The Alps played an important role in the biogeography of European plants and acted as a refugium for numerous species during the interglacial cycles. We investigated Nuphar pumila, one of the most emblematic glacial relicts of the Alps, by carrying out exhaustive literature and field surveys to collect relevant data on its distribution and threats. We further evaluated the level of introgression with the closely related N. lutea based on microsatellite data from natural populations across the Alps as well as from all ex situ collections and reintroductions in Switzerland. According to our results, more than 60% of the known N. pumila populations went extinct, and the species currently presents 37 natural populations in the investigated area. A large number of populations were affected by eutrophication (69%) and hybridization with N. lutea (53%). Priority should be given to the in situ conservation of genetically pure populations, while ex situ cultures should be applied to nearly extinct populations and the genetically pure individuals still present in hybrid populations. N. pumila is an excellent representative of the wetland/aquatic glacial relicts that are particularly affected by the combination of climate change and habitat degradation. International integration of research and conservation programs is needed to limit the decline of such rare species in the Alps.

中文翻译：

---

阿尔卑斯山的冰川遗迹：Nuphar pumila（睡莲科）的衰落和保护策略

阿尔卑斯山在欧洲植物的生物地理学中发挥了重要作用，并在冰川间周期中充当了许多物种的避难所。我们通过进行详尽的文献和实地调查以收集有关其分布和威胁的相关数据，对阿尔卑斯山最具标志性的冰川遗迹之一Nuphar pumila进行了调查。我们根据来自阿尔卑斯山自然种群以及瑞士所有异地采集和再引入的微卫星数据，进一步评估了与近缘黄茶的渐渗水平。根据我们的结果，超过60％的已知N. pumila种群灭绝，该物种目前在调查区域内共有37个自然种群。大量人口受到富营养化（69％）和与黄褐猪笼草的杂交（53％）的影响。应优先考虑对纯基因种群进行原地保护，而对非绝种种群应采用非原生境培养，而在杂交种群中仍存在纯遗传个体。普米拉猪笼草是湿地/水生冰川遗迹的杰出代表，尤其受到气候变化和栖息地退化的影响。为了限制这种稀有物种在阿尔卑斯山的减少，需要将研究和保护计划进行国际整合。