Advances in Bamboo Science最新文献

Oldeania alpina (highland) and Oxytenanthera abyssinica (lowland) bamboo are two indigenous bamboo species and are vigorous in highland and lowland agro-ecologies, respectively. They have enormous socioeconomic, ecological, and traditional roles in the community. We address bamboo plantations and their distribution, identify factors influencing bamboo planting and marketing, and assess the role of bamboo for smallholder farmers and customers in Ethiopia. We also examine planting and management practices, governance, and challenges and opportunities for bamboo production and marketing. The decisions to plant bamboo are influenced by many demographic and socioeconomic factors, such as age, educational status, family size, income, farm size, land scarcity, bamboo culm price, and market information. They are also influenced by institutional factors, including market distance, marketing linkages, access to markets, tenure security, and psychological factors such as the perception of risk and attitude towards bamboo production. Bamboo plays a variety of socio-economic, ecological, and traditional roles in the community. It is one of the essential components of agricultural tasks and practices for most households and provides considerable cash income. For instance, it provides material for house and fence construction, furniture, wood fuel, and musical instruments. It is used as a source of food, medicine, and fodder and also for soil and water conservation, biodiversity functioning, and mitigating global climate change, as well as an alternative source of timber and non-timber products for rural and urban people, forest industries, construction, and energy sectors. Despite this, its significance has been affected by deforestation and degradation, overexploitation, increased agricultural investment, and social issues. Although there is a positive policy environment, there is still a lack of coordination, overlap of roles and responsibilities, and limited dedicated manpower and resources in the bamboo sector, as well as limited government support for the value chain development of the sector. Creating an enabling market environment and constructing a value chain are critical for the development of the sector. Furthermore, the selection of higher-quality bamboo landraces, extension support, and the local application of the established regulations are all critical.

It is increasingly important to explore means of reducing deforestation in our environment by sourcing alternatives for timber in the forest. Bamboo (Bambusa vulgaris) is known for its strength and flexibility, which makes it a popular material for construction, furniture, and other uses that are still being explored. This paper evaluated the use of bamboo for the design of ceiling boards based on the physical and mechanical properties of bamboo. We explored the use of bamboo powder, bamboo fibre, and bamboo sticks that are usually discarded during construction activities, using urea-formaldehyde as a binding agent. The bamboo ceiling boards were tested for their physical (water absorption, thickness swelling, and density) and mechanical (modulus of rupture and modulus of elasticity) properties. Water absorption ranged from 41.9% to 86.4% after 2 h immersion in water and from 41.9% to 97.6% after 24hrs immersion. The modulus of rupture was 78.915 N/mm² and the highest density was 0.424 g/cm³. Given these results, bamboo is a suitable material for the production of ceiling boards.

With bamboo’s rapid renewability, short rotation period, versatility, and good mechanical properties, engineered bamboo composites have undergone significant evolution. This paper examines the recent changes in bamboo product manufacturing, starting with a wholistic classification of culm breakdown to the plethora of different constituent elements: full culm, flattened bamboo, bamboo bundles, splits/strips, mats/curtains, and strands. Highly cracked flattened strips used in bamboo scrimber are 4–5 times greater in specific surface area than crack-free strips, requiring an estimated 6–10 times higher resin consumption than laminated bamboo. Based on their structure, bamboo composites can be classified into three categories: 1) lamination of minimally modified culms, 2) laminated mat structures with controlled or semi-random placement of constituent elements and 3) random mat structures composed of thin bamboo strands. Composite formation is transitioning from random placement of large, thick strips to more controlled layup with secondary elements of stitched strip curtains, helping minimize edge-to-edge strip overlaps and improve bonding efficiency with less mat compaction. Density-structure-strength property relationships are also compared between various engineered bamboo and common engineered wood products. Other technical advancements include crack-free flattened bamboo and hybrid bamboo-wood products.

This study assessed the drying behaviour of young and mature Bambusa vulgaris culms and evaluated their utilisation potential. Two and four-year old Bambusa vulgaris culms were harvested and prepared to the required length of 21 internodes. The first seven internodes were taken as the bottom, the second seven were taken as middle and the last seven internodes were taken as the top. The study used samples from the bottom and top. Physical properties, including basic density and moisture content, were determined in accordance with ISO 13061–2 (ISO 2014) and EN 13183–1 (EN 2002), respectively, while shrinkage properties (radial, tangential, longitudinal and volumetric) were determined following established procedures. For the bottom and top portions of the mature bamboo after 18 days of drying, radial shrinkage values were 3.31% and 5.01%, tangential values were 4.95% and 5.78%, and longitudinal values were 0.28% and 0.35%, respectively. For the bottom and top portion of two-year-old culms, the values were 15.0% and 18.6% for radial shrinkage, 20.5% and 25.8% for tangential shrinkage and 0.46% and 0.47% for longitudinal shrinkage, respectively. The tangential shrinkage values were higher than the radial and longitudinal shrinkage values. The moisture content of the bottom part of the mature bamboo culm after 3 and 18 days of drying were 31.4% and 12.2%, while the young culms had values of 53.5% and 27.8%, respectively. Mature bamboo culms had better drying behaviour than young culms. Consequently, mature bamboo culms are more suitable for use in engineered composite materials.

Bamboo is an important non-timber forest resource with multiple uses across many different sectors. It has many economic, social, and ecological roles and is seen as a key to reducing poverty in some regions because of its value to local communities and industry. Bamboo is a plentiful resource in Ethiopia, although it is underutilized. The primary goal of this study was to investigate the factors that influence the utilization of bamboo by processors. A questionnaire survey was used to investigate the effects of the awareness levels of processors, market demand, financial capacity, technical accessibility, supporting markets, and market linkages on the levels of utilization by processors, as measured by the variety of bamboo products. The data were collected from bamboo processors using a questionnaire administered by trained data collectors in Bahir Dar and Injibara and were analysed using ordinal logistic regression with the SPSS 20 software package. Access to technology, supporting markets, processors' awareness, and financial capacity were statistically significant determinants that positively affected the utilization of bamboo, but market demand and market linkages were not. We recommend that government at all levels provide policy-based support and attention, either financially or in other ways, and that responsible agencies such as Technique, Vocational and Enterprise Development Centres, Micro and Small Enterprise Offices, Trading and Agricultural Bureaus cooperating with the federal government, and the International Network of Bamboo and Rattan (INBAR) should prepare manuals, videos, leaflets, skill-oriented training, and experience-sharing programmes. Future research should expand on the current study by including more variables on expanded targets and using other models that consider the interaction effects of independent variables. They should also conduct comparative studies of bamboo utilization levels among different bamboo processors in different regions of Ethiopia.

Water leaching is a traditional bamboo treatment method in which fresh bamboo poles are immersed in running water for at least 30 days to leach out water-soluble substances such as starch and carbohydrates. This method is easy to apply and does not require additional chemicals. Although water leaching is widely applied, its influence on the physical, mechanical, and chemical properties of bamboo and its effect on the durability of bamboo against termites has not been fully explored through experimental methods. This paper assesses the effects of water leaching treatment on bamboo and identifies the potential and limitations of this treatment. A 23% reduction in the density of bamboo after water treatment was found, which can be related to the removal of water-soluble extractives from the material. A significant (15%) increase in the modulus of rupture and a 20% increase in the modulus of elasticity were identified using a three-point bending test after water treatment while keeping a similar fibre volume fraction. Water leached bamboo had less dimensional stability and higher water absorption than untreated bamboo. As the density of the bamboo decreased, more space became available in its bundles for water. A darkened surface was observed after treatment, but no chemical modifications were found through FT-IR spectroscopy. Termites can use cellulose as a source of food, and the removal of starch from bamboo did not improve its resistance against this insect. On the contrary, the free space created after treatment favoured the action of the termites, leading to a higher mass loss percentage for treated bamboo. The water leaching system should not be used as the only treatment method in bamboo being utilized for structural purposes, and the reduction of dimensional stability and the darkened surface must be considered when using the bamboo for furniture and handicraft applications.

In this work, the effect of densification and the maintenance of the outer skin on the flexural properties and thermal conductivity of Dendrocalamus asper Backer ex K.Heyne bamboo was investigated. The results showed improvements in bending resistance for the densified samples compared to the un-densified bamboo. Densified samples with the outer skin showed the highest bending strength. Samples with the outer culm wall in compression offered the best results, with an average modulus of rupture (MOR) of around 348.9 MPa and modulus of elasticity (MOE) of 28.4 GPa. These values are around 40% and 86% (MOR), and 17% and 30% (MOE) higher compared to densified samples without the skin and un-densified samples, respectively. The fracture sections of specimens after bending tests were analyzed using Scanning Electron Microscopy (SEM) to visualize crack propagation within the outer skin and bamboo tissues. Maintaining the skin increases the thermal conductivity, and the densified bamboo with the skin has a thermal conductivity of around 0.23 W/m.K, 12.8% higher than the densified bamboo without skin and 22.5% higher than un-densified bamboo. Although a reduction in thermal performance was achieved, it was concluded that is reasonable to keep the bamboo skin, as it improves the overall mechanical resistance and reduces material loss during bamboo processing.

In Ethiopia, bamboo thickets and woodlands play an important role in soil-water conservation and climate change mitigation in arid and semi-arid regions. However, bamboo mass flowering, rapid demographic changes and expansion of agricultural investments into bamboo dominated areas have led to deforestation and land degradation. This study assessed the effects of deforestation and subsequent cultivation on soil physical and chemical properties along a chronosequence of closely located agricultural lands with different times (1, 3, 5 and 7 years) since conversion from natural lowland bamboo forest. Soil samples (n = 90) were taken from both natural bamboo forests and adjacent agricultural lands at two soil depths (0–20 cm and 20–40 cm). Cation exchange capacity (CEC), K⁺, Ca²⁺, Mg²⁺ and available P varied significantly among cultivation periods and soil depth, while soil pH and Na⁺ varied with soil depth (P < 0.001). Soil C and total N contents (g/kg) in the 0–20 cm soil layer declined significantly and exponentially with increasing years under cultivation. Conversion of natural bamboo forest to cropland during the past seven-year period significantly increased soil pH with soil depth, while CEC declined throughout the cultivation period and with soil depth. In general, the results revealed that conversion of natural lowland bamboo forest and subsequent cultivation of the soil had negative effects on the measured soil physico-chemical properties.

_{A new bamboo species, quite widely distributed along the border between Sikka and East Flores Districts} on Flores, Indonesia, is described and illustrated. It is named in honour of Ir Joko Widodo, the President of Indonesia. The main distinction between this and other Fimbribambusa Widjaja species is the culm sheath auricle, which is long, glabrous and black, the linear sheath blade on the culms, the yellowish base to the leaves, the small leaf sheath auricle and long bristle, and the entire ligule.

Bamboos occur throughout much of the temperate and tropical world, have rapid growth, and have various commercial and environmental applications. Clonal production of selected plants on a industrial scale is an important strategy for the bamboo sector. This study aimed to evaluate the effects of the light spectrum on in vitro multiplication, elongation, adventitious rooting, and anatomical features of the leaf surface of Bambusa vulgaris. In the multiplication and elongation stages, in vitro–established explants were transferred to a culture medium supplemented with 8.88 µmol of 6-benzylaminopurine (BAP) and 2.69 µmol of α-naphthalene acetic acid (NAA), and subjected to four light spectra (i.e., white, blue, green, and red). At the adventitious rooting stage, the culture medium was supplemented with 9.84 µmol of indole-3-butyric acid (IBA), 5.37 µmol NAA, and 2.22 µmol BAP under identical light spectra. Explant survival was not influenced by light spectra in the multiplication and elongation stages. White (2.2 shoots) and blue (1.8 shoots) light spectra were the most suitable for the number of shoots per explant. The white spectrum was associated with the highest average length of shoots (7.4 cm) and number of leaves per explant (3.0 leaves). The white light spectrum resulted in the highest average chlorophyll a contents (12.60 µg mg⁻¹), total chlorophyll (16.60 µg mg⁻¹), and carotenoids (10.10 µg mg⁻¹). White and blue light spectra resulted in the best responses for vigor, and least senescence and tissue oxidation. White and blue light spectra favored the chlorophyll b content, resulting in 4.60 and 3.60 µg mg⁻¹, respectively. Survival (80.0 %), adventitious rooting (50.0 %), vigor, senescence, and tissue oxidation were favored in the white light spectrum in the adventitious rooting stage. Scanning electron microscopy of leaves exposed to the white light spectrum revealed microtrichomes and spines on the adaxial surface of the leaf blade, papillae and stomata; on the abaxial surface, there were many unicellular trichomes arranged in rows, denoting normal growth and development. These results may help the production of micropropagated plants of Bambusa vulgaris on an industrial scale.