金华北山常绿阔叶林群落结构及优势乔木树种更新类型

Community structure and regeneration types of dominant species in an evergreen broad-leaved forest in Mount Beishan of Jinhua， China

关键词:  常绿阔叶林  群落结构  更新类型  演替

Key words:  evergreen broad leaved forest  community structure  regeneration type  succession

摘要:

以金华北山常绿阔叶林为对象，对群落的结构特征和优势乔木树种的更新进行调查研究。根据调查统计，群落共有维管植物66科115属144种，木本植物中的常绿阔叶树种以壳斗科、樟科、山茶科为主，达到62.96%，体现了亚热带常绿阔叶林的特点。该群落可划分为乔木层、灌木层、草本层和层间4个层次，其物种多样性表现出灌木层＞乔木层＞层间＞草本层的特点。根据径级频率分布形状，将各树种的种群结构归纳为4种类型，并结合各种群的生物学和生态学特性，分别讨论其更新类型，同时对群落所处的演替阶段进行诊断。结果为：（1）群落的建群种为木荷、苦槠，枫香、马尾松等也占有一定优势。（2）种群结构为逆-J字型的木荷、苦槠、香樟，耐荫性强，可以通过实生和萌生两种方式实现种群的更新，是顶极群落的优势种；L型的GFDA1木、女贞、格药柃等均为常绿阔叶小乔木或者大灌木，是顶极群落亚乔木层和灌木层的主要组成种；间歇型的枫香、麻栎、锥栗等，种群结构具有机会性和波动性，体现出顶级性先锋种的特性；纺锤型的白栎、马尾松和杉木为高大阳性树种，是演替序列中的先锋种，在此群落中种群更新不足，已表现出衰退的迹象。（3）该群落正处于顶级演替的前期，并未达到最终阶段，将进一步向以木荷、苦槠为优势种的方向发展。

Abstract:

This study was carried out in the evergreen broad leaved forest of Mount Beishan of Jinhua. The community structure and dominant species of the forest were analysed in this paper. The results showed that there were 100 species，67 genera and 31 families of vascular plants. The evergreen broad leaved trees in woody plants were mainly composed of Fagaceae，Theaceae and Lauraceae，which accounted for 62.96%. And the structure incarnated the characteristics of the evergreen broad leaved forest. The species diversity of four layers in the forest was analysed，and the result was shrub layer＞tree layer＞inter layer＞herb layer. The population structures of the different tree species were categorized into four regeneration types based on their size class frequency distribution patterns. After that，combining the biological with ecological characteristics of that species，the diagnosis of succession stage of this community was carried out. Important findings were obtained：(1)The constructive species of this community were Schima superba and Castanopsis sclerophylla，furthermore，Liquidambar formosana and Pinus massoniana also holded important dominance.(2)Inverse J type species，such as Schima superba，Castanopsis sclerophylla and Cinnamomum camphora，were strong shade tolerant and dominant species in climax forest，they could regenerate through seedling bank or sprouting under the closed forest canopy；L type species，such as Loropetalum chinensis，Ligustrum lucidum and Eurya muricata，were broad leaved evergreen small trees or large shrubs，and they were the main components of upper tree layer and shrub layer species in climax community；Sporadic(multimodal)type species，such as Liquidambar formosana，Quercus acutissima and Castanea henryi，had the opportunity and volatility to the population structure，reflecting the characteristics of top pioneer species；Spindle type species，such as Quercus fabri，Pinus massoniana and Cunninghamia lanceolata，were high positive and the pioneer species in the successional sequence，but they had showed a recessionary signs because of the lack of updated population in the community；(3)The successional stage of the forest was classified as a late seral stage community that would develop into a climax community dominated by Schima superba and Castanopsis sclerophylla.