Page 16 - 《广西植物》2023年第11期
P. 16

1 9 7 6                                广  西  植  物                                         43 卷
                 Abstract: Leaf and root are the most sensitive organs to environmentꎬ exploring the relationship between root and leaf
                 functional traits and their responses to environmental factors is helpful to reveal the utilization of resources by plants and
                 their adaption trategies to environment. In order to explore the adaptive strategies of coastal plantsꎬ the sandy coastal
                 herbaceous plants in Pingtan Island were taken as the research objects. Three distance gradients were set up from sea and
                 land. Six leaf function traitsꎬ leaf thicknessꎬ individual leaf areaꎬ leaf dry matter contentꎬ specific leaf areaꎬ leaf tissue
                 densityꎬ leaf phosphorus contentꎬ and five fine root function traitsꎬ root average diameterꎬ root tissue densityꎬ specific
                 root lengthꎬ specific root areaꎬ root phosphorus contentꎬ were measured to analyze the function traits of leaf and root of
                 coastal plants and their responses to soil factors. The results were as follows: (1) The variation coefficient amplitude of
                 root and leaf function traits in intertidal zone was the smallestꎬ and it was the largest on the gradient 30-60 m away from
                 the high tide line. The individual leaf areaꎬ leaf phosphorus contentꎬ root average diameterꎬ root tissue densityꎬ and root
                 phosphorus content increased with the distance from sea to landꎻ the leaf dry matter contentꎬ leaf tissue densityꎬ specific
                 root length and specific root area decreased. (2) Plants balanced resource allocation between growth and defense through
                 trait combinationsꎬ which showed that there were different degrees of correlation among leaf traitsꎬ root traits and root ̄
                 leaf traits. Among the aboveground and underground corresponding traitsꎬ leaf thickness ̄root average diameterꎬ leaf ̄root
                 phosphorus content were significantly positively correlated. Specific leaf area with specific root lengthꎬ specific root areaꎬ
                 leaf tissue density ̄root tissue density had no significant correlation. (3) The interpretation degree of soil factors to the
                 changes of coastal plant functional properties was 52.05%ꎬ of which the soil salt content had the greatest impactꎬ
                 followed by soil water contentꎬ soil electrical conductivity and soil pH value. In conclusionꎬ in the harsh coastal
                 environmentꎬ the soil salt contentꎬ soil electrical conductivityꎬ soil water content and soil pH value decrease gradually
                 from sea to landꎬ and the overall environment is low in phosphorus and high in salinity. The plants have shown different
                 survival strategies: the plants closer to the sea adopted the strategy of leaf resource conservation type and root resource
                 acquisition typeꎻ the plants farther away from the seaꎬ the strategy of leaf resource acquisition type and root resource
                 conservation type is adopted. The results of this study provide a certain reference value for understanding the response
                 mechanism and adaptability of coastal herbs to environmental gradient changesꎬ which is conducive to the analysis of soil
                 and other environmental characteristics to screen and plant suitable species according to gradientꎬ and promote the
                 restoration and protection of coastal plants.
                 Key words: coastal plantsꎬ leafꎬ fine rootꎬ functional traitsꎬ soil factorsꎬ ecological strategy



                对于脆弱的海岛生态系统来说ꎬ海岸起到生                            比叶面积和叶面积以提高对光资源的捕获及利用
            态屏障的作用ꎬ海岸植被处于海陆过渡区ꎬ对海潮                             效率(李磊等ꎬ2022)ꎻ乔木如木麻黄、湿地松等则
            冲刷、风沙 入 侵 等 具 一 定 缓 冲 作 用 ( 王 贵 霞 等ꎬ               减小比叶面积和叶面积、增加叶厚和叶干物质含
            2005)ꎬ具有重要的生态价值ꎮ 但是ꎬ海岸前沿沙                          量以维持高养分重吸收效率( 周丽丽等ꎬ2019) 等
            地长期受到海风、浪潮、强光高温以及人为干扰的                             方面的研究ꎮ 虽然有一些关于根系结构、形态及
            影响ꎬ适生植物少ꎬ植物群落物种类型趋于单一                              分布特征等研究ꎬ但是多集中在单一器官的功能
            (吴雅华等ꎬ2021)ꎬ极具脆弱性ꎬ一旦被破坏或演                          性状ꎮ 例如ꎬ孙佳等(2021) 探讨滨海滩涂不同种
            替退化便很难自行恢复ꎮ 植物在生长过程中会响                             群密度对植物根系形态及生长特征的影响ꎻ李永
            应各种环境因子变化而采取合适的生存策略ꎬ具                              涛等(2020)研究分析海岸盐碱地不同林龄植物根

            体会体现在功能性状上的变化( 赵广帅等ꎬ2020)ꎮ                         系分布与土壤的交互影响等ꎮ
            目前ꎬ关于植物功能性状及其与环境的关系的研                                  叶是植株地上部分对环境变化最灵敏且可塑

            究较多集中在内陆森林和草地( 张景慧等ꎬ2021ꎻ                          性最大的器官ꎬ其性状特征对光合、呼吸、蒸腾等
            吴旭东等ꎬ2021ꎻ孙鹏等ꎬ2022)ꎬ而针对海岸植物                        生理过程有直接影响( 张林和罗天祥ꎬ2004ꎻ毛伟
            的研究相对较少ꎬ并且大部分集中在叶功能性状                              等ꎬ2012)ꎮ 根系作为植物地下部分与土壤因子相
            研究(刘 远 瞻 等ꎬ2020ꎻ张 秀 芳 等ꎬ2020ꎻ王 旭 等ꎬ                互作用的重要器官( 徐冰等ꎬ2010)ꎬ细根( 一般直
            2022ꎻ何雅琴等ꎬ2022)ꎮ 例如ꎬ滨海竹类通过增加                       径<2 mm) 对土壤环境变化十分敏感( Mccormack
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