|
|
|
|
|
| Gantz,Alberto; Valdivia,Carlos E; Yañez,Miguel; Sade,Soraya. |
| Numerous vertebrates, and in particular birds, ingest stones (geo-gastrolites) to favour the breakdown and digestion of food in the muscular stomachs. Between 1993 and 1994 we evaluated the quantity, relative abundance and quality of autochthonous (geo-gastrolites) and allochthonous (pieces of glass) components of the grit in gizzards of black-faced ibis (Theristicus melanopis) inhabiting the pastures of southern Chile. Grit elements were present in 32 out of 48 (66,7%) of all gizzard analysed. A total of 572 particles were recorded from which, 69.1% corresponded to autochthonous elements and 27.8% were allochthonous particles. Both components are similar in shape; however glass contributes considerably more in terms of mass. Gender differences reveal that... |
| Tipo: Journal article |
Palavras-chave: Black-faced ibis; Glasses; Gastrolites; Pastures; South Chile. |
| Ano: 2013 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-65382013000100003 |
| |
|
|
| Valdivia,Carlos E; Romero,Cristian R. |
| En la zona central de Chile se encuentra el bosque espinoso de Acacia caven y Prosopis chilensis, donde persiste menos del 40% de su superficie original, aunque sin representación en las áreas silvestres protegidas. Debido a la acción del ganado, se ha sugerido una contracción poblacional de P. chilensis acoplado a una expansión poblacional de A. caven lo cual, sin embargo, no ha sido verificado empíricamente. En cuatro sitios correspondientes a dos microcuencas de la Región Metropolitana en Chile (Batuco y Huechún), se evaluó la incidencia de las perturbaciones ambientales (ganado, conejos, malezas, basuras), el estado fitosanitario y estructura poblacional de P. chilensis, así como las dinámicas de regeneración de este árbol y A. caven, mediante el uso... |
| Tipo: Journal article |
Palavras-chave: Algarrobos; Espinos; Degradación ambiental; Extirpaciones futuras. |
| Ano: 2013 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432013000100007 |
| |
|
|
| Orellana,José I; Smith-Ramírez,Cecilia; Rau,Jaime R; Sade,Soraya; Gantz,Alberto; Valdivia,Carlos E. |
| BACKGROUND: Frugivorous birds are phenologically linked to the fruits that they eat. When there is less fruit in seasonal environments, frugivorous birds complement their diet by eating invertebrates. The depth of the phenological link between frugivorous birds and their dietary resources has not been studied until now. The objective was to determine the possible phenological synchrony between the Austral thrush (Turdus falcklandii) and its dietary resource, fruits and annelids, found in the fragmented forests in the South of Chile. RESULTS: The numbers of thrushes, annelids, and fruits in fragments of native forest and anthropogenic grassland in Chile's Lake District were estimated annually. Spatial variation (i.e., forest and grassland) and seasonal... |
| Tipo: Journal article |
Palavras-chave: Annelids; Fleshy fruit; Phenology; Seasonality; Turdus. |
| Ano: 2014 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2014000100010 |
| |
|
|
| Valdivia,Carlos E; Cisternas,Mauricio A; Verdugo,Gabriela S. |
| The extent to which plants depend on pollinators for outcross pollen transportation is a key issue in plant reproductive ecology. We evaluated the putative breeding system, foral display, and natural pollination in two Southern Cone of South American orchids, Gavilea araucana and G. venosa, by performing four hand pollination trials (agamospermy, autogamy, geitonogamy, and xenogamy tests) and by counting each fower and fruit produced by plants in natural conditions. Fruit set differed signifcantly depending on the origin of pollen as well as on the presence of a pollen vector. None of these species produced fruits by the agamospermy tests, therefore indicating that they require the presence of pollen on the stigmas for fruit setting. By contrast, only G.... |
| Tipo: Journal article |
Palavras-chave: Autogamy; Allogamy; Self-compatibility; Foral display; Fruiting patterns. |
| Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432010000100005 |
| |
|
|
|
