In order to explore the effects of different restoration approaches on soil aggregates’ formation and it’s cycle carbon of severely burned area in Greater Xing’an Mountains

the artificial restoration (Larix gmelini and Pinus sylvestris var. mongolica) and the natural regeneration of forest in Greater Xing’an Mountains after the severely burned in 1987 respectively were chosen as the research object and analyzed the distribution features of organic carbon

microbial biomass carbon and K2SO4-extractable carbon in soil aggregates under different restoration approaches. The results showed that: (1) There were significant difference (P＜0.05) for the contents of organic carbon

microbial biomass carbon and K2SO4-extractable carbon in soil aggregates among different forest types

which the characteristics were Larix gmelini plantation＞natural secondary forest＞Pinus sylvestris var. mongolica plantation. (2) Under different vegetation restorations

soil organic carbon and microbial biomass carbon presented an increasing trend along with increasing of particle size of aggregate

and the large aggregates were significant higher amounts of both the soil organic carbon and microbial biomass carbon than the micro aggregates（P＜0.05）

the K2SO4-extractable carbon mainly distributed in the 1~0.5 mm particle size and larger size aggregate. (3) The organic carbon and microbial biomass carbon in soil aggregates mainly distributed in soil surface layer (0—5 cm)

which the contents decreased with the increase of soil depth. Except ＞2 mm and 2～1 mm aggregates

the contents of K2SO4-extractable carbon in soil aggregates presented a decreasing trend along with the increase of soil depth. (4) Microbial biomass carbon had significant positive correlations (P＜0.01) with soil organic carbon and K2SO4-extractable carbon

revealing that microbial biomass carbon had close relationship with soil organic carbon and K2SO4-extractable carbon.