南方典型红壤丘陵区泡桐幼苗根系的空间分布特征  

Root spatial distribution characteristics of Paulownia seedlings in typical red soil hilly region in southern China

作　　者：田卓 何建华 张帅普 代俊峰[1] 徐勤学[1] TIAN Zhuo;HE Jian-hua;ZHANG Shuai-pu;DAI Jun-feng;XU Qin-xue(Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology/Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area,Guilin University of Technology,Guilin,Guangxi 541004,China)

机构地区：[1]桂林理工大学广西环境污染控制理论与技术重点实验室/岩溶地区水污染控制与用水安全保障协同创新中心,广西桂林541004

出　　处：《西南农业学报》2023年第10期2200-2209,共10页Southwest China Journal of Agricultural Sciences

基　　金：国家自然科学基金项目(41907011);广西自然科学基金项目(2018GXNSFBA050013)。

摘　　要：【目的】分析南方红壤丘陵区白花泡桐[Paulownia fortunei(Seem.)Hemsl.]幼苗根系的空间分布及变异特征,为泡桐栽培及红壤丘陵区植被恢复提供参考依据。【方法】野外调查典型红壤丘陵区对重金属元素具有较强富集作用及可防治水土流失的白花泡桐幼苗不同直径(d<0.5 mm、0.5 mm≤d<2.0 mm、2.0 mm≤d<3.0 mm、3.0 mm≤d<5.0 mm和d≥5.0 mm)根系的空间分布规律,分析泡桐幼苗对土壤的适应能力。【结果】在垂直方向上,随着土层深度的增加,泡桐幼苗的根长、根表面积和比根表面积呈先增加后减少的变化趋势,根体积、根干重和根组织密度逐渐减少,比根长逐渐增加;<3.0 mm各径级根系的根体积、根表面积和<5.0 mm各径级根系的根长随着土层深度的增加均呈先增加后减少的变化趋势,其他径级根系的根体积、根表面积和根长逐渐减少。0≤土层深度(h)<10.0 cm土层根表面积和根体积的变异性均显著强于其他土层(P<0.05,下同),根干重的变异性显著强于20.0 cm≤h<50.0 cm各土层;40.0 cm≤h<50.0 cm土层中2.0 mm≤d<5.0 mm各径级根系的根长、根体积和根表面积变异性均显著强于其他土层。在不同水平位置上,<2.0 mm各径级根系的根长、根体积和根表面积在距树干最远的剖面均最大,≥2.0 mm各径级根系的根长、根体积和根表面积在树干所在的剖面均最大。各剖面间根长、根体积、根表面积、根干重、比根长、根组织密度和比根表面积的变异性均无显著差异(P>0.05);各径级根系根长、根体积和根表面积变异性均在距树干最远的剖面最强。【结论】白花泡桐幼苗根系主要集中分布在0~20.0 cm土层,具有明显的表聚现象,在栽培泡桐时,应重点关注0~20.0 cm土层土壤的理化性质,以保证泡桐根系对土壤水肥的高效吸收利用。【Objective】The purpose of the study was to analyze the spatial distribution and variation characteristics of Paulownia fortunei(Seem.)Hemsl.roots in the red soil hilly region in southern China,and to provide references for Paulownia cultivation and vegetation restoration in red soil hilly region.【Method】Taking P.fortunei(Seem.)Hemsl.seedlings with strong enrichment of heavy metal elements and prevention of soil erosion in a typical red soil hilly region as the research object,field investigation was used to investigate the spatial distribution pattern of P.fortunei(Seem.)Hemsl.roots in different diameters(d<0.5 mm,0.5 mm≤d<2.0 mm,2.0 mm≤d<3.0 mm,3.0 mm≤d<5.0 mm and d≥5.0 mm),and to analyze the adaptive ability of Paulownia to the soil.【Result】In the vertical direction,root length,root surface area and specific root surface area of Paulownia seedlings showed a trend of increasing and then decreasing with the increase of soil depth.Root volume,root dry weight and root tissue density decreased gradually,while specific root length increased gradually with soil depth.Root volume and root surface area for roots of<3.0 mm diameter levels and root length for roots of<5.0 mm diameter levels showed an increasing and then decreasing trend with soil depth,while root volume,root surface area and root length for other diameter roots decreased gradually.The variability of root surface area and root volume in 0≤soil depth(h)<10.0 cm soil layer was significantly stronger than that in other soil layers(P<0.05,the same as below),and the variability of root dry weight was significantly stronger than that in 20.0 cm≤h<50.0 cm different soil layers.The variability of root length,root volume and root surface area of roots of 2.0 mm≤d<5.0 mm diameter levels in 40.0 cm≤h<50.0 cm soil layer were significantly stronger than those in other soil layers.In different horizontal positions,root length,root volume and root surface area for roots of<2.0 mm diameter levels were the largest in the profile farthest from th

关 键 词：泡桐 红壤丘陵区 根系 空间分布 变异特征 

分 类 号：S732[农业科学—林学] S365