燕山北部华北落叶松人工林与杨桦天然次生林土壤碳密度的比较

摘要

Soil organic carbon content (SOCC) of larch plantation and natural secondary pop-lar-birch forest in west region of Yanshan Mountains was studied in this paper for under-standing the effects of afforestation over soil organic carbon stock .The results showed that SOCC of larch plantation ( 30 .45 g/kg ) was higher than that of secondary poplar-birch forest ( 28 .45 g/kg ) .The SOCC of the both forests decreased with the soil depth .At the same time ,there was significant difference of SOCC between adjacent layers in upper soil but not in lower soil by variance analysis .It was concluded that under proper afforestation meas-ures and less human disturbance ,the plantation could maintain high soil organic carbon stock as natural forests .%为了了解人工造林过程对土壤碳储量的影响，对燕山西部山地常见的华北落叶松人工林和杨桦天然次生林土壤有机碳含量进行了研究。结果表明，华北落叶松人工林和杨桦天然次生林的土壤剖面平均有机碳含量分别为30．45 g/kg和28．45 g/kg ，二者没有明显差异；2种林分的土壤有机碳含量均随着土层深度的增加而降低，下降幅度则随深度的增加逐渐减缓，表层土壤对土壤的碳存储贡献更大。总的来看，土壤有机碳含量在深层（30 cm以下）相邻土层之间差异不显著，说明深层土壤中，有机碳含量变化较小。由以上结果可以得出结论，在造林措施适当、人为干扰较少的条件下，人工林同样可以维持与天然林相近的较高的土壤碳储量。