刚果12号桉无性系人工林养分曲线

NUTRIENT CURVE OF EUCALYPTUS ABL12 PLANTATION

应用常规方法 ,在雷林NPK复混肥和HYDRO NPK复合肥刚果 12号桉树无性系人工林试验区采样分析 ,结果表明 :桉树器官氮、磷、钾的浓度存在显著差异 ,顺序为 :叶 >枝 >皮 >根 >干 ;树体养分的平均浓度C随林龄t增大而降低 ,降低速率与施肥强度Q相关 ;桉树林养分吸收的总量X随t和Q增大而增大 ,养分吸收速率 (dX dt)随t增大而降低 ,说明桉树生长早期养分供给的重要性。养分吸收曲线可反映不同生长时期林木吸收养分的相对强度 ,给出达到相对应生长量的净养分需求量 ,在林木营养动态管理中具有重要理论和实践意义。

Samples were taken from Eucalyptus ABL12 plantation fertilized respectively with Leilin NPK mixture and Hydro NPK complexes using methods commonly applied. The analytical results showed that there were significant differences in the concentration of nitrogen, phosphorus and potassium in different organs of eucalyptus tree in the order:leaf>branch>bark>root>stem. The average nutrient concentration in eucalyptus (C) decreased with tree age( t ) increasing, and its decreasing rate related to fertilization levels ( Q ). The total quantity of nutrient uptake by plantation( X ) increased with t and Q increasing, while nutrient uptake rate (d X /d t ) decreased with t increasing. This indicated high importance of eucalyptus stand nutrition in its early growing period. The nutrient uptake curve could be used for determining both the relative intensity of nutrient uptake and the net quantity of nutrient demand relating to stand growth at different stand growing stages, and was thus of high value both in theory and in practice in the dynamic management of stand nutrition.