干热河谷石漠化区顶坛花椒叶片功能性状的海拔分异规律

Leaf functional traits of Zanthoxylum planispinum var. dintanensis at different altitudes in dry-hot valley rocky desertification region

关键词:  干热河谷, 石漠化, 顶坛花椒人工林, 叶片功能性状, 海拔分异

Key words:  dry-hot valley, rocky desertification, Zanthoxylum planispinum var. dintanensis plantation, leaf functional traits, altitude differentiation

摘要:

为阐明顶坛花椒人工林叶片功能性状的海拔分异规律,探讨顶坛花椒对不同海拔生境的适应策略,该研究测定了叶片厚度、比叶面积、叶全氮含量等9个功能性状和土壤有机碳、全氮、全磷等8个环境因子,揭示了顶坛花椒人工林叶片功能性状的内在关联及其随海拔的分异规律。结果表明:(1)随海拔升高,顶坛花椒比叶面积、叶全磷、叶全钾含量先升高后降低,叶干物质含量、叶全氮含量先降低后逐渐升高,叶片厚度、叶面积及叶片含水率逐渐增大。(2)顶坛花椒叶片功能性状间具有显著的相关性,叶全氮与叶全磷呈显著负相关,与叶片厚度的关系则相反; 叶干物质含量与比叶面积、叶片含水率呈显著的抑制效应。(3)土壤因子对顶坛花椒叶片的影响表现为速效氮>速效钾>有机碳,其他土壤因子的影响较小。研究显示顶坛花椒主要通过增强防御功能性状、协调叶片养分含量的生存策略来提高获取资源和抵御外界环境胁迫的能力,对土壤养分具有强烈的依赖性,其干旱适应属性为干旱避免,该研究为顶坛花椒人工林复壮、高产与稳定,及喀斯特石漠化区生态修复提供科学依据。

Abstract:

In order to expound the law of altitude differentiation of leaf traits of Zanthoxylum planispinum var. dintanensis plantation, to explore the adaptation strategies in different altitude habitats. This study measured nine leaf traits such as leaf thickness, specific leaf area and leaf total nitrogen, and eight soil chemical indexes such as organic carbon, total nitrogen and total potassium that aim to analyze the correlation of leaf functional traits of Z. planispinum var. dintanensis and its differentiation with altitude. The results were as follows:(1)With the increase of altitude, the specific leaf area, leaf total phosphorus and leaf total potassium of Z. planispinum var. dintanensis increased first and then decreased while leaf dry matter content, leaf total nitrogen and leaf organic carbon decreased first and then increased gradually; and leaf thickness, leaf area and leaf water content increased gradually.(2)There was a significant correlation between the leaf functional traits of Z. planispinum var. dintanensis. Leaf total nitrogen had a significantly negative with total phosphorus in leaves, significant positively with leaf thickness. Leaf dry matter content has a significant inhibitory effect on specific leaf area and leaf water content.(3)The effect of soil factors on the leaves of Z. planispinum var. dintanensis was available nitrogen > available potassium > organic carbon, while other soil factors had less effect on it. This study indicates that Z. planispinum var. dintanensis mainly enhances the ability to acquire resources and resist external environmental stress by enhancing defense function traits and coordinating leaf nutrient content survival strategies. It has a strong dependence on soil nutrients, and its drought adaptation is drought avoidance. This study provides a scientific basis for the rejuvenation, high yield and stability of Z. planispinum var. dintanensis plantation and ecological restoration in karst rocky desertification area.