漓江流域常见植物叶片非结构性碳水化合物动态及其生态适应性

Dynamics and Ecological Adaptability of Non-structural Carbohydrates in Common Plant Leaves of the Lijiang River Basin

关键词:  非结构性碳水化合物（NSC）  淀粉  可溶性糖  不同降水季节  生态适应性

Key words:  Non-Structural Carbohydrates (NSC)  starch  soluble sugars  different precipitation seasons  ecological adaptability

摘要:

非结构性碳水化合物(Non-StructuralCarbohydrates,NSC)能够有效揭示植物对外界环境的适应性机制。为探究漓江流域植物在喀斯特与非喀斯特生境中不同降水季节的适应性变化,通过分析木本植物叶片中 NSC及其主要组分含量的动态变化与差异,旨在为不同生境下的适生植物筛选提供科学依据。在旱季与雨季分别采集12种代表性木本植物的叶片,测定其 NSC、可溶性糖和淀粉的含量。建立贝叶斯多元回归模型,定量分析不同降水季节、生境条件、植物生活型及生长型等因素对植物叶片 NSC及其主要组分含量的影响。结果表明:(1)12种植物叶片中,NSC旱季和雨季的平均含量为(114.80±62.84)mg/g,其组成以可溶性糖为主,旱季和雨季的平均含量为(84.23±57.04)mg/g,显著高于淀粉(30.60±23.06)mg/g。(2)不同降水季节之间,12种植物叶片的可溶性糖、淀粉含量存在显著的动态转换关系,雨季淀粉含量显著高于旱季,可溶性糖含量显著低于旱季。(3)喀斯特山坡与非喀斯特山坡生境植物叶片的淀粉、可溶性糖含量有显著性差异,而喀斯特洼地、垭口与非喀斯特生境植物叶片的 NSC及其主要组分含量无显著差异。(4)不同生活型植物叶片的 NSC及其主要组分含量差异显著,其中落叶植物叶片的 NSC及其主要组分含量均显著高于常绿植物;不同生长型间,乔木植物叶片淀粉含量显著高于灌木,而可溶性糖含量显著低于灌木。漓江流域常见植物叶片的 NSC、可溶性糖和淀粉含量与自身生物学特性、生境条件密切相关,同时还受到不同降水季节的影响,叶片 NSC含量的季节变化是一个较为复杂的动态过程。

Abstract:

Non-structural carbohydrates (NSC) can effectively reveal the adaptive mechanisms of plants to external environments. To explore the adaptive changes of plants in the Lijiang River Basin across karst and non-karst habitats during different precipitation seasons, we analyzed the dynamic changes and differences in the content of NSC and its components (soluble sugars and starch) in leaves, aiming to provide a scientific basis for the selection of suitable plants in different habitats. Leaves of 12 representative plant species were collected during both the dry and rainy seasons to measure the content of NSC, soluble sugars, and starch. A Bayesian multivariate regression model was established to quantitatively analyze the effects of different precipitation seasons, habitat conditions, plant life forms, growth forms, and other factors on the content of NSC and its components in plant leaves. The results showed that: (1) Among the 12 plant species, soluble sugars were the main component of leaf NSCs, with a total content of 84.23 ± 57.04 mg/g, significantly higher than the starch content of 30.60 ± 23.06 mg/g, while the total NSC content was 114.80 ± 62.84 mg/g. (2) Significant dynamic shifts were observed in the content of soluble sugars and starch in the leaves of the 12 plant species between different precipitation seasons, with starch content being significantly higher and soluble sugars content significantly lower during the rainy season compared to the dry season. (3) There were significant differences in the content of starch and soluble sugars in plants between karst slope and non-karst slope habitats, while no significant differences were found in the content of NSC and its components in the leaves of plants growing in karst depressions, passes, and non-karst habitats. (4) Significant differences in leaf NSC content was observed among plant life forms, with deciduous plants showing significantly higher NSC and component contents than evergreen plants; additionally, among different growth forms, tree species had significantly higher leaf starch content but significantly lower soluble sugars content compared to shrubs. The content of NSC, soluble sugars, and starch in the leaves of common plant species in the Lijiang River Basin is closely related to their biological characteristics and habitat conditions, and is also influenced by changes in different precipitation seasons. The seasonal variation in leaf NSC content is a relatively complex dynamic process.