Harvesting systems of forest biomass resources in village forests

乡村森林利用森林资源作为生物质能源和农业用途的潜力很大。调查了村落森林中索勒斯特生物量的收获系统.研究了一种用于白兰地等森林生物质采伐的小型抓斗起重机集材机的采伐系统。树枝输送效率为原木的13%.木片输送效率为原木的50%.大型削片机削片作业效率是小型削片机的5-20倍，耗油量是小型削片机的1/3-2/3，成本是小型削片机的1/5-2/3.森林生物质的收获成本为5.03日元/kWh，森林中的削片系统比工厂中的削片系统便宜。这些数值是欧洲国家的3-30倍。但是，通过开发高效的小型削片机和压缩生物质的运输系统，有可能减少这种差异。用于采集的能量比获得的能量低mud 1，因此从能量消耗的角度来看没有问题。4.最好只收获树枝的木质部分，并将树叶留在森林中，以防止营养减少。在采伐森林生物量时，最好避免皆伐，采用电缆采伐，以免破坏森林土壤。

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.