Comparing growth and fine root distribution in monocultures and mixed plantations of hybrid poplar and spruce

编号 zgly0000818190

文献类型 期刊论文

文献题名 Comparing growth and fine root distribution in monocultures and mixed plantations of hybrid poplar and spruce

作者 Lahcen  Benomar  Annie  DesRochers  Guy  R.  Larocque 

作者单位 Chaire  industrielle  CRSNG-UQAT-UQAM  en  aménagement  forestier  durable.  Université  du  Québec  en  Abitibi-Témiscamingue  Natural  Resources  Canada 

母体文献 林业研究: 英文版 

年卷期 2013(2)

页码 247-254

年份 2013 

分类号 S 

关键词 Picea  glauca  Populus  balsamifera  ×  trichocarpa  P  maximowiczii  ×  balsamifera  mixed-species  monoculture  spacing  fine  root 

文摘内容 Disease prevention, biodiversity, productivity improvement and ecological considerations are all factors that contribute to increasing interest in mixed plantations. The objective of this study was to evaluate early growth and productivity of two hybrid poplar clones, P. balsamifera x trichocarpa (PBT) and P. maximowiczii x balsamifera (PMB), one improved family of Norway spruce (Picea glauca (PA)) and one improved family of white spruce (Picea abies (PG)) growing under different spacings in monocultures and mixed plots. The plantations were established in 2003 in Abitibi-Témiscamingue, Quebec, Canada, in a split plot design with spacing as the whole plot factor (1 × 1 m, 3 × 3 m and 5 × 5 m) and mixture treatments as subplot factor (pure: PBT, PMB, PA and PG, and 1: 1 mixture PBT: PA, PBT: PG, PMB: PA and PMB: PG). Results showed a beneficial effect of the hybrid poplar-spruce mixture on diameter growth for hybrid poplar clones, but not for the 5 × 5 m spacing because of the relatively young age of the plantations. Diameter growth of the spruces decreased in mixed plantings in the 1 × 1 m, while their height growth increased, resulting in similar aboveground biomass per tree across treatments. Because of the large size differences between spruces and poplars, aboveground biomass in the mixed plantings was generally less than that in pure poplar plots. Leaf nitrogen concentration for the two spruce families and hybrid poplar clone PMB was greater in mixed plots than in monocultures, while leaf nitrogen concentration of clone PBT was similar among mixture treatments. Because of its faster growth rate and greater soil resources demands, clone PMB was the only one showing an increase in leaf N with increased spacing between trees. Fine roots density was greater for both hybrid poplars than spruces. The vertical distribution of fine roots was insensitive to mixture treatment.