紫金山3种优势乔木细根功能性状的序级变化特征  

Variations in functional traits between different orders of fine roots of three dominant trees in Zijin mountain

作　　者：牛莹莹 袁在翔 谷雨晴 吴茜 邹朋峻 关庆伟[1,2] NIU Yingying;YUAN Zaixiang;GU Yuqing;WU Qian;ZOU Pengjun;GUAN Qingwei(College of Ecology and the Environment,Nanjing Forestry University,Nanjing 210037,Jiangsu,China;Co-Innovation Center for the Sustainable Forestry in Southern China,Nanjing Forestry University,Nanjing 210037,Jiangsu,China;Research Institute of Tropical Forestry,Chinese Academy of Forestry,Guangzhou 510520,Guangdong,China)

机构地区：[1]南京林业大学生态与环境学院,江苏南京210037 [2]南京林业大学南方现代林业协同创新中心,江苏南京210037 [3]中国林业科学研究院热带林业研究所,广东广州510520

出　　处：《中南林业科技大学学报》2024年第7期54-63,共10页Journal of Central South University of Forestry & Technology

基　　金：江苏省林业科技创新与推广项目(LYKJ[2022]04);江苏省高校优势学科建设工程项目(PAPD)。

摘　　要：【目的】明晰紫金山3种优势乔木细根功能性状在序级间的变化特征,为深入理解不同根序细根在地下生理生态过程中的作用提供理论依据。【方法】以紫金山3种优势乔木糙叶树、朴树和枫香为对象,采用随机区组设计设置3个20 m×20 m的样方,采集优势树种的细根,分析不同树种细根直径、比根长、比表面积、根组织密度、C、N及P含量等功能性状随序级的变化特征。【结果】1)树种对细根形态性状和化学性状都有显著影响,而序级只对细根直径、比根长、比表面积、细根N、P含量和C/N有显著影响。2)随着序级升高,3种优势乔木的细根直径和C/N呈现增加趋势,比根长、比表面积、N含量和P含量整体呈现减小趋势,根组织密度和C含量随序级增加没有明显的变化规律。3)在1~5级根中,朴树的直径最小,比根长和比表面积最大;糙叶树的根组织密度最大;朴树的C含量最高;枫香的C/N最小。在1级根中,糙叶树的N含量最高,朴树的P含量最高。糙叶树和枫香的细根生物量随着序级升高而增加,朴树的1级根生物量大于2、3级根生物量。4)主成分分析表明,3种优势乔木的细根功能性状分为两个变异维度,糙叶树偏向于资源获取型,朴树偏向于自主觅食资源获取型,而枫香偏向于不同策略的权衡。【结论】细根功能性状和多维度根系策略在树种之间存在差异,表明糙叶树和朴树细根对养分的获取效率较高,枫香细根养分获取效率较低;但枫香细根的分解速率可能快于糙叶树和朴树。【Objective】In order to provide a theoretical basis for understanding the underground physiological and ecological processes mediated by fine roots in different root orders,the variations of fine root functional traits of three dominant trees in Zijin mountain were investigated.【Method】Three 20 m×20 m plots were set up by using a random block design in Zijin mountain.Inside the plots,the fine roots of three dominant tree species,including Aphananthe aspera,Celtis sinensis and Liquidamabar formosana,were collected.The root diameter,specific root length,specific surface area,root tissue density,C content,N content,and P content of these fine roots in orders were quantified and compared.【Result】1) Species identity significantly affected all parameters mentioned above,while fine root order only had significant effects on fine root parameters,i.e.root diameter,specific root length,specific surface area,N content,P content,and C/N ratio.2) With the increase of fine root order,root diameter and C/N increased,specific root length,specific surface area,N content,and P content decreased,while root tissue density and C content had no response.3) Among the three species,C.sinensis had the smallest diameter,the largest specific root length and specific surface area,and the highest C content,A.aspera had the highest root tissue density,and L.formosana had the smallest C/N in 1^(st)-5^(th) root orders;A.aspera had the highest N content,and the of C.sinensis had the highest P content in the 1^(st) root order.In addition,the fine root biomass of A.aspera and L.formosana increased with the increase of root order,and the 1^(st) order root biomass in C.sinensis was higher than that of the 2^(nd) and 3^(rd) grade roots.4) The principal component analysis showed that the fine root functional traits of the three tree species could be divided into two variation dimensions.A.aspera preferred resource acquisition type,C.sinensis preferred autonomous foraging resource acquisition type,and L.formosana preferred the trade-off of

关 键 词：功能性状 细根形态 化学性状 优势树种 细根序级 

分 类 号：S718.5[农业科学—林学]