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为了解封育后桉树人工林的群落特征和演替趋势,以三峡库区中游地段世坪林场封育11年后的桉树人工林为研究对象,通过群落调查(样方法),分析了区系组成、群落外貌、垂直结构和主要种群年龄结构。结果显示,在4 800 m2样地中共记录维管植物(不含桉树)46科76属88种,科属分布型都以热带分布为主,但温带分布也占有一定比例;群落主要由具中小型革质全缘单叶的高位芽植物构成,但落叶树比例高于当地常绿阔叶林;群落层次分明,可分为乔木层、亚乔木层、灌木层、草本层;优势种巨桉(Eucalyptus grandis)更新不良,将会逐渐衰退,而杉木(Cun-ninghamia lanceolata)、丝栗栲(Castanopsis fargesii)和小红栲(C.carlesii)种群径级结构呈金字塔型,幼苗储备充足,为增长种群。通过分析桉树人工林的群落特征和主要种群年龄结构,认为封育后三峡库区桉树人工林处于向地带性常绿阔叶林演替过程中一个不稳定的过渡阶段,随着演替的进行,桉树的优势地位将逐渐为丝栗栲和小红栲等顶级树种所取代。
In order to understand the community characteristics and succession trend of the eucalyptus plantations after the enclosure, the eucalypt plantation 11 years after the resection of the plantation in the middle reaches of the Three Gorges Reservoir area was selected as the research object. Through the community survey (sample method) Composition, community appearance, vertical structure and age structure of main populations. The results showed that there were 88 species of 46 genera and 76 genera of vascular plants (excluding eucalyptus) in 4 800 m2 plots. The genera were mainly distributed in the tropical zone, but the temperate zone also occupied a certain proportion. The community consisted of 88 Small leathery single-leaf allotrophic plants, but the proportion of deciduous trees is higher than that of the local evergreen broad-leaved forest. The community is distinct and can be divided into arbor, sub-arbor layer, shrub layer and herb layer. Eucalyptus grandis) will gradually decline, while the diameter structure of Cun-ninghamia lanceolata, Castanopsis fargesii and C.carlesii is pyramidal, and the seedling reserves are sufficient to increase Population. By analyzing the community characteristics of Eucalyptus plantation and the age structure of the main population, it is considered that the Eucalyptus plantation in the Three Gorges reservoir area is in an unstable transitional stage to the succession of evergreen broadleaved forests. With the succession , The dominance of eucalyptus will gradually replace the top species such as red chestnut and red crested ibis.