Digital repository of Slovenian research organisations

Search the repository
A+ | A- | Help | SLO | ENG

Query: search in
search in
search in
search in

Options:
  Reset


Query: "keywords" (oak) .

1 - 10 / 13
First pagePrevious page12Next pageLast page
1.
Pedunculate oak (Quercus robur L.) in Bosnia and Herzegovina - state and perspectives
Mirzeta Memišević Hodžić, Dalibor Ballian, 2023, original scientific article

Abstract: Bosnia and Herzegovina is located in Southeast Europe, and more than half its area of 51.129 km² belongs to forests and forest lands. 93% of the forests of Bosnia and Herzegovina are natural forests and have many plant species, many of which are endemic. There are eight oak species growing in Bosnia and Herzegovina. The most important ones are Quercus robur (despite being almost extinct due to overexploitation during the late XIX and early XX century), and Quercus petraea. Pedunculate oak in Bosnia and Herzegovina is found in mixed stands with common hornbeam and in pure stands under exceptional conditions, with a total area of about 30,000 ha. In this paper, the data of the studies carried out in the pedunculate oak forests of Bosnia and Herzegovina were compiled and a general evaluation was made. The results of phenological observation in pedunculate oak provenance test in Bosnia and Herzegovina through the years showed statistically significant differences among provenances in the beginning, end and duration of individual phenological phases. Researches on growth showed overtaking of provenances through the years, and best results in provenance Jelah for the most of investigated years. The research results on showed a significant positive correlation between the height and root collar diameter in provenance test and most of the investigated .The remaining pedunculate oak populations in Bosnia and Herzegovina have a good genetic structure and can be used as a seed stands for collecting seed material and producing seedlings for afforestation with this species
Keywords: Pedunculate oak, Bosnia and Herzegovina, afforestation
Published in DiRROS: 25.03.2024; Views: 36; Downloads: 17
.pdf Full text (1,04 MB)
This document has many files! More...

2.
The economic outcomes of high pedunculate oak (Quercus robur L.) forest management in Croatia
Stjepan Posavec, Karlo Beljan, Ivica Milković, 2023, published scientific conference contribution

Keywords: economic valuation, long-term investment, revenues, costs, oak stands
Published in DiRROS: 06.10.2023; Views: 210; Downloads: 73
.pdf Full text (118,45 KB)

3.
Preliminary assessment of genetic gain through the selection of different pedunculate oak populations in provenance test
Dalibor Ballian, Mirzeta Memišević Hodžić, 2022, original scientific article

Abstract: The distribution of pedunculate oak in Bosnia and Herzegovina is important in connecting the southern and eastern provenances of the Balkan Peninsula with provenances from Central Europe. However, due to over-exploitation, pedunculate oak is almost extinct in Bosnia and Herzegovina. This research aims to determine the heredity and production potential of the pedunculate oak from 28 provenances in the Bosnian-Herzegovinian provenance test through the genetic gain of thickness and height growth. The results will be used in selection of best provenances in terms of genetic gain. For this research, height and root collar diameter of pedunculate oak plants in Bosnian-Herzegovinian provenance tests were measured in 2012, 2016 and 2020. The provenance test was established in 2009. It contains 28 provenances from Bosnia and Herzegovina. Heredity and selection differentialwere assessed using analysis of variance. Possible genetic gain if using five best and one best provenance were determined. The results of the genetic gain for height obtained using data from 2012 and 2020 were low. The results obtained for 2016 indicate that the genetic gain for height, using five best provenances would be 7.62%, and using the best provenance 9.98%. Results of the genetic gain for root collar diameter obtained for 2016 and 2020 were low. For2012, the genetic improvement using five best provenances would be 4.28%, and using the best provenance 6.32%. The results indicate that by selecting the best provenances of pedunculate oak and their propagation, we can achieve a significant increase in plant height and thickness, i.e., the yield of wood mass. As research concerns juvenile material, it is necessary to continue systematic monitoring, to determine the actual heredity and genetic age, when the trees reach their physiological maturity, and when the annual value oscillations become uniform
Keywords: Pedunculate oak, genetic gain
Published in DiRROS: 08.03.2023; Views: 352; Downloads: 134
.pdf Full text (682,55 KB)
This document has many files! More...

4.
Where to search: the use of opportunistic data for the detection of an invasive forest pest
Maarten De Groot, Nikica Ogris, Mark van der Meij, Michael J.O. Pocock, 2022, original scientific article

Abstract: Early detection is important for the management of invasive alien species. In the last decade citizen science has become an important source of such data. Here, we used opportunistic records from the “LIFE ARTEMIS” citizen science project, in which people submitted records from places where they observed tree pests, to understand the distribution of a rapidly-spreading forest pest: the oak lace bug (Corythucha arcuata) in Slovenia. These citizen science records were not distributed randomly. We constructed a species distribution model for C. arcuata that accounted for the biased distribution of citizen science by using the records of other tree pests and diseases from the same project as pseudo-absences (so-called constrained pseudo-absences), and compared this to a model with pseudo-absences selected randomly from across Slovenia. We found that the constrained pseudo-absence model showed that C. arcuata was more likely to be found in east, in places with more oak trees and at lower elevations, and also closer to highways and railways, indicating introduction and dispersal by accidental human transport. The outputs from the model with random pseudo-absences were broadly similar, although estimates from this model tended to be higher and less precise, and some factors that were significant (proximity to minor roads and human settlements) were artefacts of recorder bias, showing the importance of taking the distribution of recording into account wherever possible. The finding that C. arcuata is more likely to be found near highways allows us to design advice for where future citizen science should be directed for efficient early detection.
Keywords: Oak lace bug, ecological modelling, citizen science, invasive alien species, early detection, Corythucha arcuata
Published in DiRROS: 08.09.2022; Views: 469; Downloads: 234
.pdf Full text (2,79 MB)
This document has many files! More...

5.
Genetic variability of pedunculate oak (Quercus robur L.) at the Mediterranean margin of the distribution range
Mirzeta Memišević Hodžić, Barbara Fussi, Dušan Gömöry, Dalibor Ballian, 2021, review article

Abstract: In Bosnia and Herzegovina, pedunculate oak (Quercus robur L.) occurs at the southern margin of its distribution range, close to the glacial refugia of this species. To assess the patterns of genetic diversity distribution at the rear edge of the Holocene colonization, we studied genetic variation in 20 pedunculate oak populations using 14 allozyme loci. Despite considerable differences among populations, neither the numbers of alleles nor genetic diversity showed any geographical trend within the studied area, although small isolated populations showed generally lower allelic richness. The Bayesian analysis of population structure indicated a kind of geographical pattern. We identified no signs of a recent bottleneck. The proximity to multiple glacial refugia explains the outcomes.
Keywords: pedunculate oak, allozyme, genetic variability, marginal populations, rear edge
Published in DiRROS: 22.07.2022; Views: 496; Downloads: 240
.pdf Full text (833,22 KB)
This document has many files! More...

6.
Climatic regulation of leaf and cambial phenology in Quercus pubescens : their interlinkage and impact on xylem and phloem conduits
Jožica Gričar, Jernej Jevšenak, Polona Hafner, Peter Prislan, Mitja Ferlan, Martina Lavrič, Dominik Vodnik, Klemen Eler, 2022, original scientific article

Abstract: Increased frequency and severity of stressful events affects the growth patterns and functioning of trees which adjust their phenology to given conditions. Here, we analysed environmental effects (temperature, precipitation, VPD and SWC) on the timing of leaf phenology, seasonal stem radial growth patterns, and xylem and phloem anatomy of Quercus pubescens in the sub-Mediterranean in the period 2014%2019, when various adverse weather events occurred, i.e. spring drought in 2015, summer fire in 2016 and summer drought in 2017. Results showed that the timings of leaf and cambium phenology do not occur simultaneously in Q. pubescens, reflecting different environmental and internal constraints. Although year-to-year variability in the timings of leaf and cambial phenology exists, their chronological sequence is fairly fixed. Different effects of weather conditions on different stages of leaf development in spring were observed. Common climatic drivers (i.e., negative effect of hot and dry summers and a positive effect of increasing moisture availability in winter and summer) were found to affect the widths of xylem and phloem increments with more pronounced effect on late formed parts. A legacy effect of the timing of leaf and cambial phenology of the previous growing season on the timing of phenology of the following spring was confirmed. Rarely available phloem data permitted a comprehensive insight into the interlinkage of the timing of cambium and leaf phenology and adjustment strategies of vascular tissues in Mediterranean pubescent oak to various environmental constraints, including frequent extreme events (drought, fire). Our results suggest that predicted changes in autumn/winter and spring climatic conditions for this area could affect the timings of leaf and stem cambial phenology of Q. pubescens in the coming years, which would affect stem xylem and phloem structure and hydraulic properties, and ultimately its performance.
Keywords: pubescent oak, leaf development, radial growth, initial earlywood vessel, sieve tube, anatomy, cambial cell production, extreme weather events
Published in DiRROS: 06.09.2021; Views: 931; Downloads: 265
.pdf Full text (7,00 MB)
This document has many files! More...

7.
Isotopic and water relation responses to ozone and water stress in seedlings of three oak species with different adaptation strategies
Claudia Cocozza, Elena Paoletti, Tanja Mrak, Saša Zavadlav, Tom Levanič, Hojka Kraigher, Alessio Giovannelli, Yasutomo Hoshika, 2020, original scientific article

Abstract: The impact of global changes on forest ecosystem processes is based on the species-specific responses of trees to the combined effect of multiple stressors and the capacity of each species to acclimate and cope with the environment modification. Combined environmental constraints can severely affect plant and ecological processes involved in plant functionality. This study provides novel insights into the impact of a simultaneous pairing of abiotic stresses (i.e., water and ozone (O3) stress) on the responses of oak species. Water stress (using 40 and 100% of soil water content at field capacity - WS and WW treatments, respectively) and O3 exposure (1.0, 1.2, and 1.4 times the ambient concentration - AA, 1.2AA, and 1.4AA, respectively) were carried out on Quercus robur L., Quercus ilex L., and Quercus pubescens Willd. seedlings, to study physiological traits (1. isotope signature [delta 13C, delta 18O and delta 15N], 2. water relation [leaf water potential, leaf water content], 3. leaf gas exchange [light-saturated net photosynthesis, Asat, and stomatal conductance, gs]) for adaptation strategies in a Free-Air Controlled Exposure (FACE) experiment. Ozone decreased Asat in Q. robur and Q. pubescens while water stress decreased it in all three oak species. Ozone did not affect delta 13C, whereas delta 18O was influenced by O3 especially in Q. robur. This may reflect a reduction of gs with the concomitant reduction in photosynthetic capacity. However, the effect of elevated O3 on leaf gas exchange as indicated by the combined analysis of stable isotopes was much lower than that of water stress. Water stress was detectable by delta 13C and by delta 18O in all three oak species, while delta 15N did not define plant response to stress conditions in any species. The delta 13C signal was correlated to leaf water content (LWC) in Q. robur and Q. ilex, showing isohydric and anisohydric strategy, respectively, at increasing stress intensity (low value of LWC). No interactive effect of water stress and O3 exposure on the isotopic responses was found, suggesting no cross-protection on seasonal carbon assimilation independently on the species adaptation strategy.
Keywords: ozone, gas exchange, English oak, holm oak, downy oak, Quercus ilex L., Quercus robur L., Quercus pubescens Willd
Published in DiRROS: 11.08.2020; Views: 1728; Downloads: 1063
URL Link to full text
This document has many files! More...

8.
Timeline of autumn phenology in temperate deciduous trees
Inge Dox, Jožica Gričar, Lorène Julia Marchand, Sebastien Leys, Paolo Zuccarini, Charly Geron, Peter Prislan, Bertold Mariën, Patrick Fonti, Holger Lange, Josep Peñuelas, Jan Van den Bulcke, Matteo Campioli, 2020, original scientific article

Abstract: Cessation of xylem formation or wood growth (CWG) and onset of foliar senescence (OFS) are key autumn phenological events in temperate deciduous trees. Their timing is fundamental for development and survival of trees, ecosystem nutrient cycling, the seasonal exchange of matter and energy between the biosphere and atmosphere and affect the impact and feedback of forests to global change. A large-scale experimental effort and improved observational methods have allowed us to compare the timing of CWG and OFS for different deciduous tree species in Western Europe, in particularly silver birch, a pioneer species, and European beech, a late-succession species, at stands of different latitudes, of different levels of site fertility, and for two years with contrasting meteorological and drought conditions i.e., the low-moderately dry 2017 and the extremely dry 2018. Specifically, we tested whether foliar senescence started before, after or concurrently with CWG. OFS and CWG occurred generally between late September and early November, with larger differences across species and sites for OFS. Foliar senescence started concurrently with CWG in most cases, except for the drier 2018 and, for beech, at the coldest site, where OFS occurred significantly later than CWG. Behavior of beech in Spain, the southern edge of its European distribution, was unclear, with no CWG, but very low wood growth at the time of OFS. Our study suggests that OFS is generally triggered by the same drivers of CWG or when wood growth decreases in late summer, indicating an overarching mechanism of sink limitation as a possible regulator of the timing of foliar senescence.
Keywords: autumn phenology, xylem formation, foliar senescence, cambium, chlorophyll, radial growth, wood, decidiuous trees, common aspen, common beech, pedunculate oak, silver birch
Published in DiRROS: 10.06.2020; Views: 1874; Downloads: 1122
.pdf Full text (2,04 MB)
This document has many files! More...

9.
Inter-individual variability in spring phenology of temperate deciduous trees depends on species, tree size and previous year autumn phenology
Lorène Julia Marchand, Inge Dox, Jožica Gričar, Peter Prislan, Sebastien Leys, Jan Van den Bulcke, Patrick Fonti, Holger Lange, Erik Matthysen, Josep Peñuelas, Paolo Zuccarini, Matteo Campioli, 2020, original scientific article

Abstract: We explored the inter-individual variability in bud-burst and its potential drivers, in homogeneous mature stands of temperate deciduous trees. Phenological observations of leaves and wood formation were performed weekly from summer 2017 to summer 2018 for pedunculate oak, European beech and silver birch in Belgium. The variability of bud-burst was correlated to previous' year autumn phenology (i.e. the onset of leaf senescence and the cessation of wood formation) and tree size but with important differences among species. In fact, variability of bud-burst was primarily related to onset of leaf senescence, cessation of wood formation and tree height for oak, beech and birch, respectively. The inter-individual variability of onset of leaf senescence was not related to the tree characteristics considered and was much larger than the inter-individual variability in bud-burst. Multispecies multivariate models could explain up to 66% of the bud-burst variability. These findings represent an important advance in our fundamental understanding and modelling of phenology and tree functioning of deciduous tree species.
Keywords: leaf unfolding, wood formation, coloration, Pedunculate oak, European beech, Silver birch
Published in DiRROS: 10.06.2020; Views: 1819; Downloads: 1056
URL Link to full text
This document has many files! More...

10.
Post-fire effects on development of leaves and secondary vascular tissues in Quercus pubescens
Jožica Gričar, Polona Hafner, Martina Lavrič, Mitja Ferlan, Nives Ogrinc, Bor Krajnc, Klemen Eler, Dominik Vodnik, 2020, original scientific article

Abstract: An increased frequency of fire events on the Slovenian Karst is in line with future climate-change scenarios for drought-prone environments worldwide. It is therefore of the utmost importance to better understand tree-fire-climate interactions for predicting the impact of changing environment on tree functioning. To this purpose, we studied the post-fire effects on leaf development, leaf carbon isotope composition (%13C), radial growth patterns and the xylem and phloem anatomy in undamaged (H-trees) and fire-damaged trees (F-trees) of Q. pubescens with good re-sprouting ability in spring 2017, the growing season after a rangeland fire in August 2016. We found that the fully developed canopy of F-trees reached only half of the LAI values measured in H-trees. Throughout the season, F-trees were characterised by higher water potential and stomatal conductivity and achieved higher photosynthetic rates compared to unburnt H-trees. The foliage of F-trees had more negative %13C values than those of H-trees. This reflects that F-trees less frequently meet stomatal limitations due to reduced transpirational area and more favourable leaf-to-root ratio. In addition, the growth of leaves in F-trees relied more on the recent photosynthates than on reserves due to the fire disturbed starch accumulation in the previous season. Cambial production stopped 3 weeks later in F-trees, resulting in 60% and 22% wider xylem and phloem increments, respectively. A novel approach by including phloem anatomy in the analyses revealed that fire caused changes in conduit dimensions in the early phloem but not in the earlywood. However, premature formation of the tyloses in the earlywood vessels of the youngest two xylem increments in F-trees implies that xylem hydraulic integrity was also affected by heat. Analyses of secondary tissues showed that although xylem and phloem tissues are interlinked changes in their transport systems due to heat damage are not necessarily coordinated.
Keywords: pubescent oak, cambium, radial growth, xylem, phloem, anatomy, sub-Mediterranean
Published in DiRROS: 19.03.2020; Views: 2382; Downloads: 1272
.pdf Full text (732,75 KB)
This document has many files! More...

Search done in 0.35 sec.
Back to top