Collaborative Research: Ecological and biogeochemical role of Rhizaria in the oligotrophic ocean

合作研究：贫营养海洋中根茎的生态和生物地球化学作用

• 批准号: 2227766
• 负责人: Leocadio Blanco-Bercial
• 金额: $ 45.62万
• 依托单位: Bermuda Institute of Ocean Sciences (BIOS), Inc.
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-15 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2227766&HistoricalAwards=false
• 关键词: Collaborative; Research; Ecological; biogeochemical; role

Rhizaria are large, single-celled organisms that contribute to chemical cycles in the world’s oceans. Common Rhizaria (e.g. Acantharea, Foraminifera, Polycystines, Phaeodarea) form mineral shells that are part of the ocean’s strontium, silica, and carbon budgets, and they represent at least 5.2% of the oceanic biological carbon reservoir in the surface zone. Better understanding of groups of Rhizaria that are present, their biomass, and how their populations change across different ocean depths is essential to model oceanic nutrient cycles, but this information is poorly resolved or lacking for large Rhizaria in one of the largest biomes on Earth, the central, low-nutrient ocean gyres. This collaborative project involves a team of early career and more established investigators, provides measurements needed to develop a model of Rhizaria contribution to sinking nutrients in the deep ocean, and is adding to our understanding of how nutrients move in the oceans and how changing environmental conditions affect those cycles. It is generating large datasets that can be used by oceanographic researchers and is delivering oceanographic, biological, and data-science themed experiential learning opportunities for undergraduate, graduate, and high school students.This study provides 1) greatly improved estimates of total Rhizaria biomass in the oligotrophic ocean, 2) novel measurements of vertical distribution and environmental niche characteristics of Rhizaria, 3) measurements of seasonal variation in Rhizaria biomass and community composition, 4) identification of the environmental drivers of seasonal and spatial variation in Rhizaria populations, and 5) a model-based estimate of the contributions of Rhizaria to vertical flux into the deep ocean. The investigators are using a combination of Niskin bottle sampling, particle gel traps, net tows, and cutting-edge in situ imaging (using an Underwater Vision Profiler, UVP5-DEEP) of Rhizaria to bypass limitations in other sampling methods to produce accurate estimates of Rhizaria biomass. Sampling occurs across a wide depth range (0-1200 m), at monthly intervals, and in conjunction with a wide array of other oceanographic measurements collected as part of the Bermuda Atlantic Time-series Study (BATS). UVP imagery data is integrated with molecular identification of Rhizaria using community metabarcoding, ZooSCAN imaging, and barcoding of individual Rhizaria collected from net tows and gel traps taken in conjunction with UVP casts. The investigators are using size-specific elemental analyses of Rhizaria and seasonally and vertically explicit estimates of Rhizaria biomass to model Rhizaria contributions to vertical flux. Along with data collected by the Bermuda Atlantic Time Series and Ocean Flux Program, new data on Rhizaria are being incorporated into a model of carbon and nutrient transfer into the deep ocean. The model estimates three ways that Rhizaria likely impact the carbon cycle -- by feeding on particle flux, by contributing ballast to marine snow, and by sinking directly -- and shows how these might vary across space and time. This project is jointly funded by the Biological Oceanography, Chemical Oceanography, and Established Program to Stimulate Competitive Research (EPSCoR) Programs.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.

根瘤菌是大型的单细胞生物，有助于世界海洋中的化学周期。共同的根瘤菌（例如，acantharea，有孔虫，多囊，phaeodarea）形成矿物壳，是海洋锶，二氧化硅和碳预算的一部分，它们占表面区域中海洋生物学碳储层的至少5.2％。更好地了解存在的根瘤菌，它们的生物量以及它们的种群在不同的海洋深度上的变化对于建模海洋养分周期至关重要，但是在地球上最大的，中央，低稳态的海洋gyres中，该信息的解决方案很差或缺乏大型根瘤菌。这个协作项目涉及一支早期职业和更知名的研究人员，提供了为开发深海中养分的贡献所需的测量，并加深了我们对养分如何在海洋中移动以及环境状况如何影响这些循环的理解。它正在生成大型数据集，可以由海洋学研究人员使用，并为本科生，毕业生和高中生提供海洋学，生物学和数据科学主题的专家学习机会。这项研究提供了1）大大改善了对寡头营养的总含量和环境分布的新颖特征的新型含量的RHIZERIAMITAL RHIZER ARNIZ ARNICAR NICHER的新型变化的估计值。 Rhizaria生物量和社区组成，4）鉴定Rhizaria种群中季节性和空间变化的环境驱动因素，以及5）基于模型的Rhizaria对垂直通量进入深海的贡献的模型估计。研究人员正在使用Niskin瓶装采样，颗粒凝胶陷阱，净折纸和尖端原位成像（使用Rhizaria的水下视觉探测器，UVP5-Deep）的尖端成像，以绕过其他采样方法中的限制，以产生Rhizaria Biomass的准确估计。采样发生在宽深（0-1200 m）的范围内，每月间隔以及作为百慕大大西洋时间序列研究（BAT）的一部分收集的其他大量海洋学测量结果。 UVP成像数据与使用社区元编码，ZOOSCAN成像以及从净滚水和凝胶陷阱和UVP铸件结合使用的凝胶陷阱收集的单个根瘤菌的条形码和条形码。研究人员正在使用根瘤菌的大小特异性元素分析，以及季节性和垂直明确的rhizaria生物量估计值，以模拟对垂直通量的根瘤菌的贡献。除了百慕大大西洋时间序列和海洋通量计划所收集的数据外，有关根瘤菌的新数据也被纳入碳和营养转移到深海的模型中。该模型估算了浮雕可能影响碳循环的三种方式 - 通过以粒子通量，养育镇压为海洋雪以及直接下沉来影响碳循环 - 并显示它们在时间和时间之间如何变化。该项目由生物海洋学，化学海洋学和启发竞争性研究计划（EPSCOR）计划的既定计划共同资助。该奖项反映了NSF的法定任务，并通过评估基金会的智力优点和更广泛的影响审查标准，通过评估来诚实地支持。