西双版纳次生山乌柏林的群落学特征分析

ANALYSIS ON COENOLOGICAL CHARACTERISTICS OF Sapium discolor SECONDARY FORESTS IN XISHUANGBANNA

对西双版纳热带雨林经刀耕火种撩荒后形成的次生山乌桕林进行测定和研究。结果表明,在250cm^2的固定样地上,有维管束植物79种,隶属42科71属。由于受人为干扰较少,群落的层次分化比较明显,在结构上可分为乔木层(Ⅰ,Ⅱ),灌木层、草本层及层间植物,按(?)aunkiae生活型谱统计,以中高位芽植物占绝对优势,地面芽和地下芽植物很少。与该地区的季节性雨林相一致。对这些次生林采取封山育林措施。群落的恢复和发展较快,并将按着原生植被类型方向发展。封山育林是使这些次生植被尽快恢复成林的有效方法。

The paper presents the results of a 10—year study on the secondary forest vegetation which was naturally regenerated from slash and burn cultivation in the tropical rain forest. A fixed sample plot survey was excuted in Menglun, Mengla County, Xishuangbanna. A total of 79 species of higher plants in 42 families and 71 genera was observed in the 2500 m^2 fixed sample plot. The secondary forest is so less disturbed that stratification can be clearly divided into: arborous layer, shrub layer, herbaceous layer and lianas. In the arborous layer, the dominant tree is Sapium discolor, the important value of which is 36.12. The life form was measured according to Raunkiaer's system of classification, phanerophytes(89.88%), chamaeph ytes(3.85%) hemicryptophytes, (1.28%), geophytes(1.28%),and tberophytes (2.56%), epiphytes(1.28): the percentage of them is similar to the seasonal rain forest in Xishuangbanna. Studying on the secondary succession of tropical rain forest is to know the dynamics and regulation of secondary succession. It has important ecological significance for the recovery and development of forest ecosystem. 'Closing off the hills for natural regeneration' is an effective measure to rehabilitate the secondary forest vegetation.