不同模型在土壤剖面有机碳垂直分布中的应用∗

摘要

Exponential model, power function model, logarithmic model and S⁃function model were used to fit the profile distribution of soil organic carbon based on Nong′an 50 species of soil organic carbon data profiles. The research results show that fitting effect of S⁃function model on soil organic carbon profiles was the best, R2 of which reached 0�9 basically. Fitting effect of power function mod⁃el was the worst, R2 of which stabilized at 0�77. On the basis of the four models, organic carbon density at 1 m depth of each point was calculated. Organic carbon density of power function model, exponential model and logarithmic model is slightly higher, and that of S⁃function model is slightly lower . Appropriate model is needed in describing vertical distribution of organic carbon in soil profile of an area and it can only be decided based on the analysis of data of representative soil profiles.%利用指数模型、幂函数模型、对数模型和S函数模型，以农安县50个土壤剖面有机碳数据为基础，拟合了土壤有机碳剖面垂直分布。研究结果表明：S函数模型对土壤有机碳剖面分布的拟合效果最好，R2约达到0�9。拟合效果最差的是幂函数，R2稳定在0�77。在4种拟合模型的基础上，计算了各点1 m深土壤剖面的有机碳密度，幂函数模型、指数模型和对数模型估算的有机碳密度偏高，S函数模型偏低。描述某地区土壤剖面有机碳垂直分布需要选择适当的模型，依据一定代表性土壤剖面数据进行分析后方能确定。