Template-Type: ReDIF-Article 1.0 Author-Name: Steen Magnussen Author-Workplace-Name: Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre, Victoria BC, Canada Author-Name: Johannes Breidenbach Author-Workplace-Name: Norwegian Institute of Bioeconomy Research, Ås, Norway Title: Retrieval of among-stand variances from one observation per stand Abstract: Forest inventories provide predictions of stand means on a routine basis from models with auxiliary variables from remote sensing as predictors and response variables from field data. Many forest inventory sampling designs do not afford a direct estimation of the among-stand variance. As consequence, the confidence interval for a model-based prediction of a stand mean is typically too narrow. We propose a new method to compute (from empirical regression residuals) an among-stand variance under sample designs that stratify sample selections by an auxiliary variable, but otherwise do not allow a direct estimation of this variance. We test the method in simulated sampling from a complex artificial population with an age class structure. Two sampling designs are used (one-per-stratum, and quasi systematic), neither recognize stands. Among-stand estimates of variance obtained with the proposed method underestimated the actual variance by 30-50%, yet 95% confidence intervals for a stand mean achieved a coverage that was either slightly better or at par with the coverage achieved with empirical linear best unbiased estimates obtained under less efficient two-stage designs. Keywords: coverage, heteroscedasticity, one-per-stratum, quasi systematic, stand mean, two-stage sampling Journal: Journal of Forest Science Pages: 133-149 Volume: 66 Issue: 4 Year: 2020 DOI: 10.17221/141/2019-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/141/2019-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-202004-0001.txt Handle: RePEc:caa:jnljfs:v:66:y:2020:i:4:id:141-2019-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Tamar Khardzhiani Author-Workplace-Name: Department of Physical Geography, Vakhushti Bagrationi Institute of Geography, Ivane Javakhishvili Tbilisi State University, Tbilisi, Georgia Author-Name: Roman Maisuradze Author-Workplace-Name: Department of Geography, Faculty of Exact and Natural Sciences, Ivane Javakhishvili Tbilisi State University, Tbilisi, Georgia Title: Dominant woody species, their distribution and threat in Ambrolauri, Georgia Abstract: The paper presents the maps of ecosystems and 11 dominant woody species of Ambrolauri municipality, Georgia (Europe). Forest cover comprises approximately 68% of the study area, most of which are natural forests. Almost all formations of natural forests, depicted on the Georgian section of the Map of the Natural Vegetation of Europe, are still preserved in the research area. Nearly 40% of the forested land is broadleaf forest. Woody species are better preserved in the upper reaches of rivers, while an anthropogenic transformation is most visible in the Lower Racha Floodplain. A majority of the species discussed in the paper are included in the IUCN Red List of Threatened Species. The paper also deals with the issues of forest land degradation and threats imposed by invasive species to biodiversity. Keywords: woody species, IUCN Red List, vegetation mapping, natural forests Journal: Journal of Forest Science Pages: 150-158 Volume: 66 Issue: 4 Year: 2020 DOI: 10.17221/120/2019-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/120/2019-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-202004-0002.txt Handle: RePEc:caa:jnljfs:v:66:y:2020:i:4:id:120-2019-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Hassan Pourbabaei Author-Name: Ali Salehi Author-Workplace-Name: Department of Forestry, Faculty of Natural Resources, University of Guilan, Somehsara, Iran Author-Name: Sepide Sadat Ebrahimi Author-Workplace-Name: Department of Forestry, Faculty of Natural Resources, University of Guilan, Somehsara, Iran Author-Name: Fazel Khodaparasrt Author-Workplace-Name: Department of Forestry, Faculty of Natural Resources, University of Guilan, Somehsara, Iran Title: Variations of soil physicochemical properties and vegetation cover under different altitudinal gradient, western Hyrcanean forest, north of Iran Abstract: This study was done to quantify the amount of soil organic matter and to evaluate physicochemical properties and vegetation cover changes along the altitudinal gradient. Nine altitudinal transects were selected from 100 m a.s.l. to 1 700 m a.s.l. Then, 160 circular plots of 1 000 m2 area with a distance of 150 m from each other were studied. Soil texture, bulk density, particle density, soil base saturation, phosphorus and potassium values did not indicate any specific variation pattern. Whereas pH decreased powerfully, the highest and the lowest value of pH was measured at 100 m a.s.l. and 1 700 m a.s.l., respectively. Soil organic carbon content increased significantly with increasing altitude (P ≤ 0.01). Density of trees decreased dramatically from 100 to 900 m a.s.l., whereas this trend was ascending from 1 100 to 1 700 m a.s.l. Density of shrub species increased with increasing altitude along the gradient and the highest value was revealed at 1 300 m a.s.l. The highest percentage of herbaceous species cover was found at a lower altitude and a decreasing trend was found along the altitudinal gradient. Keywords: soil organic carbon, vegetation cover, species richness, human impact, altitudinal gradient Journal: Journal of Forest Science Pages: 159-169 Volume: 66 Issue: 4 Year: 2020 DOI: 10.17221/136/2019-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/136/2019-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-202004-0003.txt Handle: RePEc:caa:jnljfs:v:66:y:2020:i:4:id:136-2019-JFS Template-Type: ReDIF-Article 1.0 Author-Name: Ali Ghomi-Avili Author-Workplace-Name: Faculty of Natural Resources, Tarbiat Modares University, Noor, Mazandaran, Iran Author-Name: Moslem Akbarinia Author-Workplace-Name: Faculty of Natural Resources, Tarbiat Modares University, Noor, Mazandaran, Iran Author-Name: Seyed-Mohsen Hosseini Author-Workplace-Name: Faculty of Natural Resources, Tarbiat Modares University, Noor, Mazandaran, Iran Author-Name: Mohammad-Hasan Talebian Author-Workplace-Name: Cultural Heritage Training Center, Tehran, Iran Author-Name: Hannes Dieter Knapp Author-Workplace-Name: Michael Succow Foundation, Berlin, Germany Title: Fuzzy and Boolean operation based modelling for evaluation of ecological capability in the Hyrcanian Forests Abstract: Over the past four decades, management plan based on the Boolean Ecological Capability model has caused major problems in the management of the Hyrcanian Forests. The aim of this study is to evaluate ecological capability of five proposed sites including Golestan National Park, Afra Takhteh Yew Forest, Kojoor Forest, Cypress Woodland of Hassanabad-e Chalous, Lomer forest along the Hyrcanian region from east to west, using both Boolean and fuzzy logic and to compare these two models. A total of 10 important factors including slope, aspect, elevation, soil types, soil erosion, soil transformation, canopy cover, the value of species, distance to streams and climate were investigated in this study. The results show that elevation, slope and aspect have the most important role in the classification of the studied area. The results of model validation with field data indicate that the fuzzy gamma model shows the better assessment, accuracy and reliability compared to the Boolean model. Based on the obtained results we suggest the fuzzy-based operation model in sustainable protection planning in the Hyrcanian Forests. Keywords: fuzzy gamma, model validation, sustainable protection, Golestan National Park Journal: Journal of Forest Science Pages: 170-184 Volume: 66 Issue: 4 Year: 2020 DOI: 10.17221/130/2019-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/130/2019-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-202004-0004.txt Handle: RePEc:caa:jnljfs:v:66:y:2020:i:4:id:130-2019-JFS