Ground temperatures, landforms and processes in an Atlantic mountain. Cantabrian Mountains (Northern Spain)

This research was supported by the Formación de Profesorado Universitario FPU13/05837 (Ministerio de Educación Cultura y Deporte) program, by the OAPN 053/2010 (Organismo Autónomo Parques Nacionales, MAGRAMA) project, by the I + D + I CGL2015-68144-R (Ministerio de Economia y Competitividad) project, by the Leverhulme Trust International Network Grant IN-2012-140 and the Royal Geographical Society Dudley Stamp Memorial Award.Peer reviewedPostprin

Quaternary glacial evolution in the Central Cantabrian Mountains (Northern Spain)

Peer reviewedPostprin

Environmental education and landscape leisure. Geotourist map and geomorphosites in the Picos de Europa National Park

Picos de Europa National Park is the oldest and most extensive National Park in Spain, a symbol of conservationism and management of Iberian nature. The present day use is defined by abandoned ancient traditional structures, summer livestock and mainly tourism in and around the National Park, and over the last forty years the visitors of the National Park has grown until 2 million per year. The context of the map it framed in the next questions, which places are most frequented by visitors?, what places are the most interesting to visitors?, what are visitors looking for?, and who visits the National park? The main type of visitors are mountaineers (1,5%), hikers (5), active tourists (10%), recreational tourists (66%) and students (16%). Hikers and active tourist represent the 18% of visitors to the National Park, over 120,000 visitors per year. They are, joint the monitors and teachers guiding students groups, the main objective of documents and geotouristic maps. The map has five levels of reading (planimetry, altimetry, geomorphology, human uses and tourist routes), the elements are represented by areas, patterns and symbols in colours, and the selected significant elements represent the topography, geomorphological features (glacial, karst, nivation, landslide) and human remains (mining, grazing) and routes between geomorphosites and more representative scenic view points. The interpretative geotouristic maps are useful tools to develop an approach to tourist activity and for interpret nature and landscapes from direct knowledge of the field but also they are a powerful tool for environmental educationin National Parks and Natural Protected Areas.This work was funded by the projects OAPN 053/2010 (Ministry of the Environment and Rural and Marine Environment, Spain) and the support of the Picos deEuropa National Park

Vitamin C deficiency in weanling guinea pigs: differential expression of oxidative stress and DNA repair in liver and brain

Neonates are particularly susceptible to malnutrition due to their limited reserves of micronutrients and their rapid growth. In the present study, we examined the effect of vitamin C deficiency on markers of oxidative stress in plasma, liver and brain of weanling guinea pigs. Vitamin C deficiency caused rapid and significant depletion of ascorbate (P<0·001), tocopherols (P<0·001) and glutathione (P<0·001), and a decrease in superoxide dismutase activity (P=0·005) in the liver, while protein oxidation was significantly increased (P=0·011). No changes in lipid oxidation or oxidatively damaged DNA were observed in this tissue. In the brain, the pattern was markedly different. Of the measured antioxidants, only ascorbate was significantly depleted (P<0·001), but in contrast to the liver, ascorbate oxidation (P=0·034), lipid oxidation (P<0·001), DNA oxidation (P=0·13) and DNA incision repair (P=0·014) were all increased, while protein oxidation decreased (P=0·003). The results show that the selective preservation of brain ascorbate and induction of DNA repair in vitamin C-deficient weanling guinea pigs is not sufficient to prevent oxidative damage. Vitamin C deficiency may therefore be particularly adverse during the neonatal perio

Power laws and self-similar behavior in negative ionization fronts

We study anode-directed ionization fronts in curved geometries. When the magnetic effects can be neglected, an electric shielding factor determines the behavior of the electric field and the charged particle densities. From a minimal streamer model, a Burgers type equation which governs the dynamics of the electric shielding factor is obtained. A Lagrangian formulation is then derived to analyze the ionization fronts. Power laws for the velocity and the amplitude of streamer fronts are observed numerically and calculated analytically by using the shielding factor formulation. The phenomenon of geometrical diffusion is explained and clarified, and a universal self-similar asymptotic behavior is derived.Comment: 25 pages, 9 figure

Assessment of aerobic biodegradation of lower-chlorinated benzenes in contaminated groundwater using field-derived microcosms and compound-specific carbon isotope fractionation

Biodegradation of lower chlorinated benzenes (tri-, di- and monochlorobenzene) was assessed at a coastal aquifer contaminated with multiple chlorinated aromatic hydro- carbons. Field-derived microcosms, established with groundwater from the source zone and amended with a mixture of lower chlorinated benzenes, evidenced biodegradation of monochlorobenzene (MCB) and 1,4-dichlorobenzene (1,4-DCB) in aerobic microcosms, whereas the addition of lactate in anaerobic microcosms did not enhance anaerobic reduc- tive dechlorination. Aerobic microcosms established with groundwater from the plume consumed several doses of MCB and concomitantly degraded the three isomers of dichloroben- zene with no observable inhibitory effect. In the light of these results, we assessed the applicability of compound stable isotope analysis to monitor a potential aerobic remediation treatment of MCB and 1,4-DCB in this site. The carbon isotopic fractionation factors ( ε) obtained from field-derived microcosms were -0.7 ¿ ± 0.1 ¿ and -1.0 ¿ ± 0.2 ¿ for MCB and 1,4-DCB, respectively. For 1,4-DCB, the carbon isotope fractionation during aerobic biodegra- dation was reported for the first time. The weak carbon isotope fractionation values for the aerobic pathway would only allow tracing of in situ degradation in aquifer parts with high extent of biodegradation. However, based on the carbon isotope effects measured in this and previous studies, relatively high carbon isotope shifts (i.e., δ13 C > 4.0 ¿ ) of MCB or 1,4- DCB in contaminated groundwater would suggest that their biodegradation is controlled by anaerobic reductive dechlorination

Pleistocene glacial fluctuations and chronology in the Pas Mountains (Cantabrian Mountains)

RESUMEN. En este trabajo se muestra la evolución de los glaciares de las Montañas de Pas, en la Cordillera Cantábrica Oriental. Se han realizado una cartografía geomorfológica, análisis morfoestratigráfico, prospección eléctrica y sísmica y dataciones en turberas intramorrénicas y till. El complejo morrénico externo (F-I) muestra una edad para la máxima extensión glaciar anterior a 29.1509-28.570 cal a BP. En todo el macizo se ha detectado un segundo avance y equilibrio glaciar (F-II), con sus frentes en posiciones cercanas a la fase anterior. Por último, dos fases (F-III y F-IV) se caracterizaron por la presencia de glaciares muy pequeños, alojados en los circos. La última fase de equilibrio glaciar se ha atribuido a las fases tardías del Pleistoceno, coetáneas o anteriores al Tardiglaciar. Las dataciones realizadas en las Montañas Pasiegas son acordes con dataciones previas realizadas en otros macizos de la Cordillera Cantábrica y confirma la existencia de un máximo glaciar local anterior al LGM Europeo.ABSTRACT. This paper analyses the glacial evolution of the Pas Mountains, in the Eastern Cantabrian Mountains, the glacial landforms and deposits by geomorphological mapping, electric and seismic surveys, and dating intramorainic peat bog and till deposits. The external morainic complex (S-I) shows a glacial extension maximum before 29.150-28.570 cal a BP. A second glacial advance and equilibrium (S-II) have been studied in the entire massif, with glaciers reaching similar positions to the previous phase. Finally, two phases (S-III and S-IV) with very small glaciers developed in the cirque. The last equilibrium glacial phase has been attributed to Late Pleistocene cold phases, previous to Tardiglacial ones. Dating in the Pas Mountains are in agreement with previous dating in the Cantabrian Range and bears out the existence of a glacial maximum, previous to the European LGM