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| Registros recuperados: 160 | |
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| Abreu,Marcia Matos de; Pereira,Luiz Henrique Garcia; Vila,Vilma Barretto; Foresti,Fausto; Oliveira,Claudio. |
| Catfishes of the genus Pseudoplatystoma are very important species due to both their high commercial value and their ecological role as voracious predators. They undertake lengthy migratory movements during their life-cycle, this including reproductive migration which occurs from October to December in the rainy season. In the present study, seven microsatellite loci were analyzed to access genetic variability in two samples of P. reticulatum from the Upper Paraguay Basin. The loci were highly polymorphic (mean = 7.28). According to all analysis, the two samples of P. reticulatum revealed pronounced genetic differentiation. Fst value was 0.2290, Rst value 0.1067 and AMOVA 22.90% (Fst) and 10.67% (Rst), all being highly significant (p < 0.001). The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish; Population genetics; Microsatellite; Homing; Population structure. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000400032 |
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| Aemero, Mulugeta; Boissier, Jerome; Climent, Deborah; Mone, Helene; Mouahid, Gabriel; Berhe, Nega; Erko, Berhanu. |
| Background: Human intestinal schistosomiasis caused by Schistosoma mansoni and urinary schistosomiasis caused by Schistosoma haematobium are endemic in Ethiopia. Although schistosomes look morphologically uniform, there is variation in infectivity, egg productivity and virulence due to variation in their genetic make. Knowing the genetic diversity and population structure of S. mansoni isolates will enable to understand and consider the possible variability in terms of infectivity, egg productivity and virulence. Methods: Between 2010 and 2011, genetic diversity and population structure of Schistosoma mansoni isolates from four endemic areas of Ethiopia was assessed using previously published 11 polymorphic microsatellite loci. Miracidia were hatched from... |
| Tipo: Text |
Palavras-chave: Schistosoma mansoni; Microsatellite; Genetic diversity; Population structure; Ethiopia. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00302/41369/71868.pdf |
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| Antacli, J.C.. |
| This Thesis contributes to elucidate the life cycle strategies of two copepod species, the medium-size clausocalanid Drepanopus forcipatus Giesbrecht, 1888 and the large calanid Calanus australis Brodsky, 1959, in relation to the environmental conditions in the southern Patagonian shelf (47°-55°S). This research was mainly carried out with samples collected in late summer/early autumn (March/April, 2004) onboard RV "Dr. E. L. Holmberg" (INIDEP, Mar del Plata). An additional sampling performed during early spring (October, 2005) with RV "Puerto Deseado" (CONICET) was also utilized. The present study was based on the following research questions: 1) Which is the available food for copepod populations by late summer? 2) Which is the relative contribution of... |
| Tipo: Theses and Dissertations |
Palavras-chave: Zooplankton; Trophic levels; Population structure; Hydrography; Community composition. |
| Ano: 2011 |
URL: http://hdl.handle.net/1834/4205 |
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| Apín, Y. C.; Ocaña, F. A.; Cala de la Hera, Y. R.; Gómez, L. M.. |
| El género Emerita es muy común en playas de arena, donde juega un importante papel en las tramas tróficas. En este trabajo se caracteriza la estructura poblacional de Emerita sp. en playa Levisa, Granma, Cuba. Se analizan variables como la densidad poblacional, biomasa, talla de los individuos, así como abundancia de hembras fresadas y la talla mínima de las hembras ovígeras, en cuatro estaciones de muestreo. El valor más elevado de la densidad total fue de 188.3 ind. m-2 en el mes de octubre, mientras que en julio se obtuvo la mayor densidad de hembras ovígeras con un valor de 40 ind. m-2. Los valores de biomasa total (húmeda) oscilaron entre 14.5 g m-2 y 37.7 g m-2. Se clasificaron los individuos por tallas en 18 intervalos de clase, presentando... |
| Tipo: Preprint |
Palavras-chave: Population structure; Population structure; Http://aims.fao.org/aos/agrovoc/c_6115. |
| Ano: 2010 |
URL: http://hdl.handle.net/1834/3634 |
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| Aranha,José Marcelo Rocha; Caramaschi,Érica Pellegrini. |
| The population structure, reproductive aspects and feeding of Phalloceros caudimaculatus (Hensel, 1868), Poecilia vivipara Bloch & Schneider (1801), Phalloptychus januarius (Hensel, 1868) e Jenynsia lineata (Jenyns, 1842) were studied in five sampling stations in the Ubatiba stream, municipality of Maricá (State of Rio de Janeiro, Brazil). In relation to the population structure, P. caudimaculatus was more representative upstream; P. vivipara mid-stream and downstream; P. januarius and J. lineata downstream. The species presented preponderance of females, except in the intermediate length classes. The occurence of imatures and females with young pointed out a long reproductive period and favoured areas for reproduction of the four species. The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cyprinodontiformes; Population structure; Feeding; Reproduction; Coastal stream. |
| Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751999000300005 |
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| Arruda,Mauricio P.; Costa,William P.; Recco-Pimentel,Shirlei M.. |
| Abstract The Morato's Digger Toad, Proceratophrys moratoi, is a critically endangered toad species with a marked population decline in southern Brazilian Cerrado. Despite this, new populations are being discovered, primarily in the northern part of the distribution range, which raises a number of questions with regard to the conservation status of the species. The present study analyzed the genetic diversity of the species based on microsatellite markers. Our findings permitted the identification of two distinct management units. We found profound genetic structuring between the southern populations, on the left margin of the Tietê River, and all other populations. A marked reduction was observed in the contemporary gene flow among the central populations... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Proceratophrys moratoi; Microsatellite; Population structure; Management unit; Conservation. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572017000300502 |
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| Barboza,Deise Mari; Marques,Márcia Cristina Mendes; Pedrosa-Macedo,José Henrique; Olckers,Terence. |
| Solanum mauritianum Scopoli (Solanaceae), a native Brazilian shrub, has become naturalized and invasive in several countries. In South Africa, where invasions are severe, herbivorous insects that attack S. mauritianum in its native area have been considered for introduction as biological control agents. To assess the action of such herbivores on the plant, studies were carried out on a population of S. mauritianum in an area undergoing regeneration in southern Brazil. An analysis of the structure of that population was performed, as well as of herbivory by insects, in particular of Anthonomus (Curculionidae). The population structure showed an "inverted J" pattern in diameter classes, but not in height classes. Individual plants showed an aggregate... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Population structure; Solanum; Anthonomus; Herbivory; Biological control. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132009000200019 |
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| Barretto, A.C.. |
| The age-class distribution of the Brazilian flathead Percophis brasiliensis in relation to environmental variables in spring and winter, and the growth of both sexes, were studied in the SW Atlantic Coastal System (SACS)(34°S-31° S). Growth was studied from 1449 individuals (n=853, spring (1998 + 2000), n=596, winter (2004)) to which size (TL), sex, and age were determined. Age was determined considering that an opaque plus a hyaline band (present in the transverse section of the sagitta otolith) represented 1 year of life. The age-class distribution in spring and winter was established through hierarchical clustering and non-metric multi-dimensional scaling (nMDS analysis). This analysis grouped sampling stations (n=109, spring 1998; n=160, winter 2004)... |
| Tipo: Theses and Dissertations |
Palavras-chave: Age groups; Age composition; Environmental factors; Geographical distribution; Population structure; Growth; Environmental effects; Coastal waters; Age composition; Environmental factors; Geographical distribution; Population structure; Growth; Age groups; Coastal waters; Http://aims.fao.org/aos/agrovoc/c_29093; Http://aims.fao.org/aos/agrovoc/c_2594; Http://aims.fao.org/aos/agrovoc/c_5083; Http://aims.fao.org/aos/agrovoc/c_6115; Http://aims.fao.org/aos/agrovoc/c_3394; Http://aims.fao.org/aos/agrovoc/c_28628; Http://aims.fao.org/aos/agrovoc/c_25205. |
| Ano: 2007 |
URL: http://hdl.handle.net/1834/3017 |
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| Beltrán Rodríguez, Leonardo Alejandro. |
| Hintonia latiflora “quina amarilla” habita en el Bosque Tropical Caducifolio, es medicinal por lo que se comercializa la corteza interna. La recolecta es excesiva y las poblaciones están cada vez más distantes y escasas. No se cuenta con información biológica, ecológica y social que permita establecer criterios para la gestión y conservación de la especie, por ello, el presente estudio se desarrolló en Tlalcozotitlán, Guerrero, el sitio de cosecha comercial de quina. Se documentó la historia natural y antropógena de H. latiflora sustentada en la literatura científica y en observaciones de campo; se investigó la estructura poblacional, la influencia de la cosecha de corteza sobre caracteres arquitectónicos, reproductivos y en la densidad, además, se... |
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Palavras-chave: Quina amarilla; Historia natural; Factores físicos; Estructura poblacional; Corteza medicinal; Gestión comunitaria; Yellow quina; Natural history; Physical factors; Population structure; Medicinal bark; Community management; Botánica; Maestría. |
| Ano: 2013 |
URL: http://hdl.handle.net/10521/2183 |
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| Bertignac, Michel; Fernandez, Carmen; Methot, Richard. |
| European hake (Merluccius merluccius) is widely distributed over the north-east Atlantic shelf, from Norway to Mauritania. Despite its large distribution (covering ICES Division IIIa, Subareas IV, VI and VII and Divisions VIIIa,b,d, from Norway to the Bay of Biscay) and a complex population structure, the so-called northern stock of hake is currently assessed as a single unit, using a spatially aggregated implementation of the Stock Synthesis assessment model. In this study, a preliminary spatially explicit implementation of Stock Synthesis is developed, which accounts for the distribution of the hake population during its life cycle (nurseries and spawning areas) and the distribution of the fleets (trawlers, gillnetters and long-liners) exploiting the... |
| Tipo: Text |
Palavras-chave: Northern hake; Spatial dynamics; Population structure; Spatial stock assessment.. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00126/23764/21657.pdf |
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| Bosa,Cláudia Regina; Masunari,Setuko. |
| A study of the population of the xanthid crab Pilumnus dasypodus Kingsley, 1879 from rocky shore at the Farol Isle (25º51'S and 48º32'W) was carried out in the following aspects: temporal and spatial distributions of density, annual fluctuation of the sex ratio, size composition of the population and reproductive activities of the species. Monthly, four leveis in relation to emmersion time within intertidal zone were sampled, from May/90 to April/91, but Pilumnus dasypodus was obtained only in the levels 2, 3 and 4. The surface water temperature ranged from 16.0ºC (July/90) to 28.0ºC (February/91). A total of 775 individuais of Pilumnus dasypodus were collected among which, 92 were ovigerous females. The population density ranged from 14.63 ind.m-3... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pilumnus dasypodus; Population structure; Farol Isle; Paraná State. |
| Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752000000400016 |
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| Registros recuperados: 160 | |
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