中亚热带四种森林土壤团聚体及其有机碳分布特征

选择中亚热带地区4种典型森林类型:杉木林、湿地松林、毛竹林和次生林4种森林土壤为研究对象,研究了森林类型对土壤不同发生层水稳性团聚体及其有机碳分布特征的影响。结果表明:不同森林类型对>5 mm和2~5 mm土壤团聚体含量影响显著(p<0.05),表现为次生林>杉木林>毛竹林>湿地松林,而在其他粒径无显著差异。0~30 cm土层内团聚体R0.25和MWD次生林显著高于其他人工林,杉木林次之,湿地松林和毛竹林最低,其他土层无显著差异。各森林类型同土层不同粒径团聚体中有机碳含量随粒径大小变化,团聚体粒径越小,有机碳含量越高。0~10 cm土层同粒径土壤团聚体有机碳含量从大到小依次是次生林、杉木林、湿地松林和毛竹林,而在其他土层各森林类型之间差异不显著。

Distribution of soil aggregates and SOC of aggregates under four forest types in mid-subtropics

This study was carried out on four typical forest types in middle subtropical zone: Chinese fir, slash pine, bamboo and secondary forest, to study the effects of forest type on soil water-stable aggregates and soil organic carbon (SOC) distribution characteristics. The results showed that the forest type had significant effects on soil aggregate contents of >5mm and 2-5mm size groups, which followed the sequence of secondary forest> Chinese fir> bamboo> slash pine (p<0.05). At 0-30cm soil layers, R0.25 and MWD in secondary forest were significantly higher than that in other forest types. SOC content in the same layer of the same forest type increased with the decrease of aggregate size. SOC contents of the same size aggregate group at 0-10cm layer decreased following the sequence of secondary forest> Chinese fir> slash pine> bamboo. There was no significant difference between secondary forest and plantations in other soil layers.