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Justo J.L.,University of Seville | Durand P.,University of Seville | Vazquez M.,University of Seville | Morales A.,University of Seville | Jimenez F.A.,Egmasa
Dams and Reservoirs under Changing Challenges - Proceedings of the International Symposium on Dams and Reservoirs under Changing Challenges - 79 Annual Meeting of ICOLD, Swiss Committee on Dams | Year: 2011

An original model for the dry closure of Almagrera tailings dam is being developed. This model includes the cleaning of the neighbouring Las Viñas mine. The toxic coarse Las Viñas material, deposited in waste embankments, is being thrown on the tailings inside the reservoir. A preliminary model has been presented by Justo et al. (2010). With this tool, the first closure phase has been successfully completed and is described here. A detailed study of cap and landscaping of the cleaned Las Viñas area will be undertaken, seismic calculations will be improved and the behaviour of large mobilized masses of fluidized soils, as it has happened in catastrophic tailings dams' failures, will be introduced in the model. © 2011 Taylor & Francis Group. Source

Perez J.M.,University of Jaen | Serrano E.,Autonomous University of Barcelona | Gonzalez-Candela M.,University of Murcia | Leon-Vizcaino L.,University of Murcia | And 6 more authors.
Wildlife Biology | Year: 2011

Factors affecting horn size in wild Caprinae are of biological and socio-economic interest because several species are selectively harvested on the basis of this heritable character. We analysed temporal trends in horn size in two mountain ungulates from south-eastern Spain, the Iberian wild goat Capra pyrenaica and the aoudad Ammotragus lervia. Trophy harvest is the main way in which these two species are exploited, although "poor-quality" aoudads are also selectively removed. In recent years, both populations have suffered drastic decreases in number due to outbreaks of sarcoptic mange that led to the suspension of hunting for several years. Horn length in harvested male wild goats and aoudads declined during our study period. Over an 18-year period, the mean age of male goats shot as trophies rose by four years, while the age of trophy-harvested aoudads decreased by around six months over a 9-year period. Age and environmental conditions during the first few years of life explained 20% of variance in horn size in Iberian wild goat and 53% in aoudad. Population density early in life explained much of the reduction in goat horn size over time. Nevertheless, the major fall in population densities after the sarcoptic mange outbreaks did not lead to a recovery in horn size in either species. We suggest that the selective removal of large-horned animals may contribute to a decline in horn size. Other factors that may also explain the observed pattern include changes in interspecific competition, long-lasting maternal effects and reduced carrying capacity due to overgrazing during high density periods. Unfortunately, our data sets did not allow us to account for the possible effects of these factors. © Wildlife Biology, NKV. Source

Sarasa M.,University of Jaen | Sarasa M.,French National Institute for Agricultural Research | Serrano E.,Autonomous University of Barcelona | Perez J.M.,University of Jaen | And 4 more authors.
Journal of Zoology | Year: 2010

Sperm competition is a powerful evolutionary force, and understanding the factors that regulate testes characteristics may lead to a better understanding of the variability in male reproductive success. We explored the effects of age, body condition and season on relative testes mass in the Iberian ibex Capra pyrenaica. We analysed the variability of testes mass from 175 individuals, using a model selection approach based on Akaike's information criterion corrected for a small sample size. The results suggest that season, age and body condition influenced relative testes mass. Allocation to testes mass was greatest in the rutting season (autumn) and at ages that are associated with a subordinate status and a coursing, rather than mate-guarding, reproductive strategy. In addition, males in good condition had relatively heavier testes than those in poor condition. Thus, testes mass in Iberian ibex is governed by multiple factors, and this study leads to a better understanding of gonad plasticity in this polygamous ungulate. The effect of age matches the predictions from theoretical studies on sperm competition, which suggests greater allocation to testes in disadvantaged males. © 2010 The Authors. Journal compilation © 2010 The Zoological Society of London. Source

Rezinciuc S.,Real Jardin Botanico CSIC | Galindo J.,Egmasa | Montserrat J.,Parc Natural de la Zona Volcanica de la Garrotxa | Dieguez-Uribeondo J.,Real Jardin Botanico CSIC
Fungal Biology | Year: 2014

Aphanomyces astaci (Oomycetes) is responsible for the crayfish plague disease. This species is endemic of North America and five genotypes have been described using RAPD-PCR. The red swamp crayfish, Procambarus clarkii, is one of the most widely spread North American species and invasive in the world. However, no outbreaks on its specific genotype, i.e., genotype D, have ever been described in nature. We investigated three major series of crayfish plague outbreaks in indigenous crayfish populations of Austropotamobius pallipes, located in the areas of influence of P. clarkii. All samples collected tested positive for A. astaci using a rnDNA ITS-PCR test. We also performed an AFLP-PCR analysis on 19 isolates, and found that all isolates belong to genotype D. These isolates exhibited similar properties, i.e., adaptation to warm temperatures. We demonstrate, for the first time, the transmission of A. astaci genotype D to indigenous European populations of crayfish, and confirm that the properties of adaptation to warm water temperatures seem to be a specific character of genotype D. The results of this work emphasize once more the need of controlling invasive species and its trade, since they can carry harmful pathogens with specific adaptations or increased virulence in new environments. © 2013. Source

Garcia-de-Lomas J.,Egmasa | Dana E.D.,Egmasa | Lopez-Santiago J.,Propuesta de Actuaciones para la Conservacion del Salinete en Andalucia | Gonzalez R.,Egmasa | And 2 more authors.
Aquatic Invasions | Year: 2010

The Chinese mitten crab Eriocheir sinensis was first recorded in the Guadalquivir Estuary in 1987. Management actions by the Andalusian Regional Government were implemented in 2001 to contain and reduce the population of this invasive crab in the estuary and also to prevent its dispersal to neighbouring natural protected areas. Our results showed a heterogeneous distribution of the mitten crabs in the estuary, concentrated in the Sevilla port area. The catch-per-unit-effort (CPUE) in traps was significantly higher in October-April. Annual CPUE decreased from 0.04 crabs net-1d-1 to minimum values of 0.006 crabs net-1d-1 in 2008, thus reducing the dispersal potential to neighbouring areas. However, given that a number of stochastic factors may be involved in fluctuations in population size and that ships' ballast water remains uncontrolled, the management of E. sinensis needs to be continued. Based on the results obtained and the expected sequence of the invasion process in the Guadalquivir Estuary, we propose further management improvements. These results may help to optimize the management of this invasive species both in the Guadalquivir estuary and in comparable scenarios in different parts of the world. © 2010 The Author(s). Source

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