745 research outputs found

    Pattern scaling using ClimGen: monthly-resolution future climate scenarios including changes in the variability of precipitation

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    Development, testing and example applications of the pattern-scaling approach for generating future climate change projections are reported here, with a focus on a particular software application called “ClimGen”. A number of innovations have been implemented, including using exponential and logistic functions of global-mean temperature to represent changes in local precipitation and cloud cover, and interpolation from climate model grids to a finer grid while taking into account land-sea contrasts in the climate change patterns. Of particular significance is a new approach for incorporating changes in the inter-annual variability of monthly precipitation simulated by climate models. This is achieved by diagnosing simulated changes in the shape of the gamma distribution of monthly precipitation totals, applying the pattern-scaling approach to estimate changes in the shape parameter under a future scenario, and then perturbing sequences of observed precipitation anomalies so that their distribution changes according to the projected change in the shape parameter. The approach cannot represent changes to the structure of climate timeseries (e.g. changed autocorrelation or teleconnection patterns) were they to occur, but is shown here to be more successful at representing changes in low precipitation extremes than previous pattern-scaling methods

    Markedly Divergent Tree Assemblage Responses to Tropical Forest Loss and Fragmentation across a Strong Seasonality Gradient

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    We examine the effects of forest fragmentation on the structure and composition of tree assemblages within three seasonal and aseasonal forest types of southern Brazil, including evergreen, Araucaria, and deciduous forests. We sampled three southernmost Atlantic Forest landscapes, including the largest continuous forest protected areas within each forest type. Tree assemblages in each forest type were sampled within 10 plots of 0.1 ha in both continuous forests and 10 adjacent forest fragments. All trees within each plot were assigned to trait categories describing their regeneration strategy, vertical stratification, seed-dispersal mode, seed size, and wood density. We detected differences among both forest types and landscape contexts in terms of overall tree species richness, and the density and species richness of different functional groups in terms of regeneration strategy, seed dispersal mode and woody density. Overall, evergreen forest fragments exhibited the largest deviations from continuous forest plots in assemblage structure. Evergreen, Araucaria and deciduous forests diverge in the functional composition of tree floras, particularly in relation to regeneration strategy and stress tolerance. By supporting a more diversified light-demanding and stress-tolerant flora with reduced richness and abundance of shade-tolerant, old-growth species, both deciduous and Araucaria forest tree assemblages are more intrinsically resilient to contemporary human-disturbances, including fragmentation-induced edge effects, in terms of species erosion and functional shifts. We suggest that these intrinsic differences in the direction and magnitude of responses to changes in landscape structure between forest types should guide a wide range of conservation strategies in restoring fragmented tropical forest landscapes worldwide

    Difficulties related to work in the certification process for organic production

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    This study discusses issues related to work in the certification process of Organic Production Units (OPU). Data was collected from ten producers in the region of Campinas, Sao Paulo Brazil, which represent the majority of producers of certified organic vegetables and fruits. The methodology used was an adaptation of Ergonomic Work Analysis method, and structured interviews. As OPU are small and most people perform many tasks related to the various work systems, there is little specialization. Their activities are uncomfortable, awkward physical postures and significant efforts are necessary to perform the work in horticulture. Tasks are predominantly manual and just a few of them can count on the help of mechanization. The certification process and it's maintenance have several implications for farmers, on top of the paperwork, there is an universe of work already so full of activities demanded by the production and marketing systems. The complex context of production, mainly because of its diversity, associated with lack of financial resources and technology, demands from organic farmers to build multiple strategies for business survival. Certification can, contrary to what is expected represent another barrier to the expansion of organic production.4116162616

    The 1983 drought in the West Sahel: a case study

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    Some drought years over sub-Saharan west Africa (1972, 1977, 1984) have been previously related to a cross-equatorial Atlantic gradient pattern with anomalously warm sea surface temperatures (SSTs) south of 10°N and anomalously cold SSTs north of 10°N. This SST dipole-like pattern was not characteristic of 1983, the third driest summer of the twentieth century in the Sahel. This study presents evidence that the dry conditions that persisted over the west Sahel in 1983 were mainly forced by high Indian Ocean SSTs that were probably remanent from the strong 1982/1983 El Niño event. The synchronous Pacific impact of the 1982/1983 El Niño event on west African rainfall was however, quite weak. Prior studies have mainly suggested that the Indian Ocean SSTs impact the decadal-scale rainfall variability over the west Sahel. This study demonstrates that the Indian Ocean also significantly affects inter-annual rainfall variability over the west Sahel and that it was the main forcing for the drought over the west Sahel in 1983

    ENTDECKUNG : Sichtbarmachung einer Symbiose - Natur + Beton: Katalog zur Ausstellung: Exhibition Catalog

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    Der Alleskönner Beton ist grundsätzlich einfach, schnell und kostengünstig in der Herstellung. Er kann nahezu jede beliebige Form annehmen und wird als einziger Baustoff auch flächendeckend in Entwicklungs- und Schwellenländern eingesetzt. Beton hat aber auch seine Schattenseiten. Die Zementherstellung geht mit einem enormen CO2-Ausstoß einher. Zudem wird eine große Menge natürlicher Ressourcen, teils unnötig, verbraucht. Dennoch werden wir auch in Zukunft nicht ohne Beton auskommen, aber wir haben es in der Hand, den Betonbau nachhaltig zu verbessern. Der SFB/Transregio 280 hat zum Ziel, innovative Konzepte und Strategien für ein intelligentes Bauen mit Carbonbeton zu entwickeln. Damit dies gelingt, sind neue Denkweisen, die Änderung bewährter Denkmuster und das Zunutzemachen verschiedenster Inspirationsquellen unabdingbar. Aus diesem Grund hat der SFB/TRR 280 Kunstschaffende dazu eingeladen, sich von den Themen des Sonderforschungsbereiches inspirieren zu lassen. Ziel des Wettbewerbs war es darzustellen, dass Carbonbeton als Produkt von Wissenschaft und Technik vielfältige Beziehungen zu Kunst und Natur aufweist. Was wird sichtbar? Was bleibt dem Forschenden und was dem Außenstehenden verborgen? Wie lassen sich Natur und Carbonbeton als Kunstobjekt verbinden? Im vorliegenden Band wurden alle Einreichungen und das Making-off der prämierten Ideen zusammengestellt.:Wettbewerb - Entdeckung - Ziel 4 Ausschreibung - Ausstellung - Organisation 5 Die Jury 6 1. Platz - Leporello : Suggestion von Bewegung in statischer Präsenz 9 2. Platz - Fibonaccibikini : Hyperbolische Geometrien im Raum 13 3. Platz - Hülle : Ein poetisches Umschreiben der Leere 17 Register: 25 Graukarten 20 Flügel 22 Körperbau : Videokunst / Videoperformance 24 Asymmetrische Ausblicke : Ruhige Ausschnitte versus dynamische Form 26 Trashtopia : Eine Animation 28 Great Barriere Reef 2023 30 Terra : Zerstörung und Erneuerung 32 Nobjects . Eine Serie 34 Luftstütze : Pflanzeninspiriert 36 Die Natur im Inneren : Skulptur aus Carbonbeton 38 Aus dem Boden am Fluss 40 Chaperon 42 Supernatural - Polar 44 Botanik brut : Fotografischer Beton 46 Würfelzwilling 48 Betonkoeppe 50 Voyager 52 Forme perdu 54 Beton durchwachsen : Ein Kustobjekt aus Beton, das der Natur Raum gibt 56 Bonboo 58 QY03 60The all-rounder concrete is basically simple, fast and inexpensive to produce. Concrete components can assume and conserve almost any shape. It is the only building material used extensively also in developing and emerging countries. However, concrete also has its downsides. Cement production is associated with enormous CO2 emissions. In addition, a large amount of natural resources is consumed, sometimes unnecessarily. Nevertheless, we will not be able to build without concrete in the future, but we have it in our hands to improve concrete construction sustainably. The Collaborative Research Centre/Transregio 280 (in short: CRC/TRR 280) aims to develop innovative concepts and strategies for intelligent construction with carbon-reinforced concrete. For this to succeed, new ways of thinking, changing proven patterns of thought and tapping into a wide variety of sources of inspiration are essential. For this reason, we invited artists to be inspired by the research topics of CRC/TRR 280. The aim of the competition was to show that carbon-reinforced concrete, as a product of science and technology, has diverse relationships with art and nature. What becomes visible? What remains hidden to the researcher and what to the outsider? How can nature and carbon-reinforced concrete be combined as art objects? In this catalog, all submissions and the making of the award-winning ideas have been compiled.:Wettbewerb - Entdeckung - Ziel 4 Ausschreibung - Ausstellung - Organisation 5 Die Jury 6 1. Platz - Leporello : Suggestion von Bewegung in statischer Präsenz 9 2. Platz - Fibonaccibikini : Hyperbolische Geometrien im Raum 13 3. Platz - Hülle : Ein poetisches Umschreiben der Leere 17 Register: 25 Graukarten 20 Flügel 22 Körperbau : Videokunst / Videoperformance 24 Asymmetrische Ausblicke : Ruhige Ausschnitte versus dynamische Form 26 Trashtopia : Eine Animation 28 Great Barriere Reef 2023 30 Terra : Zerstörung und Erneuerung 32 Nobjects . Eine Serie 34 Luftstütze : Pflanzeninspiriert 36 Die Natur im Inneren : Skulptur aus Carbonbeton 38 Aus dem Boden am Fluss 40 Chaperon 42 Supernatural - Polar 44 Botanik brut : Fotografischer Beton 46 Würfelzwilling 48 Betonkoeppe 50 Voyager 52 Forme perdu 54 Beton durchwachsen : Ein Kustobjekt aus Beton, das der Natur Raum gibt 56 Bonboo 58 QY03 6

    Forest landscape ecology and global change: an introduction

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    Forest landscape ecology examines broad-scale patterns and processes and their interactions in forested systems and informs the management of these ecosystems. Beyond being among the richest and the most complex terrestrial systems, forest landscapes serve society by providing an array of products and services and, if managed properly, can do so sustainably. In this chapter, we provide an overview of the field of forest landscape ecology, including major historical and present topics of research, approaches, scales, and applications, particularly those concerning edges, fragmentation, connectivity, disturbance, and biodiversity. In addition, we discuss causes of change in forest landscapes, particularly land-use and management changes, and the expected structural and functional consequences that may result from these drivers. This chapter is intended to set the context and provide an overview for the remainder of the book and poses a broad set of questions related to forest landscape ecology and global change that need answers
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