71. Timeline of autumn phenology in temperate deciduous treesInge 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: 1908; Downloads: 1150
 Full text (2,04 MB)
This document has many files! More... |
72. Inter-individual variability in spring phenology of temperate deciduous trees depends on species, tree size and previous year autumn phenologyLorène 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: 1857; Downloads: 1084
 Link to full text
This document has many files! More... |
73. Določanje vlažnosti drv z električnim uporovnim merilnikomPeter Prislan, Domen Arnič, Špela Ščap, Nike Krajnc, Aleš Straže, 2020, professional article Abstract: Vsebnost vode (vlažnost) je med pomembnejšimi kazalniki kakovosti drv. Za čim učinkovitejše in okolju prijazno delovanje Uredba o emisiji snovi v zrak iz malih kurilnih naprav navaja, da mora biti vsebnost vode v drveh manj kot 20 %. Za hitro preverjanje vsebnosti vode v drveh bi bila smiselna uporaba električnih uporovnih merilnikov. V pričujočem prispevku primerjamo meritve, opravljene z elektrouporovnimi merilniki različnih izvedb ter referenčno gravimetrično metodo. Rezultati kažejo, da gravimetrični metodi najbolj primerljive rezultate kažejo uporovni merilniki, ki omogočajo kompenzacijo gostote lesne vrste in temperature. V prispevku razpravljamo o uporabi različne terminologije in definicije lesne vlažnosti (t.j. relativna in absolutna vlažnost lesa, vsebnost vode) ter predlagamo postopek za čim boljšo oceno vlažnosti z enostavnimi elektro-uporovnimi merilniki.
Keywords: lesna goriva, lesna biomasa, vsebnost vode, kakovost drv
Published in DiRROS: 06.04.2020; Views: 2115; Downloads: 658
Full text (219,11 KB) |
74. Raba lesa v slovenskem biogospodarstvuDomen Arnič, Peter Prislan, Luka Juvančič, 2019, original scientific article Abstract: Krčenje zalog fosilnih goriv, netrajnostno izkoriščanje naravnih virov in podnebne spremembe so dejavniki, ki pospešujejo prehod v biogospodarstvo. Tovrsten prehod omogočajo tehnologije in novo znanje pretvorbe biomase v različne produkte, med seboj povezane v kaskadnih in (energetsko in snovno) krožnih proizvodnih ciklih. Eno ključnih področij biogospodarstva je področje rabe lesa, ki trenutno prispeva eno tretjino k skupni dodani vrednosti slovenskega biogospodarstva. Glede na stanje v državah s primerljivimi naravnimi in strukturnimi danostmi Slovenija v razvoju biogospodarstva zaostaja. V pričujočem delu smo predstavili generične dejavnike, ki vplivajo na razvoj biogospodarstva ter pripravili pregled stanja slovenskega biogospodarstva na področju rabe lesa. Stanje slovenskega biogospodarstva uvrščamo v širši evropski okvir ter ocenjujemo nadaljnje možnosti razvoja rabe lesa.
Keywords: biogospodarstvo, lesna biomasa, obnovljivi viri energije, raba lesa, biorafinerije, kaskadna raba lesa
Published in DiRROS: 20.12.2019; Views: 2620; Downloads: 757
Full text (422,48 KB) |
75. Kakovost pelet na slovenskem trgu 2015Peter Prislan, Nike Krajnc, Mitja Piškur, 2015, treatise, preliminary study, study Keywords: kakovost pelet, mehanska obstojnost, vsebnost vode, delež pepela, lastnosti pelet
Published in DiRROS: 12.07.2017; Views: 2549; Downloads: 727
Full text (10,55 MB)
This document has many files! More... |
76. Annual cambial rhythm in Pinus halepensis and Pinus sylvestris as indicator for climate adaptationPeter Prislan, Jožica Gričar, Martin De Luis, Klemen Novak, Edurne Martinez Del Castillo, Uwe Schmitt, Gerald Koch, Jasna Štrus, Polona Mrak, Magda Tušek-Žnidarič, Katarina Čufar, 2016, original scientific article Abstract: To understand better the adaptation strategies of intra-annual radial growth in Pinus halepensis and Pinus sylvestris to local environmental conditions, we examined the seasonal rhythm of cambial activity and cell differentiation at tissue and cellular levels. Two contrasting sites differing in temperature and amount of precipitation were selected for each species, one typical for their growth and the other represented border climatic conditions, where the two species coexisted. Mature P. halepensis trees from Mediterranean (Spain) and sub-Mediterranean (Slovenia) sites, and P. sylvestris from sub-Mediterranean (Slovenia) and temperate (Slovenia) sites were selected. Repeated sampling was performed throughout the year and samples were prepared for examination with light and transmission electron microscopes. We hypothesized that cambial rhythm in trees growing at the sub-Mediterranean site where the two species co-exist will be similar as at typical sites for their growth. Cambium in P. halepensis at the Mediterranean site was active throughout the year and was never truly dormant, whereas at the sub-Mediterranean site it appeared to be dormant during the winter months. In contrast, cambium in P. sylvestris was clearly dormant at both sub-Mediterranean and temperate sites, although the dormant period seemed to be significantly longer at the temperate site. Thus, the hypothesis was only partly confirmed. Different cambial and cell differentiation rhythms of the two species at the site where both species co-exist and typical sites for their growth indicate their high but different adaptation strategies in terms of adjustment of radial growth to environmental heterogeneity, crucial for long-term tree performance and survival.
Keywords: Aleppo pine, Pinus halepensis, Scots pine, Pinus sylvestris, cambium, light microscopy, Mediterranean environment, temporate environment, transmission electron microscopy, xylem
Published in DiRROS: 12.07.2017; Views: 3128; Downloads: 1425
Full text (4,63 MB)
This document has many files! More... |
77. "Za posavski gozd in les"Nike Krajnc, Matjaž Harmel, Špela Ščap, Aleksandra Krajnc, Matevž Triplat, Peter Prislan, Mitja Piškur, 2015, final research report Keywords: Posavje, gozdovi, lesna industrija, gozdno-lesna veriga
Published in DiRROS: 12.07.2017; Views: 2649; Downloads: 755
Full text (8,99 MB) |
78. Analiza potencialnih lokacij za nove dejavnostiAleksandra Krajnc, Matevž Triplat, Matjaž Harmel, Peter Prislan, Nike Krajnc, 2014, treatise, preliminary study, study Keywords: proizvodne dejavnosti, lesnopredelovalni obrati, industrija, prostorski načrti
Published in DiRROS: 12.07.2017; Views: 2422; Downloads: 796
Full text (25,97 MB) |
79. Kakovost pelet na slovenskem trgu 2014Peter Prislan, Nike Krajnc, Mitja Piškur, 2014, treatise, preliminary study, study Keywords: kakovost pelet, mehanska obstojnost, vsebnost vode, delež pepela
Published in DiRROS: 12.07.2017; Views: 2679; Downloads: 698
Full text (310,59 KB) |
80. Analiza vzorcev pelet slovenskih proizvajalcev 2014Peter Prislan, Nike Krajnc, Mitja Piškur, 2014, treatise, preliminary study, study Keywords: kakovost pelet, mehanska obstojnost, vsebnost vode, delež pepela
Published in DiRROS: 12.07.2017; Views: 2696; Downloads: 709
Full text (450,63 KB) |
