32 research outputs found

    Assessing hydromorphological and floristic patterns along a regulated Mediterranean river : The Serpis River (Spain)

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    In the European context, several methodologies have been developed to assess the ecological status and, specifically, the hydromorphological status of running surface waters. Although these methodologies have been widely used, few studies have focused on hydrologically altered water bodies and the factors that may determine their status. In this study, the Serpis River was divided into 16 segments from the Beniarr'es dam (40 km from the river mouth) to the sea, all of which are affected by flow regulation, but with different severity. In each segment, an inventory of the flora was conducted, and hydromorphological indices (QBR, Riparian Habitat Quality Index; and IHF, River Habitat Index) were applied. The objectives of the study were (A) to identify relationships between floristic composition and QBR components and (B) between instream habitat characteristics and IHF components as well as (C) to determine the main factors controlling the floristic composition and riparian habitat quality (QBR) and the factors controlling instream habitat characteristics and heterogeneity (IHF). A cluster analysis allowed grouping sites according to their floristic composition and instream habitat characteristics, and non-metric multidimensional scaling (NMDS) was used to ordinate the sites, obtaining the biotic and instream habitat characteristics, as well as the QBR and IHF subindices, which better explained the spatial patterns. Finally, a canonical correspondence analysis (CCA) with predictor variables (geographical, hydrological, geomorphological and human pressures) indicated the main factors controlling the spatial patterns of the floristic composition, instreamhabitat characteristics, riparian habitat quality and instream habitat heterogeneity. A gradient of riparian and instream habitat quality was identified. Our results suggest that physical constraints (presence of a gorge) have protected sites from severe human impacts, resulting in good ecological quality, despite hydrological alteration. This area, where there is geomorphological control, could be potentially reclassified into a different ecotype because regular monitoring could be using incorrect references for index scores, and naturally high scores could be confused with recovery from hydrological alteration or other pressures. The sites with the worst quality were near the river mouth and were characterised by an artificial and highly variable flow regime (related to large autumnal floods and frequent human-induced periods of zero flow). This artificial flow variability as well as the presence of lateral structures in the river channel and geomorphological characteristics were identified as the main factors driving the hydromorphological and floristic pattern in this regulated river.Diversas metodologías han sido desarrolladas en el contexto europeo para evaluar el estado ecológico, y específicamente el estado hidromorfológico de las aguas superficiales. Aunque éstas han sido ampliamente utilizadas, pocos estudios se han centrado en masas de agua hidrológicamente alteradas y en los factores que condicionan su estado. En este estudio, el río Serpis fue dividido en 16 segmentos desde la presa de Beniarrés (a 40 km de la desembocadura) hasta el mar, todos ellos afectados por la regulación de caudales con distinta severidad. En cada segmento se realizó un inventario florístico y se aplicaron índices hidromorfológicos (QBR, Calidad del Bosque de Ribera, e IHF, Índice de Hábitat Fluvial). Los objetivos del estudio fueron (A) identificar relaciones entre la composición florística y los componentes del QBR, (B) entre las caracteríısticas del hábitat fluvial y los componentes del IHF, (C) determinar los principales factores que controlan la composición florística y la calidad del hábitat ripario (QBR), y las características del hábitat fluvial y su heterogeneidad (IHF). Un cluster permitió agrupar los puntos de muestreo según su composición florística y las características del hábitat fluvial, y un escalado multidimensional no-métrico (NMDS) fue usado para ordenar los puntos, obteniendo las variables bióticas y características del hábitat y los subindices del QBR e IHF, respectivamente, que explicaban mejor los patrones espaciales. Finalmente, un análisis de correspondencias canónicas (CCA) con variables predictoras (geográficas, hidrológicas, geomorfológicas y presiones humanas) indicó los principales factores que controlan los patrones espaciales de la composición florística, las características del hábitat fluvial, la calidad del hábitat ripario y la heterogeneidad del hábitat fluvial. Se identificó un gradiente de calidad del hábitat ripario y fluvial. Los resultados sugieren que las limitaciones físicas (presencia de un cañón) han protegido a los tramos de impactos humanos severos, resultando en una buena calidad ecológica a pesar de la alteración hidrológica. Esta zona podría potencialmente ser reclasificada en un ecotipo diferente, ya que un monitoreo regular podría estar usando referencias incorrectas para los índices y sus altas puntuaciones naturales se podrían estar confundiendo con una recuperación de la alteración hidrológica o de otras presiones. Los puntos de muestreo con peor calidad estuvieron cerca de la desembocadura y tuvieron un régimen de caudales alterado y muy variable. Esta variabilidad artificial del caudal, junto con la presencia de estructuras laterales en el cauce y las características geomorfológicas fueron identificadas como los principales factores determinantes del patrón hidromorfológico y florístico en este río regulado

    Correlación en triatlón masculino entre fases y resultado inal en los JJOO de Pekin 2008

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    Introduction: Triathlon is a sport that is composed of the combination of three phases of competition. The most widespread triathlon is the Olympic, and is used in the Olympic Games, consists of swim, 1.5 km, bike 40 km and run 10 km. Aims: To determine the influence of the duration and order of the phases with the final result of the test in the male triathlon in the Olympic Games Beijing 2008. Method: We analyzed the data of 50 athletes who finished. Results and conclusions: The final result is not determined by the order of the phases, nor by the duration of these, the least influential phase has been Bike with rs = .039; p = .351; Being the one that has occupied the most time with 52.55%; The most influential phase was the Run phase with rs = .991; and p = .000; and R2 = .982 and with duration 30.21%.Introducción: El triatlón es un deporte que se compone de la combinación de tres fases de competición. La modalidad de triatlón más extendida es la olímpica, y es utilizada en los Juegos Olímpicos (JJOO), se compone de nado 1,5 km, bicicleta 40 km y carrera 10 km. Objetivos: Determinar la influencia de la duración y orden de las fases con el resultado final de la prueba en el triatlón masculino en los JJOO Pekín 2008. Método: Se analizaron los datos de 50 deportistas que finalizaron. Resultados y conclusiones: El resultado final no viene determinado ni por el orden de las fases, ni por la duración de estas, la fase menos influyente ha sido Bike con rs= 0,039; p =0,351; siendo la que más tiempo ha ocupado con un 52,55%; la fase más influyente ha sido la fase Run con rs=0,991; y p=0,000; y R2=0,982 y con duración 30,21%

    Bringing the margin to the focus: 10 challenges for riparian vegetation science and management

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    [EN] Riparian zones are the paragon of transitional ecosystems, providing critical habitat and ecosystem services that are especially threatened by global change. Following consultation with experts, 10 key challenges were identified to be addressed for riparian vegetation science and management improvement: (1) Create a distinct scientific community by establishing stronger bridges between disciplines; (2) Make riparian vegetation more visible and appreciated in society and policies; (3) Improve knowledge regarding biodiversity¿ ecosystem functioning links; (4) Manage spatial scale and context-based issues; (5) Improve knowledge on social dimensions of riparian vegetation; (6) Anticipate responses to emergent issues and future trajectories; (7) Enhance tools to quantify and prioritize ecosystem services; (8) Improve numerical modeling and simulation tools; (9) Calibrate methods and increase data availability for better indicators and monitoring practices and transferability; and (10) Undertake scientific validation of best management practices. These challenges are discussed and critiqued here, to guide future research into riparian vegetation.COST Action CONVERGES, Grant/Award Number: CA16208; Horizon 2020 Framework Programme of the European Union; Portuguese Foundation for Science and Technology, Grant/Award Number: 2020/03356/CEECIND;PTDC/ASP-SIL/28593/2017;UIDB/00239/2020; CSIC: PTIECOBIODIVRodríguez-González, PM.; Abraham, E.; Aguiar, F.; Andreoli, A.; Bale Entiene, L.; Berisha, N.; Bernez, I.... (2022). Bringing the margin to the focus: 10 challenges for riparian vegetation science and management. Wiley Interdisciplinary Reviews Water. 9(5):1-14. https://doi.org/10.1002/wat2.16041149

    Diet quality index as a predictor of treatment efficacy in overweight and obese adolescents: The EVASYON study

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    Background & aim: A diet quality index (DQI) is a tool that provides an overall score of an individual''s dietary intake when assessing compliance with food-based dietary guidelines. A number of DQIs have emerged, albeit their associations with health-related outcomes are debated. The aim of the present study was to assess whether adherence to dietary intervention, and the overall quality of the diet, can predict body composition changes. Methods: To this purpose, overweight/obese adolescents (n = 117, aged: 13–16 years; 51 males, 66 females) were recruited into a multi-component (diet, physical activity and psychological support) family-based group treatment programme. We measured the adolescents’ compliance and body composition at baseline and after 2 months (intensive phase) and 13 months (extensive phase) of follow-up. Also, at baseline, after 6 months, and at the end of follow-up we calculated the DQI. Results: Global compliance with the dietary intervention was 37.4% during the intensive phase, and 14.3% during the extensive phase. Physical activity compliance was 94.1% at 2-months and 34.7% at 13months and psychological support compliance were growing over the intervention period (10.3% intensive phase and 45.3% during extensive phase). Adolescents complying with the meal frequency criteria at the end of the extensive phase had greater reductions in FMI z-scores than those did not complying (Cohen''s d = 0.53). A statistically significant association was observed with the diet quality index. DQI-A variation explained 98.1% of BMI z-score changes and 95.1% of FMI changes. Conclusions: We conclude that assessment of changes in diet quality could be a useful tool in predicting body composition changes in obese adolescents involved in a diet and physical activity intervention programme backed-up by psychological and family support

    Seven decades of hydrogeomorphological changes in a near‐natural (Sense River) and a hydropower‐regulated (Sarine River) pre‐Alpine river floodplain in Western Switzerland

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    This is the peer reviewed version which has been published in final form at https://doi.org/10.1002/esp.5017 . This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.Hydropower alteration of the natural flow and sediment regime can severely degrade hydromorphology, thereby threatening biodiversity and overall ecosystem processes of rivers and their floodplains. Using sequences of aerial images, we quantified seven decades (1938/1942–2013) of spatiotemporal changes in channel and floodplain morphology, as well as changes in the physical habitats, of three floodplain river reaches of the Swiss pre‐Alps, two hydropower‐regulated and one near‐natural. In the Sarine River floodplain, within the first decades of hydropower impairment, the magnitude and frequency of flood events (Q2, Q10, Q30) decreased substantially. As a result, the area of pioneer floodplain habitats that depend on flood activity and sediment dynamic, such as bare sediments, decreased dramatically by approximately 95%. However, by 2013 vegetated areas had generally increased in comparison to the pre‐regulation period in 1943, indicating general vegetative colonization. Between 1943 and 2013, the active channel underwent essential narrowing (up to 62% width reduction in the residual flow reach) and habitat turnover rates were very low (5% of the total floodplain area changed habitat type five to six times). In contrast, from the 1950s onwards, the near‐natural floodplain of the Sense River experienced recurrent narrowing and widening, and frequent changes between bare and vegetated areas, reflecting the shifting habitat mosaic concept typical for natural floodplains. In the three reaches investigated, we found that the active floodplain width and erosion of vegetated areas were primarily controlled by medium to large floods (Q10, Q30), which combined with reduced time intervals between ordinary floods ≥ Q2 most likely mobilized streambed sediments and limited the ability of vegetation to establish itself on bare gravel bars within the parafluvial zone. These findings can contribute to restoration action plans such as controlled flooding and sediment replenishments in the Sarine and other floodplain rivers of the Alps

    Reasons for facebook usage: Data from 46 countries

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    Seventy-nine percent of internet users use Facebook, and on average they access Facebook eight times a day (Greenwood et al., 2016). To put these numbers into perspective, according to Clement (2019), around 30% of the world\u2019s population uses this Online Social Network (OSN) site. Despite the constantly growing body of academic research on Facebook (Chou et al., 2009; Back et al., 2010; Kaplan and Haenlein, 2010; McAndrew and Jeong, 2012; Wilson et al., 2012; Krasnova et al., 2017), there remains limited research regarding the motivation behind Facebook use across different cultures. Our main goal was to collect data from a large cross-cultural sample of Facebook users to examine the roles of sex, age, and, most importantly, cultural differences underlying Facebook use

    Sex differences in mate preferences across 45 countries: A large-scale replication

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    Considerable research has examined human mate preferences across cultures, finding universal sex differences in preferences for attractiveness and resources as well as sources of systematic cultural variation. Two competing perspectives—an evolutionary psychological perspective and a biosocial role perspective—offer alternative explanations for these findings. However, the original data on which each perspective relies are decades old, and the literature is fraught with conflicting methods, analyses, results, and conclusions. Using a new 45-country sample (N = 14,399), we attempted to replicate classic studies and test both the evolutionary and biosocial role perspectives. Support for universal sex differences in preferences remains robust: Men, more than women, prefer attractive, young mates, and women, more than men, prefer older mates with financial prospects. Cross-culturally, both sexes have mates closer to their own ages as gender equality increases. Beyond age of partner, neither pathogen prevalence nor gender equality robustly predicted sex differences or preferences across countries

    Non-Invasive Analytical Techniques Applied to Characterize the Components of Ancient Golden Medallions

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    Abstract Background The first stable material used to create a gilded surface was gold. False gold was also found in the form of copper-zinc powders or silver covered with resin. There are various ways to make gold leaf adhere to a large surface area. The identification of the materials and processes to make the gilding and the use of non- invasive techniques for gilding study is still an open problem. The gilding of the medallions from the Mudejar palace of Sevilla Alcazar was investigated, and their components were characterised using non-invasive (in situ and laboratory) techniques such as X-ray fluorescence, μ-Raman, infrared spectroscopy, X-ray diffraction and scanning electron microscopy coupled with energy dispersive X-rays. Cross-sections of golden support were also performed and studied by SEM-EDX. Results The leaf adhered to the surface was primarily a gold alloy. However, copper, silver and zinc were also found. A layer of lead chromate with some lead sulphate was between the alloy and the support. This yellow pigment (lead chromate) and the layers of bole and white lead were characterised in cross-sections prepared from samples taken from the medallions in which the golden layer was missing. The support was composed of gypsum. Another golden layer applied in oldest time period was also found. Conclusion The non-invasive techniques provided useful information about the characterisation of the components of the golden medallions. However, complete characterisation of the medallions required the use of other techniques such as mass spectrometry and scanning electron microscopy- energy dispersive X-ray. This is the first time that lead chromate has been detected in gildings. The external gilding was applied at the beginning of the 19th century using mordant oil (linseed oil).The financial support of the Spanish Commission interministerial de Ciencia y Tecnología (CICYT) under project BIA2009-12618 and the Junta de Andalucia (TEP-6558) are also acknowledged.Peer Reviewe

    BASE DE DATOS ECO-HIDROLOGICA DE LOS RIOS DE CHILE: UNA HERRAMIENTA DE GESTION PARA LOS ECOSISTEMAS ACUATICOS ECO-HYDROLOGICAL DATABASE OF CHILEAN RIVERS: A TOOL FOR MANAGEMENT OF AQUATIC ECOSYSTEM

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    El conocimiento de las especies nativas de Chile se caracteriza por ser insuficiente, incompleto, fragmentado y poco actualizado, lo cual constituye una de las principales limitantes para desarrollar estrategias de conservación de especies o planes de conservación y recuperación de sistemas acuáticos. Lo anterior cobra mayor importancia dada la mayor presión que tienen actualmente estos ecosistemas en el país. Para paliar este vacío se ha confeccionado una Base de Datos Eco-Hidrológica de los ríos de Chile. Esta base de datos cuenta con información hidrológica, fisicoquímica de las aguas, sedimentológicas e información íctica. Esta última información se ha basado en recopilación bibliográfica de literatura referente a distribución de peces, dividida en tres niveles (I, II y III) de acuerdo al detalle y escala espacial de la información (macroescala, mesoescala y microescala, respectivamente). La Base de Datos Eco-Hidrológica confeccionada la conforman 393 estaciones fluviométricas, 361 estaciones de calidad del agua, 92 estaciones sedimentológicas y un total de 1580 registros de peces distribuidos a lo largo de todo Chile. Esta base de datos se ha integrado en la plataforma de gestión "Clasificación Eco-hidrológica de los ríos de Chile" (REC-Chile), la cual se construyó basándose en los factores medioambientales que controlan el régimen hídrico de un río. La utilización conjunta de la base de datos junto con REC-Chile permitirá desarrollar una mejor planificación y gestión de los ecosistemas acuáticos en Chile.<br>The limited knowledge of Chilean native species is one of the main constraints to develop conservation strategies for species or conservation planning and rehabilitation of aquatic ecosystems. To fill this gap it was developed an Eco-Hydro logical Database of the Chilean rivers. This database contains information about hydrology, water quality, substrate and fish information. The latter information was based on literature collection concerning on fish distribution, divided into three levels (I, II and III) according to detail and spatial scale of the information (macro, meso and microscale, respectively). The database has 393 hydro logical stations, 361 water quality stations, 92 substrate stations and a total of 1580 fish records distributed throughout Chile. This database has been integrated into the management platform «River Environmental Classification of Chilean Rivers» (REC-Chile), which was built based on environmental factors which control the hydrological pattern of a river. The joint use of the database along with REC-Chile will further develop planning and management of aquatic ecosystems in Chile

    Unravelling past flash flood activity in a forested mountain catchment of the Spanish Central System

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    International audienceFlash floods represent one of the most common natural hazards in mountain catchments, and are frequentin Mediterranean environments. As a result of the widespread lack of reliable data on past events,the understanding of their spatio-temporal occurrence and their climatic triggers remains rather limited.Here, we present a dendrogeomorphic reconstruction of past flash flood activity in the Arroyo de losPuentes stream (Sierra de Guadarrama, Spanish Central System). We analyze a total of 287 incrementcores from 178 disturbed Scots pine trees (Pinus sylvestris L.) which yielded indications on 212 growthdisturbances related to past flash flood impact. In combination with local archives, meteorological data,annual forest management records and highly-resolved terrestrial data (i.e., LiDAR data and aerial imagery),the dendrogeomorphic time series allowed dating 25 flash floods over the last three centuries, with amajor event leaving an intense geomorphic footprint throughout the catchment in 1936. The analysis ofmeteorological records suggests that the rainfall thresholds of flash floods vary with the seasonality ofevents. Dated flash floods in the 20th century were primarily related with synoptic troughs owing tothe arrival of air masses from north and west on the Iberian Peninsula during negative indices of theNorth Atlantic Oscillation. The results of this study contribute considerably to a better understandingof hazards related with hydrogeomorphic processes in central Spain in general and in the Sierra deGuadarrama National Park in particular
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