中文摘要：

由于桉树人工林可能导致土壤退化、肥力下降，为了评价人工种植桉树年限对当地土壤养分变化的影响。以不同种植年限桉树林 （１、５、10和 15年） 作为研究对象，探讨桉树种植年限对不同土层 （０～20、40～60、80～100ｃｍ）土壤养分的变化趋势。结果表明：相同种植年限不同土层 ｐＨ值在种植 ５年后０～20ｃｍ与 ４０～100ｃｍ相比较显著降低 ２１.６７％；１５年生桉树林土壤有机质含量随土壤深度增加；速效钾、有效磷和碱解氮都随土层深度增加呈降低趋势；有机质在 ０～60ｃｍ随种植年限增加而显著下降；速效钾各层都随种植年限增加而显著降低；有效磷在 ０～20ｃｍ随种植年限增加而显著下降，碱解氮累积量在 80～100ｃｍ随年限延长呈增加趋势。总之，不同种植年限桉树林均不同程度降低土层土壤的养分。

英文摘要：

Based on Eucalyptus forests soil degradation and fertility decline, the influences of Eucalyptus planting age on soil nutrients chang was evaluated. Different planting ages of Eucalyptus forest （ 1, 5, 10 and 15 a） were selected to analyze soil nutrients in different soil layer （0 -20, 40 -60, 80 - 100 cm）. The results showed that the soil pH value of 0 N 20 cm layer five years later significantly reduced by 21.67% compared with 40 - 100 cm, organic matter content increased with soil depth increase in 15 -year planting age, available potassium, available phosphorus and available solution nitrogen contents decreased with soil depth increase. The organic matter content in 0 -60 cm soil layer with the planting age showed dramatically decreased with increase in planting age, available K content reduced with increase in planting age, available phosphorus content in 0 -20 cm layer with the planting age has significant declined with increase in planting age, available nitrogen content increased with increase in 80 - 100 cm layer. In general, soil nutrient content of different layer decreased with increase in planting age of Eucalyptus forest to some extent.