1,720,954 research outputs found
The Effects of Ecological Restoration on Nitrogen Partitioning in Wetland Ecosystems
No full textNitrogen (N) is essential for plant growth, but excessive inputs from fertilisers, livestock waste, and non-native N-fixing plants can overwhelm ecosystems. Wetlands, often referred to as “nature’s kidneys”, play a key role in buffering excess N. However, despite their importance, over 90% of New Zealand’s wetlands have been lost or degraded, and our understanding of how wetland condition influences N pools and fluxes remains limited. Ecological restoration is the process of repairing human-altered ecosystems to resemble their approximate natural structure and function. Research on N dynamics in restored wetlands, particularly those converted from agroecosystems, is sparse. Wetland swamp forests, despite having the highest N retention capacity among wetland types, also remain largely understudied. My thesis aimed to address these knowledge gaps by examining how ecological restoration affects N dynamics (pools and fluxes) across three wetland states: unrestored wetlands (actively disturbed by agriculture), restored wetlands (undergoing active restoration following agriculture), and remnant wetlands (mature swamp forest). I sampled soils, leaves, roots, wood, and bark from 19 wetlands across the Wairarapa region of New Zealand. Samples were analysed for percent N (%N) and δ¹⁵N values, with soils additionally analysed for mineral and microbial N. I hypothesised that (1) plant tissue %N would be highest in remnant wetlands, due to greater plant functional diversity and biomass; (2) soils in unrestored wetlands would have higher total N and mineral N content, but lower microbial N, due to different N source inputs, reduced plant biomass, and lower amounts of soil organic matter storing less N; (3) plant tissue δ¹⁵N values would be lowest in remnant wetlands, followed by restored and unrestored wetlands, mirroring dominant N source inputs; and (4) soil δ¹⁵N values would show the same pattern, with remnant wetlands having the lowest δ¹⁵N values due to greater soil organic matter and microbial diversity, which reduces ¹⁴N loss. I found total ecosystem N ranged from 504 g m⁻² (± 82.2 SE) in unrestored wetlands to 654 g m⁻² (± 156 SE) in restored wetlands and 906 g m⁻² (± 118 SE) in remnant wetlands. However, these differences were not statistically significant due to high variability among wetlands of each state. When total ecosystem N was partitioned, linear models showed remnant wetlands stored significantly more N in above-ground biomass (herb and canopy foliage) than restored and unrestored wetlands. Surprisingly, soil percent N and mineral N (nitrate (NO₃⁻) and ammonium (NH4+)) did not differ significantly among wetland states, but when bulk density of soil was accounted for, the soil mineral fraction NO₃⁻ was greatest in unrestored wetlands. Microbial N differed significantly by wetland state, with remnant wetlands holding more N in microbial biomass than unrestored and restored wetlands. Remnant wetlands had the lowest δ¹⁵N values in soil, coarse roots, fine roots, and canopy foliar N pools. Herb layer δ¹⁵N did not differ between remnant and restored wetlands but was significantly higher in unrestored wetlands. Soil and fine root δ¹⁵N values were similar between unrestored and restored wetlands. Overall, my findings highlight the complex responses of wetland N pools and fluxes to ecosystem state. Restoration increases N uptake and long-term N storage, but restored wetlands still hold less N than remnant wetlands, possibly indicating ongoing capacity for further uptake as restored wetlands mature. These results underscore the critical importance of protecting and restoring wetlands to remove excess N from landscapes, safeguarding freshwater and human health and enhancing landscape resilience.</p
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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