In order to clarify the effects of human disturbance and forest fragmentation on the lucidophyllous forest, we compared species composition and richness among the following three types of lucidophyllous forest in Miyazaki Prefecture in southeastern Kyushu, Japan: (1) primeval lucidophyllous forest; (2) natural lucidophyllous forest, i.e., small patches of shrine forest in which no periodic clear cutting has occurred but where there has been occasional, low-impact human disturbance as well as a high degree of fragmentation by human development; and (3) secondary lucidophyllous forest, i.e., coppices that were used as a source of firewood and charcoal. We set a total of sixty-two 100m^2 plots (11 primeval plots, 19 natural plots, and 32 secondary plots) at the study sites. In each plot, all vascular plant species were identified. The species composition clearly differed among the three forest types; that of the natural forests was intermediate between those of the primeval and secondary forests. Species composition was strongly influenced by both human disturbance and forest fragmentation. Compared to the primeval forests, species that prefer shade and mesic soil and epiphyte species were absent or rare in the natural forests. The number of species per plot for all species and that for the component species of lucidophyllous forests tended to be lowest in the primeval forests, followed in order by the natural and secondary forests. The number of species that occurred disproportionately in the primeval and natural forests when compared to the secondary forests was highly and positively correlated with forest patch area for these two types of forest, indicating that forest fragmentation causes the decrease in species richness.

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Relationships between forest floor vegetation and micro-landform were investigated in Pterocarya rhoifolia forests in Shikoku, Japan. Five types of micro-landforms in the forests were distinguished in this study: channel; terrace of debris flow; foot slope; lower sideslope; talus. Six types of forest floor vegetation of Pterocarya rhoifolia forests were distinguished. Peracarpa carnosa var. circaeoides community was established only on talus composed of rocky materials. On the other micro-landforms, some communities were established. Viola shikokiana community was established on the lower sideslope that consisted of organic deposits. Leucosceptrum stellipilum var. tosaense community was established on higher terrace of debris flow and lower sideslope not affected by fluvial processes. Meehania urticifolia community was established on foot slope having poor organic materials. Leucosceptrum japonicum community was established on foot slope and the lower terrace of debris flow mainly composed of sand and gravel. Eutrema japonica community was established on channels in the riverhead. Forest floor vegetation of Pterocarya rhoifolia forest was multiunit of these herbs influenced by not only micro-landform but also the soil condition.

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Information on understory vegetation is important for evaluating a terrestrial ecosystem and animal behavior. In recent years, various statistical methods have been developed for predicting vegetation or animal habitat from a geographical database. However, there have been few studies that examine understory vegetation with predictive mapping; hence, we attempt to construct a predictive model for the understory cover degree of dwarf bamboo and a predictive map from the GIS database in the home range of the golden eagles on Mt. Akita-Komagatake. Canopy dominant species roughly correspond to the degree of understory coverage of dwarf bamboo; however, certain dominant species show statistically insignificant data and are randomly distributed in comparison to the data of the degree of dwarf bamboo cover. The result of the classification tree shows that the canopy dominant species, canopy height, and topographic illumination value at the summer solstice were the main factors affecting understory dwarf bamboo; the discriminant accuracy of the model was approximately 76.3%. By using this model, the map of the cover degree of dwarf bamboo understory was easily constructed from the GIS database. In summary, the dwarf bamboo understory map can be constructed by the GIS database and it indirectly indicates the understory light environment.

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We investigated vegetation, ground water level and fluctuation, topography, peat accumulation and vegetation changes of Shinoro Mire, an isolated peatland remnant of Ishikari Mire, once the largest mire in Japan. Many pools and drainage ditches have been dug in the mire, which is surrounded by asphalt roads, landfilled areas and drainage ditches. We classified vegetation into five herbaceous communities (Moliniopsis japonica-Sphagnum comm.; Phragmites australis comm.; Moliniopsis japonica comm.; Sasa comm.; and Miscanthus sinensis・Sasa comm.) and one forest community (Betula platyphylla var. japonica・Alnus japonica comm.). Vegetation changes were rapidly progressing as a result of drainage. It was observed by aerial photography Moliniopsis japonica-Sphagnum community had formed where the surface peat have been removed. Topographic survey indicates that there are a few places with lateral flow, a result of banking or landfilling. The water level was high in fall, winter and early spring snowmelt season. In the summer season it was lower and its fluctuation was much greater. Consequently the peat from the ground surface to 50cm depth was in a state of decomposition. These results show that the mire environment is threatened and mire is in danger of being lost.

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Seed germination and burial experiments over more than 12 months were carried out in the field to reveal the potential for persistent seed bank formation in 14 plant species (11 native species and 3 alien species) which are dominant and/or characteristic species of coastal sand dunes in the warm temperate zone in Japan. Results of the seed germination experiment, in which seeds were sown at depths of 0cm and 5cm, suggested that Lathyrus japonicus, Glehnia littoralis, Calystegia soldanella, Vitex rotundifolia, Wedelia prostrata, Carex kobomugi, Carex pumila, Fimbristylis sericea, Oenothera laciniata, Diodia teres and Lolium rigidum could form persistent seed banks close to the sand surface, but that Ixeris repens, Ischaemum anthephoroides and Zoysia macrostachya could not. Results of the seed burial experiment, in which seeds were buried at a depth of 100cm over more than 12 months, suggested that all species could form persistent seed banks at that depth. Seed dormancy or quiescence at a burial depth of 100cm would be due to the soil temperature. The burial depth of 20-30cm would be enough to inhibit seed germination. At a zone where the sand accretion rate is high, most of the dispersed seeds would be buried deeply and would form persistent seed banks. In contrast, at a zone where the sand accretion rate is low, the possibility of seed bank formation would vary depending on the dormancy and germination characteristics of the species.

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