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Presoja varovalnega učinka gozda pred drobirskimi tokovi ob Savi Bohinjki v Soteski
Full text linkVarovalni gozdovi imajo pomembno vlogo pri zmanjševanju učinka različnih naravnih nevarnosti. V Sloveniji imamo 10 % varovalnih gozdov, 30 % teh gozdovima zaščitno funkcijo. Preučili smo učinkovitost varovalnih gozdov na severozahodu Slovenije, v Soteski med Bledom in Bohinjem, kjer sta ogroženi državna cesta in železnica. Na podlagi geološke karte in karte podvrženosti drobirskim tokovom smo ugotovili vplivno območje drobirskih tokov. Pri modeliranju njihovega širjenja smo uporabili program TopRunDF. Podatke o gozdu smo zbrali na 47 vzorčnih ploskvah, kjer smo izmerili vsa živa drevesa s prsnim premerom ? 10 cm. Podrobno smo opisali sestoje in jih ovrednotili po metodi NaiS. Ugotovili smo, da ima gozd ključno vlogo pri zaščiti infrastrukturnih objektov. Za trajno zaščitno vlogo v enomernih sestojih je potrebno gojenje mozaično raznomernega gozda. V sestojih, kjer gozdnogojitveni ukrepi ne zadostujejo, je potrebno uporabiti tehnične ukrepe. Ker s sestoji niso gospodarili več desetletij so motnje (najpogosteje v obliki vetrolomov) pogoste. Izsledki kažejo, da je potrebno ovrednotenje varovalne in zaščitne funkcije teh gozdov. Priporočamo tudi aktivno nego, kar je v nasprotju z dosedanjo prakso negospodarjenja teh gozdov.Protection forests have an important role of mitigating the influence of various natural hazards. Only 10% of all forests in Slovenia have an indirect protection function, while 30% of them perform a direct protection role. Studyof protection efficiency of beech dominated forests in the Soteska gorge in NW Slovenia, where a main state road and railway are endangered was done. We assessed the starting impacts of the debris-flow natural hazard based on a small-scale geological survey of the terrain characteristics and local debris flow susceptibillity map. For determination of the run-out zones we used the TopRunDF model. Forest structure data was obtained from 47 sample plots where all trees with DBH ? 10 cm were measured. A detailed description and delineation of forest stands was performed. Results showed that the forests stands play a crucial role in protection of infrastructural objects. For long-term protection efficiency, spatially-explicit regeneration patches are needed in uniform forest stands. In areas where silvicultural measures could not provide sufficient protection, technical measures are needed. Since these forests have not been managed for several decades, natural disturbances are frequent. Research findings suggest that assessment and management of these beech dominated protection forests is necessary, contrary to the current practice of non-management in protection forests in Slovenia
Post-disturbance treatments and stand restoration success in beech forest sites
Full text linkDoktorska disertacija je sestavljena iz treh sklopov. V prvem sklopu smo proučili vplive tehnične sanacije (posek in spravilo) na obnovo vegetacije po ujmah manjših do srednjih jakosti v mešanih, pretežno bukovih sestojih na osmih raziskovalnih objektih po Sloveniji, kjer je bila na delu površine opravljena tehnična sanacija, medtem ko preostali del ni bil saniran. Raziskava je pokazala, da med načinoma dela ni bilo bistvenih razlik v gostotah, višinski strukturi in hitrosti rasti mladja. Majhne razlike nakazujejo, da je na predelih brez tehnične sanacije nekoliko več bolj razvitega oz. višjega mladja, ki se je verjetno ohranilo iz prejšnjega sestoja, medtem ko je na saniranih predelih nekoliko več manj razvitega oz. nižjega mladja svetloljubnih drevesnih vrst, ki je lahko vraščalo zaradi odstranjenih drevesnih ostankov in majhnih poškodb tal pri spravilu. Tehnična sanacija po ujmah majhnih do srednjih jakosti v mešanih, pretežno bukovih sestojih ni imela negativnih vplivov na obnovo vegetacije. V drugem sklopu smo proučili razlike med naravno in umetno obnovo na treh raziskovalnih območjih, ki jih je leta 2008 prizadel vetrolom. Osnovali smo ploskve na mestih naravne obnove, kjer smo popisovali dominantne osebke naravnega mladja, na mestih umetne obnove pa sadike. Znotraj obeh tipov ploskev smo postavili ploskvice za analizo vegetacije, kjer smo popisali pokrovnost zeliščne vegetacije in gostote naravnega mladja. Rezultati kažejo, da je bila naravna obnova različno uspešna. Na območju Trnovski gozd je bila pomanjkljiva zaradi zaostrenih ekoloških razmer, na zgornjem delu Črnivca zaradi goste travne ruše vijugave masnice, na Bohorju pa je bila uspešna. Gostote naravnega pomladka so bile na ploskvah z umetno obnovo od tri- do štirikrat nižje kot na ploskvah naravne obnove, kar je verjetno posledica obžetev sadik, s čimer se verjetno odstrani samoniklo mladje. V tretjem sklopu smo proučili dolgotrajno drugotno sukcesijo po požaru na Mozirski Požganiji. Leta 2013 smo ponovili meritve stalnih vzorčnih ploskev, ki so bile prvič premerjene leta 1981. Izsledki kažejo, da so na preživetje dreves ključno vplivale drevesna vrsta, višina, drevesna plast in globina krošnje. Smreka je imela najvišjo stopnjo preživetja, sledijo breza, trepetlika in iva. Visok začetni delež smreke in povečevanje njenega deleža kažeta na pionirske lastnosti smreke, ki v začetnem obdobju brez težav tekmuje z drugimi pionirji, kasneje pa se uveljavi kot poznosukcesijska vrsta, ko se pionirji že umikajo iz sestojev.This dissertation comprises three studies. In the first study we examined the influence of salvage logging on forest regeneration following small to medium-scale moderate severity disturbances in eight mixed beech (Fagus sylvatica L.) dominated forest stands in Slovenia where part of the disturbed area was salvaged and the adjacent part was not salvaged. Results show that there were no significant differences in terms of densities, height structure and regeneration growth between treatments. Minor differences indicate that the non-salvaged sites tended to have a slightly more well-developed (taller) regeneration layer that remained from the previous stand and was not damaged during harvesting, while salvaged sites had a larger proportion of shade intolerant tree species due to the removal of damaged timber, which created minor soil disturbances and space for easier recruitment of regeneration. The results suggest that salvage logging following small-scale intermediate severity disturbances may not hinder forest recovery in mixed beech dominated forests. In the second study we analyzed the differences between planted and natural regeneration on three research areas disturbed by storms in 2008. We established sampling plots of natural regeneration where the dominant trees of the natural regeneration were measured and sampling plots with artificial regeneration where all planted seedlings were measured. Within both plot types, smaller vegetation subplots were established where the cover of each plant species was estimated and natural regeneration was counted. Results show that the success of the natural regeneration varied between research areas and study sites. Natural regeneration densities in Trnovski gozd were not sufficient due to the more extreme ecological conditions, while at the Bohor area the densities were high. On the upper slope of Črnivec, the natural regeneration was inhibited by thick grass of Deschampsia flexuosa (L.) Trin. Average densities of natural regeneration were 3-4 times higher on the plots with natural regeneration, which may be due to collateral damage to natural regeneration during ground vegetation removal on planted sites. In the third part of the dissertation, we studied secondary succession after forest fire at Mozirska Požganija. In 2013 we remeasured the plots established and inventoried in 1981. Results indicate that tree species, height, layer and crown depth positively influenced tree survival. Spruce showed the highest survival probability, followed by Betula pendula (Roth.), Populus tremula (L.) and Salix caprea (L.). The high initial proportion of spruce and its increasing share indicates the pioneer characteristics of a species that can easily compete with pioneers and later establish as a late successional species after pioneers retreat from the stands
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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