Template-Type: ReDIF-Article 1.0 Author-Name: editors Title: INDEX OF VOLUME 64 Journal: Journal of Forest Science Pages: I-IV Volume: 64 Issue: 12 Year: 2018 DOI: 10.17221/11519-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/11519-JFS.html File-Format: text/html Handle: RePEc:caa:jnljfs:v:64:y:2018:i:12:id:11519-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Steen MAGNUSSEN Author-Workplace-Name: Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre, Victoria, Canada Title: An estimation strategy to protect against over-estimating precision in a LiDAR-based prediction of a stand mean Abstract: A prediction of a forest stand mean may be biased and its estimated variance seriously underestimated when a model fitted for an ensemble of stands (stratum) does not hold for a specific stand. When the sampling design cannot support a stand-level lack-of-fit analysis, an analyst may opt to seek a protection against a possibly serious over-estimation of precision in a predicted stand mean. This study propose an estimation strategy to counter this risk by an inflation of the standard model-based estimator of variance when model predictions suggest non-trivial random stand effects, a spatial distance-dependent autocorrelation in model predictions, or both. In a simulation study, the strategy performed well when it was most needed, but equally over-inflated variance in settings where less protection was appropriate. Keywords: forest enterprise inventory, risk analysis, stand-effects, spatial autocorrelation, simulation Journal: Journal of Forest Science Pages: 497-505 Volume: 64 Issue: 12 Year: 2018 DOI: 10.17221/120/2018-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/120/2018-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201812-0002.txt Handle: RePEc:caa:jnljfs:v:64:y:2018:i:12:id:120-2018-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Belkacem EL AMRANI Author-Workplace-Name: Department of Biology, Faculty of Science Dhar El Mehraz, Sidi Mohamed Ben Abdellah University, Fes, Morocco Author-Name: Mohammed BENDRISS AMRAOUI Title: Effects of some properties of cedar forest soils on secondary roots of Cedrus atlantica Manetti Abstract: The effect of textural and physicochemical characteristics of five cedar forest soils on 4- and 8-month-old seedlings of Cedrus atlantica Manetti was studied in a controlled growth chamber. During their growth, cedar seedlings show a change in the root architecture by the levels of Corg, N, P, and by the soil granulometry. The Tioumlilin soil conditions stimulate mainly the cumulative length and the number of secondary roots. However, the cedar forest soil of Tazekka predominates over most soils in its effect on growth by the balance of chemical elements and the high percentage of coarse particles. The analysis of the densities of secondary and tertiary roots and the cumulative length of secondary roots show four different root architectural development strategies of C. atlantica seedlings which may justify the low level of mycorrhization on young seedlings in the natural cedar forest soil. The variations of the root architectural parameters of C. atlantica seedlings are discussed in relation to the characteristics of cedar forest soils. Keywords: architecture, growth, plasticity, seedling, underground Journal: Journal of Forest Science Pages: 506-513 Volume: 64 Issue: 12 Year: 2018 DOI: 10.17221/69/2018-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/69/2018-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201812-0003.txt Handle: RePEc:caa:jnljfs:v:64:y:2018:i:12:id:69-2018-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Viktoriia LOVYNSKA Author-Workplace-Name: Department of Parks and Gardens, Faculty of Agronomy, Dnipro State Agrarian and Economic University, Dnipro, Ukraine Author-Name: Petro LAKYDA Author-Workplace-Name: Education and Research Institute of Forestry and Park Gardening, National University of Life and Environmental Sciences of Ukraine, Kyiv, Ukraine Author-Name: Svitlana SYTNYK Author-Workplace-Name: Department of Parks and Gardens, Faculty of Agronomy, Dnipro State Agrarian and Economic University, Dnipro, Ukraine Author-Name: Mykola KHARYTONOV Author-Workplace-Name: Department of Parks and Gardens, Faculty of Agronomy, Dnipro State Agrarian and Economic University, Dnipro, Ukraine Author-Name: Iryna PIESTOVA Author-Workplace-Name: Department of Geoinformation Technologies in Remote Sensing of the Earth, Scientific Centre for Aerospace Research of the Earth, Kyiv, Ukraine Title: LAI estimation by direct and indirect methods in Scots pine stands in Northern Steppe of Ukraine Abstract: Leaf area index (LAI) of Scots pine (Pinus sylvestris Linnaeus) in the Northern Steppe of Ukraine was estimated. LAI estimated directly (LAI d, destructive sampling) was compared with LAI determined by digital hemispherical photography (indirect method, LAI id) in Scots pine stands. The studies to determine LAI were performed in pine stands of the age ranging from 57 to 87 years. The high coefficient of determination between needle weight and crown diameter as dependent variables and stand age as an independent variable was found at the tree level. LAI values of the stands estimated by the direct method were higher than those obtained by the indirect method on average by 8.8%. The results obtained by both methods were used for LAI determination from allometric relationships with tree mensuration parameters and stand biometric characteristics. There was a more significant relationship between LAI id values and tree crown diameter, basal area of stands as independent variables. Keywords: Pinus sylvestris L., leaf area index, needle area, allometric equations, age structure Journal: Journal of Forest Science Pages: 514-522 Volume: 64 Issue: 12 Year: 2018 DOI: 10.17221/79/2018-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/79/2018-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201812-0004.txt Handle: RePEc:caa:jnljfs:v:64:y:2018:i:12:id:79-2018-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Stefan LINGNER Author-Name: Eiko THIESSEN Author-Workplace-Name: Institute of Agricultural Engineering, University of Kiel, Kiel, Germany Author-Name: Eberhard HARTUNG Author-Workplace-Name: Institute of Agricultural Engineering, University of Kiel, Kiel, Germany Title: Aboveground biomass estimation in linear forest objects: 2D- vs. 3D-data Abstract: Wood-chips of linear forest objects (hedge banks and roadside plantings) are used as sustainable energy supply in wood-chip heating systems. However, wood yield of linear forest objects is very heterogeneous and hard to estimate in advance. The aim of the present study was to compare the dry mass estimation potentials of two different non-destructive data: (i) Canopy area (derived from aerial images) and mean age at stump level (2D), (ii) volume of vegetation cover based on structure from motion (SfM) via unmanned aerial vehicle (3D). These two types of data were separately used to predict reference dry mass (ground truth) in eleven objects (5 hedge banks and 6 roadside plantings) in Schleswig-Holstein, Germany. The predicting potentials were compared afterwards. The reference dry mass was ascertained by weighing after harvesting and drying samples to constant weight. The model predicting reference dry mass using canopy area and mean age at stump level achieved a relative root mean square error (RMSE) of 52% (42% at larger combined plot sizes). The model predicting reference dry mass using SfM volume achieved a relative RMSE of 30% (16% at larger combined plot sizes). This result indicates that biomass is better described by volume of vegetation cover than by canopy area and age. Keywords: SfM, aerial images, hedge banks, roadside plantings, UAV, dry biomass Journal: Journal of Forest Science Pages: 523-532 Volume: 64 Issue: 12 Year: 2018 DOI: 10.17221/106/2018-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/106/2018-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201812-0005.txt Handle: RePEc:caa:jnljfs:v:64:y:2018:i:12:id:106-2018-JFS