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Economic viability of phytoremediation of a cadmium contaminated agricultural area using energy maize: part I: effect on the farmer's income
Get PDFThis paper deals with the economic viability of using energy maize as a phytoremediation crop in a vast agricultural area moderately contaminated with metals. The acceptance of phytoremediation as a remediation technology is, besides the extraction rate, determined by its profitability, being the effects it has on the income of the farmer whose land is contaminated. This income can be supported by producing renewable energy through anaerobic digestion of energy maize, a crop that takes up only relatively low amounts of metals, but that can be valorised as a feedstock for energy production. The effect on the income per hectare of growing energy maize instead of fodder maize seems positive, given the most likely values of variables and while keeping the basic income stable, originating from dairy cattle farming activities. We propose growing energy maize aiming at risk-reduction, and generating an alternative income for farmers, yet in the long run also generating a gradual reduction of the pollution levels. In this way, remediation is demoted to a secondary objective with sustainable risk-based land use as primary objective
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
Magnetic monitoring of particulate matter through different environmental receptors
No full textAbstract: The negative impact of particulate matter (PM) on the living environment is undeniable. Various managerial bodies are striving to reduce PM concentrations in the atmosphere and in this respect, reliable monitoring of PM is crucial. Now that it has become clear that different PM components can give rise to different negative effects, more and more voices are calling for the source-specific composition of PM to be monitored, rather than total PM concentrations. Magnetic methods address this new approach by targeting sectors that emit magnetic PM (MPM), such as the metallurgical industry, mainly after heating or combustion of ferrous components. These methods also allow for fast and non-expensive mapping of MPM impacts at high resolution. In practice, materials (receptors) subject to MPM deposition, such as soil and plants, show enhanced magnetic properties, serving as proxy variables for the spatial impact of MPM. The potential of magnetic monitoring has already been demonstrated in homogeneous areas, but its application within the highly fragmented region of Flanders (Belgium) is as yet unknown. Some practical hurdles have to be overcome, and the potential of time-dependent monitoring, where receptors are exposed to MPM during different periods of time, has not yet been fully clarified. This dissertation examines whether and how ambient magnetic measurements can contribute to source-specific PM monitoring. In a 81-km\ub2 study area between the ports of Ghent and Antwerp (Belgium), marked by strong MPM deposition of a steel and thermal power plant, the existing good practice for magnetic soil measurements is supplemented with guidelines on suitable survey temperatures, local sampling density and depth soundings in heterogeneous areas. It is recommended not to measure at freezing temperatures and to determine local sampling densities a priori based on the local microvariability in the soil. More measurements should be done where microvariability is high. The distribution of MPM through the soil profile furthermore appears to be strongly influenced by variable land use in heterogeneous areas (forests, arable land and pasture). The spatial impact of MPM deposition is therefore more accurately revealed by integrating magnetic measurements through depth. In addition, as the thermal power plant has shut down in 2010, it is shown how temporary MPM receptors (e.g. grass leaves and plastic coated cardboards; PCCs) can discriminate current MPM deposition patterns from historical patterns revealed by soil magnetic records. Finally, magnetic, morphological and chemical analyses of MPM from the steel plant showed that the proposed magnetic methods alone do not allow for discrimination between different MPM sources. However, the methods do facilitate the shift from concentration- to composition-dependent PM monitoring by revealing total MPM impacts. The economic feasibility of setting up a magnetic network remains unclear, but this research shows that the proposed magnetic approach is suited to map local impacts of MPM pollution through time or detect the effect of mitigation measures
Geochemical fingerprinting and magnetic susceptibility to unravel the heterogeneous composition of urban soils
No full textThe typically high heterogeneity of urban soil properties challenges their characterization and interpretation. The ob-jective of this study was to investigate if proximally sensed volume-specific magnetic susceptibility and/or geochemical soil properties can uncover differences in anthropogenic, lithogenic and pedological contributions in, and between, urban soils. We also tested if volume-specific magnetic susceptibility can predict heavy metal enrichment. Data on 29 soil properties of 103 soil horizons from 16 soils from Ghent, Belgium, were analyzed by factor analysis. A correlation analysis, and in-depth analysis of five contrasting urban soils supplemented insights gained from the factor analysis.
The factor analysis extracted four factors: 29.2% of the soil property variability was attributed to fossil fuel combustion and industrial processes, with high (>0.80) loadings for S, organic carbon, magnetic susceptibility, and Zn. Further-more, 26.0 % of the variability was linked to parent material differences, with high loadings (>0.80) for K, Rb and Ti. In absence of geogenic carbonates, increased soil alkalinity due to anthropogenic input of CaCO3 explained 17.0 % of the variability. Lastly, 4.7 % of the variability resulted from variable Zr contents by local geology. Elemental anal-ysis by XRF, possibly combined with magnetic susceptibility measurements, helped to explain lateral or vertical differences related to (1) the nature of anthropogenic influence, for instance burning (e.g., by the S and Zn content) or the incorporation of building rubble (e.g., by the Ca content); (2) the particle size distribution (e.g., by the K, Rb or Ti content); (3) lithology (e.g., by the Zr content); or (4) pedology, such as organic matter build-up (e.g., by the S content) or leaching of alkalis (e.g., by the Ca content). Even though artifacts and soil translocation were common in the studied soils, volume-specific soil magnetic susceptibility measured on fine earth predicted the total heavy metal pollution loading index well (Pearson correlation = 0.85)
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
Energiegewassen op landbouwgronden aangerijkt met zware metalen: onderzoek naar functionaliteitsherstel door middel van fytoextractie en/of biomassateelt als volwaardig alternatief voor klassieke landbouw
No full textnot availabl
Sustainable management of metal contaminated soils in the Campine region using phytoremediation with short rotation coppice
No full textAppropriate 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
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