中国东部3个地带性森林的叶片功能属性及其关联

Leaf functional traits and correlations in three zonal forests in eastern China

以中国东部纬度梯度上3种典型森林(神农架、塞罕坝、呼中)为对象,分析不同生活型植物的叶厚、叶面积、比叶面积和叶干物质含量4个主要叶属性随纬度的变化规律及各属性间的关联,以此研究植物主要叶片属性对环境的适应机制。结果显示,随着纬度的增加,叶厚度先降后增,叶面积显著降低,神农架的叶面积值是塞罕坝的2.3倍,是呼中的5.8倍,叶干物质含量无显著变化,比叶面积先增后降。叶厚度与比叶面积呈极显著负相关,与叶干物质含量呈极显著正相关,比叶面积与叶干物质含量呈极显著负相关。林型对叶厚度、叶面积、比叶面积变异的解释率最大,分别为75.99%、80.23%、59.96%,生活型对叶干物质含量变异的解释率最大(86.79%),不同生活型植物比叶面积与叶干物质含量间的关联随纬度增加无明显变化,且保持负相关关系不变。研究结果表明不同林型和生活型对叶属性的变异起着重要的调控作用,而叶片对外界环境的适应性差异,导致了不同气候带上森林叶片功能属性的差异。

To study the adaptation mechanisms of leaf traits to the environment,three typical forests(Shennongjia,Saihanba,Huzhong)along a latitudinal gradient in eastern China were used to analyze variations in leaf thickness,leaf area,specific leaf area,and leaf dry matter content,as well as their relationships between different life forms and attributes.Results showed that,with latitude increasing,leaf thickness decreased at first and then increased;leaf area decreased significantly,with the leaf area of Mt.Shennongjia found to be 2.3 times higher than that of Mt.Saihanba and 5.8 times higher than that of Mt.Huzhong;leaf dry matter content did not change significantly;and specific leaf area increased at first and then decreased.Leaf thickness was significantly negatively correlated with specific leaf area and significantly positively correlated with leaf dry matter content.Specific leaf area was significantly negatively correlated with leaf dry matter content.Forest type explained most of the variation in leaf thickness,leaf area,and specific leaf area,accounting for 75.99%,80.23%,and 59.96%of the variation,respectively,whereas life form explained most of the variation in leaf dry matter content,explaining 86.79%of the variation.With increasing latitude,the correlation between specific leaf area and leaf dry matter content of different life forms did not change significantly,with the negative correlation remaining unchanged.Our study showed that both forest type and life form played an important role in regulating leaf trait variation.Thus,differences in leaf adaptability to the external environment can lead to differences in forest leaf traits in different climatic zones.