科尔沁沙地樟子松疏林草地土壤有机碳及其稳定性特征

目的]探讨科尔沁沙地半干旱区樟子松疏林草地土壤有机碳及其稳定性。方法]通过分析林内0～5、5～10、10～20和20～30cm层土壤有机碳(SOC)、土壤微生物量碳(MBC)以及土壤易氧化有机碳(Clab)含量,揭示樟子松疏林草地SOC含量及其稳定性。结果]樟子松疏林草地SOC含量随土层深度的增加而降低,由表层(0～5 cm)的6.77 g/kg降到深层(20～30 cm)的3.51 g/kg,下降了约48%;MBC在土壤空间分布上表现为先降低后增加,Clab含量呈相同的变化趋势。结论]随着土层深度的增加,樟子松疏林草地Clab含量升高,表明樟子松疏林草地SOC的稳定性随土壤深度的增加而降低。

Carbon Stock and SOC Stability in Soils of Pinus-sylvestris Scattered Grassland in Horqin Sandy Land

Objective] To explore the soil organic carbon and its stability of semi-arid Pinus sylvestris woodland grassland in Horqin sandy land.Method] The soil organic carbon（SOC）,soil microbial carbon（MBC）,oxidation of labile carbon（Clab） content in soil depth of 0-5 cm,5-10 cm,10-20 m and 20-30 cm were determined.And soil organic carbon content and stability was revealed.Result] The results showed that the soil organic carbon content decreases with the increase of soil depth,in the surface layer（0 to 5 cm） is 6.77 g/kg,deep（20 to 30 cm） is 3.51 g/kg,decreases by about 48%.MBC in the soil spatial distribution shows first decreases and then increases,and Clab has the same trend.Conclusion] Visible with the increase of soil depth,Pinus-sylvestris woodland grassland soil easily decomposed carbon increase,the stability of soil organic carbon decreases with soil depth increase.