Dimensions: Collaborative Research: Functional diversity of chemosymbiosis in lucinid bivalves from coastal biomes

所有已知的文蛤家族都含有化学共生菌，这种细菌可以固定碳，并在没有阳光的情况下将其提供给宿主。由于绿藻在浅海沉积物中非常丰富，它们对孔隙水组成、营养物质悬浮、沉积物生物地球化学和植被生产力的影响是相当大的。然而，它们在沉积物氮和甲烷循环中的作用尚不清楚，特别是与深海环境中的其他化学共生系统相比。此外，目前尚不清楚荧光虫种群和/或功能多样性的下降可能如何影响沿海生物群和生态系统服务，甚至不清楚是什么因素可能导致荧光虫种群总体下降。该项目将调查从原始到高度改变的浅海环境中未被开发的荧光素化学共生生物的遗传、分类和功能多样性。抽样将在佛罗里达州、加利福尼亚州和巴哈马群岛进行。研究人员还将测试表征过去地质历史中亮细菌生物多样性的方法。这项研究有望填补我们对荧光素化学共生系统的理解的空白，包括在不断变化的生态系统条件下，特别是由于人为影响，如何改变荧光素及其内共生体的基因表达。这项研究将填补在对自然和人为干扰敏感的生境中可能发生的荧光素生物多样性丧失的一个重大空白，并将对沿海资源管理决策具有重要意义。研究人员将为研究生和本科生提供地球化学、微生物学和古生物学方面的跨学科培训，包括在巴哈马的实地考察、博物馆收藏标准培训、实验室研究和计算生物信息学。来自代表性不足的STEM群体的学生将参与该项目，参与大学外展和指导计划将通过正式和非正式的课堂、公开演讲机会和博物馆活动，瞄准共生和生物多样性主题。

All known clams of the Lucinidae family harbor chemosymbiotic bacteria that fix carbon and supply it to their hosts in the absence of sunlight. Because lucinids are very abundant in shallow marine sediments, their effects on porewater composition, nutrient suspension, sediment biogeochemistry and vegetation productivity are considerable. However, their roles in sediment N and methane cycling are unknown, especially compared to other chemosymbiotic systems in deep-marine settings. Moreover, it is unclear how a decline in lucinid populations and/or functional diversity may impact coastal biome and ecosystem services, or even what could lead to lucinid population declines overall. This project will investigate the underexplored genetic, taxonomic, and functional diversity of lucinid chemosymbioses in shallow marine environments ranging from pristine to highly altered. Sampling will take place in Florida, California, and The Bahamas. The investigators will also test for ways to characterize lucinid-bacteria biodiversity in the geologic past. This research is expected to fill gaps in our understanding of lucinid chemosymbiotic systems, including how gene expression is altered for lucinids and their endosymbionts in changing ecosystem conditions, particularly due to anthropogenic impact.This research will fill a major gap in understanding lucinid biodiversity loss that may occur in habitats sensitive to natural and anthropogenic disturbances and will be important for coastal resource management decisions. The researchers will provide interdisciplinary training in geochemistry, microbiology, and paleobiology to graduate and undergraduate students, including field studies in The Bahamas, training in museum collection standards, laboratory research, and computational bioinformatics. Students from underrepresented STEM groups will be involved on the project, and involvement with university outreach and mentoring programs will target symbiosis and biodiversity topics through formal and informal classroom, public speaking opportunities, and museum activities.