The fertile riparian alluvial lowlands were converted into rice paddies since ancient times in Japan leading to the permanent loss of riparian forest. In modern days river restoration and flood control works changed the original states of the riparian forest. Therefore, closely observing and studying the natural riparian forest we experimented and finally could come up with a method to reproduce a model riparian forests structure that is close to the natural riparian forest which could help restore the damaged riparian vegetation in Hokkaido. The method to reproduce the model is called "eco- mixed seeding and planting method " which has already produced fruitful results through experiments in Hokkaido.

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The objective of this study was to investigate the various factors that affect the understory population in a Neglected Moso bamboo（Phyllostachys heterocycla (Carr.) Mitford) forest This investigation was conducted in the Yatsuyama Hill at Aoi-ku, Shizuoka City. Soil temperature, air temperature and photosynthetic photon flux density (PPFD) were measured both inside and outside the bamboo forest. The results showed that the soil temperature and air temperature were low and the summer PPFD was even lower in summer season inside the forest compared with the outside. The nitrate nitrogen concentration inside the bamboo forest soil was lower than that of the soil outside of bamboo forest. Investigations on the number of seed bank inside and outside the bamboo forest showed that 316 seeds were found outside of bamboo forest compared with 222 seeds inside of bamboo forest. The number of germinated seedlings in bamboo forest increased temporarily in the middle of May, but it decreased gradually after that. There was also a remarkable increase in the number of dead bamboo leaves inside the forest. This factor was considered to have influenced the seed germination. When seeding of the Rhus succedanea seeds was carried out on the dead leaves of bamboo, the rate of germination reduced remarkably. From the results of these investigations, it can be concluded that the understory population became poor inside the bamboo forest. The presence of numerous dead bamboo leaves inside the forest also affected the seed germination of all the species. Moreover, plants did not grow well inside the bamboo forest, due to poor light intensity

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The forest of the seasonal floodplain of Lake Tonle Sap, Cambodia, the largest fresh water lake in South East Asia, is dominated by Barringtonia acutangula Korth (Lytheraceae). However, the widespread invasion of the introduced shrub Mimosa pigra L. (Legminosae) in areas affected by severe human impact, including burning off, is having serious implications for local flora. In this study, the processes of revegetation by M. pigra from establishment until dominance, were surveyed in an open area (ca. 0.7ha) from which the aerial parts of plants had been burnt off four times (before and after flooding) over a 21 month period. Vegetation was investigated by phytosociological methods in 50 randomly set 1 m² quadrats and RPPFD calculated from a hemispherical photo taken 50cm above the center of each quadrat. The revegetation process was as follows: (1) one week after burning, Merremia hederacea Hallier f. (Cuculbitaceae), a pioneer species with herb climber, widely established, (2) 1.9 months after burning, M. hederacea widespread (41.7% coverage of quadrats), scattered M. pigra and B. acutangula in low densities, (3) 14.5 months after burning (following initial flooding)，M. pigra regenerated primarily from sprouts growing more quickly than other species, dominant with high coverage (64.2%) and height (2.1m), (4) 21.9 months after burning (following second flooding), M. pigra dominance increased, with greater coverage (90.2%) and height (2.9m), other species covered completely. In the early stages of revegetation following burning on the Lake Tonle Sap floodplain, the recovery ability of M. pigra was clearly greater than that of B. acutangula, a dominant species in the region.

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This study aims to investigate the effectiveness of capturing fish using hand nets in order to develop an understanding of the relationship between fish and river environment. This study presents information that target people (e.g. citizens, students) can learn from the fish that were captured using hand nets. The investigation was carried out in a wand-pool that was connected to the trunk of a river. The result confirmed that some fish (e.g., Carassius spp.) spawned and grew, while others (e.g. Zacco platypus ) took shelter in the wand-pool during the period between spring and summer; the habitat-use behavior of fish is useful helping the target group understand the fish-river environment relationship. However, it was difficult to obtain habitat information related to the typical behavior of Rheophilic fish (e.g., Tribolodon hakonensis ). Therefore, perhaps a supplementary method using casting nets is required to capture such types of fish.

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The aim of this research is to understand the criteria for what is considered “livable” among students as well as their impressions and perspectives towards rural areas as a place to live and work. When making assessments and judgments on the “livability” of a given place，one’s past life experiences are used as the criteria. This research indicated that the criteria which vary among individuals are influenced by one’s hometown.

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Training environmental leaders, who can contribute in creating a sustainable society in Asia, is considered an urgent task for higher education institutions in Japan. As an initial step towards its role, Yokohama National University developed and implemented a training program in Thailand in cooperation with the Prince of Songkla University. This study examined the educational effects of the program, participants’ evaluation of the program, and safety management.

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