滨海盐碱地人工刺槐绒毛白蜡混交林的根系分布与细根生长  

Root Distribution and Fine Root Growth in Mixed Plantation of Robinia pseudoacacia and Fraxinus velutina in Coastal Saline-Alkali Area

作　　者：杜振宇[1] 刘方春[1] 马丙尧[1] 董海凤[2] 马海林[1] 

机构地区：[1]山东省林业科学研究院,济南250014 [2]山东农业大学资源与环境学院,泰安271018

出　　处：《林业科学》2014年第3期10-15,共6页Scientia Silvae Sinicae

基　　金：山东省科技发展计划项目"黄河三角洲人工刺槐林更新改造技术研究"(2010GNC10942);山东省农业重大应用技术创新项目"黄河三角洲盐碱化土地高效利用模式配置研究"

摘　　要：在黄河三角洲盐碱地人工刺槐绒毛白蜡混交林内分别选择3株刺槐和绒毛白蜡标准木,在距离这6株标准木树干水平方向0 ～50,50 ～100,100 ～150,150 ～200和200 ～250 cm这5个距离范围内,按0 ～20,20 ～40和40 ～60 cm将土壤分为3个垂直层次,采用分层分段挖掘法分别获取根样,研究刺槐和绒毛白蜡根系的空间分布格局和细根生长特征.结果表明：这2种林木的根系构成以大于5 mm的粗根为主,绒毛白蜡的根系生物量显著高于刺槐,绒毛白蜡和刺槐根系在0～ 20 cm土层中的生物量分别占根系总生物量的59.8％和83.6％;绒毛白蜡的0～2,2～5和大于5 mm径级根系的水平分布距离均明显大于刺槐;2树种的大于5 mm粗根主要分布在距树干0～100 cm距离内,而较细的根系则主要分布在50 ～100 cm距离内;绒毛白蜡细根的生物量、根长、表面积和活力显著大于刺槐细根.绒毛白蜡在滨海盐碱立地条件下较刺槐具有更强适应能力.The root distribution and growth were studied in mixed plantation of Robinia pseudoacacia and Fraxinus velutina in coastal saline-alkali area of the Yellow River delta. The root samples were collected by excavating the soils at different horizontal distances of 0 -50 cm, 50 - 100 cm, 100 - 150 cm, 150 -200 cm , and 200 -250 cm from stem, and at depths of 0 -20 cm, 20 -40 cm and 40 -60 cm, respectively. The results showed that the root systems of both R. pseudoacacia and F. velutina were mainly consisted,of the roots with diameters larger than 5 mm, which accounted tot 59. 8% and 83. 6% in the soil layers of 0 - 20 cm for R. pseudoacacia and F. velutina, respectively. The horizontal distribution distances of F. velutina roots of different diameter classes were evidently longer than those of R. pseudoacacia. The roots with diameters larger than 5 mm mainly distributed within 0 - 100 cm while the smaller roots less than 5 mm diameter were in 50 - 100 cm from stem. The length, surface area, volume and average diameter, activity of fine roots of F. velutina were significantly higher than those of R. pseudoacacia. The study reveals a mechanism why F. velutina has stronger adaptability in coastal saline soils than R. pseudoacacia.

关 键 词：刺槐 绒毛白蜡 根系生物量 空间分布 细根 

分 类 号：S728.5[农业科学—林木遗传育种] S718.5[农业科学—林学]