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| SIMEONE,ALEJANDRO; LARA-JORQUERA,GUILLERMO; BERNAL,MARIANO; GARTHE,STEFAN; SEPÚLVEDA,FELIPE; VILLABLANCA,ROBERTO; ELLENBERG,URSULA; CONTRERAS,MACARENA; MUÑOZ,JULIETA; PINCE,TAMARA. |
| Between 1999 and 2003 we collected information on the breeding distribution and abundance of 12 seabird species occurring on nine islands off the coasts of north and central Chile (27°-33°S). The Peruvian booby Sula variegata was the most abundant seabird with a breeding population of ca. 18,000 pairs concentrated in two islands, followed by the Humboldt penguin Spheniscus humboldti with ca. 9,000 pairs, the largest colony being at Chañaral Island with ca. 7,000 pairs. Kelp gulls Larus dominicanus bred at all the surveyed sites in colonies of variable size, ranging from 40 to 2,000 pairs. Peruvian diving-petrels Pelecanoides garnotii and Peruvian pelicans Pelecanus occidentalis bred at restricted sites, but generally in large colonies. Magellanic penguins... |
| Tipo: Journal article |
Palavras-chave: Aves marinas; Colonia reproductiva; Abundancia; Conservación; Corriente de Humboldt; Chile. |
| Ano: 2003 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2003000200016 |
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| Cortés,Arturo; Rosenmann,Mario; Bozinovic,Francisco. |
| Studies on water balance in desert-dwelling granivorous rodents use evaporative water loss (EWL) and metabolic water production (MWP) to evaluate the efficiency of water regulation, expressed by the model Ta @ MWP = EWL, defined by an ambient temperature (Ta) value at (@) which MWP/EWL = 1. Here we evaluate and apply this model (1 - r²) determining water regulation efficiency, based on the energetic cost (MR) to maintain water balance (WB), that is MR-WB. To test the model, EWL was measured and MWP estimated in nine species of rodents from different localities of northern and north-central Chile (II and IV Regions): Octodon degus (Od) and O. lunatus (Olu) (Octodontidae), Abrothrix olivaceus (Ao), A. longipilis (Al), A. andinus (Ad), Phyllotis darwini (Pd),... |
| Tipo: Journal article |
Palavras-chave: Rodents; Water economy; Arid habitats; Chile. |
| Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2000000200006 |
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| TORRES-DÍAZ,CRISTIAN; CAVIERES,LOHENGRIN A; MUÑOZ-RAMÍREZ,CARLOS; K. ARROYO,MARY T. |
| La actividad de polinizadores puede ser afectada por factores bióticos (e.g., densidad floral en el parche, despliegue floral) o por factores abióticos (e.g., temperatura, velocidad de viento, nubosidad). A pesar de la notable variación local, estacional e interanual en temperatura en zonas alpinas, las consecuencias de la variación microclimática local sobre la actividad de los polinizadores han recibido escasa atención en ambientes de alta montaña. En este estudio comparamos las tasas de visita a flores de polinizadores realizadas sobre poblaciones de exposición norte y oeste, en Chaetanthera apiculata (3.100 m de altitud), y en poblaciones de exposición este y oeste en C. lycopodioides (3.300 m de altitud). Se estudiaron los sistemas de reproducción de... |
| Tipo: Journal article |
Palavras-chave: Microclima; Densidad floral; Tasa de visita floral; Chaetanthera; Alta montaña; Andes; Sistema reproductivo; Cambio climático. |
| Ano: 2007 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2007000400007 |
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| CAMPOS,CLAUDIA M; CAMPOS,VALERIA E; MONGEAUD,ARNALDO; BORGHI,CARLOS E; DE LOS RÍOS,CLAUDIA; GIANNONI,STELLA M. |
| The fate of Prosopis flexuosa seeds dispersed by cattle is dependant on the spatial pattern of dung deposition and foraging movements. We hypothesised that cattle-use site classes explain the response variables related to seed input and fate of seeds, seedlings and saplings (small plants more than one year old). We defined sites with heavy cattle traffic ("trails" and "periphery of trails"), sites used for resting and foraging ("under Prosopis"), and sites where isolated individuals only walk ("under shrubs" and "bare soil"). Considering the established cattle-use site classes, our specific goals were to quantify and compare: (1) seeds transported in cattle dung; (2) seedlings 10 months after dung deposition; (3) established saplings; and (4) germinated... |
| Tipo: Journal article |
Palavras-chave: Dung deposition; Endozoochory; Establishment; Germination; Seed input. |
| Ano: 2011 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2011000200013 |
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| KENAGY,G.J.; NESPOLO,ROBERTO F.; VÁSQUEZ,RODRIGO A.; BOZINOVIC,FRANCISCO. |
| We present an analysis of behavioral flexibility in a day-active caviomorph rodent, the degu, Octodon degus, in response to temporal (daily and seasonal), spatial, and thermal heterogeneity of its environment. We quantified activity and foraging behavior in a population, together with thermal conditions, in an open habitat in the seasonally hot and arid matorral of central Chile. Summer activity was bimodal, with a gap of more than 8 h between the morning bout of 2.5 h of intensive foraging and the afternoon bout of 2 h. More than half of the 4.5 h of summer activity occurred in the shade of early morning or late afternoon when the sun was below the local skyline. Autumn and spring activity were also bimodal, but with greater proportions of activity under... |
| Tipo: Journal article |
Palavras-chave: Foraging; Seasonality; Thermal ecology; Forrajeo. |
| Ano: 2002 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2002000300008 |
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| AGUILERA,MOISÉS A. |
| This paper reviews recent knowledge about the functional roles that herbivores have in intertidal communities in Chile. Specifically, I review field and laboratory studies dealing with the food preferences of herbivores, the responses of algae to herbivore attacks and reports of negative and positive functional effects of herbivores on algal populations and communities. Most herbivores studied are characterized as generalist species. Green ephemeral and a few corticated algae dominate diets, while all species considered ingest larvae and post-metamorphic stages of invertebrates challenging classical characterizations of the herbivore guild. Functional redundancy and complementarity within the herbivore guild is discussed in relation to both quantitative... |
| Tipo: Journal article |
Palavras-chave: Chile; Herbivores; Functional role; Guild; Intertidal. |
| Ano: 2011 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2011000200009 |
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| Suárez,Lorena H.; González,Wilfredo L.; Gianoli,Ernesto. |
| Convolvulus chilensis es una hierba perenne, única representante endémica de la familia Convolvulaceae en Chile. Se estudió el sistema de reproducción, fenología, morfología y longevidad floral de C. chilensis en una población natural ubicada en la localidad de Aucó, dentro de la Reserva Nacional Las Chinchillas, IV Región, Chile. Se montó un experimento de polinización controlada considerando los tratamientos de polinización natural, polinización cruzada, autopolinización manual, autopolinización automática y apomixis, evaluándose su efecto sobre la formación de frutos y el número de semillas producidas por fruto. Adicionalmente, se compararon los siguientes atributos de la progenie según tipo de polinización (autopolinización o polinización cruzada):... |
| Tipo: Journal article |
Palavras-chave: Convolvulaceae; Convolvulus chilensis; Sistema de reproducción; Autocompatibilidad; Autogamia. |
| Ano: 2004 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2004000400001 |
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| MUÑOZ-PEDREROS,ANDRÉS; MONCADA-HERRERA,JUAN; GÓMEZ-CEA,LAURA. |
| El paisaje es un patrimonio ambiental que incluye valores culturales y naturales, un recurso que representa la fisonomía de un espacio y refleja su naturaleza e historia. Por otro lado este recurso patrimonial se debe valorar y gestionar racionalmente, más aún cuando existe una demanda creciente por espacios de alto valor paisajístico para realizar actividades ecoturísticas. Respecto al estudio del paisaje visual, como elemento mesurable, no fue considerado hasta mediados del siglo XX y se ha avanzado en la valoración de la calidad, de la fragilidad y su capacidad de uso como valoración directa del paisaje. Sin embargo está pendiente el análisis indirecto que incluye sus características visuales básicas tales como línea, color, textura, configuración... |
| Tipo: Journal article |
Palavras-chave: Evaluación; Humedal; Paisaje visual; Sur de Chile. |
| Ano: 2012 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2012000100006 |
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| RIBEIRO,LEONARDO B.; SILVA,NAISANDRA B.; FREIRE,ELIZA M. X.. |
| This study assessed the reproductive and fat body cycles of Tropidurus hispidus (Spix, 1825) and T. semitaeniatus (Spix, 1825) in an area of caatinga in the Serido of Rio Grande do Norte, Brazil, from October 2006 to May 2008. In both species, the females were reproductively active from the middle of the dry season to the beginning of the rainy season. Female reproductive activity was influenced by precipitation, whereas males exhibited spermatozoa in their testes throughout the year, and their reproductive activity was not related to any of the climatic variables analyzed. Mean clutch size (± SD) was 8.1 ± 2.0 and 2.1 ± 0.6 eggs in T. hispidus and T. semitaeniatus, respectively, and was significantly related to female body size only in T. hispidus. The... |
| Tipo: Journal article |
Palavras-chave: Body size-fecundity; Clutch size; Minimum size at maturity; Reproduction; Semiarid. |
| Ano: 2012 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2012000300005 |
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| Chi,Shiyun; Li,Sixin; Chen,Sheng; Chen,Mingxiu; Zheng,Jinxiu; Hu,Juxiang. |
| Abstract Background The seasonal variations in macroinvertebrate communities in tropical, temperate and subarctic regions have been observed and well documented to date, but similar studies conducted in subtropical rivers at the regional scale are relatively rare. In this paper, the macroinvertebrate communities from the main tributaries in the Three Gorges Reservoir Catchment (TGRC) were investigated as a function of the four seasons to explore the temporal variations in macroinvertebrate communities and further tests the temporal stability of certain metrics that are based on macroinvertebrates under a routine bioassessment framework. Results The taxa richness reached the highest point in spring, followed by winter, autumn and summer. The taxa... |
| Tipo: Journal article |
Palavras-chave: Temporal variations; Macroinvertebrate communities; Three gorges reservoir catchment (TGRC); Tributaries. |
| Ano: 2017 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2017000100204 |
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| Rodríguez-Morelos,Víctor H; Soto-Estrada,Alejandra; Pérez-Moreno,Jesús; Franco-Ramírez,Alicia; Díaz-Rivera,Pablo. |
| BACKGROUND: Big-leaf mahogany (Swietenia macrophylla King) is the woody species with the highest economic value in Latin America. Currently, it is subject to intensive exploitation, diminishing its natural populations. Due to this decline, the species is a preferred species for reforestation and establishment of commercial tropical plantations. Mycorrhizal symbiosis is a biotic factor scarcely studied in the ecology of this species. Therefore, the objective of this research was to identify the diversity of arbuscular mycorrhizal fungi (AMF) species associated with the rhizosphere of seedlings and mature trees of big-leaf mahogany growing in its natural habitat, a tropical rain forest in Los Tuxtlas, Veracruz, Mexico. Soil samples from a 20-cm depth were... |
| Tipo: Journal article |
Palavras-chave: Arbuscular mycorrhizae; Morphospecies; Seedlings; Spores; Tropical trees. |
| Ano: 2014 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2014000100009 |
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| VELOSO,CLAUDIO; KENAGY,G.J.. |
| During lactation, both the nutritional and energetic requirements of suckling change gradually. These changes normally are accompanied by modifications in chemical composition of the milk. We investigated the temporal course of milk composition during lactation in a precocial caviomorph rodent, the "degu" (Octodon degus) under laboratory condition. Female degus were kept in laboratory during gestation and lactation and fed with commercial food pellets. Milk was collected at three stages of lactation: early (days 5-8, n = 12), middle (days 15-21, n = 7) and late (days 26-40, n = 6), and analyzed for protein, carbohydrates, lipids, ash, total solids and energy. On average, carbohydrates decreased from 3.1 ± 0.3 % (early) to 1.1 ± 0.3 % (late) during... |
| Tipo: Journal article |
Palavras-chave: Degu; Precocial; Lactation; Energy; Lipids; Milk composition. |
| Ano: 2005 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2005000200008 |
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| Registros recuperados: 845 | |
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