子午岭植被恢复过程中土壤团聚体有机碳含量的变化

土壤有机碳是土壤团聚体形成的重要胶结剂之一，土壤团聚体分布影响有机碳含量及其稳定性。对子午岭植被恢复过程中团聚体有机碳含量变化的研究结果显示：相对于农田，植被恢复可增加土壤各个粒径团聚体有机碳含量．同时增加不同层次土壤团聚体有机碳含量。就粒径而言，虽然各个植被下〈0．25mm土壤团聚体有机碳含量最低，植被类型变化对土壤团聚体有机碳含量影响最大的是〈0．25mm粒径，辽东栎林地〈0．25mm土壤团聚体有机碳含量是农田〈0．25mm团聚体有机碳含量的3倍；其次，植被类型对〉5mm团聚体有机碳含量影响较大，辽东栎、早期森林、灌丛、草地和弃耕地土壤〉5mm团聚体有机碳含量比农田土壤〉5ram团聚体有机碳含量高149％，209％，104％，62％，10％。说明植被演替可增加土壤团聚体有机碳含量，但首先是增加较大粒径团聚体的有机碳含量；随着植被的进一步演替，小粒径团聚体有机碳含量也相应的增加，这部分有机碳是稳定的，说明植被恢复增强了土壤的碳汇功能。

Changes of Soil Aggregate Organic Carbon During Process of Vegetation Restoration in Ziwuling

The organic carbon binding micro aggregates and other particles together into macro aggregate is believed to be physically protected from decomposition,which was more stable than the carbon in macro aggregates.The object of this article was to study the distribution of soil organic carbon in aggregates,and to know whether the soil can sequestrate more stable carbon and decrease emission CO_2 or not since vegetation restoration.The results showed that stabile aggregates(>0.25 mm) were increased in soil,and soil organic carbon in different diameter aggregates was increased since vegetation restoration.Though the content of soil organic carbon in <0.25 mm were least under all vegetations,TOC in <0.25 mm in Quercus liaotungensis was three times than that of cropland.The content of soil organic carbon in >5 mm aggregate in vest land,herbage,shrub,early forest,Quercus liaotungensis were higher 149%,209%,104%,62% and 10% than that in cropland.There were much more young organic carbon in macro aggregate since vegetation restoration,and then there was much soil organic carbon in micro aggregates with vegetation succession.Soil organic carbon in micro aggregates is stable,so soil can sequestrate more stable carbon since vegetation restoration.There were positive correlation between the mean weight diameter of aggregate and the content of soil aggregate organic carbon.We can draw a conclusion that thefunction of soil as a carbon pool was strength since the restoration of vegetations in Ziwuling region.