Measured temperature and moisture profiles during thermal modification of beech (Fagus sylvatica L.) and spruce (Picea abies L. Karst.) wood

Holzforschung ◽  
2014 ◽  
Vol 68 (2) ◽  
pp. 175-183 ◽  
Author(s):  
Petr Čermák ◽  
Petr Horáček ◽  
Peter Rademacher
Keyword(s):  
Picea Abies ◽  
Fagus Sylvatica ◽  
Soret Effect ◽  
Exothermic Reaction ◽  
Longitudinal Direction ◽  
Thermal Modification ◽  
Measured Temperature ◽  
Moisture Movement ◽  
Chamber Temperature ◽  
Moisture Profiles

Abstract The temperature and moisture profiles during thermal modification of beech (Fagus sylvatica L.) and spruce (Picea abies L. Karst.) wood have been investigated. Specimens with dimensions of 80×80×200 mm3 were heat treated based on ThermoWood technology. Heat transfer was continuously measured by several thermocouples placed into various positions of the samples. In the course of the treatment, samples were removed from the chamber at different times, and their moisture content (MC) was measured by the so-called slicing technique. The complete data of heat and moisture movement during the heat treatment process are presented. Significant temperature gradients occur in the initial and modification stages of the process. In the latter, the chamber temperature was 200°C for 3 h, but exothermic reaction increased the sample temperatures to 240°C (beech) and 215°C (spruce). Thermodiffusion (Soret effect) at the beginning of the process was observed. Therefore, the MC under surfaces (in transverse and in longitudinal direction) was increasing ∼0.5%–3% for 5 h. The results provide a better insight into details of thermal modification of wood.

Temperature and Moisture Distributions in a Clay Buffer Material Due to Thermal Gradients

1992 ◽  
Vol 294 ◽  
Author(s):  
A.M.O. Mohamed ◽  
R.N. Yong ◽  
B. Kjartanson
Keyword(s):  
Temperature Gradients ◽  
Thermal Gradients ◽  
Measured Temperature ◽  
Moisture Movement ◽  
Equilibrium Time ◽  
One Dimensional ◽  
Diffusion Parameters ◽  
Buffer Material ◽  
Heat And Moisture ◽  
Moisture Profiles

ABSTRACTSeveral series of one-dimensional tests were used to investigate the nature of transient heat and moisture movements in a clay buffer under different imposed temperature gradients. The measured temperature and moisture profiles were used to calculate the diffusion parameters governing heat and moisture movement in the buffer material. The diffusion parameters are shown to depend on the moisture content, temperature and moisture equilibrium time.

scholarly journals Utilization of spruce (Picea abies [L.] Karst.) and beech (Fagus sylvatica L.) wood in plywood production using different processing pressures

2014 ◽  
Vol 60 (No. 12) ◽  
pp. 495-499
Author(s):  
P. Král ◽  
P. Klímek
Keyword(s):  
Picea Abies ◽  
Fagus Sylvatica ◽  
Longitudinal Direction ◽  
The Other ◽  
Levels Of Processing ◽  
Bending Properties ◽  
Laboratory Conditions ◽  
Fagus Sylvatica L ◽  
The Common ◽  
Better Than

In this research the spruce plywood board and combined spruce-beech plywood board were prepared in laboratory conditions using two levels of processing pressure. The bending properties in perpendicular and longitudinal direction were measured and compressibility and density were specified. Considering the obtained results, there was found an overall increase of the bending properties in spruce plywood manufactured by the higher pressure and a decline of properties perpendicular to the grain in combined spruce-beech plywood board. On the other hand, combined spruce-beech plywood boards produced by the common processing pressure performed better than both types of spruce plywood.  

Nutrient fluxes in pure and mixed stands of spruce (Picea abies) and beech (Fagus sylvatica)

2009 ◽  
Vol 322 (1-2) ◽  
pp. 317-342 ◽  
Author(s):  
Torsten W. Berger ◽  
Hubert Untersteiner ◽  
Martin Toplitzer ◽  
Christian Neubauer
Keyword(s):  
Picea Abies ◽  
Fagus Sylvatica ◽  
Nutrient Fluxes ◽  
Mixed Stands

scholarly journals Patterns of laccase and peroxidases in coarse woody debris of Fagus sylvatica, Picea abies and Pinus sylvestris and their relation to different wood parameters

2015 ◽  
Vol 135 (1) ◽  
pp. 109-124 ◽  
Author(s):  
Tobias Arnstadt ◽  
Björn Hoppe ◽  
Tiemo Kahl ◽  
Harald Kellner ◽  
Dirk Krüger ◽  
...  
Keyword(s):  
Picea Abies ◽  
Pinus Sylvestris ◽  
Fagus Sylvatica ◽  
Coarse Woody Debris ◽  
Woody Debris

scholarly journals The structure of forest stands in the Tatra National Park: The results of 2016–2017 inventory

2019 ◽  
Vol 80 (1) ◽  
pp. 13-21 ◽  
Author(s):  
Jan Bodziarczyk ◽  
Jerzy Szwagrzyk ◽  
Tomasz Zwijacz-Kozica ◽  
Antoni Zięba ◽  
Janusz Szewczyk ◽  
...  
Keyword(s):  
Picea Abies ◽  
Fagus Sylvatica ◽  
National Park ◽  
Forest Stands ◽  
Protection Zone ◽  
Dead Trees ◽  
Standing Dead ◽  
Elevation Zone ◽  
Standing Dead Trees ◽  
Tatra National Park

Abstract The composition and structure of forest stands in the Tatra National Park were examined using data gathered in 2016 and 2017 from 617 circular sample plots (0.05 ha each). The diameter at breast height of all living trees, standing dead trees, snags, and wind throws was measured along with diameters and lengths of fallen logs within the plot boundaries. Tree height was measured for all living trees within the core (0.01 ha) of the sample plots. Using the obtained data, height-diameter curves were calculated for all major tree species and in the case of spruce, the height-diameter relationships were also calculated separately for each of the three elevation zones (up to 1200 m, between 1200 and 1400 m, above 1400 m). For each elevation zone and park protection zone, we also determined the volumes of live and dead trees. The volume of living trees in the Tatra National Park amounted to 259 m3/ha, which was higher than the volume of dead trees (176 m3/ha). Snags constituted the largest part of the dead wood whilst over 97% of the standing dead trees were spruce Picea abies. Among living trees, the share of spruce ranged from 81% in the low elevation zone to 98% in the middle zone. Other significant species in the lower zone were Abies alba (11%) and Fagus sylvatica (4.5%), while in the middle and upper elevation zones only Sorbus aucuparia occurred in significant numbers. Furthermore, in the lower elevation zone, Fagus sylvatica was the only species displaying significantly higher volumes in the ‘strict protection’ zone compared to the other park areas. In the ‘landscape protection’ zone, Picea abies was the most dominant species and the share of other species in the lowest elevation zones calculated based on tree density was smaller than calculated based on tree volume, indicating problems with stand conversion from spruce monoculture to mixed forest.

scholarly journals Differences in fine root traits between Norway spruce (Picea abies [L.] Karst.) and European beech (Fagus sylvatica L.) – A case study in the Kysucké Beskydy Mts

2009 ◽  
Vol 55 (No. 12) ◽  
pp. 556-566 ◽  
Author(s):  
B. Konôpka
Keyword(s):  
Picea Abies ◽  
Norway Spruce ◽  
Fagus Sylvatica ◽  
Seasonal Dynamics ◽  
Fine Roots ◽  
Fine Root ◽  
Root Traits ◽  
European Beech ◽  
Root Turnover ◽  
Mortality Ratio

Interspecific comparisons of the fine root “behaviour” under stressful situations may answer questions related to resistance to changing environmental conditions in the particular tree species. Our study was focused on Norway spruce (<I>Picea abies</I> [L.] Karst.) and European beech (<I>Fagus sylvatica</I> L.) grown in an acidic soil where acidity was caused by past air pollution in the Kysucké Beskydy Mts., North-Western Slovakia. Between April and October 2006, the following fine root traits were studied: biomass and necromass seasonal dynamics, vertical distribution, production, mortality, fine root turnover and production to mortality ratio. Sequential soil coring was repeatedly implemented in April, June, July, September, and October including the soil layers of 0–5, 5–15, 15–25, and 25–35 cm. Results indicated that spruce had a lower standing stock of fine roots than beech, and fine roots of spruce were more superficially distributed than those of beech. Furthermore, we estimated higher seasonal dynamics and also higher turnover of fine roots in spruce than in beech. The production to mortality ratio was higher in beech than in spruce, which was hypothetically explained as the effect of drought episodes that occurred in July and August. The results suggested that the beech root system could resist a physiological stress better than that of spruce. This conclusion was supported by different vertical distributions of fine roots in spruce and beech stands.

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