Fan Xingke, Yan Xia, Qian Chaoju, Bachir Daoura Goudia, Yin Xiaoyue, Sun Peipei, Ma Xiao-Fei
Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Gansu Province Department of Ecology and Agriculture Research Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou China.
University of Chinese Academy of Sciences Beijing China.
Ecol Evol. 2020 Aug 19;10(18):10076-10094. doi: 10.1002/ece3.6668. eCollection 2020 Sep.
The climate in arid Central Asia (ACA) has changed rapidly in recent decades, but the ecological consequences of this are far from clear. To predict the impacts of climate change on ecosystem functioning, greater attention should be given to the relationships between leaf functional traits and environmental heterogeneity. As a dominant constructive shrub widely distributed in ACA, provided us with an ideal model to understand how leaf functional traits of desert ecosystems responded to the heterogeneous environments of ACA. Here, to determine the influences of genetic and ecological factors, we characterized species-wide variations in leaf traits among 30 wild populations of and 16 populations grown in a common garden. We found that the leaf length, width, and leaf length to width ratio (L/W) of the northern lineage were significantly larger than those of other genetic lineages, and principal component analysis based on the in situ environmental factors distinguished the northern lineage from the other lineages studied. With increasing latitude, leaf length, width, and L/W in the wild populations increased significantly. Leaf length and L/W were negatively correlated with altitude, and first increased and then decreased with increasing mean annual temperature (MAT) and mean annual precipitation (MAP). Stepwise regression analyses further indicated that leaf length variation was mainly affected by latitude. However, leaf width was uncorrelated with altitude, MAT, or MAP. The common garden trial showed that leaf width variation among the eastern populations was caused by both local adaptation and phenotypic plasticity. Our findings suggest that preferentially changes leaf length to adjust leaf size to cope with environmental change. We also reveal phenotypic evidence for ecological speciation of . These results will help us better understand and predict the consequences of climate change for desert ecosystem functioning.
近几十年来，干旱的中亚地区（ACA）气候迅速变化，但其生态后果却远未明晰。为预测气候变化对生态系统功能的影响，应更加关注叶片功能性状与环境异质性之间的关系。作为广泛分布于ACA的优势建群灌木，为我们提供了一个理想模型，以了解沙漠生态系统的叶片功能性状如何响应ACA的异质环境。在此，为确定遗传和生态因素的影响，我们对30个野生种群以及在一个共同花园中种植的16个种群的叶片性状进行了全物种变异特征分析。我们发现，北方谱系的叶片长度、宽度以及叶长宽比（L/W）显著大于其他遗传谱系，基于原位环境因素的主成分分析将北方谱系与其他研究谱系区分开来。随着纬度增加，野生种群的叶片长度、宽度和L/W显著增加。叶片长度和L/W与海拔呈负相关，随年均温度（MAT）和年降水量（MAP）增加先升高后降低。逐步回归分析进一步表明，叶片长度变异主要受纬度影响。然而，叶片宽度与海拔、MAT或MAP均无相关性。共同花园试验表明，东部种群间叶片宽度的变异是由局部适应和表型可塑性共同导致的。我们的研究结果表明，优先改变叶片长度以调整叶片大小来应对环境变化。我们还揭示了的生态物种形成的表型证据。这些结果将有助于我们更好地理解和预测气候变化对沙漠生态系统功能的影响。
