947 research outputs found
Géneros de foraminíferos bentónicos en zonas mesofóticas superior y media del Parque Nacional Natural Corales de Profundidad y su potencial como bioindicadores de hábitats y cambios ambientales
The mesophotic coral reefs are part of the conservation object of the Corales de Profundidad Natural National Park (PNNCPR). A fundamental step for managing a protected area is the characterization of its specific richness, and benthic foraminifera is one of the essential taxonomic groups in reef environments. To our knowledge there are not published research about this topic in the PNNCPR, so it was necessary to study the genera of benthic foraminifera of the upper and middle mesophotic zones and explore a possible relationship of its composition in relation to its geographic and bathymetric ranges, as well as environmental changes. The results allowed us to conclude that a subsample of 50 individuals with shells in good condition taken from ten samples of 50 g was enough to estimate the composition of genera present in the study zone. The found genera richness was 53, from which Amphistegina, Quinqueloculina, and Triloculina were the most frequent. There were not significant differences found between the composition of benthic foraminifera genera between the upper (34 - 60 m) and middle (61 - 90 m) depth margin. The assemblage of benthic foraminifera in the Bajo Calamarí sector differs significantly from that found in the Bajo Frijol locality. The analysis of the similarity of samples using classification and ordination allowed us the identification of three groups in relation with the sampling site, time of year, and year of collection. The group of heterotrophs foraminifera (Quinqueloculina, Triloculina, Cibicides, Discorbis, Rosalina, Poroeponides, Textularia) was the most frequent, followed by symbiont (Amphistegina) and opportunistic foraminifera (Elphidium). The results obtained allow us to suggest that mesophotic benthic foraminifera have the potential to be bioindicators for the PNNCPR monitoring program.L
Los arrecifes coralinos mesofóticos hacen parte del objeto de conservación del Parque Nacional Natural Corales de Profundidad (PNNCPR). Un paso fundamental para el manejo de un área protegida es la caracterización de su riqueza específica, y uno de los grupos taxonómicos importantes en ambientes arrecifales son los foraminíferos bentónicos. Debido a que no existen investigaciones de este tipo para el PNNCPR, se consideró estudiar los géneros de foraminíferos bentónicos de las zonas mesofótica superior y media, y explorar una posible relación de dicha composición con sus ámbitos geográficos y batimétricos, así como con cambios ambientales. Los resultados permitieron concluir que una submuestra de 50 individuos con conchillas en buen estado, tomadas de diez muestras de 10 g, fue suficiente para estimar la composición de géneros presentes en la zona. La riqueza de géneros encontrada fue de 53, siendo Amphistegina, Quinqueloculina y Triloculina los que presentaron mayor frecuencia de aparición. No se encontraron diferencias significativas entre el conjunto de géneros de foraminíferos bentónicos de los estratos de profundidad superior (34-60 m) y medio (61-90 m). El conjunto de foraminíferos bentónicos del sector Bajo Calamarí difiere significativamente del encontrado en la localidad de Bajo Frijol. El análisis conjunto de la similaridad de muestras mediante clasificación y ordenación permitió identificar tres grupos congruentes con el sitio de muestreo, la época del año y el año de recolecta. El grupo de foraminíferos heterótrofos (Quinqueloculina, Triloculina, Cibicides, Discorbis, Rosalina, Poroeponides y, Textularia) fue el más frecuente, seguido por el de los foraminíferos simbiontes (Amphistegina) y oportunistas (Elphidium). Los resultados obtenidos permiten sugerir que los foraminíferos bentónicos mesofóticos tienen potencial de ser bioindicadores para el programa de monitoreo del PNNCPR
Lista de miriápodos (Arthropoda: Myriapoda) de la región Caribe colombiana
S
Con base en la literatura disponible, y revisión de colecciones de organismos, se realizó una lista de chequeo de 58 miriápodos para la región Caribe colombiana; 12 quilópodos y 46 diplópodos; en total, 16 familias (cuatro de Chilopoda y 12 de Diplopoda) de 11 órdenes (tres de Chilopoda y seis de Diplopoda). Para cada especie se incluyó su ámbito geográfico por departamentos, ámbito altitudinal, colección de referencia y fuente bibliográfica. Se confirmó la presencia en colecciones colombianas de especímenes de diplópodos que son nuevos registros de su grupo taxonómico para la región, como Chondrodesmus cf. riparius (Chelodesmidae), dos especies de Fuhrmannodesmidae, tres de Paradoxosomatidae y una de Lophoproctidae. Así mismo, dos especies de Scolopendrellidae de la clase Symphyla. Esto demuestra la imperiosa necesidad de completar los inventarios básicos de diversidad de los principales grupos de organismos ante el alarmante deterioro ambiental al que está sometida la región Caribe colombiana.Based on the available literature and a review of collections of organisms, a checklist of 58 myriapods was made for the Colombian Caribbean region; 12 chilopods and 46 diplopods; in total, 16 families (four from Chilopoda and 12 from Diplopoda) of 11 orders (three from Chilopoda and six from Diplopoda). Each species's geographical range by department, altitud, reference collection, and bibliographic source were included. The presence in Colombian collections of diplopod specimens that are new records of their taxonomic group for the region, such as Chondrodesmus cf. riparius (Chelodesmidae), two species of Fuhrmannodesmidae, three of Paradoxosomatidae and one of Lophoproctidae. Likewise, two species of Scolopendrellidae of the class Symphyla. This demonstrates the urgent need to complete the essential diversity inventories of the main groups of organisms in the face of the alarming environmental deterioration to which the Colombian Caribbean region is subjected
Extension of geographical distribution of three common species of diurnal butterflies (Lepidoptera: Papilionoidea) from the Colombian Caribbean
En este documento se registran tres especies comunes de mariposas diurnas de la región Caribe colombiana (Aides dysoni, Calpodes ethlius y Anteos clorinde). Los especímenes fueron capturados con red entomológica en muestreos realizados en el municipio de Arjona (departamento de Bolívar) en el año de 2015 entre las 8:00 y 16:00 horas. Para cada una de ellas se proporcionan caracteres morfológicos útiles para su reconocimiento y se complementa su distribución en el Neotrópico.In this document we extend the geographical distribution for three common species of diurnal butterflies from the Colombian Caribbean region (Aides dysoni, Calpodes ethlius, and Anteos clorinde). The specimens were captured with an insect net in samplings conducted in the Arjona jurisdiction (Bolivar, Deparment) in 2015, between 8:00 and 16:00 hours. For each of them we provide important morphological characters for their recognition, and complement their distribution in the Neotropic
Seasonal diversity of spider assemblages (Araneae: Arachnida) in the “Guillermo Piñeres” Botanical Garden, Turbaco–Colombia
Climatic seasons have been shown to determine the temporal fluctuations in species communities of different ecosystems. Here, we assessed the diversity of spider assemblages in dry, transition and rainy seasons in the "Guillermo Pineres" Botanical Garden (GPBG), Turbaco, Colombia. We collected spider assemblages between June 2018 and April 2019 through standardized day and night sampling methods for tropical ecosystems: looking up, looking down, beating and leaf litter sieving. In total, we collected 1585 individuals, belonging to 28 families and 112 (morpho) species. We calculated the effective species richness (Hill numbers) to evaluate the changes in diversity across seasons and used clustering and ordination methods (Jaccard index-based nMDS) to identify differences in the composition of the assemblages. Also, we compared the abundance and species richness of predatory guilds of the three seasons. The transition season showed the highest diversity with 94 morphospecies, an effective number of species of 48.7 and a dominance of 32.4 effective species. The clustering and ordination methods grouped the sampling events into three groups, each corresponding to a climatic season. The most abundant guild was the orb web weavers, with the highest value in the rainy season, while "other hunters" were the most species rich. Our results indicate that the spider assemblages in GPBG present a seasonal variation in diversity, probably influenced by climatic conditions. Understanding how these seasonal changes occur is necessary to develop forest management strategies for monitoring and management projects on the conservation of species assemblages according to the Convention on Biological Diversity.Peer reviewe
Afinidades biogeográficas de los galateoideos (Decapoda: Anomura) del Caribe y Pacífico colombiano
RESUMEN
Objetivo. Determinar la distribución y afinidades biogeográficas de los galateoideos de aguas colombianas con base en la literatura y muestras recolectadas durante expediciones realizadas entre 1999 y 2002. Materiales y métodos. Se recolectaron ejemplares en 100 estaciones entre 20 y 550 m de profundidad en el Caribe y Pacífico colombiano. El material recolectado, junto con la información geográfica existente en literatura para las especies conocidas para Colombia se emplearon para realizar mapas de distribución, los cuales se compararon con el “Mapa de ecorregiones marinas del mundo”. Resultados. Se obtuvo la información geográfica para 3247 ejemplares recolectados de 18 especies de los géneros Agononida, Anomoeomunida, Munida, Munidoposis y Pleuroncodes, y se complementó con la obtenida a partir de la literatura para las 40 especies de la superfamilia con presencia conocida en aguas colombianas. Se generaron cinco grupos principales de distribución: especies restringidas al Caribe, al Caribe y Atlántico occidental, Anfiatlánticas, restringidas al Pacífico oriental y Anfiamericanas. Se encontró que el 53 % de las especies recolectadas en el Caribe se presentan también en la provincia Atlántico Norte Cálido-Templado, y para el Océano Pacífico la mayor afinidad se da con la provincia Pacífico Oriental Tropical. Conclusiones. Los galateoideos en aguas colombianas presentan ámbitos geográficos y batimétricos amplios, presentándose simpatría entre algunas especies. Las de aguas someras presentan mayores restricciones que aquellas de distribución en aguas profundas. Los mecanismos de distribución de las especies corresponden con el ciclo de vida de cada una y las corrientes predominantes en las provincias
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger
Observatory and is used to detect the radio emission of cosmic-ray air showers.
These observations are compared to the data of the surface detector stations of
the Observatory, which provide well-calibrated information on the cosmic-ray
energies and arrival directions. The response of the radio stations in the 30
to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of
the incoming electric field. For the latter, the energy deposit per area is
determined from the radio pulses at each observer position and is interpolated
using a two-dimensional function that takes into account signal asymmetries due
to interference between the geomagnetic and charge-excess emission components.
The spatial integral over the signal distribution gives a direct measurement of
the energy transferred from the primary cosmic ray into radio emission in the
AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air
shower arriving perpendicularly to the geomagnetic field. This radiation energy
-- corrected for geometrical effects -- is used as a cosmic-ray energy
estimator. Performing an absolute energy calibration against the
surface-detector information, we observe that this radio-energy estimator
scales quadratically with the cosmic-ray energy as expected for coherent
emission. We find an energy resolution of the radio reconstruction of 22% for
the data set and 17% for a high-quality subset containing only events with at
least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy
We measure the energy emitted by extensive air showers in the form of radio
emission in the frequency range from 30 to 80 MHz. Exploiting the accurate
energy scale of the Pierre Auger Observatory, we obtain a radiation energy of
15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV
arriving perpendicularly to a geomagnetic field of 0.24 G, scaling
quadratically with the cosmic-ray energy. A comparison with predictions from
state-of-the-art first-principle calculations shows agreement with our
measurement. The radiation energy provides direct access to the calorimetric
energy in the electromagnetic cascade of extensive air showers. Comparison with
our result thus allows the direct calibration of any cosmic-ray radio detector
against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI.
Supplemental material in the ancillary file
Probing invisible neutrino decay with KM3NeT-ORCA
In the era of precision measurements of the neutrino oscillation parameters,
upcoming neutrino experiments will also be sensitive to physics beyond the
Standard Model. KM3NeT/ORCA is a neutrino detector optimised for measuring
atmospheric neutrinos from a few GeV to around 100 GeV. In this paper, the
sensitivity of the KM3NeT/ORCA detector to neutrino decay has been explored. A
three-flavour neutrino oscillation scenario, where the third neutrino mass
state decays into an invisible state, e.g. a sterile neutrino, is
considered. We find that KM3NeT/ORCA would be sensitive to invisible neutrino
decays with ~ at confidence
level, assuming true normal ordering. Finally, the impact of neutrino decay on
the precision of KM3NeT/ORCA measurements for ,
and mass ordering have been studied. No significant effect of neutrino decay on
the sensitivity to these measurements has been found.Comment: 27 pages, 14 figures, bibliography updated, typos correcte
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