2014 Volume 48 Issue 1 Pages 27-24
Stand structure of a 60-year-old secondary forest and a mature non-clear-cut forest were compared in subtropical lucidophyllous forest in the Yambaru area of Okinawa Island. A first dominant species, Castanopsis sieboldii showed a higher stem density in the 60-year-old secondary forest than that in the mature non-clear-cut forest. However, stem density of C. sieboldii with diameter at breast height ＞25 cm in the 60-year-old secondary forest was less than half of that in the mature non-clear-cut forest. The stem size distribution of C. sieboldii had not recovered at 60years after logging. A secondary dominant species, Schima wallichii, showed lower stem density in the 60-year-old secondary forest than that in the mature non-clear-cut forest. Additionally, the sizes of regenerated Distylium racemosum were still quite small, and Quercus miyagii had rarely become established in the60-year-old secondary forest. The stand structure was significantly different in the 60-year-old secondary forest compared with the mature non-clear-cut forest. The species richness was obviously higher in the mature non-clear-cut forest. Mature non-clear-cut forest remaining in the Yambaru area of Okinawa Island is limited and fragmented. Despite this situation, the ecosystems and their biodiversity are still intact and receives praise worldwide. Land managers need to manage conditions in both mature non-clear-cut and secondary forest appropriately, with the goal of maintaining and restoring the ecosystems and their biodiversity.
