尾叶桉幼林施肥效应的研究*

A Study of Fertilization Effect on Young Trees of Eucalyptus urophylla

There have been obvious fertilization effects of fast growth in the early stage for young trees of E.urophylla if applying enough amount of base fertilizer before planting.A trial of amount of fertilizer applied and fertilizer ratio for young trees of E.uro-phylla has been carried out in 1992. The results show that the effects of mixing N,P and K fertilizer used as base fertilizer are significant. The mean tree height and DBH of nine fertiliz-er treatments at the age of 23-month-old in the trial are 6.43 m and 6.86 cm respectively,and the mean tree height,DBH and volume per hectare for the ninth treatment(N100P150K50)are re-spectively 7.73 m,8.0cm,and 26.335 m3,which are respectively 293.92%,408.16%and 4 931. 6%of the control treatment (no fertilizer treatment) which is of 2.63 m tree height,1.96 cm DBH and 0.534 m3 for volume per hectare. The audio-visual analysis of tree height, DBH and volume per hectare show that the N100P150K50 treatment is the optimum recipe.The contents of nutrient elements in foliage are also obviously different among the treatments.