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以黑河上游祁连山中段青海云杉林为研究对象,分析了不同林区云杉林表层(0~20 cm)土壤有机碳的分布特征及其与气候因子、植被特征和土壤特性的关系。结果表明:祁连山中段3个林区青海云杉林表层土壤有机碳含量为寺大隆林区[(9.38±0.72)%]>西水林区[(7.81±0.43)%]>大河口林区[(6.06±0.30)%],土壤有机碳含量平均值为(7.41±0.28)%,变异系数为37.9%。土壤有机碳含量与海拔、土壤含水量、土壤全氮呈显著正相关关系,而与土壤pH值呈显著负相关关系。经主成分分析表明,海拔和土壤pH值是影响土壤有机碳含量的第一主成分,土壤全氮是第二主成分,云杉林密度是第三主成分,累计解释率为72.47%。
Taking the Picea crassifolia forest in the middle Qilian Mountains in the upper reaches of the Heihe River as the research object, the distribution characteristics of soil organic carbon in the surface layer (0 ~ 20 cm) of Picea mongolica forests in different forest regions and its relationship with climatic factors, vegetation characteristics and soil characteristics were analyzed. The results showed that the surface soil organic carbon content of Picea crassifolia forest in three forest regions in the middle Qilian Mountains was (9.38 ± 0.72)%> (Xiashi Shui Forest Region) [(7.81 ± 0.43)%]> Dahekou Forest Region [(6.06 ± 0.30)%], the average content of soil organic carbon was (7.41 ± 0.28)% and the coefficient of variation was 37.9%. Soil organic carbon content had a significant positive correlation with elevation, soil water content and soil total nitrogen, but negatively correlated with soil pH value. Principal component analysis showed that elevation and soil pH value were the first principal components that affect soil organic carbon content. Soil total nitrogen was the second principal component and spruce forest density was the third principal component with a cumulative explanation rate of 72.47%.