Harvesting systems of forest biomass resources in village forests

1999 Fiscal Year Final Research Report Summary

• Project/Area Number: 10460061
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 林学
• Research Institution: The University of Tokyo
• Principal Investigator: SAKAI Hideo The Univ. of Tokyo, Graduate School of Agric. and Life Sciences, Assoc. Prof., 大学院・農学生命科学研究科, 助教授 (70126069)
• Co-Investigator(Kenkyū-buntansha): IWAOKA Masahiro Tokyo Univ. of Agric. and Tech. Assistant Prof., 農学部, 助手 (40213269) ; TANGE. Takeshi The Univ. of Tokyo, Graduate School of Agric. and Life Sciences, Assoc. Prof., 大学院・農学生命科学研究科, 助教授 (20179922) ; KOBAYASHI Hiroshi The Univ. of Tokyo, Graduate School of Agric. and Life Sciences, Prof., 大学院・農学生命科学研究科, 教授 (00111394) ; SAWAGUCHI Isao Iwate Univ., Fac. of Agric. Assoc. Prof., 農学部, 助教授 (80302058) ; SHISHIUCHI Masao Iwate Univ., Fac. of Agric. Prof., 農学部, 教授 (10003782)
• Project Period (FY): 1998 – 1999
• Keywords: village forests / forest biomass / chipper / mini-forwarder / harvesting system / slash / forest land / nutrition

Research Abstract

Village forests have high potential of utilizing forest resources for biomass energy and agricultural use. The harvesting systems of Sorest biomass in village forests were investigated.
1. Harvesting system of a mini-forwarder with a grapple crane improved for harvesting forest biomass such as brandies was investigated. Efficiency of transportation of branches was 13 % of that of logs. Efficiency of transportation of chips was 50 % of that of logs.
2. Operational efficiency of chipping by a large sized chipper was 5-20 times as much as that of small sized ones, and 1/3-2/3 in fuel consumption, so that the cost of the large sized one was 1/5-2/3 of the small sized ones.
3. Harvesting cost of forest biomass was 5.03〜26.8 yen/kWh, and the systems of chipping in the forest was cheaper than those of chipping in the plant. These values were 3-30 times as much as those in European countries. But there was a possibility to reduce the difference by developing high efficient small chippers and transportation systems of compresf5ed biomass. Energy for harvesting was mud1 lower than the obtained energy, so that there was no problem from the point of view of energy consumption.
4. It was desirable to harvest only woody part of branches and to leave leaves in the forest to prevent nutrition from reducing. When harvesting forest biomass, it was desirable to avoid clear cut-ting and to introduce cable logging not to disturb forest soil.