The present study was conducted in the secondary su btrop ical evergreen broad-leaved forests at altitude 1650～1670m in Mt.Wawusha n National Forest Park,southwestern China.In order to understand stand restoratio n dynamics,the stand structure in three permanent 0.04hm2 plots for 3～4t imes were recorded from 1982 to 1997 and expounded the changes in 15 years about tree composition,important value index,several diversity indices,structure and volume productivity of both communities and populations.The results were followe d：11 tree species disappeared and about another 10 species entered into tree lay er in the stand,keeping tree layer dynamic equilibrium and developing tree speci es diversity.The dominant species,Castanopsis platyacantha,assumed the super ior status,but its important value(Ⅳ)was decreased.The position of secondary do minant species,Schima sinense and Lithocarpus hancei, are gradually enha nced with gradually increased Ⅳ.The changes of densities,DBH and height dis tribution of tree populations displayed that the secondary evergreen forest was developed from past single or double dominant tree species to double or three do minant trees,from single tree layer to multiple levels in vertical structure.And the resulting community becomes more complicated and more stable.The growth rat es of average height and DBH of all main trees were 24～48cm.a-1 an d 0 .34～1.10cm.a-1,respectively.According to the differentiation of grow th,the main trees could be divided into three growth groups of species：fast-gro wing group including species of Schima sinense and Acanthopanax evodiaefoliu s var.gracills,slow-growing group of Machilus pingii and Lithocarpu s hancei, and the group in between of Castanopsis platyacantha and Cycl ob alanopsis myrsinaefolia. Volume productivity of the dominant population increa s ed firstly and then decreased,but the secondary tree population increased quickl y all the time.Volume productivity of all tree population in 1997 was up to betw een 218m3.hm-2 and 235m3.hm-2,and the change of dominant p opulation was a key for community productivity.The relations of DBH,height g rowt h and volume productivity in various density of the main tree populations indica ted that the densities was one of the most important factors influencing product ivity of tree populations under common environment with the interactions among t ree populations.It is suggested that there is no contradiction between tree spec ies diversity conservation and high volume productivity in forest restoration pr ocess.%在瓦屋山定位研究了中亚热带湿性常绿阔叶林次生 群落15a来各乔木种群组成及其重要值、密度、大小结构、高度结构和材积生产力等的动 态变化。结果表明：自然恢复过程中次生常绿阔叶林群落乔木层物种组成变化明显，有11种 从群落乔木层消失，也有10种出现，乔木层树种多样性(丰富度)基本保持动态平衡和发展； 优势种地位保持不变，但次优势种地位得以加强；群落结构变化较大，突出表现为种群密度 、胸径和树高分布格局的变化和立体空间的分化，群落由单优或双优种向双优或多优势种发 展，由单一乔木层向多层次立体结构发展，空间加厚，群落更复杂、稳定性增强。乔木种群 平均高生长速度在24～48cm.a-1，平均DBH生长率在0.34～1.10cm.a -1，各种群生长速度差异明显，按生长速度可划分为适应性强的速生树种如细梗吴茱萸 叶五加，华木荷(平均DBH生长在0.70cm.a-1以上)，中等速度的小叶青冈、 扁刺栲(平均DBH生长在0.40cm.a-1以上)，慢生种如润楠，石栎(平均DBH 生长在0.4cm.a-1以下)；种群材积生产力高低不一，优势种扁刺栲种群材积生 产力并不是一直增长，而是在后期出现下降；次优势种增长速度较快。1997年3固定样地材 积量218～235m3.hm-2，优势种群材积生产力是群落材积生产力高低的关键。在 相同的环境条件下和各种群相互作用下，密度是各种群生长和材积生产力高低的决定因 素之一。
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