林分密度对侧柏人工林细根形态的影响  

Effects of stand density on fine root morphology in Platycladus orientalis plantations

作　　者：周伟[1] 陈信力[1] 李瑞霞[1] 闵建刚[1] 徐梅[1] 卢雯[1] 关庆伟[1] 

机构地区：[1]南京林业大学森林资源与环境学院,南京210037

出　　处：《林业科技开发》2012年第4期35-38,共4页China Forestry Science and Technology

基　　金：国家林业公益性行业科研专项"提高城市森林固碳能力的关键技术研究与示范"(编号:201104075)

摘　　要：以徐州林场50年生侧柏人工林为研究对象,采用挖掘法获取土壤根系样品,探究林分密度对侧柏人工林不同根序细根形态的影响。结果表明:细根的直径和根长随着根序上升而显著增大,而比根长则随着根序的上升而显著减小。低林分密度(1 679株/hm2)与中林分密度(2 250株/hm2)相比显著减小了表层土壤1、2级细根的平均直径和平均根长,亚表层土壤3级细根的根长,显著增大了亚表层土壤2级细根的平均比根长;高林分密度(3074株/hm2)比中林分密度显著增大了2级根的平均比根长。与高林分密度相比,低林分密度显著减小了表层土壤1、2级细根的平均直径,增大了亚表层土壤5级细根的平均直径。An experiment was conducted to study the effects of stand density on fine root morphology in 50-year Platycladus orientalis plantations in Xuzhou Forest Region. Result showed that, with the ascent of root orders, P. Orientalis＇s mean fine root diameter and length increased significantly （p 〈 0. 05 ）, while the mean SRL decreased significantly （p 〈 0.05 ）. Stand density had significant influence on root morphology and biomass for Platycladus orientalis plantations （p 〈 0. 05 ）. Compared with the medium stand density （2 250 trees/hm2）, the mean length and mean diameter of the first and second order roots of low-density stands（ 1 700 trees/hm2 ） in surface soil and the mean length of third order roots of low-density stands in subsurface soil were decreased significantly while the mean SRL of second order roots of low-density stands was in- creased significantly. The mean SRL of second order roots of high-density stands （ 3 074 trees/hm：： ） was increased signifi- cantly compared with the medium stand density. Compared with the high-density stand, the mean diameter of the first and second order roots of low-density stands in surface soil were decreased significantly and the fifth order roots of low-density stands was increased significantly.

关 键 词：林分密度 侧柏人工林 根序 细根形态 

分 类 号：S753.3[农业科学—森林经理学]