Template-Type: ReDIF-Article 1.0 Author-Name: J. Trochta Author-Workplace-Name: Department of Forest Ecology, Silva Tarouca Research Institute for Landscape and Ornamental Gardening, Brno, Czech Republic Author-Workplace-Name: Department of Geoinformation Technologies, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Author-Name: K. Král Author-Workplace-Name: Department of Forest Ecology, Silva Tarouca Research Institute for Landscape and Ornamental Gardening, Brno, Czech Republic Author-Name: P. Šamonil Author-Workplace-Name: Department of Forest Ecology, Silva Tarouca Research Institute for Landscape and Ornamental Gardening, Brno, Czech Republic Title: Effects of wildfire on a pine stand in the Bohemian Switzerland National Park Abstract: The pine stand in the Havraní Skála locality in the Bohemian Switzerland National Park was affected by an extensive mixed-severity wildfire in summer 2006. The fire severity, fire type and fire extent were assessed by various fire severity measures collected in the field (mean bole char height on stems on sample plots, content of oxidizable C and total N at a soil depth of 0-5 cm), as well as by classification and filtering of green canopy cover from time series of aerial photographs acquired before the fire (2005), soon after the fire (2006) and one year after the fire (2007). The specific image analyses made it possible to uncover the spatial and temporal pattern of the stand defoliation. The central part of the site was mainly affected by the crown fire and thus defoliated substantially right during the fire. On the contrary, the peripheral part of the site was mostly affected by low-severity ground fire and therefore defoliated progressively one year later. All the fire severity measures used were well related. Keywords: forest fire, aerial photographs, classification, defoliation, fire severity Journal: Journal of Forest Science Pages: 299-307 Volume: 58 Issue: 7 Year: 2012 DOI: 10.17221/68/2011-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/68/2011-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201207-0001.txt Handle: RePEc:caa:jnljfs:v:58:y:2012:i:7:id:68-2011-JFS Template-Type: ReDIF-Article 1.0 Author-Name: S. Małek Author-Workplace-Name: Department of Forest Ecology, Faculty of Forestry, University of Agriculture in Krakow, Krakow, Poland Author-Name: K. Krakowian Author-Workplace-Name: Department of Forest Ecology, Faculty of Forestry, University of Agriculture in Krakow, Krakow, Poland Title: The effect of deforestation on spring water chemistry on Skrzyczne (Silesian Beskid Mountains, Poland) Abstract: The Norway spruce dieback which occurred in the Western Carpathians is of interest to scientists in many fields. The goal of this research was to determine its effect on spring water chemistry. Due to environmental factors such as: high precipitation - up to 1,400 mm.year-1 while the average for Poland is 600 mm.year-1; kind of bedrock (the area is built of Godula Sandstone) which causes shallow water circulation so that springs are considered as shallow supplied, it was expected that the plant cover changes might affect spring water chemistry. Such observations were partially confirmed by Astel et al. (2008), when differences between types of forest stands were found. Those results showed that the presence of mixed stands caused an increase in pH values and an increase in calcium and magnesium concentrations compared to the spring waters of Norway spruce monocultures growing on the same geological bedrock. Currently another point of view was a possibility to analyse what was before and after deforestation.The research was carried out in 2004 and 2009 in two catchments on Skrzyczne in the Silesian Beskid Mountains. The research did not show any statistically significant differences in water chemistry with one exception: pH in June 2009 was higher (average of 0.61) in springs without plant cover change than in the second group. This might be an effect of more water flowing through the more acid soil horizons with higher concentration of humic acids on the deforested area, where large amounts of organic matter were left. It is possible that changes will be observed in the years to come so that further monitoring should take place. Keywords: pH, mountain springs, snowmelt, rainfall, forest and water interaction Journal: Journal of Forest Science Pages: 308-313 Volume: 58 Issue: 7 Year: 2012 DOI: 10.17221/77/2011-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/77/2011-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201207-0002.txt Handle: RePEc:caa:jnljfs:v:58:y:2012:i:7:id:77-2011-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Ch.D.B. Hawkins Author-Workplace-Name: Mixedwood Ecology and Management Program, University of Northern British Columbia, Prince George, Canada Author-Workplace-Name: Yukon College, Yukon Research Centre, Whitehorse, Canada Author-Name: A. Dhar Author-Workplace-Name: Mixedwood Ecology and Management Program, University of Northern British Columbia, Prince George, Canada Author-Name: B.J. Rogers Author-Workplace-Name: Mixedwood Ecology and Management Program, University of Northern British Columbia, Prince George, Canada Author-Workplace-Name: Ministry of Forests and Range of British Columbia, Prince George, Canada Title: How much birch (Betula papyrifera) is too much for maximizing spruce (Picea glauca) growth: a case study in boreal spruce plantation forests Abstract: Interest in conifer-broadleaf mixedwood forests has greatly increased due to continuous demand for hardwood products and a shift towards more biological or ecosystem-based management. In British Columbia, more than 30% of the productive forest land is a conifer-broadleaf mixture and current forest regulations are more conifer biased rather than maintaining a mixed-species condition. The aim of this study was to examine the impact of paper birch on white spruce growth. Spruce growth data from 10 to 18 years old complex stands indicate that radial, height, and stem volume was not impacted by retaining up to 3,000 stems.ha-1 of birch. Similarly, growth and yield model projections suggest spruce-birch stands would be more productive up to a threshold birch density (3,000 stems.ha-1) than pure spruce stands. At a 4% real interest rate, the removal of birch from these stands does not appear to be warranted as an investment. The results suggest that instead of encouraging uniform broadleaf removal across conifer plantations, mixed species management strategies could enhance the forest productivity, stand diversity and resilience. Keywords: competition, future value, growth and yield model, forest management, productivity Journal: Journal of Forest Science Pages: 314-327 Volume: 58 Issue: 7 Year: 2012 DOI: 10.17221/8/2012-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/8/2012-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201207-0003.txt Handle: RePEc:caa:jnljfs:v:58:y:2012:i:7:id:8-2012-JFS Template-Type: ReDIF-Article 1.0 Author-Name: K. Černý Author-Workplace-Name: Department of Biological Risks, Silva Tarouca Research Institute for Landscape and Ornamental Gardening, Průhonice, Czech Republic Author-Workplace-Name: Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Prague, Czech Republic Author-Name: V. Strnadová Author-Workplace-Name: Department of Biological Risks, Silva Tarouca Research Institute for Landscape and Ornamental Gardening, Průhonice, Czech Republic Title: Winter survival of Phytophthora alni subsp. alni in aerial tissues of black alder Abstract: The winter survival of the invasive pathogen Phytophthora alni subsp. alni in black alder stems was studied in the bankside alder stand of the Moravská Dyje River in southern Bohemia after two very different winter seasons: cold in 2008/2009, with the average temperature of -1.96°C, and extremely mild in 2006/2007, with the average temperature of 2.54°C. The difference in these two winters resembles the expected potential climate change in Central Europe in this century. After the cold winter of 2008/2009, the pathogen survived in only 13.91% of the samples, with the average survival rate of 2.70%. The pathogen survived the mild winter much better and was successfully isolated from 86.09% of the samples, with the average survival rate of 25.52%. Moreover, the total thickness of the covering tissues (outer + inner bark) and exposure to the most heated southwestern quadrant of stem girth positively affected the pathogen survival. Winter freezing seems to be an important environmental factor regulating the pathogen survival in alder stems and disease severity. Keywords: Phytophthora alni, winter survival, black alder, temperature, Phytophthora alder disease Journal: Journal of Forest Science Pages: 328-336 Volume: 58 Issue: 7 Year: 2012 DOI: 10.17221/11/2012-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/11/2012-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201207-0004.txt Handle: RePEc:caa:jnljfs:v:58:y:2012:i:7:id:11-2012-JFS