Spatial structure of deciduous forest stands with contrasting human influence in northwest Spain

Five contrasting deciduous forest stands were studied to characterize the spatial structural variability in human-influenced forests. These stands are representative of cultural forest types widely represented in western Europe: one plantation, two coppices, one wood-pasture forest and one high forest stand. All stems with DBH > 5 cm were measured and mapped, and stem DBH distributions, spatial structure of DBH, spatial point patterns and spatial associations were analysed. Spatial autocorrelation for DBH was calculated with Moran’s I correlograms and semivariograms. Complete spatial randomness hypothesis for spatial point patterns, and both independence and random labelling hypotheses for spatial associations were analysed using Ripley’s K function. The results showed that tree sizes were conditioned by particular former management systems, which determined unimodal symmetric, positively skewed or compound DBH distributions. Spatial structure was more complex when human influence became reduced. Coppice stands showed clumped spatial patterns and independence among size classes, as a consequence of sexual and vegetative establishment of new stems in open areas. The largest clumping intensity was observed in the wood-pasture with an intermediate disturbance frequency and low inter-tree competition. The high forest stand displayed spatial traits consistent with the gap-dynamics paradigm, such as clumping of smaller trees, random arrangement of larger trees, negative association between juveniles and adults, and high structural heterogeneity. It can be expected that after cessation of human interference, coppices and wood-pastures would evolve to a more heterogeneous structure, probably with a higher habitat and species diversity.This research was partially supported by the Consejería de Medio Ambiente del Principado de Asturias (SV-PA-00-01).Peer reviewe

Big data analytics in intensive care units: challenges and applicability in an Argentinian hospital

In a typical intensive care unit of a healthcare facilities, many sensors are connected to patients to measure high frequency physiological data. Currently, measurements are registered from time to time, possibly every hour. With this data lost, we are losing many opportunities to discover new patterns in vital signs that could lead to earlier detection of pathologies. The early detection of pathologies gives physicians the ability to plan and begin treatments sooner or potentially stop the progression of a condition, possibly reducing mortality and costs. The data generated by medical equipment are a Big Data problem with near real-time restrictions for processing medical algorithms designed to predict pathologies. This type of system is known as realtime big data analytics systems. This paper analyses if proposed system architectures can be applied in the Francisco Lopez Lima Hospital (FLLH), an Argentinian hospital with relatively high financial constraints. Taking into account this limitation, we describe a possible architectural approach for the FLLH, a mix of a local computing system at FLLH and a public cloud computing platform. We believe this work may be useful to promote the research and development of such systems in intensive care units of hospitals with similar characteristics to the FLLH.Facultad de Informátic

Big data analytics in intensive care units: challenges and applicability in an Argentinian hospital

In a typical intensive care unit of a healthcare facilities, many sensors are connected to patients to measure high frequency physiological data. Currently, measurements are registered from time to time, possibly every hour. With this data lost, we are losing many opportunities to discover new patterns in vital signs that could lead to earlier detection of pathologies. The early detection of pathologies gives physicians the ability to plan and begin treatments sooner or potentially stop the progression of a condition, possibly reducing mortality and costs. The data generated by medical equipment are a Big Data problem with near real-time restrictions for processing medical algorithms designed to predict pathologies. This type of system is known as realtime big data analytics systems. This paper analyses if proposed system architectures can be applied in the Francisco Lopez Lima Hospital (FLLH), an Argentinian hospital with relatively high financial constraints. Taking into account this limitation, we describe a possible architectural approach for the FLLH, a mix of a local computing system at FLLH and a public cloud computing platform. We believe this work may be useful to promote the research and development of such systems in intensive care units of hospitals with similar characteristics to the FLLH.Facultad de Informátic

Spatio-temporal variation of early wood vessel features of Quercus robur L. along a climatic gradient in the northwestern iberian peninsula

Comunicación presentada en Rovaniemi (Finlandia) los días 13-18 de junio de 2010.Common European oak (Quercus robur L.) reaches its southwestern distribution limit in Europe close to the Northwestern Iberian Peninsula, where the transition to Mediterranean vegetation results in a progressive substitution of this species as xeric conditions increase. For this reason, xylem adaptations to drought conditions are relevant for the survival of these oaks, while their analysis by means of dendrochronological techniques can be useful to study their behavior in changing environments. For this work, we selected a network of 12 sites distributed all along Galicia (NW Spain), trying to characterize the transition to the Mediterranean climate within the region. Earlywood vessels were measured for 10 trees per site for a common period of 20 years, and combined into several growth variables combining vessel size and numbers (mean and maximum vessel area, number of vessels, total conductive area and conductivity), also considering the position within the ring. We used these data to build chronologies for each growth variable and site, which were compared by multivariate techniques. The results showed that vessel characteristics varied among sites according to the prevailing conditions along the gradient. Similarly, the comparison of time series provided a more detailed picture of the influence of climate on the adaptations of xylem anatomy. In summary, this works constitutes one of the first attempts to apply quantitative tree- ring anatomy to a network of site chronologies, and can be of relevance to the study of global chang

Análisis de la señal climática en cronologías de Fagus sylvatica y Quercus robur en la región central de la Cornisa Cantábrica

Ponencia presentada en: V Congreso Internacional de la Asociación Española de Climatología celebrado en Zaragoza del 18 al 21 de septiembre de 2006.[ES]Se analizaron las respuestas climáticas de tres cronologías de Fagus sylvatica y tres de Quercus robur en la región central de la Cornisa Cantábrica. Se utilizaron datos climáticos regionales y el índice de Oscilación del Atlántico Norte (NAO) como predictores climáticos. Las correlaciones mayores y más extensas en el tiempo se obtuvieron entre cronologías de la misma especie y similar altitud. El 37-50% de la variación del crecimiento fue explicada por el clima regional, mientras que la NAO explicó un 13-26%. La elevada temperatura estival del año previo al crecimiento y la baja temperatura invernal fueron factores limitantes para F. sylvatica por encima de 700 m de altitud. El crecimiento de Q. robur estuvo limitado por la elevada temperatura primaveral del año previo y por la sequía estival del año de crecimiento. Ambas especies mostraron una relación negativa con los índices NAO invernales. Estos resultados sugieren la necesidad de investigaciones más extensas sobre la respuesta climática a lo largo de la Cornisa Cantábrica.[EN]The climatic responses of three Fagus sylvatica and three Quercus robur tree-ring chronologies in the central Cantabrian region, were analysed. Regional temperature and precipitation data, and the climatic teleconnection indices of the North Atlantic Oscillation (NAO), were used as climatic predictors. Chronologies of the same species and similar altitudes showed the highest cross-correlations, which were significant at widest timescales. Between 37 to 50% of growth variance was explained by regional climate, while 13 to 26% was related to monthly NAO indices. High summer temperatures in the year prior to ring formation and low winter temperatures limited F. sylvatica growth at altitudes over 700 m. Q. robur radial growth was limited by high spring temperatures in the previous year and summer drought in the year the ring was formed. Growth of both species displayed negative relationship with winter NAO indices. The obtained results suggest that more exhaustive research, regarding the analysis of the climatic response along the complete Cantabrian region, is required.Esta investigación fue parcialmente financiada por la FICYT (PP-REC98-04) y la Consejería de Medio Ambiente del Principado de Asturias (SV-PA-00-01). VRO desarrolló la presente comunicación gracias a un contrato postdoctoral INIA-Xunta de Galicia

Comparación de la respuesta al clima de Pinus pinea y Pinus pinaster mediante análisis dendrocronológico, en el Parque Nacional das Illas Atlánticas

Ponencia presentada en: V Congreso Internacional de la Asociación Española de Climatología celebrado en Zaragoza del 18 al 21 de septiembre de 2006.[ES]Se realizó un estudio dendrocronológico de las anchuras de madera temprana, tardía y de la anchura total de los anillos de crecimiento de un total de 30 testigos extraídos de 25 individuos de Pinus pinea, y 34 testigos de 26 individuos de Pinus pinaster, localizados en la isla de Cortegada, dentro del Parque Nacional das Illas Atlánticas. Se calcularon las respectivas cronologías maestras, y se estableció la correlación de éstas con los datos de temperatura media mensual, precipitación total mensual y oscilación del Atlántico Norte (NAO). Los resultados indican que la precipitación es el factor que más influye en los patrones de crecimiento de ambas especies, y destaca la mayor sensibilidad de P. pinaster a las precipitaciones de primavera y a la sequía estival.[EN]A dendrochronological study of earlywood, latewood and total tree-ring widths have been made using 30 cores taken from 25 individuals of Pinus pinea and 34 cores of 26 individuals of Pinus pinaster , from the Cortegada island, which is part of the Atlantic Islands National Park. Master chronologies of each species were calculated, and their correlation with mean monthly temperature, total monthly precipitation and North Atlantic Oscillation (NAO) data was established. The obtained results indicate that precipitation is the most influent climatic factor on growth patterns for both species, and the higher sensitivity of P. pinaster tree-rings to spring precipitations and summer drought is remarkable

Effects of thinning intensity on radial growth patterns and temperature sensitivity in Pinus canariensis afforestations on Tenerife Island, Spain

The final publication is available at Springer via http://dx.doi.org/10.1007/s13595-011-0125-8The suitability of thinning to prevent forest growth decline from global warming has been 25 scarcely tested in the Macaronesian Canary pine (Pinus canariensis Sweet ex Spreng.). We used tree-ring series from dominant, codominant, and overtopped trees to study the 27 effects of thinning intensity on basal area increments (BAI) and climate sensitivity on windward 28 (wet) and leeward (dry) slopes on Tenerife, Canary Islands. Three replicated blocks of control, 29 light thinning, and heavy thinning stands were set on each slope in 1988, and cores were 30 extracted in 2007. Heavy thinning induced growth release and increased BAI, mainly on dominant and 32 codominant trees, whereas light thinning effects were negligible; their impacts were more intense 33 on windward. Temperature sensitivity was hardly affected by thinning on leeward, where climate 34 control was stronger. On windward, thinning enhanced the influence of summer temperatures. 35 Upper crown classes were overall more sensitive, but overtopped trees responded better in 36 summer. Thinning intensity and aspect greatly influence growth on Canary pine afforestations, but 38 individual responses are highly dependent on crown classes. In addition, thinning may be less 39 effective to modify growth conditions on leeward slopes, at least if it is not intense.We thank A. González, S. Lamas, P. Manso, I. Outeda, B. Rodríguez-Morales and A. Soliño for laboratory assistance, N. Muñoz for statistical advice, and two anonymous reviewers for providing valuable comments on the manuscript. The staff of Corona Forestal Natural Park of Tenerife facilitated site accession. We gratefully acknowledge the effort 380 of staff and technicians that designed and executed the thinning experiment in 1988. V. Rozas benefited by a visiting fellowship to the University of La Laguna, funded by Consellería de Innovación e Industria, Xunta de Galicia, and research contracts by INIA-Xunta de Galicia and 383 CSIC. This research was partially funded by Consellería de Innovación e Industria, Xunta de Galicia (PGIDIT06PXIB502262PR) and INIA, Spanish Ministry of Science and Innovation (RTA2006-00117)

Detecting Nothofagus pumilio Growth Reductions Induced by Past Spring Frosts at the Northern Patagonian Andes

Extreme climatic events, such as late frosts in spring during leaf flush, have considerable impacts on the radial growth of temperate broadleaf trees. Albeit, all broadleaved species are potentially vulnerable, damage depends on the particularities of the local climate, the species, and its phenology. The impact of late spring frosts has been widely investigated in the Northern Hemisphere, but the potential incidence in Southern Hemisphere tree species is still poorly known. Here, we reconstruct spring frost occurrence at 30 stands of the deciduous tree Nothofagus pumilio in its northern range of distribution in the Patagonian Andes. We identified tree ring-width reductions at stand level not associated with regional or local drought events, matching unusual minimum spring temperatures during leaf unfolding. Several spring frosts were identified along the northern distribution of N. pumilio, being more frequent in the more continental Argentinean forests. Spring frost in 1980 had the largest spatial extent. The spring frosts in 1980 and 1992 also induced damages in regional orchards. Spring frost damage was associated with (i) a period of unusually warm temperatures at the beginning of leaf unfolding, followed by (ii) freezing temperatures. This study helps expand our understanding of the climatic constraints that could determine the future growth and dynamics of Andean deciduous forests and the potential use of tree-rings as archives of extreme events of spring frosts in northern Patagonia.Fil: Sangüesa Barreda, Gabriel. Universidad de Valladolid; EspañaFil: Villalba, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Rozas, Vicente. Universidad de Valladolid; España. Universidad Austral de Chile; ChileFil: Christie, Duncan A.. Centro de Investigaciones sobre Clima y Resiliencia; Chile. Universidad Austral de Chile; ChileFil: Olano, José Miguel. Universidad de Valladolid; Españ