桉树不同更新方式效果与效益分析

在福建岩溪国有林场开展桉树2代炼山植苗造林与不炼山萌芽更新2种不同更新方式的对比试验,通过对炼山植苗造林与萌芽更新的林分生长量以及经济效益的分析,结果表明:3.5年生炼山植苗造林的林分平均树高、胸径、材积分别比萌芽林分提高3.1%～13.1%、1.7%～11%和7.1%～40.5%,蓄积量提高15.9%～56.9%;6年生时其经济效益提高44.3%,成本增加31.6%,投入产出比降低9.5%;炼山植苗造林生长潜力大,可培育大径材。而萌芽更新早期生长快但衰老也快,生长后劲不足且抗风性差;但对林地及周围环境影响较小。生产上,应根据不同的立地条件和投资主体,选择适宜的桉树更新方式,从而满足木材需求的同时保持林地的可持续利用。

Effects and Benefits Analysis of Different Regeneration Patterns of Eucalyptus

The comparison between two different regeneration patterns(controlled burning afforestation and sprout forestation) of 2nd generation of Eucalyptus was conducted in Yanxi National Forest Farm.Through the analysis of stand growth amount and economic benefits of controlled burning afforestation and sprout forestation factors,it was found that 3 and a half years old experimental forest's average height,dbh,forest volume stocking were in sequence 3.1%～13.1%,1.7%～11%,7.1%～40.5% and 15.9%～56.9% higher than the latter one.Economic benefit was more than 44% higher,while only 31.6% costs increased.The input-output ratio decreased by 9.5%(after 6 a).Burning afforestation brought the big growth potential after fostering large-diameter timber.The sprout forestation was fast growing and soon old,it lacked stamina with poor wind resistance.The latter regeneration pattern had little bad effects on forestlands and surroundings;Therefore,it was suggested that different regeneration patterns should be chosen according to local condition and investments to meet the wood demand and obtain forestland sustainable application.