Template-Type: ReDIF-Article 1.0 Author-Name: Jakub ČERNÝ Author-Workplace-Name: Forestry and Game Management Research Institute, Strnady, Opočno Research Station, Opočno, Czech Republic Author-Workplace-Name: Department of Silviculture, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Author-Name: Jan KREJZA Author-Workplace-Name: Global Change Research Institute of the Czech Academy of Sciences, Brno, Czech Republic 4 Centre MendelGlobe, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Author-Name: Radek POKORNÝ Author-Workplace-Name: Department of Silviculture, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Author-Name: Pavel BEDNÁŘ Author-Workplace-Name: Forestry and Game Management Research Institute, Strnady, Opočno Research Station, Opočno, Czech Republic Title: LaiPen LP 100 - a new device for estimating forest ecosystem leaf area index compared to the etalon: A methodologic case study Abstract: Fast and precise leaf area index (LAI) estimation of a forest stand is frequently needed for a wide range of ecological studies. In the presented study, we compared side-by-side two instruments for performing LAI estimation (i.e. LaiPen LP 100 as a "newly developed device" and LAI-2200 PCA as the "world standard"), both based on indirect optical methods for performing LAI estimation in pure Norway spruce (Picea abies (Linnaeus) H. Karsten) stands under different thinning treatments. LAI values estimated by LaiPen LP 100 were approximate 5.8% lower compared to those measured by LAI-2200 PCA when averaging all collected data regardless of the thinning type. Nevertheless, when we considered the differences among LAI values at each measurement point within a regular grid, LaiPen LP 100 overestimated LAI values compared to those from LAI-2200 PCA on average by 1.4%. Therefore, both instruments are comparable. Similar LAI values between thinning from above (A) and thinning from below (B) approaches were indirectly detected by both instruments. The highest values of canopy production index and leaf area efficiency were observed within the stand thinned from above (plot A). Keywords: LAI-2200 PCA, indirect LAI, Norway spruce, thinning, canopy production index, leaf area efficiency Journal: Journal of Forest Science Pages: 455-468 Volume: 64 Issue: 11 Year: 2018 DOI: 10.17221/112/2018-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/112/2018-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201811-0001.txt Handle: RePEc:caa:jnljfs:v:64:y:2018:i:11:id:112-2018-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Benyamin MATINNIA Author-Name: Aidin PARSAKHOO Author-Workplace-Name: Department of Forestry, Faculty of Forest Science, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran Author-Name: Jahangir MOHAMADI Author-Workplace-Name: Department of Forestry, Faculty of Forest Science, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran Author-Name: Shaban SHATAEE JOUIBARY Author-Workplace-Name: Department of Forestry, Faculty of Forest Science, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran Title: Study of the LiDAR accuracy in mapping forest road alignments and estimating the earthwork volume Abstract: Today, differential geographical position system and total station devices are improving the accuracy of positioning information, but in critical locations such as steep slopes and closed canopy cover, the device accuracy is limited. Moreover, field surveying in this technique is time-consuming and expensive. For this reason, remote sensing technique such as light detection and ranging (LiDAR) laser scanner should be used in field measurements. The objective of this study was to evaluate and compare precision and time expenditure of total station and airborne LiDAR in producing horizontal and vertical alignments and estimating earthwork volume of two proposed forest roads in a deciduous forest of Iran. To investigate this task, the geographical position of proposed forest roads were detected by differential geographical position system and then marked on land. Mentioned roads were taken again with Leica Total Station (LTS) on control points with same 5 m intervals from start point. Recent data served as a reference value for comparison with LiDAR measurements. The data were processed in Civil 3D, Fusion and Leica geo office software. Results showed that in comparison to field-surveyed routes by LTS, the LiDAR-derived routes exhibited a horizontal accuracy of 0.23 and 0.47 m and vertical accuracy of 0.31 and 0.66 m for road 1 and road 2, respectively. The LiDAR-derived sections every 1 m exhibited cut and fill accuracy of 2.39 and 3.18 m3 for road 1 and 2.98 and 5.60 m3 road 2, respectively. In this study, it was proved that the road project can be prepared faster by LiDAR than that of LTS. Therefore, high accuracy of road projection by LiDAR is useful for terrain analysis without the need for field reconnaissance. Keywords: airborne LiDAR, Leica Total Station, mapping proposed road, accuracy estimation, deciduous forest canopy cover Journal: Journal of Forest Science Pages: 469-477 Volume: 64 Issue: 11 Year: 2018 DOI: 10.17221/87/2018-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/87/2018-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201811-0002.txt Handle: RePEc:caa:jnljfs:v:64:y:2018:i:11:id:87-2018-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Vlastimil MURGAŠ Author-Name: Ivan SAČKOV Author-Workplace-Name: National Forest Centre - Forest Research Institute Zvolen, Zvolen, Slovak Republic Author-Name: Maroš SEDLIAK Author-Workplace-Name: National Forest Centre - Forest Research Institute Zvolen, Zvolen, Slovak Republic Author-Name: Daniel TUNÁK Author-Workplace-Name: Department of Forest Management and Geodesy, Faculty of Forestry, Technical University in Zvolen, Zvolen, Slovak Republic Author-Name: František CHUDÝ Author-Workplace-Name: Department of Forest Management and Geodesy, Faculty of Forestry, Technical University in Zvolen, Zvolen, Slovak Republic Title: Assessing horizontal accuracy of inventory plots in forests with different mix of tree species composition and development stage Abstract: Global navigation satellite systems (GNSS) have a wide range of applications in forest industry, including forest inventory. In this study, the horizontal accuracy of 45 inventory plots in different forest environments and 5 inventory plots under open sky conditions were examined. The inventory plots were located using a mapping-grade GNSS receiver during leaf-on season in 2017. True coordinates of the plot centres were acquired using a survey-grade GNSS receiver during leaf-off season in 2018. A study was conducted across a range of forest conditions in the forest unit Vígľaš, which is located in Slovakia (Central Europe). Root mean square error of horizontal accuracies was 8.45 m in the plots under forest canopy and 6.61 m under open sky conditions. We note decreased positional errors in coniferous forests as well as in younger forests. However, results showed that there is no statistically significant effect of tree species composition and stand age on horizontal accuracy. Keywords: GNSS, positional error, satellite navigation, spatial coordinates Journal: Journal of Forest Science Pages: 478-485 Volume: 64 Issue: 11 Year: 2018 DOI: 10.17221/92/2018-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/92/2018-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201811-0003.txt Handle: RePEc:caa:jnljfs:v:64:y:2018:i:11:id:92-2018-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Ondřej ŠPULÁK Author-Name: Jiří SOUČEK Author-Workplace-Name: Forestry and Game Management Research Institute, Strnady, Opočno Research Station, Opočno, Czech Republic Author-Name: Jakub ČERNÝ Author-Workplace-Name: Forestry and Game Management Research Institute, Strnady, Opočno Research Station, Opočno, Czech Republic Title: Do stand structure and admixture of tree species affect Scots pine aboveground biomass production and stability on its natural site? Abstract: The paper analyses stand structure and production on two experimental forest stand series of mature pure and mixed Scots pine stands, growing on natural Scots pine sites in the Czech Republic. Sessile oak was the main admixed species. In mixed stands, Scots pine constituted the dominant level of the stand, admixed species grew mostly as subdominants. Admixture increased stand densities and aboveground biomass production compared to pure stands. Sessile oak with the 20-30% number share within the Scots pine stand led to an increase of the Scots pine tree dimensions and mean stem merchantable wood (DBH ≥ 7 cm) volume compared to the pure Scots pine stand of similar density. The Scots pine and sessile oak slenderness ratios increased in mixed stands compared to monocultures, however, the stand mechanical stability was not threatened. Keywords: Pinus sylvestris, sessile oak, Norway spruce, mixture, volume, stand indices Journal: Journal of Forest Science Pages: 486-495 Volume: 64 Issue: 11 Year: 2018 DOI: 10.17221/117/2018-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/117/2018-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201811-0004.txt Handle: RePEc:caa:jnljfs:v:64:y:2018:i:11:id:117-2018-JFS