“Kikigaki Kousien” is a project undertaken in 2002. This attempt was supposed to enhance high school students to meet farmers and foresters through on-site fieldworks. This essay examines three outcomes of “Kikigaki Kousien” and its social impact on forest environmental education through questionnaire and interviews to farmers, foresters, high school students, and sponsors. Firstly, foresters and students had the opportunity of intergenerational communication through this project. Farmers and foresters shared their experience and knowledge with the participants who are not familiar with these industries, and also became more motivated in boosting their work leand improving behavior as well. Secondly, the project has seen the short-term and long-term effects among the high school students. As the short-term effect, all the students enhanced communication with the others across Japan. It was a good chance for them to meet foresters and deepen their knowledge on agriculture and forestry. On the other handregarding the long-term effect, half of the participants changed their behavior and way of thinking about natural environment, while the other half mentioned that the project supported them to clarify their future career and backed up the decision-making. Thirdly, FamilyMart Co. Ltd. is willing to sponsor the project in recognition of the participation of high school students. Hence it is necessary for sponsors to avoid limiting the scale to Cooperate Social Responsibility and consider the project from many angles.

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To elucidate the source area of leaf litter in streams, we investigated the travel distance of leaf litter from willow (Salix spp.) trees at two flat riparian forests in Hokkaido (in Akagawa and Yufutsu). We marked the willow leaves by spray-painting them to an aboveground height of 13.5 m using an aerial work platform, and we surveyed their dispersal with litter traps. Leaves of the upper crown were found to disperse within 15-25 m from the base of the trunks, whereas leaves of the lower crown were found to disperse within only 5-15 m because the heights from which they fell were relatively low. Directional differences in dispersal area were related to wind direction during the leaf fall season, and there were positive correlations between maximum dispersal distances and wind intensities. Leaf litter redistribution on the forest floor was surveyed using artificial leaves from late fall until late spring. The average travel distances of the leaves were very short (0.04-2.15 m), and the travel directions relate to the directions of strong winds (≥5 m/s or ≥6 m/s) near the floors. Leaf litter travel distance at flat riparian forests in snowy region is considered to depend more on leaf dispersal during leaf fall than on redistribution on the floor.

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We investigated the species diversity and composition of carabid beetle assemblages in secondary deciduous broad-leaved forests in which litter is or is not removed annually to make compost in Motegi, Tochigi Prefecture, northern Kanto. The census for carabid beetles was conducted once a month from May to November in 2012, using 15 pitfall traps per plot, in three litter removal plots and three non-litter removal plots. Environmental factors (e.g., litter thickness, dominance of dwarf bamboo, and mean openness) and the density of earthworms were also measured in each plot. The environment of the forest floor was obviously different between the forests with or without litter removal. However, no clear differences in the diversity and community composition of carabid beetles were found between the forest floor treatments.

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The Great Zelkova of Hirose Shrine (Zelkova serrata Makino) is considered to be about 1,000 years old and is reportedly difficult to propagate by axillary bud culture. Therefore, a new method of propagation was studied for this tree. Adventitious twigs, which grew from the trunk, were sampled in the end of October. The twigs were dipped in water, and nodal explants of the sprouts were cultured in Z medium for shoot elongation. Elongated shoots longer than 3 cm were cultured in R medium for rooting, and the remaining explants were re-cultured in the original test tubes. The shoots were cultured up to five times with a rooting rate of 63%. The shoots were maintained in darkness until the base of the shoot enlarged and showed a rooting rate of 84%. After acclimation and growth in a nursery, the plantlet survival rate was 76%. This method is effective for the preservation of natural monuments and precious trees that do not require mass propagation.

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The forest on the Pacific coast of Tohoku was severely damaged by the tsunami triggered by the 2011 Tohoku Earthquake. The characteristics of the changes to the groundwater level must be clarified for the regeneration of a healthy coastal forest. Groundwater levels were observed in the coastal forest in Miyagino-ku, Sendai, Miyagi Prefecture in December, 2011 after the earthquake. Precipitation and groundwater level were low during the winter. The groundwater level was high during heavy precipitation in the rainy season and during typhoons from July to October. The monthly maximum groundwater level increased with increasing monthly precipitation. We estimated the monthly maximum groundwater level for the last ten years based on observations. The monthly maximum groundwater level was estimated to range from -0.73 to 0.30 m (mean: -0.46 m) in the area where pines were uprooted by the tsunami. This result suggests that a high groundwater level has influenced the development of the root systems. The pines on the embankment of the Teizanbori Canal escaped damage by the tsunami. The groundwater level at the embankment was estimated to range from -3.05 to -1.99 m (mean: -2.77 m). This result suggests that the embankment was the site environment that was able to develop healthy root systems.

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Satoyama books were analyzed in order to clarify public interests and concerns on Satoyama secondary forest use and management. First, the NDL Search Database of National Diet Library of Japan was used in order to collect every commercial book which has a word ‘Satoyama’ in its title. As a result two hundred and sixty nine Satoyama books were found. The first Satoyama book appeared in 1985 and Satoyama books have been constantly published after 1990's. Especially ten to twenty Satoyama books were constantly published every year in the twenty first century. The target readers were adults in the early years but were spread to school pupils in the twenty first century. Satoyama books were found in every first hierarchical level of Nippon Decimal Classification (NDC) Standards of Japanese books. This means that public interests and concerns were spread into all genres of academic topics. Also, Satoyama books were referred to thirty two of forty seven prefectures. This means that public interests and concerns of Satoyama were geographically spread throughout in Japan. Lastly the keyword analyses of Satoyama books using KJ Method suggested that public interests and concerns were divided into seven types and further sub-divided into fourteen sub-types. It can be pointed out that these results clarified in this paper should be used in government Satoyama secondary forest management policies or Satoyama recreational use planning and so forth.

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Recent advances in laser technology enable us to capture detailed forest structures quickly and accurately. In the past, airborne laser has been used intensively to measure stand level attributes, such as average tree height, individual tree crowns, canopy cover, canopy stratification, and tree height growth. Using terrestrial lasers we can obtain more accurate stem volume and stem density by identifying the stem structure. Moreover, with the terrestrial laser, we can measure the upper part of stem and crown without human error, which was impossible using conventional ground-based manual measurement. LiDAR has contributed to various fields of forest ecosystem studies in estimating forest light and hydrological environments, predicting stand dynamics, and quantifying parameters for forest conservation. We expect that terrestrial lasers will be used more widely in forest ecological research to quantify physiological function of trees, large-scale, long-term monitoring of forest dynamics, as well as environmental assessment. This fine scale measurement technology has the potential to capture various structural attributes of forest ecosystems, which would allow us to understand and measure ecological processes quantitatively in forest ecosystems.

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