| Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) is the most important plantation tree species in South China However, yield decline and soil degradation have widely occurred in Chinese fir stands with the increasing of plantation areas and generations. This problem has caused considerable attentions. In order to improve monotony species, search fast growing and high yield species which also can maintain fertility, to some extent, replacing Chinese fir has already been one of important measures which can carry out forest sustainable management in South China forest region. Fokienia hodginsii Henry et Thomas is native tree species in China , with beautiful appearance , straight stem ,fast growth and fine texture, has high economic value, ecological value and aesthetic value. Compared with more than 1000 years history of Chinese fir silviculture, F. hodginsii was almost in wild. There were rare studies on F. hodginsii Henry et Thomas in our country, thus there were no systemic reports on F. hodginsii litter quantity, composition, nutrient, energy, decomposition etc. In order to compare its biological and ecological characteristics with Chinese fir in full scale, from January 1999 on, the research had been carried out in two pure plantations of Chinese fir and F. hodginsii, Xiaohu work area of Xinkou Experimental Forestry Farm of Fujian Agricultural and Forestry University, Sanming, Fujian province. Both forests land were covered with native Castanopsis kawakamii forest before plantation in 1967, respectively. From aspects of amount, components, seasonal dynamics of litter, the nutrient content and return, decomposition of litter and energy release had been investigated on forest fertilizing .The results indicated:1. During the three years, the annual litterfall of F. hodginsii was 7318.33 kg hm"2-yr"', which was 31.84% higher than neighborhood Chinese fir stand (5550.95 kg-hm'2-yr"'). Leaf litter was the rmost important component of litterfall, and it accounted for 65.29% and 57.84% of total litterfall in F. hodginsii and Chinese fir , respectively. The monthly variety of F. hodginsii total litter showed two apexes, peaked in April to May and November to December annually. The monthly change pattern of total litter of Chinese fir forest showed three apexes, which occurred in April to May and November to December, respectively. The seasonal dynamics of F. hodginsii total litterfall mass were winter>spring>summer>autumn; and that of Cunninghamia lanceolata forest was spring> sumrner>autumn>winter.2. N, Ca and Mg were high in leaf litter, and P, K were richest in flower litter and cones litter, while all nutrients content were lowest in branch litter,. There was remarkable Among all nutrients, only K and Mg had significant difference, among different months. Both N and P content in the leaf litter of F hodginsii stand were negative correlated with the its' amount. In both stands, the caloric value were highest in leaf and flower litter; The dynamic of caloric value in total leaf and leaf litter were both highest in spring.3. The content of N, P in the leaf litter of F. hodginsii was significant higher than those in leaflitter of Chinese fir, but the P and Mg content in twig litter remarkably lower than those in Chinese fir stand. The caloric value in leaf litter of F. hodginsii was higher than that in Chinese fir, but the value in twig litter was a little lower than that in Chinese fir twig litter. The leaf litter of F. hodginsii had more easy-decomposed matter, such as water-soluble matter, semi-cellulose and crude protein, than the leaf litter of Chinese fir, but less recalcitrant constituents which difficultly to be decomposed, such as lignin, cellulose.4. The annual total nutrient mass that returned to soil through litter in F. hodginsii plantation (139.604 kg.hm2) was 1.16 times than that of Chinese fir plantation (120.018.394 kg.hm-2). The sequences of various nutritive element return were same in the two stands, and the same to nutrient content, that was: Ca>N>K>Mg>P. There...
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