To clarify land-use change from a time when rural resources were fully utilized to the present, inhabitants were questioned in parallel with an examination of documentary records in a rural village near the city of Shiso, in Hyogo Prefecture. Formerly, rural resources were sustainably utilized through well-regulated controls at the community level. The pattern of land use was broadly classified into housing sites, cultivated areas, forest areas, and grasslands. The areas of broadleaf forest and grasslands occupied 50% and 40% of available land in the early 1930s; these have now decreased drastically to 9% and 4%, respectively. The decrease is mostly due to a change to coniferous forest following extensive afforestation in the 1960s. Prior to the 1960s, the area comprised coppice woodland for firewood, grasslands for feeding cattle, and other grasslands for thatching materials. The development of new energy sources, such as electricity and fossil fuel, and of new technology, such as mechanical cultivators, have caused a marked change in the landscape through a decrease in rural resource demand.

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A condition for depopulation prevention in mountainous areas is whether there is work that sustains people's lives, however, it is difficult to sustain lives only with agriculture or forestry. In the past, there were attempts to attract factories and promote resort development, nonetheless, all of them failed. The Ministry of Internal Affairs and Communications noted the necessity of local autonomous industries "based on their own innovations." In the Kashimo area, of Gifu, which is the subject area of this study, they have developed local autonomous industries since the early period after WWII. One industry is the woodworking industry. Woodworking in Kashimo operates on a small scale, however, there are quite a few varieties. By analyzing (1) differences by types of businesses (products) and (2) differences by business owners from the point of view of sales and the number of engaged workers, this study will clarify their autonomous entrepreneurial viability. Brush handle makers demonstrated a peak in sales and the number of engaged workers in 1980s, but both of them drastically decreased due to imported products, nonetheless, a portion of them survived through diversification and a change in business. Compared to sales during the economical bubble period, they are now down to half, but the joinery business has remained steady by connecting with the local direct sales housing sector. One of the main reasons for the survival is considered to be the differentiation from imported goods. In addition, the existence of innovation has determined the success of the individual business owners.

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Rhododendron reticulatum is commonly used in landscaping because of its beautiful flowers, and it is also commonly found in abandoned secondary forests in western Japan. In this study, we investigated flowering in the crown and shoot levels of R. reticulatum and assessed the dynamics involved in flowering. We found that flowering rate increased with an increase in the basal diameter of stem. With regard to floral bud formation on the shoot, foliate buds formed on shoots with a large diameter, and floral buds formed on shoots with a small diameter. Floral shoots formed in the previous year did not allow floral bud formation in current year. Dry mass of floral shoots was similar to that of foliate shoots, but the morphological characteristics of lateral shoots, such as length, branching ratio, and cross-sectional growth, were different between floral shoots and foliate shoots. Thus, flowering in the crown is regulated by the basal diameter of the stem, whereas floral bud formation is regulated by the production of floral shoots in the previous year. We found that crowns that grow to a particular size develop flowers and extensive flowering in the crown occurs when all shoots show extensive formation of floral buds.

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Seasonal patterns of stem diameter growth of individuals of woody species were analyzed at Mt. Mikasa, Nara, Japan. The process of the growth was fitted to a simple logistic curve, which was used to estimate growth parameters for each species. Growth patterns were categorized based on life forms of the woody species. Possibly due to the high photosynthetic rates and the short life span of their leaves, deciduous broad-leaved species grew quickly over a short period. Conversely, evergreen conifers grew slowly over a long period, and evergreen broad-leaved species showed growth characteristics that were intermediate between deciduous broad-leaved and evergreen coniferous species. Evergreen coniferous and evergreen broad-leaved species would compensate for their slow photosynthetic rates by having extended growth periods which enable them to keep sufficient growth. Among evergreen coniferous and evergreen broad-leaved species, those species with more northerly distribution started growing earlier in spring; however, no tendency was observed in deciduous broad-leaved species. Since evergreen species retain their leaves throughout a year, they will be able to photosynthesize and grow immediately after environmental conditions become favorable. Among evergreen conifers, species that started growing earlier had longer growth periods. Conversely, in deciduous broad-leaved species, the length of the growth period was influenced by the date of growth cessation. For deciduous species that require considerable resources to produce new spring foliage, maintaining growth until late in the growing season may be necessary to maximize growth. Differences in seasonal growth patterns among woody species may promote coexistence among species in a forest.

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The characteristics of CH_4 emission in relation to the amount and diameter of organic matter, especially roots litter in the forest are poorly understood. Therefore, we examined the potential of methane emission from root litter using a closed chamber method. We used the Yamashiro Experimental Forest (YEF) located in Kizugawa city in the southern part of Kyoto prefecture. An investigation plot was set in the riparian zone of YEF. This plot was the model area for woody root litter under the water table. A high rate of methane emission was observed on the soil chamber that contained a large amount of root litter. Especially, the emission rate after 20 days was relatively high and it was not related with diameter. These results suggest that woody root litter is an important potential source of methane in the forest. Further studies of root litter as a source of methane may be needed.

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