坡向对川西亚高山彩叶林群落树种种内和种间竞争的影响  

Effects of Slope Direction on the Intraspecific and Interspecific Competition in Subalpine Color-Leaved Forests in Western Sichuan,China

作　　者：陈娟[1,2,3] 张小晶 李巧玉 陶建平[1,2,3] CHEN Juan;ZHANG Xiao-jing;LI Qiao-yu;TAO Jian-ping(Key Laboratory of Eco-environments in Three Gorges Reservoir Region,Chongqing 400715,China;Key Laboratory of Plant Ecology and Resources Research in Three Gorges Reservoir Region,Chongqing 400715,China;School of Life Sciences,Southwest University,Chongqing 400715,China)

机构地区：[1]三峡库区生态环境教育部重点实验室,重庆400715 [2]重庆市三峡库区植物生态与资源重点实验室,重庆400715 [3]西南大学生命科学学院,重庆400715

出　　处：《西南大学学报（自然科学版）》2021年第2期53-62,共10页Journal of Southwest University(Natural Science Edition)

基　　金：国家重点研发计划项目(2017YFC0505003).

摘　　要：研究不同坡向上群落物种竞争和生长的关系,对于阐明不同环境梯度上群落差异和景观差异具有重要意义.以四川省阿坝藏族羌族自治州位于同一海拔但坡向相反的天然次生彩叶林为研究对象,采用Hegyi单木竞争模型分析了不同坡向上彩叶林群落物种的种内种间竞争和群落物种多样性及生长的关系.结果显示:1)阴坡上林分密度低于阳坡,但是物种多样性指数却高于阳坡;2)阴坡上群落种内种间竞争都高于阳坡;3)阴坡群落优势物种青榨槭和青麸杨种内竞争强度小于种间竞争,阳坡群落所有优势物种的种内竞争都强于种间竞争强度;4)阴坡物种种内竞争强度随林木胸径和树高的增加而减少,阳坡上却随着林木胸径和树高的增加而增加.这些结果揭示了坡向通过影响植物竞争与林木生长的关系显著改变了川西亚高山地区不同坡向上彩叶林群落的物种组成和结构.Although many studies have shown that species competition significantly influences the species coexistence and composition of forest communities,effect of slope direction on the intraspecific and interspecific competitions in subalpine forests is still poorly understood.In this study,we investigated the relationship between species competition and tree growth in color-leaved forests with opposite slope directions in the Ngawa(Aba)Tibetan and Qiang Autonomous Prefecture in western Sichuan,China.Results showed that stand density of the north-facing slope was lower than that of the south-facing slope,but its species diversity index was higher than that of the south-facing slope;that both interspecific competition and intraspecific competition intensities of the north-facing slope were higher than those of the south-facing slope;intensity of intraspecific competition(A.davidii and Rhus potaninii)was lower than that of interspecific competition in the north-facing slope.Intensity of intraspecific competition was stronger than that of interspecific competition in the south-facing slope;and that intraspecific competition intensity decreased with increasing tree height and diameter at breast height(DBH)on the north-facing slope,but increased with it on the north-facing slope.Our results suggested that slope directions significantly changed the species composition and structure of color-leaved forest communities in the subalpine regions of Western Sichuan by influencing the patterns of species competitions.

关 键 词：坡向 彩叶林 Hegyi竞争指数 种内竞争 种间竞争 

分 类 号：S718.5[农业科学—林学]