关键词: 退耕植茶, 土壤团聚体, 团聚体稳定性, 无机磷组分

Abstract: In order to understand the change of soil carbon storage during natural restoration succession of coniferous-broadleaved mixed forest communities in Changbai Mountains, five successional stages, including birch young forest, birch middleaged forest, birch mature forest, mature broadleaved Korean pine forest and old broadleaved Korean pine forest, were chosen using the temporalspatial substitution method, to study the soil organic carbon (SOC), readily-oxidized organic carbon (ROC), microbial biomass carbon (MBC) and particulate organic carbon (POC) contents. The results showed that SOC, MBC, ROC, POC and soil total nitrogen, total phosphorus and carbon to nitrogen ratio (C/N) all increased firstly and then remained stable from early to late succession. The contents of SOC, MBC, ROC and POC were significantly decreased (P<0.05) with the increasing soil layer depth. ROC/SOC and POC/SOC ranged between 12.91%-47.95% and 14.21%-69.46% in the five successional stages, respectively. The correlation analysis showed a significant positive correlation (P<0.01) between MBC, ROC, POC and SOC, and a significant positive correlation (P<0.01) between SOC, MBC, ROC, POC and total nitrogen, total phosphorus, carbon to nitrogen ratio. Our results provide data support for clarifying soil organic carbon stability and carbon sequestration potential during the succession of the birch forest.

Key words: aggregate stability, inorganic phospho-rus fraction, returning from cropland to tea, soil aggregate