1993 Volume 43 Issue 3 Pages 169-179
The distribution of Castanopsis and Persea forests and its causal factors were studied on Hachijo-jima in the Izu Islands. Castanopsis forest dominated Mt. Mihara, a volcano of the Pleistocene period situated in the south-east of the island, and a mixed forest of Castanopsis and Persea was restricted to valleys. Mt. Hachijo-Fuji, a volcano of Recent origin situated in the north-west of the island, was dominated by Persea forest, whereas Castanopsis forest was rare. The soils on Mt. Mihara were well developed, whereas those on Mt. Hachijo-Fuji were not. On Mt. Hachijo-Fuji, Persea forest was distributed on lava flows and scoria, whereas Castanopsis forest was distributed on lava flows as well as erosional valleys but not on the original surface of scoria. These facts suggest that the macro-scale distribution pattern of Castanopsis and Persea forests was formed by succession from Persea forest to Castanopsis forest, while the micro-scale distribution patterns were formed by the difference between the succession pattern on lava flows and scoria.
