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Assessment of soil biological quality index (QBS-ar) in different crop rotation systems in paddy soils.
No full textNew methods, based on soil microarthropods for soil quality evaluation have been proposed by some Authors.
Soil microarthropods demonstrated to respond sensitively to land management practices and to be correlated with
beneficial soil functions. QBS Index (QBS-ar) is calculated on the basis of microarthropod groups present in a
soil sample. Each biological form found in the sample receives a score from 1 to 20 (eco-morphological index,
EMI), according to its adaptation to soil environment. The objective of this study was to evaluate the effect of
various rotation systems and sampling periods on soil biological quality index, in paddy soils. For the purpose
of this study surface soil samples (0-15 cm depth) were collected from different rotation systems (rice-rice-rice,
soya-rice-rice, fallow-rice and pea-soya-rice) with three replications, and four sampling times in April (after field
preparation), June (after seedling), August (after tillering stage) and October (after rice harvesting). The study
area is located in paddy soils of Verona area, Northern Italy. Soil microarthropods from a total of 48 samples
were extracted and classified according to the Biological Quality of Soil Index (QBS-ar) method. In addition soil
moisture, Cumulative Soil Respiration and pH were measured in each site. More diversity of microarthropod
groups was found in June and August sampling times. T-test results between different rotations did not show
significant differences while the mean difference between rotation and different sampling times is statistically
different. The highest QBS-ar value was found in the fallow-rice rotation in the forth soil sampling time. Similar
value was found in soya-rice-rice rotation. Result of linear regression analysis indicated that there is significant
correlation between QBS-ar values and Cumulative Soil Respiration
Evaluation of soil quality indicators in paddy soils under different crop rotation systems
No full textSoil quality, by definition, reflects the capacity to sustain plant and animal productivity, maintain or enhance
water and air quality, and promote plant and animal health. Soil quality assessment is an essential issue in
soil management for agriculture and natural resource protection. This study was conducted to detect the effects of
four crop rotation systems (rice-rice-rice, soya-rice-rice, fallow-rice and pea-soya-rice) on soil quality indicators
(soil moisture, porosity, bulk density, water-filled pore space, pH, extractable P, CEC, OC, OM, microbial
respiration, active carbon) in paddy soils of Verona area, Northern Italy. Four adjacent plots which managed
almost similarly, over five years were selected. Surface soil samples were collected from each four rotation
systems in four times, during growing season. Each soil sample was a composite of sub-samples taken from 3
points within 350 m2 of agricultural land. A total of 48 samples were air-dried and passed through 2mm sieve,
for some chemical, biological, and physical measurements. Statistical analysis was done using SPSS. Statistical
results revealed that frequency distribution of most data was normal. The lowest CV% was related to pH. Analysis
of variance (ANOVA) and comparison test showed that there are significant differences in soil quality indicators
among crop rotation systems and sampling times. Results of multivariable regression analysis revealed that soil
respiration had positively correlation coefficient with soil organic matter, soil moisture and cation exchange
capacity. Overall results indicated that the rice rotation with legumes such as bean and soybean improved soil
quality over a long time in comparison to rice-fallow rotation, and this is reflected in rice yield
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
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