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Der Einfluss reduzierter Bodenbearbeitung auf die Klimaresilienz von landwirtschaftlich genutzten Böden : Untersuchungen zur Aggregatstabilität und mikrobiellen Biomasse
No full textExtremwetterereignisse wie Dürreperioden und Starkregen nehmen aufgrund des Klimawandels zu und stellen die Landwirtschaft vor Herausforderungen. Daher müssen landwirtschaftlich genutzte Böden klimaresilient werden, also u. a. möglichst gut Wasser speichern und gleichzeitig Niederschläge schnell genug infiltrieren, um Bodenerosion infolge von Starkniederschlägen zu vermeiden. Um die Böden zu schützen und dennoch eine nachhaltige Bewirtchaftung dieser zu ermöglichen, rücken reduzierte Bodenbearbeitungssysteme immer mehr in den Fokus. In dieser Arbeit wird daher der Einfluss vier verschiedener Varianten reduzierter Bodenbearbeitung auf die Klimaresilienz von landwirtschaftlich genutzten Böden im Rahmen eines Feldversuches auf einer lößgeprägten Ackerfläche in der Nähe von Ibbenbüren analysiert. Mittels Bodenproben werden eine Direktsaatvariante und drei Mulchsaatvarianten mit 8, 15 bzw. 25 cm Bearbeitungstiefe im Labor auf Aggregatstabilität und den Gehalt mikrobieller Biomasse sowie weitere Begleitparameter untersucht. Die vorangegangene Literaturrecherche zeigt, dass sich unter reduzierter Bodenbearbeitung die Klimaresilienz der untersuchten Standorte, im Sinne von höheren Aggregatstabilitäten, höheren Infiltrationsraten und vermindertem Bodenabtrag im Vergleich zu konventioneller Bearbeitung mit dem Pflug grundsätzlich verbessert. Dabei übertrifft die Direktsaat häufig die konservierende Bodenbearbeitung. Auch auf die mikrobielle Biomasse wirkt sich die reduzierte Bodenbearbeitung positiv aus, was wiederum die Aggregierung positiv beeinflusst und weitere Vorteile für die Stresstoleranz der Kulturpflanzen durch z. B. Symbiosen und funktionierende Nährstoffkreisläufe im Boden mit sich bringt. In dem Bodenbearbeitungsversuch konnten keine signifikanten Unterschiede zwischen den Varianten für die untersuchten Parameter (mit Ausnahme des N-Gesamtgehalts) festgestellt werden. Dennoch wurden insbesondere für die Aggregatstabilität positiv zu bewertende Mittelwerte zwischen 70,0 und 73,9 % ermittelt. Aufgrund des Versuchsdesigns ist jedoch eine finale Aussage über den Einfluss reduzierter Bodenbearbeitung auf die Klimaresilienz dieses Standorts mit diesem Versuch nicht möglich. Die Literatur zeigt, dass letztlich die Kombination aus einer stabilen Bodenstruktur, einem aktiven Bodenleben und ausreichender Bodenbedeckung auf die Klimaresilienz eines landwirtschaftlich genutzten Bodens einspielen. Der Erfolg einer bestimmten Bodenbearbeitungsform hängt dabei aber von weiteren Faktoren wie Standorteigenschaften, insbesondere der Bodenart; Fruchtfolgegestaltung und passender Einstellung der Arbeitsgeräte ab.Climate change is becoming increasingly noticeable with more frequent extreme weather events such as droughts and heavy rainfall. Future cultivation systems must become climate resilient, i.e. soils must store water very well while at the same time allowing water to infiltrate quickly enough to prevent soil erosion caused by heavy rainfall. In order to protect the soil and still enable sustainable cultivation, reduced tillage systems are becoming more important. This thesis therefore examines the influence of four different variants of reduced tillage on the climate resilience of agricultural soils as part of a field trial on a loess-dominated farmland near Ibbenbüren. Using soil samples, a no-till variant and three mulch sowing variants with tillage depths of 8, 15 and 25 cm are analysed in the laboratory for aggregate stability, microbial biomass and other parameters. The literature research shows that the climate resilience of soils, in the sense of higher aggregate stability, infiltration rates and reduced soil erosion compared to conventional tillage, is fundamentally improved under reduced tillage systems. In some cases, no-till performed even better than variants of conservation tillage. Reduced tillage also has a positive effect on microbial biomass which influences aggregation processes and brings further advantages for the stress resistance of the crop plants, e.g. through symbioses and the nutrient cycles in the soil. In the trial for this thesis no significant differences were found between the reduced tillage variants for the analysed parameters (with the exception of the total N content). Nevertheless, positive values between 70.0 and 73.9 % were determined for aggregate stability. However, due to the experimental design, a final statement on the influence of reduced tillage on the climate resilience of this farmland is not possible. Finally, the literature shows that the combination of a stable soil structure, active soil life and soil cover through mulch and/or vegetation is particularly important for the climate resilience of agricultural soils. However, the success of a particular form of tillage also depends on other factors such as soil characteristics, especially the soil texture; crop rotation and the correct configuration of the equipment
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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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