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| CORREA-ARANEDA,FRANCISCO; URRUTIA,JONATHAN; FIGUEROA,RICARDO. |
| Los humedales boscosos de agua dulce son áreas naturalmente inundadas o saturadas, que sustentan vegetación boscosa hidrófila, están presentes en todo el mundo, y en Chile son conocidos como "pitrantos, hualves o hualhues". El presente estudio entrega el estado del conocimiento de estos humedales en Chile, mediante una descripción de sus características biológicas, fisicoquímicas e hidrodinámicas, identificando las principales amenazas para su conservación y las principales necesidades de investigación. Estos ambientes pueden presentar inundación permanente o temporal, dependiendo de un conjunto de procesos microclimáticos, biológicos y edafológicos. Su vegetación, del tipo hidrófila boscosa, es dominada por especies de la familia Myrtaceae. Tanto el... |
| Tipo: Journal article |
Palavras-chave: Agua dulce; Chile; Cuencas; Humedal boscoso; Vegetación hidrófila. |
| Ano: 2011 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2011000300002 |
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| BUSTAMANTE,ANA V; MATÉ,MARÍA L; LAMAS,HUGO E; GIOVAMBATTISTA,GUILLERMO; ZAMBELLI,ANDRÉS; VIDAL-RIOJA,LIDIA. |
| Este trabajo describe la variabilidad genética actual de tres poblaciones de llamas (Lama glama) del noroeste argentino (NOA), afectadas a la producción de fibra. Originariamente, las tropas fueron una única población la cual fue subdividida hace 10 años. Se estudiaron muestras de ADN de 77 animales mediante amplificación por PCR de 12 loci microsatélite con cebadores específicos de llama. La alta variabilidad genética comprobada se sustenta en el hallazgo total de 140 alelos diferentes, 9 a 16 alelos por locus y rangos de heterocigosidad observada y esperada por locus de 1 a 0 y 0,9 a 0,47, respectivamente. Diecinueve de treinta y seis pruebas de equilibrio de Hardy-Weinberg mostraron desvíos significativos (P < 0,05) debidos a una deficiencia de... |
| Tipo: Journal article |
Palavras-chave: Camélidos sudamericanos; Diversidad genética; Estructura poblacional; Marcadores microsatélite; Manejo. |
| Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2006000200004 |
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| ACEBES,PABLO; TRABA,JUAN; PECO,BEGOÑA; REUS,MARÍA L; GIANNONI,STELLA M; MALO,JUAN E. |
| Defining plant communities in desert zones is difficult due to large scale homogeneity and small scale heterogeneity, thus making provision of systematic information for conservation decisions problematic. We analysed plant communities of the most arid sector of Monte Desert for structure, plant composition and environmental variables. Small-scale variables such as slope, rock cover, bare ground and litter, as well as large-scale ones such as species diversity, composition and similarity within and between sites were included. Analyses of floristic composition showed the difficulty of segregating distinct communities due to high internal heterogeneity and overlap between the different sites. Only mesquite woodlands, a community situated at the extreme of... |
| Tipo: Journal article |
Palavras-chave: Arid environment; Heterogeneity; Shrubland; Similarity; Species richness. |
| Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2010000300007 |
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| ARTIGAS,JORGE N.; LEWIS,PETER D.; PARRA,LUIS E.. |
| This paper examines the status and geographic distribution of the genera Hypenetes Loew and Tillobroma Hull; the status of the latter was shifted to generic level by Artigas & Papavero 1991. The genus Clavator Philippi, which is preoccupied, becomes synonymous to Tillobroma Hull, this has been proposed by Artigas & Papavero (1991), and is confirmed here. Hypenetes and Tillobroma have a possible common Gondwanan origin of approximately 180 millions years ago. Even though the external characters barely allow separation between the two genera, the obvious differences in spermathecae structures permit the inference of other internal differences and reinforce the independent status of the genera. This conclusion is also supported by 180 million... |
| Tipo: Journal article |
Palavras-chave: Taxonomy; Asilidae; Tillobroma; Hypenetes; New species; Morphology. |
| Ano: 2005 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2005000300012 |
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| MORENO,RODRIGO A; NEILL,PAULA E; ROZBACZYLO,NICOLÁS. |
| Boring polychaetes infesting the shells of aquacultured molluscs affect host fitness and cause serious economic problems for the aquaculture industry. In Chile, knowledge of the native and non-indigenous polychaete fauna associated with mollusc hosts is limited, in spite of the fact that numerous native and non-indigenous mollusc species are actively harvested. We present the first complete list of boring polychaete species present in Chile, with a review of the information regarding each species' status as a native or non-indigenous species (NIS), together with information on native and introduced ranges, affected host species, likely vectors of introduction and donor areas. We recorded a total of nine boring polychaetes present along the Chilean coast... |
| Tipo: Journal article |
Palavras-chave: Bioinvasions; Legislation; Management; NIS; Southeastern Pacific. |
| Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2006000200012 |
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| McWHORTER,TODD J.; LOPEZ-CALLEJA,M. VICTORIA. |
| Balance between energy acquisition and expense is critical for the survival and reproductive success of organisms. Energy budgets may be limited by environmental factors as well as by animal design. These restrictions may be especially important for small endotherms such as hummingbirds, which have exceedingly high energy demands. Many nectar-feeding bird species decrease food intake when sugar concentration in food is increased. This feeding response can be explained by two alternative hypotheses: compensatory feeding and physiological constraint. The compensatory feeding hypothesis predicts that if birds vary intake to maintain a constant energy intake to match energy expenditures, then they should increase intake when expenditures are increased.... |
| Tipo: Journal article |
Palavras-chave: Energetics; Digestion; Feeding behavior; Hummingbirds; Nectarivory. |
| Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2000000300008 |
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| BASTIDAS-NAVARRO,MARCELA; MODENUTTI,BEATRIZ. |
| La presencia de macrófitas en la zona litoral lacustre trae aparejada condiciones diferentes con respecto a la zona pelágica, en particular en la disponibilidad de recursos. Por esta razón, las zonas litorales pueden presentar una mayor biodiversidad. En este trabajo se analizó la distribución horizontal de tecamebas y rotíferos en el lago Escondido (Argentina), vinculándola con los recursos alimentarios presentes en las diferentes zonas. Se tomaron muestras para el estudio del fitoplancton y zooplancton durante verano y primavera (2001-2003) en cuatro estaciones litorales y una pelágica. Se realizó el recuento de rotíferos y tecamebas y se determinó la abundancia y la biomasa fitoplanctónica. Los recursos alimentarios fueron clasificados en nanoplancton... |
| Tipo: Journal article |
Palavras-chave: Zona litoral; Zona pelágica; Tecamebas; Rotíferos; Recursos algales. |
| Ano: 2007 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2007000300008 |
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| GUERRERO,CARLA; ESPINOZA,LUIS; NIEMEYER,HERMANN M; SIMONETTI,JAVIER A. |
| The distribution and habitat use by carnivores can be assessed by studying their tracks or feces. If these methods are to be used confidently, they should not only unequivocally discriminate among species, but should also render the same patterns of spatial distributions. We assessed the fulfillment of these requirements with five carnivores inhabiting the Maulino forest of central Chile: Galictis cuja, Oncifelis guigna, Pseudalopex culpaeus, Pseudalopex griseus, and Puma concolor. Fecal bile acid thin layer chromatographic profiles were assessed, and shown to be species-specific, invariant within samples of a given individual and among individuals of a given species, but consistently different across species. The spatial distribution of feces in mixed... |
| Tipo: Journal article |
Palavras-chave: Fecal bile acids; Galictis; Habitat use; Oncifelis; Pseudalopex; Puma; Thin layer chromatography. |
| Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2006000100008 |
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| SPOTORNO,ÁNGEL E; VALLADARES,JOHN P; MARÍN,JUAN C; ZEBALLOS,HORACIO. |
| To investigate the origin and diversity of domestic guinea-pigs Cavia porcellus (Linnaeus, 1758; Rodentia, Caviidae), we sequenced the mitochondrial cytochrome b gene of 12 domestic and 10 wild specimens from six species, including the two presumed as ancestral to the domestic one: Cavia tschudii and Cavia aperea. All maximum parsimony and maximum likelihood analyses grouped C. porcellus with C. tschudii (mean K2P distance = 3.2 %); best trees had 609 steps (CI = 0.796; Bremer support Index (SI) = 28), and a _Ln = 4419.52, with 100 % and 97 % bootstrap support respectively. This clade, supported by three substitutions and 96 % bootstrap, is also obtained in the cladistic analysis of corresponding amino acids. When the C.... |
| Tipo: Journal article |
Palavras-chave: Andes; Cavidae; Cytochrome b; Domestication; Guinea pig; Molecular phylogeny. |
| Ano: 2004 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2004000200004 |
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| MUÑOZ,GABRIELA; VALDEBENITO,VERÓNICA; GEORGE-NASCIMENTO,MARIO. |
| Conocer qué, cuánto, cuándo y dónde comen y viven los hospedadores permitiría complementar los estudios parasitarios, ya que la transmisión de los endoparásitos está estrechamente ligada a la dieta, y la de los ectoparásitos al uso del hábitat. Por esto, se describen y comparan la composición y características cuantitativas de la dieta y de las infracomunidades de parásitos metazoos del torito Bovichthys chilensis con datos obtenidos de 108 ejemplares juveniles recolectados desde la zona intermareal de cuatro localidades de la costa de Chile (entre 33º y 40º S), y de 14 adultos recolectados desde el submareal somero de una quinta localidad (36º S), y se discute los resultados a la luz de los cambios ontogenéticos en el nicho de este huésped. Cerca del 70 %... |
| Tipo: Journal article |
Palavras-chave: Dieta; Parásitos; Ontogenia; Bovichthys chilensis; Chile. |
| Ano: 2002 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2002000400003 |
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| MATURANA-ROMESIN,HUMBERTO; MPODOZIS,JORGE. |
| In this article we propose that the mechanism that gave rise to the diversity of living systems that we find today, as well as to the biosphere as coherent system of interrelated autonomous living systems, is natural drift. And we also propose that that which we biologists connote with the expression natural selection is a consequence of the history of the constitution of the biosphere through natural drift, and not the mechanism that generates that history. Moreover, we do this by proposing: a) that the history of living systems on earth is the history of the arising, conservation, and diversification of lineages through reproduction, and not of populations; b) that biological reproduction is a systemic process of conservation of a particular... |
| Tipo: Journal article |
Palavras-chave: Evolution; Natural drift; Natural selection; Lineage; Organism; Species. |
| Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2000000200005 |
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| DEMERGASSO,CECILIA; CHONG,GUILLERMO; GALLEGUILLOS,PEDRO; ESCUDERO,LORENA; MARTíNEZ-ALONSO,MAIRA; ESTEVE,ISABEL. |
| Se estudiaron las comunidades estratificadas de microorganismos fotosintéticos que se encuentran en el Salar de Llamará ubicado en el desierto de Atacama, norte de Chile, mediante métodos microscópicos y espectrofotométricos. El espesor de la zona fótica de los tapetes descritos varió entre 8 y 30 mm lo cual podría atribuirse a la granulometría y la composición mineralógica de los sedimentos. Se diferencian tres tipos de tapetes. El primero con una única capa pigmentada de color verde; el segundo con capas de colores verde y naranja y un tercero en el que se observa, además de las capas verde y naranja, una de color púrpura. En uno de los sitios muestreados no se encontraron capas pigmentadas. Debajo de la zona pigmentada el sedimento es de color blanco,... |
| Tipo: Journal article |
Palavras-chave: Chile; Tapetes microbianos; Salares; Desierto; Bacterias fototróficas. |
| Ano: 2003 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2003000300012 |
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| RAPOPORT,EDUARDO H.. |
| The percentage of exotic plant species (PES) at large geographic scales is presented in form of political maps (Texas and North America) and of isoline maps (Great Britain). In the latter case it is possible to visualize that higher proportions of alien invaders are present in urban and industrial areas as well as in maritime ports rather than in agricultural lands. Consequently, it is possible to predict that the ratio of urban to agricultural species will continue to increase in the future. Based on a survey of 200 world floras, a multiple regression analysis is presented in order to determine the importance of different factors in the yield of PES values. The contribution to the total variance was: disturbance degree 55 %; total species richness 14%;... |
| Tipo: Journal article |
Palavras-chave: Invasions; Dispersal rates; Cosmopolitanism; Great Britain; North America; Texas. |
| Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2000000200012 |
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| GINOCCHIO,ROSANNA; BAKER,ALAN J.M.. |
| In Latin America, metallic ores are abundant and diverse. However, few metal-tolerant and metal hyperaccumulator plants have been reported in the region in comparison with other areas of the world. This may be largely explained by the scarcity of scientific studies of the native vegetation growing on natural mineralized or metal-contaminated areas and the unfrequent use of biogeochemical prospecting techniques by the local mining industry, rather than the proven absence of these plants. Latin America is, however, an area where metal-tolerant and hyperaccumulator plants (metallophytes) should be found, not only because of the wealth of ore deposits and associated metal polluted areas, but also due to its high and unique plant diversity. If plant formations... |
| Tipo: Journal article |
Palavras-chave: Hyperaccumulators; Metal-tolerant plants; Biodiversity; Metal ores; Biogeochemistry. |
| Ano: 2004 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2004000100014 |
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| Registros recuperados: 845 | |
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