Jeong Hyungsoon, Cho Yong-Chan, Kim Eunsuk
School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Korea.
Conservation Center for Gwangneung Forest, Korea National Arboretum, Pocheon 11186, Korea.
AoB Plants. 2021 Sep 19;13(5):plab061. doi: 10.1093/aobpla/plab061. eCollection 2021 Oct.
Future environmental changes are projected to threaten plant populations near mountaintops, but plastic responses of plant traits that are related to demographic parameters may reduce the detrimental effects of altered environments. Despite its ecological significance, little is known about the intraspecific variation of plasticity in alpine plant species such as subsp. In this study, we investigated the plastic responses of plants at the early developmental stage from four natural populations in response to temperature and nitrogen deposition under laboratory conditions. Measured traits included plant survival, leaf number, rosette diameter, carbon assimilation rate and leaf chlorophyll content. In addition, we conducted a demographic survey of the natural populations to assess the plant's performance at the early developmental stage in the field and evaluate the ecological implications of our experimental treatments. The seedling stage contributed to the projected population growth rate in natural conditions, and the growth and survival of seedlings in the field were comparable to those grown in the control treatment. In response to high temperature, plants exhibited lower survival but produced larger rosettes with more leaves. Nitrogen deposition had little effect on plant survival and plant size; however, it increased plant survival in one population and altered the effect of temperature on the carbon assimilation rate. Populations exhibited differential plasticity indexes of measured traits in response to environmental treatments. These results suggest that even though the plants suffer from high early mortality under increasing temperature, stimulated growth at a high temperature potentially contributes to the persistence of natural populations. Natural populations might face differential extinction risks due to distinctive plastic responses to altered environments.
预计未来的环境变化将威胁山顶附近的植物种群，但与种群统计学参数相关的植物性状的可塑性反应可能会减少环境变化带来的不利影响。尽管其具有生态意义，但对于像高山植物亚种这样的物种，其可塑性的种内变异却知之甚少。在本研究中，我们在实验室条件下调查了来自四个自然种群的植物在早期发育阶段对温度和氮沉降的可塑性反应。测量的性状包括植物存活率、叶片数量、莲座直径、碳同化率和叶片叶绿素含量。此外，我们对自然种群进行了种群统计学调查，以评估该植物在野外早期发育阶段的表现，并评估我们实验处理的生态意义。在自然条件下，幼苗期对预测的种群增长率有贡献，并且野外幼苗的生长和存活情况与对照处理下生长的幼苗相当。响应高温时，植物存活率较低，但会产生更大的莲座且叶片更多。氮沉降对植物存活率和植株大小影响不大；然而，它提高了一个种群中的植物存活率，并改变了温度对碳同化率的影响。不同种群对环境处理表现出不同的可塑性指数。这些结果表明，尽管在温度升高的情况下植物早期死亡率较高，但高温下受刺激的生长可能有助于自然种群的持续存在。由于对环境变化有独特的可塑性反应，自然种群可能面临不同的灭绝风险。
