杂种落叶松林下土壤变化规律的研究

Study on Change Rule of the Soil in the Hybrid Larch

以四种造林密度的杂种落叶松人工林为研究对象,与相同立地条件、相同林龄的长白落叶松林分、造林前的天然次生柞林林下的土壤营养成分进行对比分析。结果显示:次生柞林皆伐后营造杂种落叶松,19年后土壤的非毛管孔隙度变小,土壤的持水性能变差,pH值变小,土壤酸性增强,速效氮、速效钾、全氮、全磷、全钾含量均有大幅度的降低;林分密度越大,土壤酸化程度越高,造林密度2 500株/hm^2和3 300株/hm^2的林分,土壤结构、孔性、通水透气性相对较好,且透水性和持水能力比较协调,土壤中各营养元素含量较高;相同造林密度的杂种落叶松林分土壤结构、通气透水性及土壤中各营养元素含量相对高于长白落叶松。

Research on the four afforestation densities stand of Hybrid Larch. The comparison and analysis of soil nutrients under Larix Olgensis natural and secondary oak forest under before afforestation showed that: 19 years after Hybrid Larch were build under the secondary oak forest were cutted, the non-capillary porosity of soil decreases, the water holding capacity is worse, the p H walue decreases, the soil acidity is enhanced, the instant nitrogen, the instant potassium, the total nitrogen, the total phosphorus and the potassium content are all reduced greatly. The afforestation density larger, the soil acidity higher, The soil structure, porosity and water permeability of the stand of 2 500 N/hm^2 and 3 300 N/hm^2 are relatively good,the water permeability and water capacity are relatively harmonious, the cantent of various nutrient elements are higher. The soil structure, permeability and content of nutrients in the soil of Hybrid Larch were higher than that in the same afforestation density Larix Olgensis.