秋茄新生小枝生长性状季节动态规律研究

Seasonal dynamics in growth traits of newly emerged twigs of Kandelia obovata

关键词:  生长性状, 主成分分析, 生长策略, 红树植物, 植物生态

Key words:  growth traits, principal component analysis(PCA), growth strategies, mangrove plants, plant ecology

摘要:

新生小枝是植物分支系统中最活跃的部分,对光照、温度等生境变化的响应最为敏感,分析植物新生小枝茎叶性状差异和评价其生长状况,对于理解植物的生长生存策略和适应性机制极为关键。秋茄作为常绿阔叶小乔木,其冠层在一年内不同季节都会产生一定数量的新生小枝。为深入了解秋茄新生小枝的生长状况和季节动态规律,探究以秋茄为代表的红树植物生长生存策略,该研究通过对秋茄新生小枝茎叶生长性状的调查和测定,结合方差分析、多重比较和主成分分析(PCA)等统计方法,综合评价不同季节秋茄新生小枝的生长表现。结果表明:(1)表征秋茄新生小枝生长状况的14个性状指标具有较大变异,变异系数范围为13.856%～56.469%,平均变异系数为35.627%,并且指标间具有较强的相关性。(2)秋茄新生小枝生长性状在不同季节存在显著性差异(P<0.05),总体表现为7月>5月>3月>10月。(3)秋茄新生小枝生长性状重要性排序为叶性状(55.050%)>生物量(35.480%)>茎构型(9.470%),叶密度、叶茎生物量比、叶数量、叶生物量、大叶面积、茎长和叶面积比7个性状指标总权重占比为87.146%,是表征秋茄新生小枝生长状况的关键指标。综上认为,秋茄新生小枝生长状况反映了树体对资源水平的适应策略,外因(光照和温度)及内因(生长策略)共同影响着新生小枝的生长状况。该研究结果揭示了秋茄新生小枝对不同生长季节环境变化的响应,为秋茄的种群保护和可持续发展提供了参考依据。

Abstract:

Newly emerged twigs are the most active part of plant branch systems and are most sensitive to changes in habitat such as light and temperature. Analyzing the differences in stem and leaf traits of new twigs and evaluating their growth status is crucial for understanding the growth and survival strategies of plants and their adaptability mechanisms. As an evergreen broad-leaved small tree, the crown of Kandelia obovata produces a certain number of new twigs in different seasons within a year. To gain a deeper understanding of the growth status and seasonal dynamics of new twigs of K. obovata, this study investigated the growth traits of the stems and leaves of new twigs. Statistical methods such as analysis of variance, multiple comparisons, and principal component analysis(PCA)were used to comprehensively evaluate the growth performance of the twigs in different seasons and to explore the growth and survival strategies of mangrove plants, represented by K. obovata. The results were as follows:(1)The 14 trait indicators characterizing the growth status of the twigs showed significant variation, with a coefficient of variation ranging from 13.856% to 56.469%, and a strong correlation between the indicators.(2)The growth traits of the twigs varied significantly in different seasons(P<0.05), with the overall performance being July>May>March>October. Additionally, the importance of the growth traits was ranked as leaf traits > biomass > stem configuration.(3)The importance of growth traits was ranked as leaf traits(55.050%)>biomass(35.480%)>stem configuration(9.470%). The total weight proportion of the seven trait indicators such as leaf density, leaf and stem biomass ratio, leaf number, leaf biomass, big leaf area, stem length, and leaf area ratio was 87.146%, which were the key indicators characterizing the growth status of the twigs of K. obovata. In conclusion, the growth status of the twigs reflects the adaptation strategy of the tree to resource levels, influenced by external factors such as light and temperature, as well as internal factors such as growth strategies. These research results provide insight into the response of the twigs to environmental changes in different seasons and offer a reference basis for the protection and sustainable development of K. obovata population.