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Age, climate and intra-annual density fluctuations in Pinus halepensis in Spain
No full textIntra-annual density fluctuations (IADFs) in tree rings of Aleppo pine (Pinus halepensis) are considered to be among the most promising wood anatomical features in dendrochronological studies. They provide environmental information in addition to those obtained from tree-ring widths. We used a network of 35 sites in Spain, ranging from nearly desert to temperate climate. We analysed tree-ring series of 529 trees to study IADF frequencies, and their dependence on climatic factors and cambial age. The results showed that IADF frequency is age dependent, with its maximum at the cambial age of 27 years (evaluated at breast height). The frequencies varied across the network and at different sites we recorded that 0.3% to 33% of the analysed tree rings contained IADFs. They were more frequent where and when the temperatures were higher, summer drought was intense and autumn was the main precipitation season. IADF formation was particularly related to high minimum temperatures and wet conditions in late summer and autumn. These results suggest that IADF formation is not related to stressful conditions during summer but to favourable conditions during autumn. These conditions promote cambial reactivation and consequently formation of wider tree rings
Project " Diversity of ectomycorrhizal fungi and oligochaeta diversity in Brazil and Slovenia", grant by CNPq, No. 490648/2010-0 process : visit to Brazil of the Dr. Tine Grebenc
Get PDFCuring of commercial phenol-formaldehyde adhesives
Get PDFPhenol-formaldehyde adhesives are in the wood industry most commonly used for bonding of structural wood composites where high strength and durability of the bond line is desired. Their curing is rather complicated due to the reactions that can occur simultaneously. Based on the acidity or alkalinity of added catalyst during the synthesis, these adhesives are divided into novolak and resol type of resins. In the study, the curing of different commercial resol type phenol-formaldehyde adhesives was analysed with differential scanning calorimetry (DSC). The influence of the addition of basic catalyst on the curing of the selected adhesive was examined, and a simulation of time required for the curing of the adhesive at isothermal conditions was also made. It was found that the curing processes of different adhesives varied. Because the examined phenol-formaldehyde adhesives were already optimised during the process of synthesis by means of optimal catalyst addition, the additional amount of catalyst into selected phenol-formaldehyde adhesive was unnecessary and has a negative impact on its curing
Normativ sečnje z motorno žago 2012 - metode dela in osnovne analize : delovno gradivo za 7. sestanek stalne strokovne skupine z pripravo predlogov normativov gozdarskih del
Get PDFPoročilo o spremljanju stanja gozdov za l. 2011 : vsebinsko poročilo o spremljanju stanja gozdov v l. 2011 v skladu s Pravilnikom o varstvu gozdov (2009)
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Molekbase : user friendly system for storing, filtering and converting population molecular data
No full textThe genetic population study of Balkan Silver Fir (Abies alba Mill.)
No full textAbstract
Background and Purpose: Silver fir (Abies alba Mill.) is one of the most
important forest tree species in the Western Balkan area from both economic
and ecological aspect. Its distribution has for years been the subject of
scientific research, the reason being that silver fir from these areas displays
very interesting morphological and genetic differentiation