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Search Results: 1 - 10 of 1767 matches for " Raimundo Real "
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Moluscos terrestres de las elevaciones cársticas de Vi?ales, Pinar del Río, Cuba
Oliva-Olivera,Wilfredo; Real,Raimundo;
Revista de Biología Tropical , 2009,
Abstract: land snails from the vi?ales limestone highlands, pinar del río, cuba. the land snails inhabiting the limestone highlands in cuba are poorly known. from field surveys, traditional collection catalogues, and the literature, we list 136 species, 49 genera and 19 families, 90 % of the species endemic to cuba; only five species are non-indigenous of the cuban archipelago. annulariidae and urocoptidae are the most represented families, and chondrothyra and liocallonia are the genera with the highest number of species. forty-four species of this list were absent from the consulted collections. we provide 16 new records of species in localities of the region; and 12 species seem to have become locally extinct. rev. biol. trop. 57 (3): 589-604. epub 2009 september 30.
Moluscos terrestres de las elevaciones cársticas de Vi ales, Pinar del Río, Cuba
Wilfredo Oliva-Olivera,Raimundo Real
Revista de Biología Tropical , 2009,
Abstract: De acuerdo a los muestreos efectuados en localidades representativas de las elevaciones cársticas de Vi ales (Cuba), la consulta de catálogos no automatizados de colecciones malacológicas y la revisión de la literatura, se dan a conocer 136 especies, agrupadas en 49 géneros y 19 familias, de moluscos terrestres procedentes de la región. El 90% de las especies identificadas son endémicas de Cuba y sólo cinco especies no son autóctonas del archipiélago cubano. Las familias mejor representadas son Annulariidae y Urocoptidae. Los géneros con mayor número de especies son Chondrothyra y Liocallonia. Cuarenta y cuatro especies detectadas en Vi ales no estaban representadas en las colecciones consultadas, y 23 de ellas han sido recolectadas en este trabajo y aportadas a las colecciones del Instituto de Ecología y Sistemática de Cuba. Se dan a conocer 16 nuevos registros de especies en localidades de la región, mientras que 12 especies parecen haberse extinguido localmente. Land snails from the Vi ales limestone highlands, Pinar del Río, Cuba. The land snails inhabiting the limestone highlands in Cuba are poorly known. From field surveys, traditional collection catalogues, and the literature, we list 136 species, 49 genera and 19 families, 90 % of the species endemic to Cuba; only five species are non-indigenous of the Cuban archipelago. Annulariidae and Urocoptidae are the most represented families, and Chondrothyra and Liocallonia are the genera with the highest number of species. Forty-four species of this list were absent from the consulted collections. We provide 16 new records of species in localities of the region; and 12 species seem to have become locally extinct. Rev. Biol. Trop. 57 (3): 589-604. Epub 2009 September 30.
Favourable areas for expansion and reintroduction of Iberian lynx accounting for distribution trends and genetic variation of the wild rabbit
A. Márcia Barbosa,Raimundo Real
Wildlife Biology in Practice , 2010,
Abstract: Although on a local scale Iberian lynx distribution is determined by the availability of prey rabbits, recent modelling analyses have uncovered broad-scale disagreements between these two species’ distribution trends. These analyses showed also that the lynx had become restricted to only a fraction of the rabbit’s genetic variability, and that this could be jeopardising its survival in the face of environmental hazards and uncertainty. In the present paper, a follow-up was carried out through the building of lynx and rabbit distribution models based on the most recent Spanish mammal atlas. The predictions of environmental favourability (which is an indicator of abundance) for lynx and rabbit were positively correlated within the lynx's current distribution area, but they were negatively correlated within the total Spanish area where lynx occurred in the 1980’s. Environmental favourability for rabbits was significantly higher where lynx maintains reproductive populations than where it recently disappeared, indicating that rabbit favourability plays an important role and can be a good predictor of lynx persistence. The lynx and rabbit models were extrapolated to predict favourable areas for both species in Spain as well as in Portugal, on the original scale of the distribution data (10x10 km) and on a 100 times finer spatial resolution (1x1 km). The lynx and rabbit models were also combined through fuzzy logic to forecast the potential for lynx occurrence incorporating information on favourable areas for its main prey. Several areas are proposed as favourable for lynx expansion or re-introduction, encompassing both countries and both genetic lineages of the rabbit.
Phylogeographic Triangulation: Using Predator-Prey-Parasite Interactions to Infer Population History from Partial Genetic Information
A. Márcia Barbosa, Guillermo Thode, Raimundo Real, Carlos Feliu, J. Mario Vargas
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0050877
Abstract: Phylogeographic studies, which infer population history and dispersal movements from intra-specific spatial genetic variation, require expensive and time-consuming analyses that are not always feasible, especially in the case of rare or endangered species. On the other hand, comparative phylogeography of species involved in close biotic interactions may show congruent patterns depending on the specificity of the relationship. Consequently, the phylogeography of a parasite that needs two hosts to complete its life cycle should reflect population history traits of both hosts. Population movements evidenced by the parasite’s phylogeography that are not reflected in the phylogeography of one of these hosts may thus be attributed to the other host. Using the wild rabbit (Oryctolagus cuniculus) and a parasitic tapeworm (Taenia pisiformis) as an example, we propose comparing the phylogeography of easily available organisms such as game species and their specific heteroxenous parasites to infer population movements of definitive host/predator species, independently of performing genetic analyses on the latter. This may be an interesting approach for indirectly studying the history of species whose phylogeography is difficult to analyse directly.
Past, Present and Future Distributions of an Iberian Endemic, Lepus granatensis: Ecological and Evolutionary Clues from Species Distribution Models
Pelayo Acevedo, José Melo-Ferreira, Raimundo Real, Paulo Célio Alves
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0051529
Abstract: The application of species distribution models (SDMs) in ecology and conservation biology is increasing and assuming an important role, mainly because they can be used to hindcast past and predict current and future species distributions. However, the accuracy of SDMs depends on the quality of the data and on appropriate theoretical frameworks. In this study, comprehensive data on the current distribution of the Iberian hare (Lepus granatensis) were used to i) determine the species’ ecogeographical constraints, ii) hindcast a climatic model for the last glacial maximum (LGM), relating it to inferences derived from molecular studies, and iii) calibrate a model to assess the species future distribution trends (up to 2080). Our results showed that the climatic factor (in its pure effect and when it is combined with the land-cover factor) is the most important descriptor of the current distribution of the Iberian hare. In addition, the model’s output was a reliable index of the local probability of species occurrence, which is a valuable tool to guide species management decisions and conservation planning. Climatic potential obtained for the LGM was combined with molecular data and the results suggest that several glacial refugia may have existed for the species within the major Iberian refugium. Finally, a high probability of occurrence of the Iberian hare in the current species range and a northward expansion were predicted for future. Given its current environmental envelope and evolutionary history, we discuss the macroecology of the Iberian hare and its sensitivity to climate change.
Updating Known Distribution Models for Forecasting Climate Change Impact on Endangered Species
Antonio-Román Mu?oz, Ana Luz Márquez, Raimundo Real
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0065462
Abstract: To plan endangered species conservation and to design adequate management programmes, it is necessary to predict their distributional response to climate change, especially under the current situation of rapid change. However, these predictions are customarily done by relating de novo the distribution of the species with climatic conditions with no regard of previously available knowledge about the factors affecting the species distribution. We propose to take advantage of known species distribution models, but proceeding to update them with the variables yielded by climatic models before projecting them to the future. To exemplify our proposal, the availability of suitable habitat across Spain for the endangered Bonelli's Eagle (Aquila fasciata) was modelled by updating a pre-existing model based on current climate and topography to a combination of different general circulation models and Special Report on Emissions Scenarios. Our results suggested that the main threat for this endangered species would not be climate change, since all forecasting models show that its distribution will be maintained and increased in mainland Spain for all the XXI century. We remark on the importance of linking conservation biology with distribution modelling by updating existing models, frequently available for endangered species, considering all the known factors conditioning the species' distribution, instead of building new models that are based on climate change variables only.
Combined Effects of the North Atlantic Oscillation and the Arctic Oscillation on Sea Surface Temperature in the Alborán Sea
José C. Báez, Luis Gimeno, Moncho Gómez-Gesteira, Francisco Ferri-Yá?ez, Raimundo Real
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0062201
Abstract: We explored the possible effects of the North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) on interannual sea surface temperature (SST) variations in the Alborán Sea, both separately and combined. The probability of observing mean annual SST values higher than average was related to NAO and AO values of the previous year. The effect of NAO on SST was negative, while that of AO was positive. The pure effects of NAO and AO on SST are obscuring each other, due to the positive correlation between them. When decomposing SST, NAO and AO in seasonal values, we found that variation in mean annual SST and mean winter SST was significantly related to the mean autumn NAO of the previous year, while mean summer SST was related to mean autumn AO of the previous year. The one year delay in the effect of the NAO and AO on the SST could be partially related to the amount of accumulated snow, as we found a significant correlation between the total snow in the North Alborán watershed for a year with the annual average SST of the subsequent year. A positive AO implies a colder atmosphere in the Polar Regions, which could favour occasional cold waves over the Iberian Peninsula which, when coupled with precipitations favoured by a negative NAO, may result in snow precipitation. This snow may be accumulated in the high peaks and melt down in spring-summer of the following year, which consequently increases the runoff of freshwater to the sea, which in turn causes a diminution of sea surface salinity and density, and blocks the local upwelling of colder water, resulting in a higher SST.
Conservation of energy and Gauss Bonnet gravity
Christophe Real
Physics , 2006,
Abstract: It is shown how can be made the classification of all tensors constructed from the Riemann tensor that verify the conservation of gravitational energy momentum. More precisely we explain that there exists a unique tensor of degree n in the Riemann tensor and its contractions that verifies the conservation of energy. We show that this tensor, only because it obeys this degree n structure as well as energy conservation, two facts which are true in all dimensions, verifies in dimension 2n this striking particularity of being Euler gravity. We stick here to the case n=2 but explain briefly why the general case is similar.
Tensorial Quantum Gravity and the Cosmological Constant Problem
Christophe Real
Physics , 2007,
Abstract: In the present article, which is the first part of a work in three parts, we build an equation of quantum gravity. This equation is tensorial, is equivalent to general relativity in vacuum, but differs completely from general relativity inside matter. This new equation possesses a dimensionless gravitational coupling constant, and passes all experimental tests that also passes general relativity. This quantum gravity and general relativity diverge essentially in the domain of cosmology : we prove that quantum gravity gives the solution to the whole set of problems left over by the standard cosmological model based on general relativity. Essentially, we prove that the initial singularity, the big bang, is smoothed out by quantum gravity, that the flatness problem finds a precise solution : quantum gravity predicts that Omega should be just a little greater than 1, which fits perfectly with the observed 1.02. The cosmological constant problem finds also its solution since we prove that the Lambda term does not come from any dark energy, but comes from nonperturbative quantum corrections to classical relativity, and has the exact tiny but strictly positive value needed. Furthermore, the quantum equation of gravity possesses, with no further efforts, features of unification. Indeed, our equation governs at the same time the large scale of the universe, as did general relativity, but also the structure of particles.
Numerical Correpondences between the physical Constants
Christophe Real
Physics , 2008,
Abstract: We present here a note which synthesizes our previous ideas concerning some problems in cosmology, and the numerical correspondences between the physical constants that we could deduce.
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