Turkish Journal of Forestry

45-55

Authors: A. Haluk TÜRKER

This research was carried out to determine and compare the essential oil components of regenerated plants and calli grown under in vitro conditions with in vivo plants of Origanum syriacum var. bevanii taxon used as donor. The essential oil components of the donor plants grown with cuttings taken from the native environment and regenerant plants and calli grown from the various explants in vitro supplemented with different concentrations of the plant growth regulators were determined by Gas Chromatography-Mass Spectrometry (GC-MS). In result of the research, it was determined that the essential oil components of donor and regenerant plants and calli were quite different from each other. It was determined that was Carbamic Acid (26.49%) and Carvacrol (19.67%) in essential oil from the regenerant plants while was Carvacrol (36.28%) and ortho-Cymene (19.76%) in essential oil from the donor plants as major components. It was determined that was 64.82% Ethanol, 57.23% 1,2-Propanediol, 55.11% L(+)-Lactic acid, 53.53% Methyltartronic acid, 52.16% 4-Penten-2-ol ve 38.47% 2-Methoxycinnamic acid in essential oil from the callus as major components disparately. 2-Methoxycinnamic acid, which is one of the initial components in the formation of simple phenolic compounds, was found at the highest rate (38.4%) in the callus developed from the stem node explant, compared to the other callus developed from the leaf explant, and constitutes the main component. Therefore, according to the results of the analysis, it was determined that the callus developed from the stem node explant gave promising results in the formation of secondary metabolites.

61-68

Authors: Samet BAYTAŞ, Mehmet SEKİ

In this study, single and double entry over- and under-bark tree volume equations have been developed for Kazdağı Fir (Abies nordmanniana subsp. equi-trojani) stands within the boundaries of Safranbolu Forest Enterprise. The over- and under-bark volume values of 153 sample trees taken from different stand structures were used as the study material. Ten tree volume equations, five single- and five double-entry, were developed for over- and under-bark tree volume estimations. Four goodnes-of-fit criteria, including adjusted coefficient of determination, bias, mean absolute error, and root mean square error, were used to determine the most successful models. The suitability of the equations developed for the region was checked with an independent data set as well Wilcoxon test, and it was concluded that the equations were suitable for the study area (p>0.05). All tree volume equations proposed for the region had a coefficient of determination value over 0.95. In addition, the mean bias of the single- and double-entry models found to be the most successful for the region were calculated as -0.0211 m3 and -0.0122 m3 for the over-bark volume estimations, and -0.0201 m3 and 0.0045 m3 for the under-bark volume estimations, respectively. Single- and double-entry tree volume tables were prepared for over- and under-bark volume estimations by using the successful equations obtained as a result of the study.

80-84

Authors: Funda ÖZDEMİR DEĞİRMENCİ, Asiye ULUĞ

Black poplar is an economically important tree species that spreads in the Eastern and Central Anatolian regions of Türkiye and is used extensively in wood production. In addition to being used as a model organism for raw material production in breeding programs all over the world, its natural populations and plantations are used extensively, especially in Europe, due to its environmental plasticity and contribution to biodiversity. The habitat of the species is decreasing day by day and the continuity of the species is threatened in parallel with the increase in human activities such as planting fields and establishing hydroelectric power plants on the riverbanks where they naturally spread. In this study, genetic identity was given to individuals in black poplar populations distributed in the Aras River with 16 microsatellite markers. A high level of expected and observed heterozygosity was found in the populations. It turned out that the populations sampled from the sections of the Aras River between Iğdır-Kars and Erzurum-Kars originated from two genetic groups. It has been observed that there is a low rate of genetic differentiation between these two genetic groups due to high gene flow. The genetic data obtained can be used in the development of in-situ/ex-situ conservation programs and breeding programs for black poplar populations distributed in the Aras River.

99-110

Authors: Kenan OK, Güven KAYA

Research areas of the study is Çerkeş Forest Enterprise. In the study, demand of logs of third class normal length (3SNB) Austrian pine, Scotch pine, and fir logs included in the 13 sales by auction conducted between 2017 (May) and 2018 (June) were investigated. The main aim of the research is to calculate the demand functions of the products examined, to compare the functions regarding characteristics of statistic and economic by using two different approaches defined as “total sales volume” and “total offer level” and the data sets produced from the same sales. Secondary aim of the study is to discuss the possibilities of using the appropriate demand functions for improving the marketing programs. Multiple correlation and multiple linear regression analysis were used in the research. As a result, it has been determined that multiple correlation and regression analyzes based on the data produced with the total offer levels approach can produce the log demand equations for Austrian pine, Scotch pine, and fir with a higher statistical confidence level and that the equations can reflect the economic rules more accurately. Negative cross elasticities calculated from demand equations generated for the Çerkeş Forest Enterprise show that the fir logs and Austrian pine logs are the complementary goods. Positive values of cross elasticities prove that Austrian pine - Scotch pine logs and fir - Scotch pine logs are substitute goods in the Çerkeş.

122-133

Authors: Doğu RAMAZANOĞLU, Ferhat ÖZDEMİR

Wood preservation plays a vital role in maintaining wood products' structural and aesthetic properties. Traditional methods, including chemical treatments, preservatives, and coatings, have been utilized for wood protection, but sustainable alternatives are sought due to their negative environmental and health impacts. The utilization of nanomaterials presents a promising avenue for wood protection. In this study, nanoparticles were applied to lignocellulosic materials using the impregnation method to enhance solid wood’s water and fire resistance without needing additional energy. This research aimed to identify a cost-effective and energy-efficient approach for large-scale wood production while introducing innovative and competitive materials in the wood industry. Surface modification and characterization analyses, including SEM-EDX and Optical Profilometer studies, TGA-DTA analysis for thermal strength assessment, % water uptake test for water resistance evaluation, and PCE-CSM 10 spectrophotometer measurements to determine color change parameters, were conducted. Functionalized wood surfaces treated with zinc oxide (ZnO), chitosan (Ch), and tin dioxide (SnO2) nanoparticles exhibited water uptake values of 64%, 71%, and 73%, respectively. Following the salinization process using TEOS, the water uptake values decreased to 58%, 59%, and 60% for the respective surfaces. Based on the TGA and DTA results, the W-ZnO-TEOS sample demonstrated superior mass protection, with a significant weight loss of 62.1% (5.717 mg) at 340-375°C and 14.4% (1.328 mg) at 381-439°C. This was followed by the W-SnO2-TEOS sample, which exhibited a weight loss of 46.3% (7.050 mg) at 301-353°C and 15.4% (2.345 mg) at 431-469°C. The W-Ch-TEOS sample displayed a weight loss of 66.4% (8.242 mg) at 342-365°C and 18.8% (2.335 mg) at 448-476°C. Overall, the W-SnO2-TEOS sample demonstrated the highest water resistance, while the W-ZnO-TEOS sample exhibited the most effective fire protection capabilities.

139-149

Authors: Mücahit ŞAHİN, İbrahim Halil BAŞBOĞA

This study aims to determine the effects of the evaluation of beech woods obtained from thinning, which are in the firewood class, and also beech cupulas as a filler in the manufacturing of wood plastic composite (WPC) on the technological properties of the composites. For this purpose, polypropylene (PP) based WPC production was carried out with the usage of 2 different fillers rate (0 or 50%) and three different types of lignocellulosic fillers (50% beech, 25% beech + 25% cupula or 50% cupula). In addition, maleic anhydride grafted polypropylene (MAPP) in 2 different ratios (0% and 3%) was used as a compatibilizing agent and the effects of MAPP usage were investigated. The mechanical (tensile strength, elongation at break, flexural strength, modulus of elasticity and impact strength) and physical (density and hardness) properties of the produced WPCs were determined in accordance with the relevant standards. As a result, when the lignocellulosic fillers were compared within themselves, it was seen that the highest mechanical properties were obtained with the usage of beech wood flour. The mechanical strength properties were negatively affected by the addition of cupula flours into the composite materials, and the mechanical properties were negatively affected by the increase in the cupula rates. Generally, the usage of MAPP has improved the mechanical properties of the WPCs. In Composite groups produced by using only beech wood flour together with MAPP, the highest values were obtained in all mechanical properties except elongation at break, and significant increases were observed compared to the control group. As a result of the study, PP-based WPC productions, in which beech wood flours and cupula flours are used as fillers, have been successfully carried out. It is thought that better performance will be achieved when beech wood flours are used alone or their cupulas are used together with beech wood flours and less than 25%.