南岳衡山马尾松天然林径级结构特征研究

Study on litter composition characteristics of Pinus massoniana natural forest in Hengshan,Nanyue

以南岳衡山马尾松天然林为研究对象,分析其径级分布特征。结果表明:衡山马尾松天然林已进入成熟林阶段,乔木层优势树种是马尾松,灌木层优势树种是檵木,侵入的阔叶树种较少。檵木的相对多度为82.27%,马尾松的相对显著度为86.68%。以2 cm为径阶步长,胸径大于1 cm林木的径级分布为单峰分布,其峰值在2~4 cm径阶;以4 cm为径阶步长,胸径大于5 cm林木的径级分布为“L”分布。檵木和其他树种均为单峰分布,峰值在2~4 cm径阶,而马尾松没有明显的峰形,各径阶内的林木分布较均匀。

In thispaper,the natural forest of Pinusmassoniana in Hengshan Mountain wastaken asthe research object,and the distribution characteristicsof diameter classwere analyzed.The resultsshowed that the natural forest of P.massoniana in Hengshan Mountain had entered the mature stage.The dominant tree speciesin tree layer wasP.massoniana,and in shrub layer wasLoropetalum chinense.In addition,there were few invasive broad-leaved species.The relative abundance of L.chinense was82.27%,and the relative dominance of P.massoniana was86.68%.The diameter distribution of treeswith DBH greater than 1 cm wasunimodal when 2 cm wastaken asthe diameter step size,and the peak value wasin the 2~4 cm diameter step,which wasdifferent from the"L"distribution of the treeswith the DBH greater than 5 cm with the diameter step size of 4 cm.Compared with tree species,L.chinense and other tree specieshad a single peak distribution with a peak value of 2~4 cm diameter steps,while P.massoniana had no obviouspeak shape.The distribution of each diameter step wasmore uniform.