摘要
为探索适合南方林区瘠薄土壤的毛红椿混交改造模式,对改造后的毛红椿纯林(CK)及无患子×毛红椿(SsT)、观光木×毛红椿(MoT)、火力楠×毛红椿(MmT)和壳菜果×毛红椿(MlT)混交改造林进行1~8 a的生长调查,分析比较其林分结构、林地土壤和毛红椿的年生长动态及其生长差异。结果表明:混交改造后,林分结构趋于复杂,林地土壤得到不同程度地改良,改良效果为MoT>MmT>MlT>CK>SsT。不同混交改造林林分幼龄期(4~8 a)的毛红椿生长有不同程度的差异,其胸径和树高生长基本呈“快-慢”的变化趋势,且表现为树高的生长节律优先,MoT和MmT混交改造林分尤为明显。毛红椿早期耐阴,约在4 a后,混交改造对林分郁闭度产生影响,从而形成较合理的时空格局,并有利于毛红椿大径级材的培育。与CK相比,不同混交改造林分的毛红椿生长有促进、抑制性可能、后期抑制3个层次的生长效应,且随林龄增长均保持一致。其中,MoT和MmT混交改造林分对毛红椿的促进生长效应优,8 a林龄毛红椿的平均胸径、平均树高、单株材积分别比CK提高了19.8%、22.1%、71.8%和25.7%、20.2%、85.1%;抑制性可能层次为SsT混交改造林分,毛红椿的生长均低于CK,其平均胸径、平均树高和单株材积分别较CK低5.9%、15.4%和24.8%;后期抑制层次的是MlT混交改造林分,造林后的前期(1~4 a)保持CK的正常生长速度,5~8 a生长最慢,混交效果极差。
The aim of this study was to investigate mixed transformation models of Toona ciliata and other broad-leaved tree species suitable for bare soil in mountainous areas within the southern forests.A newly established pure forest of T.ciliata(CK)was used as a control,while four types of mixed forest of Michelia odora×T.ciliata(MoT),Michelia macclurei×T.ciliata(MmT),Mytilaria laosensis×T.ciliata(MlT),and Sapindus saponaria×T.ciliata(SsT)were tested.We investigated forest structure,forest soil conditions,and the growth status of T.ciliata in all the forests from 1 to 8 years,and analyzed and compared the growth change in T.ciliata and its growth differences under the mixed transformation models.The results showed that all the forests developed complex structures after mixed transformation.The forest soil quality showed different levels of improvement,and the order of degrees of improvement was MoT>MmT>MlT>CK>SsT.The T.ciliata pure forest and the mixed transformation forests at different ages(4-8 years)showed different degrees of growth.The indexes of diameter at breast height(DBH)and stand height growth showed a"fast-slow"trend,and also showed the priority of their high growth rhythms.These characteristics of T.ciliata in mixed forests of MoT and MmT were particularly obvious.Toona ciliata is early shade-tolerant and affects the stand density of forest after reaching 4 years of age in the mixed transformation models,which have formed a more balanced pattern of space and time,and is suitable for the cultivation of large-diameter wood.Compared with pure T.ciliate forest,there were three levels(promotion characteristics,possible inhibition,and late inhibition)of the growth effect of mixed forests on T.ciliata,which were consistent with the forest age.Both the MoT and MmT transformation forests were highly effective in promoting the growth of T.ciliata.Compared with the pure T.ciliata forest,the average DBH,average stand height,and volume per plant of 8-year-old T.ciliata in MoT and MmT transformation forests increased by 19.8%,22.1%,and 71.8%and 25.7%,20.2%,and 85.1%,respectively.The SsT transformation forest appeared to inhibit the growth of T.ciliata,It was that T.ciliata occupied the main canopy in the SsT transformation forest,but it was lower than the growth performanceof pure forest of T.ciliata.The average DBH,average tree height,and individual average volume of T.ciliata in SsT transformation forest were as low as 5.9%,15.4%,and 24.8%,respectively.In MlT forest,at third level,T.ciliata maintained normal growth rate in the first 4 years after afforestation,but became the slowest of all models from 5 to 8 years,and the mixing effect was the lowest of all the forests.
作者
黄红兰
蔡军火
彭欢
张露
HUANG Honglan;CAI Junhuo;PENG Huan;ZHANG Lu(Jiangxi Environment Engineering Vocatinal College,Ganzhou,Jiangxi 341000,China;College of Forestry,Jiangxi Agricultural University,Nanchang,Jiangxi 330045,China;Collaborative Innovation Center of Jiangxi Typical Trees Cultivation and Utilization,Nanchang,Jiangxi 330045,China)
出处
《森林与环境学报》
CSCD
北大核心
2020年第5期497-504,共8页
Journal of Forest and Environment
基金
江西省科技支撑重点项目(20151BBF60019)
国家自然科学基金项目(31860202)。
关键词
毛红椿
混交改造
混交优化树种
生长效应
Toona ciliata var.pubescens
mixed transformation models
mixed optimization of tree species
growth effect
