Compared with the undamaged Phyllostachys edulis,the wood mechanical properties of bended bamboo for 4-year-old by frost and snow were studied. It was shown that the wood mechanical properties of bended Phyllostachys ...Compared with the undamaged Phyllostachys edulis,the wood mechanical properties of bended bamboo for 4-year-old by frost and snow were studied. It was shown that the wood mechanical properties of bended Phyllostachys edulis were equivalent to or a little less than those of the undamaged bamboo. The bending strength(MOR) of moderately bended bamboo and the modulus of elasticity in static bending(MOE) of heavily bended bamboo were 125.8 MPa and 10 978.9 MPa respectively in the culm base,and compared with those of undamaged Phyllostachys edulis wood,the differences were significant. However,the other mechanical properties including tensile strength parallel to grain,compressive strength parallel to grain and shearing strength parallel to grain etc. Between bended and undamaged bamboo wood,the difference were not significant. The study results could provide data supports for the proper ways of rational cutting,process and utilization of bended Phyllostachys edulis wood.展开更多
以南亚热带中心分布区的毛竹林为研究对象，比较不同生产力水平（Ⅰ：30000±1000 kg·hm -2 a -1；Ⅱ：34000±1000 kg·hm -2 a -1；Ⅲ：37000±1000 kg·hm -2 a -1；Ⅳ：42000±1000 kg·hm -2 a -...以南亚热带中心分布区的毛竹林为研究对象，比较不同生产力水平（Ⅰ：30000±1000 kg·hm -2 a -1；Ⅱ：34000±1000 kg·hm -2 a -1；Ⅲ：37000±1000 kg·hm -2 a -1；Ⅳ：42000±1000 kg·hm -2 a -1；Ⅴ：47000±1000 kg·hm -2 a -1）毛竹林植被和土壤的碳、氮、磷含量及计量特征，探讨生产力水平对毛竹林及土壤碳、氮、磷分布格局及化学计量特征的影响。结果表明：生产力水平对毛竹林植被碳和磷元素在不同器官间分配比例的影响较小，对氮素分配比例的影响较大；除竹叶碳元素分配比例在不同生产力水平间的差异达到显著水平外（P ＜0.01），各器官间碳、磷含量在不同生产力水平间差异均不显著；除竹秆外，毛竹不同器官氮分配比例在不同生产力水平间的差异均极显著（P＜0.01）；生产力水平对毛竹林植被 C∶N、C∶P、N∶P计量比值的影响较小，在不同生产力水平间的差异均未达到显著水平（P＜0.01），毛竹林主要养分元素的计量比具有内在的稳定性，符合“内稳性假说”；生产力水平对林地土壤碳、氮、磷、水解氮和有效磷含量有显著影响，土壤 C∶N、C∶P、N∶P 和 H-N∶A-P 在不同生产力间的差异均达到了极显著水平（P＜0.01）；当土壤N∶P＜14时，主要受到氮元素的限制，本研究中土壤N∶P为4.50～13.89，反映了研究区毛竹林主要受到氮元素的限制，受磷元素的限制较少，且 N∶P 比值随着生产力的提高呈降低的趋势，有可能成为未来毛竹林退化诊断的生态指示指标；毛竹林植被主要养分计量值与土壤主要养分计量值的相关性分析表明，二者间的相关性未达到显著水平。展开更多
文摘Compared with the undamaged Phyllostachys edulis,the wood mechanical properties of bended bamboo for 4-year-old by frost and snow were studied. It was shown that the wood mechanical properties of bended Phyllostachys edulis were equivalent to or a little less than those of the undamaged bamboo. The bending strength(MOR) of moderately bended bamboo and the modulus of elasticity in static bending(MOE) of heavily bended bamboo were 125.8 MPa and 10 978.9 MPa respectively in the culm base,and compared with those of undamaged Phyllostachys edulis wood,the differences were significant. However,the other mechanical properties including tensile strength parallel to grain,compressive strength parallel to grain and shearing strength parallel to grain etc. Between bended and undamaged bamboo wood,the difference were not significant. The study results could provide data supports for the proper ways of rational cutting,process and utilization of bended Phyllostachys edulis wood.
