辽东山区原始红松混交林土壤有机碳及其影响因素研究

Soil organic carbon and its impact factors in original Pinus koraiensis mixed forest in eastern Liaoning mountainous area

以辽东山区原始红松混交林为研究对象，对比分析了不同树种组成下原始红松混交林土壤有机碳含量的差异，研究了土壤有机碳与土壤属性因子和植被覆盖因子的相关关系，并研究了土壤碳密度的分布规律。结果显示，3种原始红松混交林土壤有机碳含量均随着剖面深度的增加而降低；0～10cm土层深度土壤有机碳含量为红松阔叶林〉阔叶红松林〉针阔混交林，表层土壤有机碳主要来源于枯落物层的分解，表层土壤有机碳的特征表明原始红松混交林树种构成不同，潜在地影响着生态系统内的碳循环。对土壤属性因子而言，碳氮比与有机碳含量呈极显著的正相关关系，而容重、pH值呈显著的负相关关系；对植被覆盖因子而言，枯落物有机碳、全氮、碳氮比与土壤有机碳含量则无相关关系；0～100cm深度内红松阔叶林的土壤碳密度最大，为181．4t/hm^2，针阔混交林次之，为180．56t／hm^2，阔叶红松林最小，为150．78t／hm^2，且接近70％的土壤碳储存集中在40cm以上的土层内。旨在为揭示原始红松混交林对土壤有机碳的影响因素和探索我国原始红松混交林土壤碳分布格局提供科学依据。

In this paper, we analyzed the soil organic carbon content in the original Pinus koraiensis mixed forest which contained different proportion of Pinus koraiensis, broadleaved tree species and other coniferous tree species. Correlation analysis was conducted for studying the relationship between soil organic carbon and soil properties, and the relationship between vegetation factors. And the soil carbon density distribution characteristics were studied as well. It showed that the soil organic carbon content of three original Ko- rean pine mixed forest were decreased with the increase of soil depth; soil organic carbon conlent of 0-10 cm soil depth was： Pinus ko- raiensis broad-leaved mixed forest〉 broad-leaved Pinus koraiensis mixed forest〉 coniferous broad-leaved mixed forest, surface soil organic carbon mainly comes from the decomposition of litter layer, surface soil organic carbon characteristics shows that the original Pinus kororaiensis mixed forest composition of different tree species have potential to affect the ecosystem carbon cycle. Refer to the soil properties, C： N and organic carbon content have extremely significant positive correlation with soil organic carbon content, and the bulk density, pH value have significant negative correlation relationship with soil organic carbon content; Refer to vegetation coverage factors, organic carbon, total nitrogen, C： N all have no relationship with soil organic carbon content; soil carbon density of P/tins koraiensis broad-leaved mixed forest of 0-100 cm soil depth was the largest（ 181.4 t· hm^2）, coniferous broad-leaved mixed forest was the second （180.56t· hm^2）, broad-leaved Pinus koraiensis rrfixed forest was the smallest （150.78 t· hm^2）, and it accounted by nearly 70% of soil carbon stored in the depth of 0-40cm soil. In order to reveal the influence factors of soil organic carbon in original Pinus horaiensis mixed forest and to provide a scientific basis for exploring the original Pinus koraiensis mitxed forest soil carbon distribution pattern.