Template-Type: ReDIF-Article 1.0 Author-Name: Y. Lei Author-Workplace-Name: Research Institute of Resource Information and Techniques, Chinese Academy of Forestry, Beijing, China Author-Name: J. Shi Author-Workplace-Name: Academy of Forest Inventory and Planning, State Forestry Administration, Beijing, China Author-Name: T. Zhao Author-Workplace-Name: School of Information Science and Technology, Beijing Forestry University, Beijing, China Title: Efficiency of adaptive cluster sampling and traditional sampling for coastal mangrove in Hainan of China Abstract: Based on two species of Coastal Mangrove in Hainan of China, Sonneratia Apetala Buch-Ham and Sonneratia caseoli, we estimated the density of the two species to evaluate the efficiency of adaptive cluster sampling (ACS), simple random sampling (SRS) and traditional systematic sampling (SYS). Our initial experimental designs for ACS consisted of 5 unit areas, 6 initial sampling proportions, 4 initial sample sizes and 5 criterion values in 1,000 repetitions. From the aspect of factors influencing efficiency, we analysed the efficiency of ACS in various designs. We also compared the efficiencies of the three methods on the indexes of the relative error, the variance of density estimator and the relative sampling efficiencies. We found that ACS yielded smaller variance than the traditional sampling methods. ACS was a powerful sampling method when a population was spatially aggregated. We also determined the optimum unit area for the two species studied using the two estimators (HT and HH) of adaptive cluster sampling. They were 20 m2 (2 × 10 m), 15 m2 (3 × 5 m) for S. Apetala Buch-Ham and 25 m2 (5 × 5 m), 15 m2 (3 × 5 m) for S. caseolari, respectively. Keywords: adaptive cluster sampling, Horvitz-Thompson estimator, Hansen-Hurwitz estimator, simple random sampling, systematic sampling Journal: Journal of Forest Science Pages: 381-390 Volume: 58 Issue: 9 Year: 2012 DOI: 10.17221/80/2011-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/80/2011-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201209-0001.txt Handle: RePEc:caa:jnljfs:v:58:y:2012:i:9:id:80-2011-JFS Template-Type: ReDIF-Article 1.0 Author-Name: E. Kula Author-Workplace-Name: Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Author-Name: A. Pešlová Author-Workplace-Name: Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Author-Name: P. Martinek Author-Workplace-Name: Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Title: Effects of nitrogen on growth properties and phenology of silver birch (Betula pendula Roth) Abstract: Effects of stress caused by differentiated inputs of nitrogen after the application of ammonium nitrate (NH4NO3) on silver birch (Betula pendula Roth) were monitored in a greenhouse. The applied ammonium nitrate did not affect pH values but increased differently the content of nitrogen in soil and leaves. With increased inputs of nitrogen the height and diameter increment of birch also decreased, budbreak was delayed and the autumn leaf-fall slowed down. Frost heaving of shoots occurred particularly in the lower half of the birch stem. With the increasing content of nitrogen in leaves the content of phosphorus decreased and the level of potassium increased. Keywords: nitrogen, silver birch, stress, phenology of budbreak, leaf-fall, frost heaving Journal: Journal of Forest Science Pages: 391-399 Volume: 58 Issue: 9 Year: 2012 DOI: 10.17221/109/2011-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/109/2011-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201209-0002.txt Handle: RePEc:caa:jnljfs:v:58:y:2012:i:9:id:109-2011-JFS Template-Type: ReDIF-Article 1.0 Author-Name: O. Mauer Author-Workplace-Name: Department of Forest Establishment and Silviculture, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Author-Name: E. Palátová Author-Workplace-Name: Department of Forest Establishment and Silviculture, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Title: Root system development in Douglas fir (Pseudotsuga menziesii [Mirb.] Franco) on fertile sites Abstract: The paper analyses the root system development in the artificially established stands of Douglas fir aged 10, 20, 30, 60 and 80 years on aerated soils (Cambisols) without skeleton. On these sites, the Douglas fir develops a uniform root system of substitute taproots and anchors, which has great predispositions to assure the good mechanical stability of trees as well as its resistance to sudden changes in upper soil horizons. Several anchors growing in positive geotropic direction shoot from the stem base, several slant anchors shooting from the side of the stem base turn into the positive geotropic direction of growth. In humus horizons, horizontal skeletal roots shoot from the stem base, which turn into lower soil horizons in an "elbow-pipe" manner and from which shoot positively geotropically growing anchors. Trees of Douglas fir develop this type of root system already at an age of twenty years. Keywords: Douglas fir, root system, fertile sites Journal: Journal of Forest Science Pages: 400-409 Volume: 58 Issue: 9 Year: 2012 DOI: 10.17221/94/2011-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/94/2011-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201209-0003.txt Handle: RePEc:caa:jnljfs:v:58:y:2012:i:9:id:94-2011-JFS Template-Type: ReDIF-Article 1.0 Author-Name: K. Rejšek Author-Workplace-Name: Department of Geology and Pedology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Brno, Czech Republic Author-Name: M. Mišič Author-Workplace-Name: Geological Survey of Slovenia, Ljubljana, Slovenia Author-Name: F. Eichler Author-Workplace-Name: Liberec-Františkov, Czech Republic Title: Sustainable forestry and iron compounds in karstic soils: qualitative and semi-quantitative results focused on the occurrence of Fe-compounds on mineral particles Abstract: Relic karstic soils in nine localities in the Dinaric Karst in Slovenia, five localities in the Moravian Karst and four localities in the Bohemian Karst were sampled for soil scientific, mineralogical and petrological studies focused on the presentation of descriptive aspects of particular iron compounds. The macroscopy and microscopy of Fe2+ and Fe3+ compounds were determined and an interpretation of these data was performed aimed at describing sources and their palaeotransports. The presented results show that the studied karstic soils have a heterogeneous petrographical and mineralogical composition when, depending on circumstances, hematite does not dominate and goethite prevails over it or it is an opposite. Results from the chosen methods reinforce sources of the new materials as the crucial factor for the studied karstic soils. Keywords: iron oxides, iron hydroxides, karstic soils, soil formation in karsts Journal: Journal of Forest Science Pages: 410-424 Volume: 58 Issue: 9 Year: 2012 DOI: 10.17221/106/2011-JFS File-URL: http://jfs.agriculturejournals.cz/doi/10.17221/106/2011-JFS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/jfs-201209-0004.txt Handle: RePEc:caa:jnljfs:v:58:y:2012:i:9:id:106-2011-JFS