施肥对乡土树种川滇桤木幼林生长特征的影响

对1a生川滇桤木幼林进行施肥试验。结果表明，施肥对川滇桤木苗木的幼林生长有显著影响。1a生幼林施肥处理下的苗高、地茎和冠幅生长量分别比对照增长13．01％、20．37％和11．52％，且差异显著；2年后肥料效应对地径影响显著，比对照增长21．13％；对苗高、冠幅的作用减弱，分别比对照增长6．97％和7．20％。1a生和2a生幼林施肥处理下，茎叶鲜重、茎叶干重、根系鲜重、根系干重的平均生长量均明显高于未施肥处理的对照，且差异显著；叶片相对含水量也高于对照，且1a生幼林茎叶的相对含水量差异显著，而2a生幼林差异不显著。2a生川滇桤木新造幼林根系从0．2～1．5cm范围内均有分布，其中0．20～0．45cm范围根系最多；0．46～0．59cm范围内次之；0．60～0．99cm和1．00～1．50cm范围内最少。

Effect of Fertilizer on Growth Characteristics of Alnusferdinandi-coburgii Young Plantation

Fertilization experiments were made to annual Alnusferdinandi-coburgii young plantations. The results showed that there were significant effects of fertilizer on Alnusferdinandi-coburgii young planta- tions. The annual growth increments of one year tree seedling height, ground diameter and crown width were increased by 13.01% , 20.37% and 11.52% respectively compared with control, the differences were significant; the fertilizing effect on biennial plantations was significant in terms of ground diameter, which increased 21.13% compared with control; but the fertilizing effects on seedling height and crown width were not significant, increasing at only 6.97% and 7.20% respectively compared control. When fertilized, the average increment of stem-leaf natural weight, stem-leaf dry weight, root natural weight, root dry weight of one and two year Alnusferdinandi-coburgii young plantations were significantly higher than control; the relative water content of the leaf was also higher than control, which the difference was significant in one year young plantations, and not as significant as two year young plantations. In two yearyoung plantations of Alnusferdinandi-coburgii, the root distributed in the scope of 0. 2-1.5 cm, the root distributed scope order followed as 0.20 - 0.45 cm. 6-0.59 cm, 0.60-0.99 cm and 1.00-1.50 cm.