STUDIES ON BIOMASS AND PRODUCTION OF THELOWER SUBTROPICAL EVERGREEN BROAD-LEAVEDFOREST IN HEISHIDING NATURAL RESERVEVII. LITTERFALL, LITTER STANDING CROPAND LITTER DECOMPOSITION RATE
Abstract:Litterfall and its monthly variation, litter standing crop, and the litter decomposition rate in the lower subtropical evergreen broad- leaved forest of Heishiding Natural Reserve, Province Guangdong, were studied from Aug. 1989 to Aug. 1991. the forest is at 400 m above sea level , which was dominated by Ixonanthes chinensis, Artocarpus styracifolins, Ormosia glaberrima, Crypto-carya cancinna, Calamus rhabdocladus, Cibotium, barametz, etc. As measured, amount of small litter-fall including leaves, branches less than one centimeter in diameter, flowers and fruits, and trash was 5. 230 t · ha-1 per year (mean for 2 yrs. ) among which leaves, branches, and flowers and fruits were 3. 550(68. 22%), 0. 837(15. 81%), and 0. 582(10. 97%) respectively. It was obvious that the litterfall varied monthly. Greater leaf litterfall occured in the wet season, with a peak in April, while flower and fruit litterfall was more in Autumn and Winter. Big branch (diameter over 1 cm) litterfall was 0. 34 t · ha-1per year (mean for 2 yrs. ), with significant yearly variation. Litter standing crop amounted to 5. 545 t · ha-1, among which leaves, branches, and flowers and fruits were 3.275 (59.06%), 1. 618(29. 18%), and 0. 131(2. 36%) respectively. Leaf litteffall and standing crop of leaf litter were about 1/4 and 1 /5 of the leaf biomass respectively. It took about 5 months for the litter to lose half of its weight in wet season. The lit ter decreased to 19 % of the original weight in 18 months.