牯牛降自然保护区优势树种生长分析

Growth analysis on dominant tree species in Guniujiang nature reserve

【目的】研究牯牛降自然保护区优势树种的生态特征与生长动态,为探究马尾松—杉木优势树种的生态特征林分管理方法提供参考依据。【方法】在设立固定样地的基础上,调查并分析了优势树种马尾松、杉木的径级结构、胸径生长、年轮、树高和胸径关系。【结果】调查样地内的马尾松为第一优势种,但幼树较稀少,林冠下实生与萌芽大量分布的杉木为亚优势种;树木年轮显示出两优势树种的树龄相近,但马尾松的胸径生长量大于杉木,树高生长量也比杉木大。【结论】成熟林林冠层马尾松在牯牛降自然保护区的优势地位会降低,而杉木的优势地位会逐渐扩大。

【Objective】The study researched the ecological characteristics and growth dynamics of dominant tree species in Guniujiang nature reserve in order to provide reference for the ecological characteristics research and dominant tree species management methods for P. massoniana and C. lanceolata tree species. 【Method】Based on the establishment of permanent plots， the relationships between diameter class structure， DBH， tree height， and diameter growth rings of dominant tree species P. massoniana and C. lanceolata were investigated and analyzed. 【Result】Results showed that P. massoniana dominated the canopy layer， but P. massoniana sapling was rare， overall distribution C. lanceolata was considered to be the subdominant tree species in the forest distribution scale. Tree rings showed that the age of two dominant species were similar， but the DBH growth increment in P. massoniana was greater than that in C. lanceolata； also， the tree height growth of P. massoniana was greater than that of C. lanceolata. 【Conclusion】In the current mature forest canopy occupancy， the dominance of P. massoniana will be reduced while the dominance of C. lanceolata will gradually increase.