46 research outputs found

    Gestión y Mantenimiento Parque Natural del Moncayo, acondicionamiento de senderos para uso general.

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    Practicas realizadas para el gobierno de Aragón, trabajando sobre el Parque Natural del Moncayo. Este trabajo consiste en ver detenidamente como se esta realizando la gestión del Parque Natural y en concreto en analizar y acondicionar 4 rutas senderistas señalando en cada una de ella una serie de puntos de interés que pueden ser interesantes para los usuarios de este espacio natural

    Climate and population: risk exposure to precipitation concentration in mainland Spain (1950-2010)

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    The term risk exposure combines the notions of natural hazard and the human exposure to that hazard. Spatial and temporal variations in risk exposure, therefore, can be caused by changes in hazard, in expo sure, or both. In this work a novel methodology for computing and representing risk exposure and its temporal changes are presented, and applied to the analysis of risk exposure to extreme rainfall in mainland Spain between 1950 and 2010. For that, two com plementary high-resolution gridded datasets, one of population potentials and another one of precipitation concentration, are combined. Despite a great spatial variability over time, the highest exposure was consistently found in the surrounding areas of t he largest cities and along the Mediterranean coast. The relative influence of population changes and precipitation concentration evolution is analyzed. Results suggest that hazard (precipitation concentration) changes led most of the observed changes in risk exposure, except in those decades where population movements were massive and widespread. El término exposición al riesgo combina las nociones de peligro natural y exposición humana a ese peligro. Las variaciones espaciales y temporales en esa exposición al riesgo, por tanto, pueden ser causadas por cambios en el peligro, la exposición, o en ambos. En este trabajo, se presenta una novedosa metodología para el cálculo y representación de la exposición al riesgo y sus cambios a lo largo del tiempo, aplicada al análisis de la exposición al riesgo de la precipitación extrema en la España peninsular entre 1950 y 2010. Para ello, se combinan dos bases de datos complementarias de alta resolución, una de potenciales de población y otra de concentración de la precipitación. A pesar de la gran variabilidad espacial a lo largo del tiempo, la exposición más alta se encontró de manera consistente en el entorno de las grandes ciudades y en la costa mediterránea. Se analizó la influencia relativa, en el tiempo, de los cambios en la población y de la concentración de la precipitación. Los resultados sugieren que los cambios en el peligro (concentración de la precipitación) son responsables de la mayoría de los cambios observados en la exposición al riesgo, excepto en aquellas décadas donde los movimientos de la población fueron masivos y generalizados

    Temporal variability of the urban heat island in Zaragoza (Spain)

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    We analyse the temporal intensity and variability of the urban heat island (UHI) in the city of Zaragoza (Spain), and assess the role of wind as an important atmospheric conditioning factor. Based on the time data provided by the city’s urban mesoscale meteorological network, the temperature difference between two observatories, one urban (Plaza Santa Marta) and one located on the outskirts of the urban area (Ciudad Deportiva), was calculated for the 2015-2020 period. The results indicate that the temperature in the city centre is very frequently 1º or 2ºC higher than in the surroundings, sometimes even more than 8ºC higher. The UHI is more intense in summer (an average of 2.5ºC per hour) than in winter (an average of 2.2ºC per hour) and more intense during the night than during the day. The maximum UHI value is reached in calm atmospheric situations; however, this value is very limited with winds over 10 km/h and it practically disappears with wind speeds over 50 km/h.En este artículo se analiza la intensidad y la variabilidad temporal de la isla de calor urbana (ICU) de la ciudad de Zaragoza (España) y se evalúa la acción del viento como importante factor atmosférico condicionante de la misma. A partir de los datos horarios proporcionados por la red meteorológica urbana de mesoescala de la ciudad, se calculó la diferencia de temperatura entre dos observatorios, uno urbano (Plaza Santa Marta) y otro en las afueras del área urbana (Ciudad Deportiva), en el periodo 2015-2020. Los resultados indican que la temperatura en el centro de la ciudad es, con mucha frecuencia, 1º o 2ºC más elevada que en el entorno, y en ocasiones ha llegado a superar los 8ºC. La ICU es más intensa en verano (promedios horarios de 2,5ºC) que en invierno (promedio de 2,2ºC) y es más intensa durante la noche que durante el día. El valor máximo de la ICU se alcanza en situaciones de calma atmosférica; en cambio, se debilita claramente con vientos de más de 10 km/h y llega prácticamente a desaparecer con velocidades superiores a 50 km/

    Contrasting Patterns of Tree Growth of Mediterranean Pine Species in the Iberian Peninsula

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    Wood formation is the primary biological process through which carbon is durably sequestered in woody plants, and is thus a major contributor to mitigate climate change. We analyzed the tree growth patterns of four conifer species across the Iberian Peninsula (IP) based on a dense dendrochronological network (179 sites) combined with a high resolution climate dataset. Generalized linear-mixed models were used to predict the potential tree growth of different pine species under different climate conditions considering different age classes. We found a strong age dependency of tree growth, significant variations across the climate gradients, and a significant interaction of both age and climate effects on the four species considered. Overall, Pinus halepensis was the species with the highest climate sensitivity and the highest growth rates in all age classes and across its distribution area. Due to its stronger plastic character and its potential adaptability, Pinus halepensis was demonstrated to be the most suitable species in terms of tree growth and potentiality to enhance carbon sequestration in the IP. Since its potential distribution largely exceeds its actual distribution, P. halepensis arises as a key species to cope with future climate conditions and to keep fixing carbon regardless of the climatic circumstances

    When Density Matters: The Spatial Balance between Early and Latewood

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    Understanding the influence of the current climate on the distribution, composition, and carbon storage capacity of Mediterranean tree species is key to determining future pathways under a warmer and drier climate scenario. Here, we evaluated the influence of biotic and environmental factors on earlywood (EW) and latewood (LW) growth in Aleppo pine (Pinus halepensis Mill.). Our investigation was based on a dense dendrochronological network (71 sites), which covered the entire distribution area of the species in the Iberian Peninsula (around 119.652 km2), and a high-resolution climate dataset of the Western Mediterranean area. We used generalized linear-mixed models to determine the spatial and temporal variations of EW and LW across the species distribution. Our results showed an intense but differentiated climatic influence on both EW and LW growth components. The climatic influence explained significant variations across the environmental gradients in the study area, which suggested an important adaptation through phenotypic plasticity and local adaptation to varying climatic conditions. In addition, we detected a clear spatial trade-off between efficiency and safety strategy in the growth patterns across the species distribution. Additionally, in more productive areas, the trees presented a higher proportion of EW (more efficient to water transport), while, in more xeric conditions, the LW proportion increased (more safety to avoid embolisms), implying an adaptation to more frequent drought episodes and a higher capacity of carbon depletion. We therefore concluded that Mediterranean forests adapted to dryer conditions might be more efficient as carbon reservoirs than forests growing in wetter areas. Finally, we advocated for the need to consider wood density (EW/LW proportion) when modeling current and future forest carbon sequestrations

    Missing rings in Pinus halepensis

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    Climate predictions for the Mediterranean Basin include increased temperatures, decreased precipitation, and increased frequency of extreme climatic events (ECE). These conditions are associated with decreased tree growth and increased vulnerability to pests and diseases. The anatomy of tree rings responds to these environmental conditions. Quantitatively, the width of a tree ring is largely determined by the rate and duration of cell division by the vascular cambium. In the Mediterranean climate, this division may occur throughout almost the entire year. Alternatively, cell division may cease during relatively cool and dry winters, only to resume in the same calendar year with milder temperatures and increased availability of water. Under particularly adverse conditions, no xylem may be produced in parts of the stem, resulting in a missing ring (MR). A dendrochronological network of Pinus halepensis was used to determine the relationship of MR to ECE. The network consisted of 113 sites, 1,509 trees, 2,593 cores, and 225,428 tree rings throughout the distribution range of the species. A total of 4,150 MR were identified. Binomial logistic regression analysis determined that MR frequency increased with increased cambial age. Spatial analysis indicated that the geographic areas of south-eastern Spain and northern Algeria contained the greatest frequency of MR. Dendroclimatic regression analysis indicated a non-linear relationship of MR to total monthly precipitation and mean temperature. MR are strongly associated with the combination of monthly mean temperature from previous October till current February and total precipitation from previous September till current May. They are likely to occur with total precipitation lower than 50 mm and temperatures higher than 5°C. This conclusion is global and can be applied to every site across the distribution area. Rather than simply being a complication for dendrochronology, MR formation is a fundamental response of trees to adverse environmental conditions. The demonstrated relationship of MR formation to ECE across this dendrochronological network in the Mediterranean basin shows the potential of MR analysis to reconstruct the history of past climatic extremes and to predict future forest dynamics in a changing climate

    Bacterial Mucosal Immunotherapy with MV130 Prevents Recurrent Wheezing in Children: A Randomized, Double-Blind, Placebo-controlled Clinical Trial.

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    The authors thank the patients and their families for participating in this study. They are grateful to the members of the David Sancho laboratory, especially to Carlos del Fresno, for helpful critical discussion.Rationale: Recurrent wheezing in children represents a severe public health concern. Wheezing attacks (WA), mainly associated with viral infections, lack effective preventive therapies. Objectives: To evaluate the efficacy and safety of mucosal sublingual immunotherapy based on whole inactivated bacteria (MV130) in preventing WA in children. Methods: A Phase 3 randomized, double-blind, placebo-controlled, parallel-group trial including a cohort of 120 children <3 years old with ⩾3 WA during the previous year was conducted. Children with a positive skin test to common aeroallergens in the area where the clinical trial was performed were excluded from the trial. Subjects received MV130 or placebo daily for 6 months. The primary endpoint was the number of WA within 1 year after the first dose comparing MV130 and placebo. Measurements and Main Results: There was a significant lower number of WA in MV130 versus the placebo group, 3.0 (interquartile range [IQR], 2.0-4.0) versus 5.0 (IQR, 3.0-7.0) (P < 0.001). As secondary outcomes, a decrease in the duration of WA and a reduction in symptoms and medication scores in the MV130 versus placebo group were found. No adverse events were reported related to the active treatment. Conclusions: Mucosal bacterial immunotherapy with MV130 shows safety and clinical efficacy against recurrent WA in children.Clinical trial registered with www.clinicaltrials.gov (NCT01734811).S

    Women with psychotic episodes during pregnancy show increased markers of placental damage with Tenney-Parker changes

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    y. Psychosis is a hazardous and functionally disruptive psychiatric condition which may affect women in pregnancy, entailing negative consequences for maternofetal well-being. The precise pathophysiological basis and consequences of a psychotic episode in pregnancy remain to be further elucidated. The placenta is a pivotal tissue with many functions in the gestational period, critically influencing the fate and development of pregnancy. Although detrimental alterations have been observed in women undergoing severe psychiatric disorders in pregnancy, there are little studies evaluating the consequences of suffering from a psychotic episode in the placental tissue In this work, we have evaluated the histopathological consequences of a first episode of psychosis in pregnancy (FE-PW; N=22) and compare them with healthy pregnant women (HC-PW; N=20) by using histological, immunohistochemical and gene expression techniques. Our results define that the placental tissue of FE-PW display an increase in the number of placental villi, bridges, syncytial knots and syncytial knots/villi. Besides, we have also observed an enhanced gene and protein expression in FE-PW of the hypoxic marker HIF-1α, together with the apoptotic markers BAX and Bcl-2. To our knowledge, this is the first study demonstrating significant histopathological changes in the placenta of women suffering a new-onset psychotic episode in pregnancy. Further studies should be aimed at deepening the knowledge about the pernicious effects of psychosis in the maternofetal tissues, as well as the potential implications of these alterations
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