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作 者 ：贺书珍 1，王得祥 2，杨改河 3，李 刚4*，秦晓威 3，杨俊杰4，权 悠4，王 琛4

期 刊 ：西北植物学报 2012年 1期 页码：180~186

关键词：太白山；林隙；牛皮桦；草本植物；区域物种丰富度；局域物种丰富度；

Keywords:Taibai Mountain, canopy gap, Betula utilis, herbaceous plant, regional species richness, local species richness,

摘 要 ：以太白山牛皮桦林林隙内草本植物总数为区域物种丰富度，分别采用0.25 m ²和1 m ²样方重复抽样的丰富度平均值为局域物种丰富度，来探讨区域物种多样性变异对局域多样性的影响。结果显示：（1）0.25 m ²和1 m ²局域物种丰富度与区域物种丰富度显著相关（r=0.791和r=0.861），且随区域物种丰富度的增加而增加；同时，林隙面积也能显著增加局域和区域物种丰富度。（2）控制林隙面积变量的多元回归分析显示，0.25 m ²和1 m ²局域物种丰富度与区域物种丰富度存在显著线性回归关系（R ²=0.642和R ²=0.743）；方差分离分析显示，林隙面积仅能解释0.25 m ²和1 m ²局域物种丰富度变异的4.0%和4.4%，而区域物种丰富度能解释25.8%和35.3%。研究表明，区域物种丰富度变异在一定程度上决定着局域物种丰富度的组成。

Abstract:It has been widely confirmed that canopy gap disturbances can promote species richness of forest communities.However,whether plant assemblage within a canopy gap is constrained by local or regional processes remains a contentious issue in plant ecology.To investigate the contrasting roles of local processes and regional processes,we examined the relationships between the number of herbaceous plant species at two small-scales (in 0.25 m ² and 1 m ² quadrats) within the gap and the whole herbaceous plant species in the surrounding gap in the Betula utilis forest of Taibai Mountain.The results showed that:(1)species richness at 0.25 m ² and 1 m ² local scales significantly correlated with the number of available species in the surrounding gap (r=0.791 and r=0.861).And the two local-scales species richness showed a positive function of regional species richness,respectively.But the local and regional species richness significantly increased with increasing gap sizes,which may generate a spurious relationship between local and regional species richness.(2)The significant positive local-regional relationship was persisted controlling for the effect of gap size in multiple regression (R ²=0.642 for 0.25 m ² scale and R ²=0.743 for 1 m ² scale).Moreover,analysis of variance depicted that gap size only explained 4.0% and 4.4% of the variation in local species richness at 0.25 m ² and 1 m ² quadrats,respectively;While,regional species richness accounted for 25.8% and 35.3% after gap size was controlled,respectively.These results suggested that local-scale species richness can be constrained by regional species richness in the surrounding canopy gaps.

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