In Japan, selective thinning is a common thinning method, though line thinning receives much attention because of its economic merits. In this study, we examined effects of the two thinning methods on bird communities...In Japan, selective thinning is a common thinning method, though line thinning receives much attention because of its economic merits. In this study, we examined effects of the two thinning methods on bird communities in Todo fir (Abies sachalinensis) plantations in Hok- kaido, Japan. We surveyed bird species in forests under four different management types - unthinned, selectively thinned, line-thinned planta- tion, and naturally regenerated forest (here after referred to as natural forest) stands - using a line-transect method. We also investigated vege- tation structure (canopy tree and understory) of these stands. Bird species richness did not differ between natural forests and plantations, while bird total abundance was greater in plantations than in natural forests. Bird species richness and total abundance were comparable among the three management types for plantations. Abundances of 10 bird species were different among the four management types, and five species were more abundant in line-thinned plantations. However, two species were more abundant in selectively thinned stands than in line-thinned stands, and they frequently appeared in natural forests. There were no distinct differ- ences in vegetation structure among the management types for planta- tions. Our results suggest that line thinning could be beneficial for some bird species in plantations.展开更多
文摘In Japan, selective thinning is a common thinning method, though line thinning receives much attention because of its economic merits. In this study, we examined effects of the two thinning methods on bird communities in Todo fir (Abies sachalinensis) plantations in Hok- kaido, Japan. We surveyed bird species in forests under four different management types - unthinned, selectively thinned, line-thinned planta- tion, and naturally regenerated forest (here after referred to as natural forest) stands - using a line-transect method. We also investigated vege- tation structure (canopy tree and understory) of these stands. Bird species richness did not differ between natural forests and plantations, while bird total abundance was greater in plantations than in natural forests. Bird species richness and total abundance were comparable among the three management types for plantations. Abundances of 10 bird species were different among the four management types, and five species were more abundant in line-thinned plantations. However, two species were more abundant in selectively thinned stands than in line-thinned stands, and they frequently appeared in natural forests. There were no distinct differ- ences in vegetation structure among the management types for planta- tions. Our results suggest that line thinning could be beneficial for some bird species in plantations.