乌拉山天然油松林土壤碳密度空间异质性研究

Study on Spatial Heterogeneity of Wulashan Natural Pinus Tabulaeformis Forest Soil Carbon Density

乌拉山地处干旱草原向荒漠过渡的中间地带，是我国油松自然分布的北界。针对乌拉山地区天然油松林处于过渡带的独特地域性特点，通过室内土壤有机碳测定和统计学分析，结果表明：（1）乌拉山天然油松林土壤土层厚度为1m的土壤碳密度总体上在70．26—325．0thm。之间，土壤碳密度在空间上变异性较大；（2）土壤中的有机碳随土壤深度增加呈降低的趋势，有机碳主要集中在0—40em土层中，占总有机碳的67．5％；（3）不同坡位之间，土壤碳密度的变异程度为坡下〉坡上〉坡中，不同坡位之间土壤碳密度存在显著性差异；（4）不同坡向之间，土壤碳密度变异程度为阴坡〉阳坡，不同坡向之间土壤碳密度存在显著性差异。研究结果可为合理评测森林土壤碳密度在剖面上的分布特征和空间异质性有着重要意义。

Wulashan is the north boundary of Pinus tabulaeformis distribution in china. According to the distribution characteristics of pinus tabulaeformis, through the soil organic carbon measurement statistics analysis results show that： （1） The Wulashan natural pinus tabulaeformis forest under lm soil layer thickness of soil carbon density overall in 70.26 t hm-2- 325.0 t hm-2, soil carbon density has large variability in space; （2） The soil organic matter in the soil was decreased with the increased of soil depth, soil organic matter mainly concentrated in the 0 - 40 cm soil layer, which accounts for 67.5% of the total organic matter. （3） Between different slope positions, the order of the degree of variability of soil carbon density is ＂the under slope 〉 the upper of the slope 〉 the middle slope＂, soil carbon density have significant differences between the different slope positions. （4） Between different slope directions, the shady slope soil carbon density variability is larger than the sunny, soil carbon density have significant differences between the different slope directions. The research results can be used for reasonable evaluation forest soil carbon density in profile distribution characteristics and spatial heterogeneity has important significance.