高级检索+

缙云山常绿阔叶林栲种子产量及形态特征年际动态

Interannual dynamics of seed production and morphological traits of Castanopsis fargesii in evergreen broad-leaved forest of Jinyun Mountain

  • 摘要: 种子产量和种子形态特征是反映植物繁殖潜力及适应能力的2个重要生物学指标。从种群尺度和个体尺度分析缙云山常绿阔叶林优势种栲种子产量及其形态特征的年际差异及个体差异, 在此基础上进一步讨论栲的繁殖策略, 以期为植物结实动态的大尺度研究提供数据支持。研究基于2013—2021年缙云山常绿阔叶林永久样地内23株母树种子的连续监测数据。结果表明: 1)9年间共收集到栲成熟种子3万6 572颗, 种子产量为98.30颗/(m2·a); 种子产量的年际差异显著(P < 0.05), 其中2014、2018和2021年的产量明显大于其他年份; 不同母树个体的种子产量年际差异显著(P < 0.05), 且明显大于种群尺度下的年际差异。2)栲种子平均质量为(0.50±0.19)g, 平均变异系数为0.39, 年际间差异较大, 并与种子产量具有显著的负相关关系, 种子高宽比在年际间较为稳定, 且与种子产量没有明显的相关性, 平均变异系数为0.04。栲种子质量和高宽比的变异主要来自于个体间, 平均Gini系数分别为59.16%和69.77%。

     

    Abstract:
    Background Seed production and seed morphological traits are two important biological indicators of plant fruiting, reflecting the reproductive potential and adaptability of plants to the environment. The variation of seed production and morphological traits is common in woody plants and affects population dynamics, community species composition, and the maintenance of biodiversity. Thus, the interannual variation of seed production and seed morphological traits of Castanopsis fargesii were analyzed at population and individual levels. On this basis, the reproductive strategy of C. fargesii was discussed, so as to provide a data support for large-scale research on the dynamics of plant fruiting.
    Methods Taking the 23 individuals in 0.50 hm2 permanent monitoring plot of evergreen broad-leaved forest in Jinyun Mountain as the research object, we collected the seeds from 2013—2021. First the number of seeds were counted, then seed mass was weighted, seed height and width were measured after being air-dried. Seed production was defined as seed density, then the interannual coefficients of variation of seed production and morphological traits at population-level and individual-level were calculated, respectively. We used generalized linear mixed models to analyze the relationship between seed production and seed morphological traits.
    Results 1) Totally 36 572 mature seeds of C. fargesii were collected during 9 years, and the seed production was 98.30 seeds/(m2·a); The interannual variation of seed production was significant both at population-level and individual-level (P < 0.05), among which the production in 2014, 2018 and 2021 were significantly higher than those in other years. 2) The average seed mass was (0.50±0.19) g, and the average coefficient of variation was 0.39. The ratio of height to width was relatively stable between years, the average coefficient of variation was 0.04. The variation of seed mass and H/W ratio of C. fargesii mainly came from inter-individuals, with the average Gini coefficients were 59.16% and 69.77%, respectively.
    Conclusions 1) The seed production of C. fargesii showed clear masting signs, and the interval was about 3-4 years. The reproductive ability of different individuals in the population was quite different. 2) The intraspecific variation of seed mass and H/W ratio of C. fargesii was at a high level, which mainly from the inter-individuals. In addition, the seed mass also differed interannually, and it decreased with the increase of seed production, which suggested that mast-seeding may led to the reduction of seed mass. In contrast, the H/W ratio of seed was relatively stable between years, and had no significant correlation with seed production.

     

/

返回文章
返回