields spanning behavioural genomics to neurobiology. Although the genomes of some songbird species were sequenced recently, the chromosomal organization of these species is mostly unknown. Here we focused on the two most studied songbird species in neuroscience, the zebra finch (Taeniopygia guttata) and the canary (Serinus canaria). In order to clarify these issues and also to integrate chromosome data with their assembled genomes, we used classical and molecular cytogenetics in both zebra finch and canary to define their chromosomal homology, localization of heterochromatic blocks and distribution of rDNA clusters. We confirmed the same diploid number (2n = 80) in both species, as previously reported. FISH experiments confirmed the occurrence of multiple paracentric and pericentric inversions previously found in other species of Passeriformes, providing a cytogenetic signature for this order, and corroborating data from in silico analyses. Additionally, compared to other Passeriformes, we detected differences in the zebra finch karyotype concerning the morphology of some chromosomes, in the distribution of 5S rDNA clusters, and an inversion in chromosome 1. PMID:28129381

  4. Comparative Cytogenetics between Two Important Songbird, Models: The Zebra Finch and the Canary.

    Science.gov (United States)

    Dos Santos, Michelly da Silva; Kretschmer, Rafael; Frankl-Vilches, Carolina; Bakker, Antje; Gahr, Manfred; O Brien, Patricia C M; Ferguson-Smith, Malcolm A; de Oliveira, Edivaldo H C

    2017-01-01

    Songbird species (order Passeriformes, suborder Oscines) are important models in various experimental fields spanning behavioural genomics to neurobiology. Although the genomes of some songbird species were sequenced recently, the chromosomal organization of these species is mostly unknown. Here we focused on the two most studied songbird species in neuroscience, the zebra finch (Taeniopygia guttata) and the canary (Serinus canaria). In order to clarify these issues and also to integrate chromosome data with their assembled genomes, we used classical and molecular cytogenetics in both zebra finch and canary to define their chromosomal homology, localization of heterochromatic blocks and distribution of rDNA clusters. We confirmed the same diploid number (2n = 80) in both species, as previously reported. FISH experiments confirmed the occurrence of multiple paracentric and pericentric inversions previously found in other species of Passeriformes, providing a cytogenetic signature for this order, and corroborating data from in silico analyses. Additionally, compared to other Passeriformes, we detected differences in the zebra finch karyotype concerning the morphology of some chromosomes, in the distribution of 5S rDNA clusters, and an inversion in chromosome 1.

  5. Exercise Tiger: assessing the BCM impact of the 2012 Olympics on Canary Wharf.

    Science.gov (United States)

    Evett, Jonathan

    2011-02-01

    In this paper, collective corporate resilience is studied to see how a culture of sharing information and planning may assist other business communities to prepare for future events. The London 2012 Summer Olympic Games will see huge opportunity for businesses in London, and across Europe, but not without cost. Canary Wharf lies in the heart of London's Docklands and less than three miles from the Olympic Park at Stratford. Purpose-built as a business district, it accommodates a working population of 95,000 people, is home to some of the world's leading brands and has a vibrant retail complex of over 200 shops, bars and restaurants. This business community is preparing for every aspect of the Olympics and, in particular, the disruption the Games will bring. As a private estate, the community resilience approach fostered here is both better defined and finite in terms of those it includes as a result. Preparing together with joint exercises, forums and open communications in a network of trusted partners is yielding collective benefits and lending a stronger voice in the call for more information from official agencies. This paper outlines the benefits of collective planning and reports on the success of Canary Wharf's annual estate-wide business continuity exercise - the first major collective Olympics planning exercise in London.

  6. Testing the AGN unification model in the infrared. First results with GTC/CanariCam

    Science.gov (United States)

    Ramos Almeida, C.

    2015-05-01

    The unified model for Active Galactic Nuclei (AGN) accounts for a variety of observational differences in terms of viewing geometry alone. However, from the fitting of high spatial resolution infrared (IR) data with clumpy torus models, it has been hinted that the immediate dusty surroundings of Type-1 and 2 Seyfert nuclei might be intrinsically different in terms of covering factor (torus width and number of clouds). Moreover, these torus covering factors also showed variations among objects belonging to the same type, in contradiction with simple unification. Interestingly, these intrinsic differences in Seyfert tori could explain, for example, the lack of broad optical lines in the polarized spectra of about half of the brightest Seyfert 2 galaxies. On the other hand, recent IR interferometry studies have revealed that, in at least four Seyfert galaxies, the mid-IR emission is elongated in the polar direction. These results are difficult to reconcile with unified models, which claim that the bulk of the mid-IR emission comes from the torus. In this invited contribution I summarize the latest results on high angular resolution IR studies of AGN, which constitute a crucial test for AGN unification. These results include those from the mid-infrared instrument CanariCam on the 10.4 m Gran Telescopio CANARIAS (GTC), which are starting to be published by the CanariCam AGN team, Los Piratas (https://sites.google.com/site/piratasrelatedpublications).

  7. Analysis of on-sky MOAO performance of CANARY using natural guide stars

    CERN Document Server

    Vidal, Fabrice; Rousset, Gerard; Morris, Tim; Basden, Alastair; Myers, Richard; Brangier, Matthieu; Chemla, Fanny; Dipper, Nigel; Gratadour, Damien; Henry, David; Hubert, Zoltan; Longmore, Andy; Martin, Olivier; Talbot, Gordon; Younger, Eddy

    2014-01-01

    The first on-sky results obtained by CANARY, the Multi-Object Adaptive Optics (MOAO) demonstrator, are analysed. The data were recorded at the William Herschel Telescope, at the end of September 2010. We describe the command and calibrations algorithms used during the run and present the observing conditions. The processed data are MOAO-loop engaged or disengaged slope buffers, comprising the synchronised measurements of the four Natural Guide Stars (NGS) wavefront sensors running in parallel, and near Infra-Red (IR) images. We describe the method we use to establish the error budget of CANARY. We are able to evaluate the to- mographic and the open loop errors, having median values around 216 nm and 110 nm respectively. In addition, we identify an unexpected residual quasi-static field aberration term of mean value 110 nm. We present the detailed error budget analysed for three sets of data for three different asterisms. We compare the experimental budgets with the numerically simulated ones and demonstrate a...

  8. Open-loop tomography with artificial neural networks on CANARY: on-sky results

    CERN Document Server

    Osborn, J; Guzman, D; Basden, A; Morris, T J; Gendron, E; Butterley, T; Myers, R M; Gueslaga, A; Lasheras, F S; Victoria, M G; Rodriguez, M L S; Gratadour, D; Rousset, G

    2014-01-01

    We present recent results from the initial testing of an Artificial Neural Network (ANN) based tomographic reconstructor Complex Atmospheric Reconstructor based on Machine lEarNing (CARMEN) on Canary, an Adaptive Optics demonstrator operated on the 4.2m William Herschel Telescope, La Palma. The reconstructor was compared with contemporaneous data using the Learn and Apply (L&A) tomographic reconstructor. We find that the fully optimised L&A tomographic reconstructor outperforms CARMEN by approximately 5% in Strehl ratio or 15nm rms in wavefront error. We also present results for Canary in Ground Layer Adaptive Optics mode to show that the reconstructors are tomographic. The results are comparable and this small deficit is attributed to limitations in the training data used to build the ANN. Laboratory bench tests show that the ANN can out perform L&A under certain conditions, e.g. if the higher layer of a model two layer atmosphere was to change in altitude by ~300~m (equivalent to a shift of appr...

  9. PSF reconstruction validated using on-sky CANARY data in MOAO mode

    CERN Document Server

    Martin, O A; Gendron, E; Rousset, G; Gratadour, D; Vidal, F; Morris, T J; Basden, A G; Myers, R M; Neichel, B; Fusco, T

    2016-01-01

    In preparation of future Multi-Object Spectrographs (MOS) whose one of the major role is to provide an extensive statistical studies of high redshifted galaxies surveyed, the demonstrator Canary has been designed to tackle technical challenges related to open-loop Adaptive-Optics (AO) control with jointed Natural Guide Star (NGS) and Laser Guide Star (LGS) tomography. We have developed a Point Spread Function (PSF)-Reconstruction algorithm dedicated to MOAO systems using system telemetry to estimate the PSF potentially anywhere in the observed field, a prerequisite to post- process AO-corrected observations in Integral Field Spectroscopy (IFS). In this paper we show how to handle off-axis data to estimate the PSF using atmospheric tomography and compare it to a classical approach that uses on-axis residual phase from a truth sensor observing a natural bright source. We have reconstructed over 450 on-sky Canary PSFs and we get bias/1-${\\sigma}$ standard-deviation (std) of 1.3/4.8 on the H-band Strehl ratio (SR...

  10. An examination of amphibian sensitivity to environmental contaminants: are amphibians poor canaries?

    Science.gov (United States)

    Kerby, Jacob L; Richards-Hrdlicka, Kathryn L; Storfer, Andrew; Skelly, David K

    2010-01-01

    Nearly two decades ago, the global biodiversity crisis was catapulted to the front pages of newspapers with the recognition of worldwide amphibian declines. Amphibians earned their appellation, 'canaries in a coal mine', because of apparent high sensitivity to human-mediated environmental change. The most frequently cited causes for high susceptibility include permeable skin, a dual aquatic-terrestrial life cycle and a relatively rudimentary immune system. While some researchers have questioned the basis for the canary assertion, there has been no systematic evaluation of amphibian sensitivity to environmental challenges relative to other taxa. Here, we apply a database representing thousands of toxicity tests to compare the responses of amphibians relative to that of other taxonomic groups. The use of standardized methods combined with large numbers of identical challenges enables a particularly powerful test of relative effect size. Overall, we found that amphibians only exhibit moderate relative responses to water-borne toxins. Our findings imply that, as far as chemical contaminants are concerned, amphibians are not particularly sensitive and might more aptly be described as 'miners in a coal mine'. To the extent that amphibian declines have been mediated by chemical contaminants, our findings suggest that population losses and extinctions may have already occurred in a variety of taxa much more sensitive than amphibians.

  11. Fungal diversity in the rhizosphere of endemic plant species of Tenerife (Canary Islands): relationship to vegetation zones and environmental factors

    DEFF Research Database (Denmark)

    Zachow, Christin; Berg, Christian; Müller, Henry

    2008-01-01

    , molecular analysis of fungal communities was determined by single-strand conformation polymorphism (SSCP) analysis using universal and specific primers for Trichoderma. The highly diverse fungal communities were mainly characterized by ectomycorrhiza-forming Basidiomycota and a high proportion of yet...

  12. Radioactive contents in water Galleries Tenerife, Canary Islands; Contenido radioactivo en aguas de galerias de Tenerife, Islas Canarias

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Perez, M.; Duarte Rodriguez, X.; Triguero Perez, M.; Hernandez Armas, J.; Catalan Acosta, A.

    2011-07-01

    Water consumption by humans leads to the possible incorporation into the body of existing radionuclides in it and can cause undesirable effects on human health. To avoid or reduce them, various agencies have established limits for the concentration of radioactive substances in the water so that it can be used for human consumption. (Author)

  13. Oxygen isotope fractionation between bird eggshell calcite and body water: application to fossil eggs from Lanzarote (Canary Islands).

    Science.gov (United States)

    Lazzerini, Nicolas; Lécuyer, Christophe; Amiot, Romain; Angst, Delphine; Buffetaut, Eric; Fourel, François; Daux, Valérie; Betancort, Juan Francisco; Flandrois, Jean-Pierre; Marco, Antonio Sánchez; Lomoschitz, Alejandro

    2016-10-01

    Oxygen and carbon isotope compositions of fossil bird eggshell calcite (δ(18)Ocalc and δ(13)Ccalc) are regularly used to reconstruct paleoenvironmental conditions. However, the interpretation of δ(18)Ocalc values of fossil eggshells has been limited to qualitative variations in local climatic conditions as oxygen isotope fractionations between calcite, body fluids, and drinking water have not been determined yet. For this purpose, eggshell, albumen water, and drinking water of extant birds have been analyzed for their oxygen and carbon isotope compositions. Relative enrichments in (18)O relative to (16)O between body fluids and drinking water of +1.6 ± 0.9 ‰ for semi-aquatic birds and of +4.4 ± 1.9 ‰ for terrestrial birds are observed. Surprisingly, no significant dependence to body temperature on the oxygen isotope fractionation between eggshell calcite and body fluids is observed, suggesting that bird eggshells precipitate out of equilibrium. Two empirical equations relating the δ(18)Ocalc value of eggshell calcite to the δ(18)Ow value of ingested water have been established for terrestrial and semi-aquatic birds. These equations have been applied to fossil eggshells from Lanzarote in order to infer the ecologies of the Pleistocene marine bird Puffinus sp. and of the enigmatic giant birds from the Pliocene. Both δ(13)Ccalc and δ(18)Ocalc values of Puffinus eggshells point to a semi-aquatic marine bird ingesting mostly seawater, whereas low δ(13)Ccalc and high δ(18)Ocalc values of eggshells from the Pliocene giant bird suggest a terrestrial lifestyle. This set of equations can help to quantitatively estimate the origin of waters ingested by extinct birds as well as to infer either local environmental or climatic conditions.

  14. Cheetahs of the deep sea: deep foraging sprints in short-finned pilot whales off Tenerife (Canary Islands).

    Science.gov (United States)

    Aguilar Soto, Natacha; Johnson, Mark P; Madsen, Peter T; Díaz, Francisca; Domínguez, Iván; Brito, Alberto; Tyack, Peter

    2008-09-01

    1. Empirical testing of optimal foraging models for breath-hold divers has been difficult. Here we report data from sound and movement recording DTags placed on 23 short-finned pilot whales off Tenerife to study the foraging strategies used to catch deep-water prey. 2. Day and night foraging dives had a maximum depth and duration of 1018 m and 21 min. Vocal behaviour during dives was consistent with biosonar-based foraging, with long series of echolocation clicks interspersed with buzzes. Similar buzzes have been associated with prey capture attempts in other echolocating species. 3. Foraging dives seemed to adapt to circadian rhythms. Deep dives during the day were deeper, but contained fewer buzzes (median 1), than night-time deep dives (median 5 buzzes). 4. In most deep (540-1019 m) daytime dives with buzzes, a downward directed sprint reaching up to 9 m s(-1) occurred just prior to a buzz and coincided with the deepest point in the dive, suggestive of a chase after escaping prey. 5. A large percentage (10-36%) of the drag-related locomotion cost of these dives (15 min long) is spent in sprinting (19-79 s). This energetic foraging tactic focused on a single or few prey items has not been observed previously in deep-diving mammals but resembles the high-risk/high-gain strategy of some terrestrial hunters such as cheetahs. 6. Deep sprints contrast with the expectation that deep-diving mammals will swim at moderate speeds optimized to reduce oxygen consumption and maximize foraging time at depth. Pilot whales may have developed this tactic to target a deep-water niche formed by large/calorific/fast moving prey such as giant squid.

  15. Frugivory and factors influencing visitation by birds at "Balo" (Plocama pendula Ait., Rubiaceae) plants in the Canary Islands

    OpenAIRE

    Nogales, Manuel; Valido, Alfredo; Medina, Félix M.; Delgado, Juan D.

    1999-01-01

    Studies dealing with interactions between vertebrate frugivores and fleshy-fruited plants have focused on the selective role of vertebrates upon fruit or plant traits (l.e., dispersal syndromes), assuming that these systems are coevolved (Howe & Estabrook. 1977. Herrera. 1981).

  16. Animals and ritual. Faunal remains from sacrificial altars of El Alto de Garajonay (La Gomera, Canary Islands, Spain

    Directory of Open Access Journals (Sweden)

    Verónica ALBERTO BARROSO

    2015-11-01

    Full Text Available This paper addresses the meaning of animals in the sanctuary of Garajonay, in La Gomera. It is a main sacred place for the Prehispanic population, in which they systematically used to perform ritual celebrations within the time period between ss. vii-xii ad cal. These activities took place in the sacrificial altars where various products, essential for the survival of the ancient inhabitants, were burned. For this purpose faunal repertoires have been studied, establishing their composition and processing patterns. It is concluded a standardized behavior defined by the sacrifice of domestic animals, with a rigid selection of skeletal parts actives in the ritual. In that process the fire plays a key role, contributing to the consecration of certain social practices. It has also been analyzed the meaning of such practices in the ideological framework of those populations.

  17. A competitive study of two tourism destinations through the application of conjoint analysis techniques: the case of the Canary Islands

    Directory of Open Access Journals (Sweden)

    Parra López, Eduardo

    2004-01-01

    Full Text Available The aspiration to know and to correspond to consumer expectations, supposes a continuous challenge that companies must confront and has become a central issue in an extant literature. There is ample agreement about the importance of consumer orientation for the competitiveness of companies. Businesses are faced with the need to satisfy customers today and to develop new products for the future. These requirements are accentuated in the tour-ist sector because they have a particular dependence on "tourist preferences". The aim of this paper is to contribute to this debate with the results of an analysis that seeks to deepen the knowledge of competitive advantages in the hotel sector of two tourism destinations by studying the utility that the different products offered provides to de-mand. By means of the application of the statistical techniques of conjoint analysis and simulation, we have obtained a model to apply to entrepreneurial decision-making that enables us to recognise the product that, among those supplied, most value provides to the demand of each tourism destination, as well as the observation of significant differences between those destinations

  18. Acoustical detection of early instar Rhynchophorus ferrugineus (Coleoptera: Curculionidae) in Canary Island date palm Phoenix canariensis (Arecales: Arecaceae)

    Science.gov (United States)

    The red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier), is of international concern due to destructive larval feeding within palm trees. Originating from tropical Asia, RPW has spread throughout the eastern hemisphere where it has become a significant economic pest to the ornamental and date...

  19. Identification, antimicrobial susceptibility, and virulence factors of Enterococcus spp. strains isolated from Camels in Canary Islands, Spain.

    Science.gov (United States)

    Tejedor Junco, María Teresa; Gonzalez-Martin, Margarita; Rodriguez Gonzalez, Noe Francisco; Gutierrez, Carlos

    2015-01-01

    This study investigated the presence of Enterococcus spp. strains in camel faeces, their virulence factors, and resistance to the antibiotics commonly used as therapy of enterococcal infections. One hundred and seventy three Enterococcus strains were isolated and identified to species level using polymerase chain reaction (PCR). Susceptibility to 11 antimicrobials was determined by disk diffusion method. Minimal Inhibitory Concentrations (MIC) of penicillin, ampicillin, vancomycin, teicoplanin, gentamicin, and streptomycin were all determined. Genes encoding resistance to vancomycin, tetracycline, and erythromycin as well as genes encoding some virulence factors were identified by PCR. Enterococcus hirae (54.3%) and Enterococcus faecium (25.4%) were the species most frequently isolated. None of the strains were resistant to vancomycin, teicoplanin, ampicillin or showed high level aminoglycoside resistance (HLAR). Strains resistant to rifampicin (42.42%) were those most commonly found followed those resistant to trimethoprim - sulfamethoxazole (33.33%). The genes tetM, tetL, vanC1, and vanC2-C3 were detected in some strains. Virulence genes were not detected. Monitoring the presence of resistant strains of faecal enterococci in animal used with recreational purposes is important to prevent transmission of those strains to humans and to detect resistance or virulence genes that could be transferred to other clinically important bacteria.

  20. Chabazite and dolomite formation in a dolocrete profile: An example of a complex alkaline paragenesis in Lanzarote, Canary Islands

    Science.gov (United States)

    Alonso-Zarza, Ana M.; Bustamante, Leticia; Huerta, Pedro; Rodríguez-Berriguete, Álvaro; Huertas, María José

    2016-05-01

    This paper studies the weathering and soil formation processes operating on detrital sediments containing alkaline volcanic rock fragments of the Mirador del Río dolocrete profile. The profile consists of a lower horizon of removilised weathered basalts, an intermediate red sandy mudstones horizon with irregular carbonate layers and a topmost horizon of amalgamated carbonate layers with root traces. Formation occurred in arid to semiarid climates, giving place to a complex mineralogical association, including Mg-carbonates and chabazite, rarely described in cal/dolocretes profiles. Initial vadose weathering processes occurred in the basalts and in directly overlying detrital sediments, producing (Stage 1) red-smectites and dolomicrite. Dominant phreatic (Stage 2) conditions allowed precipitation of coarse-zoned dolomite and chabazite filling porosities. In Stages 3 and 4, mostly pedogenic, biogenic processes played an important role in dolomite and calcite accumulation in the profile. Overall evolution of the profile and its mineralogical association involved initial processes dominated by alteration of host rock, to provide silica and Mg-rich alkaline waters, suitable for chabazite and dolomite formation, without a previous carbonate phase. Dolomite formed both abiogenically and biogenically, but without a previous carbonate precursor and in the absence of evaporites. Dominance of calcite towards the profile top is the result of Mg/Ca decrease in the interstitial meteoric waters due to decreased supply of Mg from weathering, and increased supply of Ca in aeolian dust. Meteoric origin of the water is confirmed by C and O isotope values, which also indicate lack of deep sourced CO2. The dolocrete studied and its complex mineral association reveal the complex interactions that occur at surface during weathering and pedogenesis of basalt-sourced rocks.

  1. The arrival of the offset printing system to the press in the Canary Islands: implications in the image treatment

    OpenAIRE

    Alberto Ardèvol Abreu

    2011-01-01

    El presente artículo forma parte de un trabajo de investigación más extenso sobre la evolución de la fotografía de prensa en Canarias desde el período 1975-1980 hasta la primera década del siglo XXI. Durante la segunda mitad de la década de 1970 se produjo en el archipiélago, de manera paulatina, la transición del sistema de impresión tipográfica al sistema offset. A través de estas páginas pretendemos analizar la influencia que tuvo en la fotografía de prensa de las islas la llegada de este ...

  2. A competitive study of two tourism destinations through the application of conjoint analysis techniques: the case of the Canary Islands

    Directory of Open Access Journals (Sweden)

    Eduardo Parra López

    2004-01-01

    Full Text Available La aspiración de conocer y corresponder las expectativas de los consumidores, supone un continuo objetivo en la gran mayoría de las empresas, así como un tema central de análisis y debate a lo largo y ancho de la literatura. Existe un amplio consenso sobre la importancia que la orientación al cliente tiene para la competitividad de las empresas actuales. Este hecho se acentúa aún más si cabe en las empresas del sector turístico. En este trabajo tratamos de profundizar en el conocimiento de las ventajas competitivas del sector hotelero de dos destinos turísticos a través del estudio de la utilidad que aportan a la demanda los diferentes productos ofertados. Mediante la aplicación de técnicas estadísticas de análisis conjunto y de simulación hemos obtenidos un modelo de aplicación en la toma de decisiones empresariales, y que permite reconocer no sólo el producto que, entre los ofertados, mayor valor aporta a la demanda de cada destino turístico sino la existencia de diferencias significativas entre destinos

  3. Oxygen isotope fractionation between bird eggshell calcite and body water: application to fossil eggs from Lanzarote (Canary Islands)

    Science.gov (United States)

    Lazzerini, Nicolas; Lécuyer, Christophe; Amiot, Romain; Angst, Delphine; Buffetaut, Eric; Fourel, François; Daux, Valérie; Betancort, Juan Francisco; Flandrois, Jean-Pierre; Marco, Antonio Sánchez; Lomoschitz, Alejandro

    2016-10-01

    Oxygen and carbon isotope compositions of fossil bird eggshell calcite (δ18Ocalc and δ13Ccalc) are regularly used to reconstruct paleoenvironmental conditions. However, the interpretation of δ18Ocalc values of fossil eggshells has been limited to qualitative variations in local climatic conditions as oxygen isotope fractionations between calcite, body fluids, and drinking water have not been determined yet. For this purpose, eggshell, albumen water, and drinking water of extant birds have been analyzed for their oxygen and carbon isotope compositions. Relative enrichments in 18O relative to 16O between body fluids and drinking water of +1.6 ± 0.9 ‰ for semi-aquatic birds and of +4.4 ± 1.9 ‰ for terrestrial birds are observed. Surprisingly, no significant dependence to body temperature on the oxygen isotope fractionation between eggshell calcite and body fluids is observed, suggesting that bird eggshells precipitate out of equilibrium. Two empirical equations relating the δ18Ocalc value of eggshell calcite to the δ18Ow value of ingested water have been established for terrestrial and semi-aquatic birds. These equations have been applied to fossil eggshells from Lanzarote in order to infer the ecologies of the Pleistocene marine bird Puffinus sp. and of the enigmatic giant birds from the Pliocene. Both δ13Ccalc and δ18Ocalc values of Puffinus eggshells point to a semi-aquatic marine bird ingesting mostly seawater, whereas low δ13Ccalc and high δ18Ocalc values of eggshells from the Pliocene giant bird suggest a terrestrial lifestyle. This set of equations can help to quantitatively estimate the origin of waters ingested by extinct birds as well as to infer either local environmental or climatic conditions.

  4. Groundwater salinity and hydrochemical processes in the volcano-sedimentary aquifer of La Aldea, Gran Canaria, Canary Islands, Spain.

    Science.gov (United States)

    Cruz-Fuentes, Tatiana; Cabrera, María del Carmen; Heredia, Javier; Custodio, Emilio

    2014-06-15

    The origin of the groundwater salinity and hydrochemical conditions of a 44km(2) volcano-sedimentary aquifer in the semi-arid to arid La Aldea Valley (western Gran Canaria, Spain) has been studied, using major physical and chemical components. Current aquifer recharge is mainly the result of irrigation return flows and secondarily that of rainfall infiltration. Graphical, multivariate statistical and modeling tools have been applied in order to improve the hydrogeological conceptual model and identify the natural and anthropogenic factors controlling groundwater salinity. Groundwater ranges from Na-Cl-HCO3 type for moderate salinity water to Na-Mg-Cl-SO4 type for high salinity water. This is mainly the result of atmospheric airborne salt deposition; silicate weathering, and recharge incorporating irrigation return flows. High evapotranspiration produces significant evapo-concentration leading to relative high groundwater salinity in the area. Under average conditions, about 70% of the water used for intensive agricultural exploitation in the valley comes from three low salinity water runoff storage reservoirs upstream, out of the area, while the remaining 30% derives from groundwater. The main alluvial aquifer behaves as a short turnover time reservoir that adds to the surface waters to complement irrigation water supply in dry periods, when it reaches 70% of irrigation water requirements. The high seasonality and intra-annual variability of water demand for irrigation press on decision making on aquifer use by a large number of aquifer users acting on their own.

  5. Chemical composition and methane yield of reed canary grass as influenced by harvesting time and harvest frequency

    DEFF Research Database (Denmark)

    Kandel, Tanka Prasad; Sutaryo, Sutaryo; Møller, Henrik Bjarne;

    2013-01-01

    This study examined the influence of harvest time on biomass yield, dry matter partitioning, biochemical composition and biological methane potential of reed canary grass harvested twice a month in one-cut (OC) management. The regrowth of biomass harvested in summer was also harvested in autumn a...

  6. Climate vs. topography – spatial patterns of plant species diversity and endemism on a high-elevation island

    DEFF Research Database (Denmark)

    Irl, Severin David Howard; Harter, David E. V.; Steinbauer, Manuel;

    2015-01-01

    variables (esp. elevation/temperature and rainfall seasonality) explain endemicity. Spatial patterns of species richness, endemic richness and endemicity were in part geographically decoupled from each other. Synthesis. We identified several topography-dependent processes ranging from evolutionary processes......Climate and topography are among the most fundamental drivers of plant diversity. Here, we assessed the importance of climate and topography in explaining diversity patterns of species richness, endemic richness and endemicity on the landscape scale of an oceanic island and evaluated...... the independent contribution of climatic and topographic variables to spatial diversity patterns. We constructed a presence/absence matrix of perennial endemic and native vascular plant species (including subspecies) in 890 plots on the environmentally very heterogeneous island of La Palma, Canary Islands...

  7. Drug utilization by children in Tenerife Island.

    Science.gov (United States)

    Sanz, E J; Boada, J N

    1988-01-01

    Drug utilization was studied in children below 14 years of age in Tenerife, Canary Islands, who were seen as outpatients by 15 paediatricians and 10 general practitioners. Data on diagnosis, previous drug exposure and prescriptions were collected from a random sample of 1327 children. Nose and throat infections (40.1%), respiratory diseases (10.2%) and miscellaneous symptoms, namely common cold, influenza or nasal congestion (10.5%), were the most frequent reasons for visiting a physician. Antibiotics represented 28.5% of the prescriptions. The youngest group (0-2 years) received more drugs than the other two groups (2-6 and 6-14 years), and 8.4% of the children did not receive any drug. Only 358 (5.1%) of the 7,000 pharmaceutical specialities available were used, and the 10 most frequently prescribed drug products constituted more than 30% of all prescriptions. Combination drugs accounted for 42.4% of the prescribed items. Healthy children presenting only for check up were frequently treated with drugs.

  8. Reconstructing Holocene vegetation on the island of Gran Canaria before and after human colonization

    DEFF Research Database (Denmark)

    de Nascimento, Lea; Nogué, Sandra; Criado, Constantino;

    2016-01-01

    We provide the first fossil pollen and charcoal analysis from the island of Gran Canaria (Canary Islands). The pollen record obtained from Laguna de Valleseco (870 m a.s.l.) spans the late Holocene (c. 4500–1500 cal. yr BP) and thereby captures the impact of human colonization. During the earlies...... cal. yr BP. The next shift in vegetation (c. 1600 cal. yr BP) involved the decrease of grasses in favour of shrubs and trees like Morella faya, suggesting that agriculture was abandoned at the site....... period, pollen composition resembled contemporary thermophilous communities, with palms (Phoenix canariensis) and junipers (Juniperus cf. turbinata) being the dominant trees, suggesting that these elements were more widespread in the past. Vegetation in Valleseco began to change at around 2300 cal. yr BP...

  9. Analysis of glabrous canary seeds by ELISA, mass spectrometry, and Western blotting for the absence of cross-reactivity with major plant food allergens.

    Science.gov (United States)

    Boye, Joyce Irene; Achouri, Allaoua; Raymond, Nancy; Cleroux, Chantal; Weber, Dorcas; Koerner, Terence B; Hucl, Pierre; Patterson, Carol Ann

    2013-06-26

    Glabrous (hairless) canary seed belongs to the Poaceae (Gramineae) family and could serve as an alternative source of gluten-free cereal grain. In this study, allergenic cross-reactivities between hairless, dehulled canary seeds (Phalaris canariensis) and major allergenic proteins from gluten, soy, peanuts, tree nuts, sesame, and mustard were studied using commercial enzyme-linked immune sorbent assay (ELISA) kits specific for these target allergens. Mass spectrometry (MS) and immunoblotting were further used to assess for the presence of gluten-specific protein fragments. MS results revealed the likely presence of proteins homologous with rice, oat, corn, carrot, tomato, radish, beet, and chickpea. However, no presence of celiac-related gluten fragments from wheat, rye, barley, or their derivatives was found. Immunoblotting studies yielded negative results, further confirming the absence of gluten in the canary seed samples tested. No cross-reactivities were detected between canary seeds and almond, hazelnut, mustard, peanut, sesame, soy, walnut, and gluten using ELISA.

  10. Escaping Devil's Island: Confronting Racism, Learning History

    Science.gov (United States)

    Grant, Carl A.

    2011-01-01

    This article argues that African Americans, especially males living in urban areas, are physically and mentally trapped on a Devil's Island. The penal colony on the coast of French Guiana is a metaphor for the boundaries and constraints that close off opportunities and constrain African American historical knowledge. The article argues that…

  11. Crustal deformation study in the Canary Archipelago by the analysis of GPS observations

    Science.gov (United States)

    Martín, Adriana; Sevilla, Miguel; Zurutuza, Joaquín

    2014-06-01

    The Canary Archipelago is an active volcanic region located in the African plate, at 100 Km of the northwest coast of Africa. The Complutense University of Madrid, Institute of Astronomy and Geodesy (CSIC-UCM) and University of Jaén, established a GPS Network in this region and carried out six observations campaigns from 2002 to 2009. The focus of thiswork is processing and analyzing these observations to study the geodynamic behavior of the stations of this network. The data have been computed with the Bernese GPS Software Version 5.0 obtaining individual solutions of coordinates for each session and campaign, the coordinate velocities of the stations and the time series of baselines formed between them. Results show consistency of station velocities compared to behaviour of areas permanent stations and baselines stability. No deformations could be detected.

  12. A customizable 3-dimensional digital atlas of the canary brain in multiple modalities

    DEFF Research Database (Denmark)

    Vellema, Michiel; Verschueren, Jacob; Van Meir, Vincent

    2011-01-01

    the number of detectable brain regions, including most of the areas involved in song perception, learning, and production. The brain atlas can readily be used to determine the stereotactic location of delineated brain areas at any desirable head angle. Alternatively the brain data can be used to determine...... throughout their lives. This trait makes this bird species particularly valuable to study the functional relationship between the continued plasticity in the singing behavior and alterations in the anatomy and physiology of the brain. In order to optimally interpret these types of studies, a detailed...... understanding of the brain anatomy is essential. Because traditional 2-dimensional brain atlases are limited in the information they can provide about the anatomy of the brain, here we present a 3-dimensional MRI-based atlas of the canary brain. Using multiple imaging protocols we were able to maximize...

  13. Evaluating the predictive value of doublecortin as a marker for adult neurogenesis in canaries (Serinus canaria)

    DEFF Research Database (Denmark)

    Vellema, Michiel; Hertel, Moritz; Urbanus, Susan L

    2014-01-01

    as a popular indirect tool to monitor adult neurogenesis in a variety of species. However, little is known about its possible involvement in other cellular processes and a thorough validation of DCX as a quantitative measure for neurogenesis is generally lacking. Here we investigated the relationship between...... DCX expression and neuron recruitment in the brains of adult canaries (Serinus canaria), a species well-known for its adult neurogenesis. We examined the age and functional state of DCX-labeled cells by using mitotic and neuron-specific markers, retrograde tracings, and immediate early gene...... colocalizations. Although DCX expression was high in brain areas implicated in adult neurogenesis, DCX-expressing neurons were also abundant in regions that do not recruit new neurons. Moreover, DCX expression was observed in adult, active neurons, differentiated projection neurons, and birth-dated neurons of up...

  14. Canary literature and culture in the reign of Carlos IV (1788-1808

    Directory of Open Access Journals (Sweden)

    Victoria GALVÁN GONZÁLEZ

    2012-02-01

    Full Text Available This work wants to offer a short view of the literature and culture developed in the Canary Isles during the reign period of Charles IV, from a general point of view. Therefore, I cannot offer a detailed perspective of each of the aspects dealt with. This way, what is tackled in this work is a revision of the socio-cultural activities connected to the gatherings or to the economic societies, the educative circumstances, the activity developed by the bishops with the carrying out of facilities or with a reforming teaching at the reading level, such as Tavira, the production of books with an allusion to the printing activity, the most developed literary genres and their authors, the topic preference in poetry —majority genre—, in prose and in theatre, and an allusion to some of the private libraries.

  15. Comparison of biogas production from wild and cultivated varieties of reed canary grass.

    Science.gov (United States)

    Oleszek, Marta; Król, Aleksandra; Tys, Jerzy; Matyka, Mariusz; Kulik, Mariusz

    2014-03-01

    The chemical composition and efficiency of biogas production in the methane fermentation process of silages of wild and cultivated varieties of reed canary grass were compared. An attempt was made to answer the question on how the habitat and the way of utilization of plants affect chemical composition and biogas yield. Physicochemical properties such as dry matter, organic dry matter, protein, fat, crude fiber fraction, macro- and microelements content were considered. The anaerobic digestion process and FTIR analysis were also carried out. The results showed that the two varieties differ essentially in their physical and chemical properties. The cultivated variety was characterized by higher biogas yield (406Ndm(3)kg(-1) VS) than the wild one (120Ndm(3)kg(-1) VS). This was probably related to the chemical composition of plants, especially the high content of indigestible crude fiber fractions and ash. These components could reduce biogas quantity and quality.

  16. Seabird diversity hotspot linked to ocean productivity in the Canary Current Large Marine Ecosystem

    Science.gov (United States)

    Attrill, Martin J.; Becker, Peter H.; Egevang, Carsten; Furness, Robert W.; Grémillet, David; Kopp, Matthias; Lescroël, Amélie; Matthiopoulos, Jason; Peter, Hans-Ulrich; Phillips, Richard A.

    2016-01-01

    Upwelling regions are highly productive habitats targeted by wide-ranging marine predators and industrial fisheries. In this study, we track the migratory movements of eight seabird species from across the Atlantic; quantify overlap with the Canary Current Large Marine Ecosystem (CCLME) and determine the habitat characteristics that drive this association. Our results indicate the CCLME is a biodiversity hotspot for migratory seabirds; all tracked species and more than 70% of individuals used this upwelling region. Relative species richness peaked in areas where sea surface temperature averaged between 15 and 20°C, and correlated positively with chlorophyll a, revealing the optimum conditions driving bottom-up trophic effects for seabirds. Marine vertebrates are not confined by international boundaries, making conservation challenging. However, by linking diversity to ocean productivity, our research reveals the significance of the CCLME for seabird populations from across the Atlantic, making it a priority for conservation action. PMID:27531154

  17. Reed canary grass yield and fuel quality in Estonian farmers' fields

    Energy Technology Data Exchange (ETDEWEB)

    Heinsoo, Katrin; Hein, Katre; Melts, Indrek; Holm, Bert [Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Riia 181, 51014 Tartu (Estonia); Ivask, Mari [Tartu College, Tallinn University of Technology, Puiestee 78, 51008 Tartu (Estonia)

    2011-01-15

    Reed canary grass (Phalaris arundinacea) is one of the possible raw materials for bioenergy production in northern Europe. Its cultivation is favoured because its high productivity and local origin. However, problems with the biomass quality for combustion have been reported. Usually delayed harvest in spring is suggested to improve the quality and decrease the moisture content of biomass. On the other hand, the feasibility of spring harvest depends on local climatic conditions and may cause yield losses. In current paper we studied reed canary grass fields in Estonia locating on different soil types and cultivated with various varieties. The influence of several fertilisation schemes on biomass yield was analysed. Our results indicated that production was higher on mineral soils than on the organic soil of abandoned peat extraction sites. Even different types of fertilisation did not increase the production on organic soils to the level comparable to those on mineral soils. Among studied varieties 'Venture' had the highest production. The highest yield per area was obtained late in the autumn (12.7 t d.w. per ha and 7.2 t d.w. per ha on mineral and organic soils, respectively). By spring the amount of biomass had decreased in all studied sites. Due to wet soil some of the fields remained unharvested, the others had high yield losses during practical harvesting. The chemical analyses did not reveal significant differences in the composition of biomass between late autumn and spring. Therefore we conclude that late autumn harvest should be preferred in local climatic conditions. (author)

  18. Radioactive content in groundwater in the island of Tenerife (Canary Islands); Contenido radioactivo en aguas en aguas subterraneas de la Isla de Tenerifie (Canarias)

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Perez, M.; Duarte-Rodriguez, X.; Rodriguez-Perestelo, N.; Catalan-Acosta, A.; Fernandez- De Aldecoa, J. C.; Hernandez Armas, J.

    2013-07-01

    At present the groundwater in Tenerife is still the main resource to meet the demands of all kinds. Currently, due to the salt content, groundwater is treated using reversible electrodialysis desalination systems before drinking it. (Author)

  19. Accumulation of toxic metals (Pb and Cd) in the sea urchin Diadema aff. antillarum Philippi, 1845, in an oceanic island (Tenerife, Canary Islands).

    Science.gov (United States)

    Hernández, Ofelia Dolores; Gutiérrez, Angel José; González-Weller, Dailos; Lozano, Gonzalo; Melón, Enrique García; Rubio, Carmen; Hardisson, Arturo

    2010-06-01

    This document shows the results obtained from a study on the concentration of toxic heavy metals in the internal tissue and exoskeleton of sea urchins, collected from their natural habitat. The levels of lead and cadmium were measured by Graphite Furnace Atomic Absorption Spectrometry. The mean concentrations of lead and cadmium in the internal tissue were 304.04 and 260.54 microg/kg respectively, whereas in the shell they were 185.02 and 142.48 microg/kg. We also performed a statistical analysis of the differences in the distribution of metals between their exoskeleton and their internal content, a correlation study of the metal content in internal tissue and shell and sampling areas, and a correlation study between the metal content and sample size. Since the sea urchin Diadema antillarum presents a wide range of variation in metal content, this study suggests that this species is an excellent bioindicator of heavy metal contamination.

  20. Multi-levelling and externalizing migration and asylum: lessons from the southern European islands

    Directory of Open Access Journals (Sweden)

    Anna Triandafyllidou

    2014-05-01

    Full Text Available Southern European countries have come to constitute the most vulnerable external border of the European Union (EU over the last decade. Irregular migration pressures have been acutely felt on the EU’s southern sea borders, and particularly on four sets of islands: Canary Islands (Spain, Lampedusa and Linosa (Italy, Malta, and Aegean Islands (Greece. This quartet is, to a large extent, used as stepping stones by irregular migrants and asylum seekers to reach the European continent. This paper studies the role of these islands as ‘outposts’ of a framework of externalization. It starts by discussing the notion of externalization and its different facets. It considers how externalization is linked to both fencing and gate-keeping strategies of migration and asylum control. The second part of the paper focuses on the special role of the island quartet with respect to the externalization web cast by national and EU-wide migration policies. It concludes with a critical reflection on the multi-level character of externalization policies and practices that occur both within the EU and between the EU and third countries.

  1. Modelling the extreme precipitation event over Madeira Island on 20 February 2010

    Directory of Open Access Journals (Sweden)

    T. Luna

    2011-09-01

    Full Text Available In the morning of the 20 February of 2010 an extreme precipitation event occurred over Madeira Island. This event triggered several flash floods and mudslides in the southern parts of the island, resulting in 42 confirmed deaths, 100 injured, and at least 8 people still missing. These extreme weather conditions were associated to a weather frontal system moving northeastwards embedded in a low pressure area centered in the Azores archipelago. This storm was one in a series of such storms that affected Portugal, Spain, Morocco and the Canary islands causing flooding and strong winds. These storms were bolstered by an unusually strong sea surface temperature gradient across the Atlantic Ocean.

    In this study, the WRF model is used to evaluate the intensity and predictability of this precipitation extreme event over the island. The synoptic/orographic nature of the precipitation is also evaluated, as well as the sensitivity of the model to horizontal resolution and cumulus parameterization. Orography was found to be the main factor explaining the occurrence, amplitude and phase of precipitation over the Island.

  2. Geographical, temporal and environmental determinants of bryophyte species richness in the Macaronesian islands.

    Science.gov (United States)

    Aranda, Silvia C; Gabriel, Rosalina; Borges, Paulo A V; Santos, Ana M C; de Azevedo, Eduardo Brito; Patiño, Jairo; Hortal, Joaquín; Lobo, Jorge M

    2014-01-01

    Species richness on oceanic islands has been related to a series of ecological factors including island size and isolation (i.e. the Equilibrium Model of Island Biogeography, EMIB), habitat diversity, climate (i.e., temperature and precipitation) and more recently island ontogeny (i.e. the General Dynamic Model of oceanic island biogeography, GDM). Here we evaluate the relationship of these factors with the diversity of bryophytes in the Macaronesian region (Azores, Madeira, Canary Islands and Cape Verde). The predictive power of EMIB, habitat diversity, climate and the GDM on total bryophyte richness, as well as moss and liverwort richness (the two dominant bryophyte groups), was evaluated through ordinary least squares regressions. After choosing the best subset of variables using inference statistics, we used partial regression analyses to identify the independent and shared effects of each model. The variables included within each model were similar for mosses and liverworts, with orographic mist layer being one of the most important predictors of richness. Models combining climate with either the GDM or habitat diversity explained most of richness variation (up to 91%). There was a high portion of shared variance between all pairwise combinations of factors in mosses, while in liverworts around half of the variability in species richness was accounted for exclusively by climate. Our results suggest that the effects of climate and habitat are strong and prevalent in this region, while geographical factors have limited influence on Macaronesian bryophyte diversity. Although climate is of great importance for liverwort richness, in mosses its effect is similar to or, at least, indiscernible from the effect of habitat diversity and, strikingly, the effect of island ontogeny. These results indicate that for highly vagile taxa on oceanic islands, the dispersal process may be less important for successful colonization than the availability of suitable ecological

  3. Geographical, temporal and environmental determinants of bryophyte species richness in the Macaronesian islands.

    Directory of Open Access Journals (Sweden)

    Silvia C Aranda

    Full Text Available Species richness on oceanic islands has been related to a series of ecological factors including island size and isolation (i.e. the Equilibrium Model of Island Biogeography, EMIB, habitat diversity, climate (i.e., temperature and precipitation and more recently island ontogeny (i.e. the General Dynamic Model of oceanic island biogeography, GDM. Here we evaluate the relationship of these factors with the diversity of bryophytes in the Macaronesian region (Azores, Madeira, Canary Islands and Cape Verde. The predictive power of EMIB, habitat diversity, climate and the GDM on total bryophyte richness, as well as moss and liverwort richness (the two dominant bryophyte groups, was evaluated through ordinary least squares regressions. After choosing the best subset of variables using inference statistics, we used partial regression analyses to identify the independent and shared effects of each model. The variables included within each model were similar for mosses and liverworts, with orographic mist layer being one of the most important predictors of richness. Models combining climate with either the GDM or habitat diversity explained most of richness variation (up to 91%. There was a high portion of shared variance between all pairwise combinations of factors in mosses, while in liverworts around half of the variability in species richness was accounted for exclusively by climate. Our results suggest that the effects of climate and habitat are strong and prevalent in this region, while geographical factors have limited influence on Macaronesian bryophyte diversity. Although climate is of great importance for liverwort richness, in mosses its effect is similar to or, at least, indiscernible from the effect of habitat diversity and, strikingly, the effect of island ontogeny. These results indicate that for highly vagile taxa on oceanic islands, the dispersal process may be less important for successful colonization than the availability of suitable

  4. Detailed analysis of the Canary on-sky results at the WHT using Rayleigh laser guide stars

    Science.gov (United States)

    Martin, O.; Gendron, É.; Morris, T.; Basden, A.; Hubert, Z.; Gratadour, D.; Osborn, J.; Vidal, F.; Chemla, F.; Rousset, G.; Myers, R.

    2014-07-01

    CANARY is the multi-object adaptive optics (MOAO) on-sky demonstrator developed by Durham University and LESIA Observatoire de Paris, in the perspective of the E-ELT. Since 2013, CANARY has been operating with 3 off-axis NGS and 4 off-axis Rayleigh LGS and compensating for one on-axis NGS observed with a near IR camera and the Truth Sensor (TS) for diagnostic purpose. In this paper, we present the tomographic performance of CANARY during the runs in 2013. We propose a detailed analysis of the tomographic error leading to the establishment of the CANARY wave-front error budget. In particular we are able to evaluate the tomographic error for each altitude in the atmosphere for a given reconstructor by modelling a set of one-layer covariance matrices. This tool allows us to understand the tradeoffs to be made in the building of the tomographic reconstructor. We present two methods for the wavefront error budget computation. The DTI one uses input system parameters and open loop WFS slopes to estimate the error in a number of independent terms. The DMTS method directly uses the Truth Sensor measurements to estimate the error. We show a good agreement between the two approaches making us confident in our modelling of the instrument. We derive estimations of the Strehl ratio from the error variance and compare them to the recorded IR image Strehl ratio. We find a good agreement between the two, hence validating our wavefront error analysis. Finally we present an on-sky validation of the tomographic reconstruction using LGS based on GLAO and MOAO data. We also quantify the gain brought by the LGS, comparing results obtained in MOAO with 3 NGS and with or without LGS in the wavefront measurements.

  5. Male Osteoporosis

    Directory of Open Access Journals (Sweden)

    Meltem Esenyel

    2004-03-01

    Full Text Available Osteoporosis in men is now recognized as an increasingly important public health issue. About 30 % of hip fractures and 20 % of vertebral fractures occur in men. In the present study, we examined 19 men who did not have major risk factors that might affect bone mass. Parathormone(PTH, osteocalcin (marker of bone formation, OC and deoxypyridinoline (marker of bone resorption, DPD were measured. The bone mineral density (BMD measurements in 16 men were performed by dual-energy X-ray absorbtiometry (DXA from lumbar spine (L2-4, and left hip. Bone density at each site was categorized as osteoporosis or osteopenia according to World Health Organization (WHO criteria. In 19 patients with a mean age of 69 years, PTH levels were in the normal range except one patient. OC levels were elevated in %42.1 and DPD levels were elevated in 74 % of patients. L2-4 T score was osteoporotic (25% in 4 patients and osteopenic (25% in 4 patients. Femur Ward’s T score was osteoporotic (37.5% in 7 patients and osteopenic (37.5% in 7 patients. Osteoporosis is a significant problem in older men. Increased awareness for the risk factors of male osteoporosis is an important issue. Early diagnosis and treatment would help to reduce morbidity and mortality resulting from osteoporotic fractures.

  6. Shemya Island prehistory

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The 752 artifacts described in this paper are from 5 sites on Shemya Island. Artifactual evidence suggests the island had a small resident population and was...

  7. Classifying Pacific islands

    Science.gov (United States)

    Nunn, Patrick D.; Kumar, Lalit; Eliot, Ian; McLean, Roger F.

    2016-12-01

    An earth-science-based classification of islands within the Pacific Basin resulted from the preparation of a database describing the location, area, and type of 1779 islands, where island type is determined as a function of the prevailing lithology and maximum elevation of each island, with an island defined as a discrete landmass composed of a contiguous land area ≥1 ha (0.01 km2) above mean high-water level. Reefs lacking islands and short-lived (ocean setting as well as the biological attributes of Pacific islands. It may also be used in spatial assessments of second-order phenomena associated with the islands, such as their vulnerability to various disasters, coastal erosion, or ocean pollution as well as human populations, built infrastructure and natural resources.