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| Registros recuperados: 57 | |
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| Winemiller,Kirk O.; Taphorn,Donald C.; Kelso-Winemiller,Leslie C.; López-Delgado,Edwin O.; Keppeler,Friedrich W.; Montaña,Carmen G.. |
| ABSTRACT We investigated spatial and seasonal variation of fish assemblages of Caño Maraca, a creek in Venezuela’s Western Llanos, a region with strong wet-dry seasonality. Fishes were surveyed over a 19-year period at three sites along the longitudinal gradient: a headwater site with a narrow channel, a middle site with shallow channels traversing a seasonal wetland, and a lower site where the channel has higher banks. Assemblage composition and presence of species with juveniles and various life history strategies were compared during wet and dry seasons. Overall, fish species richness was lowest at the headwater site and highest at the downstream site. During the wet season, however, species richness is greatest at the middle site, a pattern associated... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Dispersal; Fluvial gradient; Freshwater fish; Neotropics; Nestedness. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000400217 |
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| Cacho, Oscar J.; Hester, Susan M.. |
| Invasive species can cause significant damage to natural environments, agricultural systems, human populations and the economy as a whole. Biological invasions are complex dynamic systems which are inherently uncertain and their control involves allocation of surveillance and treatment resources in space and time. A complicating factor is that there are at least two types of surveillance: active and passive. Active surveillance, undertaken by pest control agencies, has high sensitivity but generally low coverage because of its high cost. Passive surveillance, undertaken by the public, has low sensitivity and may have high coverage depending on human population density. Its effectiveness depends on the extent to which information campaigns succeed in... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Search theory; Invasive species; Dispersal; Passive surveillance.; Environmental Economics and Policy. |
| Ano: 2011 |
URL: http://purl.umn.edu/100535 |
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| Cordazzo,César Vieira. |
| Cakile maritima occurs sporadically along the southern Brazilian coast, where it is restricted to more protected sites at the base of foredunes. Somatic dimorphism in C. maritima is manifested as morphologically distinct upper and lower fruit segments (silicules). The two morphs were tested for differences in size, number of seeds, dispersal ability and natural establishment. In the C. maritima population of southern Brazil, the lower silicule has more seeds than upper silicule, and lower seeds are more likely to abort than the upper ones. Seeds from upper segments were significantly larger than those from lower ones; however, their mass ranges overlap. The mean silicule mass was not significantly different from both segments, but the silicule/seed mass... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cakile; Dimorphic fruits; Dispersal; Seed production. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042006000200007 |
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| DOMÍNGUEZ,M. CECILIA; ROIG-JUÑENT,SERGIO A. |
| The purpose of this study was to achieve a hypothesis explaining the biogeographical history of the family Fanniidae, especially that of the species from Patagonia, the Neotropics, Australia, and New Zealand. We used "dispersal-vicariance analysis" (DIVA), an event-based parsimony method, to analyze the most parsimonious phylogenetic hypothesis for the family, obtained by Domínguez & Roig-Juñent (2008). The analysis resulted in 32800 alternative equally optimal reconstructions that indicate that the ancestor of the Fanniidae was widely distributed across different regions of the world, which along with the subsequent separation of two clades that correspond to the Laurasic and Gondwanan Landmasses allow the proposal of an older age than in previous... |
| Tipo: Journal article |
Palavras-chave: Age of Fanniidae; Dispersal; DIVA; Gondwana; Vicariance. |
| Ano: 2011 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2011000100005 |
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| Graells,Giorgia; Corcoran,Derek; Aravena,Juan Carlos. |
| BACKGROUND: Twenty beavers Castor canadensis (Castoridae) were initially introduced in the Argentinean portion of Tierra del Fuego Island, from where they have occupied most of the Fuegian Archipelago and even reached the continent. This invasion is causing great damage to the subantarctic forest ecosystems, and it is not known how fast the species is spreading. While there is an estimation of this advance using interviews, it is not known how reliable these are and they cannot be made in remote areas. On the mainland, where beavers were present, their date of arrival was estimated using interviews and dendrochronology, and the dates obtained by both methods were compared for each site. RESULTS: Differences were found among the groups of respondents,... |
| Tipo: Journal article |
Palavras-chave: Beaver; Dendrochronology; Dispersal; Cross dating; Surveys. |
| Ano: 2015 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2015000100003 |
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| Miranda,João M. D.; Bernardi,Itiberê P.; Moro-Rios,Rodrigo F.; Passos,Fernando C.. |
| This study was carried out in the Chácara Payquerê do Bugre, State of Paraná, Southern Brazil (25º29'52" S and 49º39'24" W) and reports on the demography of a group of Alouatta guariba clamitans Cabrera, 1940 followed monthly during three years (from February, 2002 to March, 2005). The growth and subsequent fission of the group are described and argued, as well as their possible underlying causes, focusing on the population ecology and social behavior of this taxa. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Brown howlers; Dispersal; Group fission; Group growth; Population ecology. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752006000300013 |
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| Araújo, Ricardo Alves de; Rodrigues, Rosane Cláudia; Costa, Clésio dos Santos; Santos, Francisco Naysson de Sousa; Cutrim Júnior, José Antonio Alves; Jesus, Ana Paula Ribeiro de; Shigaki, Francirose; Araújo, Jocélio dos Santos. |
| The objective was to evaluate the grazing behavior and the spatial distribution of feces of F1 young bulls from the cross between Nellore and Guzera on pastures of Urochloa brizantha cv. Marandu in silvopastoral systems composed of babassu palm (Attalea speciosa) and Marandu monoculture in the Pre-Amazon region of the state of Maranhão. Animals were evaluated in four systems consisting of 0, 80, 131, 160 palms ha-1, characterizing monoculture (mono), low density of palm trees (LD), medium density of palm trees (MD) and high density of palm trees (HD) during the rainy (RE) and dry (DE) periods. Five animals (repetitions) were used in each system, with 231-303 days of age and 180±15 kg body weight. Determinations of behavioral patterns were made by instant... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: 5.04.05.02-0 babassu; Sward structure; Dispersal; Idle; Palm trees; Rumination. |
| Ano: 2017 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/33085 |
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| Lamarca,Edmir V.; Prataviera,Juliana S.; Borges,Igor F.; Delgado,Liliana F.; Teixeira,Carmen C.; Camargo,Marcelo B.P. de; Faria,José M.R.; Barbedo,Claudio J.. |
| This study aims to analyze the maturation and dispersal of Eugenia pyriformis Cambess. seeds produced in different years, and the influence of variation in thermal and hydric environment on seed physical and physiological characteristics at dispersal. Fruits at different developmental stages were harvested in the city of São Paulo between 2003 and 2010, as well as in the cities of Campinas and Lavras, in 2009 and 2010 and analyzed for size and color. The seeds were extracted from the fruits and their dry mass, water content, germination and vigor were assessed. Results showed that seed maturation is unsynchronized to the maturation of the fruit, taking 45 days on average (430 growing degree-days), longer in rainy times or lower temperatures. Seeds with... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Dispersal; Development; Degree-day; Rainfall; Recalcitrants seeds. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652013000100223 |
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| Registros recuperados: 57 | |
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