1,721,101 research outputs found
Beetle biodiversity in anthropogenic landscapes with a focus on spruce plantations, Christmas tree plantations and maize fields
No full textChange in saproxylic beetle, fungi and bacteria assemblages along horizontal and vertical gradients of sun-exposure in forest
No full textCoverage based diversity estimates of facultative saproxylic species highlight the importance of deadwood for biodiversity
No full texthttp://dx.doi.org/10.13039/501100013549 Bundesministerium für Umwelt, Naturschutz, nukleare Sicherheit und Verbraucherschutzhttp://dx.doi.org/10.13039/501100004937 BMBF Berlinhttp://dx.doi.org/10.13039/501100006549 Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheithttp://dx.doi.org/10.13039/501100002347 Bundesministerium für Bildung und Forschunghttp://dx.doi.org/10.13039/501100010415 Bundesamt für Naturschut
Beetle diversity is higher in sunny forests due to higher microclimatic heterogeneity in deadwood
No full textGerman Federal Ministry for the Environment, Nature Conservation and Nuclear Safet
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
12 years of assembly patterns in saproxylic beetles suggest early decay wood as ephemeral resource patch
No full textAbstract The ephemeral resource patch (ERP) concept provides a framework for understanding how finite, short‐lived resources shape community assembly processes at both patch and landscape scale. Some of these theories and principles can be applied to intermediate‐lived resources, such as deadwood, but this remains largely unexplored. We tested three ecological mechanisms of community assembly ( more‐individuals hypothesis , habitat‐heterogeneity hypothesis and habitat filtering ) to investigate whether beetle assemblages in deadwood fit the ERP concept. We tracked saproxylic beetle communities in experimental logs of Norway spruce ( Picea abies ), European silver fir ( Abies alba ) and beech ( Fagus sylvatica ) in the temperate mountain forest of the Bavarian Forest National Park over a 12‐year decomposition period, from the early decomposition stage until near‐complete resource depletion. Beetle abundance and number of species declined consistently in all tree species until the 4th year but increased again in spruce after ~8 years. Species richness (number of species controlled for abundance) showed inconsistent patterns over time: U‐shaped for spruce, weakly hump‐shaped for fir and no temporal effect for beech. Habitat filtering was more pronounced in the early stage as functional diversity was initially low but increased for all tree species up to 4 years, then plateaued and increased again after ~10 years for both conifers. Conditional inference tree identified two temporally distinct beetle assemblages (years 1–3 and 4–12), and strong differences within the first 4 years. Our findings suggest that the more‐individuals hypothesis and habitat filtering are key mechanisms driving community assembly in saproxylic beetles. Early decomposition stages supported functionally similar assemblages, highlighting this phase as a critical period for decomposer community structuring. Synthesis . The consistency of the early successional trajectories of beetles suggests that the early stages of deadwood decomposition up to the 3rd year in the temperate zone follow ephemerality theories similar to those of short‐lived ERPs, while the advanced stages provide a habitat for a more random combination of beetle species. Furthermore, our findings highlight the need for temporally continuous deadwood input, via natural processes or staggered retention during logging operations, to provide coarse woody debris for wide range of saproxylic beetles.European Regional Development Fund https://doi.org/10.13039/501100008530Bundesamt für Naturschutz https://doi.org/10.13039/501100010415Bundesministerium für Umwelt, Naturschutz, nukleare Sicherheit und Verbraucherschutz https://doi.org/10.13039/50110001354
Canopy cover and forest management shape vertebrate scavenger assembly but not carrion removal rates
No full texthttp://dx.doi.org/10.13039/501100001659 Deutsche Forschungsgemeinschaf
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