2022 Volume 47 Issue 4 Pages 486-494
I investigated the species diversity of woody plants on the forest floor in a coppice forest where undercutting management has resumed by environmental taxes in Tochigi Prefecture. I set up a 10-year continuous management zone, a 5-year-ago management zone, and a 20-year abandoned zone and measured the population density and tree height of each species in eight 10 m2 quadrats. As a result of surveying 24 quadrats, I recorded 3,947 individuals from 47 woody plants growing in the area. In the 10-year continuous management zone and the 5-year-ago management zone, Rhododendron kaempferi and Acer crataegifolium dominated. These species were concentrated in the lower height classes. It was thought that these species would have a small size and survive by sprouting in large numbers with continued undercutting. The species richness and population density increased significantly with management intensity, especially in the 10-year continuous management zone, where the average was as high as 360 individuals/10m2. With the resumption of undercutting, the diversity index increased significantly compared to the 20-year abandoned zone. But, there was no increase in the index value in the 10-year continuous management zone where undercutting was continued compared to the 5-year-ago management zone where undercutting was done once. The number of species (r＝－0.906), population density (r＝－0.766), and diversity index (r＝－0.690 to －0.704) were all negatively correlated with the community height of Pleioblastus chino. The lowest correlation coefficient of the diversity index was because some species, such as R. kaempferi and A. crataegifolium, grew prominently in the 10-year continuous management zone.
