2024年7月17日 星期三
不同马尾松林下光环境中油茶叶片特征和光合特征比较及其与主要环境因子的相关性
Comparisons on leaf and photosynthetic characteristics of Camellia oleifera in different understory light environments of Pinus massoniana and their correlations with major environmental factors
2022年 第31卷 第6期 页码[25-33]    下载全文[4MB]  
摘要

以光下无遮挡处为对照(光照强度1 719 μmol·m-2·s-1),对马尾松(Pinus massoniana Lamb.)林缘(光照强度859 μmol·m-2·s-1)和林内(光照强度181 μmol·m-2·s-1)10年生油茶(Camellia oleifera Abel)的叶片和光合特征进行研究,对3种林下光环境中气温、空气水汽压亏缺和光合有效辐射的日变化进行比较,并对油茶叶片和光合特征指标与上述3个主要环境因子的相关性进行分析。结果表明:林缘油茶叶片的面积、周长、厚度、比叶面积、气孔密度和叶绿素含量均最高,且基本上显著(P<0.05)高于林内和对照,但气孔面积却显著低于林内和对照。在光合有效辐射为300~1 800 μmol·m-2·s-1时,林缘油茶叶片的净光合速率也明显高于林内和对照。供试3种林下光环境中,油茶叶片的最大净光合速率、表观量子效率、光饱和点和暗呼吸速率均在林缘最高、在林内最低,而光补偿点则在对照最高、在林内最低,且这5个指标在不同林下光环境间差异显著。从油菜叶片光合参数的日变化看,林内油茶叶片的净光合速率、气孔导度、蒸腾速率和水分利用效率在多数时刻最低,且3种林下光环境中这些指标的日变化趋势各异;3种林下光环境中油茶叶片胞间CO2浓度和气孔限制值在不同时刻无明显规律,且其日变化趋势恰好相反。3种林下光环境中气温、空气水汽压亏缺和光合有效辐射的日变化总体上表现为先升高后降低的趋势。相关性分析结果表明:油茶叶片净光合速率、蒸腾速率和气孔限制值与3个主要环境因子均呈显著或极显著正相关,其胞间CO2浓度和水分利用效率基本上与3个主要环境因子呈显著或极显著负相关,另外,比叶面积和气孔面积与光合有效辐射呈极显著正相关。综上所述,马尾松林缘油茶的叶片生长较好且光合能力较强。

Abstract

Taking the place without shelter under light as the control (illumination intensity of 1 719 μmol·m-2·s-1), leaf and photosynthetic characteristics of 10-year-old Camellia oleifera Abel in forest edge (illumination intensity of 859 μmol·m-2·s-1) and forest inside (illumination intensity of 181 μmol·m-2·s-1) of Pinus massoniana Lamb. were studied, and the diurnal variations of air temperature, air vapor pressure deficit, and photosynthetically active radiation in three understory light environments were compared, meanwhile the correlations of leaf and photosynthetic characteristic indexes of C. oleifera with above three major environmental factors were analyzed. The results show that area, circumference, thickness, specific leaf area, stomatal density, and chlorophyll content in leaf of C. oleifera in forest edge are all the highest, and are basically significantly (P<0.05) higher than those in forest inside and the control, but stomatal area is significantly lower than that in forest inside and the control. At the photosynthetically active radiation of 300-1 800 μmol·m-2·s-1, net photosynthetic rate of leaf of C. oleifera in forest edge is also evidently higher than that in forest inside and the control. In three test understory light environments, maximum net photosynthetic rate, apparent quantum yield, light saturation point, and dark respiration rate of leaf of C. oleifera are all the highest in forest edge, but the lowest in forest inside, while light compensation point is the highest in the control, but the lowest in forest inside, and these five indexes are significantly different among different understory light environments. From the diurnal variations of photosynthetic parameters of leaf of C. oleifera, net photosynthetic rate, stomatal conductance, transpiration rate, and water use efficiency of leaf of C. oleifera in forest inside are the lowest at most times, and the diurnal variation tendencies of these indexes in three understory light environments are different; intercellular CO2 concentration and stomatal limit value of leaf of C. oleifera in three understory light environments have no evident patterns at different times, and their diurnal variation tendencies are opposite. The diurnal variations of air temperature, air vapor pressure deficit, and photosynthetically active radiation in three understory light environments show a tendency to first increase and then decrease in general. The correlation analysis result shows that net photosynthetic rate, transpiration rate, and stomatal limit value of leaf of C. oleifera all show significant or extremely significant positive correlations with three major environmental factors, while its intercellular CO2 concentration and water use efficiency basically show significant or extremely significant negative correlations with three major environmental factors, in addition, specific leaf area and stomatal area show extremely significant positive correlations with photosynthetically active radiation. Taken together, the growth of leaf of C. oleifera in forest edge of P. massoniana are relatively good, and its photosynthetic ability is relatively strong.

关键词油茶; 林下光环境; 叶片特征; 光合特征; 环境因子; 相关性分析
Key wordsCamellia oleifera Abel; understory light environment; leaf characteristics; photosynthetic characteristics; environmental factor; correlation analysis
作者张亚琴1, 郭其强1, 罗丝琼1, 盘金文1, 姚珊1, 郭有燕2
所在单位1. 贵州大学林学院 贵州省森林资源与环境研究中心, 贵州 贵阳 550025; 2. 河西学院乡村振兴研究院, 甘肃 张掖 734000
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基金项目贵州省科学技术厅平台人才项目([2018]5261)