1,720,977 research outputs found
Mapping soil organic matter in the Baranja region (Croatia) : Geological and anthropic forcing parameters
No full textSpatial mapping of soil organic matter (SOM) and evaluation of the related natural and anthropic influencing factors are crucial to monitor the extent of degraded land and the evolution of soil functions. The objective of this work is to study the spatial distribution of SOM in a highly exploited agricultural area in the Baranja Region (Croatia). The spatially dense dataset available (4825 top-soil samples from 0 to 30 cm) allowed to produce reliable SOM maps using geostatistical interpolation kriging algorithms and to study the relationships with possible influencing factors. The interpolation has been conducted by means of two approaches. In one approach, the overall data set is considered for computing a global variogram and performing a direct interpolation of SOM values. In the second approach, the data are stratified according to two different geological and morphogenetic domains, Holocene Domain (HD) and Pleistocene Domain (PD), and a distinct geostatistical analysis is performed in each domain. The results showed that average SOM in the studied region was 2.29%, indicating a future need for adopting sustainable soil management practices in this region. SOM was significantly higher in HD (2.64%) than PD (1.97%) domain. SOM in PD generally had a much lower global variability. Global dataset analysis reveals that regional intrinsic factors prevail over local intrinsic and extrinsic factors in determining SOM spatial patterns. In contrast, the stratified approach can filter the effect of regional variability related to the main geological and geomorphological setting. The structural spatial correlation in PD is weaker than in HD, as manifested by spatial patches of low and high SOM content with smaller extension in PD with respect to HD. The strong relationships between SOM spatial patterns and geological/geomorphological factors suggest the possibility of adopting finer subdivision criteria in future research
Short-range and regional spatial variability of soil chemical properties in an agro-ecosystem in eastern Croatia
No full textSpatial and temporal characterization of soil properties in agro-ecosystems is crucial for monitoring the evolution of soil functions and for understanding the main influential processes. Moreover, the objective mapping of soil properties in agro-ecosystems is urgently needed for regional planning purposes and the proper choice of land management practices. In this work, the geostatistical analysis of a dataset of soil properties, derived from 2411 soil samples collected in Vukovar-Srijem County (Croatia), highlighted the multiple benefits of a spatial-statistical approach. The main aim of this paper is to jointly examine short-range (i.e., within-field) and regional spatial variability of several soil chemical properties: soil pH, organic matter (OM), plant available phosphorus (AP) and potassium (AK). The available sampling network, characterized by a set of 2411 (0–30 cm depth) irregularly and field-clustered soil samples, allowed to derivate of two typologies of soil nutrient maps by means of ordinary block kriging: within-field high-resolution maps (block size 250 m) and regional low-resolution maps (block size 2000 m). Soil pH and OM had lower variability compared to AP and AK. The OM content and pH ranged from 1.24% to 5.25% and from 3.69 to 7.84, respectively. Almost 94% of all samples had an OM content below 3%, indicating the need for future adoption of environmentally friendly soil management in this county. The mean values of AP and AK were 173 mg kg− 1 and 238 mg kg− 1, respectively, indicating a moderate supply of these nutrients. Geostatistical analysis revealed that the best-fit models were spherical for pH and AP, with moderate spatial dependency, and exponential for OM and AK, with strong spatial dependency. The within-field high-resolution soil property maps can be used as guidance for site-specific fertilization and liming. In addition, the regional maps derived for larger interpolation support provide quantitative information for regional planning and environmental monitoring and protection purposes. Consequently, the multi-resolution mapping of soil properties and the analysis of their spatial variability highlighted possible connections with influential factors and processes, including the relationships with different soil types. Finally, quantification of the spatial variability of soil properties by means of variogram models constitutes a basis for optimizing soil sample spacing for mapping purposes in the studied region
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
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
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