走马胎灰分对光的响应特征及其与生长指标的相关性

为探究光照强度和光质对走马胎(Ardisia giantifolia)灰分积累的影响，利用遮阳网和薄膜设定4个光照梯度(100%、60%、40%、20%全光照)和4种光质(绿、白、蓝、红)，分析了基径、株高以及生物量的响应特征，以及灰分与生长指标的关系。结果表明，走马胎灰分含量在绿光下随着光照强度的减弱而呈减少的趋势，在白光下随着光照强度的减弱呈现“低-高-低-高”的波动变化，在蓝光或红光下没有显著变化；在100%光照强度下，白光的灰分含量最低，与其余光照强度存在显著差异; 在60%、40%、20%光照强度下，光质对走马胎灰分含量的影响不显著。走马胎灰分含量与株高、基径和生物量间不存在明显的相关性；随着光照强度的减弱，走马胎的株高、基径以及生物量均呈现增加的趋势，且在白光下达到最大。因此，光照对走马胎灰分的积累和生长指标均有影响，种植走马胎时要选择适当遮荫强度或郁闭度较高的林型。

Light Response Characteristics of Ash in Ardisia giantifolia and Its Correlation with Growth Indexes

In order to understand the effect of light on ash accumulation of Ardisia giantifolia, four light intensities (100%, 60%, 40% and 20% natural light intensity) and four light qualities (green, white, blue and red light) were set by using sunshade net and film, the response characteristics of height, basal diameter and biomass of A. giantifolia under different treatment conditions was analyzed, and the relationship between ash content and growth indexes was studied. The results showed that with the weakening of light intensity, the ash content of A. giantifolia decreased under green light with the decrease of light intensity, showing a “low-high-low-high” change trend under white light. Moreover, there was no significant change under blue light or red light. The ash content of A. giantifolia was the lowest under white light and 100% light intensity, showing significantly differences with that of the rest light intensity. At 60%, 40% and 20% natural light intensity, light quality had no significant effect on ash content of A. giantifolia. The ash content had no significant correlation with plant height, basal diameter and biomass of A. giantifolia. With the decrease of light intensity, the plant height, basal diameter and biomass of A. giantifolia increase, and reach maximum under white light. Therefore, it was suggested that light had effect on ash accumulation and growth index of A. giantifolia, and it was necessary to choose the forest type with proper shade intensity or canopy density when planting.