立竹密度对不同发笋期毛竹叶片功能性状的影响

Effects of bamboo forest density on leaf functional traits of Phyllostachys edulis at different shoot growth stages

【目的】探究长周期母竹留养模式下毛竹叶片功能性状对立竹密度的响应及在不同发笋期的变化,并筛选出适宜的经营密度。【方法】以漳平市长周期母竹留养经营模式下笋用毛竹林为研究对象,设置(1350±100)、(1950±100)、(2550±100)、(3150±100)株·hm^(-2)4个不同立竹密度处理组,选用传统经营模式下生产效益较优的笋用毛竹林作为对照组,分析立竹密度对不同发笋期毛竹叶片功能性状的影响。【结果】毛竹林的叶面积指数、叶平均倾角、全氮含量、全磷含量、全钾含量和叶绿素含量均在立竹密度为(2550±100)株·hm^(-2)时达到最高,且不同处理组间差异显著(P<0.05);各处理组的叶面积指数、叶平均倾角及全氮含量均在发笋前期达到最高,冠层开度和叶绿素含量在发笋盛期达到最高,全磷和全钾含量则在发笋后期达到最高;毛竹叶片各功能性状间存在显著相关性。【结论】在长周期母竹留养经营模式下,当立竹密度为(2550±100)株·hm^(-2)时,毛竹林的冠层结构得到显著改善,叶片的空间分布更加合理,且叶片养分及叶绿素含量显著提高。

【Objective】The response of leaf functional traits to bamboo density and their changes at different shoot growth stages were investigated in moso bamboo(Phyllostachys edulis)forest for edible shoot production under long-term female bamboo retention management model to work out the suitable management density.【Method】Moso bamboo forests for edible shoot production managed under long-term female bamboo retention model in Zhangping City were used as the study subject,four stand density treatment groups of(1350±100),(1950±100),(2550±100),and(3150±100)plant·hm^(-2)were established,and selected moso bamboo forests with superior production efficiency under the traditional management model as the control group,to evaluate the impacts of stand density on leaf functional traits of moso bamboo.【Result】The results showed that the canopy leaf area index,mean tilt angle,total nitrogen content,total phosphorus content,total potassium content and chlorophyll content of moso bamboo reached the highest values at the bamboo density of(2550±100)plant·hm^(-2),and there were significant differences among different treatment groups.Canopy leaf area index,mean tilt angle and total nitrogen content in leaves peaked at the early stage of bamboo shoot growth;diffuse non-interceptance and chlorophyll content reached the highest values at the full stage,while the contents of total phosphorus and total potassium were the highest at the late stage of bamboo shoot growth.There were significant correlations among the functional traits of moso bamboo leaves.【Conclusion】Under long-term female bamboo retention management model,bamboo density of(2550±100)plant·hm^(-2)was contributed to significantly improved canopy structure,more rational blade space distribution,and greater leaf nutrient and chlorophyll contents.