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Effect of growing altitude, particle drying temperature and press temperature on some technological properties of particleboard produced from black alder wood

Kumaş İlknur, Aras Uğur, Kalaycioğlu Hulya, Serdar Bedri, Yel Husnu

Drewno : prace naukowe, doniesienia, komunikaty

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2021

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vol. 64, nr 207

59--71

EN

This study investigated the effects of the growing altitude, particle drying temperature and press temperature on some technological properties of particleboard produced from black alder wood. The particles were produced from wood taken from the KTÜ Campus and from Çamoba in Trabzon. Production and tests of the experimental particleboards were carried out at Kastamonu Integrated Wood Company. In production of the particleboards, wood from different growing altitudes [50 m and 250 m] was used, and different drying temperatures [120 and 150°C] and press temperatures [150 and 200°C] were applied. Mechanical, physical and anatomical properties of the produced boards were investigated. According to the results, the mechanical properties deteriorate when the altitude increases. Increasing the particle drying temperature and press temperature had a positive effect on dimensional stability. A high press temperature improved the mechanical properties of the boards. In addition, growing altitude had an effect on anatomical properties: when the altitude increased, the diameter of vessels narrowed, the number of vessels per mm2 increased, and fiber length decreased. This resulted in a deterioration in mechanical properties at the higher altitude.

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Damage caused by harvester head feed rollers to alder, pine and spruce

Karaszewski Z., Łacka A., Mederski P. S., Noskowiak A., Bembenek M.

Drewno : prace naukowe, doniesienia, komunikaty

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2016

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vol. 59, nr 197

77--88

EN

The harvester head causes damage to the bark and wood on the lateral surface of the processed assortment. The severity of the damage may be influenced by the construction of the harvester head and tree species characteristics, such as bark thickness and wood hardness. The study aimed to recognise and compare damage caused to hardwood and softwood. Wood from alder, pine and spruce was harvested using a Valmet 911.4 harvester equipped with a 360.2 head. Logs measuring 2.40 and 2.50 m in length were used in this study. The depth of the damage caused by the feed roller spikes was measured using a digital caliper. Comparison of these defects across the three species revealed that as bark thickness increased so the depth of damage to the timber decreased. Damage to the alder logs in the form of dents and gouged timber fibres was shallow: from 1.7 to 3.7 mm, and significantly less than that to the softwood logs: in the pine from 5.9 to 7.8 mm, and in the spruce from 3.9 to 5.6 mm. Damage to the middle and top logs for each species was similar and depth varied little along the entire length of the processed assortment. Such damage only slightly lowered the quality of the alder wood, which had the thickest bark. Application of the Valmet 911.4 harvester caused less damage to the alder wood than to the softwood (pine and spruce).

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Oddziaływanie dwutlenku siarki na wybrane gatunki liściastych drzew leśnych

Bęś A., Baciak M.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2015

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Vol. 24, No. 2

155--166

PL

Działanie dwutlenku siarki na drzewa powoduje żółknięcie ich liści, ubytek chlorofilu, co ma przełożenie na zahamowanie procesu fotosyntezy. Rośliny są bardziej narażone na działanie SO2 w dzień, kiedy mają otwarte aparaty szparkowe, przez które wnika on do wnętrza komórek. Podwyższone stężenie SO2 powoduje rozkład chlorofilu, zakłócenie fotosyntezy, jak również zatrzymanie asymilacji, co w rezultacie prowadzi do zwiększonej wrażliwości drzew na czynniki klimatyczne, zmniejsza odporność drzewostanu na występowanie chorób oraz szkodników lasów. Celem prowadzonego eksperymentu było wykazanie wrażliwości olchy czarnej i dębu szypułkowego na zanieczyszczenia gazowe, podczas ekspozycji tych roślin w podwyższonych stężeniach dwutlenku siarki. Oddziaływanie dwutlenku siarki na liście określono poprzez oznaczenie zawartości chlorofili a i b metodą ekstrakcji chlorofilu dimetylosulfotlenkiem (DMSO). Olcha czarna wykazywała większą wrażliwość na działanie SO2 niż dąb szypułkowy. Działanie na rośliny dwutlenkiem siarki w znacznym stopniu obniżyło zawartości chlorofili a i b, a co za tym idzie intensywność fotosyntezy. Uszkodzenie wywołane przez SO2 na liściach olchy objawiało się w postaci nekroz, a w przypadku liści dębu uszkodzenia przyjmowały postać żółtych chloroz i pojedynczych brązowych nekroz.

EN

Exposure of plants to sulfur dioxide causes yellowing of the green portions of the leaf and chlorophyll destruction, which inhibits photosynthesis. Plants incur more damage from sulfur dioxide during daytime, when stomata are open in the presence of sunlight and sulfur dioxide can penetrate into leaf cells. High sulfur dioxide concentrations lead to chlorophyll degradation, photosynthesis disturbance and inhibition of assimilation in leaves, which increases the vulnerability of trees to climatic factors and decreases their resistance to diseases and pests. The aim of this study was to determine the sensitivity of black alder and English oak to gaseous air pollution. The trees were exposed to increased sulfur dioxide concentrations. The effect of sulfur dioxide on leaves was evaluated based on the concentrations of chlorophyll a and chlorophyll b extracted using dimethyl sulfoxide (DMSO). The black alder was more susceptible to sulfur dioxide than the English oak. Exposure of trees to sulfur dioxide considerably reduced the concentrations of chlorophyll a and chlorophyll b, and the rate of photosynthesis. Injury to foliage caused by sulfur dioxide appeared in the form of necrotic lesions in the black alder, and yellow chlorosis spots and individual brown necrotic patches in the English oak.

4

Analiza zmienności i korelacji wybranych cech fizycznych nasion olszy czarnej

Kaliniewicz Z., Trojanowski A.

Inżynieria Rolnicza

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2011

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R. 15, nr 8

167-172

PL

Dokonano pomiarów prędkości krytycznej unoszenia, grubości, szerokości, długości, kąta tarcia ślizgowego i masy oraz wyznaczono współczynniki sferyczności nasion olszy czarnej, zebranych z 3 różnowiekowych drzewostanów nasiennych. Do opisu i analizy cech wykorzystano analizę wariancji z klasyfikacją pojedynczą, korelację oraz regresję jednej zmiennej i wielu zmiennych.

EN

Measures of critical speed of lifting, thickness, width, length, sliding friction angle and mass were taken. Moreover, spherical coefficient of black alder seeds collected from three seed tree stands of different age was determined. The analysis of variance with single classification, correlation and regression of one variable and many variables was used for description and analysis.

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Differences in defence strategies against herbivores between two pioneer tree pecies: Alnus glutinosa (L.) Gaertn. and Betula pendula Roth.

Giertych Marian J., Karolewski Piotr, Żytkowiak Roma, Oleksyn Jacek

Polish Journal of Ecology

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2006

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Vol. 54, nr 2

181-187

EN

The different defence strategies of trees against herbivores are very often connected with succession status, leaf life span and the level of secondary metabolites. We examined the effect of simulated leaf grazing on the differences in the leaf life span and defence chemistry of two pioneer tree species that belongs to the same family (Betulaceae), black alder (Alnus glutinosa (L.) Gaertn.) and European white birch (Betula pendula Roth.). At the beginning of the growing season, mature leaves were perforated using a paper punch. The holes removed about 10% of the leaf surface. Each species was represented by six trees - one branch was chosen for perforation and one branch as a control. All leaves were counted every week until their abscission. Additional damages caused by grazing insects were also noted.Undamaged birch leaves were held much longer than those of alder. The average difference in half leaf life span between control and perforated leaves was 28 days in birch and 6 in alder. The control unperforated alder leaves were significantly (P <0.05) more often grazed by insects than those that were perforated. Leaf perforation in alder increase phenolic concentrations in the new, young leaves. In birch we did not observe these changes.The comparison of alder and birch indicate that the species with similar successional status can have different strategies of leaf defence. The birch leaves were characterized by a longer leaf life span, constitutive defence, a lack of induced defence accumulation of phenolics and earlier shedding of damaged leaves in comparison to the control. The black alder foliage had a shorter leaf life span, induced defence reaction (producedmore phenolics after perforation), and only slightly earlier shedding of damaged leaves than the control.

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Black alder (Alnus glutinosa Gaertn.) as a pioneer species in regeneration of fresh oak-linden-hornbeam forest (Tilio-Carpinetum typicum Traczyk 1962) in Białowieża Forest (East Poland)

Obidziński A.

Polish Journal of Ecology

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2004

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Vol. 52, nr 4

533-551

EN

Black alder (alnus glutinosa Gaertn.) is considered a hygrophilous species. The aim of the research was to find out if black alder may play a role of a pioneer species in the habitat of Tilio-Carpinetum typicum Traczyk 1962, i.e. fresh oak-linden-hornbeam forest. The investigation was carried out in Białowieża Forest (East Poland). The vegetation was examined with the Braun-Blanquet (1928) method. Soil diagnosis was based on the analysis of soil profiles and a network of test borings. Ecological differentiation of the phytocoenoses in terms of light, humidity, and fertility factors was analysed by indicator values of vascular plants. Obtained results showed that black alder may play the role of a pioneer species in the habitat of fresh oak-linden-hornbeam forest (Tilio-Carpinetum typicum). This phenomenon may occur on haplic luvisols underlayed with clay, after clear-cuts bigger than 1 hectare. Secondary plant communities with black alder that develop in such conditions reveal characteristics of wet oak-linden-hornbeam forest (Tilio-Carpinetum stachyetosum Traczyk 1962).