In Japan, the demand for woody biomass as a source of energy is increasing with current growing of the market size for this source of energy. When woody biomass is used as a source of energy, it is important to consider that the energy balance between the input to produce wood fuel and the output obtained from wood fuel along with the cost of comminuting woody biomass is important. The purpose of this study is to investigate the effects of dimension and species of wood materials on the energy and cost of wood chip production. We measured the power consumption and calculated the energy consumption per dry mass when test specimens such as Sugi (Chamaecyparis obtusa), Karamatsu (Larix kaempferi), and Kunugi (Quercus acutissima) of various widths and thicknesses were comminuted by a disc chipper. Additionally, the productivity of chipper comminuting, and the cost per dry mass of chip production were calculated. The power consumption was in the range from 6.5 kW to 46.9 kW, and it increased when the dimension and density of the test specimens were increased. However, the energy consumption of dry mass was in the range from 45.3 MJ/t to 96.4 MJ/t and it had a tendency to decrease when the dimensions and densities of the test specimens were increased. The comminuting cost was in the range from 632 yen/t to 7,611 yen/t, and it had a tendency to decrease when the dimensions and densities of the test specimens were increased. Additionally, the cost was strongly affected by productivity and was lower when productivity was high. These facts indicate that reduction of energy consumption and cost during woody biomass comminution can be achieved by using materials whose mass is large and by increasing productivity.

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Long-term durability and aesthetic design are two highly desirable traits for outdoor-use wooden products and facilities. In this study, Sugi heartwood specimens treated with wood preservatives (AAC, ACQ, CUAZ, AZNA, AZN) were further finished with coatings (film forming type, penetrating type) and subjected to artificial weathering using fluorescent ultraviolet lamps and water (EN 927－6). The weather resistivity of the specimens was then evaluated by examining changes in color, gloss, and waterproof properties. Wood preservatives after weathering were also analyzed both in the outer and inner parts of the specimens. Change in color and decreases in water repellency of the coatings with wood preservatives were found to be lower than in untreated specimens, indicating that the performances of the coatings were enhanced in the presence of the wood preservatives. Leachability of the wood preservatives was found to be reduced with coatings, implying that the wood preservatives also benefitted from being used in conjunction with the coatings. The researchers therefore conclude that wood preservatives and coatings have a synergistic effect for long-term preservation and weatherproofing of wooden materials kept outdoors, when used together.

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This study clarifies the process of conducting active learning with two characteristically different groups and the resulting changes in participants’ attitudes. At the Fuji Iyashinomori Woodland Study Center, The University of Tokyo, situated in the Yamanakako Village in Yamanashi Prefecture, 20 students from The University of Tokyo and Joshibi University of Art and Design participated in an active-learning joint exercise as part of this study. The students belonged to varied fields of expertise. To grasp basic information about the students, (1) a profile survey was conducted before the exercise, and (2) students’ environmental attitude, self-efficacy, and psychological stability were investigated before and after the exercise; further, statistical comparisons were conducted. (3) After the exercise, participants’ impressions were recorded through selection methods and their writing of narrative data; the latter was organized separately to have an understanding of the transformation process. The analysis revealed that most participants favored the joint exercise. In terms of changes in attitude after the exercise, all participants from Joshibi University had a significantly lower view of the environment than before. It was found that there was a change in the way of thinking about an ideal environment as a result of getting in touch with actual natural environment through exercises and so on. No significant differences in self-efficacy and stability were found; however, in the case of both universities, students’ tendency to change their attitudes, especially the direction of such change, was confirmed. During the process of change, students’ initial image of students from the other university was transformed through their joint work. Additionally, the characteristics and values of self and those of classmates from the same university were rediscovered through the relativization of ideas and each participant’s special skills.

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Tricholoma matsutake is an ectomycorrhizal agaricomycete that produces the prized mushroom “matsutake” when grown in pine forests. At present, T. matsutake cannot be artificially cultivated for fruiting. Using barley-based substrate cultivation, a T. matsutake mutant, designated G1, which was generated by irradiating T. matsutake NBRC 33136 with g-rays, produced protuberances that were composed of non-aerial hyphal tissues. The protuberances occurred in three consecutive independent experiments but did not grow into fruiting bodies. The issue of whether the protuberances represent the initial stage of fruiting needs to be clarified. However, because of morphological changes in the spawn, the G1 strain may be useful in developing a cultivar of T. matsutake.

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The Takaragawa Experimental Watershed is located in Minakami in Gunma prefecture (36°51' N and 39°01' E). The experimental watershed was established by the Kanto Forest Management Bureau in 1937 for the purpose of examining the effects of artificial development of the Okutone Natural Forest on runoff from a mountainous area. Observations of precipitation and runoff have been conducted since the inception of the experimental watershed. Observation data from 1937 through 1990 have been published in several reports. This report builds upon earlier reports by describing daily precipitation and runoff from 1991 through 2000.

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The purpose of this study is to accumulate of knowledge of nuki-column joint using hardwood with a small cross section in order to expand the demand for hardwood that has excellent mechanical performance as a building construction material. A nuki-column joint is one of the traditional Japanese timber joints. This joint consists of a small beam, called nuki, and a column. The authors conducted moment-resistance tests of nuki-column joints using hardwood as a whole or part of the nuki, and grasped the effect and performance of using hardwood at the joints. In this report, the relationships between the moment-resistance performances of the joints with hardwood as reinforcements and the compression perpendicular to the grain performances of the reinforcements were shown. In addition, these relationships were compared to the ones between the moment-resistance performances of the hardwood-nuki and column joints and the compression perpendicular to the grain performances of the nuki. On the other hand, to quantitatively evaluate the rigidity of the post-surrender, we proposed a simple tri-linear replacement method for the test results. As a result, the relationship between the moment-resistance performance of the joint that had the hardwood 24 mm thickness reinforcement over entire length of nuki and the compression perpendicular to the grain performance of the reinforcement had the same tendency as the relationship between the moment-resistance performance of the joints with whole-hardwood nuki and the compression perpendicular to the grain performance of the nuki. In addition, from the characteristic values calculated by our method, we were able to grasp the difference in the joint behavior after the yield point depending on the length of the reinforcements.

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Jozankei Experimental Watershed (JEW), located in a national forest on the outskirts of Sapporo, Hokkaido, Japan, was established in 1987 for the purpose of forest hydrological research in cold, snowy regions. The study site consists of two adjacent smaller watersheds, called Shigure-Ichinosawa and Shigure-Ninosawa. Long-term surveys of precipitation and stream runoff in both watersheds have been conducted. Daily precipitation and runoff data from 1991 to 2012 have already been published. This report describes daily precipitation and runoff data for the five-year period from 2013 through 2017. There were some events to note during this period. High-intensity precipitation of 76.5 mm per day coincided with peak snowmelt-runoff on April 7, 2013, and a large amount of sediment flowed into the sediment reservoirs. At this time, an overflow occurred at the gauging weir in Shigure-Ninosawa. Therefore, we carried out dredging from February 21 to March 3, 2014. Some long-term precipitation data are missing from the observation period. Stand-wither became noticeable during this period. The causes of damage within the watersheds were considered to include the increase in DBH-H ratio and the increase in the Yezo deer population.

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