Dynamics of Litter Decomposition in Natural Forests of Castanopsis Carlesii in Jian'ou and Wuyi Mountain

The primary purpose of this study was to reveal the amount, composition and seasonal dynamic characteristics of litters in the natural forest of Castanopsis carlesii in the mid-subtropical zone. By using the method of directly collecting litters, the monthly litters of Castanopsis carlesii natural forests in Jian'ou (the average age of the main forest layer was 200 years) and Wuyi Mountain (the average age of the main forest layer was 50 years) have been collected for one year since 2013, and the quality of litters and the content of each component were measured. The results showed that the annual total amount of litters of Castanopsis carlesii natural forests in Jian'ou and Wuyi Mountain were 9 530.49 kg·hm^-2 and 5 590.18 kg·hm^-2, respectively, and the annual amount of litters in Jian'ou was significantly higher than that in Wuyi Mountain (P<0.05). The annual total amount of litters of Castanopsis carlesii natural forests in Jian'ou and Wuyi Mountain showed a single peak model, and the peak value appeared in March and April, respectively. The seasonal change rule of the annual amount of litters was spring>summer>autumn>winter. Among the four components of branches, leaves, fruits and sundries, the litter leaves accounted for the largest proportion, accounting for 50.5%-67.2% of the annual amount of litters, followed by branches (13.1%-20.8%) and sundries (14.5%-17.8%), and the fruits (1.9%-14.2%) were the lowest. The seasonal changes of each component of litters were all high in spring and summer, but low in autumn and winter.