闽江江心洲不同生境植物叶功能性状差异及其对土壤特性的响应

Differences of plant leaf functional traits in different habitats and their responses to soil characteristics in central bar of Minjiang River

基于植物群落叶功能性状的角度研究植物群落与环境的关系有助于探究植物的适生策略。然而,目前关于江心洲植物群落叶功能性状的研究还有待深入探究。基于此,选取8项植物群落叶功能性状指标和9项土壤理化性质指标,探究闽江福州河段5个江心洲3种不同生境类型(洲岸沙滩、洲岸泥滩和洲中央林地)的植物群落叶功能性状与土壤因子特征及其响应机制。结果表明:(1)除土壤温度外,江心洲不同生境的其余8个土壤理化因子存在显著差异。(2)江心洲不同生境的植物群落叶功能性状存在显著差异。在灌木层上,洲中央林地的叶面积(80.935 cm^(2))显著高于洲岸泥滩(31.685 cm^(2))和洲岸沙滩(14.280 cm^(2));在草本层上,洲中央林地的比叶面积(535.684 cm^(2)/g)显著高于洲岸沙滩(384.974 cm^(2)/g);然而,在乔木层上,不同生境的植物群落叶功能性状无显著性差异。(3)影响江心洲不同生境植物群落叶功能性状的主要土壤因子不尽相同,洲岸沙滩为土壤温度,洲岸泥滩为土壤含水量、土壤全碳含量和土壤容重,洲中央林地为土壤容重和土壤含水量。研究发现,与相对远离闽江的洲中央林地相比,河流水动力和潮汐的干扰导致洲岸沙滩和洲岸泥滩的生境发生变化,植物群落通过调整资源分配利用的适生策略,权衡功能性状组合以适应环境的变化。

Studying the relationship between plant communities and the environment from the perspective of leaf functional traits of plant communities can help explore the adaptive strategies of plants.However,there is still a need for in⁃depth research of leaf functional traits of plant communities in central bar.Therefore,this study selected 8 indicators of leaf functional traits of plant communities and 9 indicators of soil physicochemical properties.In order to explore the characteristics of leaf functional traits of plant communities and soil indicators,and their response mechanisms in 3 different habitat types(sandy beach of bank,mudflat of bank and forest land of central bar)of 5 central bars in the Fuzhou Reach of Minjiang River.Except for soil temperature,the other eight soil physical and chemical factors showed significant differences among different habitats on the central bar.There were significant differences in leaf functional traits among plant communities in different habitats on the central bar.In the shrub layer,the leaf area of the central forest(80.935 cm^(2))was significantly higher than that of the mudflat of bank(31.685 cm^(2))and sandy beach of bank(14.280 cm^(2)).In the herb layer,the specific leaf area of forest land of central bar(535.684 cm^(2)/g)was significantly higher than that of sandy beach of bank(384.974 cm^(2)/g).However,in the arbor layer,there was no significant difference in leaf functional traits among plant communities in different habitats.The main soil factors affecting leaf functional traits of plant communities in different habitats of central bar were not entirely same.Soil temperature was the main factor in sandy beach of bank,while soil water content,soil total carbon content,and soil bulk density were the main factors in mudflat of bank,and soil bulk density and soil water content were the main factors in forest land of central bar.The research found that compared with the forest land of central bar which was relatively far from the Minjiang River,the disturbance of river hydrodynamics and tides led to changes in the habitat of sandy beach of bank and mudflat of bank.Therefore,plant communities adjusted their adaptation strategies for resource allocation and utilization,balancing functional trait combinations to adapt to environmental changes.