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Registros recuperados: 38 | |
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Dueñas López, Gmelina. |
Los jaguares (Panthera onca) debido a sus amplios ámbitos hogareños son susceptibles a los efectos de la fragmentación. Para disminuir tales efectos, los corredores biológicos han sido propuestos como una herramienta para conectar poblaciones aisladas. La Sierra Madre Oriental (SMO) es una unidad de conservación para los jaguares que se considera con baja probabilidad de sostener poblaciones. Se identificaron corredores biológicos potenciales para el jaguar dentro de la SMO, por medio de técnicas de reconocimiento espacial. Mediante el algoritmo Maxent se identificaron parches de hábitat potencial, y a partir del Proceso Jerárquico Analítico y la Combinación Lineal Ponderada se generó una matriz de resistencia. El modelo con los corredores potencialmente... |
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Palavras-chave: Dispersión; SIG; Rutas de menor costo; Stepping-stone; Dispersion; GIS; Least cost path; Ganadería; Maestría. |
Ano: 2013 |
URL: http://hdl.handle.net/10521/2030 |
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CAMPOS, Z. M. da S.; MOURÃO, G. de M.; COUTINHO, M. E.; MAGNUSSON, W.. |
O estudo dos padrões de movimento dos jacarés do Pantanal ocorreu em uma área de lagos isolados e em uma área cortada por rios intermitentes no Pantanal. Foram marcados jacarés em 100 lagos, na área de lagos (1986-2001), e em 2 rios, na área de rios (1987-1999), recapturados 163 machos adultos, 132 fêmeas adultas e 237 jovens e monitorados 67 jacarés adultos por radiotelemetria nas duas áreas. No intervalo de 2 anos, a maioria dos jovens moveram-se apenas dentro da área de lagos ou da de rios, numa distância máxima de 6,0 km (x = 0,5; DP = 1,0 km), na área de lagos, e de 1,25 km (x= 0,6; DP = 0,3 km), na área de rios. Somente cinco jovens marcados nos lagos foram recapturados depois de um intervalo de 5 a 10 anos. Um jovem permaneceu na área de lago e... |
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) |
Palavras-chave: Yacare; Movement ecology; Dispersion; Caimans; Management.; Dispersão; Ecologia; Manejo; Jacaré; Movimento.; Pantanal.. |
Ano: 2004 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/811107 |
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Bailly Du Bois, P.; Dumas, Franck; Solier, L.; Voiseux, C.. |
Appropriate field data are required to check the reliability of hydrodynamic models simulating the dispersion of soluble substances in the marine environment. This study deals with the collection of physical measurements and soluble tracer data intended specifically for this kind of validation. The intensity of currents as well as the complexity of topography and tides around the Cap de La Hague in the centre of the English Channel make it one of the most difficult areas to represent in terms of hydrodynamics and dispersion. Controlled releases of tritium-in the form of HTO-are carried out in this area by the AREVA-NC plant, providing an excellent soluble tracer. A total of 14,493 measurements were acquired to track dispersion in the hours and days... |
Tipo: Text |
Palavras-chave: Modelling; Data collection; Tritium; Dispersion; Tidal dynamics; English Channel. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00077/18775/16484.pdf |
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Dufresne, Christiane; Duffa, Céline; Rey, Vincent; Verney, Romaric. |
L’objectif de ce travail est mettre en place un modèle hydro-sédimentaire de dispersion des radionucléides, comme outil d’aide à la décision suite à une hypothétique contamination marine accidentelle. Appliqué à la Rade de Toulon, il utilise le modèle MARS-3D pour l’étude hydrodynamique et le module MIXSED pour la dynamique des différentes classes de sédiments. Les cas d’application présentés concernent le césium et le plutonium, qui ont des affinités très différentes avec les sédiments fins. Les simulations de rejet, effectuées en fond de baie, montrent une variabilité saisonnière marquée, due aux conditions météorologiques typiques, mais aussi aux conditions de débit et de charge sédimentaire associée du fleuve Las, qui se jette dans la Rade. Ainsi, les... |
Tipo: Text |
Palavras-chave: Modélisation hydro-sédimentaire; Dispersion; Radionucléides; Toulon. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00348/45926/45619.pdf |
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Doglioli, Andrea; Nencioli, Francesco; Petrenko, Anne; Rougier, Gilles; Fuda, Jean-luc; Grima, Nicolas. |
The Lagrangian Transport Experiment (LATEX) was developed to study the influence of coupled physical and biogeochemical dynamics at the meso- and submesoscales on the transfers of matter and heat between the coastal zone and the open ocean. One of the goals of the Latex10 field experiment, conducted during September 2010 in the Gulf of Lion (northwest Mediterranean), was to mark a dynamical mesoscale feature by releasing a passive tracer [sulfur hexafluoride (SF6)] together with an array of Lagrangian buoys. The goal was to release the tracer in an initial patch as homogeneous as possible in the horizontal, and to study its turbulent mixing and dispersion while minimizing the contribution due to advection. For that, it was necessary to continuously adjust... |
Tipo: Text |
Palavras-chave: Dispersion; Lagrangian circulation; Transport; Ship observations; Tracers; Experimental design; Software. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00155/26590/24719.pdf |
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Thouvenin, Benedicte. |
Dans le cadre du programme national "REJETS URBAINS EN MER", développé par l'IFREMER, en collaboration avec l'Agence de Bassin Rhône Méditerranée Corse, des études sur le comportement d'un effluent émis par un émissaire en profondeur ont été réalisées. Complétant des mesures courantométriques et hydrologiques de longue durée, en un point à la sortie de l'émissaire de TOULON EST, deux modèles mathématiques ont été appliqués pour reproduire et étudier le rejet pendant les deux étapes de dilution. · Le modèle JET, développé par la SOGREAH, a été testé et comparé avec des mesures in situ. Les variations des résultats en fonction des conditions du milieu rencontrées pendant un cycle annuel ont été étudiées. Un modèle de transport et mélange multicouches a été... |
Tipo: Text |
Palavras-chave: Rejet urbain; Modèle mathématique; Rade de Toulon; Dispersion; Contamination. |
Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/00132/24287/22285.pdf |
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Bailly Du Bois, Pascal; Dumas, Franck. |
TRANSMER hydrodynamic model simulates dispersion of dissolved substances in seawater at the scale of the English Channel and the south of the North Sea with a mesh size of one kilometre and a time step of 30 minutes. This model evaluates the medium- and long-term consequences of releases of soluble pollutants in the marine ecosystem under normal or accidental conditions, at a very low computation cost (it takes less than one hour to simulate one year). It has been qualitatively and quantitatively validated by 1400 measurements of 125Sb in seawater in the English Channel and the North Sea. Budgets of measured and simulated radionuclide quantities are balanced for theses seas. The correlation factor between individual measurements in seawater and calculation... |
Tipo: Text |
Palavras-chave: Pollutant; Ecosystem; Radionuclides; Dispersion; Dissolved substances; Hydrodynamic model. |
Ano: 2005 |
URL: https://archimer.ifremer.fr/doc/2005/publication-552.pdf |
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Duffa, Celine; Dufois, Francois; Coudray, Sylvain. |
As part of its development of post-accident management tools, the French Institute for Radiological Protection and Nuclear Safety is setting up a model to simulate radionuclide dispersion in the Toulon marine area (one of France's main military ports). The model is based on the MARS 3D code developed by IFREMER. It reproduces hydro-sedimentation phenomena in the Bay of Toulon with a horizontal spatial resolution of 100 m and 30 vertical sigma levels and also factors in radioactive decay and dissolved/particulate distribution of the radionuclides studied. With no tide, the major currents in this area are generated by the wind. The model effectively reproduces the resulting hydrodynamic phenomena, which were measured throughout the summer of 2009 in the... |
Tipo: Text |
Palavras-chave: Bay of Toulon; Radionuclides; Dispersion; MARS. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00053/16465/15998.pdf |
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Vyzikas, Thomas; Stagonas, Dimitris; Maisondieu, Christophe; Greaves, Deborah. |
NewWave-type focused wave groups are commonly used to simulate the design wave for a given sea state. These extreme wave events are challenging to reproduce numerically by the various Numerical Wave Tanks (NWTs), due to the high steepness of the wave group and the occurring wave-wave interactions. For such complex problems, the validation of NWTs against experimental results is vital for confirming the applicability of the models. Intercomparisons among different solvers are also important for selecting the most appropriate model in terms of balancing between accuracy and computational cost. The present study compares three open-source NWTs in OpenFOAM, SWASH and HOS-NWT, with experimental results for limiting breaking focused wave groups. The comparison... |
Tipo: Text |
Palavras-chave: Extreme waves; Focused waves; Dispersion; Harmonic analysis; CFD; OpenFOAM; SWASH; HOS. |
Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00665/77755/79880.pdf |
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Millet, B. |
The wind-driven flow in the closed bassin de Thau is reproduced with a two-dimensional numerical model of horizontal ciruclation using an Alternate Direction Implicit scheme. A stochastic analysis of frequencies on a yearly time scale of the velocity fields computed in the model and a spatial and stochastic treatment of the term (H2 y2), similar to an effective coefficient of horizontal dispersion by shear effect are presented. This approach will allow the delineation, in a stochastic manner, of the main structures of the circulation in the lagoon and the spatial heterogeneity of its ecohydrodynamic features. Two attempts of analogical research are presented, with sorne examples of the spatial structure in the phytoplankton biomass and the map of the... |
Tipo: Text |
Palavras-chave: Lagune; Modèle; Circulation; Dispersion; Sédiment; Lagoon; Model; Circulation; Dispersion; Sediment. |
Ano: 1989 |
URL: http://archimer.ifremer.fr/doc/00323/43399/43093.pdf |
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Registros recuperados: 38 | |
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