1,720,953 research outputs found
Effect of organic and conventional management on soil invertebrates and vascular plants in vineyards
No full textopenNegli ultimi anni è aumentata notevolmente l’attenzione globale ad un utilizzo più consapevole e sostenibile degli agroecosistemi che supporti la biodiversità e i servizi ecosistemici. Le colture permanenti, come i vigneti, potrebbero mantenere un’elevata biodiversità rispetto alle colture annuali, per via della maggiore stabilità e del minore disturbo. Tuttavia, i vigneti continuano a rappresentare uno degli agroecosistemi più dipendenti dai pesticidi in Europa.
Tra le strategie proposte per mitigare gli impatti della gestione intensiva vi è la conversione all’agricoltura biologica, considerata una pratica promettente per la conservazione della biodiversità e il mantenimento delle funzioni ecosistemiche. Tuttavia, se da un lato l’agricoltura convenzionale si caratterizza per l’uso di fitofarmaci chimici e fertilizzanti di sintesi, dall’altro anche i sistemi biologici possono includere lavorazioni meccaniche del suolo e l’impiego di sostanze non sintetiche che possono anch’esse avere effetti negativi sulla biodiversità.
Questo studio, svolto nell’ottobre 2024 in 14 vigneti situati nel Parco Regionale dei Colli Euganei e nel Parco Naturale dei Colli Berici in Veneto, Italia, ha l’obiettivo di indagare la copertura e diversità di specie erbacee e l’abbondanza di diversi taxa di invertebrati tra i sistemi convenzionali e biologici. Una prima analisi riguarda la vegetazione spontanea tra i filari e interfilari dei vigneti biologici e convenzionali. Di queste è stata indagata l’altezza e la copertura percentuale del suolo, oltre ad un’indagine sulla ricchezza di specie. I nostri risultati hanno evidenziato una altezza e copertura vegetazionale maggiore in vigneti biologici, con altezza media di 24.5 cm e copertura di 92.2%. Per i vigneti a gestione convenzionale la percentuale di suolo nudo non coperto vegetativamente, in media il 20.3%, è notevolmente superiore. Una seconda analisi si focalizza invece sulla comunità di invertebrati del suolo, in particolare: Carabidae, Staphylinidae, Formicidae, Diplopoda, Chilopoda, Arachnida, Collembola, Isopoda, Dermaptera, Helicidae, Limacidae, Lumbricidae. Gli esemplari sono stati prelevati tramite trappole a caduta e ne è stata valutata l’abbondanza media in ogni trappola collocata in vigneti biologici e convenzionali. I risultati mostrano differenze significative per la classe Diplopoda e l’ordine Isopoda, con un’abbondanza maggiore in vigneti biologici. È stata riscontrata inoltre una tendenza ad una maggior presenza di stafilinidi nel biologico.
In definitiva, i risultati di questo studio mostrano che la gestione biologica può avere un effetto positivo sulla copertura vegetazionale del vigneto e su alcuni gruppi di invertebrati detritivori e predatori. Al contrario, molti gruppi di invertebrati esaminati non sono risultati essere influenzati dalle pratiche di gestione. Questi risultati concordano con una ampia letteratura sulla gestione in vigneto che riscontra effetti spesso contrastanti, molto variabili e taxon-specifici. Tuttavia, per validare e approfondire i risultati di questo studio, sarebbe necessario replicare i campionamenti in primavera/estate e analizzare la diversità di specie nelle due tipologie di vigneto.In recent years, there has been a significant increase in global attention to a more conscious and sustainable use of agroecosystems that supports biodiversity and ecosystem services. Permanent crops, such as vineyards, could maintain a high level of biodiversity compared to annual crops, due to their greater stability and less disturbance. However, vineyards continue to represent one of the most pesticide-dependent agroecosystems in Europe.
Among the strategies proposed to mitigate the impacts of intensive management is the conversion to organic farming, considered a promising practice for the conservation of biodiversity and the maintenance of ecosystem functions. However, while conventional agriculture is characterized by the use of chemical pesticides and synthetic fertilizers, organic systems can also include mechanical soil processing and the use of non-synthetic substances that can also have negative effects on biodiversity.
This study, carried out in October 2024 in 14 vineyards located in the Euganean Hills Regional Park and the Berici Hills Natural Park in Veneto, Italy, aims to investigate the coverage and diversity of herbaceous species and the abundance of different invertebrate taxa between conventional and organic systems. A first analysis concerns the spontaneous vegetation between and between the rows of organic and conventional vineyards. Of these, the height and percentage cover of the soil were investigated, in addition to a survey on the richness of species. Our results highlighted a greater height and vegetation cover in organic vineyards, with an average height of 24.5 cm and coverage of 92.2%. For conventionally managed vineyards the percentage of bare soil not covered by vegetation, on average 20.3%, is significantly higher. A second analysis focuses instead on the soil invertebrate community, in particular: Carabidae, Staphylinidae, Formicidae, Diplopoda, Chilopoda, Arachnida, Collembola, Isopoda, Dermaptera, Helicidae, Limacidae, Lumbricidae. The specimens were collected using pitfall traps and their average abundance was evaluated in each trap placed in organic and conventional vineyards. The results show significant differences for the class Diplopoda and the order Isopoda, with a higher abundance in organic vineyards. A tendency towards a higher presence of staphylinids in organic was also found.
Ultimately, the results of this study show that organic management can have a positive effect on the vegetation cover of the vineyard and on some groups of detritivorous and predatory invertebrates. On the contrary, many groups of invertebrates examined were not affected by management practices. These results are consistent with a large literature on vineyard management that finds often contrasting, highly variable and taxon-specific effects. However, to validate and deepen the results of this study, it would be necessary to replicate the samplings in spring/summer and analyze the species diversity in the two types of vineyards
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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