辽东山区红松人工林不同林龄林下灌草多样性研究

Species Diversity of Shrub and Herb Layers in Pinus koraiensis Plantations with Different Forest Ages in Eastern Liaoning Mountain Region

采用空间代替时间的研究方法,选择辽东山区林龄分别为10年生、24年生、34年生、43年生、54年生红松人工林为研究对象,通过野外样地调查,记录并分析5种林分林下植被的组成、优势种和物种多样性的变化,探究不同林龄红松人工林林下灌草多样性特征。结果表明:红松人工林林下灌草组成丰富,随着林龄的增加,林下灌草分别有34、42、54、46、56种。从物种数量上看,随着红松人工林林龄的增加,灌草总数量和草本植物数量总体呈现上升的趋势,灌木数量则呈现先升高再降低的趋势。从重要值看,灌木层中,卫矛和辽东楤木是优势种;草本层中,白屈菜、透骨草和白花碎米荠等为优势种。从物种多样性看,灌木层中,物种丰富度指数呈现随着林龄的增加而波动上升的趋势,Simpson多样性指数和Shannon–Wiener多样性指数则随着林龄增加而先上升后降低,群落均匀度指数J_(D)和J_(H)在不同林龄间变化不大;在草本层,S、D、H、J_(D)和J_(H)等5个多样性指数总体上均表现出随着林龄的增加而持续上升的趋势。处于结果盛期的红松林林下灌草总数量、草本植物数量和草本多样性指数均较高。研究可为保护林下植物多样性,发挥灌草多样性的生态效益,维持和促进红松人工林生态系统的平衡与稳定提供参考。

In this study,using the method of replacing time with space,10 years old,24 years old,34 years old,43 years old and 54 years old Pinus koraiensis plantations were selected as the research objects.In order to explore the diversity characteristics of understory shrub and grass of P.koraiensis plantations of different ages in the mountainous area of eastern Liaoning Province,the changes of understory vegetation composition,dominan species and species diversity of 5 stands were recorded and analyzed through field plot investigation.The findings indicated that species composition of P.koraiensis plantation was abundant,and there are 34,42,54,46 and56 understory species at different increasing forest ages.From the perspective of species number,with the increase of stand age of P.koraiensis plantation,the total number of species and the number of herbaceous plan species showed an overall trend of increase,while the number of shrub plant species showed a trend of increase first and then decrease.From the perspective of important value,Euonymus alatus and Aralia elata var.glabrescens were used as dominant species in the shrub layer,Chelidonium majus,Phryma leptostachya subsp.asiatica and Cardamine leucantha are dominant species in the shrub layer.From the perspective of species diversity,in the shrub layer,S showed a fluctuating upward trend with the increase of stand age,and D and H showed a trend of increase first and then decrease,while J_(D)and J_(H)had little change between different forest ages.In the herb layer the 5 diversity indices of S,D,H,J_(D)and J_(H)generally showed a continuous upward trend with the increase of stand age.The total number of understory species,the number of herbaceous plants and the index of herbaceous diversity of P.koraiensis plantation in the peak fruiting period were high.The study provides a reference for improving the diversity of understory vegetation,playing ecological benefits,maintaining and promoting the balance and stability of P.koraiensis plantation ecosystem.