[Effects of plant foliar litter diversity on the growth of Chinese fir seedling and the absorption of (15NH4)2SO4].

Effects of plant foliar litter species composition on the growth of the potted Chinese fir seedling and the absorption of (15NH4)2SO4 was studied. The result showed that there were significant growth responses to foliar litter treatments. A very noticeable trend was that as the tree species of foliar litter placed on pots increases, the growth of Chinese fir seedlings increases steadily. Seedling growth in four-species mixed foliar litter were the largest and that in Cunninghamia lanceolata + Michelia macclurei + Kalooanax septemlobus foliar litter mixture were the second. The others were in order of seedlings in C. lanceolata + M. macclurei + Castanopsis carlesii foliar litter mixture > C. lanceolata + K. septemlobus foliar litter mixture > C. lanceolata + C. carlesii > control (no foliar litter) > C. lanceolata + M. macclurei foliar litter mixture > Chinese fir foliar litter treatment. The recovery of (15NH4)2SO4 by Chinese fir seedlings in no foliar litter treatment was maximum, and seedlings grown in four foliar litter mixture was the second, then it was in order of C. lanceolata + C. carlesii + K. septemlobus = C. lanceolata + C. carlesii + M. macclurei > C. lanceolata + K. septemlobus > C. lanceolata + C. carlesii > C. lanceolata + M. macclurei > C. lanceolata foliar litter treatment. In addition, the residue of (15NH4)2SO4 was greater in soil with foliar litter treatment than in no foliar litter soil. Both of the residual amount of (15NH4)2SO4 in soil and the total recovery of (15NH4)2SO4 increased with the increasing tree species of applied foliar litter.