2022 Vol. 41, No. 2

Display Method:
Research Prospect of Arched Specification Bamboo Materials for Building
SUN Feng-bo, FEI Ben-hua, QIN Dao-chun, HUO Chang-qing, WANG Xue-hua
2022, 41(2): 1-6. doi: 10.12390/jbr2022061
Abstract(327) PDF(56)
Abstract:
Bamboo is a high-quality engineering structural material.Bamboo arches are widely used in round bamboo buildings as the main force-bearing components,which not only have strong bearing capacity,are not easily deformed,are natural and environmentally friendly,and have good air permeability,but also enrich the design language of bamboo buildings.They present various forms,such as domes,beam-column frames,truss grids,woven structures,etc.,which boast extremely high artistic and practical value.At present,the processing technology of arched round bamboo mainly relies on fire roasting to soften and shape,which can hardly be industrialized because of the low production efficiency and the inaccuracies of the performance parameters.Hence,it cannot meet the needs of bamboo architectural design and industrial scale development,which limits the application and popularization of round bamboo.Therefore,it is imperative to establish and improve the mechanized production process,specified product system and standardized performance evaluation system,and guide the technical upgrading,standard formulation and industrial development for the arched specification round bamboo materials.It is of great significance for the realization of "rural revitalization","double carbon target"and the development of green building industry.
Preparation Process Optimization for Ultra-thin Bamboo Particleboard via Response Surface Methodology
LI Yu, WU Sheng-zhong, WU Ke-qin, YE Shi-jun, LIN Zhi-wei, RAO Jiu-ping
2022, 41(2): 7-14. doi: 10.12390/jbr2022072
Abstract(351) PDF(109)
Abstract:
Using bamboo particles prepared from bamboo processing residues as raw materials,the production process of 4.5 mm ultra-thin bamboo particleboard was discussed.The effects of different adhesive amounts,hot pressing temperatures,times and pressures on the main physical and mechanical properties of ultra-thin bamboo particleboard were investigated by response surface Box-Behnken design methodology,and the vertical density profile was analyzed.The results indicated that the optimal processing parameters were adhesive amount level of 12.2%,hot pressing temperature of 182℃,hot pressing time of 30 s·mm-1 and hot pressing pressure of 2.7 MPa.Under these conditions,MOR,MOE,IB and TS of the ultra-thin bamboo particleboard were 13.8 MPa,2 183 MPa,0.56 MPa and 7.87%,respectively,which meet China national standard GB/T 4897-2015 and China National Forest Products Industry Association group standard T/CNFPLA 3013-2021.Compared with the predicted values of the response surface,the error values of all indexes were less than 10%.The vertical density profile of ultra-thin bamboo particleboard was affected by the preparation parameters,which influenced the main physical and mechanical properties such as internal bond strength and modulus of rupture.
Effect of Hydroxyethyl Methacrylate/Citric Acid Modification on Mildew Resistance of Bamboo
YE Xiang-yi, LIN Jing, SUN Jie-yu, ZHANG Wei-wei
2022, 41(2): 15-23. doi: 10.12390/jbr2022026
Abstract(296) PDF(40)
Abstract:
Because bamboo contains starch and other nutrients,it is easy to get mildewed which reduces its appearance quality and commercial value and limits the application of bamboo products.In this study,the mixed solution of hydroxyethyl methacrylate (HEMA) and citric acid (CA) was used to impregnate bamboo.The monomers underwent in situ polymerization and crosslinking reactions,so as to enhance the mildew resistance of the modified bamboo.The results showed that the bamboo modification was optimized when the concentration of HEMA solution was 6%,the molar ratio of HEMA to CA was 4:1,and the crosslinking temperature was 130℃,which achieved 100% efficiency of mildew resistance.The concerned bamboo materials were characterized by IR,TGA and SEM.The results indicated that (1)in situ polymerization and crosslinking reactions between HEMA and CA occurred in bamboo;(2) The equilibrium moisture content of the modified bamboo decreased slightly,but the thermal stability was not improved significantly;(3) The morphology of starch granules in bamboo remained largely intact after the modification.In summary,it is speculated that the improvement of mildew resistance of the modified bamboo is due to the fact that the HEMA/CA polymers impregnate bamboo and form protective films on the surfaces of starch granules,which prevent the direct contact with mold mycelia and hence achieving the anti-mildew effect.
Variations in Branching and Leaf Unfolding Efficiencies of Bamboo Clonal Ramets in the Interface Area of Pleioblastus amarus and Cunninghamia lanceolata Mixed Forest
CHENG Jian-xin, HE Yu-you, GUO Zi-wu, LAN Chun-bao, XU Sen, YANG Li-ting, YING Yi-shan, CHEN Shuang-lin, WANG Zhong-hua, Hu Rui-cai
2022, 41(2): 24-33. doi: 10.12390/jbr2022076
Abstract(310) PDF(57)
Abstract:
The efficiencies of plant branching and leaf unfolding are closely related to the environment.Pleioblastus amarus is a widely distributed dual-purpose bamboo species.The characteristics of branching and leaf unfolding and the strategy of resource allocation between branches and leaves under different environmental conditions were revealed,which can provide reference for scientific management of Pleioblastus amarus forest.A continuous and expansive bamboo (P.amarus)-fir (Cunninghamia lanceolata) mixed forest was studied,and four types of sample plots were set up in interfacial zones and central zones of both pure bamboo forest and mixed forest.The functional traits of branches and leaves of 1-2 y/o bamboo were investigated and determined,and the allometric relationships between the biomasses of branches and leaves were analyzed.The results showed that mixing promoted the growth of new bamboo crown,the increase of branch number and the expansion of growth space.The interfacial zones were beneficial to enhancing the growth capability of branches and leaves of new bamboo,with the increases of branch length,branch base diameter,the number of leaves,the leaf area and the biomass of branches and leaves.But the difference of functional traits of bamboo branches and leaves in the two interfacial zones was significantly reduced.In the interfacial zones of both pure bamboo forest and mixed forest,new bamboo had higher leaf-branch biomass ratio,leaf area ratio and leaf sprouting intensity,and the strategies of branching and leaf unfolding in pure bamboo forest and mixed forest were prioritized with "utilization" and "occupation",respectively.2 y/o bamboo significantly improved the resource allocation advantage of assimilation tissues,greatly improved leaf sprouting intensity and leaf unfolding efficiency,and generally adopted a "utilization" -oriented leaf unfolding strategy.There was a very significant allometric growth relationship between leaf biomass and leaf area or specific leaf area of 1-2 y/o bamboo,and there was a nearly isokinetic growth relationship between branch weight and leaf area.2 y/o bamboo increased the relative growth rate of leaf area-leaf mass and investment benefit.Clonal integration and mixed growth did not change the allometric growth relationship of branch-leaf size of 2 y/o bamboo,but had a significant effect on that of 1 y/o bamboo.In conclusion,there was apparently an age-dependent effect in branching and leaf unfolding of P.amarus in heterogeneous environment,and new bamboo was more sensitive.There was a significant resource trade-off relationship with clonal integration in the interface area of the experimental forest,which modified the growth plasticity of branches and leaves,and improved the competitiveness and adaptability of clonal ramets.
Effects of Management Measures on Soil Physicochemical Properties,Carbon Mineralization and Enzyme Activities in Phyllostachys edulis Plantations
LV Heng, ZHANG Jian, YI Kui-xin, HUANG Zhi-yuan, ZHANG Xiao-ping, ZHONG Zhe-ke, YANG Chuan-bao
2022, 41(2): 34-40. doi: 10.12390/jbr2022055
Abstract(294) PDF(48)
Abstract:
Moso bamboo (Phyllostachys edulis) plantation is a unique forest type in China with significant carbon sequestration potential.The soil physicochemical properties,carbon mineralization and enzyme activities in Moso bamboo plantations subjected to different management measures (undisturbed (M0),extensively managed (M1) and intensively managed (M2)) were studied in comparison to those in a secondary broad-leaved evergreen forest (CK).The results showed that after reducing the human interference with bamboo forest,the soil nutrient contents increased.Compared with the control,the contents of soil total organic carbon (TOC),total nitrogen (TN),total phosphorus and soluble organic nitrogen as well as soil moisture content in the undisturbed and extensively managed bamboo plantations significantly increased,while the soil bulk density decreased.The soil β-Glucosidase,polyphenol oxidase and peroxidase activities in the 0~20 cm and 20~40 cm layers in the undisturbed and extensively managed bamboo plantations increased notably,but the activity of acid phosphatase decreased.The content of potential mineralizable organic carbon in each treatment ranged from 154 to 844 mg·kg-1,accounting for 0.82% to 2.44% of TOC.Compared with the control,the undisturbed management significantly increased the potential active carbon pool and cumulative carbon mineralization in the 0~20 cm and 20~40 cm layers,followed by the extensive management.Intensive management resulted in significantly higher soil carbon mineralization ratio than those in other treatments.In general,with the increase of management intensity,the soil physicochemical properties and enzyme activities decreased gradually and the organic carbon mineralization ratio increased steadily.Therefore,reducing human disturbance is conducive to enhancing soil fertility and facilitating the turnover of organic carbon in Moso bamboo plantations.
Health Assessment of Fargesia qinlingensis Forest in Taibaishan National Nature Reserve of the Qinling Mountains,China
HU You-ning, ZHU Hui-nan, HE Qiang-li, KANG Hai-bin, YANG Hang, WANG Ping, DU Xi-chun
2022, 41(2): 41-49. doi: 10.12390/jbr2021013
Abstract(316) PDF(117)
Abstract:
Fargesia qinlingensis in Taibaishan National Nature Reserve of the Qinling Mountains has undergone a growth decline due to the flowering and changing environment,leading to widespread concern about the food resources of giant panda.Forest health evaluation is important for determining forest management technologies,and conducive to the restoration and healthy management of the forest ecosystem.Here,using the health assessment index model,we investigated the environmental factors,stand vitality,forest structure and disturbing intensity to evaluate the growth condition of F.qinlingensis,and performed the mean squared decision analysis to determine the health status of F.qinlingensis forest.The main results were as follows:In the criterion layer,stand vitality (0.472),forest structure (0.203),environmental factors (0.188),and disturbing intensity (0.137) were ranked by criteria weights.In the index layer,soil quality,age structure,biomass,flowering ratio,regeneration status,and species diversity had significant impacts on the health of F.qinlingensis forest.Among the 30 plots surveyed,2 were assessed as "super healthy" (accounting for 6.67% of total),3 plots each were categorized as "quite healthy" and "healthy" (10.00% each),6 were"sub-healthy "(20.00%),and 16 were" not healthy "(53.33%).Therefore,the overall evaluation result was" not healthy".Thorough investigations into fertilization,density effect,removal of bamboo rhizomes and stumps,soil improvement,and reduction of forest coverage were suggested in order to ensure the successful regeneration and rejuvenation of F.qinlingensis forest in Qinling Mountains after flowering.
Effects of Herbivory by Ailuropoda melanoleuca and Grazing Livestock on Population Characteristics of Bashania faberi Clones
ZHOU Shi-qiang, ZHANG Jin-dong, Vanessa HULL, LIU Dian, ZHOU Teng-long, HUANG Jin-yan, ZHANG He-min
2022, 41(2): 50-59. doi: 10.12390/jbr2022059
Abstract(241) PDF(43)
Abstract:
Population characteristics are the most intuitive and measurable biological indicators of plants and the functional responses of plants to external interferences and environmental fluctuations.By analyzing the population characteristics of Bashania faberi clones after feeding by the wild giant pandas (Ailuropoda melanoleuca) and grazing livestock,we can understand the impact intensity of the giant pandas and grazing livestock on the clonal population dynamics of Bashania faberi,and the response strategy of clonal populations of Bashania faberi to herbivory of different animals.Therefore,the clonal population characteristics of Bashania faberi in Wolong Area of the Giant Panda National Park after feeding by giant pandas and grazing livestock were determined by quadrat method,and compared with those in the control plots.The results showed that wild giant pandas and grazing livestock reduced the coverage of bamboo forest to 87.85% and 52.95% of the control,respectively.The impact intensity of grazing livestock was 1.66 times that of wild giant pandas.Feeding by grazing livestock hindered the germination,regeneration,growth and development of one-year-old bamboo.Compared with the control,the density of one-year-old bamboo decreased by 97.07%,the basal diameter decreased by 27.78%,and the plant height decreased by 87.93%.Grazing livestock had no significant impact on the basal diameters of bamboo culms of other ages or populations (P>0.05),but significantly reduced the heights of other bamboo culms (P<0.05).Feeding by wild giant pandas mainly affected the number of one-year-old bamboo,causing a decrease of density by 28.13%,and was conducive to maintaining the numbers of two-year-old and even older bamboo and the populations,as well as the basal diameters and the plant heights of bamboo ramets of all ages.Therefore,the diameter distribution of the bamboo populations in the plots for livestock grazing was similar to that in the control plots,which followed a normal distribution pattern with the majority being 3.1~6.0 mm and accounting for 82.21% of the total number.However,the height distribution was quite different,and the peak shifted to the lower end.The number of bamboo culms less than 60 cm in height accounted for 41.21%.The population structure (basal diameter and plant height) of bamboo in the plots for wild giant panda herbivory had a similar normal distribution like that in control plots.Most bamboo culms were 2.1~6.0 mm in basal diameter,accounting for 79.44% of the total number,and were 61~140 cm in plant height,accounting for 70.01%.Thus,livestock grazing has a much greater impact on the clonal populations of Bashania faberi than wild giant panda herbivory,and excessive feeding will lead to the degradation of Bashania faberi resource.Therefore,restricting the quantity of grazing livestock and their grazing area is an effective measure to protect the wild giant pandas and their habitats.
Characteristics of Natural Bamboo Distribution in Shennongjia National Park
WANG Wei, ZHONG Jin-mei, YANG Man, HUANG Xun, YAO Hui, ZHAO Yu-cheng, ZHOU Jie, WANG Tao, LIU Xu-xia, YANG Jing-yuan, LI Zhao-hua, WANG Ling
2022, 41(2): 60-66. doi: 10.12390/jbr2022069
Abstract(365) PDF(46)
Abstract:
Bamboo plants in Shennongjia National Park were investigated by on-site survey in 42 quadrats in bamboo distribution areas.Through systematic surveys and classifications,three genera and eight species of bamboo were found in the survey areas,among which the Fargesia nitida was a newly discovered species in the genus Fargesia.Statistical analysis showed that there were significant differences in the growth characteristics of bamboo plants at different altitudinal gradients.The number of bamboo plants and bamboo cover in the quadrat were positively correlated with altitude (P<0.05),the average height and average diameter of bamboo were negatively correlated with altitude (P<0.05),and the vertical distribution of different bamboo species varied with the increase of altitude.These results indicate that bamboo plants in high-altitude regions have a tendency of dwarfing,weakening and clustering.The growth environment and growth characteristics of different bamboo species were also different,as shown by the facts that (1) the genus Fargesia mostly existed in the form of pure shrub forests or in the shrub layer of mixed forests,and the plant number of Fargesia murielae per quadrat was the highest with an average of 73 plants·m-2;(2) the genus Phyllostachy was distributed on the sunny slope and semi shady slope,and mostly existed in the form of artificial pure arbor forests or in the arbor layer of artificial mixed forests,under which was mainly herbaceous vegetation;and (3) the genus Indocalamus was located in the shrub layer or low shrub layer of mixed forests,growing luxuriantly in the incomplete shade under the forest,and the bamboo was thin and short.The understanding of bamboo species,growth characteristics and their distribution features in Shennongjia National Park can provide an important scientific basis for the conservation of bamboo biodiversity and utilization of bamboo resources in the region.
Analysis of Bamboo Industry Development in Anji County Based on Grey Theory
HUANG Yong, CHAI Qing-hui, LV Heng, TANG Hui, WU Xue-ling, JIN Xiao-dong, ZHANG Zhou-ting, YU Li-hua, HU Ke-yi, LIU Yong
2022, 41(2): 67-73. doi: 10.12390/jbr2022084
Abstract(309) PDF(36)
Abstract:
Based on the output data of the bamboo industry in Anji County from 2011 to 2021,the grey relational analysis was applied to study the correlation between the three bamboo industries and the overall bamboo industry,and the GM (1,1) forecasting model was used to predict the output values of Anji's bamboo industry in the next 5 years.The results showed that the average annual growth rates of the bamboo primary,secondary and tertiary industries in Anji County from 2011 to 2021 were 0.25%,2.16% and 17.93%,respectively.In 2018,the structure of Anji County's bamboo industry changed from a "two,three,one" pattern to a "three,two,one" pattern,and the correlation degree of the tertiary industry showed an upward trend.In the future,the bamboo industry will be expanded and strengthened through project introduction and incubation in accordance with the strategy of "strengthening the secondary industry,propelling the primary industry and facilitating the tertiary industry" .This paper proposes to implement the development strategy of "Relying on secondary industry to promote primary and tertiary industries",encourage the coordinated development of the three bamboo industries,facilitate the deep concerted integration of bamboo culture and bamboo industry,and accelerate the structural adjustment and optimization of bamboo industry to ensure the healthy and sustainable development of the bamboo industry in Anji County.
Research and Thoughts on Group Certification Models of Bamboo Forest Management in Anji County
ZHANG Jian, LV Heng, ZHOU Yi, LENG Li-song, SHEN Shi-yin, HUANG Xiao-lu, LU Jun, YU Li-peng, BIAN Fang-yuan
2022, 41(2): 74-78. doi: 10.12390/jbr2022079
Abstract(248) PDF(55)
Abstract:
Anji County is known as one of the"bamboo counties"in China.The bamboo resources in Anji are rich,and the bamboo sector has become the pillar industry of the county.Implementing bamboo forest management certification is of great significance for achieving the sustainable development of the bamboo industry.This paper introduces the group certification models of bamboo forest management in Anji County at various stages,mainly including enterprise model,association+farmers model,and association+shareholding cooperative model.Meanwhile,the operation mechanism,strengths,and importance of association+shareholding cooperative model are elaborated and analyzed.On this basis,this paper presents innovative thoughts and methods on implementing the group certification of bamboo forest management in the model of association+shareholding cooperative in southern China.
Development of Talent Training System for Common Prosperity of Bamboo Industry in Zhejiang Province
JI Zong-fu, GUO Ren-cong
2022, 41(2): 79-84. doi: 10.12390/jbr2022073
Abstract(302) PDF(90)
Abstract:
As new urbanization proceeds swiftly,the flow of talents from rural areas to cities has intensified.The sustainable development of rural industries is faced with many problems such as insufficient talents,low quality,poor structure and unequal distribution.Zhejiang province's rural area is one of the main battlefields in the construction of "common prosperity" demonstration zone,and the objective of common prosperity cannot be achieved without capable talents.In order to tackle the issues in curriculum setting,teaching method,result evaluation,tracking service and training system pertaining to the personnel training of bamboo industry in Zhejiang Province,the training target system,teaching standard system,practical teaching system,teaching evaluation system and policy support system should be established by the measures of reforming teaching design,optimizing curriculum provision,highlighting practice guidance,unblocking feedback channels and improving system and mechanism,so as to promote the talent training for common prosperity of bamboo industry.
An Analysis of Formal and Layout Features of " Bamboo Wood Fence ": Using the Painting " Wangchuan Villa " of the Past Dynasties as a Clue to Unfold
XIONG Jin-xuan
2022, 41(2): 85-92. doi: 10.12390/jbr2022062
Abstract(225) PDF(97)
Abstract:
The Chinese character "Fence" is of upper-lower structure,a combination of semantic "bamboo" and phonetic "li".After dismantling,it can be understood as the use of bamboo and wood materials to separate the inside from the outside.The use of bamboo and wood materials to enclose the site space is an important component of traditional Chinese construction scheme.However,after the wave of modern architecture,especially during the urbanization in the past two decades,the traditional bamboo and wood "fence" apparently made less appearance in modern construction.As far as the bamboo wood fence itself is concerned,there are many fabrication techniques and special structures.It is a combination of beauty and craftsmanship.It reflects the exquisite balance of traditional craftsmanship and construction concepts,and conveys the idea of harmonious co-existence of traditional construction culture and the nature.Starting from the definition of bamboo wood "fence",this paper attempts to distinguish the various meanings of "fence".On this basis,with the reference of the formal pattern of "bamboo wood fence" in traditional landscape paintings,and taking the painting "Wangchuan Villa" of past dynasties as a clue,the characteristics of the fence,such as facade form and planar layout,are sorted out and analyzed,with emphasis on exploring the implicit meanings behind the construction projects.Finally,the value of bamboo wood fences in contemporary construction activities,and the ensued brand new construction attitude are thereby stressed.