Abstract: By using the spatial series to replace time series,a test was conducted to study the properties of mineralizable carbon (MC) pool in 0～10,10～20 and 20～40 cm soil layers during re-vegetation on sloping-land with purple soils in Hengyang,Hunan Province. It observed that the contents of soil organic carbon (SOC) and MC as well as the carbon mineralization rate (MR) decreased with increasing soil depth but increased with the process of re-vegetation;MC/SOC increased with the re-vegetation process but decreased then increased and finally distributed evenly with increasing soil depth;The amount of cumulative released carbon and the carbon release rate increased with the process of re-vegetation,but the release rate decreased with increasing incubation time;qCO₂ decreased with increasing soil depth and the process of re-vegetation;The soil MC contents had a negative correlation with the litter existing biomass(r=-0.698^*) but positive correlation with the mass loss rate(r=0.915^**)(^*P<0.05,^**P<0.01). All the results indicated that soil habitat changed from strong interference at early stages to relative stability at late stages,and the soil carbon sequestration ability changed from small capacity and strong potential at early stages to large capacity and weak potential at late stages.

Key words: Carbon pool properties, Mineralizable carbon (MC), Re-vegetation, Purple soils, Soil organic carbon(SOC)

摘要： 本研究采用空间序列代替时间序列方法，研究衡阳紫色土丘陵坡地植被恢复过程0～10、10～20与20～40 cm土层土壤可矿化碳库特征。结果表明：恢复过程中土壤有机碳含量、可矿化碳含量和矿化速率随土层加深而减少，随恢复进程而增加；矿化率随恢复进程增加，随土层加深先减后增再分布均匀；累积矿化排放量及其速率随恢复进程增加，其速率随培养时间延长而减小；qCO₂值随恢复进程和土层加深而递减；土壤可矿化碳含量与凋落物现存量、质量损失率的相关系数r分别为—0.698^*和0.915^**（^*P<0.05，^**P<0.01）。研究表明，随着植被恢复进行，土壤生境由早期干扰强烈转向中后期日趋稳定，土壤固碳能力由早期差、潜力大转向中后期强、潜力小。

关键词: 碳库特征, 可矿化碳, 植被恢复, 紫色土, 有机碳