Advances in Bamboo Science最新文献

Bamboo is an ideal plant for commercial production due to its rapid growth rate, high biomass production, low cost of production and environmental friendliness. Although Ethiopia has the highest bamboo cover in Africa, allometric equations for estimating its biomass are scarce. Most allometric models developed to date have been largely concerned with trees and shrubs. The objective of this study was to generate species- and site-specific allometric models that could be used to estimate the total aboveground dry biomass and culm dry biomass of lowland bamboo in northwest Ethiopia. Three power form-based allometric models were created using diameter at breast height (DBH) and culm height (H) as independent variables. One hundred and eight Oxytenathera abyssinica culms were used to predict the total aboveground biomass and culm biomass. Model one (M1) was the best model to predict the culm and total aboveground biomass of the species, regardless of forest type. The allometric models may provide useful information about aboveground biomass and culm biomass estimation methods to forestry professionals, bamboo producers and other stakeholders, and could help in the calculation of the country’s contribution to global carbon sequestration and trade.

This study investigates the influence of elastic properties and nodes on the flexural behaviour of bamboo culms by comparing different characterization techniques and theoretical approaches. The most representative parts of the bamboo culm were selected using microscopic images of bamboo cross-sections. These were sliced from the bottom, middle, and top parts of a single culm and were analyzed with Digital Image Processing. Four-point bending tests were conducted on twelve culms of Phyllostachys aurea, subdivided into groups of untreated (UN) and heat-treated (HT) samples. The axial modulus of elasticity (E_b) and the shear modulus (G) were determined experimentally using four different mathematical models: (i) a global deflection model using the Euler-Bernoulli beam theory according to the ISO Standard; (ii) a global deflection model using the Timoshenko beam theory; (iii) a global deflection model based on the Timoshenko beam theory but accounting for the presence of nodes; and finally, (iv) a local model using extensometry. The dominant failure modes for UN and HT samples are described and discussed, and were influenced by the moisture content (MC). Approaches (i) and (ii) showed good agreement, giving reliable parameters to assess E_b. The third approach (iii) indicated that the nodes significantly influence the flexural behaviour of the culms. Approach (iv) was appropriate for determining G, but resulted in higher values of E_b, typically not representative of the material.

The primary aim of this research was to study the manufacturing process of bamboo charcoal briquettes following the principles of life cycle assessment. Charcoal briquettes produced from lowland bamboo exhibited good fuel characteristics, higher calorific value and fixed carbon, and low moisture content. The ash content was in compliance with the international acceptable standard. Bamboo charcoal briquettes from highland bamboo (Oldeania alpina) and lowland bamboo (Oxytenanthera abyssinica) had calorific values of 6785 cal/gm and 7106 cal/gm, respectively. Manufacturing the briquettes at an ideal moisture content for carbonization saves time and leads to a maximum yield. Bamboo bioenergy (briquettes) produced in regulated kilns using locally available materials have gained popularity. Bamboo biomass utilization contributes to reducing deforestation and creates employment opportunities in bamboo value chains, as well as and contributing to UN SDG 7. Developing sustainable bamboo biomass energy use requires informing entrepreneurs about suitable business ecosystems. This research should encourage the proper utilization of the biomass feedstock and should ensure a healthier environment through the supply of a renewable source of energy. The most relevant findings in the present work were the production of environmentally friendly charcoal briquettes and their characterization (proximate and calorific value analysis) within the context of life cycle assessment of bamboo charcoal briquette technology.

The disposal of bamboo processing residues and spent tea leaves is an environmental concern, but their reuse as compost can be not only reduce the amount of waste, but can also convert the waste products into valuable resources that provide nutrients to crops and improve soil fertility. Combining bamboo, with its high C/N ratio, and tea leaves with high nitrogen content may produce high quality compost, but its effect on composting rate and nutrient content is unclear. This study evaluated the effect that co-composting of bamboo powder and tea leaves has on composting rate and quality. Three compost types were prepared: B100 (600 kg bamboo powder), B40 (240 kg bamboo powder and 360 kg tea leaves), and B20 (120 kg bamboo powder and 480 kg tea leaves), with two replicates each. The mixed materials were allowed to compost in an outdoor compost shed for 98 d. Peak composting temperatures occurred later for B40 and B20 than for B100, suggesting that the microbial activity of the co-composts may have been reduced during the early composting stage. However, the C/N ratio, NH₄⁺/NO₃⁻ ratio, chemical oxygen demand (measured in hot water extracts), and juvenile plant growth experiments using komatsuna (Brassica rapa var. perviridis) revealed that the composting rate was higher in B20 than in B40 and B100. Additionally, at the end of the composting period, B20 had a C/N ratio of approximately 10 along with high total nitrogen and NO₃⁻-N content, indicating an improved compost quality for use as a fertilizer.

O. abyssinica, known in Ethiopia as lowland bamboo, is a solid-stemmed clump-forming bamboo species widely distributed in the western dry regions of Ethiopia. The versatility of the species means that it has enormous potential for land restoration in arid and semi-arid areas, in addition to bringing socio-economic benefits. It also displays remarkable adaptability, allowing it to thrive in the challenging ecological conditions of areas such as the Abay Gorge. The Abay Gorge, situated within the Upper Blue Nile River Basin of Northwestern Ethiopia is characterized by problems associated with soil erosion and land degradation. This study, therefore, aimed to evaluate and recommend a suitable spatial analysis for the adoption and development of lowland bamboo (O. abyssinica). Fifteen primary influencing factors were chosen according to the needs of O. abyssinica, the accessibility of data, and the financial implications associated with data analysis, particularly the expenses related to soil laboratory testing. Eight composite soil samples were taken directly by dividing the watershed into two categories (upper and lower catchment areas). These composite soil samples were analyzed. Data analysis was performed via Analytical Hierarchy Process (AHP) in conjunction with Multi-Criteria Decision-Making (MCDM) analysis and the use of Remote Sensing (RS) and Geographic Information System (GIS). The spatial analysis employed in this study was a weighted sum overlay analysis, which was applied by considering the criteria weight assigned to each factor. The analysis revealed that 21.2 % (666.5 ha) of the total area was highly suitable for the growth and development of O. abyssinica. About 56 % (1753 ha) of the land was moderately and marginally suitable for the desired land utilization type. However, 23 % (723.8 ha) of the study area was unsuitable for O. abyssinica. O. abyssinica has the potential to rehabilitate large parts of challenging areas such as the Abay Gorge due to its naturally invase rhizomes and drought-tolerance. It can also be introduced into agroforestry systems and used as living fences for villages.

This study clarified the functional characteristics of microorganisms during the co-composting of bamboo powder and tea leaves. Three treatments were established for 14 weeks of composting: B100 (600 kg bamboo powder), B40 (240 kg bamboo powder and 360 kg tea leaves), and B20 (120 kg bamboo powder and 480 kg tea leaves), with two replicates each. The functional characteristics of the microorganisms were analyzed using a BIOLOG EcoPlate for carbon substrate utilization patterns using kinetic parameters, microbial diversity analysis by calculating diversity indices, and microbial community structure analysis via principal component analysis of kinetic parameters. When bamboo powder was composted alone, the microbial diversity was high in the early composting stage because of the utilization of the rich and complicated carbon substrates. However, in the late composting stage, the microbial diversity was low because of the utilization of poor and simple carbon substrates. In contrast, when bamboo powder and tea leaves were combined, carbon substrate utilization and microbial diversity were low during the early composting stage. In the middle and late stages of composting, abundant carbon substrates became available, and microbial diversity increased. Differences in carbon substrate utilization patterns can be separated by microbial community structure analysis, especially at the end of composting. The communities were divided according to the proportions of bamboo powder and tea leaves. In the early stage of co-composting bamboo powder and tea leaves, microbial activity decreased because of the lower compost temperature and higher tea polyphenol content. However, in the middle and late stages, microbial activity may increase owing to the supply of tea-derived soluble sugars and amino acids. The co-composting of bamboo powder and tea leaves may enhance microbial activity, diversity, and carbon substrate utilization during the middle and late composting stages.

Economical CO₂ adsorbents are gaining significant attention as viable solutions to combat climate change. This research assessed the CO₂ adsorption potential of solid residues following the gasification of bagasse (SR-Bagasse), bamboo (SR-Bamboo), and rice husk (SR-Rice husk) in various systems in Vietnam and Cambodia. Among these residues, SR-Bagasse showed the highest CO₂ adsorption capacity, followed by SR-Bamboo, while SR-Rice husk exhibited moderate performance. The CO₂ adsorption capacity at 25 °C with 100 % CO₂ flow varied from 6 % to 9.5 % of the adsorbent's weight. Under flue gas conditions (15 % CO₂ and 85 % N₂), the adsorption capacity ranged from 2 % to 5 %. Additionally, these chars demonstrated significant recyclability with 90 % of initial adsorption capacity retained after 30 cycles, making them comparable to several advanced CO₂ adsorbents studied previously. The highest performance of SR-Bagasse could be attributed to its substantial microporous and ultra-microporous volumes, with micropores serving as both CO₂ adsorption sites and conduits to ultra-micropores. This study's findings emphasize the potential for integrating energy production with the development of economical and scalable CO₂ adsorbents for industrial use.

Chimonocalamus griffithianus is a socio-economically important hill bamboo growing in the north-eastern states of India that flower gregariously. It is important to record the flowering episodes of populations so that post-flowering conservation and management can be guided. This study records flowering in a population of C. griffithianus from Nokrek National Park, West Garo Hills (Meghalaya, India). We observed a gregarious flowering followed by the mortality of entire clumps and sparse germination. By scrutinizing earlier flowering records from different populations, we found that flowering episodes have not been synchronized among populations, with different populations flowering at different times. Consequently, the development of a database and recording the flowering of different populations could be very important for post flowering conservation and management of the species, and the conservation methods could further be strengthened by incorporating information related to genetic diversity and population genetic structure.

Bamboos are naturally fast-growing species in tropical and non-tropical regions, with some species growing more than 1 m per day. Oxytenanthera abyssinica is an important bamboo species that could help meet current and future needs worldwide. This study was designed to assess the effects of harvesting techniques and intensities on sustainable utilization of O. abyssinica. Clumps that had a similar number culms were used to conduct the experiment. A factorial experiment with two harvesting techniques (X-shape and Horse-shoe shape) and five levels of harvesting intensities (25, 50, 75, 100 and 0 % harvesting of mature culms) was conducted for five successive years in the dry season. Sprouted and dead shoots, recruited culms, and mean culm diameter at breast height were recorded. Data were analysed using two-way-ANOVA. Culm/shoot sprouting had significantly different values with harvesting techniques; the X-shape harvesting technique produced a higher number culms than horse-shoe harvesting technique. Interaction effects between harvesting techniques and harvesting intensities on shoot sprouting, culm recruitment and shoot abortion were not observed. Both harvesting techniques and intensities had a significant effect on mean culm diameter; i.e., 25 % and 75 % of the mature culms harvested under the X-shape and horse-shoe harvesting techniques, respectively, produced thicker bamboo culms than the unharvested clump (control). Culm recruitment decreased in the second year, and then increased in the third year, subsequently showed a decreasing trend for all treatments. This may have been related to repeated culm harvesting. The population structure has also varied with harvesting technique and intensity. To utilize this species sustainably, the species may need a specific cutting cycle. This study suggests the need for further study through incorporating cutting cycles with different levels of harvesting intensity to develop a sustainable management method.