647 research outputs found

    Classification of natural flow regimes in the Ebro basin (Spain) by using a wide range of hydrologic parameters

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    Clasificación de tipos de régimenes naturales de caudales a partir de parámetros de tres componentes del régimen fluvial: magnitud, frecuencia y duración

    Sustaining Healthy Freshwater Ecosystems

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    Friedel–Crafts hydroxyalkylation of indoles mediated by trimethylsilyl trifluoromethanesulfonate

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    Indoles and N-alkylindoles undergo Friedel–Crafts addition to aldehydes in the presence of trimethylsilyl trifluoromethanesulfonate and a trialkylamine to produce 3-(1- silyloxyalkyl)indoles. Neutralization of the reaction mixture with pyridine followed by deprotection under basic conditions with tetrabutylammonium fluoride provides the 1:1 adduct as the free alcohol. This method prevents spontaneous conversion of the desired products to the thermodynamically favored bisindolyl(aryl)methanes, a process typically observed when indoles are reacted with aldehydes under acidic conditions

    Uncovering Shakespeare\u27s Sisters in Special Collections and College Archives, Musselman Library

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    Foreword by Professor Suzanne J. Flynn I have taught the first-year seminar, Shakespeare’s Sisters, several times, and over the years I have brought the seminar’s students to the Folger Shakespeare Library in Washington, D.C. There, the wonderful librarians have treated the students to a special exhibit of early women’s manuscripts and first editions, beginning with letters written by Elizabeth I and proceeding through important works by seventeen and eighteenth-century women authors such as Aemelia Lanyer, Anne Finch, Aphra Behn, and Mary Wollstonecraft. This year I worked with Carolyn Sautter, the Director of Special Collections and College Archives, to give my 2018 seminar students the opportunity to produce a sequel to the Folger exhibit of early modern women writers. Special Collections houses an impressive array of first editions from the nineteenth and twentieth centuries, many of them acquired from Thomas Y. Cooper, the former editor of the Hanover Evening Sun newspaper, who donated over 1600 items to Musselman Library in 1965. Working with Kerri Odess-Harnish, we chose first editions of eight significant works of literature written by American and British women from the mid-nineteenth through the mid-twentieth centuries. The students worked in pairs, researching a single book and producing a report that outlines important biographical facts about the author, the book’s publication and reception history, and finally the significance of the book in the years since its publication. We hope that our project will draw attention to the wealth of literary treasures housed in Special Collections at Musselman Library, but especially to these works by eight of “Shakespeare’s Sisters.

    Validating anthropogenic threat maps as a tool for assessing river ecological integrity in Andean-Amazon basins

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    Anthropogenic threat maps are commonly used as a surrogate for the ecological integrity of rivers in freshwater conservation, but a clearer understanding of their relationships is required to develop proper management plans at large scales. Here, we developed and validated empirical models that link the ecological integrity of rivers to threat maps in a large, heterogeneous and biodiverse Andean-Amazon watershed. Through fieldwork, we recorded data on aquatic invertebrate community composition, habitat quality, and physical-chemical parameters to calculate the ecological integrity of 140 streams/rivers across the basin. Simultaneously, we generated maps that describe the location, extent, and magnitude of impact of nine anthropogenic threats to freshwater systems in the basin. Through seven-fold cross-validation procedure, we found that regression models based on anthropogenic threats alone have limited power for predicting the ecological integrity of rivers. However, the prediction accuracy improved when environmental predictors (slope and elevation) were included, and more so when the predictions were carried out at a coarser scale, such as microbasins. Moreover, anthropogenic threats that amplify the incidence of other pressures (roads, human settlements and oil activities) are the most relevant predictors of ecological integrity. We concluded that threat maps can offer an overall picture of the ecological integrity pattern of the basin, becoming a useful tool for broad-scale conservation planning for freshwater ecosystems. While it is always advisable to have finer scale in situ measurements of ecological integrity, our study shows that threat maps provide fast and cost-effective results, which so often are needed for pressing management and conservation actions

    Trait-based ecology at large scales: Assessing functional trait correlations, phylogenetic constraints and spatial variability using open data

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    The growing use of functional traits in ecological research has brought new insights into biodiversity responses to global environmental change. However, further progress depends on overcoming three major challenges involving (a) statistical correlations between traits, (b) phylogenetic constraints on the combination of traits possessed by any single species, and (c) spatial effects on trait structure and trait–environment relationships. Here, we introduce a new framework for quantifying trait correlations, phylogenetic constraints and spatial variability at large scales by combining openly available species’ trait, occurrence and phylogenetic data with gridded, high‐resolution environmental layers and computational modelling. Our approach is suitable for use among a wide range of taxonomic groups inhabiting terrestrial, marine and freshwater habitats. We demonstrate its application using freshwater macroinvertebrate data from 35 countries in Europe. We identified a subset of available macroinvertebrate traits, corresponding to a life‐history model with axes of resistance, resilience and resource use, as relatively unaffected by correlations and phylogenetic constraints. Trait structure responded more consistently to environmental variation than taxonomic structure, regardless of location. A re‐analysis of existing data on macroinvertebrate communities of European alpine streams supported this conclusion, and demonstrated that occurrence‐based functional diversity indices are highly sensitive to the traits included in their calculation. Overall, our findings suggest that the search for quantitative trait–environment relationships using single traits or simple combinations of multiple traits is unlikely to be productive. Instead, there is a need to embrace the value of conceptual frameworks linking community responses to environmental change via traits which correspond to the axes of life‐history models. Through a novel integration of tools and databases, our flexible framework can address this need

    River Flows and Water Wars: Emerging Science for Environmental Decision Making

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    Real and apparent conflicts between ecosystem and human needs for fresh water are contributing to the emergence of an alternative model for conducting river science around the world. The core of this new paradigm emphasizes the need to forge new partnerships between scientists and other stakeholders where shared ecological goals and river visions are developed, and the need for new experimental approaches to advance scientific understanding at the scales relevant to whole-river management. We identify four key elements required to make this model succeed: existing and planned water projects represent opportunities to conduct ecosystem-scale experiments through controlled river flow manipulations; more cooperative interactions among scientists, managers, and other stakeholders are critical; experimental results must be synthesized across studies to allow broader generalization; and new, innovative funding partnerships are needed to engage scientists and to broadly involve the government, the private sector, and NGOs
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