Template-Type: ReDIF-Article 1.0 Author-Name: M. Lotfalian Author-Workplace-Name: Department of Forestry, Faculty of Natural Resources, Sari Agricultural Sciences and Natural Resources University, Sari, Iran Author-Name: E. H. Zadeh Author-Workplace-Name: Department of Forestry, Faculty of Natural Resources, Sari Agricultural Sciences and Natural Resources University, Sari, Iran Author-Name: S. A. Hosseini Author-Workplace-Name: Faculty of Natural Resources, Mazandaran University, Sari, Iran Title: Calculating the correction factor of skidding distance based on forest road network Abstract: Average skidding distance for forest stands is an important parameter for the determination of the optimum road density and spacing. In this research the real mean skidding distance and theoretical mean skidding distance were measured to calculate the correction factor of skidding distance for Chafrood forest in Hyrcanian zone. The length and azimuth of skid trails from road and depot junction to forest interior were measured. Moreover, the position of skid trail was recorded by GPS. These skid trails with a buffer of 140 m were designed on a topographical map using Arc GIS software. Results indicated that the road spacing of 500 m in the study area resulted in a theoretical mean skidding distance of 125 m. For a real mean skidding distance of 525.9 m and for the mean slope of 40%, the correction factor was estimated to be 4.2. Keywords: real skidding distance, theoretical skidding distance, correction factor, Chafrood forest Journal: Journal of Forest Science Pages: 467-471 Volume: 57 Issue: 11 Year: 2011 DOI: 10.17221/1/2011-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/1/2011-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201111-0001.txt Handle: RePEc:caa:jnljfs:v:57:y:2011:i:11:id:1-2011-JFS Template-Type: ReDIF-Article 1.0 Author-Name: M. Turčáni Author-Workplace-Name: Department of Forest Protection and Game Management , Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: J. Patočka Title: Does intraguild predation of Cosmia trapezina L. (Lep.: Noctuidae) influence the abundance of other Lepidoptera forest pests? Abstract: The noctuid C. trapezina (CT) has been considered an occasional predator of other Lepidoptera larvae. Functional/numerical response of predator and/or prey was estimated using 27 years of time-series data from Slovakia and stepwise multiple regression models (SMRM). SMRM were used to examine a possible delayed density-dependent feedback. We constructed 12 order-three autoregressive models [AR(3)] for CT and candidate prey. Independent variables were abundance of C. trapezina and abundance of candidate prey in lags 1, 2, and 3. Model variants were: (1) predation on free feeder models (FFM); (2) predation on shelter feeder models (SFM); (3) predation on the sum of 8 species models (S8M); (4) predation on all Lepidoptera models (ALM). Models were constructed for three areas (created by grouping sites based on significant correlations among CT populations). Additional comparative models were constructed for another three noctuid species and one geometrid species to compare their regression parameters under the same conditions as for CT. In total, 48 AR(3) SMRM were constructed for comparative species. A negative response of shelter feeders was found in models mainly for CT. We also found the positive response of CT growth rate to abundance of shelter feeders in lag 3 on two out of three models. This pattern was not found for any other comparison of species in the analysis. Possible mechanisms for these results are discussed. Keywords: Cosmia trapezina, intraguild predation, Lepidoptera larvae, time series Journal: Journal of Forest Science Pages: 472-482 Volume: 57 Issue: 11 Year: 2011 DOI: 10.17221/99/2010-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/99/2010-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201111-0002.txt Handle: RePEc:caa:jnljfs:v:57:y:2011:i:11:id:99-2010-JFS Template-Type: ReDIF-Article 1.0 Author-Name: R.P. Gunaga Author-Workplace-Name: College of Forestry, Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, Dapoli, Ratnagiri (Dist.), Maharashtra, India Author-Name: A.H. Kanfade Author-Workplace-Name: Conservator of Forest (Social Forestry), Agartala, India Author-Name: R. Vasudeva Author-Workplace-Name: College of Forestry, Sirsi, Karnataka, South India Title: Soil fertility status of 20 seed production areas of Tectona grandis Linn. f. in Karnataka, India Abstract: The seed production area (SPA) is an improved plantation managed for production of quality seeds for a large-scale plantation programme. The soil nutrient is one of several factors affecting seed production among SPAs. The status of soil nutrients and their effect on seed production are poorly understood. Hence, the present study was undertaken in 20 seed production areas located in different seed zones of Karnataka, South India. Results showed that there was a greater variation among SPAs in various soil properties like soil pH, organic carbon, available NPK (nitrogen, phosphorus and potassium). Some of the studied parameters recorded significant variations among three different depths: 0-20 (top), 20-40 (middle) and 40-60 cm (bottom). For instance, organic carbon and available potassium showed significant variations at different depths, where the highest content was recorded in the top layer, followed by middle and bottom layers. Considering associations between soil properties and tree growth, organic carbon was positively associated with dbh (diameter at breast height; r = 0.500), stem roundness (r = 0.351) and stem volume (r = 0.250). Similarly, available nitrogen positively influenced the stem volume (r = 0.250). Though the fruit yield varied among SPAs, none of the studied soil parameters showed a significant influence on fruit yield indicating that some other factors like genetic ones, phenology, rainfall overlapping with peak flowering might control it. Data on site quality showed that all existing SPAs studied were growing in poor site conditions, however, this could be one of the factors affecting overall seed yield among SPAs. Hence, it is recommended to undertake a few important silvicultural interventions like application of fertilizer/organic manure, soil working, spraying of floral hormone and others to improve the existing seed production level. Keywords: soil properties, seed production area, fruit production Journal: Journal of Forest Science Pages: 483-490 Volume: 57 Issue: 11 Year: 2011 DOI: 10.17221/119/2010-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/119/2010-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201111-0003.txt Handle: RePEc:caa:jnljfs:v:57:y:2011:i:11:id:119-2010-JFS Template-Type: ReDIF-Article 1.0 Author-Name: M. Bošeľa Author-Workplace-Name: National Forest Centre - Forest Research Institute in Zvolen, Zvolen, Slovakia Author-Workplace-Name: Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: L. Kulla Author-Workplace-Name: National Forest Centre - Forest Research Institute in Zvolen, Zvolen, Slovakia Author-Name: R. Marušák Author-Workplace-Name: Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Detrending ability of several regression equations in tree-ring research: a case study based on tree-ring data of Norway spruce (Picea abies [L.]) Abstract: The aim of this study was to investigate tree-ring width variability and to distinguish groups of trees with similar growth trends in order to study tree growth responses to various stand and site conditions. The methods of cluster analysis were employed for this purpose. Four distinct groups of trees were identified. For each group, the mean tree-ring curve was calculated in order to look for the main signals that distinguish the groups from one another. The idea behind this was to divide the samples into homogeneous groups with similar growth trends, representing typical examples of variability of the studied Norway spruce population. In the next step, several regression functions were studied and compared for their ability to fit the ring-width-age data applied to the mean ring-width curve of each group. Fischer's F-test was used to test the differences in goodness of fit between the equations in each group. From all examined/applied equations, smoothing spline, polynomial of degree 5, and Šmelko-Burgan functions were found to be the most universal and suitable for detrending of all examined ring width curves. Hugershoff function was found to be suitable for curves with one local maximum only. Exponential and Korf's functions were unsatisfactory for the purposes of tree ring curves detrending. Keywords: radial increment, growth functions, empirical fitting, tree-ring indices, dendroclimatology Journal: Journal of Forest Science Pages: 491-499 Volume: 57 Issue: 11 Year: 2011 DOI: 10.17221/134/2010-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/134/2010-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201111-0004.txt Handle: RePEc:caa:jnljfs:v:57:y:2011:i:11:id:134-2010-JFS Template-Type: ReDIF-Article 1.0 Author-Name: V. Pešková Author-Workplace-Name: Forestry and Game Management Research Institute, Jíloviště-Strnady, Czech Republic Author-Name: J. Landa Author-Workplace-Name: Prague, Czech Republic Author-Name: F. Soukup Author-Workplace-Name: Forestry and Game Management Research Institute, Jíloviště-Strnady, Czech Republic Title: Findings regarding ectotrophic stability of Norway spruce forest of the Krkonoše and Orlické Mountains based on mycorrhiza studies Abstract: Analyses of root mycorrhizal samples and monitoring of fruiting bodies of macromycetes from Norway spruce stands at mountain and foothill localities in the Krkonoše and Orlické Mts. provided several data series allowing to assess and compare (albeit somewhat preliminarily) mycorrhizal conditions and macromycete incidence related to stand ages and location conditions. The overall mycorrhizal conditions in young (10 years old) and older (80 years old) stands on formerly agricultural soils are comparable to those in 80- and 90-year-old forests growing on standard forest soils, but young spruce stands in the Orlické Mts. replanted on forest soils do not surprisingly show any favourable mycorrhizal characteristics. The research documents a marked diversity of macromycete species composition in mountain spruce stands compared to foothill spruce stands on former agricultural soils. While in the younger mountain spruce stands of the Orlické Mts. the expansion of macromycete species composition began to develop in a similar fashion to that in the Krkonoše Mts., the comparison of older (80-year-old) stands on formerly agricultural soils in the Orlické Mts. foothills and Krkonoše Mts. implies that the macromycete species composition developed quite differently but with a similar success. Keywords: forest ectotrophic stability, species spectrum of macromycetes, mycorrhizae, root, defoliation, Picea abies Journal: Journal of Forest Science Pages: 500-513 Volume: 57 Issue: 11 Year: 2011 DOI: 10.17221/139/2010-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/139/2010-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201111-0005.txt Handle: RePEc:caa:jnljfs:v:57:y:2011:i:11:id:139-2010-JFS Template-Type: ReDIF-Article 1.0 Author-Name: V. Mansfeld Author-Workplace-Name: Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Forest Management Institute, Brandýs nad Labem, Czech Republic Title: Norway spruce in forest ecosystems of the Czech Republic in relation to different forest site conditions Abstract: The paper analyses the representation of Norway spruce (Picea abies [L.] Karst.) (hereinafter spruce) in relation to different conditions of forest sites. The analysis is based on data from the National Forest Inventory conducted in the Czech Republic in 2001-2004 (hereinafter NFI), stratified according to units of the Forest Site Classification System (Plíva 1971, 2000). Results of the analysis provide a structured image of the current share of spruce. The formerly published information on the natural share of spruce was corroborated and the recommended share of spruce in the target species composition of the spruce management system was analyzed. The analysis documents the applicability of NFI data in the technical discussion concerning the future form of forest ecosystems in the Czech Republic. The results can be used as the groundwork for concrete forest management decision-making and will contribute to the study of the biological diversity of forest ecosystems. Keywords: Norway spruce, biodiversity, Forest Site Classification System of the Czech Republic, National Forest Inventory Journal: Journal of Forest Science Pages: 514-522 Volume: 57 Issue: 11 Year: 2011 DOI: 10.17221/14/2011-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/14/2011-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201111-0006.txt Handle: RePEc:caa:jnljfs:v:57:y:2011:i:11:id:14-2011-JFS