We have continued observations of environmental changes in abandoned paddy fields in a site near Gifu University, where live three species of freshwater fish, Lefua echigonia (hotoke-dojo), Zacco sieboldii (numamutsu) and Misgurnus anguillicaudatus (Dojo). As well as ordinary rivers, the stream flows there interact with topography, vegetation, soil properties and organic matters, such as litter falls, dead grasses and so on. In this condition, the inhabitation of fishes is comparatively stable.

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Human-beings have access to nature through technology and through the times we can see that human-nature relationship has been changing end evolving. However, it is clear that today’s technology, although very advanced, has been causing problems as well as benefits, principally when the subject concerns the natural environment. These results are difficult to observe and to measure because they occur usually in different time spans and distant locations. We see this phenomenon as a lack of care from the human side. In this article, we apply Maruyama’s Mindscape typology as a tool for human self-observation and as a subsidy to find out new directions for human-nature relationship.

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Saccostrea echinata （Quoy et Gaimard,1835) named Nise-magaki in Japanese is a tropical oyster species that ranges throughout the tropical zones from Japan through Australia. Owing to the topical nature, its geographical distribution in Japan was recorded only in the Yaeyama Islands below 24°20’ N in 1981. In this report, we first verified an occurrence of Nise-magaki S. echinata in the temperate zone of Japan. Since S. echinata is morphologically similar to Magaki Crassostrea gigas (Thunberg, 1793), a reliable molecular taxonomical method was developed by PCR-RFLP analysis that generated distinctive fingerprints between S. echinata and C. gigas. A total of 58 oyster specimens were collected in December 2005 and September 2006 at the intertidal zone in Nichinan, Miyazaki, Japan (31°35’ N). PCR amplification of an apparent 530 bp fragment encoding the mitochondrial 16S ribosomal RNA gene was successfully carried out on all specimens collected, and direct digestion of the PCR products using SacI restriction enzyme enabled to diagnose 5 specimens of S. echinata. This result suggests a possible diffusion of tropical Nise-magaki approximately 1,000 Km to the northward along the Kuroshio Current.

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The present paper proposes a concept and procedure for nature restoration. Engineers should treat nature restoration in a sequence of the procedure as medical doctors examine a patient as follows: a. awareness of the issues, b. listing up the causes and narrow down the lists, c. analyses of the causes, d. consolidation of the constraints, e. choice of the countermeasures, and f. prediction and evaluation of the effect of the measures. Based upon the procedure, a restoration example of a river running through an alluvial fan located in a large city. Additionally, tasks for the future nature restoration projects are discussed regarding: a. promotion of a project taking nature restoration into account as the common view of the people concerned, b. flexible budget operating, and c. importance of the human resource development.

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Rivers have structures consisting of various spaces formed with many elements and factors. Aquatic animals inhabiting there use the spaces appropriately according to certain purposes, such as spawning, feeding, refuge to complete their life cycles. Clarification and evaluation of these structures, called as "environmental structures", are one of important subjects on the restoration of river environment. We have carried out field studies on the environmental structure in a mountain stream. The evaluation was tried to examine whether representative aquatic animals there, nektonic and benthic fishes and a larval insect, can complete their life cycles or not. Their inhabitation conditions were compared with flow and riverbed properties obtained from field survey and numerical simulations. The results show that this stream has an excellent environmental structure.

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Multi-standard forest road network design was presented which is combination design of forest road, monorail for forestry and low standard road for operation. The design was useful for forest logging operation considering terrain condition. Cell-system forestry operation was presented and showed its usefulness and efficiency, depending its standardized transportation and operation. Even on steep hill side, like in Japan, simplification and standardization on forestry operation by the multi-standard forest road and the cell-system is useful to manage logging operation keeping profit business account. Multi-standard forest road design is also useful to conserve forest environments.

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Recently, the environment of urban area has been deteriorated due to growing global wanning, heat island phenomenon, air pollution and enlargement of heat pollution. Maintenance an creation of green zone in the urban areas are important issues because they alleviate the deterioration. Therefore, physiological characteristics of photosynthesis and transpiration in the trees were studied in order to help understanding above role of the trees, and the tree species which are useful for environmental restoration were selected. It was suggested that the deciduous broad-leaved trees such as Quercus serrata Thenb. and Quercus acutissima Carr. had marked effect of restoration. As the second step, small scale forests where above mentioned trees had been planted near urban areas in 1974 and 1989 were surveyed. As a result, amelioration of the effects of air pollution and of heat island phenomenon, and enhancement of absorption and accumulation of carbon dioxide due to forest could be estimated． These results provide an example of effective forest-making for environmental restoration.

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[in Japanese]

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We have conducted research on organisms and the environment in order to implement construction that is friendly to living creatures in the target water channel. Six species of fish and twenty-two species of benthos were found. It was assumed that the following four points could be the important factors as environmental conditions: (1) stable quality water flows throughout the year (2) there is continuity which enables upstream/downstream migration (3) the bottom sediment consists of silt (4) the shape of the river allows the stream to change. Based on these results, construction was implemented in such way that the habitat environment of the currently existing living creatures could be recreated.

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[in Japanese]

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An activity for the revival of Genji-firefly was conducted by the public hall of Ishiuchi area in Hiroshima City and many residents of that area participated this activity. They studied about living conditions of Genji-firefly through breeding of larvae, and cleaned the river where they had been enjoyed the mysterious light of this insects. Then the fire-fly was successfully revived. This activity was to be cooperated by children of elementary schools and residents of this area and to be contributable to cultivate their interest in ecosystems and environmental problems.

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[in Japanese]

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Yatsuyama Hill in Shizuoka City is located about 2 km northeast of JR Shizuoka Station. It has a gross land area of about 91 ha and sits at an altitude of 108 m above sea level. Yatsuyama has been used to cultivate green tea or mandarin orange till around 1985. Later, when Yatsuyama was developed into home lots, it lost its function as a farmland. In recent years, due to the reduction in the numberb of farmers, Yatsuyama went to ruin and the bamboo population increased. In order to tackle this situation, a private volunteer organization "Yatsuyama Saisei Kyougikai" was started in April 2006. The volunteers are working to re-forest and restore the steep range of Yatsuyama into a rich, green and safe natural woodland where citizens can relax. This paper reports on the present condition of this re-forestation project.

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[in Japanese]

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[in Japanese]

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