多雪環境下における樹木の力学的特性Ⅱ

抄録

Abstract: An investigation of vegetation and mechanical tests were conducted to clarify dynamic characteristics of trees in heavy snow areas in Japan. The vegetation association was Hamamelido‒Fagetum crenatae. There is a plasticity of tree strength from snow through an examination of bending. Tree characteristics were divided broadly into patterns through dynamic examination. Aesculus turbinata, Tilia japonica, Magnolia obovata, and Acer rufinerve showed lower strength. A. turbinata, T. japonica, and M. obovata had lower dry specific gravity values. These species were thought to have soft and light wood materials. Ulmus laciniata and A. rufinerve showed lower dry specific gravities. It was suggested that both species could be faster-growing species as well as the three species listed above. A. turbinata showed lower water content among these five species. Tilia japonica and U. laciniata are regarded as species demanding higher water content. Acer japonicum, A. sieboldianum, A. argutum, Fagus crenata, Euonymus planipes, and E. alatus var. apterus f. ciliatodentatus showed higher dynamic strength than the five species mentioned above. A. argutum, Euonymus planipes, and E. alatus var. apterus f. ciliatodentatus indicated much higher fracture strength values in spite of having the scrub shape. Fagus crenata, Acer japonicum, and A. sieboldianum did not show strain energy per volume to branch size dependency. This suggested that species have individual ecological and morphological characters in their habitat.