福岡県御手洗水流域ヒノキ不成績人工林における下層植生の違いがササラダニの種多様性に与える影響

We investigate effect of understory vegitation on species diversity of oribatid mites in warm-temperate Japanese cypress plantation. Four understory types were selected, uncovered with understory (C), covered mainly with evergreen broad leaved understory (E), with deciduous broad leaved understory (D) and with sasa bamboo understory (S). In all the sites, the dominance of canopy Japanese cypress is more than 90% in total basal area. We observed 2654 individuals and 121 taxa of adult oribatid mites. Species richness and Shannon-Wiener diversity index (H') of oribatid mites is higher in E, D, and S than in C. The difference in species composition was higher between C and the others, E, D and S than among E, D and S. Though the dominance of understory was quite low in forest plantation, the effect of understory on species richness of oribatid mites should be important in mono-dominant cypress plantation.