American tulipwood (Liriodendron tulipifera L.) as an innovative material in CLT technology

2021 ◽  
Vol 115 ◽  
pp. 18-28
Author(s):  
Teresa Kłosińska

American tulipwood (Liriodendron tulipifera L.) as an innovative material in CLT technology. CLT (cross laminated timber, X-Lam) is one type of engineered wood products. The first idea of CLT was presented in the seventies of the last century. It is manufactured with timber boards placed side by side commonly with 3, 5 and 7 layers glued at 90 degrees to adjacent layer. The CLT production technology was developed for softwood. The main species in CLT production is Norway spruce (Picea abies L.) and less often White fir (Abies alba Mill.). Hardwood is also used more and more for production of CLT, most often, the wood of Silver birch (Betula pendula Roth.), Ash (Fraxinus excelsior L.), poplars (Populus spp.), Locust tree (Robinia pseudoacacia L.). This paper describes the suitability of cheap tulipwood (Liriodendron tulipifera L.) as a raw material for the production of CLT. Examples of the use of this type of panels in construction are also presented. The tulipwood has similar physical characteristics to softwood, for which CLT production technologies were previously developed. This makes it possible to use the technology previously for softwood CLT was developed. In addition, the tulipwood is characterized by aesthetic visual quality (wood surface similar to marble). Thanks to this, CLT boards to make exposed surfaces can be used.

Pneumologie ◽  
2004 ◽  
Vol 58 (11) ◽  
Author(s):  
S Kespohl ◽  
R Merget ◽  
M Gellert ◽  
T Brüning ◽  
M Raulf-Heimsoth

Author(s):  
V.V. Tanyukevich ◽  
◽  
S.V. Tyurin ◽  
D.V. Khmeleva ◽  
A.A. Kvasha ◽  
...  

Works on protective afforestation are carried out in order to protect agricultural land from degradation processes, as well as to improve the microclimate of land. The research purpose is to study the bioproductivity and environmental role of Robinia pseudoacacia L. forest shelterbelts in the conditions of the Kuban lowland. The approved and generally accepted methods of forest valuation, forest land reclamation, botany, and mathematical statistics were applied. Plantings were created according to the standard technology for the steppe zone of the Russian Federation. The area of forest shelterbelts is 62.4 ths ha, including 5 % of the young growth (I state class), 80 % of middle-aged forest plantings (II state class), 10 % of maturing plantings (II state class), 5 % of mature and overmature plantings (III state class). Living ground cover is formed by the following species: Koeleria pyramidata L., Poa pratensis L., Festuca pratensis H., Elytrígia repens L., Dactylis glomerata L., and Phlum pratense L. Aboveground phytomass is 100–300 g/m2; height is 25–32 cm. Plantings are characterized by the quality classes: young growth – I and II; middle-aged and maturing – III; mature and overmature – IV. At the age of natural maturity (70 years), the Robinia trunk reaches the average height of 15.1 m with the average diameter of 22.1 cm. The total stock of wood reaches 18, (ths m3), including (ths m3): young growth – 68 (ths m3); middleaged plantings – 14,871 (ths m3); maturing plantings – 2,187 (ths m3); mature and overmature plantings – 1,314 (ths m3). Aboveground phytomass in young growth is 20.2 t/ha; in mature and overmature plantings it is 391.2 t/ha. In the region it is estimated at 17,070 ths t, including (ths t): young growth – 64; middle-aged plantings – 13,753; maturing plantings – 2,032; mature and overmature plantings – 1,221. The share of stem mass reaches 84.5–80.8 %; woody greenery – 4.2–1.5 %; branches – 11.3–17.7 %. Recalculation coefficients of the stock into aboveground phytomass are the following for: young growth – 0.936; mature and overmature forest shelterbelts – 0.929. Phytosaturation of forest shelterbelts varies within 0.314–2.474 kg/m3. Forest shelterbelts have accumulated 8,534 ths t of carbon, which is estimated at 145.1 mln dollars. The sphere of application of the research results is the Krasnodar Krai forestry, which is recommended to create an additional 60 ths ha of forest shelterbelts, which will provide a normative protective forest cover of arable land of 5 % and annual carbon sequestration up to 3.4 t/ha.


Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 357
Author(s):  
Zhaohui Jia ◽  
Miaojing Meng ◽  
Chong Li ◽  
Bo Zhang ◽  
Lu Zhai ◽  
...  

Anthropogenic overexploitation poses significant threats to the ecosystems that surround mining sites, which also have tremendous negative impacts on human health and society safety. The technological capacity of the ecological restoration of mine sites is imminent, however, it remains a challenge to sustain the green restorative effects of ecological reconstruction. As a promising and environmentally friendly method, the use of microbial technologies to improve existing ecological restoration strategies have shown to be effective. Nonetheless, research into the mechanisms and influences of rock-solubilizing microbial inoculums on plant growth is negligible and the lack of this knowledge inhibits the broader application of this technology. We compared the effects of rock-solubilizing microbial inoculums on two plant species. The results revealed that rock-solubilizing microbial inoculums significantly increased the number of nodules and the total nodule volume of Robinia pseudoacacia L. but not of Lespedeza bicolor Turcz. The reason of the opposite reactions is possibly because the growth of R. pseudoacacia was significantly correlated with nodule formation, whereas L. bicolor’s growth index was more closely related to soil characteristics and if soil nitrogen content was sufficient to support its growth. Further, we found that soil sucrase activity contributed the most to the height of R. pseudoacacia, and the total volume of root nodules contributed most to its ground diameter and leaf area. Differently, we found a high contribution of total soil carbon to seedling height and ground diameter of L. bicolor, and the soil phosphatase activity contributed the most to the L. bicolor’ s leaf area. Our work suggests that the addition of rock-solubilizing microbial inoculums can enhance the supply capacity of soil nutrients and the ability of plants to take up nutrients for the promotion of plant growth. Altogether, our study provides technical support for the practical application of rock-solubilizing microbes on bare rock in the future.


1981 ◽  
Vol 36 (11-12) ◽  
pp. 916-920 ◽  
Author(s):  
Gary Kuroki ◽  
Jonathan E. Poulton

Abstract Crude extracts from young Robinia pseudoacacia seedlings, shoots, and callus tissue catalyze the para-O-methylation of apigenin to acacetin using S-adenosyl-ʟ-methionine as methyl donor. Optimum activity was exhibited at pH 9.0, and Mg2+ was not required for maximum activity. EDTA (10 mᴍ) did not affect the reaction rate, but 47% inhibition was observed with SAH (100 μᴍ). β-Mercaptoethanol (5 mᴍ) was required in the homogenization medium for optimum O-methyltransferase activity. Apigenin (Km, 50 μᴍ) was the best substrate, but significant activity was shown towards caffeic acid, 5-hydroxyferulic acid, naringenin, and quercetin. Paracoumaric, ferulic, and sinapic acids were not methylated. The Km for S-adenosyl-ʟ-methionine was 31 μᴍ. Our demonstration of a para-O-methyltransferase activity methylating apigenin, but not para-coumaric acid, strongly supports the conclusion that the B-ring methylation pattern of acacetin is determined at the C15-level in Robinia pseudoacacia.


2021 ◽  
Vol 13 (1) ◽  
pp. 174-194
Author(s):  
Dmitry K. Suchkov ◽  
Olga V. Ruleva

Волгоград относится к промышленным городам, где роль зеленых насаждений особенно важна для сохранения экологической ситуации и снижения пресса на экосистему города. Целью исследования являлась оценка лесокультурных ландшафтов урбанизированных территорий с применением ландшафтно-географического подхода на основе картографирования по дистанционным данным. Материалы и методы. Использовались цифровые крупномасштабные космоснимки Quick Bird  (М 1:4000 - 1:17000) с разрешением 0,6 м, топографические карты на город Волгоград (М 1:100000) и др. справочные материалы. Основным методом исследований послужило ландшафтно-экологическое профилирование ключевых участков. Закладка таксационных пробных площадей в насаждениях проводилась на основании общепринятых методик по лесной таксации и агролесомелиоративному устройству. Результаты исследования описывают данные экспликации земель на 2 ключевых участках, расположенных в Кировском районе Волгограда и основные морфологические признаки древостоя: № 1 в 200-250м к югу от поселка Горная Поляна. Общая площадь участка - 412,6 га. облесенность территории ключевого участка составляет 74,9%. Ключевой участок № 2 расположен к югу от балки Отрадная, на межбалочном водоразделе балок Отрадная и Капустная. Общая площадь участка составляет 304,1 га. облесенность ключевого участка № 2 составляет 54,3%. Заключение. Практически весь плакор на ключевом участке № 1 занят массивом из сосны обыкновенной (Pinus sylvestris L.) и робинии псевдоакации (Robinia pseudoacacia L.), именно им обусловлен высокий показатель лесистости плакорного яруса. Высокая лесистость гидрографической сети (84 %) обусловлена естественным древесным массивом, сохранившимся в балке Отрадной. На ключевом участке № 2 показатели лесистости во всех ландшафтных полосах не превышают 70%.


2019 ◽  
Vol 25 (1-2) ◽  
Author(s):  
Zs. Keserű ◽  
K. Rédei ◽  
J. Rásó ◽  
T. Kiss

Black locust (Robinia pseudoacacia L.) is a valuable stand-forming tree species introduced to Europe approximately 400 years ago from North America. Today it is widely planted throughout the world, first of all for wood production. In Hungary, where black locust has great importance in the forest management, it is mainly propagated by seeds. But since the seed-raised plants present a great genetic variation, this type of propagation can not be used for Robinia’s improved cultivars. In the Hungarian black locust clonal forestry, propagation from root cuttings can be used for reproduction of superior individuals or cultivars in large quantities. However, this method demands more care than raising seedlings from seeds and can be applied with success in well-equipped nurseries.


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