退化红壤植被恢复中表层土壤微团聚体及其有机碳的分布变化

采用超声波分散分离提取土壤微团聚体 ,通过测定有机碳含量、分析碳稳定性同位素 ,研究了退化红壤在植被恢复下土壤微团聚体粒组分布与有机碳分布 .结果表明 ,植被恢复尤其是豆科 -禾本科植物轮作较快地增加了土壤有机碳储存 ,这种碳存储表现为 2～ 0 .2 5mm团聚体的建成 ,并对微团聚体有机碳的稳定性同位素组成分异产生影响 .本文揭示了我国广泛实施的区域土壤治理和植被恢复措施促进了土壤碳截存 ,可以认为显著地贡献于陆地系统对大气CO2 的汇作用

Changes in organic carbon storage in aggregates of the surface horizon in a degraded Paleudlt upon vegetation recovery

Soil aggregates of a Paleudlt in Nanchang, Jiangxi upon vegetation recovery for years were separated by ultrasonic dispersion, and the carbon contents and the natural abundance of carbon isotope were determined. The soil organic carbon storage was increased at the rate of 0.3 to 0.5 gkg -1 yr -1 and the increase was most obvious in the size fraction of 0.25 - 2 mm. The carbon isotope composition was also changed to some extend. The findings indicated that nationwide resilience practice for vegetation recovery launched since 1980's reinforced soil organic carbon storage and sequestration, enlarging the sink for atmospheric carbon dioxide.