施肥位点对尾巨桉幼林生物量分配及养分利用率的影响

以尾巨桉为研究对象,对其幼林进行培育,研究不同施肥位点对尾巨桉幼林生物量、养分分配及养分利用率的影响.结果表明:单位点穴施更促进根系生长,但是双位点穴施对树皮、叶片、树干、树枝和总生物量累积效果更好.养分分配除树根各处理磷素累积量差异不显著外,其他部位各养分累积量在各处理间均差异显著.不同处理叶片养分含量显著高于其他部位,且氮含量高于磷、钾含量.虽然处理Ⅱ各元素养分利用率及各部位养分累积利用率普遍优于处理Ⅰ,但差异均不显著.对尾巨桉施肥位点的研究处于初期阶段,还有待进一步探讨.

Effects of Number of Fertilization Sites on Biomass,Nutrient Distribution and Nutrient Utilization of Eucalyptus urophylla ×E. grandis

In this study the biomass, nutrient distribution and nutrient utilization of Eucalyptus urophylla × E. grandis plantations grown with the same level of fertilizer applied to trees in varying spatial patterns were investigated. Results obtained showed: single point fertilizer application was more favorable for root growth, compared to double-point application that was more favorable for the leaf, stem and shoot growth as well as for total biomass. Except for phosphorus accumulation, differences among treatments were significant for foliar levels of the other two key nutrient elements (nitrogen and potassium) and nutrient contents in leaves were higher than in other parts. Although the nutrient utilization rate and nutrient accumulation rate of each element in treatment Ⅱ were generally better than those in treatment Ⅰ, the differences were not significant. The research reported in this paper is still in preliminary stages and longer-term results and more detailed analyses are required.