DISSERTATION RESEARCH: The effects of climate-driven phenological shifts on plant-pollinator interactions and reproductive success

大多数开花植物的繁殖，包括三分之一的农作物，都是通过蜜蜂授粉来辅助的。随着蜜蜂数量的持续下降，美国本土的近4000种蜜蜂可能会成为更重要的作物传粉者。随着气候持续变暖，人们担心植物和蜜蜂物种正在不平等地改变它们活动的时间，导致活动时间的不匹配。如果植物在蜜蜂不活跃的时候开花，繁殖就会失败。该项目将研究重要活动时间的变化如何影响植物和蜜蜂的相互作用，以及对植物繁殖的影响。研究结果将有助于了解气候变化如何影响野生植物和作物的繁殖，并对生物多样性和全球粮食生产产生影响。通过支持博士生的教育和培训以及来自代表性不足群体的本科生的参与，将加强科学工作队伍。气候变暖已经改变了共同进化的植物和传粉者物种之间物候重叠的数量。利用蒙大拿州原生的有叶蜂和独居蜂，在封闭的生态系统中控制有叶蜂的群落组成。蜜蜂的出现和植物的开花时间将通过战略性越冬和温室管理来控制。开花的植物和新兴的蜜蜂将被分配到网格边的中生态系统，根据物候学的析因设计。物候重叠变化对蚁蜂相互作用模式和蚁蜂繁殖成功的影响将通过在每个中胚层进行蜜蜂访视观察和确定每个植物物种产生的种子数量和质量来评估。这项研究产生的经验证据将有助于查明最容易受到气候变化负面影响的植物和传粉媒介物种，并为保护行动提供信息。

Reproduction in most flowering plants, including one-third of crops, is aided through pollination by bees. The nearly 4000 species of bees native to the USA may become more important pollinators of crops as honey bee populations continue to decline. As climate-warming continues, there is concern that plant and bee species are shifting the timing of their activities unequally, causing a mismatch in the time of activity. If plants flower when bees are not active, reproduction could fail. This project will investigate how shifts in the timing of important activities will affect how plants and bees interact, and the consequences for plant reproduction. Results will help to understand how climate change will affect wild plant and crop reproduction, with implications for biodiversity and global food production. The scientific workforce will be strengthened through support for the education and training of a doctoral student and participation of an undergraduate from an underrepresented group. Climate-warming has altered the amount of phenological overlap between coevolved plant and pollinator species. Using forb and solitary bee species native to Montana, forb-bee community composition will be manipulated within enclosed mesocosms. Bee emergence and plant blooming times will be controlled by strategic overwintering and greenhouse management. Blooming forbs and emerging bees will be assigned to mesh-sided mesocosms following a factorial design based on phenologies. The effects of altered phenological overlap on forb-bee interaction patterns and forb reproductive success will be assessed by conducting bee visitation observations at each mesocosm and determining the number and mass of seeds produced for each plant species. Empirical evidence generated by this study will help pinpoint plant and pollinator species most vulnerable to the negative effects of climate change, as well as inform conservation actions.