A quantitative comparison of pteridophytes diversity in small scales was conducted among regions of Malaysian tropical, Taiwan and Ryukyu subtropical and Japanese temperate forests. Accumulating number of pteridophytes on 25 cubes of 5 m × 5 m × 5 m was about 55, 30, 20 and 10 spp. in the warm temperate, subtropical, cool temperate and tropical forests floor, respectively. Among different habitats near Kuala Lumpur, the highest gamma-diversity (26 spp. / 40 cubes of 5 m × 5 m × 5 m) was found at Semangkok natural tropical forest and the lowest was (12spp. / 40 cubes) on oil palm trunks. The highest beta-diversity was 7 on 10 yrs forest gap at Pasoh, the lowest was 2 on oil palm trunks. Alpha-diversity represented by mean number of species per cube was the highest as 6.5 at natural forest floor at Semangkok and the lowest as 2.4 at forest gap at Pasoh.
Space more than 20 cubes of 10 m × 10 m × 10 m and 5 cubes of 20 m × 20 m × 20 m showed the higher accumulating number of pteridophytes species at natural forest than those of other artificially disturbed habitats. Pronounced tropical natural forest consists of highest bio-diversity (especially tall trees) wide range of forest is necessary for the maintenance of the high phytodiversity of pteridophytes in Malay archipelago, since pteridophytes flora is poor in small scales.

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The spatial distribution, survival and growth of Elateriaspermum tapas Blume (Euphorbiaceae) were studied from the data of a 1-ha permanent plot at Gunung Berni, West Kalimantan. In the plot, number of species and individuals of Euphorbiaceae were 35 and 254, respectively and the most abundant and dominant was E. tapas. Forty four percent of seeds produced in a mast fruiting season could be escaped from predators and germinated into seedlings. The number of the established seedlings was drastically dropped in the next year of the mast fruiting and slightly increased in the second year.The species has classical inverse J-shaped frequency size distribution, suggesting its continuous regeneration. The species was contagiously distributed in the plot. Mortality of shorter seedlings was higher than that of taller seedlings, and the mortality of seedlings in the gap was slightly higher than that of in closed forest. The mortality rate of seedlings was not related to the density of cohort seedlings and variables representing stand structure. The relationships among measured tree dimensions drew a simple linear; suggesting the growth pattern of tree dimensions in each individual plant was closely dependent one to another. The RGR-height tended to decrease in hyperbolic manner by increasing the height of seedlings and saplings, and the RGR-height in the gap were consistently higher than that in the closed forest. The RGR of height on seedlings and saplings or the RGR of diameter on trees in the sub-plots was not significantly related to the variables representing stand structure and relative light intensity ambient the individuals.

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The spatial distribution and correlation between ginger species were analyzed in two 1ha study plots (Plots 2 and 3) in the Mount Halimun National Park, West Java, Indonesia. Plot 2 had wetter soil and gentler slope than Plot 3. The number of observed shoots and species diversity of Zingiberaceae were higher in Plot 2 than Plot 3. All of five representative ginger species were distributed contagiously in the plots, and the clump sizes were larger in Plot 3 than Plot 2. Alpinia scabra BI., one of the most abundant ginger species, indicated negative spatial correlation with other subdominant species in both plots. These results seemed to be related to water content of soils and inclination of topography. Various environments require different adaptive above- and below-ground architecture for the plants. Each ginger species exhibited their own unique architecture, and were contagiously distributed on restricted, optimal sites for their survival and growth. It might decease competitive interactions and contribute to the maintenance of species-rich Zingiberaceae community.

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Biological growth on the surface of basalt rock monoliths by a wide variety of microorganisms including bacteria, (fungi and algae), lichens, mosses and liverworts were studied. Microscopic identification, quantification and an ecological classification of the micro-organisms on two different sites were made to aid the study of their implication in crack and pitting observed on monoliths surface. The result of this study reveal significant differences and some similarities in growth between the chosen sites and the existence of some of the micro-organisms family species in Japan. A complex biotic chemical weathering on the surface of the monoliths was distinguished. Over 450 of the cylindrical monoliths are affected. The communities in this region regard the monolith to represent their ancestors. The monoliths are monuments protected as important cultural property of national interest.

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We examined soil quality characteristics of two long-term observation plots, 1.0 and 0.9 ha, in tropical rain forest in the Mt. Gadut area near Padang, West Sumatra, Indonesia, with regards to tree species diversity. We measured detailed soil chemical and physical properties in 30 × 30 m sized subplots from the two plots. The two 1-ha plots are extending about 1.2 km from a ridge of andesite ⁄ limestone origin where one plot is located to another ridge of shale origins where the other plot is located. Our major aim was to determine whether clear relationships between soil edaphic characteristics and tree species diversity would be recognized. More species and a higher population were found in the plot with low fertility. Furthermore, the variation in soil properties was wider in that plot. To characterize the correlation of spatial distribution between tree species diversity and various soil quality factors, we calculated an omega index of Iwao. The results of comparing species number and various soil properties in 30 × 30 m sized subplots were that the concentrations of elements such as extractable Ca, Mg, AI, Si, Mo, Sr, Sand Zn, as well as the total carbon and total nitrogen showed negative omega values, that is, resulted in a negative correlation, in relation to the species numbers. On the other hand, the variations of the majority of soil quality characteristics, except for extractable Ca, Sand Zn, showed a higher positive correlation to the species number. These results suggest that soil heterogeneity could contribute to creating a diverse edaphic niche for supporting tree species diversity in a few ha size of a few km scale in the Mt. Gadut area. However, this heterogeneous edaphic nature is at least partly the result of the extremely diverse nutritional characteristics of the tree species found in this area.

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A new pollination syndrome, squirrel pollination, was found in a tropical rainforest in Lambir Hills National Park, Sarawak, Malaysia. Madhuca sp. (Sapotaceae) has flowers of which stamens and petals fuse together to form fleshy and berry-like corollas. The corollas are as sweet as 15 %in sugar concentration as sucrose equivalent. The berry-like corolla is easily detachable from pistil/ovary which is bitter to taste. Three species of squirrel, Callosciurus prevostii, Sundasciurus hippurus inquinantus, S. lowii and a species of flying squirrels, Petaurista petaurista were observed to forage on flowers at high frequency. Squirrels and flying squirrels were observed to take away the corolla from the twig, to hold by hands to eat it. Pollen was observed to be attached to the fingers and the fur around the mouth. Although pollen transfer from the tree to the other tree was not confirmed, the behavior of squirrels and flyingsquirrels could act as pollinators.

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We studied the resource allocation process of a large viviparous seed species, Bruguiera gymnorrhiza, during seedling establishment, to clarify the ecological significance of large storage resources in the propagule in mangrove forest. The propagule contained high content of starch in the hypocotyl (51.6 % of the total 7.25 g mean dry weight of the hypocotyl) and a little glucose and fructose. The starch content was evenly distributed in the hypocotyl, except the top and bottom ends, where the content was lower. The hypocotyl starch was gradually consumed after they start rooting. By the time the first pair of leaves appeared (the 30 days after planting) 1/3 of total starch disappeared. The dry weight of the roots and leaves increased consistently and the weight of the both organs seemed almost same. The hypocotyl starch was completely exhausted by the 120 days after planting. The dry weight of new organs did not stop increasing throughout the experiment. Although only 1/3 of hypocotyl starch was necessary to initiate first pair of leaves, consumption of the storage reserves were continuously consumed for the development of leaves and roots. This suggests that the large amount of storage resources in the propagule of B. gymnorrhiza is necessary for the growth during rather long after they start rooting, and help a seedling to recover from herbivory and physical damage, which are frequent in mangrove environment.

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