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  • Open Access English
    Authors: 
    Parera-Portell, Joan A.; Ubach, Raquel;
    Country: Spain

    This dataset contains monthly IceMap500 sea ice extent maps (March and September) from 2000 to 2019, covering the northernmost European sea regions defined by the European Union's Marine Strategy Framework Directive (MSFD), belonging to the Arctic, North-East Atlantic Ocean and the Baltic Sea. IceMap500 is a sea ice detection algorithm that generates accurate sea ice extent maps from MODIS visible and infrared data at 500 m resolution at nadir. The algorithm is built upon the previous IceMap250, and features a new method to correct artefacts in the MODIS cloud mask and additional threshold tests that allow the enlargement of the mapped area, the reduction of potential error sources and a qualitative improvement of the resulting maps. Quality assessment has shown this algorithm produces sea ice presence maps systematically achieving accuracies above 90 % (tested in the European Arctic).

  • Open Access English
    Authors: 
    Martínez Ana; Barrera-Corominas, Aleix; Cuypers, Dieter; Härkönen, Mika; Girón Domínguez, Carmen;
    Country: Spain

    The webinar 'Educational gaps and skills mismatch in the European Bioeconomy' was held on January 22nd, from 11:00 to 12:00 CET. It was coordinated by SIE and all the partners contributed with feedback and/or content. It was targeted to anyone interested in learning what the Bioeconomy is and what are the main gaps in the educational programmes related to Bioeconomy in Europe. The aim was to provide attendees with the opportunity to have an overview and hints on the importance of the European bioeconomy in our daily lives, the skills mismatch in the bioeconomy field, as well as to facilitate questions and active discussion.

  • Open Access English
    Authors: 
    Coll Brunet, Marta;
    Publisher: [Barcelona] : Universitat Autònoma de Barcelona,
    Country: Spain

    El canvi climàtic està provocant un augment de les sequeres a l'hemisferi nord, provocant episodis de declivi forestal i contribuint a la reducció de l'eficiència dels boscos per fixar carboni. Hi ha una manca d'avaluacions a escala macroecològica de les respostes dels boscos davant els episodis de sequera, incloent processos tals com defoliació, mortalitat o les respostes de les xarxes tròfiques. En el primer capítol, s'ha descrit un augment generalitzat de la defoliació dels boscos del sud d'Europa entre 1987 i 2007. En resposta a l'augment del dèficit hídric, s'ha observat un increment de la defoliació, especialment a les zones forestals més àrides. Paral·lelament, s'han observat respostes demogràfiques dels arbres. S'ha descrit com els patrons de defoliació coincideixen amb un augment de la taxa de mortalitat a les zones més seques. Aquests episodis de mortalitat han estat relacionats amb densitat dels arbres i altes temperatures. A més a més, es mostra com les sequeres extremes afecten també les comunitats de insectes i fongs, provocant efectes a llarg termini sobre les xarxes tròfiques. Els nostres resultats revelen un mosaic geogràfic molt complex, de respostes específiques de cada espècie al canvi climàtic, però amb una tendència general d'augment dels danys provocats per les sequeres. En el segon capítol hem estudiat els patrons demogràfics de les variables demogràfiques dels boscos (reclutament, creixement i mortalitat) de les principals espècies forestals d'Espanya. Hem avaluat quins són els principals factors que determinen aquestes variables demogràfiques (clima, topografia, sol, característiques del estrat arbori i característiques individuals), la seva variabilitat geogràfica i les interaccions que existeixen entre elles. La modelització en quantils ens ha permès obtenir una descripció sintètica dels gradients de les múltiples variables que afecten la demografia. A més a més, hem observat diferencies importants en les respostes demogràfiques entre els dos gèneres dominants, Quercus i Pinus. En resum, els nostres resultats sintetitzen les respostes demogràfiques dels boscos espanyols al llarg de gradients climàtics i ressalten que les interaccions més fortes entre variables s'observen als extrems dels gradients climàtics. En el tercer capítol, hem descrit els patrons a gran escala de les limitacions en els processos de reclutament dels boscos de la conca mediterrània. S'ha observat l'existència de tendències oposades en les limitacions de reclutament entre els dos generes dominants, Quercus i Pinus, i s'ha identificat els principals agents. Les espècies de Pinus pateixen importants limitacions de reclutament (63% de plots de boscos de Pinus comprat amb un 29% de plots de boscos amb espècies de Quercus). De forma molt diferent, les espècies de Quercus s'han expandit en un 41% dels plots, mentre Pinus s'ha expandit tan sols en un 10% dels plots. Bayesian structural equation models ressalten el paper principal de la presència de plançons de Quercus en la limitació del reclutament de Pinus en cinc espècies d'aquest gènere. El reclutament de Pinus sylvestris, Pinus nigra està negativament associat a la presència d'incendis. Aquest estudi identifica Quercus ilex, que és l'espècie més abundant de l'àrea d'estudi, com una agent clau que pot provocar canvis en els patrons de reclutament a gran escala, afectant negativament les espècies de pins a mesura que avança el procés de successió. Aquests resultats subratllen que la futura expansió o contracció dels boscos de Quercus ilex en un context de canvi climàtic serà un procés clau, que alhora controlarà les respostes demogràfiques de les espècies de Pi de la conca mediterrània Climate change is progressively increasing severe drought events in the Northern Hemisphere, causing regional tree die-off events and contributing to the global reduction of the carbon sink efficiency of forests. There is a critical lack of integrated communitywide assessments of drought-induced responses in forests at the macroecological scale, including defoliation, mortality, and food web responses. In the first chapter we report a generalized increase in crown defoliation in southern European forests occurring during 1987-2007. Forest tree species have consistently and significantly altered their crown leaf structures, with increased percentages of defoliation in the drier parts of their distributions in response to increased water deficit. We assessed the demographic responses of trees associated with increased defoliation in southern European forests, specifically in the Iberian Peninsula region. We found that defoliation trends are paralleled by significant increases in tree mortality rates in drier areas that are related to tree density and temperature effects. Furthermore, we show that severe drought impacts are associated with sudden changes in insect and fungal defoliation dynamics, creating long-term disruptive effects of drought on food webs. Our results reveal a complex geographical mosaic of species specific responses to climate change-driven drought pressures on the Iberian Peninsula, with an overwhelmingly predominant trend toward increased drought damage. In the second chapter we studied the geographical patterns of forest demography variables (tree recruitment, growth and mortality) of the main species in Spain and assessed their multiple ecological drivers (climate, topography, soil, forest stand attributes and tree-specific traits) as well as the geographical variability of their effects and interactions. Quantile modeling analyses allowed a synthetic description of the gradients of multiple covariates influencing forest demography in this area. These multivariate effect gradients showed significantly stronger interactions at the extremes of the rainfall gradient. Remarkably, in all demographic variables, qualitatively different levels of effects and interactions were observed across tree-size classes. In addition, significant differences in demographic responses and effect gradients were also evident between the dominant genus Quercus and Pinus. Overall, our results synthesize forest demographic responses across climatic gradients in Spain, and unveil the interactions between driving factors operating in the drier and wetter edges. In the third chapter, we described large-scale patterns of limitations in tree recruitment in the Mediterranean Basin. We unveil the existence of opposite trends of recruitment limitation between the dominant genera Quercus and Pinus on a large scale and identify the key ecological drivers of these diverging trends. Severe limitations in recruitment were observed across extensive areas in all Pinus species studied, with recruitment failure affecting 54-71% of the surveyed plots. In striking contrast, Quercus species expanded into 41% of the plots surveyed versus only 10% for Pinus and had a lower local recruitment failure (29% of Quercus localities compared to 63% for Pinus species). Bayesian structural equation models highlighted the key role of the presence of Q. ilex saplings and the increase in the basal area of Q. ilex in limiting Pinus recruitment in five Pinus species. The recruitment of P. sylvestris and P. nigra showed the most negative trends and was negatively associated with the impacts of fire. This study identified Q. ilex, the most widespread species in this area, as a key driver of recruitment shifts on a large scale, negatively affecting most pine species with the advance of forest succession. These results highlight that the future expansion/contraction of Q. ilex stands with ongoing climate change will be a key process indirectly controlling the demographic responses of Pinus species in the Mediterranean Basin.

  • Open Access English
    Authors: 
    Bachour, Dunia Antoine; Fernández Sánchez, Enrique; Universitat Autònoma de Barcelona. Departament de Física;
    Publisher: [Barcelona] : Universitat Autònoma de Barcelona,
    Country: Spain

    La medición precisa de la Irradiancia Directa Normal (DNI) es esencial para el diseño e implementación de proyectos CSP (energía solar concentrada). Qatar cuenta con abundante radiación solar; por lo tanto, el aprovechamiento de la misma es de gran interés en esta región, en particular para sistemas de concentración solar. Antes de embarcarse en dichos proyectos, se debe contar con datos de irradiancia directa normal confiables y de buena calidad. Actualmente, los mapas existentes de radiación solar en Qatar basados en mediciones a nivel de la superficie terrestre son rudimentarios. Los mapas solares basados en datos de satélite proveen una mayor cobertura espacial, pero con resoluciones espacial y temporal relativamente pobres, además de que los datos satelitales de radiaion solar aun no han sido calibrados con mediciones directas en Qatar, por lo que no proveen valores muy precisos de DNI. Por esto, datos confiables basados en mediciones directas con altas resoluciones son necesarios en regiones como Qatar, con medio ambiente desértico arenoso y con altas concentraciones de aerosoles. Dependiendo de su composición, un aerosol puede dispersar o absorber DNI. Entre más aerosoles hay presentes en el aire, mayor es la dispersión y/o absorción del componente directo de la radiación solar, lo que reduce la eficiencia de los sistemas de energía solar concentrada. Así, la calidad de la atmósfera tiene gran impacto sobre la viabilidad de las plantas CSP. El trabajo presentado en esta tesis se enfoca en el estudio del impacto de la calidad de la atmósfera en Doha, Qatar, específicamente los aerosoles, sobre la atenuación del haz solar directo. Esto se realiza por medio de una función de correlación entre la calidad atmosferica y mediciones de DNI. El resultado de esta correlación puede ser usado para calibrar mapas solares. Se utilizó un LIDAR para estimar la calidad de la atmósfera por medio de la medición de luz reflejada por los componentes de la atmósfera. Junto al LIDAR, una estación de monitoreo de la radiación solar se usó para medir directamente DNI. Con base en los resultados de este trabajo, los mapas solares de Qatar basados en satélite pueden ser corregidos, lo que permitirá la elaboración de una base de datos completa del recurso solar en Qatar. Accurate measurements of Direct Normal Irradiance (DNI) are essential to Concentrated Solar Power (CSP) project design and implementation. Qatar has an abundant supply of solar radiation; therefore, harnessing solar energy is of particular interest in this region specifically for concentrated solar power systems. Before such projects are undertaken, good quality and reliable Direct Normal Irradiance of solar radiation data must be available. Existing solar energy maps of Qatar based on ground station measurements are primitive. Solar energy maps based on satellite data have a wider spatial coverage but relatively poor temporal and spatial resolutions, and satellite-derived solar data have not been calibrated with ground measurements in Qatar, and thus cannot provide accurate DNI. Therefore, reliable data based on high resolution ground measurements are required specifically for a country like Qatar, a region of harsh desert environment with dusty climate and high aerosol loads. Depending on its composition, an aerosol can scatter and/or absorb the DNI. The more aerosols in the air, the more scattering and/or absorption of the direct component of the solar radiation will take place and this will reduce the effectiveness of a concentrated solar power system. The quality of the atmosphere has thus a great impact on the viability of CSP farms. The work presented in this thesis is focused on studying the impact of the quality of the atmosphere in Doha, Qatar, specifically aerosol particles, on the solar direct beam attenuation. This is done by establishing a correlation function between the quality of the atmosphere and the measured DNI. The result of this correlation may be used to calibrate satellite solar maps. A LIDAR device is used to estimate the quality of the atmosphere by measuring the light backscattered by the constituents of the atmosphere. Beside the LIDAR, a Ground Solar Radiation Monitoring Station is used to measure directly the DNI. Based on the result of this work, satellite-derived solar maps of Qatar can be corrected and this will allow building a comprehensive solar radiation database for Qatar.

  • Open Access English
    Authors: 
    Martínez Ana; Cuypers, Dieter; Tienda Martagón, Dulce; Barrera-Corominas, Aleix; Adamsen, Anders Peter; Tukiainen, Pauliina; Viña, Gloria de la; García Alegre, María;
    Country: Spain

    It provides stakeholders with the opportunity to get an overview and hints on the European bio-economy, the job foresight and the UrBIOfuture project's developments

  • Other research product . 2021
    Open Access English
    Authors: 
    Weber, Tina; Adăscăliței, Dragoș; Allinger, Bernadette; Van Herreweghe, Dries; Gospodinova, Zlatka Ivanova; Bejakovic, Predrag; Antoniou, Loucas; Veverkova, Soña; Randrup, Anders Gogsig; Kadarik, Ingel; +19 more
    Publisher: Luxemburg European Foundation for the Improvement of Living and Working Conditions
    Country: Spain

    Per part del QUIT com a corresponsal d'Eurofound, la contribució a l'informe ha estat feta per l'Alejandro Godino. While unemployment is still a huge challenge in Europe, some countries, sectors and occupations are experiencing labour shortages. This report explores various approaches to identifying labour shortages and maps national policy debates around the issue. It documents public and social partner interventions to tackle labour shortages, such as measures fostering geographical or occupational mobility, addressing skills shortages and underinvestment in skills, improving working and employment conditions, and providing better matching procedures.

  • Open Access English
    Authors: 
    Barangé O'Driscoll, Lara Thandi; Universitat Autònoma de Barcelona. Facultat de Ciències Polítiques i de Sociologia;
    Country: Spain

    At it's latest Conference of the Parties in November 2017, the United Nations Framework Convention on Climate Change adopting the 'Koronivia joint work on agriculture' agreement, transferring agriculture to the agenda of its two Subsidiary Bodies. This study approaches agriculture's incorporation into the Convention from the theoretical perspective of institutional interaction - a framework for understanding how one institution influences another - in order to show that the involvement of the Food and Agriculture Organization of the United Nations in the negotiations has played a decisive role in the Convention's growing consideration of agriculture.

  • Open Access English
    Authors: 
    Martínez Huerta, Borja; Universitat Autònoma de Barcelona. Departament de Microelectrònica i Sistemes Electrònics;
    Publisher: [Barcelona] : Universitat Autònoma de Barcelona,
    Country: Spain

    Estamos viviendo una nueva era, caracterizada por la omnipresencia de dispositivos inteligentes conectados a la red. En esta era, la emergencia de la llamada Internet of Things (IoT) está transformando profundamente la industria a nivel global, así como la propia vida de los seres humanos. El grado de integración alcanzado, así como su conectividad a través de internet, ha permitido que millones de dispositivos se conecten e interactúen a una escala sin precedentes. Esta diseminación generalizada de dispositivos con potencial de procesado, combinada a su capacidad sensora y comunicativa, está incrementando de forma extraordinaria el volumen de datos capturados. Como consecuencia de la expansión de la IoT, el número de dispositivos conectados esta aumentando exponencialmente y pronto ha de generar un problema de escalabilidad, problema muy ligado a su dependencia energética. Un buen número de dispositivos quedarán integrados en el entorno, en lugares inaccesibles o cuya conexión por cable suponga un coste elevado, convirtiendo la energía en un recurso muy preciado. De hecho, el cambio de baterías de miles de dispositivos es simplemente inconcebible. El coste de mantenimiento y, en general, de cualquier intervención, puede suponer un severo freno al avance de este nuevo paradigma. Por tanto, uno de los retos para hacer sostenible la masiva expansión de dispositivos sensores inalámbricos es reducir su coste en términos energéticos. Claramente, se requieren nuevos métodos para afrontar este cambio. Las correlaciones espacio-temporales son esenciales en muchos campos y, por tanto, es bastante razonable suponer que la información de contexto pueda ser también explotada en este paradigma. Partiendo de esta hipótesis, el presenta trabajo ofrece una aproximación sistemática para definir Políticas de Eficiencia Energética para dispositivos sensores inalámbricos, basada en el análisis de las Correlaciones Espacio-Temporales. Sobre esta idea, esta tesis se estructura en dos partes. En primer lugar se aborda la necesidad de un perfilado energético suficientemente preciso para sensores inalámbricos. Para este fin, se ha formalizado un modelo general de consumo que permite perfilar la gestión de energía en dispositivos integrados. Los resultados obtenidos remarcan la importancia de entender los ciclos de actividad involucrados en las tareas que ejecutan este tipo de dispositivos. La segunda parte, desarrollada en base a éste modelo, demuestra el potencial que ofrece el análisis de correlaciones espacio-temporales como herramienta para definir políticas eficientes de gestión. Esta hipótesis se ha investigado desde tres perspectivas diferentes: a) captación de la energía del entorno, b) compresión de la información y c) análisis de datos de contexto. El análisis realizado y las políticas definidas desde estas tres perspectivas proporcionan importantes reducciones tanto en términos energéticos como de coste. Como conclusión, todos los métodos estudiados han demostrado su validez en la definición y validación de políticas energéticas. Las estrategias propuestas pueden ser de gran ayuda para los ingenieros de aplicación, ya que permiten parametrizar las plataformas y explorar sus diseños en las primeras fases de desarrollo. De esta forma se puede reducir el tiempo de acceso al mercado, a la vez que se asegura un balance óptimo entre coste, funcionalidad y tiempo de vida. We are living in a new era, which is characterized by the omnipresence of smart, networked devices. The developing Internet of Things is profoundly transforming both global industry and human lives. Hardware integration, along with the ability to seamlessly communicate over the internet, has allowed millions of embedded objects to connect and interact on an unprecedented scale. The ubiquitous presence of embedded computing devices, combined with their sensing and communicating capabilities, is increasing the amounts of data captured on a massive scale. As a result of the expanding IoT, the number of connected devices is increasing exponentially and will soon generate a problem of scalability, related mostly to their energy dependence. Many devices will be embedded in the environment, in places that are inaccessible or expensive to connect with wires, making them resource-constrained. Most importantly, battery replacements for thousands of devices are inconceivable. Maintenance and intervention costs can limit the advance of this new paradigm. Therefore, one of the challenges in ensuring the massive expansion of wireless sensing devices is reducing their cost in terms of energy. Clearly, novel methods are required for addressing this change. Spatio-temporal correlations are essential in many different fields. Thus, it is quite reasonable to assume that contextual information can be exploited within this emerging paradigm. Under this hypothesis, the present study provides a systematic approach to defining Energy Efficiency Policies for Wireless Sensor Devices, based on the analysis of Spatio-Temporal Correlations. To this end, the present work is structured in two parts. First, we address the necessity of an accurate energy profiling model for wireless sensing devices. We have formalized a generic consumption model to profile the energy utilization of low-power embedded devices. The obtained results stress the importance of understanding the cycles of operation involved in embedded tasks. The second part of this dissertation demonstrates the applicability of spatio-temporal correlation analysis as a tool for defining energy efficiency policies. This hypothesis has been investigated from three different perspectives: a) energy harvesting, b) data compression and c) contextual data analysis. The correct analysis and policy definition from these three perspectives provides important energy and cost reduction opportunities. In conclusion, all the studied methods proved to be effective for defining and validating energy policies. The proposed strategies help designers to parameterize and customize platforms for their application during the design phases, and hence the time-to-market of new products is reduced while an optimal tradeoff is ensured among cost, functionality and life expectancy.

  • Open Access English
    Authors: 
    Reyes-García, Victoria; García-del-Amo, David; Benyei, Petra; Junqueira, André B.; Labeyrie, Vanesse; Li, Xiaoyue; Porcuna Ferrer, Anna; Schlingmann, Anna; Porcher, Vincent; Soleymani Fard, Ramin;
    Publisher: Universitat Autònoma de Barcelona. Institut de Ciència i Tecnologia Ambientals,
    Country: Spain

    Unidad de excelencia María de Maeztu CEX2019-000940-M This protocol has been designed to collect local perceptions of climate change impacts on climatic (e.g. rainfall patterns change), physical (e.g., shrinking glaciers), biological (e.g., phenological changes), and socioeconomic systems (e.g., crop failure due to rainfall patterns change), but also adaptations to those impacts, local agricultural calendars and local narratives to allow the reconstruction of historical and relevant events using a combination of quantitative and qualitative methodologies.

  • Open Access English
    Authors: 
    Arias Ortiz, Ariane; Masqué Barri, Pere; Glass, Leah; Benson, Lisa; Kennedy, Hilary; Duarte, Carlos M..; Garcia-Orellana, Jordi; Benitez-Nelson, Claudia; Humphries, Marc S.; Ratefinjanahary, Ismaël; +3 more
    Country: Spain

    Altres ajuts: "Obra Social la Caixa" (LCF/BQ/ES14/10320004) i Blue Forest Project Australian Research Council LIEF Project (LE170100219) Unidad de excelencia María de Maeztu MdM-2015-0552 The database compiles data (in Arias-Ortiz et al. 2020) on biogeochemical characteristics (density, organic carbon and total nitrogen, stable carbon and nitrogen isotopes and sediment grain size) of mangrove forest soils in Tsimipaika Bay, Madagascar. Pb-210 concentrations of the first 40 cm are included. The dataset compiles data for a total of 10 cores (5 cores from an intact forest and 5 from a deforested area) along with surface water dissolved organic carbon (DOC) concentrations measured at 8 stations. Enquiries about the dataset may be sent to Ariane Arias-Ortiz: aariasortiz@berkeley.edu

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12 Research products, page 1 of 2
  • Open Access English
    Authors: 
    Parera-Portell, Joan A.; Ubach, Raquel;
    Country: Spain

    This dataset contains monthly IceMap500 sea ice extent maps (March and September) from 2000 to 2019, covering the northernmost European sea regions defined by the European Union's Marine Strategy Framework Directive (MSFD), belonging to the Arctic, North-East Atlantic Ocean and the Baltic Sea. IceMap500 is a sea ice detection algorithm that generates accurate sea ice extent maps from MODIS visible and infrared data at 500 m resolution at nadir. The algorithm is built upon the previous IceMap250, and features a new method to correct artefacts in the MODIS cloud mask and additional threshold tests that allow the enlargement of the mapped area, the reduction of potential error sources and a qualitative improvement of the resulting maps. Quality assessment has shown this algorithm produces sea ice presence maps systematically achieving accuracies above 90 % (tested in the European Arctic).

  • Open Access English
    Authors: 
    Martínez Ana; Barrera-Corominas, Aleix; Cuypers, Dieter; Härkönen, Mika; Girón Domínguez, Carmen;
    Country: Spain

    The webinar 'Educational gaps and skills mismatch in the European Bioeconomy' was held on January 22nd, from 11:00 to 12:00 CET. It was coordinated by SIE and all the partners contributed with feedback and/or content. It was targeted to anyone interested in learning what the Bioeconomy is and what are the main gaps in the educational programmes related to Bioeconomy in Europe. The aim was to provide attendees with the opportunity to have an overview and hints on the importance of the European bioeconomy in our daily lives, the skills mismatch in the bioeconomy field, as well as to facilitate questions and active discussion.

  • Open Access English
    Authors: 
    Coll Brunet, Marta;
    Publisher: [Barcelona] : Universitat Autònoma de Barcelona,
    Country: Spain

    El canvi climàtic està provocant un augment de les sequeres a l'hemisferi nord, provocant episodis de declivi forestal i contribuint a la reducció de l'eficiència dels boscos per fixar carboni. Hi ha una manca d'avaluacions a escala macroecològica de les respostes dels boscos davant els episodis de sequera, incloent processos tals com defoliació, mortalitat o les respostes de les xarxes tròfiques. En el primer capítol, s'ha descrit un augment generalitzat de la defoliació dels boscos del sud d'Europa entre 1987 i 2007. En resposta a l'augment del dèficit hídric, s'ha observat un increment de la defoliació, especialment a les zones forestals més àrides. Paral·lelament, s'han observat respostes demogràfiques dels arbres. S'ha descrit com els patrons de defoliació coincideixen amb un augment de la taxa de mortalitat a les zones més seques. Aquests episodis de mortalitat han estat relacionats amb densitat dels arbres i altes temperatures. A més a més, es mostra com les sequeres extremes afecten també les comunitats de insectes i fongs, provocant efectes a llarg termini sobre les xarxes tròfiques. Els nostres resultats revelen un mosaic geogràfic molt complex, de respostes específiques de cada espècie al canvi climàtic, però amb una tendència general d'augment dels danys provocats per les sequeres. En el segon capítol hem estudiat els patrons demogràfics de les variables demogràfiques dels boscos (reclutament, creixement i mortalitat) de les principals espècies forestals d'Espanya. Hem avaluat quins són els principals factors que determinen aquestes variables demogràfiques (clima, topografia, sol, característiques del estrat arbori i característiques individuals), la seva variabilitat geogràfica i les interaccions que existeixen entre elles. La modelització en quantils ens ha permès obtenir una descripció sintètica dels gradients de les múltiples variables que afecten la demografia. A més a més, hem observat diferencies importants en les respostes demogràfiques entre els dos gèneres dominants, Quercus i Pinus. En resum, els nostres resultats sintetitzen les respostes demogràfiques dels boscos espanyols al llarg de gradients climàtics i ressalten que les interaccions més fortes entre variables s'observen als extrems dels gradients climàtics. En el tercer capítol, hem descrit els patrons a gran escala de les limitacions en els processos de reclutament dels boscos de la conca mediterrània. S'ha observat l'existència de tendències oposades en les limitacions de reclutament entre els dos generes dominants, Quercus i Pinus, i s'ha identificat els principals agents. Les espècies de Pinus pateixen importants limitacions de reclutament (63% de plots de boscos de Pinus comprat amb un 29% de plots de boscos amb espècies de Quercus). De forma molt diferent, les espècies de Quercus s'han expandit en un 41% dels plots, mentre Pinus s'ha expandit tan sols en un 10% dels plots. Bayesian structural equation models ressalten el paper principal de la presència de plançons de Quercus en la limitació del reclutament de Pinus en cinc espècies d'aquest gènere. El reclutament de Pinus sylvestris, Pinus nigra està negativament associat a la presència d'incendis. Aquest estudi identifica Quercus ilex, que és l'espècie més abundant de l'àrea d'estudi, com una agent clau que pot provocar canvis en els patrons de reclutament a gran escala, afectant negativament les espècies de pins a mesura que avança el procés de successió. Aquests resultats subratllen que la futura expansió o contracció dels boscos de Quercus ilex en un context de canvi climàtic serà un procés clau, que alhora controlarà les respostes demogràfiques de les espècies de Pi de la conca mediterrània Climate change is progressively increasing severe drought events in the Northern Hemisphere, causing regional tree die-off events and contributing to the global reduction of the carbon sink efficiency of forests. There is a critical lack of integrated communitywide assessments of drought-induced responses in forests at the macroecological scale, including defoliation, mortality, and food web responses. In the first chapter we report a generalized increase in crown defoliation in southern European forests occurring during 1987-2007. Forest tree species have consistently and significantly altered their crown leaf structures, with increased percentages of defoliation in the drier parts of their distributions in response to increased water deficit. We assessed the demographic responses of trees associated with increased defoliation in southern European forests, specifically in the Iberian Peninsula region. We found that defoliation trends are paralleled by significant increases in tree mortality rates in drier areas that are related to tree density and temperature effects. Furthermore, we show that severe drought impacts are associated with sudden changes in insect and fungal defoliation dynamics, creating long-term disruptive effects of drought on food webs. Our results reveal a complex geographical mosaic of species specific responses to climate change-driven drought pressures on the Iberian Peninsula, with an overwhelmingly predominant trend toward increased drought damage. In the second chapter we studied the geographical patterns of forest demography variables (tree recruitment, growth and mortality) of the main species in Spain and assessed their multiple ecological drivers (climate, topography, soil, forest stand attributes and tree-specific traits) as well as the geographical variability of their effects and interactions. Quantile modeling analyses allowed a synthetic description of the gradients of multiple covariates influencing forest demography in this area. These multivariate effect gradients showed significantly stronger interactions at the extremes of the rainfall gradient. Remarkably, in all demographic variables, qualitatively different levels of effects and interactions were observed across tree-size classes. In addition, significant differences in demographic responses and effect gradients were also evident between the dominant genus Quercus and Pinus. Overall, our results synthesize forest demographic responses across climatic gradients in Spain, and unveil the interactions between driving factors operating in the drier and wetter edges. In the third chapter, we described large-scale patterns of limitations in tree recruitment in the Mediterranean Basin. We unveil the existence of opposite trends of recruitment limitation between the dominant genera Quercus and Pinus on a large scale and identify the key ecological drivers of these diverging trends. Severe limitations in recruitment were observed across extensive areas in all Pinus species studied, with recruitment failure affecting 54-71% of the surveyed plots. In striking contrast, Quercus species expanded into 41% of the plots surveyed versus only 10% for Pinus and had a lower local recruitment failure (29% of Quercus localities compared to 63% for Pinus species). Bayesian structural equation models highlighted the key role of the presence of Q. ilex saplings and the increase in the basal area of Q. ilex in limiting Pinus recruitment in five Pinus species. The recruitment of P. sylvestris and P. nigra showed the most negative trends and was negatively associated with the impacts of fire. This study identified Q. ilex, the most widespread species in this area, as a key driver of recruitment shifts on a large scale, negatively affecting most pine species with the advance of forest succession. These results highlight that the future expansion/contraction of Q. ilex stands with ongoing climate change will be a key process indirectly controlling the demographic responses of Pinus species in the Mediterranean Basin.

  • Open Access English
    Authors: 
    Bachour, Dunia Antoine; Fernández Sánchez, Enrique; Universitat Autònoma de Barcelona. Departament de Física;
    Publisher: [Barcelona] : Universitat Autònoma de Barcelona,
    Country: Spain

    La medición precisa de la Irradiancia Directa Normal (DNI) es esencial para el diseño e implementación de proyectos CSP (energía solar concentrada). Qatar cuenta con abundante radiación solar; por lo tanto, el aprovechamiento de la misma es de gran interés en esta región, en particular para sistemas de concentración solar. Antes de embarcarse en dichos proyectos, se debe contar con datos de irradiancia directa normal confiables y de buena calidad. Actualmente, los mapas existentes de radiación solar en Qatar basados en mediciones a nivel de la superficie terrestre son rudimentarios. Los mapas solares basados en datos de satélite proveen una mayor cobertura espacial, pero con resoluciones espacial y temporal relativamente pobres, además de que los datos satelitales de radiaion solar aun no han sido calibrados con mediciones directas en Qatar, por lo que no proveen valores muy precisos de DNI. Por esto, datos confiables basados en mediciones directas con altas resoluciones son necesarios en regiones como Qatar, con medio ambiente desértico arenoso y con altas concentraciones de aerosoles. Dependiendo de su composición, un aerosol puede dispersar o absorber DNI. Entre más aerosoles hay presentes en el aire, mayor es la dispersión y/o absorción del componente directo de la radiación solar, lo que reduce la eficiencia de los sistemas de energía solar concentrada. Así, la calidad de la atmósfera tiene gran impacto sobre la viabilidad de las plantas CSP. El trabajo presentado en esta tesis se enfoca en el estudio del impacto de la calidad de la atmósfera en Doha, Qatar, específicamente los aerosoles, sobre la atenuación del haz solar directo. Esto se realiza por medio de una función de correlación entre la calidad atmosferica y mediciones de DNI. El resultado de esta correlación puede ser usado para calibrar mapas solares. Se utilizó un LIDAR para estimar la calidad de la atmósfera por medio de la medición de luz reflejada por los componentes de la atmósfera. Junto al LIDAR, una estación de monitoreo de la radiación solar se usó para medir directamente DNI. Con base en los resultados de este trabajo, los mapas solares de Qatar basados en satélite pueden ser corregidos, lo que permitirá la elaboración de una base de datos completa del recurso solar en Qatar. Accurate measurements of Direct Normal Irradiance (DNI) are essential to Concentrated Solar Power (CSP) project design and implementation. Qatar has an abundant supply of solar radiation; therefore, harnessing solar energy is of particular interest in this region specifically for concentrated solar power systems. Before such projects are undertaken, good quality and reliable Direct Normal Irradiance of solar radiation data must be available. Existing solar energy maps of Qatar based on ground station measurements are primitive. Solar energy maps based on satellite data have a wider spatial coverage but relatively poor temporal and spatial resolutions, and satellite-derived solar data have not been calibrated with ground measurements in Qatar, and thus cannot provide accurate DNI. Therefore, reliable data based on high resolution ground measurements are required specifically for a country like Qatar, a region of harsh desert environment with dusty climate and high aerosol loads. Depending on its composition, an aerosol can scatter and/or absorb the DNI. The more aerosols in the air, the more scattering and/or absorption of the direct component of the solar radiation will take place and this will reduce the effectiveness of a concentrated solar power system. The quality of the atmosphere has thus a great impact on the viability of CSP farms. The work presented in this thesis is focused on studying the impact of the quality of the atmosphere in Doha, Qatar, specifically aerosol particles, on the solar direct beam attenuation. This is done by establishing a correlation function between the quality of the atmosphere and the measured DNI. The result of this correlation may be used to calibrate satellite solar maps. A LIDAR device is used to estimate the quality of the atmosphere by measuring the light backscattered by the constituents of the atmosphere. Beside the LIDAR, a Ground Solar Radiation Monitoring Station is used to measure directly the DNI. Based on the result of this work, satellite-derived solar maps of Qatar can be corrected and this will allow building a comprehensive solar radiation database for Qatar.

  • Open Access English
    Authors: 
    Martínez Ana; Cuypers, Dieter; Tienda Martagón, Dulce; Barrera-Corominas, Aleix; Adamsen, Anders Peter; Tukiainen, Pauliina; Viña, Gloria de la; García Alegre, María;
    Country: Spain

    It provides stakeholders with the opportunity to get an overview and hints on the European bio-economy, the job foresight and the UrBIOfuture project's developments

  • Other research product . 2021
    Open Access English
    Authors: 
    Weber, Tina; Adăscăliței, Dragoș; Allinger, Bernadette; Van Herreweghe, Dries; Gospodinova, Zlatka Ivanova; Bejakovic, Predrag; Antoniou, Loucas; Veverkova, Soña; Randrup, Anders Gogsig; Kadarik, Ingel; +19 more
    Publisher: Luxemburg European Foundation for the Improvement of Living and Working Conditions
    Country: Spain

    Per part del QUIT com a corresponsal d'Eurofound, la contribució a l'informe ha estat feta per l'Alejandro Godino. While unemployment is still a huge challenge in Europe, some countries, sectors and occupations are experiencing labour shortages. This report explores various approaches to identifying labour shortages and maps national policy debates around the issue. It documents public and social partner interventions to tackle labour shortages, such as measures fostering geographical or occupational mobility, addressing skills shortages and underinvestment in skills, improving working and employment conditions, and providing better matching procedures.

  • Open Access English
    Authors: 
    Barangé O'Driscoll, Lara Thandi; Universitat Autònoma de Barcelona. Facultat de Ciències Polítiques i de Sociologia;
    Country: Spain

    At it's latest Conference of the Parties in November 2017, the United Nations Framework Convention on Climate Change adopting the 'Koronivia joint work on agriculture' agreement, transferring agriculture to the agenda of its two Subsidiary Bodies. This study approaches agriculture's incorporation into the Convention from the theoretical perspective of institutional interaction - a framework for understanding how one institution influences another - in order to show that the involvement of the Food and Agriculture Organization of the United Nations in the negotiations has played a decisive role in the Convention's growing consideration of agriculture.

  • Open Access English
    Authors: 
    Martínez Huerta, Borja; Universitat Autònoma de Barcelona. Departament de Microelectrònica i Sistemes Electrònics;
    Publisher: [Barcelona] : Universitat Autònoma de Barcelona,
    Country: Spain

    Estamos viviendo una nueva era, caracterizada por la omnipresencia de dispositivos inteligentes conectados a la red. En esta era, la emergencia de la llamada Internet of Things (IoT) está transformando profundamente la industria a nivel global, así como la propia vida de los seres humanos. El grado de integración alcanzado, así como su conectividad a través de internet, ha permitido que millones de dispositivos se conecten e interactúen a una escala sin precedentes. Esta diseminación generalizada de dispositivos con potencial de procesado, combinada a su capacidad sensora y comunicativa, está incrementando de forma extraordinaria el volumen de datos capturados. Como consecuencia de la expansión de la IoT, el número de dispositivos conectados esta aumentando exponencialmente y pronto ha de generar un problema de escalabilidad, problema muy ligado a su dependencia energética. Un buen número de dispositivos quedarán integrados en el entorno, en lugares inaccesibles o cuya conexión por cable suponga un coste elevado, convirtiendo la energía en un recurso muy preciado. De hecho, el cambio de baterías de miles de dispositivos es simplemente inconcebible. El coste de mantenimiento y, en general, de cualquier intervención, puede suponer un severo freno al avance de este nuevo paradigma. Por tanto, uno de los retos para hacer sostenible la masiva expansión de dispositivos sensores inalámbricos es reducir su coste en términos energéticos. Claramente, se requieren nuevos métodos para afrontar este cambio. Las correlaciones espacio-temporales son esenciales en muchos campos y, por tanto, es bastante razonable suponer que la información de contexto pueda ser también explotada en este paradigma. Partiendo de esta hipótesis, el presenta trabajo ofrece una aproximación sistemática para definir Políticas de Eficiencia Energética para dispositivos sensores inalámbricos, basada en el análisis de las Correlaciones Espacio-Temporales. Sobre esta idea, esta tesis se estructura en dos partes. En primer lugar se aborda la necesidad de un perfilado energético suficientemente preciso para sensores inalámbricos. Para este fin, se ha formalizado un modelo general de consumo que permite perfilar la gestión de energía en dispositivos integrados. Los resultados obtenidos remarcan la importancia de entender los ciclos de actividad involucrados en las tareas que ejecutan este tipo de dispositivos. La segunda parte, desarrollada en base a éste modelo, demuestra el potencial que ofrece el análisis de correlaciones espacio-temporales como herramienta para definir políticas eficientes de gestión. Esta hipótesis se ha investigado desde tres perspectivas diferentes: a) captación de la energía del entorno, b) compresión de la información y c) análisis de datos de contexto. El análisis realizado y las políticas definidas desde estas tres perspectivas proporcionan importantes reducciones tanto en términos energéticos como de coste. Como conclusión, todos los métodos estudiados han demostrado su validez en la definición y validación de políticas energéticas. Las estrategias propuestas pueden ser de gran ayuda para los ingenieros de aplicación, ya que permiten parametrizar las plataformas y explorar sus diseños en las primeras fases de desarrollo. De esta forma se puede reducir el tiempo de acceso al mercado, a la vez que se asegura un balance óptimo entre coste, funcionalidad y tiempo de vida. We are living in a new era, which is characterized by the omnipresence of smart, networked devices. The developing Internet of Things is profoundly transforming both global industry and human lives. Hardware integration, along with the ability to seamlessly communicate over the internet, has allowed millions of embedded objects to connect and interact on an unprecedented scale. The ubiquitous presence of embedded computing devices, combined with their sensing and communicating capabilities, is increasing the amounts of data captured on a massive scale. As a result of the expanding IoT, the number of connected devices is increasing exponentially and will soon generate a problem of scalability, related mostly to their energy dependence. Many devices will be embedded in the environment, in places that are inaccessible or expensive to connect with wires, making them resource-constrained. Most importantly, battery replacements for thousands of devices are inconceivable. Maintenance and intervention costs can limit the advance of this new paradigm. Therefore, one of the challenges in ensuring the massive expansion of wireless sensing devices is reducing their cost in terms of energy. Clearly, novel methods are required for addressing this change. Spatio-temporal correlations are essential in many different fields. Thus, it is quite reasonable to assume that contextual information can be exploited within this emerging paradigm. Under this hypothesis, the present study provides a systematic approach to defining Energy Efficiency Policies for Wireless Sensor Devices, based on the analysis of Spatio-Temporal Correlations. To this end, the present work is structured in two parts. First, we address the necessity of an accurate energy profiling model for wireless sensing devices. We have formalized a generic consumption model to profile the energy utilization of low-power embedded devices. The obtained results stress the importance of understanding the cycles of operation involved in embedded tasks. The second part of this dissertation demonstrates the applicability of spatio-temporal correlation analysis as a tool for defining energy efficiency policies. This hypothesis has been investigated from three different perspectives: a) energy harvesting, b) data compression and c) contextual data analysis. The correct analysis and policy definition from these three perspectives provides important energy and cost reduction opportunities. In conclusion, all the studied methods proved to be effective for defining and validating energy policies. The proposed strategies help designers to parameterize and customize platforms for their application during the design phases, and hence the time-to-market of new products is reduced while an optimal tradeoff is ensured among cost, functionality and life expectancy.

  • Open Access English
    Authors: 
    Reyes-García, Victoria; García-del-Amo, David; Benyei, Petra; Junqueira, André B.; Labeyrie, Vanesse; Li, Xiaoyue; Porcuna Ferrer, Anna; Schlingmann, Anna; Porcher, Vincent; Soleymani Fard, Ramin;
    Publisher: Universitat Autònoma de Barcelona. Institut de Ciència i Tecnologia Ambientals,
    Country: Spain

    Unidad de excelencia María de Maeztu CEX2019-000940-M This protocol has been designed to collect local perceptions of climate change impacts on climatic (e.g. rainfall patterns change), physical (e.g., shrinking glaciers), biological (e.g., phenological changes), and socioeconomic systems (e.g., crop failure due to rainfall patterns change), but also adaptations to those impacts, local agricultural calendars and local narratives to allow the reconstruction of historical and relevant events using a combination of quantitative and qualitative methodologies.

  • Open Access English
    Authors: 
    Arias Ortiz, Ariane; Masqué Barri, Pere; Glass, Leah; Benson, Lisa; Kennedy, Hilary; Duarte, Carlos M..; Garcia-Orellana, Jordi; Benitez-Nelson, Claudia; Humphries, Marc S.; Ratefinjanahary, Ismaël; +3 more
    Country: Spain

    Altres ajuts: "Obra Social la Caixa" (LCF/BQ/ES14/10320004) i Blue Forest Project Australian Research Council LIEF Project (LE170100219) Unidad de excelencia María de Maeztu MdM-2015-0552 The database compiles data (in Arias-Ortiz et al. 2020) on biogeochemical characteristics (density, organic carbon and total nitrogen, stable carbon and nitrogen isotopes and sediment grain size) of mangrove forest soils in Tsimipaika Bay, Madagascar. Pb-210 concentrations of the first 40 cm are included. The dataset compiles data for a total of 10 cores (5 cores from an intact forest and 5 from a deforested area) along with surface water dissolved organic carbon (DOC) concentrations measured at 8 stations. Enquiries about the dataset may be sent to Ariane Arias-Ortiz: aariasortiz@berkeley.edu

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