摘要
为探索沙棘幼苗对光照强度的适应性,通过设置100%光照强度、60%光照强度、20%光照强度3个光照梯度,分析沙棘幼苗的生长、光合特性及生物量分配特征对不同光环境的响应。结果表明:光照显著促进沙棘幼苗的生长,苗高、基径、冠幅、叶长、叶宽、叶面积、净光合速率等指标均在100%光照强度下最大,而且均随光照强度的减弱而减小;沙棘幼苗的根、茎、叶和单株生物量均在100%光照强度下最大;根冠比、叶生物量比、茎生物量比及根生物量比在3种光环境下无显著差异;沙棘幼苗通过改变光合特性和生物量积累来适应光环境的变化,其中光照强度的降低限制了生物量的积累,但并未显著改变生物量在地上和地下部分的分配比例,在3种光环境下生物量分配比例并无显著的改变;幼苗的比叶面积随着光照强度减弱而增大,在20%光照强度下达到最大值。
In order to explore adaptation of Hippophae rhamnoides seedlings to light intensity, seedling growth, photosynthetic characteristics and biomass allocation in H. rhamnoides seedlings were investigated under different light intensities（100% of full sunlight, 50% of full sunlight, 20% of full sunlight）. The results show that lighting can signifi cantly promote seedling growth. Some indices of H. rhamnoides seedlings reach the highest values under100% light intensity treatment and reduce with light intensity decreased, including seedling height, basal diameter, crown width, leaf length, leaf width, leaf area and net photosynthetic rate. Root biomass, stem biomass, leaf biomass and total biomass of H. rhamnoides seedlings are the largest under 100% light intensity. Ratio of root to crown, leaf biomass ratio, root biomass ratio and stem biomass ratio have no signifi cant difference under the three light intensities. Photosynthetic characteristics and biomass accumulation of H. rhamnoides seedlings are regulated to adapt to light environment change, among which biomass accumulation is confi ned by decrease of light intensity. However, allocation ratio of aboveground biomass and under-ground biomass are not signifi cantly influenced. Changes in biomass allocation ratio of H. rhamnoidesseedlings are not significant under different light intensities. Specific leaf area is increased with decrease of light intensity, and reaches peak value under the condition of 20% light intensity.
出处
《经济林研究》
北大核心
2014年第3期48-53,共6页
Non-wood Forest Research
基金
国家林业公益性行业科研专项(201004068)
关键词
沙棘
光照强度
幼苗生长
光合特性
生物量分配
Hippophae rhamnoides
light intensity
seedling growth
photosynthetic characteristics
biomass allocation
