Template-Type: ReDIF-Article 1.0 Author-Name: I. Marková Author-Workplace-Name: Faculty of Forestry and Wood Technology, Mendel University of Agriculture and Forestry in Brno, Brno, Czech Republic Author-Name: I. Drápelová Author-Workplace-Name: Faculty of Forestry and Wood Technology, Mendel University of Agriculture and Forestry in Brno, Brno, Czech Republic Author-Name: S. Truparová Author-Workplace-Name: Faculty of Forestry and Wood Technology, Mendel University of Agriculture and Forestry in Brno, Brno, Czech Republic Title: Comparison of deposition fluxes on the open area and in mountain spruce stands of different density Abstract: To better understand the chemical transformation of rainfall after the passage through the canopies it is necessary to study throughfall deposition fluxes within forest stands. The comparison of bulk deposition fluxes of Ca, Mg, K, S-SO4, N-NO3 and N-NH4 in mountain spruce stands of different stand density and bulk deposition fluxes on the open area was made at the study site Bílý Kříž (Moravian-Silesian Beskids Mts., Czech Republic) during the period of 1999-2006. A linear relationship between the amount of rainfall on the open area and the amount of throughfall in the spruce stand was found. Throughfall deposition fluxes of selected elements in the dense as well as in the sparse spruce stands were higher when compared with bulk deposition fluxes on the open area. There were mostly statistical significant differences between the bulk deposition fluxes on the open area and those in the studied spruce stands. The throughfall deposition fluxes of Ca, Mg, K and S-SO4 were influenced by the spruce stand density. Keywords: throughfall, Norway spruce, Moravian-Silesian Beskids Mts., Czech Republic Journal: Journal of Forest Science Pages: 395-402 Volume: 55 Issue: 9 Year: 2009 DOI: 10.17221/37/2009-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/37/2009-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-200909-0001.txt Handle: RePEc:caa:jnljfs:v:55:y:2009:i:9:id:37-2009-JFS Template-Type: ReDIF-Article 1.0 Author-Name: K. Skrzyszewska Author-Workplace-Name: Department of Forest Trees Breeding, Faculty of Forestry, Agricultural University of Cracow, Cracow, Poland Author-Name: J. Chłanda Author-Workplace-Name: Department of Forest Trees Breeding, Faculty of Forestry, Agricultural University of Cracow, Cracow, Poland Title: A study on the variation of morphological characteristics of silver fir (Abies alba Mill.) seeds and their internal structure determined by X-ray radiography in the Beskid Sądecki and Beskid Niski mountain ranges of the Carpathians (southern Poland) Abstract: The variation of the morphological characteristics and internal structure of silver fir (Abies alba Mill.) seeds from 4 stands growing at the altitude of 625-750 m in the Beskid Sądecki and Beskid Niski mountain ranges of the Carpathians in southern Poland was estimated. Seeds were collected in the second half of September 2004. The weight of 1,000 air-dry seeds was determined and their viability was estimated with the use of X-ray radiography. The length and width of the embryo, endosperm and embryo cavity were measured on X-ray photographs. The morphological seed characteristics, i.e. length, width, volume, surface area, and wing colour (light-brown, brown, dark-brown, and cherry-red) were also included in the analysis. The statistically significant effect of the provenance on the parameters of the embryo, endosperm and embryo cavity as well as on the occurrence of full and insect-attacked seeds was found. The weight of 1,000 seeds was below 55 g which is considered to be a long-term mean for silver fir in Poland. It was positively correlated with the length and width of the embryo, endosperm and embryo cavity as well as with the degree of filling of the embryo cavity with the embryo. The weight of seeds was also positively correlated with their length, width and surface area. It was found that the wing colour was correlated with the weight of 1,000 seeds as well as with the proportion of insect-attacked and empty seeds. The proportion of seeds with brown wings was negatively correlated with the weight of 1,000 seeds and numbers of full seeds, while it was positively correlated with numbers of seeds infested by insects and empty seeds. The occurrence of light-brown and cherry-red wings was associated with a high proportion of full seeds. The results of the correlation between seed parameters and selected characteristics of test trees indicated statistically significant relationships. A positive correlation was found between the proportion of full seeds and the height, crown shape, dbh, and bark thickness of trees while the correlation between these tree characteristics and the proportion of insect-attacked seeds was negative. Keywords: Abies alba, X-ray, seed viability, internal seed structure, seed morphological characteristics, Carpathians Journal: Journal of Forest Science Pages: 403-414 Volume: 55 Issue: 9 Year: 2009 DOI: 10.17221/48/2008-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/48/2008-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-200909-0002.txt Handle: RePEc:caa:jnljfs:v:55:y:2009:i:9:id:48-2008-JFS Template-Type: ReDIF-Article 1.0 Author-Name: V. Gryc Author-Workplace-Name: Faculty of Forestry and Wood Technology, Mendel University of Agriculture and Forestry in Brno, Brno, Czech Republic Author-Name: H. Vavrčík Author-Workplace-Name: Faculty of Forestry and Wood Technology, Mendel University of Agriculture and Forestry in Brno, Brno, Czech Republic Title: Variability of spruce (Picea abies [L.] Karst.) compression strength with present reaction wood Abstract: The aim of research was to find out the variability of spruce (Picea abies [L.]) Karst.) wood compression strength limits in the direction parallel to grain. The wood strength was examined using samples from a tree with present reaction (compression) wood. The strength was found out for individual stem zones (CW, OW, SWL and SWR). The zone with present compression wood (CW) demonstrated slightly higher values of wood strength limits. The differences in the limits of compression strength parallel to grain in individual zones were not statistically significant. All the data acquired by measuring were used to create 3D models for each zone. The models describe the strength along the radius and along the stem height. The change of strength along the stem radius was statistically highly significant. There was an obvious tendency towards an increase in the strength limit in the first 40 years. With the increased stem height, there is a slight decrease in wood strength. Keywords: strength parallel to grain, spruce, compression wood, reaction wood Journal: Journal of Forest Science Pages: 415-422 Volume: 55 Issue: 9 Year: 2009 DOI: 10.17221/13/2009-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/13/2009-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-200909-0003.txt Handle: RePEc:caa:jnljfs:v:55:y:2009:i:9:id:13-2009-JFS Template-Type: ReDIF-Article 1.0 Author-Name: M. R. Ghaffarian Author-Workplace-Name: Department of Forest and Soil Sciences, Institute of Forest Engineering, University of Natural Resources and Applied Life Sciences, Vienna, Austria Author-Name: K. Stampfer Author-Workplace-Name: Department of Forest and Soil Sciences, Institute of Forest Engineering, University of Natural Resources and Applied Life Sciences, Vienna, Austria Author-Name: J. Sessions Author-Workplace-Name: Department of Forest Engineering, College of Forestry, Oregon State University, Corvallis, USA Title: Comparison of three methods to determine optimal road spacing for forwarder-type logging operations Abstract: Optimum road spacing (ORS) of forwarding operation in Styria in Southern Austria is studied in this paper. In a harvesting operation it is important to compute the ORS to minimize the total cost of harvesting and roading. The aim of this study was a comparison of different methods to study ORS. Data from 82 cycles were used to develop two models for predicting the cycle time using statistical analysis of a time study data base. The ORS was computed by three methods including Matthews' formula (1942), Sundberg's method (1976), and the two statistical models for predicting the cycle time. The results gave the ORS for one-way forwarding using Matthew's formula as 1,969 m, Sund-berg's model as 394.4 m, and the two time study models as 463 and 909 m. The analysis of forwarding data indicated that the speed was related to a distance which contributed to the difference between models and that the loading and unloading time may be related to one or several other study variables. Keywords: forwarding, production, cost, travelling model, optimum road spacing Journal: Journal of Forest Science Pages: 423-431 Volume: 55 Issue: 9 Year: 2009 DOI: 10.17221/79/2008-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/79/2008-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-200909-0004.txt Handle: RePEc:caa:jnljfs:v:55:y:2009:i:9:id:79-2008-JFS Template-Type: ReDIF-Article 1.0 Author-Name: K. L. O'Hara Author-Workplace-Name: University of California, Berkeley, USA Title: Multiaged silviculture in North America Abstract: Multiaged silviculture is highly variable across North America but a commonality is the ties to the negative exponential diameter distribution to guide stocking control. These methods have evolved in several regions to include alternative stand structures and new stocking control tools are being developed. A trend in these new developments is integrating disturbance regimes and their effects on stand structure. The result, in some cases, is a movement towards longer cutting cycles and more flexible guidelines for stand structure. Keywords: multiaged silviculture, North America, diameter distribution, stocking control Journal: Journal of Forest Science Pages: 432-436 Volume: 55 Issue: 9 Year: 2009 DOI: 10.17221/4/2009-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/4/2009-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-200909-0005.txt Handle: RePEc:caa:jnljfs:v:55:y:2009:i:9:id:4-2009-JFS