1,720,977 research outputs found
Seasonality of Earthworm Macropores in a Temperate Alpine Area
No full textAbstract: From 9 March 2016 to 12 November 2018 we conducted an intensive experimental field campaign, the WormEx I Experiment, to quantitatively assess the seasonality of the earthworm macropores and their effect on the soil hydrological properties in a temperate mountain range. Six 1-m2 plots were selected in two shallow soils in Valle Camonica (Central Italian Alps) at an elevation of 274 and 935 m a.s.l., in order to count the earthworm macropores. Two plots were amended with calcium trioxocarbonate to stimulate the digging activity. In this work we present results regarding the seasonality of earthworm macropores, its correlation with the antecedent meteorological conditions and the effectiveness of calcium trioxocarbonate. Earthworm activity showed a marked seasonality with Winter hibernation and medium or great digging activity during all the other seasons. A relevant peak of Summer and Autumn macropores was detected in the site at 935 m a.s.l. The castings number resulted very well positively correlated to the antecedent air temperature in both sites. It resulted correlated to the antecedent precipitation, with increasing Pearson’s coefficient at increasing time window in the range from 1 day to 8 weeks. Also, it resulted very well positively correlated to the antecedent average soil water content in a range from 1 to 4 days. Finally, the calcium trioxocarbonate proved to be effective at stimulating the earthworm digging activity
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
Potenzialità e sviluppi del modello di Benfratello e dell'indice di Melisenda per stimare l'evoluzione del bilancio idrologico in ambiente mediterraneo
No full textLand cover changes since the 19th century detected from historic maps for environmental applications: toward a “CORINE 1800” project?
No full textThe value of cartographic heritage for environmental applications is demonstrat-ed with a test case in the Central Italian Alps. Land cover changes since the early 19th century are detected from sample maps of the Second Military Survey of the Habsburg Empire in Lombardy (1818-1829), available on the portal www.mapire.eu. They are compared with 1954 areal surveys and successive land cover classification until 2018. Issues as land use classes homogenization, data vectorization, georeferencing errors are addressed. The dynamics of main land cover classes (woods, bush, meadows, crops) are investigated on sample areas and the potential use of this exercise for hydrological applications is explored. In fact, the impact of the observed natural afforestation on changes in hydrological losses due to evapotranspiration and its influence as a likely cause for the decrease in runoff monitored since 1845 in the Adda river basin and needs to be assessed in a systematic way. The proposed test case can pave the road for a project extended at European scale, a sort of “CORINE 1800 land cover” Geographic Information System, which could have several environmental, cartographic and socio-economic applications
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