Advances in Bamboo Science最新文献

India has the second richest diversity of bamboos, with a wide variety of indigenous and exotic bamboo species. They are found in and around forest and non-forest areas and have immense socioeconomic, cultural, and ecological significance. The various uses of bamboo mean that it is an important non-timber forest product that has multiple roles in the maintenance, development and protection of the environment. The Himalayan region has untapped bamboo resource potential; and this study reviews the existing literature. It is supported by research experience on the bamboo resources of the western Himalaya region of India (mainly focused on distribution, utilization and marketing). The western Himalayas have 14 bamboo species with a scattered to moderate distribution in Uttarakhand and Himachal Pradesh. Jammu and Kashmir have low bamboo diversity. A survey of the major markets in the western Himalaya revealed that there is a wide range of useful and decorative bamboo products available in the market. Bamboo is an important resource in western Himalaya and an increase in bamboo cultivation and its use could help boost livelihoods while providing a number of environmental benefits.

Bamboo continues to attract attention globally as a sustainable material and is used in many applications. However, the quality of bamboo products in Uganda remains poor and cannot compete in the local and international markets. Bamboo's low product quality is associated with poor raw material processing and limited preservation methods, which lead to the short service life of the products due to its susceptibility to bio-deterioration and degradation. To cope with the above, artisans in Uganda apply various preservation methods depending on their knowledge and available resources. In this paper, the authors seek to determine the methods used by the artisans to preserve bamboo, understand the background of their intention to preserve, and their perception towards bamboo preservation. The Theory of Planned Behaviour was used as the main framework to understand artisans' perceptions towards the intention to preserve bamboo. A cross-sectional survey with 186 randomly selected artisans working with bamboo was conducted across three agroecological zones presumed to be Uganda's main bamboo growing areas. The study reported 13 available bamboo species, with the artisans exploiting mainly three of these species. Most artisans (86%) were aware of the need to preserve bamboo, with 67.4% practising bamboo preservation. The artisans use different methods and chemicals for preservation, i.e. leaching (17%), smoking (14%), soaking in crude lake salt (31%), boric acid and borax solutions (20%), surface application (16%), and pressure treatment (1%). Ordinal logistic regression was used to model artisans’ intention to engage in bamboo preservation. Attitude and subjective norms were the psychological factors that significantly influenced artisans’ intention to preserve bamboo. Interventions that increase benefits accrued from preserved bamboo can improve artisans’ attitude and subjective norms and enhance their intention to engage in bamboo preservation.

As bamboo composites have wide applications, this study investigated the mechanical properties (tensile and flexural) of oil-treated Ethiopian Highland bamboo fibre/polyester laminated composites using an experimental and analytical approach. The goal of oil treatment is to soften the components of bamboo fibre, resulting in more flexible fibre strands with high tensile and flexural strengths. The composite was manufactured using hand layup methods with a fibre/matrix ratio of 35%/ 65% by volume. The fibre orientations used in the laminates were [0]₅ for both tensile and bending tests. The maximum tensile and flexural stresses of oil-treated bamboo fibre-reinforced polyester composite (OBFP) were 193.3 MPa and 173.4 MPa, respectively. These outcomes surpassed untreated bamboo fibre-reinforced polyester composites by 39.6% and 50.2% (UBFP), respectively. The fibre tensile and flexural strains were increased by 25.1% and 25.7%, respectively, as a result of oil treatment. According to the findings, oil-treated bamboo fibre laminates exhibited better tensile and flexural characteristics. The oil treatment lubricated the fibre and increased strand flexibility to reduce abrupt breakage.

Species belonging to the genus Ochlandra Thwaites, the reed bamboos, play a significant role in sustaining the ecology of forests and the livelihood of rural communities in the Western Ghats. Karyology of this predominantly endemic genus of the region is poorly understood. Of the ten species belonging to the genus, chromosomal information is known for only two species. We studied mitotic and/or meiotic chromosomes of eight species, using squash and smear techniques. We report chromosome number (2n) of six species for the first time and two additional 2n reports of a previously studied species, O. travancorica (Bedd.) Gamble. The species and their chromosome numbers are: O. keralensis M. Kumar, Remesh & Sequiera and O. spirostylis M. Kumar, K. K. Seethal. & Sequiera (2n = 48), O. ebracteata Raizada & Chatterji (2n = 64), O. beddomei Gamble and O. setigera Gamble (n = 36, 2n = 72), O. scriptoria (Dennst.) C. E. C. Fisch. (2n = 72), O. wightii (Munro) C. E. C. Fisch. (n = 36, 2n = 60, 72) and O. travancorica (n = 24, 2n = 48, 72, 96). The basic chromosome number of the genus is x = 12. The somatic chromosomes of all studied Ochlandra species are small in size, with a length ranging from 0.45 to 2.50 µm. The present study has provided new perceptions on speciation, evolution and taxonomy of the genus and indicates that the taxonomic muddle in O. travancorica is due to intraspecific genetic variability as evident by chromosomal numerical variation and polyploidy.

Bamboo is a widely available bio-resource that is considered as a sustainable and eco-friendly raw material for fabricating composites that could replace timber and timber-based products. Several structural bamboo composites (SBCs) have been developed as a sustainable alternative to traditional load-bearing materials in different applications. These composites utilise bamboo in its converted forms viz., strips or strands, bonded with structural grade polymeric adhesives, and compacted and cured under pressure and at high temperature, forming thick panels or beams with standardized cross-sections. With recent advances in processing technologies, several interventions have been undertaken to improve the production efficiency and overall properties and performance of SBCs. While the properties of these composites are comparable or even better than those of commonly used wood and wood-based mass timber products, their performance is strongly influenced by the different processing parameters used in their fabrication. This article presents a comprehensive overview of the recent literature about the production process of SBCs and their physico-mechanical and other properties, factors affecting these quality parameters and current developments in processing technologies. It also examines potential applications and the future scope of research work in this area.

Glued-laminated bamboo (GLB) is an engineered material affected by the quality and uniformity of its constituent feedstock bamboo materials as well as by the assembly of this feedstock in the manufacturing process. A review of issues affecting the fabrication of GLB, including material properties, orientation of strips in GLB products, variation in glueline quality and prevalence of nodes, is presented. The potential impacts on the variability of GLB products are described. A number of recommendations for the engineered bamboo manufacturing industry are proposed.

Fast-growing forest species with multiple uses, like bamboo, have aroused interest for their silvicultural applications. Bamboo species are a valuable source of renewable raw material, and Bambusa vulgaris is an economically important species. However, there are limitations to large-scale cloning of adult-selected genotypes. This study aimed to evaluate the in vitro cloning of Bambusa vulgaris in different culture systems, sucrose and activated charcoal supplementation by the inter-simple-sequence repeat (ISSR) molecular markers. In vitro bud multiplication and shoot elongation were evaluated in three cultivation systems: semi-solid and liquid culture media, and temporary immersion bioreactor (TIB). The sucrose concentrations, 0 and 30 g L⁻¹ were evaluated in the stages. Both the culture media were supplemented with 2.0 mg L⁻¹ benzylaminopurine (BAP) and 0.5 mg L⁻¹ α-naphthalene acetic acid (NAA). The absence and presence of activated charcoal (100 mg L⁻¹) were evaluated in the in vitro rooting. MS culture medium was supplemented with 2 mg L⁻¹ indole-3-butyric acid (IBA), 1.0 mg L⁻¹ NAA, and 0.5 mg L⁻¹ BAP. Semi-solid culture medium supplemented with 30 g L⁻¹ of sucrose presented superior emission of bud per explant. Liquid culture medium supplemented with 30 g L⁻¹ of sucrose presented the most elongated shoots. Activated charcoal in the culture medium did not influence the adventitious rooting. Micropropagated plants showed genetic fidelity and were clones of the adult selected plant.

Bamboo has many potential applications in agroforestry systems. This study evaluated the photosynthetic active solar radiation available (PAR) to intercrops in three bamboo species as a function of estimated soil water content in the Brazilian savanna biome (tropical savanna climate with dry winters and rainy summers). The study was conducted from 2019 to 2021 (three to five years after planting), with clumps spaced at 8 × 5 m. PAR was measured below the bamboo at 0900, 1200, and 1500 h in the central, in-row, and inter-row positions. The estimated soil water balance was used to define the water available in the soil, which was correlated with the fraction of available PAR. The lowest value for the available PAR fraction occurred at the end of the maximum soil water content, being lower than 0.20 for Dendrocalamus asper and Dendrocalamus strictus and 0.80 for Guadua angustifolia. D. asper and D. strictus showed an inverse response rate of 0.50% and 0.75%, respectively, in the change in the available PAR fraction for each percentage change in the estimated mean soil water content 60 days prior to the PAR measurement date. G. angustifolia did not show any significant effect because of the smaller size of the culms and clump. The available PAR was correlated with estimated soil water content and species rate response. This information can be used to plan the cutting of bamboo culms to maximize the amount of PAR based on intercrop demand.

While the spatial distribution of bamboos may substantially affect the quality of giant panda habitats, no attempts have been made to examine the spatial pattern of bamboos at small scales. We analyzed small-scale spatial patterns of two bamboos, Bashania fargesii and Fargesia qinlingensis, that are grazed by the giant panda (Ailuropoda melanoleuca) in the Qinling Mountains, China. The analysis used univariate and bivariate Ripley’s K function, and geostatistics. Culms (live and dead) and live shoots were aggregately or randomly distributed in space with aggregation repeated. The mortality pattern of F. qinlingensis was aggregated throughout the entire study scale (0–5 m), while the mortality pattern of B. fargesii was aggregated at smaller scales< 1.3 m. The size class distribution showed more medium-sized dead culms of B. fargesii and F. qinlingensis than expected, suggesting ramet survivorship was size-dependent. The shoot distribution in space either resulted from the characteristics of clonal growth or resource limitation. Both clonal habit and resource limitation drove the observed shoot distribution pattern in F. qinlingensis throughout the entire study scale, while clonal growth was likely responsible for the shoot regeneration pattern in B. fargesii at smaller scales. A positive relationship was observed between live culms and the number of dead culms in B. fargesii and F. qinlingensis, implying the importance of intraspecific competition for resources among culms. However, a negative relationship was found between the average basal diameter and culm density in B. fargesii and F. qinlingensis, indicating density-dependent mortality among culms. Variograms revealed spatially explicit structures of culms and new shoots, and revealed repeated patterns in space. These findings imply that intraspecific competition and clonal growth habit in heterogeneous microenvironments in space generated the spatial pattern of F. qinlingensis and B. fargesii. We further concluded that the quality of giant panda habitats varied in space, based on size class distribution and spatial patterns, implying that giant panda habitat may be over-estimated.

Given the hygroscopic nature of bamboo and its reduction in strength with increasing moisture content, we evaluated the effects of hornification – generated through the application of drying and rewetting cycles – on the physical, mechanical, and chemical properties of the culms of Dendrocalamus asper. Our objective was to assess if the treatment would cause a reduction in water uptake, an increase in the dimensional stability of bamboo, and a stiffening of the material, increasing its mechanical strength. Specimens were submitted to a maximum of 15 cycles, being immersed at room temperature (22 ± 3 °C) and dried at 50 ± 5 °C. Absorption capacity, dimensional stability, density as measured with a helium pycnometer, tensile tests, scanning electron microscopy (SEM) analysis, X-ray diffractometer (XRD) and Fourier-transform infrared spectroscopy (FT-IR) were undertaken. Hornification increased the dimensional stability of bamboo proportionally to the number of cycles applied, and a 5.8 % increase in cross section was seen after 264 h for 15 cycles. The control samples increased by 17.8 %. Reduction in the water absorption was not verified for treated bamboo. The elastic modulus was maintained and the tensile strength after treatment was reduced (258.6 MPa for control and 207.5 MPa after 15 cycles). Chemical analysis and microscopy did not show any significant changes in the composition of the bamboo after the application of wetting and drying cycles.