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Evergreen broad-leaved forest is now gradually degraded and fragmented, and there is an increase in the amount of habitat edges as a result of long-term human activity. However, the role of edges in the regeneration of primary forest species is poorly understood. After 20 years of the edge creation, we analyzed primary forest species distribution and abundance, and changes in floristic composition, vegetation structure across forest-field gradients in Ailao Mountain, SW China. Our results revealed that there was a higher abundance and richness of primary species, late secondary species and thorny lianas at the distances 0-50 m than at the distances more than 50 m from the edge into the forest exterior. At the distances >50 m, no individuals of dominant canopy trees Lithocarpus xylocarpus, Castanopsis wattii, and L. jingdongensis were found, whereas the abundance of early pioneer shrub species and herbaceous cover was significantly greater. The richness of primary species showed a decrease with increasing distances from the forest edge to the exterior, particularly of medium-seeded primary species showing a drastic decrease. Moreover, no large-seeded primary species occurred at the distances >60 m. This study indicates that the forest edge as a buffer zone may be in favor of primary species regeneration. A dense shrub and herb layer, and seed dispersal may be the major factors limiting the forest regeneration farther from the forest edge. Therefore, to facilitate forest recovery processes, management should give priority to the protection of buffer zones of this forest edge. [ABSTRACT FROM AUTHOR]

We investigated the seedling survival of five evergreen tree species over 3 years inside and outside deer-exclusion fences in a warm temperate evergreen broad-leaved forest on Yakushima Island, Japan. Seedling survival was examined in relation to topography, herbivory by sika deer, and the soil surface environment (i.e., soil surface wetness, light conditions, slope inclination, and soil disturbance). The study species included Myrsine seguinii Lév., Syzygium buxifolium Hook. et Arn. (Group A: species distributed on the upper slope of the study site), Litsea accuminata (Bl.) Kurata, Schefflera octophylla (Lour.) Harms (Group B: species distributed on the lower slope), and Cleyera japonica Thunb. p.p. emend. Sieb. et Zucc. (Group C: species distributed on both slopes). The soil surface environment on the upper slope was drier, lighter, and more easily disturbed than the lower slope. Generalized linear model analyses indicated that seedling survival in fenced and unfenced quadrats was greater on the upper slope than on the lower slope for Group A and B species but not for Group C species. A micro-spatial scale analysis revealed that seedling survival was correlated with soil wetness, ground light conditions, and soil disturbance but not slope inclination. These results indicate that seedling survival was correlated with topography, sika deer herbivory, and the micro-spatial scale environment. Topography-related differences in seedling survival appear to adequately reflect the observed adult plant distributions for Group A and C species but not for Group B species. [ABSTRACT FROM AUTHOR]

For the purpose of phylogeographic study of lucidophyllous (evergreen broad-leaved) forests in Japan, we surveyed intraspecific chloroplast DNA (cpDNA) variation in 41 component species of such forests. Intraspecific cpDNA variations were detected in 14 species. In 15 species and one species group, 16 non-coding cpDNA regions were examined to find intraspecific sequence variation. The extent of variation in these regions was compared. The largest amount of intraspecific variation was detected in the rps16 region. A relatively large amount of intraspecific variation was detected in the petD-rpoA, rpl16, and trnL-F regions. It is suggested that these regions of cpDNA would be useful for detecting intraspecific variation in plant species, and could provide valuable information for various research purposes. [ABSTRACT FROM AUTHOR]