291 research outputs found
Gusanos blancos de la papa: biología y manejo.
Papa-Solanum tuberosu
Dynamic changes in the lower Gállego River (Ebro Basin, NE Spain) and their relationship with anthropic activities and the quaternary substrate
The lower Gállego River has been strongly degraded since the 1960s due to human activity (gravel mining, dump accumulation, channeling works), which has produced a deep channel incision. Although these humandriven processes are usually reported in fluvial bibliography, in this case, more complex results are observable. For instance, regarding the depth and incision rates, we observed no relationship between the most anthropically impacted areas and the sections with the deepest incisions; moreover, the deepening process continues 40 years after the human interventions ceased. The reason for this maladjustment is the role played by the exhumation of the underlying Pleistocene substrate, affected by the synsedimentary processes of karstification. The appearance of paleodolines filled with fine sediments on the incision bottom and sides is the main factor conditioning the continuity and magnitude of the process. Besides, these paleodepressions direct the river dynamics and course, thus favoring its widening when they appear and causing the development of a new riverbed (Qt13) while the 1960s floodplain (Qt12) is becoming an old terrace located between 5 and 11 m above the new alluvial bottom. There are no previous records about this kind of consequences in the regional fluvial dynamics.
El curso bajo del río Gállego ha sido fuertemente degradado desde los años 1960 por la actividad antrópica (extracción de áridos, acumulaciones de escombros, obras de encauzamiento) que ha conducido a una fuerte incisión. Aunque este tipo de procesos inducidos por el hombre son habituales en la bibliografía fluvial, en este caso se aprecian efectos más complejos. Son, por ejemplo, la profundidad y velocidad de la incisión, la falta de relación entre puntos de máxima intervención y los de mayor incisión o la continuidad del proceso cuarenta años después de cesar ese tipo de acciones. La respuesta a estos desajustes está en el papel que está jugando la exhumación del sustrato pleistoceno infrayacente, afectado por procesos sinsedimentarios de karstificación. La aparición de paleodolinas rellenas de sedimentos finos en el fondo y laterales de la incisión es actualmente el principal determinante de su importancia y continuidad. Además, estas paleodepresiones dirigen la dinámica y trazado del río y puntualmente favorecen ensanchamientos laterales. Esto propicia la aparición de un nuevo lecho (Qt13) a medida que el lecho de los años 1960 (Qt12) va quedando como una terraza colgada entre 5 y 11 m sobre el nuevo fondo aluvial. No hay antecedentes de este tipo de consecuencias en la dinámica fluvial regional
Environmental predictors of filarial infection in Amazonian primates : Ecological factors and primate filarial infection
Altres ajuts: acord transformatiu CRUE-CSICUTP en procés de revisióAltres ajuts: ERANet17/HLH-0271, and by the National Council for Scientific and Technological Development (CNPq) (grant number 201,475/2017-0).Filarial nematode infections are common in primates, but have received little attention in the Neotropics. Epidemiological data on filarial infections in primates are still too sparse to fully understand the complex of this parasitism, especially because of the difficulty in studying the ecology and epidemiology of wild primates. We describe natural infections by Dipetalonema parasitizing 211 primates belonging to eight free-living primate genera in Amazonia, and assess the relationships between parasitic indicators and climatic (rainfall and river level), ecological (fruiting periods of plants) and biological (sex, species' body mass, group size and density) factors. The overall prevalence was 64.4% (95% CI: 64.0 - 64.9); parasitic mean abundance (N filariae per individual) and parasitic mean intensity (N filariae per infected host) of infection were 11.9 (95% CI: 8.3 - 15.6) and 18.4 (95% CI: 13.4 - 23.4) filariae/individual, respectively. Although we observed differences in parasitic parameters among primate genera, there was no correlation between parasitic parameters with density, body mass or group size. Sapajus, Cebus and Lagothrix had the highest prevalence and parasitic mean intensity. Using Lagothrix lagotricha poeppigii, the most sampled species (n = 92), as a model, we found that the number of filariae per infected host was associated with fruit production in swamp forests during the dry season, the time of food scarcity. The long periods of food shortage may cause environmental stress on primates, impairing their immune defenses and leading to increased parasite load but not affecting infection prevalence. However, the lack of information on vector ecology, key to understand risk factors associated to infection rate, prevents confirming the existence of an infection pattern dependent on food availability
Cartografía histórica y reconstrucción paleotopográfica y geoarqueológica de la ciudad romana de caesar augusta (Zaragoza, España)
En este trabajo se ofrece una aproximación a la reconstrucción de la topografía y las características del terreno de Caesar Augusta (Zaragoza). Esta reconstrucción ha sido modelada integrando en un Sistema de Información Geográfico (SIG) el mapa topográfico de Casañal de 1880 –anterior a las principales transformaciones urbanas ocurridas en la ciudad- e información geomorfológica, geoarqueológica y arqueológica. Caesar Augusta fue fundada por los romanos junto al río Ebro en el siglo I aC sobre un asentamiento ibérico previo (Salduie). El área urbana ocupaba una terraza fluvial cuaternaria en la confluencia de los ríos Ebro y Huerva. Esta terraza se eleva unos 10 m sobre esos ríos, con altitudes que varían entre 200-208 m s.n.m. La topografía actual de la ciudad ha variado sustancialmente a lo largo del tiempo, de modo que no es apropiada para reconstruir la morfología original del terreno donde los romanos fundaron Caesar Augusta . Se ha utilizado ArcGIS 10.0 y sus módulos ArcMap y ArcScene para la gestión y análisis de los datos. Los modelos 3D generados muestran muchos elementos topográficos de detalle que en mapas anteriores pasaban desapercibidos. Estos modelos son complementados con datos de la naturaleza geológica del subsuelo provenientes de observaciones realizadas en diversas excavaciones arqueológicas. El modelo digital del terreno derivado del mapa de Casañal y las informaciones complementarias sólo son válidas para reconstrucciones generales. Sin embargo, ha mejorado nuestro conocimiento sobre muchos elementos romanos de Caesar Augusta (topografía del Decumanus y Cardo maximus , cloacas, fosos, muralla, teatro y foro). Y, es más, es ahora posible comprender mejor la geomorfología y el dinamismo fluvial de la ciudad de Zaragoza.
In this paper we provide a reconstruction of the topography and characteristics of the terrain of Caesar Augusta (the Roman name of the present-day city of Zaragoza). This reconstruction has been modelled using GIS and integrating the topographic map drawn by Casañal in 1880 –previous to the main urban transforma-tions-with geomorphological, geoarchaeological and archaeological data. Caesar Augusta was founded by Romans near the Ebro River in the 1st century BC in the same place where there was a previous Iberian settlement (Salduie). The urban area occupied a quaternary fluvial terrace in the confluence of the rivers Ebro and Huerva. The terrace stands about 10 m above these rivers, with a varying height between 208-200 masl. The present-day urban topography has suffered many transformations throughout history; therefore, it is impossible to reconstruct the original morphology of the land where the Romans decided to build their town in the past. We have used ArcGIS Desktop 10.0 and its platforms ArcMap and ArcScene for managing and analysing the data. 3D models show many fine topographic features that in were overlooked previous maps. These models are complemented with information about the underground geologic nature, which is known through the observations made in several archaeological excavations. The model derived from Casañal s map and complementary data is only valid for general reconstructions, but it has enhanced our knowledge of many elements of Caesar Augusta (topography of the Decumanus and Cardo maximus, sewage system, moats, wall, theatre, forum), making it possible to better understand the geomorphology and fluvial evolution of the city of Zaragoza
Holocene alluvial sequence in the val de zaragoza (Los Monegros) in the palaeoenvironmental context of the ebro basin (Ne Spain)
Flat-bottomed valleys formed by Holocene fills are the most characteristic landforms in the center of the Ebro basin. This paper analyzes, within a regional framework, a small fluvial basin located in the north of the Alcubierre Range. Three Holocene morphosedimentary units (H1-H3) and a sub-functional level (H4) are identified. These units are representative of the regional geomorphological evolutionary process in the Ebro basin. New chronological insights on climate and landscape management are provided by a study of the Bastarás weir, a construction made for water flow management during the Little Ice Age (LIA). The integration of Val de Zaragoza radiocarbon datings into the regional framework enables the authors to identify the main formation stages, as well as the influence of climatic and human factors on its evolution. The intensification of human pressure in the territory is reflected in a progressive increase in sediment accumulation rates in the valleys, peaking during Roman times and the Little Ice Age.
Los valles de fondo plano formados por rellenos holocenos constituyen los paisajes más característicos del sector central de la cuenca del Ebro. En este trabajo se analiza una pequeña cuenca fluvial localizada en el norte de la Sierra de Alcubierre, en la que se han identificado tres unidades morfosedimentarias holocenas (H1-H3) y un nivel subfuncional (H4), que son representativos de la evolución geomorfológica regional de la Cuenca del Ebro. Uno de los aspectos más relevantes del valle lo constituye el azud de Bastarás, construcción realizada durante la Pequeña Edad del Hielo para el aprovechamiento del agua, que aporta nuevos datos cronológicos sobre dicha época y acerca de la gestión del territorio. La integración de las dataciones radiocarbónicas obtenidas en la Val de Zaragoza en un marco regional ha permitido precisar las principales etapas de formación de los valles de fondo plano, así como la importancia de los factores climáticos y humanos en su evolución. La intensificación de la presión humana sobre el territorio queda reflejada en un progresivo aumento en las tasas de acumulación de sedimentos en los valles, alcanzando sus picos máximos en Época Romana y en la Pequeña Edad del Hielo
Identification and quantification of carbamate pesticides in dried lime tree flowers by means of excitation-emission molecular fluorescence and parallel factor analysis when quenching effect exists
A non-separative, fast and inexpensive spectrofluorimetric method based on the second order calibration of excitation-emission fluorescence matrices (EEMs) was proposed for the determination of carbaryl, carbendazim and 1-naphthol in dried lime tree flowers. The trilinearity property of three-way data was used to handle the intrinsic fluorescence of lime flowers and the difference in the fluorescence intensity of each analyte. It also made possible to identify unequivocally each analyte. Trilinearity of the data tensor guarantees the uniqueness of the solution obtained through parallel factor analysis (PARAFAC), so the factors of the decomposition match up with the analytes. In addition, an experimental procedure was proposed to identify, with three-way data, the quenching effect produced by the fluorophores of the lime flowers. This procedure also enabled the selection of the adequate dilution of the lime flowers extract to minimize the quenching effect so the three analytes can be quantified. Finally, the analytes were determined using the standard addition method for a calibration whose standards were chosen with a D-optimal design.
The three analytes were unequivocally identified by the correlation between the pure spectra and the PARAFAC excitation and emission spectral loadings. The trueness was established by the accuracy line “calculated concentration versus added concentration” in all cases. Better decision limit values (CCα), in x0 = 0 with the probability of false positive fixed at 0.05, were obtained for the calibration performed in pure solvent: 2.97 μg L−1 for 1-naphthol, 3.74 μg L−1 for carbaryl and 23.25 μg L−1 for carbendazim. The CCα values for the second calibration carried out in matrix were 1.61, 4.34 and 51.75 μg L−1 respectively; while the values obtained considering only the pure samples as calibration set were: 2.65, 8.61 and 28.7 μg L−1, respectively.theMinisteriodeEconomíayCompetitividad(CTQ2011-26022)
and JuntadeCastillayLeón(BU108A11-2
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