Abstract: To understand the crucial dependency factors of seedling abundance with a diameter at breast height (DBH) <1 cm in a mid-montane moist evergreen broad-leaved forest of 4 hm2 Gaoligong Mountains forest. The generalized linear mixed models were used to analyze whether neighbor density and habitat factors shaped seedling abundance at the community and species level, and whether the strength of them varied with temporal. The results showed that: (1) The effect of neighbor density and habitat factors on all seedling abundance were significant and gradually strengthen at the community level. The positive correlation of common species with heterospecific neighbor density increased significantly, while no correlation with environmental factors. The seedling abundance of rare species reflected non-significant with neighbor density and environmental factors. (2) At species level, the seedling abundance of Psychotria morindoides was only slightly and significantly negatively associated with elevation in 2022. From 2020 to 2023, the significant positive effects of biotic and habitat heterogeneity on seedling abundance of Myrsine semiserrata. The higher canopy openness, elevation, and soil total potassium and temperatures, the higher seedling abundance. However, these correlations were non-significant on the seedling abundance of Symplocos stellaris var. aenea in the four periods. This study indicated that the seedling abundance is driven by both neighbor density and habitat heterogeneity. The strength of neighbor densities and habitat factors differs greatly among community, species and temporals, which relative importance of variables can maintain the community diversity in the plot.

Key words: Gaoligong Mountains, neighbor density, habitat heterogeneity, seedling abundance, generalized linear mixed model

摘要： 为探究高黎贡山中山湿性常绿阔叶林4 hm2内胸径(DBH) <1 cm的幼苗多度的关键影响因素，利用广义线性混合模型在群落水平和物种水平分析邻体密度和生境因子是否影响幼苗多度，制约强度是否因时间而异。结果显示：(1) 群落水平上的总物种幼苗多度与邻体密度和生境因子的相关性随时间增加；常见种幼苗多度与异种大树邻体密度正相关呈显著增加趋势，与环境因子无相关性；稀有种幼苗多度与邻体密度和环境因子均无显著性。(2) 在物种水平上，聚果九节Psychotria morindoides幼苗多度仅在2022年与海拔和凸度分别呈边缘显著负相关和正相关；邻体效应和环境异种性对针齿铁仔Myrsine semiserrata幼苗多度在2020～2023年有显著正效应，表明存在正密度制约效应；在较高林冠开度、海拔和土壤含钾生境下，幼苗多度较高；而铜绿山矾Symplocos stellaris var. aenea幼苗多度在4个时段与邻体密度和环境因子均无显著相关性。研究表明，高黎贡山幼苗多度格局同时受到邻体密度和生境因子影响，这种影响强度在不同水平、物种和时空格局中差异显著，影响因素的相对重要性维持着该样地群落多样性。

关键词: 高黎贡山, 邻体密度, 生境异质性, 幼苗多度, 广义线性混合模型