喀斯特森林木本植物叶片功能性状对土壤特性的响应

Response of Leaf Functional Traits of Woody Plants to Soil Characteristics in Karst Forests

摘要:

为明确喀斯特森林植物叶片功能性状对土壤特性的响应，采用样地与样线相结合的方法调查茂兰喀斯特森林的木本植物群落，计算不同地形木本植物叶片加权平均性状值，运用单因素方差分析和冗余分析不同地形植物叶片功能性状的差异及其与土壤特性的关系。结果表明, 在生长型(常绿、落叶)和群落水平上，植物叶片功能性状在不同地形间存在显著差异(P<0.05)，其中叶面积最为敏感，对生境的响应明显，常绿植物的叶厚度大于落叶植物，比叶面积则相反，而叶绿素含量差异不显著(P>0.05)。不同地形间土壤特性差异显著(P<0.05)，漏斗地形土壤的田间持水量、毛管孔隙度、全氮含量、全磷含量及有机质含量较高，土壤肥力最佳，槽谷和阴坡次之，而阳坡地段土壤相对贫瘠。不同地形植物叶片功能性状与土壤特性间具有相关性，但不同地形土壤特性对叶片功能性状变异的解释率不同，影响植物叶片功能性状的主要土壤特性为有机质含量、全氮含量、全磷含量、田间持水量和土壤容重。茂兰喀斯特森林不同地形植物叶片功能性状和土壤特性的差异较大，随着土壤特性的改变，叶片功能性状的响应特征不同，这有利于林区物种共存及生物多样性维持。

Abstract:

In order to understand the response of plant leaf functional traits to soil characteristics in karst forest, the woody plant communities in Maolan National Reserve were investigated by using the methods of sample plot and transversal, the weighted average leaf traits of woody plants in different terrain were calculated, and the relationship between leaf functional traits and soil characteristics analyzed by One-Way ANOVA and redundancy. The results showed that there were significant differences in plant leaf functional traits between different terrains at the growth type (evergreen/defoliate) and community level (P<0.05), among which the leaf area was the most sensitive, its response to habitat was obvious. However, leaf thickness of evergreen plants was greater than that of deciduous plants, while specific leaf area was the opposite, and the difference in chlorophyll content is not significant (P>0.05). There were significant difference in soil characteristics among different terrains (P<0.05). The field water capacity, capillary porosity, contents of total nitrogen, total phosphorus and organic matter of soil on funnel terrain were higher, and the soil fertility was the best, followed by valley and shady slope, while the soil on sunny slope was relatively barren. There was a correlation between leaf functional traits and soil characteristics in different terrain, but the interpretation rate of leaf functional traits variation was different in different terrain soil characteristics. The main soil characteristics affecting leaf functional traits were organic matter content, total nitrogen content, total phosphorus content, field water capacity and soil bulk density. Therefore, leaf functional traits and soil characteristics differ greatly in different terrain of Maolan karst forest. With the change of soil characteristics, leaf functional traits have different response characteristics, which is conducive to species coexistence and biodiversity maintenance in forest area.