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Chronic anthropogenic disturbance mediates the biodiversity‐productivity relationship across stand ages in a large temperate forest region
No full textAbstract
Temperate forests, especially those in the densely populated regions of the world, are experiencing increasing levels of habitat degradation and biological impoverishment due to subtle but pervasive chronic anthropogenic disturbances including frequent and continuous grazing and extraction of non‐timber forest products. However, the effects of these subtle, chronic disturbances on the biodiversity‐productivity relationship have rarely been examined especially in forests at different development stages. Accordingly, this study explores how chronic anthropogenic disturbance affects the relationship between tree species diversity and forest productivity at different stand development stages in a large temperate forest region.
We used the human footprint index as a proxy for chronic human disturbance. Hierarchical Bayesian models were employed to assess the effects of chronic human disturbance on the relationship between tree diversity and forest productivity across different stand age. Several measures of diversity were employed, including taxonomic, functional and phylogenetic diversity.
Forest productivity consistently increased with taxonomic, functional and phylogenetic biodiversity; these biodiversity facets were the main drivers of forest productivity compared to stand age, chronic human disturbance and climate. However, the magnitude at which productivity increases with the increments of taxonomic and functional diversity diminishes with the increasing chronic disturbance, especially in younger stands. The effects of phylogenetic diversity on productivity did not vary with chronic disturbance, regardless of stand age.
Synthesis and applications
: Chronic human disturbance in a large temperate forest region reduces the increase in community productivity due to different facets of biodiversity, especially in young forests. The evidence suggests that the mitigation of chronic human disturbance and the conservation of biodiversity will be effective in sustaining essential ecosystem functions
Anthropogenic disturbance mediates soil water effect on diversity-productivity relationships in a temperate forest region
No full textBiodiversity and anthropogenic disturbances predominantly drive carbon sequestration rates across temporal scales in temperate forests
No full textCommunity diversity and composition affect ecosystem multifunctionality across environmental gradients in boreal and temperate forests
No full texthttp://dx.doi.org/10.13039/501100001809 National Natural Science Foundation of Chinahttp://dx.doi.org/10.13039/501100012166 National Key Research and Development Program of Chin
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
Environmental filtering drives biodiversity–spatial stability relationships in a large temperate forest region
No full textVariations 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
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