桉树人工林土壤肥力变化及其综合评价

Variation of Soil Fertility in Eucalyptus Plantation and Its Soil Fertility Comprehensive Evaluation

通过分析桉树人工林和对照的土壤化学性质,运用灰色关联分析方法,研究和评价桉树人工林种植前后的土壤肥力变化状况。研究结果表明,除4.0年生对照处理的土壤碱解N和有效B含量比造林前有所提高外,其余各项营养指标含量均比造林前低,且大部分营养元素处于缺或极缺水平。不同林龄桉树和对照的土壤综合肥力明显比造林前低,土壤肥力普遍较差。其中,造林前的土壤综合肥力最高,而3.5年生桉树的土壤肥力退化最严重,且4.0年生桉树的土壤肥力低于同期的对照处理。

The study was carried out in a Eucalyptus plantation and a contrast set up in Guangxi Paiyang- shan State Forest Farm, and the soil chemical characteristics were analyzed. A grey correlation analysis was used to evaluate the soil fertility status before and after the planting Eucalyptus plantation. The results showed that except 4. 0 years old contrast treatment with an increase of alkaline solution N and effective B in forest soil after afforestation, the rest of the nutrition indicators reduced after afforestation, and most of them were in a low or very low level. For Eucalyptus plantations at different ages and the contrast, the soil integrated fertility was significantly lower after afforestation, and was generallypoor. Among them, the soil integrated fertility was the highest before planting; 3.5 years old Eucalyptus plantation decreased the most seriously; the soil fertility of 4. 0 years old Eucalyptus plantation was lower than the same aged con- trast. The research results could provide scientific and reasonable theories for formula fertilization of Eu- cal3otus plantation.