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 Carbohydrate in Common Plant Leaves of the Lijiang River Basin

关键词:  非结构性碳水化合物  淀粉  可溶性糖  旱雨季；生态适应性

Key words:  non-structural carbohydrate  starch  soluble sugar  dry and rainy season  ecological adaptability

摘要:

非结构性碳水化合物（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季节的适应性变化，通过分析叶片中NSC及其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种代表性植物的叶片，测定其叶片NSC、淀粉、可溶性糖等含量。建立贝叶斯回归模型，定量分析不同季节、生境条件、植物生活型及生长型等因素对叶片NSC及其组分含量的影响。结果表明：（1）在12种植物中，叶片NSC的组成以可溶性糖为主，其总体含量为84.23±57.04 mg /g，显著高于淀粉含量30.60±23.06 mg /g，而NSC的总体含量为114.80±62.84 mg /g；（2）在旱季与雨季之间，12种植物叶片中的可溶性糖与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）喀斯特生境洼地、垭口生长的植物与非喀斯特生境的植物叶片NSC含量无显著差异，而喀斯特山坡与非喀斯特山坡生境间植物的淀粉、可溶性糖含量有显著性差异；（4）不同生活型的植物叶片 NSC差异显著，其中落叶植物NSC及其组分含量均显著高于常绿植物；同时，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中NSC、可溶性糖和淀粉含量含量与自身生物学特性、生境条件密切相关，还受到雨季和旱季变化影响，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 the external environment. In order to investigate the adaptive changes of plants in the Li River basin in different seasons in karstic and non-karstic habitats, we analyzed the dynamic changes and differences in the contents of NSC and its components in leaves, aiming to provide a scientific basis for the selection of suitable plants in different habitats. The leaves of 12 representative plants were collected in the dry and rainy seasons, and the contents of NSC, starch and soluble sugar were determined. A Bayesian regression model was established to quantitatively analyze the effects of different seasons, habitat conditions, plant life type and growth type on the contents of leaf NSC and its components. The results showed that (1) among the 12 plant species, the composition of leaf NSC was dominated by soluble sugars, with an overall content of 84.23±57.04 mg /g, which was significantly higher than that of starch, which was 30.60±23.06 mg /g, and the overall content of NSC, which was 114.80±62.84 mg /g. (2) Between the dry season and the rainy season, there was a significant difference in the soluble sugar and starch content had a significant dynamic conversion relationship; (3) there was no significant difference in the NSC content of the leaves of plants growing in the depressions and passes of karst habitats and those in non-karst habitats, whereas there was a significant difference in the starch and soluble sugar content of the plants between the karst hill slopes and the habitats of the non-karst hill slopes; (4) there were significant differences in the NSC content of the leaves of the plants with different life types, among which the content of the NSC and its components of the deciduous plants were all were significantly higher than those of evergreen plants; at the same time, the starch content of leaves of tree plants was significantly higher than that of shrubs, while the soluble sugar content was significantly lower than that of shrubs in different growth types. The contents of NSC, soluble sugars and starch in the leaves of common plants in the Li River basin are closely related to their own biological characteristics and habitat conditions, and are also affected by changes in the rainy and dry seasons, the seasonal change of leaf NSC content is a more complex dynamic process.