Do fine-scale water column structure and particle aggregations favor gelatinous-dominated food webs in subtropical continental shelf environments?

细尺度水柱结构和颗粒聚集是否有利于亚热带大陆架环境中以凝胶状为主的食物网？

• 批准号: 2244690
• 负责人: Adam Greer
• 金额: $ 144.48万
• 依托单位: University of Georgia Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-01-01 至 2026-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2244690&HistoricalAwards=false
• 关键词: Do; fine; scale; water; column; Do; fine; scale; water; column

Using new ocean observing technologies in two contrasting locations, this research is combining measurements of biological and environmental conditions to understand highly productive ocean shelf food webs. Within marine food webs, a diverse community of small animals, referred to collectively as zooplankton, serve as prey for larger animals including fishes and marine mammals. Zooplankton can also influence lower trophic levels, such as marine microbes that in turn, affect nutrient and gas cycling throughout the oceans. This project is also supporting graduate and undergraduate students, including several from Savannah State University, a Historically Black University with undergraduate and graduate programs in marine sciences. The field research is providing authentic oceanographic experiences for K-12 educators, who will participate in the planned research cruises, as well as research opportunities for juniors and seniors at a local high school with high enrollment of groups underrepresented STEM. Public outreach includes annual open house events at the University of Georgia’s Skidaway Institute of Oceanography.This project addresses fundamental questions in ocean sciences regarding how environmental conditions affect the structure and composition of zooplankton communities in continental shelf ecosystems. Biologically productive shelf ecosystems can oscillate between extremes of vertically mixed waters during windy and colder seasons and vertically stratified waters during warmer and calmer conditions. Warm, calm conditions favor the formation of dense layers or aggregations of plankton and particulate material, generating hot spots of biological activity that potentially allow marine organisms to feed at much higher rates than water-column-average abundances might suggest. Although physical mechanisms of layer formation and plankton groups associated with them have been described in several shelf environments, less is known about the influence of layers on zooplankton community composition and trophic transfer. For fast-reproducing pelagic tunicates such as salps, pyrosomes, appendicularians, and doliolids, these layers or aggregations may serve as rich food resources that prime pelagic tunicates to form dense blooms which then ultimately serve as food for gelatinous predators. This sequence of events, from layer formation to pelagic tunicate reproduction and predation on the bloom, may generate high abundances of gelatinous organisms throughout the marine food web. The investigators will test this hypothesis by measuring fine-scale abundances of gelatinous zooplankton with in-situ imaging, gelantinous zooplankton diets using molecular gut content analysis, and food web properties using compound-specific stable isotopes in both vertically mixed and stratified conditions. To determine if food web interactions are generalizable to water columns with and without vertical structure, these processes will be compared in the South Atlantic Bight and northern Gulf of Mexico shelf ecosystems. Both provide favorable conditions for doliolid blooms yet differ in drivers of vertical stratification. This project is co-funded by the Directorate for Geosciences to support AI/ML advancement in the geosciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

这项研究使用新的海洋观测技术在两个对比的位置，将生物学和环境条件的测量结果结合在一起，以了解高生产力的海滩食品网。在海洋食品网中，一个由小动物的潜水员社区共同称为浮游动物，是较大动物在内的猎物，包括鱼类和海洋哺乳动物。浮游动物也会影响较低的营养水平，例如海洋微生物，而海洋微生物又影响了整个海洋的营养和气体循环。该项目还支持毕业生和本科生，其中包括萨凡纳州立大学的几位，这是一所历史悠久的黑人大学，在海洋科学领域拥有本科生和研究生课程。现场研究正在为K-12教育者提供真实的海洋学经验，他们将参加计划中的研究巡游，并为当地一所当地高中的大三和老年人提供研究机会，其中有代表性不足的STEM。公共宣传包括佐治亚大学Skidaway海洋学研究所的年度开放日活动。该项目涉及有关环境条件如何影响连续货架生态系统中浮游动物社区的结构和组成的海洋科学基本问题。生物生产的货架生态系统可以在较冷和较冷的季节中垂直混合水以及在温暖和平静的条件下垂直分层的水之间旋转。温暖，平静的条件有利于形成浮游生物和特定材料的密集层或聚集的形成，从而产生了生物活性的热点，这些热点可能使海洋生物以比水柱平均水平的丰度更高的速度喂食。尽管已经在几个架子环境中描述了层形成和浮游生物组的物理机制，但对层对浮游动物社区组成和营养转移的影响知之甚少。对于快速产生的上层外膜，例如萨奶油，鸣粒，阑尾式和多醇剂，这些层或聚集可能是丰富的食物资源，这些食物是质体膜的丰富食物，以形成致密的血液，最终充当凝胶状掠食者的食物。从层的形成到上层剪裁的繁殖和盛开的制剂，这一事件可能会在整个海洋食品网中产生大量的凝胶生物。研究人员将通过使用分子肠道含量分析的原位成像，凝胶状浮游饮食来测量胶状浮游动物的精细量表，并使用复合特异性稳定的同位素在垂直混合和分层条件下测量胶状浮游生物。为了确定食物网的相互作用是否可以推广到具有和没有垂直结构的水柱，将在墨西哥货架生态系统的南大西洋野合和北部海湾进行比较。两者都为垂直分层的驱动因素提供了有利的条件，却有所不同。该项目由地球科学局共同资助，以支持地球科学中的AI/ML进步。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的评估审查标准来通过评估来支持的。