Patterns of litterfall and nutrient return at different altitudes in evergreen hardwood forests of Central Taiwan

This study was designed to evaluate the internal nutrient cycling of litterfall in different elevation subtropical forests of Central Taiwan. The litterfall of evergreen hardwoods at three elevations, specifically Mt. Peitungyen (2,078 m), Hui-Sun experimental forest (HSEF) (1,066 m), and Lienhauchi (782 m) in central Taiwan, was collected monthly using traps and sorted into leaves, twigs, reproductive litter, and miscellaneous material. In addition, the litter on the forest floor was collected trimonthly. All the samples were weighed and measured for C, N, P, K, Ca, and Mg concentrations and fluxes from March 2009 to February 2010. The annual litterfall productions were 6.58, 8.24, and 9.17 Mg ha(-1) year(-1) at Mt. Peitungyen, HSEF, and Lienhauchi, respectively. At more than 60 %, leaves were the main component of the total litterfall. There was smallest decomposition constant (0.487) at Mt. Peitungyen. The nutrient fluxes increased as elevation decreased. The litterfall correlated positively with rainfall at Lienhauchi, with temperature at HSEF, and with temperature and rainfall at Mt. Peitungyen. The annual litterfall decreased with an increase in elevation. The turnover rate was faster at HSEF than at Mt. Peitungyen. Thus, the forest managers should pay more attention to understand and monitor plant community responses to global warming and nutrient loss.