Effects of artificial gap creation on the stand structure of an abandoned evergreen coppice

We examined the effects of artificial gap creation on the diversification of simplified stand structures in an abandoned coppice. A study plot was placed in a 49-year-old evergreen coppice, and two canopy gaps of ca. 100 m 2 were artificially created by logging in December 1992. In 2015–2016 (22–23 years after gap creation), stand structure was resurveyed and compared between a gap-treated plot (PT) and control plot (PC). PT was separated into gap (G), gap edge (GE), and forest interior (FI) parts, and their structures were compared. G and GE, where recruitment of new stems/individuals was expected, had no increase in small stems in 2015 and 2016, showing a mono-modal height distribution pattern in PT similar to PC. Species number also showed no difference between PT and PC, demonstrating a large proportion of species common to PT and PC. No species specific to G and GE was found. In PT, resprouted stems recovered their individual heights during the study period, resulting in a re-simplified local structure and canopy closure. From these results, we concluded that artificial gap creation in the studied stand was insufficient to diversify the stand structure at a mid-term (20 years) scale, and that repeated cutting and/or control of the resprouted stem density is required for diversification of abandoned coppices.