This paper investigates the characteristics of succession in Lespedeza bicolor var. japonica Nakai and Amorpha fruticosa L. plant communities that were introduced into the same cut slope on the Nishiseto Expressway at Hakatajima by spraying with a soil/seed cultivative base. I have compared the results of 25 years after the application of soil/seed cultivative base with those of a thick cultivative base that was applied at the same time and place. The results of the study are as follows: 1)Natural invasion and growth of woody plant species began to increase from 17 years after the application of each type of cultivative base. 2)Leguminosae woody plants were more effectively promoted natural invasion of woody plant species with seed disposal by birds and small animals. 3)The soil/seed cultivative bases were more effective in promoting broad-leaved deciduous pioneer tree species and Pinus densiflora Sieb. et Zucc. trees. 4)The thickly sprayed cultivative base was more effective in promoting Ligustrum japonicum Tunb. and Quercus phyllyraeoides A. Gray such as broad-leaved evergreen tree species. However, it is quite likely that we can promote a more natural invasion of woody plant communities in areas sprayed with a thick cultivative base, rather than a soil/seed cultivative base, by 1)not developing mono-stratified woody plant communities, such as Lespedeza bicolor var. japonica and Amorpha fruticosa, and 2)in case of planning that introduce Leguminosae woody plants community, decrease the expectative numbers of germination will be drastically, or 3)developing a low-density multi-strata stratified woody plant community by revegetative works to establish a plant community such as that found 25 years after spraying with the soil/seed cultivative base.

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We investigated about an inhabitation of Coenagrionidae on a Ludwigia peploidea Raven ssp. stipulacea Raven community, which is a vulnerable species locally distributed on Kashio River in east Kanagawa. As a result, it was shown clearly that three species, Ischnura senegalensis Rambur, I. asiatica Brauer and Cercion hieroglyphicum Brauer, dominated on this river, and the abundance peaks of each species differed from spring to autumn. Since Coenagrionidae was hardly recorded in a neighboring river, it was proved that the large number of its habitation in Kashio River was exceptional. Especially, C. hieroglyphicum and I. asiatica indicated high abundance among distribution of L. peploidea ssp. stipulacea. Data for larva investigation indicated that the larva density was high in sites on the slower stream. This observation suggests that L. peploidea ssp. stipulacea community inhabited on waterside plays a key role in formation of microhabitats for larva. Data for mark-recapture investigation indicated that the max distance of immigration was about 700 m, and nearly all of recapture individuals stayed on the identical sandbar. To design an arrangement of L. peploidea ssp. stipulacea community at intervals of some hundred meters, it was inferred that this Kashio River function as an ecological corridor for Coenagrionidae in urban area.

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Though two Phragmites species, Phragmites australis(Cav.)Trin. and Phragmites japonica Steudel, frequently planted as a material of waterfront revegetations and riparian buffer zones resemble very much each other, these species can be classified based on their epigeal stolon, the former does not have the epigeal stolon and the latter has the stolon. However, it is recently suggested that the classification of Phragmites australis and Phragmites japonica based on the epigeal stolon will be not appropriate though there is no academic data which proves this. In this study, therefore, Phragmites communities with epigeal stolon and those without the stolon were classified based on their characteristics of inflorescence and genetic positions in the Satunai River, Hokkaido, northern Japan. In addition, the classification of above-mentioned two species based on their some morphological characteristics except for the epigeal stolon were also tried in this paper. Results were as follows; Though Phragmites communities with epigeal stolon were clearly classi-fied as a Phragmites japonica, Phragmites communities without epigeal stolon were not clearly classified as a Phragmites australis because some Phragmites communities without epigeal stolon were classified as a Phragmites japonica based on their characteristics of inflorescence and genetic positions. However, Phragmites communities without epigeal stolon were also clearly classified as a Phragmites australis or Phragmites japonica by confirming their auricles, short hairs on node and long hairs on base of lamina in the culm. That is, in Phragmites communities without epigeal stolon, the communities without auricles or with short hairs on node in the culm were classified as a Phragmites japonica and the communities with auricles, long hairs on base of lamina or without short hairs on node in the culm were classified as a Phragmites australis.

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We conducted experiments on seed storage, seeding, and nursing in order to develop the storage and cultivation techniques for local seeds and seedlings of Rhododendron reticulatum and R. macrosepalum grown in secondary forests in Kyoto city. We concluded in four findings; i.e., 1)Seeds dried under the sun and sterilized keep their vigor longer when they are stored in refrigerator with silica gel. 2)Under this condition, the high germination rate stays for two years and eight months in R. reticulatum and a year and eight months in R. macrosepalum. 3)Germination rate is the highest when they are seeded in the May after fruiting. 4)The surviving rate and growth of both species are the highest in the case their seeds are sown on the sphagnum and transplanted the next early spring to the vinyl pots. A pot with a diameter of 6 cm is appropriate for R. reticulatum, and 9 cm is appropriate for R. macrosepalum for raising 2 years old seedlings under no fertilizer.

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