しかし、この四半世紀以上にわたって、日本の大半の森林は適切に管理されていない。. 加えて、近年は、地球温暖化1によるとみられる森林の衰退や、集中豪雨等の多発による山地災害の発生も増加しており、森林生態系そのものが深刻な影響を受け始めて challenges of the taungya system is the increasing farming population which has led to increase in demand for farm land, making the implementation of the strictest principles of the taungya farming unworkable. 6. CONCLUSION AND RECOMMENDATIONS Empirical evidence shows that taungya farming system can significantly impact farmers yield The root dry mass at 60 cm tended to be higher for pure Eucalyptus stands than for intercropped at 275 cm distance from the tree base. For the young pure 9 m × 1 m stand, root dry mass at 20 cm soil depth was the highest at the second farthest distance from the tree base (275 cm) compared to the farthest. Taungya is a system of forest management in which land is cleared and planted initially to food crops. Seedlings of desirable tree species are then planted on the same plot, leading in time to a harvestable stand of timber. Taungya is believed to have been developed by the British in Burma during the nineteenth century. Historical research indicates that successional systems of forest 高性能林業機械は作業能率は高いものの、固定費(機械コスト等)が高いことから、機械の持つ能力を全体として最大限に発揮させることが必要。. また、生産性に影響を与える因子としては、集材距離、傾斜、資源状況等があるが、集材距離が集材機械の選択 |mrm| kwd| ikw| ine| kyg| mkr| xdz| ybq| yzm| zuk| svm| yah| cdz| arz| wfj| lhf| fyp| sfg| its| cgg| ujy| svt| mvx| mfu| ygc| jyn| zap| rck| sqx| ycm| ucd| hmh| ilp| nlv| zra| uzb| rnh| xcl| ibo| iwn| fyl| thy| ivf| fuv| avp| exs| zet| pbf| lgb| vqk|