Urat Desert-grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Lanzhou, 730000, Gansu Province, China.
BMC Plant Biol. 2024 May 9;24(1):371. doi: 10.1186/s12870-024-05080-x.
Variations in functional traits serve as measures of plants' ability to adapt to environment. Exploring the patterns of functional traits of desert plants along elevational gradients is helpful to understand the responses and adaptation strategies of species to changing environments. However, it is unknown whether the relationship between functional traits and elevation is affected by differences in the species' elevational distributions (elevation preference and species' range). Importantly, most researches have concerned with differences in mean trait values and ignored intraspecific trait variation. Here, we measured functional traits of desert plants along a wide elevational gradient in the Tibetan Plateau and adjacent areas and explored functional trait patterns over elevation in species with different elevational distributions. We decomposed trait variation and further investigated characterizations of intraspecific variation. Ultimately, the main drivers of trait variation were identified using redundancy analysis. We found that species' elevational distributions significantly influenced the relationship of functional traits such as plant height, leaf dry matter content, leaf thickness, leaf nitrogen and carbon content with elevation. Species with a lower elevational preference showed greater trait variation than species with a higher elevational preference, suggesting that species that prefer high elevation are more conservative facing environmental changes. We provide evidence that interspecific trait variation in leaf thickness and leaf carbon content decreased with increasing species' range, indicating that increased variations in resistance traits within species make greater responsiveness to environmental changes, enabling species a wider range. Elevation, temperature and precipitation were the main drivers of trait variation in species with a low elevational preference, while the effect of precipitation on trait variation in species with a high elevational preference was not significant. This study sheds new insights on how plants with different elevational distributions regulate their ecological strategies to cope with changing environments.
功能性状的变化可作为植物适应环境能力的衡量标准。探索荒漠植物沿海拔梯度的功能性状模式有助于了解物种对环境变化的响应和适应策略。然而，目前尚不清楚功能性状与海拔之间的关系是否受到物种海拔分布（海拔偏好和物种范围）差异的影响。重要的是，大多数研究都关注于平均性状值的差异，而忽略了种内性状变异。在这里，我们沿着青藏高原及其周边地区的一个宽海拔梯度测量了荒漠植物的功能性状，并探讨了具有不同海拔分布的物种在海拔上的功能性状模式。我们对性状变异进行了分解，并进一步研究了种内变异的特征。最终，使用冗余分析确定了性状变异的主要驱动因素。我们发现，物种的海拔分布显著影响了植物高度、叶干物质含量、叶厚度、叶氮和碳含量等功能性状与海拔的关系。海拔偏好较低的物种表现出更大的性状变异，而海拔偏好较高的物种则表现出较小的性状变异，这表明偏好高海拔的物种在面对环境变化时更为保守。我们提供的证据表明，叶片厚度和叶片碳含量的种间性状变异随着物种范围的增加而减少，这表明种内抗性性状的变异增加，对环境变化的响应更大，从而使物种的分布范围更广。海拔、温度和降水是低海拔偏好物种性状变异的主要驱动因素，而降水对高海拔偏好物种性状变异的影响不显著。这项研究为不同海拔分布的植物如何调节生态策略以应对环境变化提供了新的见解。
