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163,070,000 Yen
(1) Population structure and dynamics of trees in hill forest: A study plot was established in the Semangkok Forest Reserve. Trees larger than 5 cm DBH(diameter-at-breast height) were tagged and measured. Saplings of Shorea curtisii,Teijsmanniodendron coriaceum and Diospyros venosa were abundant. Small sized saplings of Lithocarpus wallichianus, D. latisepara, Antidesma cuspidatum, and Vatica odorata were not found. While no large sized saplings of D. latisepara, Eurycoma longifolia, Scaphium macropodum, and Xanthphyllum griffitii could be observed. There were marked differences in soil resistances at different topographical conditions . On the ridge the soil resistance was large while on the lower slope resistance was small. There was no apparent difference in the vertical changes of resistance between the directions of slope.
(2) Structure of insect comuunities: Five plots along the gradient from the forest edge to the core were set in the Pasoh Forest Reserve. In every plot, 18 black collision traps were set at 1.5m high and at about 10m intervals in a line. Collected ambrosia scolytids were sorted and identified. Forty-five morpho-species of the ambrosia scolytids were caught; Xyleborus (32spp.), Arixyleborus (5), Xylosandrus (4), Webbia (2), Cnestus (1) and Eccoptop〜erus (1). There was no marked difference in species richness between plots, though the similarity value changed gradually along the gradient. Species composition and richness of the ambrosia scolytids were essentially unchanged from the edge to the core. X. crassiusculus increased gradually from the core to the peripheral area. Catches of X. crassiusculus decreased exponentially with minimum distance from the forest edge.
Hill Forest, Vegetation, Species Composition, Ambrosia Scolytids , Insect Community