|
Anotace:
|
článek ve sborníku z mezinárodní konference - InWood2015: Innovations in Wood Materials and Processes The natural durability tests were carried out using the European standards EN 350-1 and EN 113. Three species of wood-decay fungi were used to test natural durability, two brown-rot fungi: Poria placenta (Fr.) Cooke and Laetiporus sulphureus (Bull.) Murrill , and one white rot fungus Trametes versicolor (L.) Lloyd. Fungi were inoculated in malt agar medium in Kolle flasks under sterile conditions. After complete covering of medium surface the sterilized samples were put into flasks. As a reference samples the wood of beech (T. versicolor and L. sulphureus) and pine sapwood (P. placenta) were used. Ten samples from each set were exposed to fungi degradation for 16 weeks, at a temperature of 22 °C and 65% air humidity. Finally, they were dried at 103 °C, mass los was determined gravimetrically. Three subfossile oak trunks of different ages were found in the bank of the Bečva River, near Osek nad Bečvou. All trunks were dated by radiocarbon dating and also dedrochonologically. The individual trunks come from these periods: A - after year 1018; B - 208 BC - 137 AD; C - 1131-804 BC.
|