121 research outputs found

    Els faigs es defensen del canvi climàtic

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    Investigadors del Centre de Recerca Ecològica i Aplicacions Forestals (CREAF), del CSIC i de la Universitat Autònoma de Barcelona han descobert que les poblacions de faigs mostren capacitat d'adaptar-se a l'escalfament climàtic que estem vivint. En particular, han observat que cada cop hi ha més fagedes adaptades a temperatures més càlides. No està clar, però, que aquesta capacitat d'adaptació permeti pal·liar completament els efectes del canvi climàtic.Investigadores del Centro de Investigación Ecológica y Aplicaciones Forestales (CREAF), del CSIC y de la UAB han descubierto que las poblaciones de hayas muestran capacidad de adaptarse al calentamiento global que estamos viviendo. En particular, han observado que cada vez hay más hayedos adaptados a temperaturas más cálidas. No obstante, no está claro que esta capacidad de adaptación permita paliar completamente los efectos del cambio climático

    Refining predictions of population decline at species' rear edges

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    According to broad‐scale application of biogeographical theory, widespread retractions of species’ rear edges should be seen in response to ongoing climate change. This prediction rests on the assumption that rear edge populations are ‘marginal’ since they occur at the limit of the species’ ecological tolerance and are expected to decline in performance as climate warming pushes them to extirpation. However, conflicts between observations and predictions are increasingly accumulating and little progress has been made in explaining this disparity. We argue that a revision of the concept of marginality is necessary, together with explicit testing of population decline, which is increasingly possible as data availability improves. Such action should be based on taking the population perspective across a species’ rear edge, encompassing the ecological, geographical and genetic dimensions of marginality. Refining our understanding of rear edge populations is essential to advance our ability to monitor, predict and plan for the impacts of environmental change on species range dynamics

    The benefits of mountain woodland restoration

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    Mountain woodland ecotones require urgent action to reverse long-term habitat degradation and biodiversity loss. There is growing interest in restoring high-elevation woodland and scrub communities, harnessing planting and natural regeneration. Emissions offsetting has been a key driver, yet mountain systems offer slower mechanisms for biomass accumulation due to their typically smaller size, lower density and slower growth than forests at lower elevations. We argue that the natural capital afforded by mountain woodland restoration is far more comprehensive than carbon sequestration alone and encompasses an important array of ecosystem services and biodiversity gains. Improved opportunities for wildlife and people include natural hazard protection, sheltering, structural variability, vegetation diversity and recreation. Furthermore, mountain woodland restoration provides critically needed nature- based solutions for reducing threats from escalating climate change such as soil erosion, flooding, warming temperatures and extreme weather. It is imperative that these benefits are embedded within conservation policy and environmental incentives.Output Status: Forthcoming/Available Onlin

    InDesignの活用について : InDesignとWordの優位性を踏まえて

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    企業や官公庁で文書を作成するとき,その手段としてWordがよく使われている。このことは,Wordにより文書の品質が制限されているともいえる。しかし,企業や官公庁が広く情報発信をするとき,その品質を高める必要性が出てくる。このとき,ページレイアウトソフトであるInDesign利用することも考えられる。そこで,本稿では,WordとInDesignの文書を作成する能力を評価した上で,両者の機能を比較し,それぞれの機能の優位性を検証することにしたいと思う。このことにより,高みを目指した文書を作成するための何らかの示唆を与えることができればと思う

    Extinction debt on reservoir land-bridge islands

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    Large dams cause extensive inundation of habitats, with remaining terrestrial habitat confined to highly fragmented archipelagos of land-bridge islands comprised of former hilltops. Isolation of biological communities on reservoir islands induces local extinctions and degradation of remnant communities. “Good practice” dam development guidelines propose using reservoir islands for species conservation, mitigating some of the detrimental impacts associated with flooding terrestrial habitats. The degree of species retention on islands in the long-term, and hence, whether they are effective for conservation is currently unknown. Here, we quantitatively review species' responses to isolation on reservoir islands. We specifically investigate island species richness in comparison with neighbouring continuous habitat, and relationships between island species richness and island area, isolation time, and distance to mainland and to other islands. Species' responses to isolation on reservoir islands have been investigated in only 15 of the > 58,000 large-dam reservoirs (dam height > 15m) operating globally. Research predominantly originates from wet tropical forest habitats and focuses on mammals, with species richness being the most widely-reported ecological metric. Terrestrial taxa are, overall, negatively impacted by isolation on reservoir islands. Reservoir island species richness declines with isolation time, and although the rate of loss is slower on larger islands, all islands exhibit depauperate species richness < 100 years after isolation, compared to continuous mainland habitats. Such a pattern of sustained and delayed species loss following large-scale habitat disturbance is indicative of an extinction debt existing for reservoir island species: this pattern is evident across all taxonomic groups and dams studied. Thus, reservoir islands cannot reliably be used for species conservation as part of impact mitigation measures, and should instead be included in area calculations for land impacted by dam creation. Environmental licensing assessments as a precondition for future dam development should explicitly consider the long-term fate of island communities when assessing biodiversity loss vs energy output

    ¿Cómo influye la riqueza genética de los abetos pirenaicos en su respuesta al cambio climático?

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    Noticia publicada por la Agencia Sinc: El Servicio de Información y Noticias Científicas (SINC) es la primera agencia pública de ámbito estatal especializada en información sobre ciencia, tecnología e innovación en español. En la página web de iAguaUn estudio demuestra que los abetares más antiguos son más tolerantes a condiciones de aumento de temperatura y disminución de precipitación. El mantenimiento de la diversidad ayuda a los expertos a contar con individuos adaptados, idóneos en las restauraciones, que eviten el decaimiento de la especie.N

    Genes y edad de los abetos pirenaicos, claves en su respuesta al cambio climático

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    Noticial en el Blog de la Web Fundación Descubre: Fundación Andaluza para la Divulgación de la Innovación y el ConocimientoUn estudio demuestra que los abetares más antiguos son más tolerantes a condiciones de aumento de temperatura y disminución de precipitación. El mantenimiento de la diversidad ayuda a los expertos a contar con individuos adaptados, idóneos en las restauraciones, que eviten el decaimiento de la especie.Peer reviewe

    Isolation of polymorphic microsatellites in the stemless thistle (Cirsium acaule) and their utility in other Cirsium species

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    The genus Cirsium includes species with both widespread and restricted geographical distributions, several of which are serious weeds. Nine polymorphic microsatellite loci were isolated from the stemless thistle Cirsium acaule. Eight were polymorphic in C. acaule, six in C. arvense and seven in C. heterophyllum. One locus monomorphic in C. acaule showed polymorphism in C. heterophyllum. The mean number of alleles per locus was 4.1 in C. acaule, 6.2 in C. arvense and 2.9 in C. heterophyllum. These nine loci were also amplified in C. eriophorum and C. vulgare, suggesting that these markers may be of use throughout the genus

    Onward but not always upward: individualistic elevational shifts of tree species in subtropical montane forests

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    Ongoing global climate change is driving widespread shifts in species distributions. Trends show frequent upwards shifts of treelines, but information on changes in montane forest below the treeline and in the tropics and sub-tropics is limited, despite the importance of these areas for biodiversity and ecosystem function. Patterns of species shifts in tropical and subtropical regions are likely to be more complex and individualistic than global averages suggest due to high species diversity and strong influence of competition, alongside direct climatic limitations on distributions. To address the question of how subtropical montane tree species are likely to move as climate changes, we used an extensive national forest inventory to estimate distribution shifts of 75 tree species in Taiwan by comparing the optimum elevation and range edges of adults and juveniles within species. Overall there was a significant difference in optimum elevation of adults and juveniles. Life stage mismatches suggested upward shifts in 35% of species but downward shifts of over half (56%), while 8% appeared stable. Upward elevation shifts were disproportionately common in high elevation species, whilst mid to low elevation species suggested greater variation in shift direction. Whilst previous research on mountain forest range shifts has been dominated by work addressing changes in treeline position, we show that although high elevation species shift up, below the treeline species may shift individualistically, heralding widespread changes in forest communities over coming decades. The wide variation of responses indicated is likely driven by individual species responses to interacting environmental factors such as competition, topography and anthropogenic influences across the broad range of forest types investigated. As global environmental changes continue, more detailed understanding of tree range shifts across a wide spectrum of forests will allow us to prepare for the implications of such changes for biodiversity, ecosystem function and dependent human populations

    Structural overshoot of tree growth with climate variability and the global spectrum of drought-induced forest dieback

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    Ongoing climate change poses significant threats to plant function and distribution. Increased temperatures and altered precipitation regimes amplify drought frequency and intensity, elevating plant stress and mortality. Large-scale forest mortality events will have far-reaching impacts on carbon and hydrological cycling, biodiversity, and ecosystem services. However, biogeographical theory and global vegetation models poorly represent recent forest die-off patterns. Furthermore, since trees are sessile and long-lived, their responses to climate extremes are substantially dependent on historical factors. We show that periods of favourable climatic and management conditions that facilitate abundant tree growth can lead to structural overshoot of above-ground tree biomass due to a subsequent temporal mismatch between water demand and availability. When environmental favourability declines, increases in water and temperature stress that are protracted, rapid, or both, drive a gradient of tree structural responses that can modify forest self-thinning relationships. Responses ranging from premature leaf senescence and partial canopy dieback to whole-tree mortality reduce canopy leaf area during the stress period, and for a lagged recovery window thereafter. Such temporal mismatches of water requirements from availability can occur at local to regional scales throughout a species geographical range. Since climate change projections predict large future fluctuations in both wet and dry conditions, we expect forests to become increasingly structurally mismatched to water availability and thus over-built during more stressful episodes. By accounting for the historical context of biomass development, our approach can explain previously problematic aspects of large-scale forest mortality, such as why it can occur throughout the range of a species and yet still be locally highly variable, and why some events seem readily attributable to an ongoing drought while others do not. This refined understanding can facilitate better projections of structural overshoot responses, enabling improved prediction of changes to forest distribution and function from regional to global scales
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