This study examined that the relationship between collembolan community structure and habitat in artificial "green lungs". We investigated collembolan communities at 16 stations (2 bare ground, 5 grassland, 4 coniferous woodland, 5 evergreen woodland) along Osaka Bay from October to November 1995. The collembola we collected consisted of 6 families, 23 genera, 30 species, and 5745 individuals. Four pioneer species were abundant : Hypogastrura communis (FOLSOM) from 14 stations, Onychiurus uenoi YOSII from 13 stations, Homidia sauteri (BORNER) from 10 stations, and Proisotoma subminuta (DENIS) from 9 stations. The number of species and species diversity (H') showed significant positive correlation with the vegetation prosperity and the thickness of the litter layer. The number of Collembola showed no significant correlation with any environmental elements examined (including pH, electric conductivity, and water content). The proportions of pioneer species in each community decreased exponentially with increasing thickness of litter. Thickness of litter was the most important factor in determining the species composition of collembolan communities. The removal of weeds, fallen leaves, and twigs prevents the formation of a thick litter layer and influences collembolan communities.
Fragmented lucidophyllous forests preserved in the precincts of shrines and temples were investigated to clarify the influence of forest area decrease on species diversity and composition in central Miyazaki Prefecture. The number of component species of lucidophyllous forest had a high positive correlation with the logarithm of the area. The log of the number of species also showed a high positive correlation with the log area. The log area was positively correlated with the number of micro-landform units and the altitude range of the forests. These results suggest that species richness of fragmented lucidophyllous forest is supported by the habitat diversity of the forest. The component species were classified into four groups according to the similarity of their distributional patterns to the area decrease. Forest floor ferns and epiphytes tended to be absent in smaller forests. There were significant positive correlations between the indices of species diversity, Fisher's α and Morisita's β, in the stand (225 m2) and the log areas.
Variations in the properties of modules, together with their number and disposition within a crown, play an important role in the productive strategies of trees. For example, the differentiation of current-year shoots, which are the representative modules of tree species, into short and long shoots produces a useful division of labor. Short shoots (i.e., short current-year shoots with negligible internodes are oriented to foliage-maintenance. Long shoots (i.e., long current-year shoots with extended internodes) are oriented to crown-expansion. An efficient assimilation system is constructed by disposing the right type of shoots in the right position within a crown, according to the relative importance of foliage-maintenance and crown-expansion in the position. Also in some species without such apparent shoot dimorphism, short current-year shoots display a larger leaf area per stem length than long current-year shoots. as in species with the apparent differentiation of short and log shoots. Moreover, in species without such variations in the leaf area-stem length balance, short current-year shoots have low-cost stems with small stem mass per stem length instead of displaying a large leaf area per stem length. Consequently, their short current-year shoots have a greater leaf mass per stem mass than long current-year shoots. The diverse modes in shoot differentiation may be related to species' characteristics in terms of foliage-crown dynamics, such as the life spans of stems and leaves.