The ability of community species to adapt to the environment and use resources and the importance of species in the ecological system in time and space are generally represented by ecological niche. In order to study the niche characteristics and dynamic changes of the dominant species in the arbor layer of the 4hm2Pinus tabuliformis-Quercus wutaishansea mixed forest sample plot in Lingkong Mountain,and to gain a better understanding of the competition and coexistence among species in the sample plot, this study was conducted based on a typical community investigation. Four indices of important value, niche width, niche overlap, and niche similarity were chosen to calculate and analyze the niche characteristics and examine dynamic changes over a period of 10 years from 2011 to 2021. The results showed that: (1) In 2021, the important values for Quercus wutaishansea and Pinus tabuliformis were 19.906 and 13.906, respectively.The niche widths were 0.962 and 0.555, which showed difference compared to those in 2011. Both were much larger than other species, indicating that they occupied an absolutely dominant position in the community. (2) The mean values of niche overlap and similarity of dominant species in the arbor layer of the Lingkong Mountain sample plot have both increased over the past 10 years. Additionally, the species pairs with the highest overlap and similarity values have changed, suggesting an intensification of competition among these species.

中文翻译：

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灵空山4hm2油松-五台山海栎混交林乔木层优势种生态位特征及动态

群落物种适应环境和利用资源的能力以及物种在生态系统中在时间和空间上的重要性一般用生态位来表征。为研究灵空山4hm2油松-五台山海栎混交林样地乔木层优势种的生态位特征和动态变化，更好地了解样地内物种间的竞争与共存情况，本研究是在典型的社区调查的基础上进行的。选择重要价值、生态位宽度、生态位重叠、生态位相似度四个指标，计算分析生态位特征，考察2011年至2021年10年间的动态变化。结果表明：（1）2021年，五台山栎和油松的重要值分别为19.906和13.906，生态位宽度分别为0.962和0.555，与2011年相比有差异，均远大于其他物种，表明它们在生态位中占据绝对优势地位。社区。 (2)灵空山样地乔木层生态位重叠度和优势种相似度平均值近10年均有所增加。此外，重叠度和相似度最高的物种对发生了变化，表明这些物种之间的竞争加剧。