6种阔叶树种幼苗生物量分配特征及模型构建OA北大核心CSTPCD

Two-year-old seedlings of six broad-leaved species,Phoebe bournei,Castanopsis fordil,Mytilaria laosensis,Quercus glauca,Quercus sessilifolia,and Schima superba,were obtained from the Baisha State-owned Forest Farm in Shanghang County,Fujian province,China. The biomass of the roots,stems,leaves,and whole plants of each species was determined by using the whole-plant harvesting method. The allocation characteristics of biomass and the isometric growth relationship between aboveground and underground biomass were compared. Regression estimation models for the biomass of each organ and the whole plant were established using regression analysis. The results showed that:(1) the whole seedling biomass of different tree species was significantly different,and the order was Q. glauca>M. laosensis>C. fordil>Q. sessilifolia>S. superba>P. bournei;(2) there were significant differences in the distribution of biomass among the organs of different tree species,with Q. glauca,M. laosensis,and P. bournei having the largest proportions of root biomass (39. 9％),stem biomass (45. 0％),and leaf biomass (49. 2％),respectively;(3) the ratio of belowground biomass to aboveground biomass of the seedlings of different tree species was less than 1,indicating that more seedling biomass was allocated to the stems and leaves. The aboveground and belowground biomass of the tree species followed an isotropic growth pattern,except in the case of S. superba;(4) the models for regression estimation of seedling biomass of different tree species were mostly power-function models,followed by cubic polynomial models. There were differences in the allocation of biomass among different organs in the seedlings. Additionally,an isometric growth pattern between the aboveground and belowground biomass in seedlings was revealed. The regression estimation model for seedling biomass of each tree species can be used to estimate seedling biomass under similar or identical site conditions.