Owase District in Mie Prefecture, located on the south-east side of Kii Peninsula, is one of the wettest region in Japan. Annual precipitation in Owase city is more than 4,000 mm, and warmth index is 128.7℃・Month. Consequently, laurel forests have been able to develop on lowland and mountain slopes. Firstly, a phytosociological study was made of the laurel forests, which were classified into six community types : A, B, C, D, E and F. Pittosporum tobira community (A) is located on the seashore. Quercus phillyraeoides -Pittosporum tobira community (B) is on windy, steep slope, near the seashore. Quercus phillyraeoides - Dicarnopteris dicotoma community (C) is on sites with conditions similar to those of community (B). Castanopsis cuspidata var. sieboldii - Symplocos glauca community (D) and Castanopsis cuspidata - Photinia glabra community (E) are located from the seashore to lower elevations of mountainsides (<400m). On higher mountainsides (about 400〜700m) Quercus salicina - Cleyera japonica community (F) is found. Secondly, I investigated the relatioship between the six community types and site conditions. Owase District is a very wet region, but there are dry sites on the mountainsides where communities A, B and C are found. On less xeric sites, Communities D and E are distributed. On the basis of these results, the relationship between environmental gradient and community structure (complex sinusia) is discussed.
Floristic composition was investigated in the Malus baccata var. mandshurica bush on the sand dunes along the Sea of Okhotsk, in eastern Hokkaido. A phytosociological association, Lonicero - Maletum baccatae, was newly recognized. Its characteristic species are Malus baccata var. mandshurica, Lonicera chrysantha var. crassipes and Sambucus sieboldiana var. miquelii. In the case of the M. baccata var. mandshurica bush, only Roso〜Maletum mandshuricae (Tatewaki 1961) Ohba, Miyawaki et Tx. 1973, has been reported. It belongs to Rosion rugosae Ohba, Miyawaki et Tx. Lonicero-Maletum baccatae lacks Rosa rugosa and Artemisia japonica, but it has many species common to the Angelico anomalae - Quercetum dentatae (Tatewaki 1961) Ohba, Miyawaki et Tx. 1973, the climax forest on coastal sand dunes. It also has many of the character and differential species of its upper unit. Thus Lonicero-Maletum baccatae belongs to Quercion dentatae Miyawaki et Yasushi Sasaki 1980. Fixation of trees in coastal sand dunes is difficult because of the severe environment as a dense sand dune vegetation cover, the strong sea wind and so on. Seeds of M. baccata var. mandshurica are dispersed by birds and can produce root-suckers, allowing it to grow in coastal sand dunes as a pioneer shrub.
Butterfly assemblages were investigated using route census surveys, at Flowertown in Sanda from April to October, 1994. In order to evaluate the naturalness of vegetation through the species composition of butterflies, we proposed a butterfly index, which indicated the degree of naturalness of the habitat. The values of species diversity, averages of the butterfly index, and values calculated by the Bray-Curtis ordination method were calculated for eight vegetational conditions ; outside fragmented forest ; inside fragmented forest ; outside grassland ; inside grassland ; park ; detached house ; multiple dwelling house ; bare area. The results showed that the species diversity and butterfly index were highest in fragmented forests, and were lowest in the bare area. Ecological distribution of butterflies was classified into four types ; forest-type ; grassland-type ; park-type ; others. Many butterflies belonged to the forest-type classification, since there were many plant communities in the fragmented forests, such as Rhododendro macrosepali-Pinetum densiflorae, Quercetum variavili-serratae, Alnus japonica-Ligustrum obtusifolium Comm. Apanantho-Celtidetum japonicae, Querces acutissima Comm. etc. It seemes that fragmented forests are a very important habitat for butterflies, in spite of the small size of such forests. Butterfly assemblages at Flowertown were compared with other localities, including Mino Park, Hattori-ryokuchi Park, Osaka Castle Park, etc. Mino Park, Mt. Nijosan and Mt. Sanageyama were estimated to be at the secondary vegetational stage, while Osaka Castle Park, Nagai Park and Daisen Park were estimated to be at the urban stage. Although Flowertown was at the secondary vegetational stage in terms of butterfly fauna, it was at the residential-urban stage in terms of butterfly assemblages.