Page 137 - 《广西植物》2025年第11期
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11 期 张晓荣等: 广西大瑶山常见孑遗裸子植物与阔叶树种枝叶性状的比较 2 0 8 1
( 1. Guangxi Key Laboratory of Forest Ecology and Conservationꎬ Guangxi Colleges and Universities Key Laboratory for Cultivation and
Utilization of Subtropical Forest Plantationꎬ College of Forestryꎬ Guangxi Universityꎬ Nanning 530004ꎬ Chinaꎻ 2. Guangxi
Paiyangshan Forest Centreꎬ Chongzuo 532500ꎬ Guangxiꎬ Chinaꎬ 3. Guangxi Dayaoshan Forest Ecosystem
Positioning Observation and Research Stationꎬ Laibin 546100ꎬ Guangxiꎬ China )
Abstract: A variety of relict gymnosperms are distributed in the evergreen broad ̄leaved forest in Dayao Mountainsꎬ
Guangxi. Understanding their environmental adaptations is essential for developing rational conservation strategies. To
compare and analyze the differences in stem and leaf traits between relict gymnosperms and the dominant broad ̄leaved
tree species coexisting with themꎬ this study selected four common relict gymnosperm species and six broad ̄leaved tree
species from the local evergreen broad ̄leaved forest. Considering the characteristics of the montane environmentꎬ this
study measured the leaf low temperature semi ̄lethal temperatureꎬ specific leaf areaꎬ sapwood ̄specific conductivityꎬ wood
densityꎬ saturated water content (of leaves and stems)ꎬ and bending strength. The results were as follows: (1) There
were significant inter ̄specific differences in the stem and leaf traits among the 10 woody plant species. The leaf low
temperature semi ̄lethal temperature ranged from -23.13 to -9.46 ℃ꎬ specific leaf area varied from 56.80 to 154.00
2  ̄1  ̄1
cm g ꎬ saturated water content ranged from 0.81 to 1.25 gg ꎬ sapwood ̄specific conductivity ranged from 0.74 to
 ̄1  ̄1  ̄1  ̄3
1.77 kgm MPa s ꎬ wood density was 0.48- 0.67 gcm ꎬ and bending strength was 61.55- 138.14 N
 ̄2
mm . (2) There were no significant differences in the means of all measured traits between relict gymnosperms and
broad ̄leaved tree species. (3) Except for the correlation between wood density and saturated water contentꎬ there were
no significant correlations between the other pairs of measured traits. These results indicate that relict gymnosperms and
angiosperms exhibit diverse combinations of stem and leaf traitsꎬ which is beneficial for their coexistence in the
subtropical montane evergreen broad ̄leaved forest. This study contributes to maintaining the integrity of mountain
ecosystems and provides a theoretical basis for the conservation of relict gymnosperms.
Key words: leaf low temperature semi ̄lethal temperatureꎬ water transport efficiencyꎬ bending strengthꎬ freeze injuryꎬ
water relationship
广西大瑶山是我国南岭山地生态功能区的重 植物生理生态学领域的重要问题( Meinzer et al.ꎬ
要组成部分ꎬ处于北热带-南亚热带气候过渡区ꎬ 2009ꎻ Franklin et al.ꎬ 2023)ꎮ 被子植物叶片因比
生物多样性丰富(Sun et al.ꎬ 2014ꎻ Lvꎬ 2023)ꎮ 山 叶面积大、木质部水分运输能力高而具备更高的
地常绿阔叶林主要分布在海拔 1 200 ~ 1 500 m 区 资源获取效率和生长能力ꎬ这种能力使其在资源
域ꎬ人为干扰较少ꎬ其中分布有多种孑遗裸子植 丰富的环境中占据优势( Carnicer et al.ꎬ 2013)ꎮ
物ꎬ 如 银 杉 ( Cathaya argyrophylla )、 长 苞 铁 杉 裸子植物木质部无导管组织ꎬ边材比导率低ꎬ但具
( Nothotsuga longibracteata )、 福 建 柏 ( Fokienia 有较强的胁迫抗性ꎬ主要分布在较为寒冷、干旱的
hodginsii) 及 罗 汉 松 ( Podocarpus macrophyllus) 等ꎮ 生境(Jin et al.ꎬ 2019ꎻ Liu et al.ꎬ 2024)ꎮ 在大瑶
这些孑遗植物是古老的“ 活化石”ꎬ其形态和生理 山的山地常绿阔叶林中ꎬ孑遗裸子植物与阔叶树
特征保留了中生代至新生代的演化痕迹ꎬ为研究 种共存在同一生境中ꎬ对比分析其功能性状有助
植物进化与环境适应提供了独特视角( Hampe & 于了解其生理生态适应策略的差异以及对环境变
Petitꎬ 2005ꎻ 商侃侃等ꎬ 2011ꎻ Cao et al.ꎬ 2020)ꎮ 化的响应ꎬ但相关研究尚未开展ꎮ 山地常绿阔叶
前期研究表明ꎬ孑遗植物对气候变化较为敏感( 谭 林植物在冬季易受冻害影响( 朱宏光等ꎬ2011ꎻ 周
雪等ꎬ2018)ꎬ加之自然干扰和人为活动等因素的 晓果等ꎬ2017)ꎮ 当植物处于低温环境时ꎬ不仅会
影响ꎬ其栖息地不断丧失ꎬ种群数量逐渐减少ꎬ已 造成植物组织结冰( 胞间和胞内结冰)ꎬ导致细胞
被列为国家重点保护珍稀植物( 邱迎君等ꎬ2011ꎻ 脱水和机械损伤ꎬ引起生理代谢失调ꎬ严重时还会
冉巧等ꎬ2019)ꎮ 因此ꎬ了解它们的环境适应策略 导致植物死亡( 王小菁ꎬ 2019)ꎮ 叶片低温半致死
对多样性保护和种质资源利用具有重要意义ꎮ 温度指叶片 PSⅡ最大光化学量子产量降低 50%时
被子植物和裸子植物功能性状的比较研究是 的温度ꎬ表征植物叶片在低温下的生理阈值ꎬ这一

