喜马拉雅-横断山冰缘带“绒毛植物”——绵参表皮毛的生态适应机制研究

喜马拉雅-横断山冰缘带拥有全球最丰富的特化植物种类，研究它们的适应机制是理解冰缘带植物多样性形成与维持的基础，但是，我们对这些植物的适应机制仍缺乏系统的理解。本项目选择高山“绒毛植物”的代表——绵参作为研究材料，以适合度为切入点，从生态学理论入手，结合多学科手段，点（几个种群的控制实验）- 面（区域尺度的种群比较）相结合，探讨特化性状——表皮毛的生态适应机制，揭示该类植物在冰缘带环境下的生存策略。重点回答的问题是：1）绵参表皮毛有什么生态功能，即受到哪些环境因素的选择？2）初步调查发现绵参表皮毛（如密度、长度和化合物）在种群间存在明显差异，那么表皮毛在区域尺度上是如何变化的？局域适应机制是什么？即：驱动表皮毛地理变异的关键因素是什么？本项目的研究结果能揭示高山冰缘带环境下“绒毛植物”的进化适应机制，丰富我们对表皮毛生态适应的理解，并为全球变化背景下预测物种性状变化与物种保护提供基础数据。

The alpine screes of the Himalaya-Hengduan Mountains harbor the richest specialized plant species in the world; studying the adaptive mechanisms of these plants to habitats of alpine screes are the basis for understanding how plant diversity forms and maintains in the harsh environments, however, the adaptive mechanisms of these plants remain largely unknown. We select Eriophyton wallichii, which has been considered as the representative of ‘woolly plants’, as the research material, to explore the adaptive significances of trichomes and uncover the evolutionarily adaptive mechanisms of these plants to alpine screes, taking the fitness as the key point and using ecological theories and multidisciplinary methods. The following specific questions are addressed: 1) What are the ecological significances of trichomes in E. wallichii ? 2) In our previous investigations the pubescence varied greatly between populations, including density, length, and chemical compounds, is there a gradient in trichomes along geographical distribution? What are the local-scaled adaptive mechanisms? i.e., what are the key factors driving the geographical variation in trichomes? Our results will help us to uncover the evolutionarily adaptive mechanism of ‘woolly plants’ to alpine screes, enrich our knowledge on evolutionary adaptions of trichomes, also provide basic data for predicting trait change and conserving species under the context of global change.