The impacts of thinning on the fruiting of saprophytic fungi in Cryptomeria japonica plantations in central Taiwan

Abstract

Forest thinning is an important method for managing forests, changing forest structure, biological diversity and community. This study examined forest thinning effects on macrofungal diversity and the environmental factors affecting fruiting and community structure. Field surveys were conducted from 2006 to 2010 in 35-year-old Cryptomeria japonica plantations in central Taiwan. Thinning was completed in October 2007 and included control, 25% thinning, and 50% thinning treatments. Each treatment had four replications. Forest thinning and time affected macrofungal species richness observed but not abundance. Thinning influenced macrofungal community compositions; however, the difference between the two thinning intensities was not significant. The macrofungal community showed significant differences between communities of eastern and northern aspect. A redundancy analysis indicated that macrofungal communities in the C. japonica plantations were significantly affected by relative humidity, light, canopy cover, soil water content, soil temperature, soil pH value and soil texture. The fruiting of a dominant coral fungal species, Scytinopogon sp., was affected by thinning and light. The fruiting bodies of this species decreased in the 25% thinning plots and disappeared in 50% thinning plots in the first two years post-thinning, but were recorded in the third year post-thinning. After thinning, macrofungal species richness observed decreased, the community changed, and changes were associated with environmental conditions. Forest thinning decreased observable macrofungal diversity and changed the community structure, and these changes were associated with environmental variation after thinning.