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Unravelling urban soil properties and their spatial patterns to assess urban soil functioning
No full textBeleidsmakers, stadsplanners en -ontwikkelaars zijn zich steeds bewuster van het belang van bodems in stedelijke gebieden. De benodigde instrumenten om het functioneren van deze bodems zorgvuldig te monitoren en waarderen zijn echter niet voor handen wegens een gebrek aan empirische bodemgegevens en ontoereikende inzichten inzake stedelijke bodemprocessen en -functies, zowel in tijd als ruimte. Dit onderzoek beoogt de (ruimtelijke) verscheidenheid van stadsbodems, hun eigenschappen en functies beter te begrijpen en te voorspellen, om zo de bestaande lacune aan stedelijke bodeminformatie op te vullen. Hoofdstuk 1 onderstreept de noodzaak naar bodemonderzoek in de stedelijke omgeving en presenteert de algemene doelstelling en specifieke onderzoeksvragen van het onderzoek. Hoofdstuk 2 evalueert het gebruik van actuele landbedekkingsgegevens om een inschatting te maken van de lacune aan stedelijke bodeminformatie, waarbij het sterk verstedelijkte Vlaams Gewest in België als gevalstudie wordt gebruikt. Hoofdstuk 3 stelt een verbeterde aanpak van de ‘FAO Richtlijnen voor bodembeschrijving’ voor om bodemhorizonten in door de mens verstoorde bodems, en stadsbodems in het bijzonder, zinvoller aan te duiden. Hoofdstuk 4 vormt de basis voor hoofdstukken 5, 6 en 7 en beschrijft het studiegebied, de selectie van locaties voor staalname, de bemonsteringsmethodologie, alsook de toegepaste methodes voor bodembeschrijving en bodemanalyse voor de fysicochemische karakterisering van 16 stadsbodems uit de stad Gent. Hoofdstuk 5 onderzoekt de potentiële bijdrage van metingen van volume-specifieke magnetische susceptibiliteit, en/of multi-elementanalyses met behulp van röntgenfluorescentie (XRF), voor het onthullen van antropogene, lithogene, en pedologische verschillen in en tussen stadsbodems in de stad Gent. Hoofdstuk 6 bestudeert de fysicochemische eigenschappen van, en bodemvorming in 16 stadbodems in de stad Gent met verschillende moedermaterialen, en evalueert of informatie over landgebruik, tijdsduur sinds verstedelijking en voorstedelijke geomorfologie kan bijdragen tot een beter begrip en betere ruimtelijke voorspelling van stedelijke bodemeigenschappen en moedermaterialen. Hoofdstuk 7 biedt inzicht in het gezamenlijke aanbod van tien bodemfuncties voor een selectie van vijf stadsbodems uit de stad Gent met een gradiënt van toenemende antropogene invloed. In hoofdstuk 8 de belangrijkste bevindingen uit de verschillende hoofdstukken samengevat en met elkaar verbonden en wordt kritisch gereflecteerd over de methoden voor gegevensverzameling. Tot slot worden maatschappelijke bedenkingen en aanbevelingen voor toekomstig onderzoek geformuleerd. De waardevolle inzichten omtrent de diversiteit van stadsbodems, hun eigenschappen en functies, verkregen in dit onderzoek, leveren een bijdrage aan het duurzamer gebruik en beheer van stadsbodems
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
Spatial patterns of heavy metal contamination by urbanization
Get PDFSpatial analysis of heavy metals (HMs) is an important step toward developing predictive models of urban HM contamination. This study assessed the spatial distribution of the enrichment of eight HMs (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) in the city of Ghent, Belgium. A database with soil HM concentrations measured at 2194 point observations was collected from the Public Waste Agency of Flanders. The degree of anthropogenic HM enrichment was quantified using an urban pollution index (PI). Enrichment of HMs showed high variations throughout the study area. Observed concentrations of As, Cd, Cr, and Hg did not exceed expected background values for the majority of the sampling locations (PI 1) in 66, 76, 68, and 66% of the cases. The predicted PI means for the entire study area were 3.46 (Cu), 2.06 (Ni), 3.26 (Pb), and 3.28 (Zn). Comparison between various land use types and times since development indicated that HM enrichment was generally highest in urban land uses built up before 1933. Results, however, suggested that spatial patterns of HM contamination are difficult to predict in cities with a long history of industrialization without knowledge on the spatial distribution of (potentially) contaminating historical industrial activities
Revealing urban soil properties and their spatial patterns to optimize urban soil management
Get PDFToday more than half of the world’s population is living in urbanized areas. Traditionally focusing on agricultural and natural soils, the soil research community only recently acknowledged the critical role of urban soils as provisioner of ecosystem services by means of supporting plant growth, regulating the bioavailability of pollutants, their role in the hydrological cycle, carbon storage, air and water filtration and conserving soil biodiversity. An improved understanding of the role of soils in the urban environment, the spatial patterns of their chemical, biological and physical soil properties and the impacts of urbanization across the urban landscape is essential to the sustainable management of the urban soil resource. A review is given on current state of knowledge on urban soils and soil properties and the impacts of urbanization. Mapping soil properties in urban areas remains a challenge, as spatial heterogeneity is an unambiguous feature of urban soils. Physical disturbance, incorporation of anthropogenic materials, site history as well as land use and cover and their particular management practices all contribute to the mosaic of soil patches observed in the urban landscape. Understanding how these impacts of urbanization influence soil properties should be a key challenge to soil scientists, as lack of knowledge on the current status of our urban soils complicates efforts towards more sustainable urban soil management. We will demonstrate how soil scientists can play a key role in urban planning and management of urban soils, as to safeguard the many critical ecosystem functions they can provide
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