1,720,956 research outputs found
ASSESSMENT OF BIOLOGICAL SOIL QUALITY IN LONG-TERM ORGANICALLY MANAGED VINEYARDS IN THE VERDICCHIO TERROIR OF MATELICA (MARCHE, ITALY)
Full text linkSoil biodiversity constitutes one of the main component of agroecosystems, being involved in the delivery of several essential ecosystem services such as, among others, nutrient cycling, soil formation, pest and pollution control. Thus, soil biodiversity indicators can be used by governments and farmers to monitor soil quality and ecosystem functioning under various land uses and management practices. At present, organic wine represents an emerging market that is showing potential for growth. There is, in fact, a growing worldwide interest and attention for environmental friendly products and sustainable agricultural practices. Organic farming employs a set of farming practices that contribute in preserving soil quality. In this scenario, the aim of our study was to assess the long-term effects of organically managed vineyards on soil quality by means of two bioindicators: ciliated protozoa and microarthropods. Ciliated protozoa are eukaryotic microorganisms which constitutes an essential component of the soil microbial loop. By feeding on bacterial biomass ciliates play an essential role in the liberation of nutrients in the plant rhizosphere. Soil microarthropods contribute to the organic matter degradation and dispersal, affect the soil porosity, aeration, water infiltration, modifying and improving soil fertility. Both ciliates and microarthropods are very sensitive to changes in their habitat and fluctuations in their communities can affect the food web and the energy transfer within the soil ecosystem. Thus, the monitoring of the structure of microarthropod and ciliate communities represent a valuable tool to assess soil quality and functioning. The study was realized in the terroir of “Verdicchio di Matelica” (Marche, Italy), on three vineyards that were organically managed since 1992, 1998 and 2009 respectively. In each vineyard, soil samples (0-10 cm depth) were taken every month from March to October 2011. In addition, soil chemical-physical (texture, soil moisture, pH, NPK, OM, C/N, Cu), were measured in each site. For microarthropods, the measured biological parameters were: the Soil Biological Quality (QBS-ar) index, abundances of biological (BF) and euedaphic forms (EF) and diversity indices. Soil samples were collected in both disturbed (tillage) and not-disturbed (no-tillage) inter-rows. For ciliates: abundances and diversity indices were measured and soil samples were randomly collected in the whole sampling area. The results of the multivariate data analysis (Cluster Analysis, CA; non-metric Multi-Dimensional Scaling, nMDS) and diversity indices (H’,J,d) indicate that the most stable habitat for ciliates and microarthropods is represented by the “older” (V92) followed by the V98 and the “younger” V09 vineyards. Collectively, the data seem to indicate that the long-term organic management of the soil contributes to global soil quality in vineyards at least in this particular pedoclimatic area and for the investigated bioindicators. Furthermore, this study helps in the definition of possible biotic baseline values to evaluate soil quality and health in vineyards
BIOLOGICAL SOIL QUALITY INDICATORS AND SUSTAINABLE VITICULTURE: A CASE STUDY IN THE VERDICCHIO TERROIR OF MATELICA ( ITALY)
Full text linkThe aim of our study was to assess the long-term effects of organically managed vineyards on soil quality by means of two bioindicators: ciliated protozoa and microarthropods. The study was realized in the terroir of Verdicchio di Matelica (Marche, Italy), on three vineyards that were organically managed since 1992, 1998 and 2009 respectively. In each vineyard, soil samples (0-10 cm depth) were taken every month from March to October 2011. Soil chemical-physical parameters were measured. For microarthropods, the measured biological parameters were: the Soil Biological Quality (QBS-ar) index, abundances of biological and euedaphic forms and diversity indices. Soil samples were collected in both disturbed (tillage) and not-disturbed (no-tillage) inter-rows. For ciliates: abundances and diversity indices were measured and soil samples were randomly collected in the whole sampling area. The results of the multivariate data analysis and diversity indices (H’,J,d) indicate that the most stable habitat for ciliates and microarthropods is represented by the “older” (V92) followed by the V98 and the “younger” V09 vineyards. Collectively, the data seem to indicate that the long-term organic management of the soil contributes to global soil quality in vineyards at least in this particular pedoclimatic area and for the investigated bioindicators
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
Soil biodiversity and sustainable vineyards: hints from the analysis of microarthropods and ciliated protozoa communities
Full text linkSoil biodiversity constitutes one of the main components of agroecosystems, being involved in the delivery of several essential ecosystem services such as, among others, nutrient cycling, soil formation, pest and pollution control. Thus, soil biodiversity indicators can be used by governments and farmers to monitor soil quality and ecosystem functioning under various land uses and management practices. In this scenario, the aim of our study was to assess the long-term effects of organically managed vineyards on soil quality by means of two bioindicators: protozoan ciliates and microarthropods. The study was realized in the terroir of Verdicchio di Matelica (Marche, Italy), on three vineyards that were organically managed since 1992, 1998 and 2009 respectively. In each vineyard, soil samples (0-10 cm depth) were taken every month from March to October 2011. In addition, soil chemical-physical (texture, soil moisture, pH, NPK, OM, C/N, Cu), were measured in each site. For microarthropods, the measured biological parameters were: the Soil Biological Quality (QBS-ar) index, abundances of Biological (BF) and Euedaphic forms (EF) and diversity indices. Soil samples were collected in both disturbed (tillage) and not-disturbed (no-tillage) inter-rows. For ciliates: abundances and diversity indices were measured and soil samples were randomly collected in the whole sampling area. The results of the multivariate data analysis (Cluster Analysis, CA; non-metric Multi-Dimensional Scaling, nMDS) and diversity indices (H’,J,d) indicate that the most stable habitat for ciliates and microarthropods is represented by the “older” (V92) followed by the V98 and the “younger” V09 vineyards. Collectively, the data seem to indicate that the long-term organic management of the soil contributes to global soil quality in vineyards at least in this particular pedoclimatic area and for the investigated bioindicators. Furthermore, this study helps in the definition of possible biotic baseline values to evaluate soil quality/health in vineyards
THE BIOPRINT PILOT PROJECT: CILIATED PROTOZOA COMMUNITIES AS A TOOL TO ASSESS SOIL QUALITY IN AGROECOSYSTEMS AND NATURAL SITES OF MARCHE REGION (ITALY)
Full text linkIn the recent years the potential of ciliated protozoa, as indicators of soil quality has been highlighted by several studies. Thus, in the framework of the BioPrint Pilot Project and for the first time in Italy, we have investigated the biodiversity and the community structure of soil ciliates from agroecosystems and natural sites of Marche Region. The aims of our study were: i) to evaluate the capacity of ciliates to discriminate between different types of land uses; and ii) farming management practices; iii) to assess relationships among ciliate community and abiotic parameters. Soil samples were collected twice from 10 sites (5 natural sites: FORest; and 5 arable field: 3 ORGanic and 2 CONventional). Ciliate communities were studied by means of qualitative (non-flooded Petri dish) and quantitative methods. Soil chemical-physical (texture, CEC NPK, OM, C/N, soil moisture and temperature) parameters were measured. Qualitative ciliate analysis allowed us to identify a total of 59 species representing 29 genera and 12 orders (plus 10 new species for the science). ORG sites were the richest in species followed by CON and FOR. The mean values for H’ (2.6), d (3.4) and J (0.8) were significantly higher in ORG than in CON (H’=2.1; d=2.7; J=0.7) and FOR (H’=1.7; d=1.95; J=0.6) supporting the intermediate disturbance hypothesis. Multivariate analysis showed statistically significant differences between natural sites (FORest) and agricultural sites, as well as between the ORGanic and CONventional management farming systems. CCA analysis showed correlations between the distribution of species with environmental parameters indicating the importance of these parameters in shaping the ciliate communities in the different type sites. Altogether, these results showed the bioindicative potential of ciliate communities in discriminating between natural sites (FORests) and agroecosystems, as well as their capacity to discriminate, at least preliminary, between different management systems (ORG vs CON)
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
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