Collaborative Research: U.S.-Brazil Planning visit: Facilitating collaborative research on the Southern Brazilian Continental Shelf

合作研究：美国-巴西规划访问：促进巴西南部大陆架的合作研究

• 批准号: 1444195
• 负责人: Clifton Buck
• 金额: $ 1.04万
• 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: 2015
• 资助国家: 美国
• 起止时间: 2015-02-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1444195&HistoricalAwards=false
• 关键词: Collaborative; Research; U.S.; Brazil; Planning

The southern Brazilian continental shelf is the site of important marine fisheries, supporting economic resources for Brazil, Uruguay and Argentina. Regional population growth is expected to result in continued development of coastal areas along the shelf therefore prudent resource management requires a comprehensive assessment of present day conditions. Changes in the flux and sources of nutrients supporting the base of the regional food web could upset these economically important fisheries. Nutrients are transported into this area through outflow of the Rio de la Plata and the Patos Lagoon as well as submarine groundwater discharge but the relative contribution of nutrients and trace metals from each of these sources remains unknown. This project will support travel for three early-career U.S. investigators to establish an international collaboration with Brazilian researchers. During the visit, the U.S. research team will conduct meetings, seminars and field trips to gather regionally-relevant information. The outcome of this planning visit will be the development of an international collaborative research plan to investigate biogeochemical cycling along the southern Brazilian continental shelf. Recent evidence suggests that submarine groundwater discharge contributes a substantial amount of nutrients and trace metals (especially iron) to the coastal waters of this region but the importance of this source relative to surface outflows (e.g., Rio de la Plata plume and Patos Lagoon drainage) remains unknown. Seasonally-varying coastal currents likely disperse biogeochemically-relevant constituents differently therefore this visit will involve planning how to investigate the potential use of various water mass tracers to characterize the sources and transport mechanisms across the continental shelf. The planning work will involve developing an international collaboration to address the following questions: 1) What are the relative contributions of the Plata Plume, Patos Lagoon and submarine groundwater discharge of freshwater, nutrients and trace metals to the southern Brazilian continental shelf as determined by water mass tracers? 2) What is the seasonal effect of these sources on coastal water column dissolved and particulate trace element chemistry along the southern Brazilian continental shelf? 3) Is there a significant leachable particulate trace metal fraction available for deposition on the shelf and supply micro-nutrients during upwelling? 4) What are the characteristics of Fe-binding ligands associated with plume waters? 5) Are iron isotopic signatures useful for quantifying processes in the Plata plume system? The future proposal from this group will have results extending to larger research programs such as GEOTRACES. The planning visit will foster an international collaboration between Brazilian and U.S. researchers, and will allow a U.S. Ph.D. student to gain international experience in research project development including hypothesis formulation, objective defining and methodology verification.

巴西南部的大陆架是重要海洋渔业的所在地，为巴西，乌拉圭和阿根廷提供了经济资源。预计区域人口增长将导致沿着货架沿岸的沿海地区的持续发展，因此审慎的资源管理需要对当天条件进行全面评估。支持区域食品网络基础的养分的变化和源源不断的变化可能会使这些重要的渔业破坏。通过里约热内卢和Patos泻湖的流出以及海底地下水排放，将营养物质运输到该区域，但是从这些来源中的每个来源的养分和微量金属的相对贡献仍然未知。该项目将支持三位美国早期研究人员与巴西研究人员建立国际合作的旅行。在访问期间，美国研究团队将进行会议，研讨会和实地考察，以收集与区域相关的信息。这次计划访问的结果将是制定国际合作研究计划，以调查巴西南部大陆架沿线的生物地球化学循环。 最近的证据表明，海底地下水排放为该地区的沿海水域贡献了大量的养分和微量金属（尤其是铁），但是该来源相对于地表外流的重要性（例如，里约热内卢普拉特羽流和帕托斯泻湖排水）仍然不明。季节性变化的沿海电流可能以不同的方式分散生物地球化学的成分，因此本次访问将涉及计划如何调查各种水质示踪剂的潜在使用以表征整个大陆架的来源和运输机制。计划工作将涉及开发国际合作以解决以下问题：1）淡水，营养物质和微量金属对巴西南部大陆架子的淡水羽流，帕托斯泻湖和海底地下水的相对贡献是什么？ 2）这些源对沿海水柱的沿海水柱的季节性影响是什么？ 3）是否有可在上升流期间在架子上沉积并提供微量营养素的明显可浸出的颗粒金属分数？ 4）与羽流有关的Fe结合配体的特征是什么？ 5）铁同位素特征对量化Plata羽流系统中的过程有用吗？该小组的未来建议将延伸到较大的研究计划，例如地理位置。计划访问将促进巴西和美国研究人员之间的国际合作，并允许美国博士学位。学生在研究项目发展方面获得国际经验，包括假设制定，客观定义和方法验证。