PS 25-82
Forest dynamics over 24 yr in a tropical lowland rainforest, Taiwan: Influences of monsoons, typhoons and climate change
The 3-ha Lanjenchi forest dynamic plot was located in a tropical lowland rainforest which was greatly influenced by winds of the winter monsoon and typhoons. All free-standing trees with diameter at breast height (DBH)≥ 1 cm in this plot were identified, measured, and mapped in 1990, 1997, 2005, and 2013.
Results/Conclusions
In the last 24 years, changes of species composition were few. Stem density decreased monotonically, from 12,147 ha-1 to 10,067 ha-1. In spite of the decrease in stem density, the basal area increased from 40.84 m2 ha-1 to 44.60 m2 ha-1. Annual recruitment rates (1.74 %– 2.05 %) were constantly lower than annual mortality rates (2.10 %– 2.28 %). The re-sprouting rate (7 %) of damaged individuals in this plot was much higher than that (1%) in an adjacent site located in a valley (less affected by winds), indicating that re-sprouting might be a strategy to cope with the strong winds of monsoons and typhoons. Most of the 36 species (42.4 %) which population size decreased monotonically were those only found on the windward slopes of the winter monsoon. This might be associated with the decreasing monsoonal wind speed due to climate change.