横断山高山冰缘生态系统植物繁殖特征的研究

The alpine subnival communities is the highest ecosystem in the world. Under the extremely environment selective stress, species of the communities evolved into some special adaptive mechanisms, of which the reproductive system is the crucial one. It has been being very difficulty to study the reproductive biology in alpine subnival ecosystem because the adverse circumstances, poor transport facilities, difficulty to get there, as well as very short growing season etc. Up to now it has been very poorly known or absent studies on the biological characters of the reproduction of these plants and communities. In this project, the investigations will be carried out in two aspects, one is to study the reproductive characters of the communities or ecosystem, and to reveal the reproductive, survival and adaptive mechanism of the alpine subnival plants from the level of communities; the other aspect is , by selecting some characteristic genera or groups from the subnival plants, to study the reproductive and sexual allocation along the elevation gradient, and to study the sexual system, patterns of pollination and the reproductive mechanisms of the plants which evolved into some specialized morphology in the alpine subnival ecosystem in Hengduan Mountain. Consequently to indicate the survival and adaptive mechanisms of these plants as well as the mechanisms of maintenance the stabilization of the alpine subnival ecosystem. So the investigations will have potential and important significance not only on the plant evolutionary biology and biogeography, but also on alpine plants introduction and domestication, and biodiversity protection.

高山冰缘植被是地球上海拔最高的生态系统。在极端环境的选择压力下，物种形成了特殊的适应机制，其繁殖系统特征即是其核心。由于环境恶劣、交通不便、植物生长周期短和到达困难等因素，至今为止对高山冰缘植物的繁殖生物学研究仍然非常薄弱，一些甚至是空白。该项目拟从生态系统或群落尺度上，研究其群落的繁殖生物学特征，以期从空间上揭示其生存繁殖及适应机制以及生态系统的维持机制；从具体的特征类群的尺度上，研究海拔梯度上（从低海拔到高山冰缘带）植物的繁殖分配和性分配的变化规律，开展性系统和传粉模式的研究，以及特殊结构的功能及其繁殖生物学特征的研究；从时间上探讨冰缘植物的生存机制。上述综合来揭示冰缘生态系统中物种的繁殖及生存机制。对探讨高山冰缘植物多样性起源、分布格局形成、生态适应以及生态系统稳定机制等进化生物学、生物地理学等问题具有重要的理论意义；对植物资源的引种驯化，可持续利用以及生物多样性保护也有重要的意义。

按照计划任务书项目拟从2个方面来开展研究：1）生态系统尺度：高山冰缘植物的繁殖系统特征的研究；2）物种尺度：特征类群的繁殖系统进行研究。在生态系统尺度，首次揭示了高山冰缘植物区系的繁殖系统特征，发现性系统是雌雄同体(两性)植物占主要比例(85.2% ); 果实以干果为主,比例高达99.0 %,生活型以多年生草本为主(85.8%)。对一些特征类群的研究还发现大部分植物存在传粉限制,容易造成繁殖失败, 有97.1%的两性植物是自交亲和的,它们中又有88.2%能够进行自交繁殖。在物种尺度上，探讨了海拔梯度上蓝钟花属植物种子质量沿海拔梯度的变化及对繁殖生存和种群动态的影响以及细叶蓝钟花、豹子花属繁殖系统上资源分配比例的变化以及性分配和表达式样等；弄清了洼瓣花属性系统和繁殖模式、绵参的繁殖及功能生态学的特征及繁殖生存机制以及囊距紫堇隐蔽色功能及保证繁殖生存策略等。对高山冰缘带垫状植物的功能生态学的研究发现许多垫状植物具有“肥岛效应”能为其它物种提供营养和庇护，从而提高和保证生态系统中的物种多样性并维持其繁衍生存。此外，还对高山冰缘植物的种群历史、格局形成、遗传多样性结构以及细胞地理等进行了拓展研究,取得了较好的成绩。本项目研究已完成（或超额）项目计划任务中的各项指标，发表研究论文21篇，其中SCI 11篇。包括了New Phytologist，Journal of Biogeography，Journal of Vegetation Science, Journal of Plant Ecology, Plant Ecology and Diversity, Journal of Systematics and Evolution等国际著名期刊。