鲁西8种观赏竹细根功能性状与根际土壤养分的关系

Relationship between Functional Traits of Fine Roots and Rhizosphere Soil Nutrients of 8 Ornamental Bamboos in Western Shandong Province

为揭示北方城市观赏竹细根功能性状与根际土壤的互作机制,对不同竹种地下生态适应策略进行研究。以山东省聊城市百竹园8种观赏竹为研究对象,从土壤表层开始每10 cm分层获取根系和根际土壤样品,测定土壤理化性质和细根形态参数。结果表明:(1)不同竹种根际土壤养分含量存在较大差异,且随土壤深度的增加而递减,0~10 cm土层,斑竹、淡竹土壤有机质、全氮、有效磷、速效钾含量较高,金镶玉竹、蓉城竹、四季竹土壤养分较低。(2)不同竹种细根形态参数之间相关性显著,具有明显的垂直分布规律,细根生物量与细根总根长、表面积、体积、根长密度为极显著正相关,根组织密度与比根长、比根面积、根长密度为极显著负相关,斑竹、淡竹细根生物量和根组织密度较高,蓉城竹和四季竹有较高的比根长、比根面积。(3)细根总根长、表面积、体积、根长密度、细根生物量与土壤有机质和全氮呈显著正相关,土壤速效钾对细根形态的变异贡献率最高(34.2%)。斑竹、淡竹有良好的环境适应性,可以有效应用于北方城市绿化,合理增加表层土壤的肥力有利于促进细根的生长。

Underground ecological adaptation strategies of different bamboo species were investigated in order to reveal the relationship between functional traits of fine roots and rhizosphere soil of ornamental bamboo species in urban areas of northern China.Taking 8 ornamental bamboo species in Liaocheng Bamboo Garden of Shandong Province as research subjects,samples of root system and rhizosphere soil were obtained in consecutive soil layers of 10 cm in depth below the soil surface.The soil physical and chemical properties and the morphological parameters of fine roots were determined.The results showed that(1)The soil nutrient content of different bamboo species varied greatly and decreased with the increase of soil depth.The contents of organic matter,total N,available P and available K in the 0~10 cm soil layer of Phyllostachys bambusoides and Phyllostachys glauca were higher,but those of Phyllostachys aureosulcata McClure‘Spectabilis’,Phyllostachys bissetii and Oligostachyum lubricum were lower.(2)The correlation between fine root morphological parameters of different bamboo species was significant,with clear vertical distribution pattern.Fine root biomass was significantly and positively correlated with total root length,root surface area,root volume,and fine root length density.Root tissue density was significantly and negatively correlated with specific root length,specific root surface area,and fine root length density.P.bambusoides and P.glauca had higher fine root biomass and root tissue density,while P.bissetii and O.lubricum had higher specific root length and specific root surface area.(3)Fine root biomass,total root length,root surface area,root volume,and fine root length density were significantly and positively correlated with contents of soil organic matter and total N.The content of available K made the highest contribution(34.2%)to the fine root morphological variation.P.bambusoides and P.glauca have good environmental adaptability and can be effectively used for urban greening in northern China.An appropriate increase in the fertility of top soil is beneficial to the growth of fine roots.