Local distributional patterns of wetland shrub Myrica gale var. tomentosa were investigated in relation to microtopography in the Ozegahara Mire, a montane mire in central Japan. Increases of the area of distribution and biomass of the Myrica were reported in the mire from the 1950s to 1980. The whole area of the mire was divided into grid cells of 25×25m, and the presence or absence of the Myrica, its canopy height and microtopographic features were recorded in each cell. These values were compared in three main areas of the Ozegahara Mire, i.e. the Kamitashiro, the Nakatashiro and the Shimotashiro areas, which were isolated from each other by streams. Frequency of occurrence of the Myrica differed significantly among the three areas of the mire, i.e. 71.1% in the Nakatashiro, 25.8% in the Kamitashiro, and 2.1% in the Shimotashiro. The frequency of occurrence decreased with increasing elevation except for the lowest elevation class. Large distributional gaps were observed in the upper reaches of streams and highly raised peat plateaus. Canopy height was related to microtopography. Canopy height of the Myrica was high in low elevation habitats such as riversides and woodland edges, while it was low in high elevation areas distant from streams or woodlands, where bog vegetation predominated. The Myrica was newly observed at sites adjacent to boardwalks. Canopy height of the Myrica was significantly higher in cells containing boardwalks than in cells without boardwalks. The Myrica's pattern of occurrence and size adjacent to boardwalks suggests that boardwalk construction will promote Myrica's establishment and growth.

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This study focused on the emergence and establishment of seedlings of five perennial plant species in order to investigate the seed propagation of coastal dune plants on the Enshu-nada coast, Shizuoka Prefecture, central Japan. Seedlings of Carex kobomugi had been successfully established on the tidal drifts in the back of the foredune. The tidal drifts had the effect of stimulating the growth of seedlings due to increased N-NO_3^- in the soil. Therefore, it was considered that Carex kobomugi had spread into the bare area through the tidal drifts. The establishment of seedlings differed among species at the foredune. Five coastal dune plants were divided into two groups: those with a low survival rate of seedlings (Carex kobomugi, Ixeris repens and Calystegia soldanella), and those with a high survival rate (Ischaemum anthephoroides and Fimbristylis sericea). In the former group, adult plants were established in each micro site of the foredune, irrespective of the densities of the emerged seedling and their survival. In the latter group, a large number of seedlings were observed at the micro sites, where adult plants were established. Moreover, the former group can spread through rhizome formation, but the latter group can not. It was concluded that Carex kobomugi, Ixeris repens and Calystegia soldanella mainly depended on vegetative propagation, while Ischaemum anthephoroides and Fimbristylis sericea mainly relied on seed propagation to maintain their population at the foredune. The role of seed propagation differed among coastal dune plants at the foredune, and the establishment of seedlings differed between the tidal drifts and the foredune.

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We investigated the characteristics and environmental conditions of alpine plant communities distributed on the lower position (1820m a.s.l.) of a block slope along a subalpine belt on Mt. Kurohime, Nagano Prefecture, central Honshu, Japan. This site is 1200m^2 in area and commonly known as "Tengu-no-Roji". Although alpine plants, such as Vaccinium vitis-idaea, Empetrum nigrum var. japonicum, and Loiseleuria procumbens, were distributed at the site, the seedlings of trees from the subalpine belt (e.g., Betula ermanii and Abies mariesii) were also present. There existed very little soil matrix on or among blocks, and the deposition of organic matter on the block was thin; therefore, the growth of trees was remarkably limited. The litterfall of Pinus pumila and Tsuga diversifolia growing along the edge of the site (Tengu-no-Roji) increased the thickness of organic matter deposition on the block slope, allowing trees to grow within this alpine plant community. T. diversifolia and Thuja standishii, which throve on the slope, further augmented the layer of organic matter deposition, and the vegetation of the block slope shifted to a mixed forest of coniferous and broad-leaved tree species, primarily consisting of A. mariesii and Betula spp. The alpine plant community of the study area showed a relic distribution remaining after the migration of subalpine tree species during a postglacial warming period. Our results suggest that the unique plant distribution of the study area resulted from the accumulation of huge blocks that prevented soil developments. Continuous low temperatures at the cool-spots site may allow the alpine plants to thrive there.

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In order to clarify the distribution of the bryophyte species in relation to micro-landforms, a vegetation survey was carried out in the conifer plantations of Cryptomeria japonica and Chamaecyparis obtusa in Mt. Tsukuba, Ibaraki Prefecture. The distribution of bryophyte species was compared with those of flowering plant species and pteridophyte species. We discussed the ecological significance of micro-landforms on the distribution and species diversity of bryophyte species in Cryptomeria japonica and Chamaecyparis obtusa plantations. The number of species which showed significant distribution bias for a specific micro-landform was highest in bryophytes, followed by pteridophytes and flowering plants. In particular, a large number of bryophyte species were found only on the bottomland. Average numbers of bryophytes species, pteridophytes and flowering plants in each of the microlandforms increased in the order of crest flat, crest slope, upper sideslope, lower sideslope, footslope and bottomland. The distribution trend of bryophytes along micro-landforms was similar to that of the pteridophytes rather than flowering plants. It was suggested that the distribution of plants in Cryptomeria japonica and Chamaecyparis obtusa plantations was influenced by the changing environ-mental conditions as the distance from the channel increased. We conclude that the bottomland provides a key habitat for the Cryptomeria japonica and Chamaecyparis obtusa plantations with species diversity, indicating the importance of bryophytes which were found only on the bottomland.

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The lucidophyllous forests on Mt. Ichibusayama (Kumamoto Pref.), Kawanaka (Miyazaki Pref.), Mt. Omoridake (Miyazaki Pref.), Mt. Kurinodake (Kagoshima Pref.) and Shiratani (Yakushima Island, Kagoshima Pref.), were studied in order to clarify the species composition of the vascular epiphytes of the lucidophyllous forest and the relationship between host tree size at breast height (DBH) and species richness of the vascular epiphytes (epiphytic richness) on each host tree. In these forests, a total of 586 host trees (45 species), including 84 Distylium racemosum, 66 Persea thunbergii, 60 Quercus acuta, and 376 others were chosen as sample trees. The vascular epiphytes on the host trees comprised 37 species, including Lemmaphyllum microphyllum, Bulbophyllum drymoglossum, and Davallia mariesii. The common characteristic of the vascular epiphytes flora of the lucidophyllous forest in Japan was the dominance of ferns and orchids. The species composition of the vascular epiphytes was compared among five localities. The vascular epiphytes were assorted into 8 species groups according to the summarized table of the frequency (%) of occurrence and mean coverage (%) of each species. The species composition of the vascular epiphytes in five localities was characterized by the combination of the species groups, respectively, and each locality had a different species combination. The species composition of Mt. Kurinodake was similar to that of Mt. Ichibusayama. The species composition of Kawanaka and Shiratani was different from each other. The ordination obtained by Detrended correspondence analysis (DCA) revealed that three groups (Kawanaka, Omoridake-Mt. Ichibusayama-Mt. Kurinodake and Shiratani) of host trees (stands) were clearly different from each other. The difference of species composition among the five localities was due to the climatic conditions of the localities. The species richness of the vascular epiphytes on each host tree in five localities or in seven host tree species had a high positive correlation with host tree DBH (cm), respectively. This relationship in five localities or in seven host tree species was expressed by the equation: y=ax+b (where y is the number of vascular epiphytes, x is the DBH (cm) of the host tree, and a and b are the constants). The constants of the five localities or seven host tree species are different, respectively, due to the precipitation and humidity of the localities or the properties of the host tree bark.

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