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1

Recent, slow normal and strike-slip faulting in the Pasto Ventura region of the southern Puna Plateau, NW Argentina  

USGS Publications Warehouse

Recent normal and strike-slip faulting on the Puna Plateau of NW Argentina has been linked to lithospheric foundering, gravitational spreading, plate boundary forces and a decrease in crustal shortening from north to south. However, the timing, kinematics and rate of extension remain poorly constrained. We focus on the Pasto Ventura region (NW Argentina) located on the southern Puna Plateau and recent deformation (<1 Ma). Field mapping and kinematic analysis across offset volcanic cinder cones show that the overall extension direction is subhorizontal, is oriented NE-SW to NNE-SSW, and occurs at a slow, time-integrated rate of 0.02 to 0.08 mm/yr since at least 0.8–0.5 Ma. A regional compilation from this study and existing data shows that recent extension across the Puna Plateau is subhorizontal but varies in azimuthal orientation dramatically. Data from the Pasto Ventura region are consistent with a number of models to explain normal and strike-slip faulting on the Puna Plateau, all of which likely influence the region. Some role for lower lithospheric foundering through dripping appears to be seen based on the regional extension directions and ages of mafic volcanism in the southern Puna Plateau.

Zhou, Renjie; Schoenbohm, Lindsay M.; Cosca, Michael

2013-01-01

2

CARACTERIZACIÓN DE LA DIVERSIDAD DEL PASTO NATIVO Bouteloua curtipendula Michx. Torr. MEDIANTE MARCADORES DE AFLP NATIVE GRASS Bouteloua curtipendula Michx. Torr. DIVERSITY CHARACTERIZATION USING AFLP MARKERS  

Microsoft Academic Search

El pasto Banderita (Bouteloua curtipendula) Michx. (Torr.), es una especie nativa de México, pero no se ha hecho un uso plani- ficado de su riqueza genética. Para determinar relaciones genéti- cas en 90 poblaciones nativas de Banderita, de varios Estados de México, se analizó la expresión de marcadores de polimorfismo de longitud de fragmentos amplificados (AFLP) y su consisten- cia,

Carlos Morales-Nieto; Adrián Quero-Carrillo; Olivier Le-Blanc; Alfonso Hernández-Garay; Jorge Pérez-Pérez; Sergio González-Muñoz

2006-01-01

3

Climate and environment of the earliest West European hominins inferred from amphibian and squamate reptile assemblages: Sima del Elefante Lower Red Unit, Atapuerca, Spain  

NASA Astrophysics Data System (ADS)

The Sima del Elefante cave, in the Sierra de Atapuerca (Burgos, Spain), is famous for the fact that level TE9 of its Lower Red Unit recently delivered the oldest hominin remains of Western Europe, identified as Homo antecessor and dated by biostratigraphy and radiometric methods to ca 1.2 Ma. Given the importance of this discovery, every effort is being made to reconstruct the landscapes where these hominins once thrived. The amphibian and squamate reptile assemblage of the Sima del Elefante Lower Red Unit is here studied for the first time. The faunal list comprises at least 17 species (roughly 12,000 bone fossil remains): Salamandra salamandra, Triturus cf. marmoratus, Alytes obstetricans, Pelobates cultripes, Pelodytes punctatus, Bufo bufo, Bufo calamita, Hyla arborea, Rana sp., cf. Pelophylax sp., Lacerta s.l., small-sized indeterminate lacertids, Anguis fragilis, Natrix cf. natrix, Natrix cf. maura, Coronella cf. girondica and Vipera sp. As the amphibians and squamate reptiles do not differ at species level from the extant herpetofauna of the Iberian Peninsula, they can contribute to the reconstruction of the landscape and climate. In this paper, the mutual climatic range and habitat weighting methods are applied to the amphibian and squamate reptile assemblages in order to estimate quantitative data. The results from the squamate and amphibian study indicate that during the hominin presence the mean annual temperature (MAT = 10-13 °C) was always slightly warmer than at present and the mean annual precipitation (MAP = 800-1000 mm) was greater than today in the Burgos area. The landscape had open habitats in the vicinity of the Atapuerca caves throughout the sequence, with wet points in the surrounding area, and a predominance of humid meadows and open woodlands. These results mainly agree with those for large mammals, small mammals and the pollen analysis. The climate and landscape of TE-LRU are very similar to those reconstructed for the TD6 "Aurora Stratum" level of the Gran Dolina cave (Atapuerca) that has yielded H. antecessor remains at ca 960 ky. When compared with Orce localities of similar age (i.e. Barranco León D and Fuente Nueva 3) that have yielded strong evidence of hominin presence (mainly lithic industries), it appears that they have a fairly similar environmental pattern, having in common a good representation of woodland and water-edge areas, even though dry environments are more developed in Barranco León D and Fuente Nueva 3 than in Sima del Elefante and Gran Dolina. H. antecessor may have thus lived under a warm-humid climate in a patchy landscape mainly composed of humid meadows and riparian woodlands. Such a landscape may have provided favourable conditions for a high diversity of large mammals, as well as for hiding and escaping from large carnivores.

Blain, Hugues-Alexandre; Bailon, Salvador; Cuenca-Bescós, Gloria; Bennàsar, Maria; Rofes, Juan; López-García, Juan Manuel; Huguet, Rosa; Arsuaga, Juan Luis; Bermúdez de Castro, José Maria; Carbonell, Eudald

2010-11-01

4

PASTOS Y PAISAJES LAWNS & LANDSCAPES  

E-print Network

the quarantine zone. Specific inspection sites included tree services, municipal parks, landfills/ disposal sites nine-acre site and the surrounding 1½ mile area were quarantined. This quarantine restricted surveys were done on locations that may have received trees, branches, or other waste wood from within

Goodman, Robert M.

5

PASTOS Y PAISAJES WINTER 2005 VOLUMEN 4 -NUMERO 1  

E-print Network

Words from the Editor 1 Cedar Apple Rust ­ A Springtime Disease You Can't Miss! 1 The Benefits of Winter of the turf in the state giving us the opportunity to look up at the trees. Enjoy. Cedar Apple Rust will not produce as much disease pressure as an entire week or month, especially if it's during bud break and early

Goodman, Robert M.

6

Words From the Editor Welcome to the first issue of `Pastos y Paisajes'.  

E-print Network

. Aplique aproximadamente 1 pulgada de agua por semana (combinacion de lluvia y riegación). Sobre Siembra ayuda también a producir un césped mas denso. Riego. Los céspedes requieren el agua durante el otoño ligeras de agua mientras las semillas germinan. La Yedra Venenosa Por Pedro Perdomo Tengan cuidado con la

Goodman, Robert M.

7

Los Elefantes Rosas en las Cupulas en la Legislatura: An Empirical Analysis of the Texas Education Finance Mechanism with Special Emphasis on Bilingual Education  

ERIC Educational Resources Information Center

The State of Texas' education finance mechanism--known as the Foundation School Program (FSP)--was challenged in a series of litigation known as "Edgewood v. Kirby I-IV" and "West Orange Cove I-II". Though the state Supreme Court's holding ultimately moved the Texas Assembly to make changes in the funding mechanism, not since the 1980s has there…

Rolle, Anthony; Torres, Mario; Eason, Noelle

2010-01-01

8

CARACTERIZACIÓN MORFOLÓGICA DE POBLACIONES NATIVAS DE PASTO BANDERITA (Bouteloua curtipendula (Michx.) Torr.) EN MÉXICO MORPHOLOGICAL CHARACTERIZATION OF NATIVE POPULATIONS OF SIDEOAT GRAMA (Bouteloua curtipendula (Michx.) Torr.) IN MÉXICO  

Microsoft Academic Search

The morphological descriptors involve the management of attributes to carry out breeding of forage species. The objectives of the present study were to explore the morphological diversity of native populations of sideoat grama (Bouteloua curtipendula (Michx.) Torr.) and to evaluate its principal morphological characteristics. To this effect, 177 ecotypes were qualified and analyzed at the moment of flowering by means

Carlos R. Morales-Nieto; Adrián Quero-Carrillo; Jorge Pérez-Pérez; Alfonso Hernández-Garay; Olivier Le-Blanc

2008-01-01

9

Avaliação do desempenho animal e do pasto na mistura aveia IAPAR 61 (Avena strigosa Schreb) e ervilha forrageira (Pisum arvense L.) manejada em diferentes alturas  

Microsoft Academic Search

The objective of the work was evaluate the effect of different sward heights (8.9, 10.0, 11.3, 11.9, 13.4, 13.6, 14.7, and 18.3 cm) of a mixture of black oat cv IAPAR 61 (Avena strigosa Schreb) + field pea (Pisum arvense L.) on the average daily liveweight gain (DLG), weight gain\\/ha (WGP\\/ha), stocking rate (animals.day\\/ha), botanical composition, residue of dry matter

Marcia Maria Grise; Ulysses Cecato; Anibal de Moraes; Paulo César Carvalho Faccio; Marco Weber do Canto; Clóves Cabreira Jobim; Augusto Manoel Rodrigues

2002-01-01

10

CARACTERÍSTICAS DA CARCAÇA DE CORDEIROS MANTIDOS EM PASTO DE AZEVÉM COMUM (Lolium multiflorum Lam), EM PASTEJO CONTÍNUO, SUBMETIDOS A DIFERENTES NÍVEIS DE ADUBAÇÃO NITROGENADA 1  

Microsoft Academic Search

The experiment evaluated the effect of the levels of nitrogen fertilization, of italian ryegrass (Lolium multiflorum Lam.), on the characteristics of carcass of lambs kept in continuous stocking. There where four doses of nitrogen (N), using commercial urea (45-00-00), with only application: T1 - level 0 of N \\/hectare (ha); T2 - 75 kg of N \\/ha; T3 - 150

Luiz Giovani de Pellegrini; Alda Lúcia Gomes Monteiro; Mikael Neumann; Aníbal de Moraes; Amadeu Bona Filho; Luciane Rodrigues Cardoso

11

Análisis morfológico de la diversidad del pasto navajita (Bouteloua gracilis (Willd. ex Kunth) Lag. ex Steud.), en Chihuahua, México Morphological analysis of blue grama grass (Bouteloua gracilis (Willd. ex Kunth) Lag. ex Griffiths) diversity in Chihuahua, Mexico  

Microsoft Academic Search

An efficient morphologic characterization of plants includes evaluation of forage traits. The objective was to analyze morphologic diversity in native populations of blue grama grass (Bouteloua gracilis (Willd. ex Kunth) Lag. ex Steud.) in Chihuahua. In 2006, 173 ecotypes were collected in Chihuahua and transplanted in La Campana Experimental Site. Ecotypes were evaluated through morphological traits and their population structure

Carlos Morales Nieto; Luis Madrid Pérez; Alicia Melgoza Castillo; Martín Martínez

12

Caracterización bioquímica del pasto marino Zostera marina en el límite sur de su distribución en el Pacífico Norte Biochemical characterization of the eelgrass Zostera marina at its southern distribution limit in the North Pacific  

Microsoft Academic Search

The eelgrass Zostera marina L. is distributed along the Baja California Peninsula (Mexico) where it is exposed to a wide range of irradiances and temperatures that could promote changes in its biochemical composition. Consequently, the objective of this study was to characterize the variations in the levels of chlorophyll, carbohydrates, proteins, fiber, ash and calories in the shoots of Z.

Alejandro Cabello-Pasini; Raquel Muñiz-Salazar; David H. Ward

13

Diversidad forrajera del pasto banderita (Bouteloua curtipendula (Michx.) Torr.), en poblaciones de zonas áridas y semiáridas de México Forage diversity of sideoats grama (Bouteloua curtipendula (Michx.) Torr.) populations in arid and semiarid regions of Mexico  

Microsoft Academic Search

The objectives of the present study were to evaluate sideoats grama (Bouteloua curtipendula (Michx.) Torr.) populations, to set an ex situ plot, and to asses morphological diversity. From 2000 to 2003, 577 sideoats grama populations were collected in 13 Mexican States. In 177 established ecotypes, the following plant morphologic attributes were assessed: vigour, regrowth, forage texture, dry matter production potential,

Carlos Raúl Morales Nieto; Adrián Quero Carrillo; Alicia Melgoza Castillo; Martín Martínez Salvador; Pedro Jurado Guerra

2009-01-01

14

Influencia de la fecha de siembra y distancia entre surcos sobre el establecimiento de asociaciones de desmanthus y el pasto klein Influence of row-spacing and planting date on the establishment of bundleflower-kleingrass mixtures  

Microsoft Academic Search

Understanding factors that affect the establishment of pastures is important to the management of persistent grass-legume mixtures. The objective of this study was to evaluate kleingrass (Panicum coloratum L.)-bundeflower (Desmanthus sp.) associations during the establishment year in terms of plant density and yield. The study was carried out at Brazos County, TX. (near College Station). Plots were drilled at a

Eduardo A. González Valenzuela; Mark A. Hussey

15

Evidence for wheat-rye nucleolar competition (amphiplasty) in triticale by silver-staining procedure  

Microsoft Academic Search

Amphiplasty in hexaploid triticale, the artificial amphiploid of tetraploid wheat and diploid rye, is analyzed for the first time using a modified, highly reproducible, silver-staining procedure. A comparative analysis of metaphase somatic cells by phase contrast, C-banding and silver-staining of the hexaploid triticale cv. ‘Cachirulo’ and its parents, namely, the tetraploid durum wheat cv. ‘Enano de Andujar’ and the diploid

J. R. Lacadena; M. C. Cermeño; J. Orellana; J. L. Santos

1984-01-01

16

INHIBICIÓN DEL CRECIMIENTO DE CHUFA (Cyperus esculentus) Y PASTO BERMUDA (Cynodon dactylon) CON MULCH VEGETAL PROVENIENTE DE CENTENO (Secale cereale) EN VIDES Growth inhibition of yellow nutsedge (Cyperus esculentus) and bermuda grass (Cynodon dactylon) by a mulch derived from rye (Secale cereale) in grapevines  

Microsoft Academic Search

Two field trials (Los Andes 1998-1999 and Santiago 2004-2005) were carried out to determine growth inhibition of yellow nutsedge (Cyperus esculentus L.) and bermuda grass (Cynodon dactylon (L.) Pers.) growing on the planted row produced by a mulch derived from a rye (Secale cereale L.) cover crop established between grapevine (Vitis vinifera L.) rows on overhead (cv. Flame Seedless) and

Juan Ormeño-Núñez; Gerardo Pino-Rojas; Farouk Garfe-Vergara

17

Use of digital multispectral videography to assess seagrass distribution in San Quinti??n Bay, Baja California, Mexico [Uso de videografi??a multiespectral digital para evaluar la distributio??n del pasto marino en Bahi??a San Quinti??n, Baja California, Me??xico  

USGS Publications Warehouse

Apparent threats to the spatial distribution of seagrass in San Quinti??n Bay prompted us to make a detailed assessment of habitats in the bay. Six coastal habitats and three seagrass subclasses were delineated using airborne digital multispectral videography (DMSV), Eelgrass, Zostera marina, was the predominant seagrass and covered 40% (1949 ha) of the areal extent of the bay in 1999. Eelgrass grew over a wide range of tidal depths from about -3.0 in mean lower low water (MLLW) to about 1.0 m MLLW, but greatest spatial extent occurred in intertidal areas -0.6 m to 1.0 m MLLW. Exposed-continuous (i.e., high density) eelgrass was the most abundant habitat in the bay. Widgeongrass, Ruppia maritima, was the only other seagrass present and covered 3% (136 ha) of the areal extent of the entire bay. Widgeongrass grew in single species stands in the upper intertidal (??? 0.4 MLLW) and intermixed with eelgrass at lower tidal depths. Overall accuracy of the six habitat classes and three subclasses in the DMSV map was relatively high at 84%. Our detailed map of San Quintin Bay can be used in future change detection analyses to monitor the health of seagrasses in the bay.

Ward, D.H.; Tibbitts, T.L.; Morton, A.; Carrera-Gonzalez, E.; Kempka, R.

2004-01-01

18

Biochemical characterization of the eelgrass Zostera marina at its southern distribution limit in the North Pacific [Caracterizacio??n bioqui??mica del pasto marino Zostera marina en el li??mite sur de su distribucio??n en el Paci??fico Norte  

USGS Publications Warehouse

The eelgrass Zostera marina L. is distributed along the Baja California Peninsula (Mexico) where it is exposed to a wide range of irradiances and temperatures that could promote changes in its biochemical composition. Consequently, the objective of this study was to characterize the variations in the levels of chlorophyll, carbohydrates, proteins, fiber, ash and calories in the shoots of Z. marina from the north (San Quintin) and south (Ojo de Liebre and San Ignacio lagoons) of the peninsula. Temperature in the southern lagoons was 5-6??C higher than in the northern lagoon; likewise, in situ irradiance was two-fold greater in the south than in the north. As a result of the lower irradiance levels, the concentration of chlorophyll in the shoots of Z. marina was twice as high (1.7 mg gWW-1) in the northern lagoon than in the southern ones (0.8 mg gWW-1). Similar to chlorophyll levels, the concentration of soluble carbohydrates in the shoots was greater in the northern lagoon than in the southern ones, suggesting that the high levels of chlorophyll are enough to compensate for the low irradiance levels and to maintain a positive carbon balance at San Quintin. On the other hand, the levels of proteins in the shoots from the north of the peninsula were slightly lower than those from the southern populations. In general, these results suggest that the different environmental conditions to which Z. marina is exposed along the peninsula impact its biochemical composition.

Cabello-Pasini, A.; Muniz-Salazar, R.; Ward, D.H.

2004-01-01

19

Conservation Biology, Pages 16381646 Volume 16, No. 6, December 2002  

E-print Network

regiones mixtas y de pastos altos, Cistothorus platensis y Spizella pallida usaron tanto parches extensos to geographic variation in local and landscape structure. Sedge Wrens (Cistothorus platen- sis) and Clay

20

Serologic Evidence that Ascaris and Toxoplasma Infections Impact Inflammatory Responses to Helicobacter pylori in Colombians  

E-print Network

Background: Helicobacter pylori-infected children from coastal Tumaco, Colombia, have more parasitism, and adults have lower gastric cancer risk compared with high-altitude Pasto/Tuquerres residents. Because helminth and ...

Ek, Courtney

21

Proyecto para desarrollar un 'Teatro Popular Identificador'.  

E-print Network

se encargue de ellos en los infiernos. . . . RAÍCES PARA UN TEATRO NACIONAL POPULAR. La diversidad de elementos teatrales existentes en las farsas carnavalescas de la Costa Atlántica y otras regiones del país —Blancos y Negros en Pasto y Tumaco...

Zapata Olivella, Manuel

1975-10-01

22

Effects of Nitrogen Availability and Cheatgrass Competition on the Establishment of Vavilov Siberian Wheatgrass  

E-print Network

, OR 97331, USA. Abstract Cheatgrass (Bromus tectorum L.) is the most widespread invasive weed in sagebrush colgante (Bromus tectorum L.) es el pasto invasor ma´s comu´n en los ecosistemas de artemisia de Norteame

23

Dominant Language Transfer in Spanish Heritage Speakers and Second Language Learners in the Interpretation of Definite Articles  

ERIC Educational Resources Information Center

This study investigates dominant language transfer (from English) in adult Spanish second language (L2) learners and Spanish heritage speakers. We focus on contrasting properties of English and Spanish definite articles with respect to generic reference ("Elephants have ivory tusks" vs. "Los elefantes tienen colmillos de marfil") and inalienable…

Montrul, Silvina; Ionin, Tania

2012-01-01

24

J. Field Ornithol. 82(2):140149, 2011 DOI: 10.1111/j.1557-9263.2011.00316.x Nest-site selection and productivity of Vesper Sparrows  

E-print Network

selection and productivity of ground-nesting Vesper Sparrows (Pooecetes gramineus) across sites productividad en Pooecetes gramineus anidando en h´abitats de pastoreo El pastoreo de ganado en pastos de estepa lugares de anidaci´on y productividad de Pooecetes gramineus que anida en el suelo a trav´es de lugares

25

Challenges in predicting ?rxnG in solution: the mechanism of ether-catalyzed hydroboration of alkenes.  

PubMed

Ab initio (coupled-cluster and density-functional) calculations of Gibbs reaction energies in solution, with new entropy-of-solvation damping terms, were performed for the ether-catalyzed hydroboration of alkenes. The goal was to test the accuracy of continuum-solvation models for reactions of neutral species in nonaqueous solvents, and the hope was to achieve an accuracy sufficient to address the mechanism in the "Pasto case": B2H6 + alkene in THF solvent. Brown's SN2/SN1 "dissociative" mechanism, of SN2 formation of borane-ether adducts followed by SN1 alkene attack, was at odds with Pasto's original SN2/SN2 hypothesis, and while Brown could prove his mechanism for a variety of cases, he could not perform the experimental test with THF adducts in THF solvent, where the higher THF concentrations might favor an SN2 second step. Two diboranes were tested: B2H6, used by Pasto, and (9BBN)2 (9BBN = 9-borabicyclo[3.3.1]nonane, C8H15B), used by Brown. The new entropy terms resulted in improved accuracy vs traditional techniques (?2 kcal mol(-1)), but this accuracy was not sufficient to resolve the mechanism in the Pasto case. PMID:25470299

Sandbeck, Daniel J S; Kuntz, Colin M; Luu, Christine; Mondor, Rachelle A; Ottaviano, John G; Rayer, Aravind V; Sumon, Kazi Z; East, Allan L L

2014-12-18

26

Why Range Forage Quality Changes (Spanish)  

E-print Network

las herb?ceas y arbus- tivas, lo que hace a estas partes de los pastos m?s dif?ciles de digerir. Comparadas con las plantas de crecimiento de verano, las plantas de crecimiento invernal tienen mejor digestibilidad y mayor contenido de prote?- na cruda...

Lyons, Robert K.; Machen, Richard V.; Forbes, T. D. A.

2001-09-10

27

Contributed Papers Impact of Grazing Intensity during Drought in an  

E-print Network

(Bromus tectorum L.). A twofold increase in plant cover by exotic species followed a severe drought management plans that anticipate this variation. Keywords: Bromus tectorum, cheatgrass, climatic variation, particularmente de pasto ex´otico Bromus tectorum L. Despu´es de una sequ´ia severa la cobertura de especies ex

Sisk, Thomas D.

28

Land-Grant Universities and their Continuing Challenge.  

ERIC Educational Resources Information Center

A series of essays address the question: What can and might we expect of the land-grant system and values today and in the future? The essays include: what's ahead for the land-grant colleges (Ralph K. Huitt); the land-grant university, myth and reality (David Madsen); colleges of agriculture revisited (Henry R. Fortmann, Jerome K. Pasto, Thomas…

Anderson, G. Lester, Ed.

29

Effects of acid suppression and bismuth medications on the performance of diagnostic tests for Helicobacter pylori infection  

Microsoft Academic Search

OBJECTIVE: This study was designed to investigate whether acid suppression and bismuth medications interfere with the performance of diagnostic tests for Helicobacter pylori (H. pylori) infection.METHODS: Sixty patients with previous diagnoses of atrophic gastritis and H. pylori infection made in gastric biopsies taken at Hospital Departmental, Pasto, Colombia, were enrolled in the study. 13C breath urea test (UBT) and stool

Luis E. Bravo; J. Luis Realpe; Cristina Campo; Robertino Mera; Pelayo Correa

1999-01-01

30

Investigacin Centro de Investigacin y de Estudios Avanzados del Instituto Politcnico Nacional  

E-print Network

Nacional Unidad Mérida Recursos del Mar Investigador Línea de Investigación Luz María Dalila Aldana Aranda, fitoplancton, pastos marinos y manglares. Jesús Ernesto Arias González Ecología del paisaje, conectividad

31

Contributed Paper Rapid Assessment of Risks to a Mobile Marine  

E-print Network

Protegida a Escala de Ecosistema Resumen: Las redes de ´areas marinas protegidas (AMPs) a escala de pastos marinos: uso de redes, cacer´ia por nativos, pesca con redes de arrastre, tr´afico de nav´ios y riesgo, se tendr´ia que disminuir el uso de redes comerciales y la cacer´ia por nativos en ´areas remotas

Marsh, Helene

32

The first hominin of Europe.  

PubMed

The earliest hominin occupation of Europe is one of the most debated topics in palaeoanthropology. However, the purportedly oldest of the Early Pleistocene sites in Eurasia lack precise age control and contain stone tools rather than human fossil remains. Here we report the discovery of a human mandible associated with an assemblage of Mode 1 lithic tools and faunal remains bearing traces of hominin processing, in stratigraphic level TE9 at the site of the Sima del Elefante, Atapuerca, Spain. Level TE9 has been dated to the Early Pleistocene (approximately 1.2-1.1 Myr), based on a combination of palaeomagnetism, cosmogenic nuclides and biostratigraphy. The Sima del Elefante site thus emerges as the oldest, most accurately dated record of human occupation in Europe, to our knowledge. The study of the human mandible suggests that the first settlement of Western Europe could be related to an early demographic expansion out of Africa. The new evidence, with previous findings in other Atapuerca sites (level TD6 from Gran Dolina), also suggests that a speciation event occurred in this extreme area of the Eurasian continent during the Early Pleistocene, initiating the hominin lineage represented by the TE9 and TD6 hominins. PMID:18368116

Carbonell, Eudald; Bermúdez de Castro, José M; Parés, Josep M; Pérez-González, Alfredo; Cuenca-Bescós, Gloria; Ollé, Andreu; Mosquera, Marina; Huguet, Rosa; van der Made, Jan; Rosas, Antonio; Sala, Robert; Vallverdú, Josep; García, Nuria; Granger, Darryl E; Martinón-Torres, María; Rodríguez, Xosé P; Stock, Greg M; Vergès, Josep M; Allué, Ethel; Burjachs, Francesc; Cáceres, Isabel; Canals, Antoni; Benito, Alfonso; Díez, Carlos; Lozano, Marina; Mateos, Ana; Navazo, Marta; Rodríguez, Jesús; Rosell, Jordi; Arsuaga, Juan L

2008-03-27

33

Identification of the Calderas for Major Ignimbrites of the Altiplano-Puna Volcanic Complex, Central Andes, Including Two New Super-eruptions  

NASA Astrophysics Data System (ADS)

The Neogene ignimbrite flare-up in the Altiplano-Puna Volcanic Complex (APVC) in the central Andes produced calderas and ignimbrites covering >70,000 km2 in Chile, Bolivia, and Argentina and totaling >11,000 km3 of magma. One of the questions related to this extraordinary occurrence is how long it took for these ignimbrites to be emplaced. In an effort to determine this, we have combined field correlations, high-precision 40Ar/39Ar dating, anisotropy of magnetic susceptibility (AMS) and characteristic remanent magnetism (ChRM) to constrain the dates of the eruptions. Herein we present the paleomagnetic data and preliminary interpretations, including the definition of two new super-eruptions in the APVC (including the youngest yet identified in the APVC). Several ignimbrites occupy similar stratigraphic positions. The Pastos Grandes and Tara Ignimbrites erupted 2.8-3.5 Ma, while the Chuhuilla, Alota, and Guacha Ignimbrites date between 5.3 and 5.6 Ma. The Pastos Grandes and Tara Ignimbrites have similar ChRM directions. The ChRM directions of the Alota and Guacha Ignimbrites are clearly distinct but the Chuhuilla Ignimbrite data have very large dispersion. The thermal demagnetization reveals a single component in nearly all the samples, which may indicate that the ignimbrites were emplaced above the magnetite Curie temperature. Current efforts center on refining and reducing the errors on the ChRM directions. AMS was used to determine flow directions and thus define the source areas for ignimbrites. The 3.51 Ma Tara Ignimbrite, first recognized as ponded ignimbrite in La Pacana caldera and thought to be erupted from there, is sourced in the Guacha caldera of Bolivia, likely from the western dome complex, which yields similar dates. Great thicknesses of Tara Ignimbrite are ponded within the Guacha caldera, and also around Cerro Zapaleri. This is the youngest super-eruption in the central APVC. The Pastos Grandes caldera was previously thought to have formed during the Chuhuilla Ignimbrite eruption at 5.45 Ma. Our AMS data show the Pastos Grandes Ignimbrite was erupted from the Pastos Grandes caldera and new dates show it was emplaced at 2.89 Ma, corroborated by the ChRM data. It is exposed over 6000 km2 with a volume of >800 km3, making it the youngest super-eruption in the APVC. This may have been the reactivation of the caldera after a ~2.5 million year hiatus in ignimbrite-forming eruptions. Our AMS data confirm that the Guacha, Laguna Colorado, and Vilama ignimbrites come from their eponymous calderas, with some topographic effects upon the flow directions.

Ort, M. H.; de Silva, S. L.; Jiménez, N.

2008-12-01

34

In vitro digestibility, physicochemical, thermal and rheological properties of banana starches.  

PubMed

Banana starches (BS) were isolated from Enano, Morado, Valery and Macho cultivars. The BS possessed B-type crystallinity and an amylose content varying from 19.32 to 26.35%. Granules had an oval morphology with different major-to-minor axis ratios, exhibiting both mono- and bi-modal distributions and mean particle sizes varying from 32.5 to 45 ?m. BS displayed zeta-potential values ranging between -32.25 and -17.32 mV, and formed gels of incipient to moderate stability. The enthalpy of gelatinization of BS affected the crystalline order stability within the granules. In-vitro digestibility tests showed fractions as high as 68% of resistant starch. Rheological oscillatory tests at 1 Hz showed that BS dispersions (7.0%, w/w) exhibited Type III behaviour, attributed to the formation of a continuous phase complex three-dimensional amylose gel reinforced by swollen starch granules acting as fillers. Amylose content and granules morphology were the main factors influencing the BS properties. PMID:24299760

Utrilla-Coello, R G; Rodríguez-Huezo, M E; Carrillo-Navas, H; Hernández-Jaimes, C; Vernon-Carter, E J; Alvarez-Ramirez, J

2014-01-30

35

Meta-Analysis of Attitudes toward Damage-Causing Mammalian Wildlife  

PubMed Central

Many populations of threatened mammals persist outside formally protected areas, and their survival depends on the willingness of communities to coexist with them. An understanding of the attitudes, and specifically the tolerance, of individuals and communities and the factors that determine these is therefore fundamental to designing strategies to alleviate human-wildlife conflict. We conducted a meta-analysis to identify factors that affected attitudes toward 4 groups of terrestrial mammals. Elephants (65%) elicited the most positive attitudes, followed by primates (55%), ungulates (53%), and carnivores (44%). Urban residents presented the most positive attitudes (80%), followed by commercial farmers (51%) and communal farmers (26%). A tolerance to damage index showed that human tolerance of ungulates and primates was proportional to the probability of experiencing damage while elephants elicited tolerance levels higher than anticipated and carnivores elicited tolerance levels lower than anticipated. Contrary to conventional wisdom, experiencing damage was not always the dominant factor determining attitudes. Communal farmers had a lower probability of being positive toward carnivores irrespective of probability of experiencing damage, while commercial farmers and urban residents were more likely to be positive toward carnivores irrespective of damage. Urban residents were more likely to be positive toward ungulates, elephants, and primates when probability of damage was low, but not when it was high. Commercial and communal farmers had a higher probability of being positive toward ungulates, primates, and elephants irrespective of probability of experiencing damage. Taxonomic bias may therefore be important. Identifying the distinct factors explaining these attitudes and the specific contexts in which they operate, inclusive of the species causing damage, will be essential for prioritizing conservation investments. Meta-Análisis de las Posturas hacia la Mamíferos Silvestres Causantes de Daños Resumen Muchas poblaciones de mamíferos amenazados persisten fuera de áreas protegidas formales y su supervivencia depende de la buena voluntad de las comunidades que coexisten con ellos. Un entendimiento de las posturas, y específicamente de la tolerancia, de los individuos y las comunidades y los factores que los determinan es fundamental para diseñar estrategias que alivien el conflicto humano – vida silvestre. Llevamos a cabo un meta-análisis para identificar los factores que afectaron las posturas hacia cuatro grupos de mamíferos terrestres. Los elefantes (65%) provocaron las posturas más positivas. Los siguieron los primates (55%), los ungulados (53%) y los carnívoros (44%). Los residentes urbanos presentaron las posturas más positivas (80%), seguidos por los granjeros comerciales (51%) y los granjeros comunales (26%). Un índice de tolerancia a los daños mostró que la tolerancia humana a los ungulados y primates fue proporcional a la probabilidad de experimentar daños mientras que los elefantes provocaron niveles de tolerancia más altos de lo esperado y los carnívoros provocaron niveles de tolerancia más bajos de lo esperado. Contrario a la sabiduría convencional, experimentar daños no fue siempre el factor dominante para determinar las posturas. Los granjeros comunales tuvieron una baja probabilidad de ser positivos hacia los carnívoros independientemente de la probabilidad de experimentar daños, mientras que los granjeros comerciales y los residentes urbanos tuvieron mayor probabilidad de ser positivos hacia los carnívoros independientemente de los daños. Los residentes urbanos tuvieron mayor probabilidad de ser positivos hacia los ungulados, los elefantes y los primates cuando la probabilidad de daños fue baja, pero no cuando fue alta. Los granjeros comerciales y comunales tuvieron una mayor probabilidad de ser positivos hacia los ungulados, los primates y los elefantes independientemen

KANSKY, RUTH; KIDD, MARTIN; KNIGHT, ANDREW T

2014-01-01

36

Combined ESR/U-series chronology of Acheulian hominid-bearing layers at Trinchera Galería site, Atapuerca, Spain  

USGS Publications Warehouse

The Sierra de Atapuerca, northern Spain, is known from many prehistoric and palaeontological sites documenting human prehistory in Europe. Three major sites, Gran Dolina, Galería and Sima del Elefante, range in age from the oldest hominin of Western Europe dated to 1.1 to 1.3 Ma (millions of years ago) at Sima del Elefante to c.a. 0.2 Ma on the top of the Galería archaeological sequence. Recently, a chronology based on luminescence methods (Thermoluminescence [TL] and Infrared Stimulated Luminescence [IRSL]) applied to cave sediments was published for the Gran Dolina and Galería sites. The authors proposed for Galería an age of 450 ka (thousands of years ago) for the units lower GIII and GII, suggesting that the human occupation there is younger than the hominid remains of Sima de los Huesos (>530 ka) around 1 km away. In this paper, we present new results obtained by combined Electron Spin Resonance/Uranium-series (ESR/U-series) dating on 20 herbivorous teeth from different levels at the Galería site. They are in agreement with the TL results for the upper part of the stratigraphic sequence (GIV and GIIIb), in the range of between 200 and 250 ka. But for the GIIIa to GIIb levels, the TL ages become abruptly older by 200 ka while ESR ages remain relatively constant. Finally, the TL and ESR data agree in the lowest part of the section (GIIa); both fall in the range of around 350–450 ka. Our results suggest a different interpretation for the GII, GIII and GIV units of Galería and the upper part of Gran Dolina (TD10 and TD11) than obtained by TL. The ESR/U-series results are supported by a Bayesian analysis, which allows a better integration between stratigraphic information and radiometric data.

Falguères, Christophe; Bahain, Jean-Jacques; Bischoff, James L.; Pérez-González, Alfredo; Ortega, Ana Isabel; Ollé, Andreu; Quilles, Anita; Ghaleb, Bassam; Moreno, Davinia; Dolo, Jean-Michel; Shao, Qingfeng; Vallverdú, Josep; Carbonell, Eudald; María Bermúdez de Castro, Jose; Arsuaga, Juan Luis

2013-01-01

37

Effects of Boron on Proton Transport and Membrane Properties of Sunflower (Helianthus annuus L.) Cell Microsomes.  

PubMed Central

Boron deficiency and toxicity inhibit ATP-dependent H+ pumping and vanadate-sensitive ATPase activity in sunflower roots and cell suspensions. The effects of boron on H+ pumping and on passive H+ conductance, as well as on fluorescence anisotropy in KI-washed microsomes isolated from sunflower (Helianthus annuus L. cv Enano) cell suspensions, have been investigated. Boron deficiency reduced the total and vanadate-sensitive ATPase activities as well as the vanadate-sensitive ATP-dependent H+ pumping without affecting the amount of antigenic ATPase protein as measured by immunoblotting with an Arabidopsis thaliana plasma membrane anti-H+-ATPase polyclonal antibody. Kinetic studies revealed that boron deficiency reduced Vmax of vanadate-sensitive ATPase activity with little change in the apparent Km for Mg2+-ATP. Proton leakage was greater in microsomal vesicles isolated from cells grown without boron and incubated in reaction medium without added boron, and this effect was reversed by addition of boron to the reaction medium. Fluorescence anisotropy indicated that diphenyl hexatriene and 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene probes were immobilized to a greater extent in microsomes from cells grown without boron than in those from cells grown with 100 [mu]M H3BO3. The apparent decrease of membrane fluidity in microsomes from cells grown without boron was reversed by the addition of boron to the reaction medium. Taken together these data suggest that inhibition of H+ gradient formation in microsomes from sunflower cells grown in the absence of boron could be due to the combined effects of reduced H+-ATPase activity and increased passive conductance across the membrane, possibly resulting from increased membrane rigidity. PMID:12231978

Ferrol, N.; Belver, A.; Roldan, M.; Rodriguez-Rosales, M. P.; Donaire, J. P.

1993-01-01

38

Seasonal plankton variability in Chilean Patagonia fjords: Carbon flow through the pelagic food web of Aysen Fjord and plankton dynamics in the Moraleda Channel basin  

NASA Astrophysics Data System (ADS)

Two research cruises ( CIMAR 13 Fiordos) were conducted in the N-S oriented macrobasin of the Moraleda Channel (42-47°S), which includes the E-W oriented Puyuhuapi Channel and Aysen Fjord, during two contrasting productive seasons: austral winter (27 July-7 August 2007) and spring (2-12 November 2007). These campaigns set out to assess the spatio-temporal variability, defined by the local topography along Moraleda Channel, in the biological, physical, and chemical oceanographic characteristics of different microbasins and to quantify the carbon budget of the pelagic trophic webs of Aysen Fjord. Seasonal carbon fluxes and fjord-system functioning vary widely in our study area. In terms of spatial topography, two constriction sills (Meninea and Elefantes) define three microbasins along Moraleda Channel, herein the (1) north (Guafo-Meninea), (2) central (Meninea-Elefantes), and (3) south (Elefantes-San Rafael Lagoon) microbasins. In winter, nutrient concentrations were high (i.e. nitrate range: 21-14 ?M) and primary production was low (153-310 mgC m -2 d -1), suggesting that reduced light radiation depressed the plankton dynamics throughout Moraleda Channel. In spring, primary production followed a conspicuous N-S gradient, which was the highest (5167 mgC m -2 d -1) in the north microbasin and the lowest (742 mgC m -2 d -1) in the south microbasin. The seasonal pattern of the semi-enclosed Puyuhuapi Channel and Aysen Fjord, however, revealed no significant differences in primary production (˜800 mgC m -2 d -1), and vertical fluxes of particulate organic carbon were nearly twice as high in spring as in winter (266 vs. 168 mgC m -2 d -1). At the time-series station (St. 79), the lithogenic fraction dominated the total sedimented matter (seston). The role of euphausiids in the biological carbon pump of the Patagonian fjords was evident, given the predominance of zooplankton fecal material, mostly euphausiid fecal strings (46% of all fecal material), among the recognizable particles contributing to the particulate organic carbon flux. The topographic constriction sills partially modulated the exchange of oceanic waters (Subantarctic Surface Water) with freshwater river discharges along the Moraleda Channel. This exchange affects salinity and nutrient availability and, thus, the plankton structure. The north microbasin was dominated by a seasonal alternation of the classical (spring) and microbial (winter) food webs. However, in the south microbasin, productivity was low and the system was dominated year-round by large inputs of glacier-derived, silt-rich freshwater carrying predominantly small-sized diatoms ( Skeletonema spp) and bacteria. When superimposed upon this scenario, highly variable (seasonal) solar radiation and photoperiods could exacerbate north-south differences along Moraleda Channel.

González, H. E.; Castro, L.; Daneri, G.; Iriarte, J. L.; Silva, N.; Vargas, C. A.; Giesecke, R.; Sánchez, N.

2011-03-01

39

Late Paleozoic to Early Jurassic tectonic development of the high Andean Principal Cordillera, El Indio Region, Chile (29 30°S)  

NASA Astrophysics Data System (ADS)

Regional mapping (1:50,000) and U-Pb and K-Ar geochronology in the El Indio region refines the knowledge of the distribution, lithostratigraphy, and age of the sedimentary, volcanic, and intrusive rocks that comprise the regionally extensive Pastos Blancos Group which is equivalent to the Choiyoi Group of the Argentine Frontal Cordillera. The Pastos Blancos Group (which we elevate to Group status herein) includes at least two diachronous volcanic-sedimentary sequences: an older felsic volcanic and volcaniclastic unit, the Guanaco Sonso sequence, that is Permian in age, and a younger bimodal volcanic and volcaniclastic unit, the Los Tilos sequence that is Middle Triassic to Early Jurassic. Sedimentary rocks of the Los Tilos sequence are transitional upward into the overlying Early to Middle Jurassic shallow marine limestones of the Lautaro Formation. Intrusions that make up the regionally extensive Permian to Early Jurassic plutons of the Chollay and Elqui-Limar?´ batholiths that were previously mapped as a single plutonic association, the Ingaguás Complex, include in the El Indio region at least three discrete intrusive units. These include: Early Permian (280-270 Ma) biotite granites, Early to Middle Triassic (242-238 Ma) silica-rich leucocratic granites and rhyolitic porphyries that made up the bulk of the Chollay Batholith, and a younger Late Triassic-Early Jurassic unit (221-200 Ma) of mainly intrusive rhyolitic porphyries, extrusive domes, and subordinate mafic intrusions and both felsic and mafic dikes, which are coeval with volcanic rocks of the Los Tilos sequence. Our data show that latest Paleozoic to Early Jurassic intrusive, volcanic, and sedimentary rocks in the El Indio region of the High Andes of Chile between 29-30°S likely formed during extension driven processes after the cessation of Carboniferous-Early Permian subduction along the western edge of Gondwana. These processes began by Late Permian time, but instead of recording a single and protracted magmatic event, as has been previously suggested, rocks that belong to the Pastos Blancos Group and the Ingaguás Intrusive Complex record at least three discrete periods of silicic to bimodal magmatism which occurred during the Middle Permian to Early Jurassic interval.

Martin, Mark W.; Clavero R, Jorge; Mpodozis M, Constantino

1999-01-01

40

Possible structures of the old Urcunina Caldera, revealed by high precision relocation of VT earthquakes at Galeras volcano  

NASA Astrophysics Data System (ADS)

Volcano-Tectonic earthquakes at Galeras Volcano were relocated using the waveform catalog waveform and preliminary phase arrival data compiled by the monitoring network at Observatorio Volcanológico y Sismológico de Pasto. Several routines were developed in MATLAB, mainly to prepare waveforms, calculate differential travel times, and identifying seismic families; and the HypoDD program was implemented, which allowed performing the relocations. The procedure resulted in the detection of 10 swarm-type families and 4 spatial-type families of earthquakes, which reveal a fault of 1.6 km bounding the Urcunina Caldera, and a ring fault of 1.8 km in diameter, adjacent to the crater. Reductions in the range 56.84% - 87.48% were achieved in the hypocentral parameters uncertainties as compared to uncertainties in traditional locations, to finally obtain an alternative image of the Volcano-Tectonic earthquakes distribution Galeras Volcano VG with a significantly lower uncertainty.

Lizarazo C, M. J.; Alvarado, H.; Sanchez, J. J.

2013-12-01

41

Serologic evidence that Ascaris and Toxoplasma infections impact inflammatory responses to Helicobacter pylori in Colombians  

PubMed Central

Background Helicobacter pylori infected children from coastal Tumaco, Colombia have more parasitism, and adults have lower gastric cancer risk compared to high altitude Pasto/Tuquerres residents. Because helminth and Toxoplasma gondii infections alter helicobacter gastritis in rodent models, we determined if seropositivity to Ascaris lumbricoides or T. gondii was associated with Th2-IgG1 or Th1-IgG2 responses to H. pylori. Methods Sera (240) from the two populations were evaluated for A. lumbricoides and T. gondii seropositivity and results correlated with IgE and IgG isotype responses to H. pylori. Results Most Tumaco children and adults were seropositive for A. lumbricoides (89%, 66%), T. gondii (59%, 98%) or both (45%, 66%). In contrast, seropositivity among Pasto/Tuquerres children was much lower (9% A. lumbricoides, 11% T. gondii and 2% dual positive) but increased in adults (58% A. lumbricoides, 82% T. gondii and 41% dual positive). A. lumbricoides seropositivity correlated with elevated IgE and anti-inflammatory Th2-IgG1 responses to H. pylori, while Toxoplasma gondii seropositivity was linked to elevated IgE, pro-inflammatory Th1-IgG2, IgG3 and IgG4 responses to H. pylori. Individuals with high T. gondii titers had reduced Th1-IgG2, IgG3 and IgG4 responses to Helicobacter pylori. Conclusions Results support regional differences for childhood parasitism and indicate A. lumbricoides and T. gondii infections may impact inflammatory responses to H. pylori and partially explain differences in gastric cancer risk in Colombia. PMID:22404440

Ek, Courtney; Whary, Mark T.; Ihrig, Melanie; Bravo, Luis E.; Correa, Pelayo; Fox, James G.

2011-01-01

42

Study of the Comet C/2013 A1 (Siding Spring)  

NASA Astrophysics Data System (ADS)

The comet called C/2013 A1 (SIDING SPRING) was discovered on January 3, 2013 in Australia. In January 28/2014, NASA announced that is preparing for the close encounter that will happen between the comet C/2013 A1 and Mars on October 19-2014. The Mission called “MAVEN” will insert in Mars orbit on september 21—2014. The comet will pass just 138,000 kilometers far from the surface of Mars. The probability that the comet collides with Mars is small but the dust particles emitted by the comet can cause damage to spacecrafts and probes that are in orbit around that planet. NASA is making preparations to take all precautions. If the comet is quite active, there will be almost no time to take security measures with Mars orbiters. For that reason NASA is already ahead of the facts. According to scientists of the "JET PROPULSION LABORATORY-JPL", dust particles spewing from the comet may be traveling at 56 km / sec in relation to the orbiters, fifty times faster than the speed of a bullet. From our Observatory, located in Pasto-Colombia, we captured several pictures, videos and astrometry data during several days. The pictures of the asteroid were captured with the following equipment: CGE PRO 1400 CELESTRON (f/11 Schmidt-Cassegrain Telescope) and STL-1001 SBIG camera. Astrometry was carried out, and we calculated the orbital elements.Summary And Conclusions: We obtained the following orbital parameters: eccentricity = 1.0003983, orbital inclination = 129.03078 deg, longitude of the ascending node = 300.99538 deg, argument of perihelion = 2.42310 deg, perihelion distance = 1.40023196 A.U. The parameters were calculated based on 20 observations (Jan 21 to April 02) with mean residual = 0.334 arcseconds. We also obtained the light curve of the body with our data (January to November/2014)Acknowledgements: The authors would like to thank to University of Narino-Pasto-Colombia.

Vodniza, Alberto Q.; Pereira, Mario R.

2014-11-01

43

Management of pest mole crickets in Florida and Puerto Rico with a nematode and parasitic wasp  

SciTech Connect

Non-indigenous invasive mole crickets, Scapteriscus vicinus Scudder (Orthoptera: Gryllotalpidae) in Florida and S. didactylus (Latreille) (the 'changa') in Puerto Rico, are being managed with an entomopathogenic nematode, Steinernema scapterisci (Nguyen and Smart) (Rhabditida: Steinernematidae), and a parasitic wasp, Larra bicolor L. (Hymenoptera: Sphecidae). Pest mole cricket populations have declined by 95% in north central Florida since these specialist natural enemies were released and established in the 1980s. Commercial production of the nematode was initiated, nearly 70 billion were applied in 34 Florida counties, and their establishment, spread, and impact on mole crickets were monitored. The infected mole crickets dispersed the nematode rapidly, so that within 6 months these parasites were present in most of the insects trapped in experimental pastures. Three years later, mole cricket populations were reduced to acceptable levels and the bahiagrass had recovered. The nematode was released for the first time in Puerto Rico during 2001 and has persisted; the wasp was introduced in the late 1930s. The geographical distribution of the wasp is being expanded in Florida and Puerto Rico by planting plots of Spermacoce verticillata (L.), a wildflower indigenous to Puerto Rico and widely distributed in southern Florida. Pastures, sod farms, golf courses, landscapes, and vegetable farms in Florida and Puerto Rico are benefiting from biological control of invasive mole crickets. (author) [Spanish] Los grillotopos invasores no indigenas, Scapteriscus vicinus (Orthoptera: Gryllotalpidae) en el estado de Florida y S. didactylus ('changa') en Puerto Rico, estan siendo manejados por el nematodo entomopathogeno, Steinernema scapterisci (Rhabditida: Steinernematidae) y la avispa parasitica, Larra bicolor (Hymenoptera: Sphecidae). Las poblaciones de los grillotopo plagas han declinado un 95% en el norte central de la Florida desde que estos enemigos naturales especialistas fueron liberados y establecidos en los 80s. Consecuentemente, la produccion comercial del nematodo fue iniciada, casi 70 billones fueron aplicados en 34 condados de la Florida, y se realizo un monitoreo para evaluar su establecimiento, dispersion e impacto sobre los grillotopos. Los gillotopos infectados dispersaron los nematodos rapidamente, tanto que despues de 6 meses estos parasitos estaban presentes en la mayoria de los insectos atrapados en los pastos experimentales. Tres anos despues, las poblaciones de los grillotopos fueron reducidas a niveles aceptables y los campos de pasto 'bahia' se recuperaron. El nematodo fue liberado para la primera vez en Puerto Rico durante del 2001 y ha persistido; la avispa fue introducida al final de los 30s. La distribucion geografica de la avispa se esta extendiendo en la Florida y Puerto Rico por medio de la siembra de parcelas de Spermacoce verticillata, una flor silvestre indigena a Puerto Rico y distribuida ampliamente en el sur de la Florida. Los campos de pasto, las operaciones comerciales de cesped, los campos de golf, los paisajes y las fincas de hortalizas en la Florida y Puerto Rico se estan beneficiando del control biologico de los grillotopos invasores. (author)

Leppla, N.C.; Frank, J.H. [University of Florida, Institute of Food and Agricultural Sciences, Department of Entomology and Nematology, P.O. Box 110630, Gainesville, FL 32611-0630 (United States); Adjei, M.B. [University of Florida, Range Cattle Research and Education Center, 3401 Experiment Station, Ona, FL 33865-9706 (United States); Vicente, N.E. [University of Puerto Rico, Agricultural Experiment Station, P.O. Box 9030, Mayaguez, PR 00681-9030 (Puerto Rico)

2007-03-15

44

A sustainability model based on cloud infrastructures for core and downstream Copernicus services  

NASA Astrophysics Data System (ADS)

The incoming Sentinel missions have been designed to be the first remote sensing satellite system devoted to operational services. In particular, the Synthetic Aperture Radar (SAR) Sentinel-1 sensor, dedicated to globally acquire over land in the interferometric mode, guarantees an unprecedented capability to investigate and monitor the Earth surface deformations related to natural and man-made hazards. Thanks to the global coverage strategy and 12-day revisit time, jointly with the free and open access data policy, such a system will allow an extensive application of Differential Interferometric SAR (DInSAR) techniques. In such a framework, European Commission has been funding several projects through the GMES and Copernicus programs, aimed at preparing the user community to the operational and extensive use of Sentinel-1 products for risk mitigation and management purposes. Among them, the FP7-DORIS, an advanced GMES downstream service coordinated by Italian National Council of Research (CNR), is based on the fully exploitation of advanced DInSAR products in landslides and subsidence contexts. In particular, the DORIS project (www.doris-project.eu) has developed innovative scientific techniques and methodologies to support Civil Protection Authorities (CPA) during the pre-event, event, and post-event phases of the risk management cycle. Nonetheless, the huge data stream expected from the Sentinel-1 satellite may jeopardize the effective use of such data in emergency response and security scenarios. This potential bottleneck can be properly overcome through the development of modern infrastructures, able to efficiently provide computing resources as well as advanced services for big data management, processing and dissemination. In this framework, CNR and ESA have tightened up a cooperation to foster the use of GRID and cloud computing platforms for remote sensing data processing, and to make available to a large audience advanced and innovative tools for DInSAR products generation and exploitation. In particular, CNR is porting the multi-temporal DInSAR technique referred to as Small Baseline Subset (SBAS) into the ESA G-POD (Grid Processing On Demand) and CIOP (Cloud Computing Operational Pilot) platforms (Elefante et al., 2013) within the SuperSites Exploitation Platform (SSEP) project, which aim is contributing to the development of an ecosystem for big geo-data processing and dissemination. This work focuses on presenting the main results that have been achieved by the DORIS project concerning the use of advanced DInSAR products for supporting CPA during the risk management cycle. Furthermore, based on the DORIS experience, a sustainability model for Core and Downstream Copernicus services based on the effective exploitation of cloud platforms is proposed. In this framework, remote sensing community, both service providers and users, can significantly benefit from the Helix Nebula-The Science Cloud initiative, created by European scientific institutions, agencies, SMEs and enterprises to pave the way for the development and exploitation of a cloud computing infrastructure for science. REFERENCES Elefante, S., Imperatore, P. , Zinno, I., M. Manunta, E. Mathot, F. Brito, J. Farres, W. Lengert, R. Lanari, F. Casu, 2013, "SBAS-DINSAR Time series generation on cloud computing platforms". IEEE IGARSS Conference, Melbourne (AU), July 2013.

Manunta, Michele; Calò, Fabiana; De Luca, Claudio; Elefante, Stefano; Farres, Jordi; Guzzetti, Fausto; Imperatore, Pasquale; Lanari, Riccardo; Lengert, Wolfgang; Zinno, Ivana; Casu, Francesco

2014-05-01

45

The Parallel SBAS-DInSAR algorithm: an effective and scalable tool for Earth's surface displacement retrieval  

NASA Astrophysics Data System (ADS)

Differential Synthetic Aperture Radar Interferometry (DInSAR) is an effective technique to estimate and monitor ground displacements with centimetre accuracy [1]. In the last decade, advanced DInSAR algorithms, such as the Small Baseline Subset (SBAS) [2] one that is aimed at following the temporal evolution of the ground deformation, showed to be significantly useful remote sensing tools for the geoscience communities as well as for those related to hazard monitoring and risk mitigation. DInSAR scenario is currently characterized by the large and steady increasing availability of huge SAR data archives that have a broad range of diversified features according to the characteristics of the employed sensor. Indeed, besides the old generation sensors, that include ERS, ENVISAT and RADARSAT systems, the new X-band generation constellations, such as COSMO-SkyMed and TerraSAR-X, have permitted an overall study of ground deformations with an unprecedented detail thanks to their improved spatial resolution and reduced revisit time. Furthermore, the incoming ESA Sentinel-1 SAR satellite is characterized by a global coverage acquisition strategy and 12-day revisit time and, therefore, will further contribute to improve deformation analyses and monitoring capabilities. However, in this context, the capability to process such huge SAR data archives is strongly limited by the existing DInSAR algorithms, which are not specifically designed to exploit modern high performance computational infrastructures (e.g. cluster, grid and cloud computing platforms). The goal of this paper is to present a Parallel version of the SBAS algorithm (P-SBAS) which is based on a dual-level parallelization approach and embraces combined parallel strategies [3], [4]. A detailed description of the P-SBAS algorithm will be provided together with a scalability analysis focused on studying its performances. In particular, a P-SBAS scalability analysis with respect to the number of exploited CPUs has been carried out on real data acquired by ENVISAT and COSMO-SkyMed sensors. Moreover, the P-SBAS performances with respect to the size of the input dataset will also be investigated. This kind of analysis is essential for assessing the goodness of the P-SBAS algorithm and gaining insight into its applicability to different scenarios. Besides, such results will also become crucial to identify and evaluate how to appropriately exploit P-SBAS to process the forthcoming large Sentinel-1 data stream. References [1] Massonnet, D., Briole, P., Arnaud, A., "Deflation of Mount Etna monitored by Spaceborne Radar Interferometry", Nature, vol. 375, pp. 567-570, 1995. [2] Berardino, P., G. Fornaro, R. Lanari, and E. Sansosti, "A new algorithm for surface deformation monitoring based on small baseline differential SAR interferograms", IEEE Trans. Geosci. Remote Sens., vol. 40, no. 11, pp. 2375-2383, Nov. 2002. [3] Elefante, S., Imperatore, P. , Zinno, I., M. Manunta, E. Mathot, F. Brito, J. Farres, W. Lengert, R. Lanari, F. Casu, "SBAS-DINSAR Time series generation on cloud computing platforms", IEEE IGARSS 2013, July 2013, Melbourne (AU). [4] Zinno, P. Imperatore, S. Elefante, F. Casu, M. Manunta, E. Mathot, F. Brito, J. Farres, W. Lengert, R. Lanari, "A Novel Parallel Computational Framework for Processing Large INSAR Data Sets", Living Planet Symposium 2013, Sept. 9-13, 2013.

Zinno, Ivana; De Luca, Claudio; Elefante, Stefano; Imperatore, Pasquale; Manunta, Michele; Casu, Francesco

2014-05-01

46

Distribution of a Community of Mammals in Relation to Roads and Other Human Disturbances in Gabon, Central Africa  

PubMed Central

Abstract We present the first community-level study of the associations of both roads and other human disturbances with the distribution of mammals in Gabon (central Africa). Our study site was in an oil concession within a littoral mosaic landscape. We conducted surveys along 199 line transects and installed camera traps on 99 of these transects to document mammal presence and abundance. We used generalized linear mixed-effect models to document associations between variables related to the ecosystem (land cover, topography, and hydrology), roads (coating, width of rights of way, condition, type of vehicle used on the road, traffic level, affiliation of users, and general type of road), and other human disturbances (urbanization, agriculture, hunting, logging, gathering, and industrial activities) and the abundance or presence of 17 species or groups of mammals including elephant (Loxodonta cyclotis), buffalo (Syncerus caffer), sitatunga (Tragelaphus spekei), red river hog (Potamochoerus porcus), smaller ungulates, gorilla (Gorilla gorilla), chimpanzee (Pan troglodytes), side-striped jackal (Canis adustus), carnivores, monkeys, and large rodents. Some types of roads and other human disturbances were negatively associated with the abundance or presence of elephants, buffalos, gorillas, sitatungas, some monkeys, and duikers. The pattern of associations of mammals with roads and other human disturbances was diverse and included positive associations with road presence (red river hog, some monkeys, and duikers), agriculture (sitatunga, small carnivores, and large rodents) and industrial activities (sitatunga, red river hog, red duikers, and side-striped jackal). Our results suggest that the community of mammals we studied was mostly affected by hunting, agriculture, and urbanization, which are facilitated by road presence. We recommend increased regulation of agriculture, hunting, and road building in the area. Distribución de una Comunidad de Mamíferos en Relación a Carreteras y Otras Perturbaciones Humanas en Gabón, Africa Central Resumen Presentamos el primer estudio a nivel de comunidad de la relación entre carreteras y otras perturbaciones humanas con la distribución de mamíferos en Gabón (África central). Nuestro sitio de estudio está dentro de una concesión petrolera en un paisaje litoral heterogéneo. Realizamos muestreos a lo largo de 199 transectos lineales e instalamos cámaras trampa en 99 de ellos para documentar la presencia y abundancia de mamíferos. Utilizamos modelos lineales generalizados con efectos mixtos para documentar las asociaciones entre variables relacionadas con el ecosistema (cobertura de suelo, topografía e hidrología), carreteras (tipo de revestimiento, ancho de derecho de vía, condición, tipo de vehículos que utilizan la carretera, nivel de tráfico, afiliación de los usuarios y el tipo general de carretera) y otras perturbaciones humanas (urbanización, agricultura, caza, tala, recolecta y actividades industriales) y la abundancia o presencia de 17 especies o grupos de mamíferos incluyendo elefantes (Loxodonta cyclotis), búfalo (Syncerus caffer), sitatunga (Tragelaphus spekei), cerdo rojo de río (Potomochoerus porcus), ungulados pequeños, gorila (Gorilla gorilla), chimpancé (Pan troglodytes), chacal con rayas a los lados (Canis adustus), carnívoros, monos y roedores de talla grande. Ciertos tipos de carreteras y otras perturbaciones humanas estuvieron asociadas negativamente con la abundancia o presencia de elefantes, búfalos, gorilas, sitatungas, algunos monos y antílopes. Los patrones de asociación de mamíferos con carreteras y otras perturbaciones humanas fueron diversos e incluyen asociaciones positivas con la presencia de carreteras (cerdo rojo de río, algunos monos y antílopes), agricultura (sitatunga, carnívoros pequeños y roedores de talla grande) y actividades industriales (sitatunga, cerdo rojo de río, a

Vanthomme, Hadrien; Kolowski, Joseph; Korte, Lisa; Alonso, Alfonso

2013-01-01

47

14C ages and activity for the past 50 ka at Volca??n Galeras, Colombia  

USGS Publications Warehouse

Volca??n Galeras is the southernmost Colombian volcano with well-recorded historic activity. The volcano is part of a large and complex volcanic center upon which 400,000 people live. Historic activity has centered on a small-volume cone inside the youngest of several large amphitheaters that breach the west flank of the volcano, away from the city of Pasto (population 300,000). Lava flows (SiO2 between 54.6 and 64.7 wt.%) have dominated activity for more than 1 Ma, but explosive events have also occurred. Joint studies by volcanologists from Colombia, Ecuador, Peru, Bolivia, Argentina, and the United States produced 24 new 14C ages and more than 100 stratigraphic sections to interpret the past 50 ka of activity at Galeras, including sector collapse events. The youngest collapse event truncated 12.8 ka lava flows and may have occurred as recently as 8 to 10 ka. Tephra-fall material rapidly thins and becomes finer away from the vent area. The only widespread marker in the < 10 ka section is a biotite-bearing tephra deposited between 4.1 and 4.5 ka from a source south of Galeras. It separates cryoturbated from largely undisturbed layers on Galeras, and thus dates a stratigraphic horizon which is useful in the interpretation of other volcanoes and geotectonics in the equatorial Andes. Pyroclastic flows during the past 50 ka have been small to moderate in volume, but they have left numerous thin deposits on the north and east flanks where lava flows have been impeded by crater and amphitheater walls. Many of the pyroclastic-flow deposits are lithic rich, with fines and clasts so strongly altered by hydrothermal action before eruption that they, as well as the sector collapse deposits, resemble waste dumps of leached cappings from disseminated sulfide deposits more than volcanogenic deposits. This evidence of a long-lived hydrothermal system indicates susceptibility to mass failure and explosive events higher than expected for a volcano built largely by lava flows and modest Vulcanian eruptions. Photographs, written accounts, and our study document historic north and east flank pyroclastic flows as far as 10 km from the summit; however, none have left recognizable deposits in Pasto for more than 40 ka.

Banks, N.G.; Calvache, V.M.L.; Williams, S.N.

1997-01-01

48

Human occupation of Iberia prior to the Jaramillo magnetochron (>1.07 Myr)  

NASA Astrophysics Data System (ADS)

The first migration out of Africa undertaken by the genus Homo is documented in Georgia at 1.8 Myr (Dmanisi) and some 0.4 Myr afterwards in the Middle East ('Ubeidiya). However, the debate on when the European continent was populated for the first time remains open. The first human presence in Europe prior to the Jaramillo subchron (1.07-0.99 Myr) is evidenced at Fuente Nueva 3 and Barranco León D (Orce) and at Sima del Elefante (Atapuerca), an occupation that seems to have continued through the Jaramillo at Gran Dolina TD3-4 and TD5 (Atapuerca), at Vallparadís (Barcelona), and up to the Matuyama-Brunhes boundary at Gran Dolina TD6. Even so, those who still defend a ‘short chronology' espouse an intermittent early population limited to the Mediterranean area, delaying the first occupation until after the Jaramillo. These hypotheses fail to explain what factors were behind the absence of population in Europe prior to this period, bearing in mind that there were populations of hominins at the gates of Europe between 1 and 0.5 Myr before the first archaeological record documented in Western Europe. Paleomagnetic analyses of the archaeological sites are rarely able to detect the Jaramillo subchron due to its short duration, while the radiometric dating methods (U-series/ESR) usually applied are limited in the accuracy they can achieve for the chronologies in question. These limitations make it necessary to depend on the biostratigraphy of small and large mammals to ascertain with precision the time of the first colonization of the continent. Accordingly, in the present article we discuss the chronological data from the older Iberian archaeological sites using biostratigraphic data to establish an archaeological sequence that demonstrates the expansion of the first hominin occupation of Southern Europe prior to Jaramillo.

Garcia, Joan; Martínez, Kenneth; Cuenca-Bescós, Gloria; Carbonell, Eudald

2014-08-01

49

Legal ivory trade in a corrupt world and its impact on African elephant populations.  

PubMed

Illegal hunting of African elephants (Loxodonta africana) for ivory is causing rapid declines in their populations. Since 2007, illegal ivory trade has more than doubled. African elephants are facing the most serious conservation crisis since 1989, when international trade was banned. One solution proposed is establishment of a controlled legal trade in ivory. High prices for ivory mean that the incentives to obtain large quantities are high, but the quantity of tusks available for trade are biologically constrained. Within that context, effective management of a legal ivory trade would require robust systems to be in place to ensure that ivory from illegally killed elephants cannot be laundered into a legal market. At present, that is not feasible due to corruption among government officials charged with implementing wildlife-related legislation. With organized criminal enterprises involved along the whole commodity chain, corruption enables the laundering of illegal ivory into legal or potentially legal markets. Poachers and traffickers can rapidly pay their way out of trouble, so the financial incentives to break the law heavily outweigh those of abiding by it. Maintaining reliable permitting systems and leak-proof chains of custody in this context is challenging, and effective management breaks down. Once illegal ivory has entered the legal trade, it is difficult or impossible for enforcement officers to know what is legal and illegal. Addressing corruption throughout a trade network that permeates countries across the globe will take decades, if it can ever be achieved. That will be too late for wild African elephants at current rates of loss. If we are to conserve remaining wild populations, we must close all markets because, under current levels of corruption, they cannot be controlled in a way that does not provide opportunities for illegal ivory being laundered into legal markets. Comercio Legal de Marfil en un Mundo Corrupto y su Imapacto sobre Poblaciones de Elefantes. PMID:25103555

Bennett, Elizabeth L

2015-02-01

50

A warning bell? Tornillo events at Galeras Volcano, Colombia  

NASA Astrophysics Data System (ADS)

In 1993, five of the six ash eruptions at Galeras Volcano, Colombia were preceded by distinctive seismic events, called tornillos. These unusual tremor wavelets have quasi-sinusoidal waveforms with screw-like envelope profiles and can last up to several minutes. Since December 1990, more than 60 of these events have been recorded at Galeras Volcano. As a class, they appear to be more complex than those previously recorded with the broadband instruments or with the shortperiod network of the Observatorio Vulcanológico y Sismológico in Pasto. They are multichromatic with a varying number of spectral peaks between 1 and up to 50 Hz. The peaks for frequencies which extend into the coda are extremely narrow, while those present only during the initial excitation are relatively broad. We parameterize the tornillo signals in the time and frequency domains, examining differences in the two classes of spectral peaks, and derive distribution and correlation functions for signal parameters such as frequency, Q, energy, and polarization. We investigate variations in these parameters with regard to ash eruptions during the past 3 years. In addition, we use the parameters along with the signal signature to derive qualitative conclusions about possible underlying processes and excitation mechanisms and to provide constraints for modelling variations of the source process, as, for example, a cavity resonator. For example, the distribution of frequencies for the suite of tornillos appears to be discrete below 6 Hz and a continuum above, as would be expected for a cavity.

Hellweg, M.; Seidl, D.

2003-12-01

51

Residents, Decision Makers, and Scientists Discuss Volcanic Hazard in Colombia  

NASA Astrophysics Data System (ADS)

Knowledge Sharing and Collaboration in Volcanic Risk Mitigation at Galeras Volcano, Colombia; Pasto, Colombia, 6-11 July 2009; Galeras volcano, located in southwestern Colombia, imposes several hazards on the surrounding population: pyroclastic flows, lahars, ashfall, and shock waves. The current hazard map shows three zones: high, medium, and low (see A. D. Hurtado Artunduaga and G. P. Cortés Jiménez, J. Volcanol. Geotherm. Res., 77, 89-100, 1997). The pyroclastic flow hazard on this map defines the Zone of High Volcanic Hazard (ZAVA) for civil authorities. Current activity of Galeras has provoked two contentious issues related to hazard management: (1) Decision makers announce an evacuation order of ZAVA whenever the volcanic alert reaches a high level, and (2) the Colombian government initiated a relocation program for the inhabitants within ZAVA (Colombian Decrees-Laws 4106 and 3905). However, communities within ZAVA refuse to obey both the evacuation orders and the relocation process. To help resolve this situation, the University of Nariño (Colombia) and the State University of New York at Buffalo organized a workshop, which was sponsored by the U.S. National Science Foundation. A daily average of 92 people attended, including residents of ZAVA, decision makers, Colombian technical and scientific personnel, international scientists and researchers, students, and academics from the University of Nariño.

Sheridan, Michael F.; Cordoba, Gustavo

2010-02-01

52

[Detection and molecular characterization of Potato virus S (PVS, Carlavirus) from Colombia].  

PubMed

In Colombia, potato crops are affected by a wide variety of viruses such as PVY, PLRV, PVX, PMTV and PVS. Unfortunately, there are very few studies on the biology, distribution and pathogenicity of these viruses; this situation is even worse for the latent virus PVS. In this work, we evaluated the presence ofPVS in four Colombian provinces (Antioquia, Boyacá, Cundinamarca, Nariño) by the use of ELISA. We also studied the degree of molecular variation by sequence comparison of a segment of the gene encoding for the viral coat protein. In average, PVS was detected in 40% of 320 analyzed samples of potato leaves; the highest levels were observed in the East ofAntioquia (49%) and Pasto (Nariño) (47%), while in the other regions ranged between 35% and 42%. Analysis of sequence revealed the presence of two PVS strains in Colombia: three isolates were associated to PVSo (Ordinary) and twelve belonged to PVSA (Andean). A high diversity was observed among PVSA strains with percent identities in the range of 88-99%. These findings highlight the importance of strengthening seed certification programs and quarantine measures in Colombia for viruses like PVS, which can cause losses of up to 20% in potato crops and even higher in mixed virus infection. PMID:23885575

Fernando, Gil José; Cotes, José Miguel; Marín, Mauricio

2013-06-01

53

Galeras Volcano: International Workshop and Eruption  

NASA Astrophysics Data System (ADS)

Galeras, a 4270-m high andesitic stratovolcano in southwestern Colombia near the Ecuadorian border (Figure 1), gradually reawoke in 1988 after more than 40 years of dormancy. In 1991, after a request from the Geological Survey of Colombia (INGEOMIAS) and the National Disaster Prevention Office (ONAD), Galeras was named a “Decade Volcano” by the International Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI) as part of the United Nations' International Decade for Natural Disaster Reduction (IDNDR) program. A workshop was held in 1993 to research, monitor, and mitigate the hazards of the volcano.Galeras lies at latitude 1°14?N, longitude 77°22?W (see Figure 2), and its active cone rises about 150 m above the floor of a small summit caldera that is open to the west [Calvache and Williams, 1992]. The active crater is located about 6 km west of Pasto, a city of about 300,000 inhabitants. At least six major Galeras eruptions have been identified during the past 4500 years. These eruptions were mainly vulcanian, with inferred low-altitude eruption columns (<10 km) that produced small-volume pyroclastic flow deposits containing a high proportion of nonjuvenile material and lava flow fragments [Calvache and Williams, 1992]. During the last 500 years, eruptions have been characterized by gas and ash emissions, small lava flows, and explosive eruptions producing pyroclastic flows that have traveled up to 15 km from the crater [Calvache, 1990; Cepeda, 1993].

Muñoz, F. A.; Calvache, M. L.; Cortes, G. P.; Gomez, D. M.; Narvaez, L.; Ordonez, M.; Ortega, A.; Torres, R.; Silva, B.; Williams, S. N.; Sanders, C. O.; Stix, J.

54

Post-Gondwanan continental sedimentaiton, Limpopo region, southeastern Africa  

NASA Astrophysics Data System (ADS)

The post-Karoo age sedimentary succession known formerly as the Malvernia Formation, is currently termed the Malonga Formation, 'Formaçao de Sena', 'Formaçao de Singuédeze/Elefantes' and Gona-re-Zhou Plateau Beds in the Limpopo Basin region where South Africa, Mozambique and Zimbabwe have common borders. These rocks represent continental, taphrogenic sedimentation on the eastern margin of the emergent African continent after the breakup of Gondwana. The wide occurrence of this system along the northern Lebombo mountains and within the tectonically active Limpopo and Zambezi valleys, suggests the existence of a peidmont landsurface comprising coalesced alluvial fans and major fluvial channel/floodplain systems close to the continental margin during the Late Mesozoic to Early Cainozoic era. Sedimentation followed the long period of eustatic uplift associated with Karoo vulcanicity and the extensional tectonics and rifting along the continental margin and within the proto-Limpopo and Zambezi valleys. The Malonga Formation exposed near Pafuri in the extreme NW of South Africa shows an eastward lithological change from homogeneous, poorly-sorted, thinly-bedded sandstones and conglomerates, deposited by sheetflood action, to a sequence of fining-upward units comprising clast-supported pebble to boulder grade conglomerate and overlying planar bedded silt and sand, deposited in fluvial channel and floodplain environments. The homogeneous, silty succession exposed in the Olifants River valley, east of the Lebombo mountains in Mozambique, possibly represents the distal reaches of this system. Calcareous palaeosols developed within the sedimentary units suggest periodic geomorphic stability on the broad alluvial plain. Further north in southeastern Zimbabwe, laterally continuous depositional units comprising thinly-bedded, poorly-sorted, matrix-supported conglomerate, interbedded with very coarse-grained sandstone, is consistent with deposition on an alluvial fan complex generated off areas of high relief bedrock topography. The initiation of this period of sedimentation is poorly constrained, and one must look to continental/marine stratigraphic relationships below the Mozambique coastal plain and in the Zambezi valley for an indication of the maximum and minimum ages. The most commonly accepted period of accumulation is during the Middle to Late Cretaceous. Deposition apparently ceased during the Late Cretaceous with the formation of the thick silcrete layer associated with the 'African' landsurface during this long period of geomorphic stability prior to the Palaeocene. The Eocene marine transgression resulted in truncation of the Malonga Formation and deposition of littoral and estuarine sediments high against the Lebombo mountains.

Botha, G. A.; De Wit, M. C. J.

1996-08-01

55

Continuity or discontinuity in the European Early Pleistocene human settlement: the Atapuerca evidence  

NASA Astrophysics Data System (ADS)

The nature, timing, pattern, favourable circumstances and impediments of the human occupation of the European continent during the Early Pleistocene are hot topics in Quaternary studies. In particular, the problem of the (dis) continuity of the settlement of Europe in this period is an important matter of discussion, which has been approached in the last decade from different points of view. The Gran Dolina (TD) and Sima del Elefante (TE) cave sites in the Sierra de Atapuerca, (Spain) include large and quasi-continuous stratigraphic sequences that stretch back from at least 1.2 million years ago (Ma) to the Matuyama/Brunhes boundary. The archaeological and paleontological record from these sites can help to test different hypotheses about the character of the human settlement in this region and period. Furthermore, the TD6 level has yielded a large collection of human fossil remains attributed to Homo antecessor. According to different geochronological methods, as well as to paleomagnetic and biostratigraphical analyses, these hominins belong to an age range of 0.96-0.80 Ma. Unfortunately, the finding in 2007 of some human fossil remains in the TE9 level, dated to about 1.22 Ma, was not enough to conclude whether H. antecessor had deep roots in the European Early Pleistocene. A set of derived features of H. antecessor shared with both the Neanderthal lineage and modern humans suggests that this species is related, and not far, from the most recent common ancestor (MRCA) of Homo neanderthalensis and Homo sapiens. If we assume that there was a lineal biological relationship between the TE9 and TD6 hominins, we should reconsider many of the conclusions achieved in previous paleontological and genetic studies. In addition, we would be obliged to build a highly complicated paleogeographical scenario for the origin of the MRCA. Although continuity in the settlement of Europe during the entire late Early Pleistocene is not discarded (e.g. in refuge areas), it seems that this Western extreme of Eurasia, and the Iberian Peninsula in particular, was occupied by at least two different hominin populations.

Bermúdez de Castro, José María; Martinón-Torres, María; Blasco, Ruth; Rosell, Jordi; Carbonell, Eudald

2013-09-01

56

New luminescence ages for the Galería Complex archaeological site: resolving chronological uncertainties on the acheulean record of the Sierra de Atapuerca, northern Spain.  

PubMed

The archaeological karstic infill site of Galería Complex, located within the Atapuerca system (Spain), has produced a large faunal and archaeological record (Homo sp. aff. heidelbergensis fossils and Mode II lithic artefacts) belonging to the Middle Pleistocene. Extended-range luminescence dating techniques, namely post-infrared infrared stimulated luminescence (pIR-IR) dating of K-feldspars and thermally transferred optically stimulated luminescence (TT-OSL) dating of individual quartz grains, were applied to fossil-bearing sediments at Galería. The luminescence dating results are in good agreement with published chronologies derived using alternative radiometric dating methods (i.e., ESR and U-series dating of bracketing speleothems and combined ESR/U-series dating of herbivore teeth), as well as biochronology and palaeoenvironmental reconstructions inferred from proxy records (e.g., pollen data). For the majority of samples dated, however, the new luminescence ages are significantly (?50%) younger than previously published polymineral thermoluminescence (TL) chronologies, suggesting that the latter may have overestimated the true burial age of the Galería deposits. The luminescence ages obtained indicate that the top of the basal sterile sands (GIb) at Galería have an age of up to ?370 thousand years (ka), while the lowermost sub-unit containing Mode II Acheulean lithics (base of unit GIIa) was deposited during MIS 9 (mean age?=?313±14 ka; n?=?4). The overlying units GIIb-GIV, which contain the richest archaeopalaeontological remains, were deposited during late MIS 8 or early MIS 7 (?240 ka). Galería Complex may be correlative with other Middle Pleistocene sites from Atapuerca, such as Gran Dolina level TD10 and unit TE19 from Sima del Elefante, but the lowermost archaeological horizons are ?100 ka younger than the hominin-bearing clay breccias at the Sima de los Huesos site. Our results suggest that both pIR-IR and single-grain TT-OSL dating are suitable for resolving Middle Pleistocene chronologies for the Sierra de Atapuerca karstic infill sequences. PMID:25338076

Demuro, Martina; Arnold, Lee J; Parés, Josep M; Pérez-González, Alfredo; Ortega, Ana I; Arsuaga, Juan L; Bermúdez de Castro, José M; Carbonell, Eudald

2014-01-01

57

New Luminescence Ages for the Galería Complex Archaeological Site: Resolving Chronological Uncertainties on the Acheulean Record of the Sierra de Atapuerca, Northern Spain  

PubMed Central

The archaeological karstic infill site of Galería Complex, located within the Atapuerca system (Spain), has produced a large faunal and archaeological record (Homo sp. aff. heidelbergensis fossils and Mode II lithic artefacts) belonging to the Middle Pleistocene. Extended-range luminescence dating techniques, namely post-infrared infrared stimulated luminescence (pIR-IR) dating of K-feldspars and thermally transferred optically stimulated luminescence (TT-OSL) dating of individual quartz grains, were applied to fossil-bearing sediments at Galería. The luminescence dating results are in good agreement with published chronologies derived using alternative radiometric dating methods (i.e., ESR and U-series dating of bracketing speleothems and combined ESR/U-series dating of herbivore teeth), as well as biochronology and palaeoenvironmental reconstructions inferred from proxy records (e.g., pollen data). For the majority of samples dated, however, the new luminescence ages are significantly (?50%) younger than previously published polymineral thermoluminescence (TL) chronologies, suggesting that the latter may have overestimated the true burial age of the Galería deposits. The luminescence ages obtained indicate that the top of the basal sterile sands (GIb) at Galería have an age of up to ?370 thousand years (ka), while the lowermost sub-unit containing Mode II Acheulean lithics (base of unit GIIa) was deposited during MIS 9 (mean age?=?313±14 ka; n?=?4). The overlying units GIIb-GIV, which contain the richest archaeopalaeontological remains, were deposited during late MIS 8 or early MIS 7 (?240 ka). Galería Complex may be correlative with other Middle Pleistocene sites from Atapuerca, such as Gran Dolina level TD10 and unit TE19 from Sima del Elefante, but the lowermost archaeological horizons are ?100 ka younger than the hominin-bearing clay breccias at the Sima de los Huesos site. Our results suggest that both pIR-IR and single-grain TT-OSL dating are suitable for resolving Middle Pleistocene chronologies for the Sierra de Atapuerca karstic infill sequences. PMID:25338076

Demuro, Martina; Arnold, Lee J.; Parés, Josep M.; Pérez-González, Alfredo; Ortega, Ana I.; Arsuaga, Juan L.; Bermúdez de Castro, José M.; Carbonell, Eudald

2014-01-01

58

Comparison of the genetic background of different Colombian populations using the SNPforID 52plex identification panel.  

PubMed

Various strategies for analysing SNP markers and genotyping have been published with the goal of obtaining informative profiles from biological samples that contain only small amounts of template and/or degraded DNA. In this study, a multiplex assay of 52 autosomal single-nucleotide polymorphisms (SNPs) was used to analyse 438 individuals from urban populations from different regions of Colombia, as well as a sample of 50 Native American individuals of the Pastos ethnic group from Nariño. To determine if significant differences in these 52 SNPs exist between the distinct regions of Colombia, genetic distance and admixture analyses were performed based on the available data for 17 different Colombian population groups and for population groups from Africa, Europe and America. The results demonstrate significant differences between the populations from the Southwest Andean, Central-West Andean, Central-East Andean, Orinoquian and northern Colombian Pacific Coast regions. Most of the regions exhibited a European and Native American admixture. One exception is the population from the region of Chocó (on the northern Pacific Coast), which exhibits a high proportion of African admixture (54 %). From the observed genetic backgrounds, it is possible to conclude that a single reference database for the entire country would not be suitable for forensic purposes. The allele frequencies and the forensically relevant parameters were calculated for all of the markers in each Colombian region with significant values for the combined matching probability (power of discrimination ?0.99999999999999990) and the combined probability of exclusion (?0.9990) in trios that were obtained from all of the population groups. PMID:23665814

Ibarra, Adriana; Freire-Aradas, Ana; Martínez, Martha; Fondevila, Manuel; Burgos, German; Camacho, Mauricio; Ostos, Henry; Suarez, Zuleyma; Carracedo, Angel; Santos, Sidney; Gusmão, Leonor

2014-01-01

59

The Asteroid 2000 ET70  

NASA Astrophysics Data System (ADS)

The asteroid 2000 ET70 (162421) was discovered by Lincoln Laboratory ETS (LINEAR) in New Mexico on March 8, 2000. Whiteley (2001) classified 2000 ET70 as an X-type object: This asteroid belongs to an ambiguous group that includes objects that are large and dark, metallic.The composition of this asteroid is unknown.The asteroid was at 0.0454430 U.A from the Earth on February 19.85956 (2012) and it will be at approximately 0.1503270 A.U from the Earth on August 21.07061 (2012).The asteroid 2000 ET70 was studied by radar in Arecibo and Goldstone. Shantanu Naidu and Jean-Luc Margot studied this object by Arecibo radar (Feb 13-2012) and they suggest that 2000 ET70 is roughly 1.5 km in diameter and that it has a period of rotation of about 9.5 hours. It has an orbital period of 0.92 years.From our Observatory, located in Pasto-Colombia, we captured several pictures, videos and astrometry data during three days. Our data was published by the Minor Planet Center (MPC) and also appears at the web page of NEODyS. Our observatory’s code at the MPC is “H78”. Pictures of the asteroid were captured with the following equipment: 14” LX200 GPS MEADE (f/10 Schmidt-Cassegrain Telescope) and STL-1001 SBIG camera.Astrometry was carried out, and we calculated the orbital elements. We obtained the following orbital parameters: eccentricity = 0.1243231, semi-major axis = 0.94541495 A.U, orbital inclination = 22.32919 deg, longitude of the ascending node = 331.05007 deg, argument of perihelion = 45.20913 deg, orbital period = 0.92 years (335.76 days), mean motion = 1.07218658 deg/d, perihelion distance = 0.82787796 A.U, aphelion distance = 1.06295195 A.U. The parameters were calculated based on 71 observations (2012 Mar. 1-7) with mean residual = 0.262 arcseconds.

Vodniza, Alberto Q.; Pereira, M. R.

2012-10-01

60

Application of Vegetation Indices to Estimate Acorn Production at Iberian Peninsula  

NASA Astrophysics Data System (ADS)

The Iberian pig valued natural resources of the pasture when fattened in mountain. The variability of acorn production is not contained in any line of Spanish agricultural insurance. However, the production of arable pasture is covered by line insurance number 133 for loss of pasture compensation. This scenario is only contemplated for breeding cows and brave bulls, sheep, goats and horses, although pigs are not included. This insurance is established by monitoring ten-day composites Normalized Difference Vegetation Index (NDVI) measured by satellite over treeless pastures, using MODIS TERRA satellite. The aim of this work is to check if we can use a satellite vegetation index to estimate the production of acorns. In order to do so, two Spanish grassland locations have been analyzed: regions of Olivenza (Jerez-Oliva) and Merida (Badajoz). The acorns production was evaluated through 2002-2005 gauging conducted by the Grupo Habitat de la Orden (Badajoz). Medium resolution (500x500 m2) MODIS images were used during the same time period to estimate the ten-day composites NDVI at these locations. Finally, meteorological data was obtained from SIAR and MAGRAMA network stations, calculating the ten-day averaged temperature and ten day accumulated precipitation. Considering two accumulated factors, NDVI and temperature, three phenological stages were well defined being the second one which pointed differences among campaigns. Then, accumulated precipitation versus accumulated NDVI was plot for this second phenological stage obtaining maximum differences at 300 mm of cumulative rainfall. Analyzing acorn production with accumulated NDVI in that moment a production function was obtained with a correlation coefficient of 0.71. These results will be discussed in detail. References J.A. Escribano, C.G.H. Diaz-Ambrona, L. Recuero, M. Huesca, V. Cicuendez, A. Palacios-Orueta y A.M. Tarquis. Aplicacion de Indices de Vegetacion para evaluar la falta de produccion de pastos y montaneras en dehesas. I Congreso Iberico de la Dehesa y el Montado. 6-7 Noviembre, 2013, Badajoz. J.A. Escribano Rodriguez, A.M. Tarquis, C.G. Hernandez Diaz-Ambrona. Pasture Drought Insurance Based on NDVI and SAVI. Geophysical Research Abstracts, 14, EGU2012-13945, 2012. EGU General Assembly 2012. Juan Escribano Rodriguez, Carmelo Alonso, Ana Maria Tarquis, Rosa Maria Benito, Carlos Hernandez Diaz-Ambrona. Comparison of NDVI ?elds obtained from different remote sensors. Geophysical Research Abstracts, 15, EGU2013-14153, 2013. EGU General Assembly 2013 Acknowledgements. This work was partially supported by ENESA under project P10 0220C-823.

Escribano, Juan A.; Díaz-Ambrona, Carlos G. H.; Recuero, Laura; Huesca, Margarita; Cicuendez, Victor; Palacios, Alicia; Tarquis, Ana M.

2014-05-01

61

The Asteroid 1998 QE2  

NASA Astrophysics Data System (ADS)

This big asteroid was at 5.8 millions of kilometers from the Earth on May 31 (2013) and it has a diameter of 2.7 km. The radar images obtained by JPL showed that the period of rotation around its axis is close to five hours. Hills. K (2013) reported that the period is of 5.281 +/- 0.002 hours. On June 4 the team of Goldstone-Arecibo found a period of 4.75 +/- 0.01 hours. We also contributed with the light and phase curves to estimate the period by means of the telescope (with red filter). The radar imagery (JPL and Arecibo) revealed that 1998 QE2 has a moon, and we captured a mutual event (eclipse). From our Observatory, located in Pasto-Colombia, we captured several pictures, videos and astrometry data during several days. Our data was published by the Minor Planet Center (MPC) and also appears at the web page of NEODyS. The pictures of the asteroid were captured with the following equipment: CGE PRO 1400 CELESTRON (f/11 Schmidt-Cassegrain Telescope) and STL-1001 SBIG camera. We obtained the light curve of the body. Astrometry was carried out, and we calculated the orbital elements. We obtained the following orbital parameters: eccentricity = 0.5692181, semi-major axis = 2.41104631 A.U, orbital inclination = 12.82771 deg, longitude of the ascending node = 250.16876 deg, argument of perihelion = 345.61328 deg, mean motion = 0.26326658 deg/d, perihelion distance = 1.03863508 A.U, aphelion distance = 3.78345755 A.U. The asteroid has an orbital period of 3.74 years The parameters were calculated based on 191 observations (2013 May: 17-24) with mean residual = 0.162 arcseconds. A video of the asteroid from our Observatory was published on the main page of the “SPACEWEATHER” web: http://www.spaceweather.com/archive.php?view=1&day=21&month=05&year=2013 Note: The autors would like to thank to: Dr. Alessondra Springmann (Arecibo Observatory), Dr. Petr Pravec (Czech Republic), Dr. Lance Benner (JPL), Dr. Carl Hergenrother (Target Asteroids Team), and Dr. Dolores Hill (Target Asteroids Team) for their special suggestions.

Vodniza, Alberto Q.; Pereira, M. R.; Arecibo Observatory Team; JPL Target Asteroids Team

2013-10-01

62

N-P-K balance in a milk production system on a C. nlemfuensis grassland and a biomass bank of P. purpureum CT-115 clone  

NASA Astrophysics Data System (ADS)

In very intensive milk production systems in Europe and America with the use of high amounts of chemical fertilizers, the nutrient recycling models consider the losses by leaching and N volatilization, as well as the hydro physical characteristics of the soil affecting the performance of this element (10; 6). However, in more extensive milk production systems, low input agriculture forming the natural cycle occurring within each farm, is of vital importance to potentate nutrient recycling for a stable animal production. The objective is the determination of the values of N, P and K inputs and outputs in a dairy farm with a sward composed by 60% of C. nlemfuensis and 40% of P. purpureum CT-115, associated with legumes in 28% of the area and the balance of these nutrients in the system using the "Recycling" software proposed by Crespo et al (2007). The grassland covered an area of 53.4 ha, composed by C. nlemfuensis (60%), P. purpureum CT-115 (40%) and L. leucocephala and C. cajan legumes intercropped in 28% of the area. The dairy herd consisted of 114 cows, 35 replacement heifers and 24 calves. There was a milk yield of 100 000 litters and the animals consumed 825 t DM from pastures and 75.1 t DM from other supplementary feeds. Nutrients extracted by pastures, nutrients intake by animals from pastures, symbiotically N fixation by legumes and N, P and K determinations outside the system due to animal production were determined (3-11). Volatilized ammonia, nutrient input and litter accumulated in the paddocks were measured once each season of the year. In the whole system the balance indicates negative values of N, P and K. Out of the total amount of nutrients consumed, animals used only 16 kg N, 5 Kg P and 4 Kg K for milk production, LW gain and calf production, the remainder returned to the system through excretions. Hence, more than 90% of the N and K, and approximately 81% of the P consumed by the animals were recycled to the system through the excretions. These results agree with those reported by Jarvis (1993) and Cadish et al (1994). However, 40% of the excretions occurred in the shade buildings and milking parlours ant thus these nutrients did not recycle in the system. An important internal recycling mechanism, especially for nitrogen and potassium, is their remobilization by the rejected pasture to re-use them for the regrowth activity. This is of particular interest in CT-115 Bank, since stems of CT-115 plants left after grazing remobilize an important amount of these nutrients, guarantee a favourable pasture regrowth (Martinez 1996). The return of all the excretion to the grassland is recommended as well as increasing the area of legumes to attain a satisfactory balance of N, P and K in the system. Further studies must consider maintenance fertilization, nutrient losses due to leaching and denitrification, as well as variation of the stable OM in the soil and the influence of hydro physical properties in the recycling process. The "Recycling" software was effective to determine the balance of nutrients in the dairy farm. Cadish, G., Schunke, R.N & Giller, K.E. 1994. Nitrogen cycling in a pure grass pasture and a grass-legume mixture on a red latosol in Brazil. Tropical Grasslands 28:43. Crespo G. y Rodríguez, I. 2006. Contribución al conocimiento del reciclaje de los nutrientes en el sistema suelo-pasto-animal. Instituto de Ciencia Animal, Editorial EDICA, La Habana, Cuba, 94 pp. Hirata, M., Sugimoto, Y.G & Ueno, M.1991. Use of a mathematical model to evaluate the effects of dung from grazing animals on pasture production. J. Japan Grassld. Sci. 37:303.

Crespo, G.; Rodriguez, I.; Martinez, O.

2009-04-01

63

Knowledge Sharing and Collaboration in Volcanic Risk Mitigation at Galeras Volcano, Colombia: A Participative Workshop to Reduce Volcanic Risk  

NASA Astrophysics Data System (ADS)

Galeras has been in nearly constant activity during modern historic times (roughly the past 500 years). Approximately 10,000 people live within an area designated as the highest-hazard and nearly 400,000 people are within areas of potential harmful effects. A wide variety of stakeholders are affected by the hazards, including: farmers, indigenous villagers, and people in urban environments. Hazards assessment and volcano monitoring are the responsibility of the Colombian Geological Survey (INGEOMINAS), whereas decisions regarding mitigation and response procedures are the responsibility of various governmental offices and the national emergency system (SNPAD). According to the current plan, when the risk level rises to a high level the people in the highest risk zone are required to evacuate. The volcano currently is in a very active, but fluctuating, condition and a future large eruption in a medium time frame (years to decades) is possible. There is a growing level of discomfort among many of the affected groups, including indigenous communities, farmers, and urban dwellers, related to the risk assessment. The general opinion prior to July 2009 was quite polarized as the decision makers saw the people of the region as poorly prepared to understand this hazard, whereas the population felt that their views were not being heard. The result was that the people in the hazardous areas decided not to evacuate, even during the current period of explosive activity. To resolve this situation the University of Nariño (Colombia) and the State University of New York at Buffalo organized a workshop named "Knowledge, Sharing and Collaboration in Volcanic Risk Mitigation at Galeras Volcano, Colombia" that was held in Pasto (Colombia), between 6 and 11 July, 2009. The general objective of this workshop was to analyze the existing hazard maps and safety plans for Galeras and form a bridge connecting scientists, decision makers, and other stake holders to promote a better understanding of the hazards presented by Galeras and the measures needed for mutual understanding and protection of people and property in the potentially threatened areas. Progress towards developing trust was achieved by requiring all the parties, including technicians, scientists, administrators and even farmers and indigenous people to listen to each others’ perceptions thought the entire week of the workshop. On the final day of the meeting a roundtable dialogue between the conflicting parts was moderated by social scientists. This intercourse identified, in a consensual manner, points of agreement to serve as starting positions for finding solutions to the areas of conflict. Irresolvable points were also identified during this roundtable discussion. The workshop showed that by sharing information within the framework of a full and frank communication, accepting (or at least listening to) each others’ arguments and trying to understand different points of view and served as a framework for an ongoing process of dialogue focused on resolving conflicts between the various stakeholder groups, even though they had previously reached the point of radicalized positions and statements.

Sheridan, M. F.; Cordoba, G. A.

2009-12-01

64

Ground-water in the Teresina-Campo Maior area, Piaui, Brazil  

USGS Publications Warehouse

The Teresina-Campo Maior area lies in a presently developing farming and grazing region near the margin of drought-prone northeast Brazil where irrigated farming offers the best potential for economic development. The area comprises 9,700 square kilometers largely of catinga-covered tabular uplands which are drained by the perennial Rio Parnatba. The climate is hot and humid most of the year but with distinct wet and dry seasons. Temperature extremes range from 20?C to 39?C and the annum rainfall averages 1,200 millimeters. The area's ground-water reservoir is contained chiefly in sandstone aquifers of six westward-dipping sedimentary rock formations, all part of the Maranhao sedimentary basin. The youngest of these formations, namely the Piaut (Pennsylvarian), Poti (Mississippian), Longa (Upper Devonian), and Cabecas (Middle Devoniar), contain the principal aquifers. Precipitation is the primary source of recharge to these aquifers and is more than sufficient to replenish current withdrawals from wells. Underlying the principal aquifers are the untapped Pimenteiras and Serra Grande Formations (both Lower Devonian) which in areas adjacent to the report area are moderately good to excellent water producers. These aquifers are recharged principally by lateral inflow from the east. Water also occurs in the alluvial deposits (Quaternary) underlying the flood plain of the Rio Parnatba but recurrent and uncontrolled flooding at present (1966) precludes their development. Of little economic importance, because they lie above the zone of saturation, are the thin erosional remnants of the Pastos Bons (Upper Triassic), Matuca, and Pedra de Fogo (both Permian) Formations. There are in the report area about 200 drilled wells most of which are pumped with power-driven engines. The wells range from 40 to 500 meters deep but most do not exceed 150 meters, and practically all are completed open hole. Yields range from 500 liters per day for 6-inch-diameter domestic wells to 240,000 liters per hour for 10-inch high-capacity municipal wells. Although there are many more dug wells than drilled wells, dug wells account for less than 1 percent of the current (1966) draft. The current annual withdrawal from the principal aquifers is approximately 5 million cubic meters of which almost half is used for municipal supply and the rest for rural household and irrigation uses. Additional water for public supply is available from aquifers now being pumped, and larger yields probably could be obtained from rural wells designed to take full advantage of the aquifer. Analyses of 28 samples show that the chemical quality of the water is well below the accepted limits of mineral concentration for most uses. Water from the Longa Formation averages 842 milligrams per liter in total dissolved solids and is more mineralized than that in the Piaul and Port Formations which contain water averaging less than 300 milligrams per liter. The water in the Piaui and Poti aquifers is the most suitable in the area for irrigation and has SAR values of C1-S1 and C2-S1. The quantities of water currently being used for irrigation are relatively small (600,000 cubic meters annually) but will increase substantially when intensive irrigation becomes a reality. Divisio de Hydrogeologia da Superintendancia do Desenvolvimento do Nordeste estimates that about 2,500 million cubic meters of water per year would be needed to irrigate about 250,000 hectares in the Teresina-Campo Maior area (about 25 percent of the total area). This goal, however, is not likely to be realized as the water requirement is five times the estimated natural recharge to the aquifers of the area. Most of the water-bearing formations in the report area have barely been tapped and can be developed a great deal more. In fact, the current annual withdrawal from the principal aquifers is less than 0.0025 percent of a conservative estimate of annual replenishment from rainfall. Additionally, only the

Rodis, Harry G.; Suszczynski, Edison F.

1972-01-01