生态学报2017，Vol.37Issue(9)：3065-3073,9.DOI:10.5846/stxb201601150100
间伐对黄龙山油松中龄林细根空间分布和形态特征的影响
Effects of thinning intensity on fine root biomass and morphological characteristics of middle-aged Pinus tabulaeformis plantations in the Huanglong Mountains
摘要
Abstract
Pinus tabulaeformis plantations play an important role in local water and soil conservation and ecological protection in the Loess Plateau.Because of the large surface area,short life span,and rapid turnover,fine root systems were considered an important part in material cycling,energy transportation,and soil and water conservation of the forest ecosystem.This study was conducted in a middle-aged P.tabulaeformis plantation,located in the Huanglong Mountains,south of Loess Plateau,China.Thinning was performed on three occasions in 2008 following afforestation:light thinning,medium thinning,and heavy thinning.Three replicates of thinned and un-thinned treatments (20 m×30 m) were selected in our research.Basic data of fine root biomass and morphological characteristics were collected from three soil depths (0-20 cm,20-40 cm,and 40-60 cm) via root drilling methods.The results showed that fine root biomass increased with increasing thinning intensity up to the medium thinning treatment and then decreased in the heavy thinning treatment.Fine root biomass in the 0-20cm soil layer decreased significantly (P＜0.05) under heavy thinning intensity compare with other treatments.The proportions of fine root biomass in the 20-40-cm and 40-60-cm soil layers increased with increasing thinning intensity.The differences in root length density and root surface area density between different thinning intensities and different soil layers were significant (P ＜ 0.05),and exhibited a similar trend as the finc root biomass.With increased thinning intensity,specific root length and specific surface area of fine roots increased,and the differences were significant under heavy thinning (P＜0.05).Light and medium thinning had a significant effect on finest diameter fine roots (0-1.0 mm),but no significant effect on fine roots (1.0-2.0 mm) (P＜0.05),whereas heavy thinning had a significant effect on all roots (0-20 cm) (P＜0.05).Fine roots may be distributed in the deep soil layer after thinning.Compared with fine roots,the finest ones were more sensitive to different thinning intensities.In this study,fine root biomass (1022.43 g/m2),along with the root length density and root surface area,peaked at the medium thinning intensity,which could be the appropriate silviculture practice for tree growth.关键词
间伐强度/油松中龄林/细根/生物量/形态特征Key words
thinning intensity/middle-aged P.tabulaeformis plantation/fine root/biomass/morphological characteristics引用本文复制引用
尤健健,张文辉,邓磊,余碧云,李罡,何婷,樊蓉蓉..间伐对黄龙山油松中龄林细根空间分布和形态特征的影响[J].生态学报,2017,37(9):3065-3073,9.基金项目
国家林业局全国森林经营基础研究项目(1692016-03) （1692016-03）
黄土高原松栎林多功能近自然经营作业法及其效益监测研究 （）
