马尾松人工幼林土壤肥力变化及其综合评价研究

Comprehensive evaluation on soil fertility variations in Pinus massoniana young plantation

通过分析广西环江县桉树林及砍伐后种植马尾松和荒地的土壤化学性质,运用灰色关联分析方法,研究和评价马尾松和荒地取代桉树后土壤肥力变化状况。研究结果显示:取代桉树林后,4.0龄马尾松和荒地的土壤碱解N、有效P、速效K、交换性Ca和有效Zn有所提高,土壤pH值有所改善,而全N、全P、全K、交换性Mg和有效Cu有所减少。0～20 cm层土壤有机质和有效B有所降低,20～40 cm层的反而有所提高。不同林龄马尾松和荒地的土壤综合肥力普遍较差。造林4年后,同土层马尾松林的土壤综合肥力低于荒地。除4.0龄荒地0～20 cm层的土壤综合肥力基本无变化外,其他4.0龄马尾松和荒地土壤综合肥力都有不同程度退化,而以4.0龄马尾松20～40 cm层的土壤肥力退化最严重。

The soil chemical characteristics ofPinus massoniana planted in the same land by cutting Eucalyptus forest and wasteland in Huanjiang county of Guangxi province were analyzed, the land＇s soil fertility variations were evaluated. The results show that after P. massoniana substituted Eucalyptus, the content of alkaline solution N, effective P, available K, exebangeable Ca and effective Zn in forest soil of 4-year-old P. massoniana stand and wasteland increased, the pH value was also raised compared to the previous, however, total N, total P, total K, exchangeable Mg and effective Cu decreased; the contents of organic matter and effective B decreased in 0 -20 cm soil layer, but that of in 20- 40cm soil layer increased; the soil integrated fertility was general poor in different age-grades P.massoniana forests and wasteland; after 4 years growth, soil integrated fertility of same soil layer ofP. massoniana was lower than wasteland; except the soil integrated fertility of 4 age wasteland was no any variation in 0 - 20cm soil layer, that of the other 4 age P. massoniana and wasteland degraded in various degrees, while the soil fertility in 4 age P massoniana forest soil in 20 -40 cm layer degenerated most seriously.