Template-Type: ReDIF-Article 1.0 Author-Name: Ali Mahdavi Author-Workplace-Name: Department of Forest Sciences, Faculty of Agriculture and Natural Resources, Ilam University, Ilam, Iran Author-Name: Azadeh Maleki Author-Workplace-Name: Department of Forest Sciences, Faculty of Agriculture and Natural Resources, Ilam University, Ilam, Iran Author-Name: Masoud Bazgir Author-Workplace-Name: Department of Soil Sciences, Faculty of Agriculture and Natural Resources, Ilam University, Ilam, Iran Title: Soil properties and carbon sequestration in Persian oak (Quercus brantii var. persica) forests, Iran Abstract: One of the important issues both in the political discussion about climate change and in forest ecosystem research is carbon sequestration. In this paper, we estimated soil carbon sequestration (SCS) in two Persian oak forest stands of different origin (seed and coppice). Soil samples were taken at two soil depths (0-15 and 15-30 cm) and locations (under the tree crown and open area) in each oak stand. Results showed that surface layers (0-15 cm) had the highest soil carbon sequestration ranging from 41.2 t.ha-1 to 47.9 t.ha-1 for both oak forests. The total SCS was higher (between 79.5 and 89.07 t.ha-1) in open areas of the two forest stands than under the crowns of oak trees. Finally, the amount of total SCS in seed originated forest (SOF) (86.52 t.ha-1) was significantly greater (P < 0.05) than in coppice forest (CF) (77.70 t.ha-1). The results indicate that a relatively large proportion of C loss in CF is due to overgrazing, forest degradation and conversion to coppice forests in the study area. Keywords: carbon pool, soil characteristics, coppice forest, Zagros forest Journal: Journal of Forest Science Pages: 247-255 Volume: 65 Issue: 7 Year: 2019 DOI: 10.17221/140/2018-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/140/2018-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201907-0001.txt Handle: RePEc:caa:jnljfs:v:65:y:2019:i:7:id:140-2018-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Vilém Podrázský Author-Name: Martin Baláš Author-Workplace-Name: Department of Silviculture, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: Rostislav Linda Author-Workplace-Name: Department of Silviculture, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: Ota Křivohlavý Author-Workplace-Name: Department of Silviculture, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Title: State of beech pole stands established at the clear-cut and in the underplanting Abstract: European beech (Fagus sylvatica L.) represents the major climax tree species in the forests of Central Europe growing at many sites. The reintroduction of this species is an important silvicultural topic because of stability and diversity of forest ecosystems and vitality of forest soils in this region. The present study documents the growth, quality of growth and vitality of beech plantations in two positions at the same site (580 m a.s.l., forest habitat type 5K8 - acid fir-beech site, soil type Cambisol): underplantings at 50% of the light intensity of open space and clear-cut. Plantations were established in 1994 by bare-root plants on the same day of April, at a 1 × 1 m spacing, the shelter at the underplanted locality was removed in 2010. In 2017, the plantations showed very different characteristics (underplanting/clear-cut position): density 5,900/3,750 trees.ha-1, mean DBH 6.8/7.0, mean height 8.7/6.9 m, basal area 21.41/14.42 m2.ha-1. Underplanting was documented as a very proper way of beech reintroduction into the species composition of Czech forests. The reintroduction of beech at the newly originated clearcuts should be done with the use of ecological shelter of the mature stands. Keywords: European beech, growth, stem quality, silviculture Journal: Journal of Forest Science Pages: 256-262 Volume: 65 Issue: 7 Year: 2019 DOI: 10.17221/59/2019-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/59/2019-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201907-0002.txt Handle: RePEc:caa:jnljfs:v:65:y:2019:i:7:id:59-2019-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Ludmila A. Ivanchina Author-Name: Sergei V. Zalesov Author-Workplace-Name: Department of Forestry, Institute of Forest and Natural Management, Ural State Forest Engineering University, Yekaterinburg, Russia Title: The effect of spruce plantation density on resilience of mixed forests in the Perm Krai Abstract: Over the course of the last few decades, many countries across the globe have experienced mass desiccation of spruce plantations. The subject of our research was the spruce forests of the Russian Perm Krai's mixed forest zone. Spruce is a shade-tolerant tree species and low plantation density may adversely affect the spruce health. The aim of this research is to establish how influential the spruce stand density is on causing desiccation in mixed zones in the Perm Krai. The results of an on-site survey which had recorded spruce desiccation in 2017 were analysed. Within the boundaries of the aforementioned forest areas, 2017 saw the desiccation of spruce trees in 301 forest allotments covering an area of 5,343.7 ha. The value of the weighted average category of spruce forest health in Prikamye varies from 2.7 (severely weakened) to 4.2 (desiccating), and the percentage of the volume of spruce deadwood varies from 17% to 59.5%. When the spruce stand density rises from 0.4 to 0.8, spruce stand resilience to desiccation increases. Keywords: Perm Krai's mixed coniferous-deciduous forest zone, stand density, spruce forest desiccation, spruce forest resilience, weighted average category of health, deadwood volume Journal: Journal of Forest Science Pages: 263-271 Volume: 65 Issue: 7 Year: 2019 DOI: 10.17221/14/2019-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/14/2019-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201907-0003.txt Handle: RePEc:caa:jnljfs:v:65:y:2019:i:7:id:14-2019-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Sajad Ghanbari Author-Workplace-Name: Department of Forestry, Ahar Faculty of Agriculture and Natural Resources, University of Tabriz, Iran Author-Name: Kiomars Sefidi Author-Workplace-Name: Department of of Natural Resources, Faculty of Agriculture and Natural Resources Technology, University of Mohaghegh Ardabili, Ardabil, Iran Author-Name: Matthew M. Aghai Author-Workplace-Name: Center for Sustainable Forestry at Pack Forest, School of Environmental and Forest Science, University of Washington, United States Title: Impact of long and short-term conservation periods on structure of English yew (Taxus baccata L.) in Arasbaran forests, Iran Abstract: Yew (Taxus baccata L.) is one of the most important and threatened tree species in the Arasbaran region of northwestern Iran. To understand the natural stand structure of yew forests to inform forest management, we assessed the structural characteristics and composition of yew communities using the nearest neighbour and full callipering method at three sites with different conservation histories. Within a one-hectare sampling area, tree species identity, diameter, height, and crown diameter were measured. In each of these sampling areas, 56 sample points were surveyed in a 25 m × 25 m grid for tree species identity, diameter, height, and distance from reference to neighbour trees. To quantify the structural characteristics in areas of different conservation status, some indices were calculated including mingling, distance between reference tree and its nearest neighbouring trees, diameter and height differentiation, uniform angle, and Clark-Evans index. Results revealed that four species - hornbeam (68%), maple (8%), yew (7%), and oak (5.2%) - composed 88% of the tree species. The majority of trees had a short distance (2-3 m) between neighbours. The mean diameter differentiation index for long-term and short-term conservation areas was 0.59 and 0.06, respectively. The uniform angle index showed that there was no class value = "1" at all three sites. In the long-term enclosed area, Clark-Evans index was 1.18. In short-term enclosed areas, it was less than 1 (0.82). At all sites, yew trees were in the least vital class. We conclude that enclosing affects the yew stand structure, specifically in long-term periods of enclosure. Keywords: conservation-based management, diameter differentiation, forest structure, nearest neighbour Journal: Journal of Forest Science Pages: 272-282 Volume: 65 Issue: 7 Year: 2019 DOI: 10.17221/45/2019-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/45/2019-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201907-0004.txt Handle: RePEc:caa:jnljfs:v:65:y:2019:i:7:id:45-2019-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Ali Akbar Mohammad Ali Pourmalekshah Author-Name: Mohamad Hadi Moayeri Author-Workplace-Name: Department of Forestry, Faculty of Forest Science, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran Author-Name: Aidin Parsakhoo Author-Workplace-Name: Department of Forestry, Faculty of Forest Science, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran Title: Effect of the root biotechnical characteristics of Alnus subcordata, Paulownia fortunei and Populus deltoides on the soil mechanics Abstract: The effect of root reinforcement depends on the biotechnical characteristics of the root system including the tensile strength of individual roots, the root density and the distribution of the root system in the soil. This research was conducted in the Hyrcanian forest in Iran, where shallow landslides are frequent due to road construction. The effect of the root biotechnical characteristics of Alnus subcordata, Paulownia fortunei and Populus deltoides each one in 2-, 10- and 15-year-old plantations was assessed. The profile trenching method was used in this study to obtain the root area ratio of individual species by counting the number of roots and measuring the root diameter. For each species, single root specimens were sampled and tested for tensile tests in the laboratory using the standard Instron apparatus. The natural moisture content (two weeks after rainfall), Atterberg limits, shear strength of the soil were determined for plantations, stable and unstable sites. Results of this study indicated that plastic index and internal friction angle decreased with increasing root diameter rate. Moreover, internal friction angle and cohesion increased with increasing root area ratio and root diameter and density index. Tensile strength of roots decreased with increasing stand age. The highest and the lowest tensile strengths among species were observed for Paulownia fortunei and Populus deltoides, respectively. The findings of this research contribute to expanding the knowledge of root biotechnical properties of some tree species and to the choice of the most appropriate species for improving plastic index and shear strength in landslide prone areas. Keywords: tensile strength, shear strength, Atterberg limits, root density, slope stabilization Journal: Journal of Forest Science Pages: 283-290 Volume: 65 Issue: 7 Year: 2019 DOI: 10.17221/55/2019-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/55/2019-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201907-0005.txt Handle: RePEc:caa:jnljfs:v:65:y:2019:i:7:id:55-2019-JFS