天山云杉林土壤有机碳含量沿海拔梯度变化

Distribution Characteristics of Soil Organic Carbon of Spruce Forest along Elevation Gradients in Tianshan Mountains

【目的】研究天山中部地区海拔对土壤有机碳含量的影响,研究区域尺度上土壤有机碳含量随海拔梯度变化,以及土壤其他因子之间的相关分析,精确估算森林生态系统土壤有机碳库。【方法】以新疆天山三个样区云杉林为对象,利用单因素方差分析和最小显著差异法等统计分析方法,研究不同海拔各土壤层有机碳含量垂直分布、积累特征及其与土壤全氮、全磷和pH值的关系。【结果】不同海拔梯度下,不同林区土壤有机碳含量随着土层深度呈逐渐减少的趋势;海拔梯度对有机碳含量的影响比较明显,尤其是2 000和2 200 m处的有机碳含量最高,1 800 m处次之,而2 400 m处最低;【结论】三个林区有机碳含量在不同土层厚度中随海拔高度的增加无明显规律;土壤各土层有机碳含量与全氮含量为极显著正相关和土壤全磷含量为显著正相关,而与土壤pH值为弱负相关关系。

【Objective】It is of great significance to develop the correlation analysis of soil organic carbon content with elevation gradient and other soil factors in regional scale,the research of which might have an important guiding meaning for accurate estimates of our forest ecosystem soil organic carbon pool.【Method】In order to study the effect of altitude on soil organic carbon content in the middle of Tianshan Mountain,this paper studied the soil organic carbon content in three sample areas of Tianshan Mountain,Xinjiang,and used single factor variance analysis and minimum significant difference method to analyze the soil organic carbon content. The vertical distribution and accumulation of organic carbon in different soil layers at different elevations and their relationship with soil total nitrogen,total phosphorus and PH value were studied.【Result】The results showed that the soil organic carbon content in different forest regions decreased gradually with the depth of soil layer at different elevation gradients,and the influence of elevation gradient on organic carbon content was obvious,especially at 2,000 m and 2,200 m,the highest content of soil organic carbon was 1,800 m,especially at 2,000 m and 2,200 m. The lowest was at 2,400 m. 【Conclusion】In three forest areas,there was no significant correlation between soil organic carbon content and total nitrogen content,and the soil organic carbon content was positively correlated with total nitrogen content and soil total phosphorus content was significantly positively correlated,but had a weak negative correlation with soil pH value.