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Iskalni niz: "ključne besede" (diversity) .

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Genetic diversity of core vs. peripheral Norway spruce native populations at a local scale in Slovenia
Hojka Kraigher, Gregor Božič, Marjana Westergren

Povzetek: We investigated the levels of genetic diversity and population differentiation among core and peripheral populations of Norway spruce along an altitudinal gradient (from inversions to upper tree line) using isoenzymes (ISO) and nuclear simple-sequence repeats (SSR) markers on overlapping set of populations. Twenty-seven to seventy trees from 11 and 7 populations were genotyped with isoenzymes and SSRs, respectively. The results partially conform to the expectations of the central-peripheral hypothesis (CPH) and are consistent for both marker sets. Genetic differentiation among peripheral populations was low but significantly different from zero (FST-ISO = 0.013, FST-SSR = 0.009) and higher than that among core populations (FST-ISO = 0.007, FST-SSR = 0.005), conforming to central peripheral hypothesis. Contrastingly, levels of genetic diversity assessed by both richness and equitability measures did not significantly differ between peripheral and core populations (AR-ISO = 2.20 vs. 2.14, AR-SSR = 17.16 vs. 17.68, HE-ISO = 0.183 vs. 0.185, and HE-SSR = 0.935 vs. 0.935 for peripheral and core populations, respectively).
Ključne besede: central peripheral hypothesis, Picea abies (L.) Karst., genetic diversity, genetic differentiation, upper tree line, inversion
DiRROS - Objavljeno: 07.05.2018; Ogledov: 1160; Prenosov: 496
.pdf Celotno besedilo (561,16 KB)

Effects of disturbance on understory vegetation across Slovenian forest ecosystems
Lado Kutnar, Thomas Andrew Nagel, Janez Kermavnar, 2019

Povzetek: The herbaceous understory represents a key component of forest biodiversity across temperate forests of Europe. Here, we quantified changes in the diversity and composition of the forest understory layer in representative Slovenian forest ecosystems between 2004/05 and 2014/15. In total, 60 plots were placed across 10 different managed forest types, ranging from lowland deciduous and mid-altitude mesic mixed forests to mountain conifer forests. This network is part of an international network of sites launched within the ICP Forests Programme aimed to assess the condition of forests in Europe. To examine how disturbance influenced understory dynamics, we estimated the disturbance impacts considering both natural and/or anthropogenic disturbances that cause significant damage to trees and to ground-surface layers, including ground-vegetation layers and upper-soil layers. Species richness across 10 sites (gamma diversity) significantly decreased from 272 to 243 species during the study period, while mean species richness per site did not significantly change. The mean value of site level Shannon diversity indices and evenness significantly increased. The cover of most common plant species increased during the monitoring period. The mean value of disturbance estimates per site increased from 0.8% in 2004/05 (ranging from 0% to 2.5%) to 16.3% in 2014/15 (ranging from 5.0% to 38.8%), which corresponded to a reduction in total vegetation cover, including tree-layer cover. More disturbed sites showed larger temporal changes in species composition compared to less disturbed sites, suggesting that forest disturbances caused understory compositional shifts during the study period. Rather than observing an increase in plant diversity due to disturbance, our results suggest a short-term decrease in species number, likely driven by replacement of more specialized species with common species.
Ključne besede: vegetation dynamics, vascular-plant diversity, understory layer, disturbance, monitoring, temperate forests
DiRROS - Objavljeno: 27.11.2019; Ogledov: 557; Prenosov: 318
URL Celotno besedilo (0,00 KB)

Using genomic information for management planning of an endangered perennial, Viola uliginosa
Kyung Min Lee, Pertti Ranta, Jarmo Saarikivi, Lado Kutnar, Branko Vreš, Maxim Dzhus, Marko Mutanen, Laura Kvist, 2020

Povzetek: Species occupying habitats subjected to frequent natural and/or anthropogenic changes are a challenge for conservation management. We studied one such species, Viola uliginosa, an endangered perennial wetland species typically inhabiting sporadi-cally flooded meadows alongside rivers/lakes. In order to estimate genomic diversity, population structure, and history, we sampled five sites in Finland, three in Estonia, and one each in Slovenia, Belarus, and Poland using genomic SNP data with double-digest restriction site-associated DNA sequencing (ddRAD-seq). We found mono-phyletic populations, high levels of inbreeding (mean population FSNP = 0.407-0.945), low effective population sizes (Ne = 0.8-50.9), indications of past demographic ex-pansion, and rare long-distance dispersal. Our results are important in implementing conservation strategies for V. uliginosa, which should include founding of seed banks, ex situ cultivations, and reintroductions with individuals of proper origin, combined with continuous population monitoring and habitat management.
Ključne besede: nature conservation, demography, genomic diversity, population genomics, RAD sequencing, Viola
DiRROS - Objavljeno: 20.02.2020; Ogledov: 195; Prenosov: 110
URL Celotno besedilo (0,00 KB)

The interplay between forest management practices, genetic monitoring, and other long-term monitoring systems
Darius Kavaliauskas, Barbara Fussi, Marjana Westergren, Filipos Aravanopoulos, Domen Finžgar, Roland Baier, Paraskevi Alizoti, Gregor Božič, Evangelia V. Avramidou, Monika Konnert, Hojka Kraigher, 2018

Povzetek: The conservation and sustainable use of forests and forest genetic resources (FGR) is a challenging task for scientists and foresters. Forest management practices can affect diversity on various levels: genetic, species, and ecosystem. Understanding past natural disturbance dynamics and their level of dependence on human disturbances and management practices is essential for the conservation and management of FGR, especially in the light of climate change. In this review, forest management practices and their impact on genetic composition are reviewed, synthesized, and interpreted in the light of existing national and international forest monitoring schemes and concepts from various European projects. There is a clear need and mandate for forest genetic monitoring (FGM), while the requirements thereof lack complementarity with existing forest monitoring. Due to certain obstacles (e.g., the lack of unified FGM implementation procedures across the countries, high implementation costs, large number of indicators and verifiers for FGM proposed in the past), merging FGM with existing forest monitoring is complicated. Nevertheless, FGM is of paramount importance for forestry and the natural environment in the future, regardless of the presence or existence of other monitoring systems, as it provides information no other monitoring system can yield. FGM can provide information related to adaptive and neutral genetic diversity changes over time, on a species and/or on a population basis and can serve as an early warning system for the detection of potentially harmful changes of forest adaptability. In addition, FGM offers knowledge on the adaptive potential of forests under the changing environment, which is important for the long-term conservation of FGR
Ključne besede: forest monitoring, forest genetic monitoring, forest genetic diversity, silviculture
DiRROS - Objavljeno: 20.02.2020; Ogledov: 302; Prenosov: 200
URL Celotno besedilo (0,00 KB)
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Možnosti zaznavanja drevesnih vrst v okviru Monitoringa gozdov in gozdnih ekosistemov
Mitja Skudnik, Robert Brus, Anže Martin Pintar, 2020

Povzetek: Analizirali smo možnosti zaznavanja drevesnih vrst v okviru Monitoringa gozdov in gozdnih ekosistemov (MGGE) s poudarkom na manjšinskih in tujerodnih drevesnih vrstah ter možnosti zaznavanja razlik v pestrosti drevesnih vrst med posameznimi ekološkimi regijami. Zaznavanje minoritetnih in tujerodnih drevesnih vrst bi lahko izboljšali z obsežnejšim šifrantom drevesnih vrst, katerega dopolnitve smo predlagali. Take drevesne vrste bi zajeli z večjo verjetnostjo pri gostejši vzorčni mreži od obstoječe (4 km % 4 km). Opozorili smo tudi na pomen pravilne determinacije drevesne vrste na vzorčni ploskvi. V okviru MGGE smo ugotovili razlike v pestrosti drevesnih vrst med ekološkimi regijami; kot najpestrejša se je pokazala submediteranska ekološka regija.
Ključne besede: monitoring gozdov, gozdna inventura, seznam drevesnih vrst, manjšinske drevesne vrste, tujerodne drevesne vrste, pestrost drevesnih vrst, tree species diversity, non-native tree species
DiRROS - Objavljeno: 02.05.2020; Ogledov: 266; Prenosov: 114
.pdf Celotno besedilo (364,69 KB)

Eutypella parasitica and other frequently isolated fungi in wood of dead branches of young Sycamore Maple (Acer pseudoplatanus) in Slovenia
Ana Brglez, Barbara Piškur, Nikica Ogris, 2020

Povzetek: Eutypella parasitica R.W. Davidson and R.C. Lorenz is the causative agent of Eutypella canker of maple, a destructive disease of maples in Europe and North America. The fungus E. parasitica infects the trunk through a branch stub or bark wound. Because the fungal community may have an impact on infection and colonization by E. parasitica, the composition of fungi colonizing wood of dead branches of sycamore maple (Acer pseudoplatanus L.) was investigated in five sampling sites in Slovenia. Forty samples from each sampling site were collected between the November 2017 and March 2018 period. Isolations were made from the wood in the outer part of dead branches and from discoloured wood in the trunk that originated from a dead branch. Pure cultures were divided into morphotypes, and one representative culture per morphotype was selected for further molecular identification. From a total of 2700 cultured subsamples, 1744 fungal cultures were obtained, which were grouped into 212 morphotypes. The investigated samples were colonized by a broad spectrum of fungi. The most frequently isolated species were Eutypa maura (Fr.) Sacc., Eutypa sp. Tul. and C. Tul., Fusarium avenaceum (Fr.) Sacc., Neocucurbitaria acerina Wanas., Camporesi, E.B.G. Jones and K.D. Hyde and E. parasitica. In this study, we distinguished species diversity and the fungal community. There were no significant differences in the diversity of fungal species between the five sampling sites, and branch thickness did not prove to be a statistically significant factor in fungal species diversity. Nevertheless, relatively low Jaccard similarity index values suggested possible differences in the fungal communities from different sampling sites. This was confirmed by an analysis of similarities, which showed that the isolated fungal community distinctly differed between the five sampling sites and between the different isolation sources. Eutypella parasitica was isolated from all five investigated sampling sites, although Eutypella cankers were observed in only three sampling sites, indicating the possibility of asymptomatic infection.
Ključne besede: fungal composition, invasive species, diversity, fungal communities, molecular identification, frequencies, Jaccard similarity index, Eutypella parasitica, analysis of similarities, colonization
DiRROS - Objavljeno: 26.05.2020; Ogledov: 164; Prenosov: 117
URL Celotno besedilo (0,00 KB)
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Patterns of understory community assembly and plant trait-environment relationships in temperate SE European forests
Lado Kutnar, Janez Kermavnar, 2020

Povzetek: We analyzed variation in the functional composition and diversity of understory plant communities across different forest vegetation types in Slovenia. The study area comprises 10 representative forest sites covering broad gradients of environmental conditions (altitude, geology, light availability, soil type and reaction, nutrient availability, soil moisture), stand structural features and community attributes. The mean and variation of the trait values were quantified by community-weighted means and functional dispersion for four key plant functional traits: plant height, seed mass, specific leaf area and leaf dry matter content. At each study site, forest vegetation was surveyed at two different spatial scales (4 and 100 m2 ) in order to infer scale-dependent assembly rules. Patterns of community assembly were tested with a null model approach. We found that both trait means and diversity values responded to conspicuous gradients in environmental conditions and species composition across the studied forests. Our results mainly support the idea of abiotic filtering: more stressful environmental conditions (e.g., high altitude, low soil pH and low nutrient content) were occupied by communities of low functional diversity (trait convergence), which suggests a selective effect for species with traits adapted to such harsh conditions. However, trait convergence was also detected in some more resource-rich forest sites (e.g., low altitude, high soil productivity), most likely due to the presence of competitive understory species with high abundance domination. This could, at least to some extent, indicate the filtering effect of competitive interactions. Overall, we observed weak and inconsistent patterns regarding the impact of spatial scale, suggesting that similar assembly mechanisms are operating at both investigated spatial scales. Our findings contribute to the baseline understanding of the role of both abiotic and biotic constraints in forest community assembly, as evidenced by the non-random patterns in the functional structure of distinct temperate forest understories.
Ključne besede: functional composition, functional diversity, ecological gradients, abiotic filtering, trait convergence, trait divergence, spatial scale, forest ground-layer vegetation, Slovenia
DiRROS - Objavljeno: 26.05.2020; Ogledov: 143; Prenosov: 120
URL Celotno besedilo (0,00 KB)
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