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草本层是森林生态系统的重要组成部分,对维持森林生物多样性具有重要意义。本文以长白山阔叶红松(Pinus koraiensis)林25 ha固定监测样地为研究平台,运用不同的统计模型(对数正态模型和对数级数模型)及机理模型(包括生态位模型:断棍模型和生态位优先占领模型;中性模型:复合群落零和多项式模型和Volkov模型),对不同季节草本物种多度分布进行拟合。采用Kolmogorov-Smirnov和AIC检验确定最优模型,以揭示草本层物种多度分布格局随季节的变化规律,探讨草本层物种组成与结构背后的生态学过程。结果表明:(1)草本层物种多度分布季节差异明显。春季各多度级物种数差异不大,夏季中间种较多,秋季则是稀有种较多;(2)模型拟合结果显示,不同季节草本层物种多度分布的最优拟合模型相近。统计模型中对数级数模型表现最优,机理模型中中性模型的拟合效果优于生态位模型。复合群落零和多项式模型较好地拟合了春夏季草本物种多度分布,Volkov模型较好地拟合了秋季草本物种多度分布。综上所述,尽管长白山阔叶红松林草本植物不同季节的物种多度分布格局不尽一致,但其背后的构建机制相似,中性随机过程在草本层物种多样性维持过程中显得更为重要。
Herbaceous layer is an important part of forest ecosystem and has great significance for maintaining forest biological diversity. In this paper, 25-ha fixed monitoring plots of Pinus koraiensis forest in Changbai Mountains were used as the research platform. Different statistical models (logarithmic normal model and logarithmic series model) and mechanism models (including niche model: And niche predominance model; Neutral model: zero-sum polynomial model of composite community and Volkov model) were used to fit the distribution of plant species abundance in different seasons. The Kolmogorov-Smirnov and AIC tests were used to determine the optimal model to reveal the distribution pattern of herb species with seasonal changes and to explore the ecological process behind the composition and structure of herbaceous species. The results showed that: (1) Seasonal distribution of herbivore species abundance was obvious. There was no significant difference in the number of species at spring level between species abundance in summer, more interspecies in summer and rare species in autumn. (2) The results of model fitting showed that the best fitting models of abundance distribution of herbaceous species in different seasons were similar. The logarithmic model in the statistical model performs best, and the fitting effect of the neutral model in the mechanism model is better than that in the niche model. The zero and polynomial models of composite communities fit well the spring and summer herbivores abundance distribution, and the Volkov model better fitted the abundance distribution of autumn herbaceous species. In summary, although the pattern of species abundance distribution differs in different seasons in broad-leaved Korean pine forests in Changbai Mountains, the construction mechanism behind them is similar. Neutral stochastic processes are more important in the maintenance of species diversity in herbaceous plants .