In order to explore the relationship between soil organic carbon(SOC) content and the four variables(including altitude, slope, bulk density and pH value), the distribution characteristics of SOC content along the altitudinal gradient ranging from 295 to 2 130 m in Wuyi Mountain Nature Reserve were analyzed and the regression model of SOC based on the main control factors was constructed. The results showed that, in the same altitude, the SOC content generally decreased with the increase of soil depth and its decreasing amplitude was also decreased. The SOC content ranging from 6.12 to 120.41 g?kg-1showed obvious surface assembly in the soil profile. The SOC content at the same soil depth generally increased with the increasing altitude, but its growth rate decreased accordingly. The SOC content was highly significantly positively correlated with altitude (P<0.01) and was negatively correlated with bulk density (P<0.01). There was significantly negative correlation (P<0.05) between SOC content and pH value only in the layer at the depth of 30-40 cm. The multiple linear regression model had higher goodness of fit than simple linear regression model for predicting SOC content. The combination of different factors can explain most of the variation of SOC in different soil layers with the explanation between 74.1% and 89.1%.%为探讨土壤有机碳含量与海拔、坡度、容重、pH值的相关关系,以武夷山国家公园5个不同海拔高度45个采样点的土壤为研究对象,分析了土壤有机碳含量沿海拔梯度的分布特征,并构建了土壤有机碳含量基于主控因子的回归模型.结果表明:同一海拔高度,土壤有机碳含量随土层深度的增加而降低,且其降幅也随之变小.土壤有机碳含量变化范围为6.12~120.41 g?kg-1,其在土壤剖面的分布具有明显的表聚现象;同一土层深度,土壤有机碳含量随海拔高度升高而升高,但其增幅则随之变小;不同土层有机碳含量与海拔和容重分别呈极显著(P<0.01)正相关和极显著(P<0.01)负相关;土壤有机碳含量与pH值在30~40 cm土层呈显著(P<0.05)负相关,其它土层不显著;土壤有机碳含量的多元线性回归模型拟合优度高于一元线性回归模型,不同因子组合能解释不同土层有机碳含量大部分的变异,解释量介于74.1%和89.1%之间.
展开▼
