地形、邻株植物及自身大小对红楠幼树生长与存活的影响  

Effects of topography, neighboring plants and size-dependence of Machillus thunbergii on sapling growth and survivorship

作　　者：童跃伟[1,3] 项文化[1,2] 王正文[3] Walter Durka Markus Fischer 

机构地区：[1]中南林业科技大学生命科学与技术学院,长沙410004 [2]湖南会同杉木林生态系统国家野外科学观测研究站,长沙410004 [3]中国科学院沈阳应用生态研究所,沈阳110016 [4]Department Community Ecology, Helmholtz-Centre for Environmental Research-UFZ, Halle, 06120, Germany [5]Institute of Plant Sciences, University of Bern, Bern, CH-3013, Switzerland

出　　处：《生物多样性》2013年第3期269-277,共9页Biodiversity Science

基　　金：国家自然科学基金项目(NSFC30710103907)、国家自然科学基金项目(NSFC30930005);德国自然科学基金项目(DFGFOR891)

摘　　要：在山地森林中,树木生长不仅受地形的影响,也与邻株植物存在各种相互作用,而且具有个体大小依赖性。然而这些影响都具有物种特异性,即不同物种即使在同类地形或与同种植物相邻也会受到不同乃至相反的影响。此外,不同物种个体生长的自身大小依赖性也存在差异。作者利用中欧合作项目"中国亚热带森林生物多样性与生态系统功能实验研究(BEF)"实验样地,以渐危的常绿阔叶木本植物红楠(Machilus thunbergii)为研究对象,连续两年观测了存活的1,452株红楠幼树基径和树高,分析坡向和坡度等地形、邻株植物丰富度及其功能群组成、红楠自身大小对红楠幼树生长和存活率的影响。结果表明:(1)红楠幼树位于阴坡时比位于阳坡具有更高的生长速率和存活率,而坡度只对树高生长量有显著影响;(2)邻株植物物种丰富度对红楠幼树的基径、树高和存活率影响不显著;(3)邻株植物功能类型对红楠幼树生长具有极显著的影响,影响程度大小依次为落叶阔叶型>落叶阔叶与常绿阔叶的混交型>常绿阔叶型>常绿针叶型,而对存活率无显著影响;(4)红楠幼树的生长与自身大小呈正相关幂函数关系,即基径和树高的生长速率都会随着其自身大小的增加而增加。可见,构建树木生长模型,不仅要考虑地形等环境因子差异,而且要充分考虑邻株植物的功能类群差异、邻株植物相互作用的性质和程度,以及自身个体大小等因素,为渐危和濒危树种的保护提供更为可靠的理论依据。Growth and survivorship of Machillus thunbergii saplings in mountain forest are likely to be affected by topographical factors, biotic interactions with neighbouring plants, and individual size. However, such effects are always species- and site-specific, and may influence how plant species diversity contributes to ecosystem productivity. This study aimed to examine how individual growth and survivorship of Machilus thunbergii saplings are affected by： （1） topographical factors, such as aspect and inclination of slope, （2） species richness and type of neighboring plants, and （3） individual plant size. The experiment was conducted in the framework of BEF-China, a manipulated subtropical forest site in China. A total of 265 plots of 25.82 m × 25.82 m were planted with 1, 2, 4, 8, 16 or 24 different tree species. Each plot contained 400 trees arranged in a rectangular pattern with 1.29 m distance between individuals. In 2010 we added 16 individuals of M. thunbergii to each plot. These 16 individuals were planted in two rows along the western edge of the plots, with each individual in the center of 4 adjacent trees. Height and basal diameter of 1,452 surviving Machilus saplings were measured in June 2011 and 2012. ANOVA and Duncan’s multiple comparison tests were used to analyze the effects of both topography and of neighbouring plants, and linear regression was used to test size-dependence of growth. We found that Machilus saplings on shady slopes grew faster and had higher survival rates than those on sunny slopes, while the height increment of Machilus on plots with a mild incline was greater than that on steep slopes. Richness of neighboring plant species had an insignificant effect on Machilus sapling growth and survival rate; while the type of neighbouring species had different effects on Machilus sapling growth, but no effect on survival rate. Deciduous broadleaved species had the greatest effect on growth, followed by a mixture of deciduous and evergreen broadleaved species, followed by everg

关 键 词：中国亚热带森林生物多样性与生态系统功能实验研究 功能类群 MACHILUS thunbergii 邻株植物效应 大小依赖 物种丰富度 地形 树木生长模型 

分 类 号：Q948[生物学—植物学]