245 research outputs found
Mine soil caracterization in the coal mine dumps of As Pontes (NW Spain) during its reclamation
[Resumen] Se evalúa el estado nutritivo, condiciones de acidez y elementos potencialmente tóxicos para las plantas en los suelos de mina generados en la escombrera de la Mina Puentes (La Coruña), en actual proceso de restauración ambiental. Para ello se estudia la capacidad de intercambio catiónico, la acidez actual y potencial y la fracción metálica teóricamente biodisponible (extraída con DPTA). Los resultados muestran un amplio rango de variación en los parámetros analizados. La
calidad de material original, en concreto el contenido en S, determina los niveles de acidez actual y potencial. La CICe es, en general, baja pero no significativamente diferente de los suelos naturales de la zona. La secuencia de extracción de metales con DPTA es: Fe> >Mn> >Cu>Ni~fZn~Pb>Co>>Cd, siendo la acidez del medio el parámetro fundamental que condiciona su movilización.[Abstract] Acidity, nutrient availability and potential toxicity in the coal mine dump of As Pontes (NW Spain) are evaluated. Then, cationic exchange capacity, actual and potenctial acidity and available heavy metals (DPTA extracted) are analized. Results
show a wide variability of the spoil materials. Sulfur level in the spoils explains the different actual and potential acidity conditions. Cationic exchange capacity is low ( >Mn> >Cu>Ni~~Zn~Pb>Co>>Cd and the system acidity explains its mobilization
Composition of soil solution in the Puentes coal mine dump (NW Spain) during its reclamation
[Resumen] Se estudia la disolución de suelos de mina (obtenida por desplazamiento en columna según ADAMS, 1974) en la escombrera exterior de la explotaci6n de lignito pardo de As Pontes (La Coruña). os resultados muestran un amplio rango de variación en todos los parámetros analizados. Así podemos encontrar ambientes desde fuertemente ácidos (pH = 1.5) hasta alcalinos (pH = 8.5), asociándose los valores más bajos a materiales originales con mayor contenido en sulfuros. Los medios más ácidos son los que presentan los valores más elevados de Al, Fe y metales pesados. La conductividad eléctrica de la disoluci6n es muy elevada (superior a 500 uS cm-1), presentando una correlación muy significativa con el sulfato (r = 0.84), unión mayoritario que frecuentemente supera los 1000 mg L-l..[Abstract] Soil solution of the coal mine dump of As Pontes (NW Spain) is studied. Results show a wide variation on every parameters analized. pH values range from strong acidic (pH = 1.5) to alcaline (pH = 8.5). The lowest pH are associated to the highest sulphide content in the original wastes. The most acidic environments have the higest aluminium, iron and heavy metals levels. Electric conductivity is elevated (> 500 uS cm-1) and shows a good correlation (r = 0.84) with sulphate content, the main anion in this soil solution
Plasticity in circadian activity patterns of mesocarnivores in Southwestern Europe: implications for species coexistence
Limiting similarity theory predicts that competing species must segregate along one or more dimensions of their ecological niche in order to coexist. In predator communities, interspecific interactions are influenced by a diversity of factors; therefore, the behavioural patterns of composing species will differ due to locally adapted interactions. We deployed 32-41 camera-traps in five study areas across the Iberian Peninsula to investigate the temporal relations between mesocarnivores in SW Europe. The selection for a period of the diel cycle and plasticity in activity patterns was evaluated using the Jacobs Selection Index (JSI) and the coefficient of activity overlap ({increment}1). Furthermore, we investigated whether temporal shifts can facilitate coexistence by reducing activity overlap. Seven species of mesocarnivores were detected and were assigned into one of three behaviourally distinct groups: Diurnal (JSIday ≥ 0.8), strictly nocturnal (JSInight ≥ 0.8) or facultative nocturnal species (0.4 ≥ JSInight > 0.8). Most species exhibited substantial flexibility, which allowed them to locally adapt their foraging strategies (intraspecific {increment}1 = 0.70-0.77). Mean Δ1 from all interspecific pairwise comparisons was negatively correlated with the number of carnivore species with ≥10 detections (r -0.76, p = 0.02). Our results suggest that temporal segregation is likely to play an important role in facilitating mesocarnivore coexistence, especially with increasing community complexity, where most species' activity peaks were asynchronous. These results contribute to understanding the dynamics and behavioural strategies of coexisting mesocarnivores, crucial for forecasting the possible outcomes of conservation or management actions.This work was partially supported by a PhD grant from the Fundação para a Ciência e a Tecnologia (FCT) to PM (SFRH/BD/37795/2007) and two research projects, one from the Spanish National Plan (project ref: CGL2009-10741) funded by the Spanish Ministry of Science and Innovation and EU-FEDER funds, and another one from the Spanish Organismo Autónomo Parques Nacionales (project ref: OAPN 352/2011).Peer Reviewe
Catch me if you can: diel activity patterns of mammalian prey and predators
The activity patterns exhibited by animals are shaped by evolution, but additionally fine-tuned by flexible responses to the environment. Predation risk and resource availability are environmental cues which influence the behavioural decisions that make both predators and prey engage in activity bursts, and depending on their local importance, can be strong enough to override the endogenous regulation of an animals' circadian clock. In Southern Europe, wherever the European rabbit (Oryctolagus cuniculus) is abundant, it is the main prey of most mammalian mesopredators, and rodents are generally the alternative prey. We evaluated the bidirectional relation between the diel activity strategies of these mammalian mesopredators and prey coexisting in south-western Europe. Results revealed that even though predation risk enforced by mammalian mesocarnivores during night-time was approximately twice and five times higher than during twilight and daytime, respectively, murids consistently displayed unimodal nocturnal behaviour. Conversely, the European rabbits exhibited a bimodal pattern that peaked around sunrise and sunset. Despite the existence of some overlap between the diel rhythms of mesocarnivores and rabbits, their patterns were not synchronized. We suggest that the environmental stressors in our study areas are not severe enough to override the endogenous regulation of the circadian cycle in murids. European rabbits, however, are able to suppress their biological tendency for nocturnality by selecting a predominantly crepuscular pattern. In spite of the higher energetic input, mesocarnivores do not completely track rabbits' activity pattern. They rather track rodents' activity. We propose that these systems have probably evolved towards a situation where some degree of activity during high-risk periods benefits the overall prey population survival, while the accessibility to sufficient prey prevents predators to completely track them.This work was partially supported by a PhD grantfrom the Fundaçao para a Ciência e a Tecnologia (FCT) to PM (SFRH/BD/37795/2007) and two research projects, one from the Spanish National Plan (project ref: CGL2009-10741) funded by the Spanish Ministry of Science and Innovation and EU-FEDER funds and one from the Spanish Organismo Autónomo Parques Nacionales (project ref: OAPN352/2011).Peer Reviewe
Estimating home-range size: when to include a third dimension?
Most studies dealing with home ranges consider the study areas as if they were totally flat, working only in two dimensions, when in reality they are irregular surfaces displayed in three dimensions. By disregarding the third dimension (i.e., topography), the size of home ranges underestimates the surface actually occupied by the animal, potentially leading to misinterpretations of the animals' ecological needs. We explored the influence of considering the third dimension in the estimation of home-range size by modeling the variation between the planimetric and topographic estimates at several spatial scales. Our results revealed that planimetric approaches underestimate home-range size estimations, which range from nearly zero up to 22%. The difference between planimetric and topographic estimates of home-ranges sizes produced highly robust models using the average slope as the sole independent factor. Moreover, our models suggest that planimetric estimates in areas with an average slope of 16.3° (±0.4) or more will incur in errors ≥5%. Alternatively, the altitudinal range can be used as an indicator of the need to include topography in home-range estimates. Our results confirmed that home-range estimates could be significantly biased when topography is disregarded. We suggest that study areas where home-range studies will be performed should firstly be scoped for its altitudinal range, which can serve as an indicator for the need for posterior use of average slope values to model the surface area used and/or available for the studied animals.This work was partially supported by a research project from the Spanish National
Plan (project ref: CGL2009-10741) funded by the Spanish Ministry of Science and
Innovation and EU-FEDER funds. P. M. was supported by a Ph.D. grant from the
Fundaçao para a Ciència e a Tecnologia (FCT) (SFRH/BD/37795/2007). N. S. was partially supported by a postdoctoral grant from FCT (SFRH/BPD/26666/2006). L. M. R. was funded by a Postdoctoral fellowship from the FCT and Fundo Social Europeu (III Quadro Comunitario de Apoio) (SFRH/BPD/35842/2007) and FAPESP (Proc. Ref.: 2011/00408-4).Peer Reviewe
Efficiency of hair snares and camera traps to survey mesocarnivore populations
Mammalian carnivore communities affect entire ecosystem functioning and structure. However, their large spatial requirements, preferred habitats, low densities, and elusive behavior deem them difficult to study. In recent years, noninvasive techniques have become much more common as they can be used to monitor multiple carnivore species across large areas at a relatively modest cost. Hair snares have the potential to fulfill such requirements, but have rarely been tested in Europe. Our objective was to quantitatively assess the effectiveness of hair snares for surveying mesocarnivores in the Iberian Peninsula (Southwestern Europe), by comparison with camera-trapping. We used an occupancy modeling framework to assess method-specific detectability and occupancy estimates and hypothesized that detection probabilities would be influenced by season, sampling method, and habitat-related variables. A total of 163 hair samples were collected, of which 136 potentially belonged to mesocarnivores. Genetic identification success varied with diagnostic method: 25.2 % using mitochondrial CR, and 9.9 % using the IRBP nuclear gene. Naïve occupancy estimates were, in average, 5.3 ± 1.2 times higher with camera-trapping than with hair-snaring, and method-specific detection probabilities revealed that camera traps were, in average, 6.7 ± 1.1 times more effective in detecting target species. Overall, few site-specific covariates revealed significant effects on mesocarnivore detectability. Camera traps were a more efficient method for detecting mesocarnivores and estimating their occurrence when compared to hair snares. To improve hair snares' low detection probabilities, we suggest increasing the number of sampling occasions and the frequency at which hair snares are checked. With some refinements to increase detection rates and the success of genetic identification, hair-snaring methods may be valuable for providing deeper insights into population parameters, attained through adequate analysis of genetic information, that is not possible with camera traps.This work was partially supported by a PhD grant from the Fundação para a Ciência e a Tecnologia (FCT) to PM (SFRH/BD/37795/2007) and two research projects, one from the Spanish National Plan (project ref: CGL2009-10741) funded by the Spanish Ministry of Science and Innovation and EU-FEDER funds, and one from the Spanish Organismo Autónomo Parques Nacionales (project ref: OAPN 352/2011). PCA was supported by the Luso-American Development Foundation (FLAD) and FCT sabbatical grant SFRH/BSAB/1278/2012.Peer Reviewe
Iberian lynx conservation in Portugal: Dilemmas and solutions
A team of biologists and field assistants conducted, between January 2002 and May 2003, a survey on the status of the Iberian lynx in Portugal. The survey was performed on previously identified lynx areas, during studies carried out in the 1970-s and 1990-s Intensive search for lynx scats, for DNA analysis, and camera trapping provided a basis for identifying potential lynx areas. Over 4200 km were covered during a global searching effort of 1975 man-hours. This effort resulted in the collection of 168 potential scats that were submitted to genetic validation with no positive lynx amplifications. Camera trapping was applied in a total effort of 5647 camera days, in three lynx potential areas. No positive detections were achieved. At the same time, a study on wild rabbit distribution reveals that most historical nuclei do not support lynx viable populations. Although we can not confirm extinction, the scenario is highly pessimistic. The Iberian lynx is presently in the verge of extinction. Intensive rabbit regression and massive habitat destruction are identified as the main causes of decline in recent decades. In the Portuguese lynx historical range, we could only identify significant areas suitable for lynx in the South-eastern part of the country, particularly in the Andalusian border, where we lack on recent evidence of lynx presence. Being aware of the considerable difficulties pointed above, the ICN developed a Conservation Action Plan for the Iberian lynx in order to provide a consistent and effective approach to conserve the species in Portuguese territory. This proposal describes guidance that retains future options, provides management consistent, offers necessary flexibility, in order to achieve the maximum goal of conserving the lynx in Portugal. Conservation measures have the goal of provide guiding lines for conservations agents in order to conduct actions that can positively affect lynx and/or to help avoid negative impacts through thoughtful planning of activities. The proposal of Action Plan will be applied in all the areas located in the lynx historical distribution geographic area, that present suitable characteristics for the species presence or landscape features that can be optimize for lynx survival and that can be relevant for the species life-cycle, independently of their protection status. The goal of this plan is to apply pre-release strategic reintroduction activities to make possible, in a long-term, the reintroduction of Iberian lynx, in order to assure the viability of the species, as a fundamental element of Mediterranean ecosystems. For achieving this goal it will be necessary to establish a suitable connection between ex-situ and in-situ actions
Systematic comparison of culture media and transduction enhancers for optimised CD34⁺ cell-based retroviral gene therapy protocols
Ensayos normativos para la caracterización de patologías en pizarras para cubiertas
The pathologies formed in slate roofs are mainly due to the presence of potentially unstable minerals (iron sulfides, carbonates and organic matter). These minerals may become altered by the effect of environmental agents, once the slate roof is finished. The pathologies are mainly associated with oxidation and gypsification processes of the cited mineral phases. In this work, the potential pathologies of several Spanish roofing slates are identified, using the tests defined in the European Norms EN 12326:2005, 14147:2004 and 11597:2007.Las patologías que se originan en pizarra para cubiertas son debidas fundamentalmente a la presencia de materiales alterables (sulfuros de hierro, carbonatos y materia orgánica). Estos minerales pueden llegar a alterarse por efecto de los agentes medioambientales, una vez que la pizarra es puesta en obra. Las patologías están principalmente asociadas a procesos de oxidación y yesificación de las citadas fases minerales. En este trabajo se determinan las patologías potenciales de varias pizarras para cubiertas españolas, utilizando los ensayos definidos en las normas UNE-EN 12326:2005, 14147:2004 y 11597:2007
Tres años con adolescentes en un servicio de salud mental comunitario.
Evaluación de la asistencia a adolescentes durante tres años en el programa infanto juvenil de un servicio de salud mental comunitario. Características de la demanda, intervenciones terapéuticas realizadas y situación asistencial en la que quedan los casos
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