101 research outputs found

    Long-Term Tree Regeneration of Fragmented Agroforestry Systems Under Varying Climatic Conditions

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    Iberian dehesas and montados are agroforestry systems protected by the European Habitats Directive due to high levels of biological diversity associated to their savannah-like structure. Tree scattering in dehesas, montados and other agroforestry systems is, however, known to compromise tree regeneration, although recent work suggests that it may protect tree populations from climate warming by alleviating plant-plant competition. We analyze how climatic conditions, tree isolation and their interactions influence the outcomes of regeneration stages, from flower production to early seedling establishment, using data gathered during the long-term monitoring (2001–2018) of ca. 300 Holm oak Quercus ilex trees located in central Spain. Holm oak reproductive effort, predispersal seed losses, and early seedling recruitment were sensitive to climate change, especially to year-round drought. Effort and early seedling recruitment decreased, while abortion and predispersal seed predation increased, with higher drought intensity. Spring warming increases pollination effectiveness, but had no further effect on acorn crops. Forest clearing seemed to have little scope to ameliorate these negative effects, as shown by weak or no interactive effects between the spatial configuration of trees (cover or isolation) and climate variables (spring temperature or drought intensity). Forest opening aimed at decreasing adult tree mortality under climate change scenarios would then have little or no effects on tree recruitment. Landscape-scale rotations alternating shrub encroachment and thinning along periods adapted to changing climate are proposed as the main management option to preserve both oak forests and dehesas in the long term.Fil: Díaz, Mario. Consejo Superior de Investigaciones Científicas. Museo Nacional de Ciencias Naturales; EspañaFil: Sánchez Mejía, Teresa. Consejo Superior de Investigaciones Científicas. Museo Nacional de Ciencias Naturales; EspañaFil: Morán López, Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin

    Potencialidad del enfoque de los servicios de los ecosistemas para la protección de la agricultura en la ordenación territorial

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    El modelo de dominación absoluta de las aglomeraciones urbanas sobre el campo ha entrado en crisis y también lo está haciendo el sistema agroalimentario globalizado, por su insostenibilidad, su injusticia y su incapacidad para asegurar la calidad de los alimentos producidos. Para llegar a definir un nuevo modelo más equilibrad, es necesario cambiar la percepción que se tiene de lo rural, superando la actual visión consumista y utilitarista, reconociendo el papel mucho más amplio que desempeña para la calidad de vida en la ciudad. En esta recomposición del modelo territorial cobran singular importancia los espacios periurbanos, por su condición de interfaz de encuentro entre lo rural y lo urbano

    Behavioural complementarity among frugivorous birds and lizards can promote plant diversity in island ecosystems

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    The behavioural complementarity of fruit-eating animals is thought to exert a key role in plant community assembly. However, a mechanistic understanding of the causal links between the two processes is still lacking. This study assesses whether complementarity between dispersers in feeding and microhabitat-use behaviour enhances community-scale dispersal services, resulting in a more diverse community of seedlings. We used a Bayesian approach to connect a comprehensive database of seed dispersal effectiveness at a community scale with a transition probability model that accounts for behavioural complementarity. Our model system was the thermosclerophyllous shrubland of the Canary Islands. There, fleshy-fruited plants rely on two types of frugivores: lizards and birds. Lizards consumed all plant species and preferentially used open areas, whereas birds foraged for small single-seeded fruits and dispersed their seeds beneath plants. Through feeding on different sets of plants, they generated a rich seed-rain community. By diversifying the microhabitat of deposition, more species could find suitable recruitment sites. Distinct foraging and microhabitat-use choices led to complementary dispersal services. Lizards ensured that all plant species were present in the seedling community, while birds promoted a more even distribution of them. As a result, diversity in the community of seedlings was enhanced. Overall, our work underscores that behavioural complementarity promotes diversity in the early-regenerating plant communities. These enhanced dispersal services rely on the presence of all functional groups. Thus, in communities where frugivores display unique behaviours, preserving a diverse community of dispersers should be a conservation target. A free Plain Language Summary can be found within the Supporting Information of this article.Fil: Morán López, Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: González Castro, Aarón. Island Ecology and Evolution Research Group ; Argentina. Consejo Superior de Investigaciones Científicas; EspañaFil: Morales, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Nogales, Manuel. Island Ecology and Evolution Research Group ; Argentina. Consejo Superior de Investigaciones Científicas; Españ

    Estudio a nivel de perfil para el diseño del sistema de agua potable barrio Farabundo Martí, Comarca el Chagüe León Nicaragua

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    Presenta el diseño de un mini acueducto por bombeo eléctrico MABE en el barrio Farabundo Martí se realizó estudio para determinación de la demanda existente de la población como diagnóstico de la situación actual un estudio técnico para la localización y un estudio socio económico para la evaluación del proyecto mediante la relación de costo beneficio

    Ungulate presence and predation risks reduce acorn predation by mice in dehesas

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    Foraging decisions by rodents are key for the long-term maintenance of oak populations in which avian seed dispersers are absent or inefficient. Decisions are determined by the environmental setting in which acorn-rodent encounters occur. In particular, seed value, competition and predation risks have been found to modify rodent foraging decisions in forest and human-modified habitats. Nonetheless, there is little information about their joint effects on rodent behavior, and hence, local acorn dispersal (or predation). In this work, we manipulate and model the mouse-oak interaction in a Spanish dehesa, an anthropogenic savanna system in which nearby areas can show contrasting levels of ungulate densities and antipredatory cover. First, we conducted a large-scale cafeteria field experiment, where we modified ungulate presence and predation risk, and followed mouse foraging decisions under contrasting levels of moonlight and acorn availability. Then, we estimated the net effects of competition and risk by means of a transition probability model that simulated mouse foraging decisions. Our results show that mice are able to adapt their foraging decisions to the environmental context, affecting initial fates of handled acorns. Under high predation risks mice foraged opportunistically carrying away large and small seeds, whereas under safe conditions large acorns tended to be predated in situ. In addition, in the presence of ungulates lack of antipredatory cover around trees reduced mice activity outside tree canopies, and hence, large acorns had a higher probability of survival. Overall, our results point out that inter-specific interactions preventing efficient foraging by scatter-hoarders can reduce acorn predation. This suggests that the maintenance of the full set of seed consumers as well as top predators in dehesas may be key for promoting local dispersal.Fil: Morán López, Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Sánchez Dávila, Jesús. Consejo Superior de Investigaciones Científicas. Museo Nacional de Ciencias Naturales; EspañaFil: Torre, Ignasi. Museu de Ciències Naturals de Granollers; EspañaFil: Navarro Castilla, Alvaro. Universidad Autónoma de Madrid; EspañaFil: Barja, Isabel. Universidad Autónoma de Madrid; EspañaFil: Diaz, Mario. Consejo Superior de Investigaciones Científicas. Museo Nacional de Ciencias Naturales; Españ

    Propuesta de formación en centros para comunidades de aprendizaje

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    En el presente trabajo tratamos de definir una estrategia para la formación del profesorado dentro de los centros educativos que inicien y desarrollen una Comunidad de Aprendizaje, orientada a la implementación de una metodología de formación en centros cuya finalidad es la mejora del desarrollo de las actividades de los grupos interactivos dentro de dicha Comunidad. El principio del proyecto se encuentra en las probabilidades reales de mejora en la aplicación de esta metodología, que vendrá dada por las personas/profesionales involucrados en las Comunidades de Aprendizaje, siendo ellas las que mejor puedan transmitir, percibir, aprender y evaluar su propia formación, y crear nuevas metodologías a través del diálogo. Este trabajo se ha desarrollado gracias a un proceso de colaboración entre nuestra facultad y varios centros públicos que se han constituido como Comunidades de Aprendizajes para la superación de desigualdades y mejorar el aprendizaje del alumnado.In this study we try to define a strategy for teacher training within schools which begin and develop Learning Community aimed at the implementation of a training methodology in centres whose aim is the improvement of the development of the activities of the interactive groups within that community. The principle of the project is real chance of improvement in the application of this methodology, that it will come given by the people/professionals involved in learning communities, and they that can best convey, perceive, learn and assess their own training, and create new methodologies through dialogue. This work has been developed through a process of collaboration between our faculty and various public facilities that have been constituted as learning communities for the overcoming of inequalities and improve the learning of students

    Host-guest interactions between cyclodextrins and surfactants with functional groups at the end of the hydrophobic tail

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    The aim of this work was to investigate the influence of the incorporation of substituents at the end of the hydrophobic tail on the binding of cationic surfactants to α-, β-, and -cyclodextrins. The equilibrium binding constants of the 1:1 inclusion complexes formed follow the trend K1(α-CD)>K1(β-CD)>>K1(-CD), which can be explained by considering the influence of the CD cavity volume on the host-guest interactions. From the comparison of the K1 values obtained for dodecyltriethylammonium bromide, DTEAB, to those estimated for the surfactants with the substituents, it was found that the incorporation of a phenoxy group at the end of the hydrocarbon tail does not affect K1, and the inclusion of a naphthoxy group has some influence on the association process, slightly diminishing K1. This makes evident the importance of the contribution of hydrophobic interactions to the binding, the length of the hydrophobic chain being the key factor determining K1. However, the presence of the aromatic rings does influence the location of the host and the guest in the inclusion complexes. The observed NOE interactions between the aromatic protons and the CD protons indicate that the aromatic rings are partially inserted within the host cavity, with the cyclodextrin remaining close to the aromatic rings, which could be partially intercalated in the host cavity. To the authors´ knowledge this is the first study on the association of cyclodextrins with monomeric surfactants incorporating substituents at the end of the hydrophobic tai

    Effect of the comprehensive smoke-free law on time trends in smoking behaviour in primary healthcare patients in Spain: a longitudinal observational study

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    Objective: This study aimed to analyse the impact of comprehensive smoke-free legislation (SFL) on the prevalence and incidence of adult smoking in primary healthcare (PHC) patients from three Spanish regions, overall and stratified by sex. Design: Longitudinal observational study conducted between 2008 and 2013. Setting: 66 PHC teams in Catalonia, Navarre and the Balearic Islands (Spain). Participants: Population over 15 years of age assigned to PHC teams. Primary and secondary outcomes measures: Quarterly age-standardised prevalence of non-smoker, smoker and ex-smoker and incidence of new smoker, new ex-smoker and ex-smoker relapse rates were estimated with data retrieved from PHC electronic health records. Joinpoint analysis was used to analyse the trends of age-standardised prevalence and incidence rates. Trends were expressed as annual percentage change and average annual percent change. Results: The overall standardised smoker prevalence rate showed a significant downward trend (higher in men than women) and the overall standardised ex-smoker prevalence rate showed a significant increased trend (higher in women than men) in the three regions. Standardised smoker and ex-smoker prevalence rates were higher for men than women in all regions. With regard to overall trends of incidence rates, new smokers decreased significantly in Catalonia and Navarre and similarly in men and women, new ex-smokers decreased significantly and more in men in Catalonia and the Balearic Islands, and ex-smoker relapse increased in Catalonia (particularly in women) and decreased in Navarre. Conclusions: Trends in smoking behaviour in PHC patients remain unchanged after the implementation of comprehensive SFL. The impact of the comprehensive SFL might have been lessened by the effect of the preceding partial SFL

    Habitat fragmentation is linked to cascading effects on soil functioning and CO2 emissions in Mediterranean holm-oak-forests

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    We studied key mechanisms and drivers of soil functioning by analyzing soil respiration and enzymatic activity in Mediterranean holm oak forest fragments with different influence of the agricultural matrix. For this, structural equation models (SEM) were built including data on soil abiotic (moisture, temperature, organic matter, pH, nutrients), biotic (microbial biomass, bacterial and fungal richness), and tree-structure-related (basal area) as explanatory variables of soil enzymatic activity and respiration. Our results show that increased tree growth induced by forest fragmentation in scenarios of high agricultural matrix influence triggered a cascade of causal-effect relations, affecting soil functioning. On the one hand, soil enzymatic activity was strongly stimulated by the abiotic (changes in pH and microclimate) and biotic (microbial biomass) modifications of the soil environment arising from the increased tree size and subsequent soil organic matter accumulation. Soil CO2 emissions (soil respiration), which integrate releases from all the biological activity occurring in soils (autotrophic and heterotrophic components), were mainly affected by the abiotic (moisture, temperature) modifications of the soil environment caused by trees. These results, therefore, suggest that the increasing fragmentation of forests may profoundly impact the functioning of the plant-soil-microbial system, with important effects over soil CO2 emissions and nutrient cycling at the ecosystem level. Forest fragmentation is thus revealed as a key albeit neglected factor for accurate estimations of soil carbon dynamics under global change scenarios

    Effect of the comprehensive smoke-free law on time trends in smoking behaviour in primary healthcare patients in Spain : A longitudinal observational study

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    Altres ajuts: Funding This project has been funded by the Carlos III Health Institute through the Network for Prevention and Health Promotion in Primary Care (redIAPP, RD12/0005/0001; RD16/0007/0001), and by European Union ERDF funds.Objective This study aimed to analyse the impact of comprehensive smoke-free legislation (SFL) on the prevalence and incidence of adult smoking in primary healthcare (PHC) patients from three Spanish regions, overall and stratified by sex. Design Longitudinal observational study conducted between 2008 and 2013. Setting 66 PHC teams in Catalonia, Navarre and the Balearic Islands (Spain). Participants Population over 15 years of age assigned to PHC teams. Primary and secondary outcomes measures Quarterly age-standardised prevalence of non-smoker, smoker and ex-smoker and incidence of new smoker, new ex-smoker and ex-smoker relapse rates were estimated with data retrieved from PHC electronic health records. Joinpoint analysis was used to analyse the trends of age-standardised prevalence and incidence rates. Trends were expressed as annual percentage change and average annual percent change. Results The overall standardised smoker prevalence rate showed a significant downward trend (higher in men than women) and the overall standardised ex-smoker prevalence rate showed a significant increased trend (higher in women than men) in the three regions. Standardised smoker and ex-smoker prevalence rates were higher for men than women in all regions. With regard to overall trends of incidence rates, new smokers decreased significantly in Catalonia and Navarre and similarly in men and women, new ex-smokers decreased significantly and more in men in Catalonia and the Balearic Islands, and ex-smoker relapse increased in Catalonia (particularly in women) and decreased in Navarre. Conclusions Trends in smoking behaviour in PHC patients remain unchanged after the implementation of comprehensive SFL. The impact of the comprehensive SFL might have been lessened by the effect of the preceding partial SFL
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