北京松山自然保护区不同母质油松林土壤氮、磷、钾含量垂直分布

Vertical distribution patterns of nitrogen, phosphorus, and potassium in Chinese pine forest soils developed from different parent materials in Songshan Mountain Nature Reserve, Beijing of China

以北京市松山自然保护区同海拔油松林下两种母质(花岗岩和石灰岩)上发育的土壤为对象,研究了土壤的全氮、有效磷、速效钾含量在剖面的垂直变化.结果表明:花岗岩母质发育的土壤0～20cm土层的全氮、有效磷和速效钾含量分别为1.61～2.35g·kg-1、5.84～10.74mg·kg-1和39.33～93.66mg·kg-1,石灰岩母质发育的土壤分别为1.69～2.36g·kg-1、4.45～8.57mg·kg-1和60.66～124.00mg·kg-1.两种母质发育的土壤0～10cm土层的全氮、有效磷和速效钾含量均最大,且与各土层之间差异均极显著,并随土层深度的增加而下降,说明土壤全氮、有效磷和速效钾含量的分布有很强的表聚性,而且石灰岩母质发育的土壤的表聚性更强.对同土层土壤进行配对t检验,全氮含量在各土层之间无显著性差异,有效磷含量在0～10cm土层差异极显著,速效钾含量在10～20cm土层之间差异显著.

Taking the soils developed from two kinds of parent materials （granite and limestone） under Pinus tabulaeformis forest at the same altitude in Songshan Mountain Nature Reserve of Bei- jing as test objects, this paper studied the vertical distribution patterns of soil total nitrogen, available phosphorus, and available potassium.＇ The soil developed from granite had the total nitro- gen, available phosphorus, and available potassium contents being 1.61-2.35 g·kg^-1, 5.84- 10. 74 mg·kg^-1 , and 39.33-93.66 mg·kg^-1 , while that developed from limestone had the total nitrogen, available phosphorus, and available potassium contents being 1.69-2. 36 g ·kg^-1, 4.45-8.57 mg·kg^-1, and 60.66-124.00 mg·kg^-1, respectively. The total nitrogen, available phosphorus, and available potassium contents in the two soils were the highest in 0-10 cm layer, decreased with increasing depth, and had significant differences between different layers, showing that the soil total nitrogen, available phosphorus, and available potassium had a strong tendency to accumulate in surface layer. Such a tendency was more obvious for the soil developed from lime- stone. The paired t-test for the two soils indicated that the total nitrogen content in different layers had no significant difference, whereas the available phosphorus content in 0-10 cm layer and the available potassium content in 10-20 cm layer differed significantly.