北京林业大学学报2016，Vol.38Issue(8)：45-53,9.DOI:10.13332/j.1000-1522.20160018
密度调整对太岳山华北落叶松人工林冠层结构及林下植被的影响
Influence of density adjustment on canopy structure and understory vegetation of the Larix principis-rupprechtii plantation in Taiyue Mountain, Shanxi, China
摘要
Abstract
Larix principis-rupprechtii plantations are major public welfare forests in Taiyue Mountain, North China. However, the stand quality of L. principis-rupprechtii plantations is limited due to the high stand density. Density adjustment is therefore of great significance in improving the quality of plantations, increasing the understory species diversity and maintaining ecosystem functions. In order to investigate the influence of density adjustment on canopy structure, light environment and species diversity of understory vegetation, a thinning experiment was conducted in a 35-year-old L. principis-rupprechtii plantation with heavy ( 50%) , medium ( 30%) and light ( 20%) intensities and unthinned plots as control in Taiyue Mountain. The results showed that:1) density adjustment had significant effects on the forest canopy structure and light environment of understory. The spatial heterogeneity of canopy structure was increased following the density adjustment. After thinning treatments at 20%, 30% and 50%intensities, the canopy leaf area index ( LAI ) was reduced by 18. 25%, 25. 76% and 37. 50%, respectively, compared to the control, while the openness was increased by 17. 45%, 17. 45% and 17. 45%, respectively. Photosynthetic photon flux density (PPFD) was 1. 3, 1. 4 and 2. 1 times that of the control, respectively. 2 ) The number of understory species and their quantities were increased by changing the structural characteristics of the understory community. The highest species diversity and the most complex structure appeared in the 30% thinning treatment. 3) Correlation analysis and CCA sorting analysis showed a significant correlation between the canopy structure and diversity of understory vegetation. The diversity of herb layer species had a significantly negative correlation with LAI, which was the main factor affecting species composition in the herb layer.关键词
密度调整/冠层结构/光环境/物种多样性Key words
density adjustment/canopy structure/light environment/species diversity分类
农业科技引用本文复制引用
田平,韩海荣,康峰峰,程小琴,朱江,周文嵩..密度调整对太岳山华北落叶松人工林冠层结构及林下植被的影响[J].北京林业大学学报,2016,38(8):45-53,9.基金项目
林业公益性行业科研专项(201404213)。 （201404213）
