Abstract: Based on the data of five tree species,larch(Larix)in northeast,Chinese fir(Cunninghamia lanceolata),Masson pine(Pinus massoniana)and oak(Quercus)in south,and poplar(Populus davidiana)in northwest,the three methods for calculating biomass conversion factors(BCF)were compared firstly.Secondly,the differences of mean BCFs between larch and Masson pine,and those between two types of Chinese fir in two regions were examined using hypothesis test.The results showed:(i)it is suitable to use arithmetic mean method for calculating the mean BCFs;(ii)the BCFs of broadleaved species are larger than those of coniferous species;(iii)the mean BCFs of larch and Masson pine are not different significantly,while those of two Chinese fir types are different significantly.

Key words: biomass conversion factor, hypothesis test, larch, Masson pine, Chinese fir