不同深度土壤中氮素的空间变异研究

Spatial Variation of N in Different Depth Soil

对供试区分析土壤中的氨态氮和硝态氮含量,用区域化变量理论和半方差函数分析,研究结果表明不同深度土壤中氨态氮和硝态氮含量具有空间变异性,均属于中等程度变异。通过对其半方差函授进行拟合,其变异程度主要由土壤本身的空间结构引起,不同深度土壤中氨态氮和硝态氮含量的空间相关尺度不同。

NH4^＋-N and NO3^--N in surface soil （10-15 cm） and deep soil （35-40 cm） are measured in the study area. The experi- mental data is analyzed by the theory of regionalized variable theory and semi-variance function. The results show that NH4^＋ -N and NO3^--N in different depth soil has spatial variation, which belongs to middle extent variation. Through fitting the semi-variance func- tion, it is found that the variation extent is caused by spatial structure and the space correlative scale of NH4^＋ -N and NO3^--N in different depth soil is different.