RAPID: Phosphorus Molecular Biogeochemistry during a Rapidly Changing Nutrient Load in Tampa Bay, FL

RAPID：佛罗里达州坦帕湾营养负荷快速变化期间的磷分子生物地球化学

• 批准号: 2131222
• 负责人: Matthew Pasek
• 金额: $ 7.15万
• 依托单位: University of South Florida
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-06-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2131222&HistoricalAwards=false
• 关键词: RAPID; Phosphorus; Molecular; Biogeochemistry; during

In late March 2021, a reservoir containing 500 million gallons of wastewater from a fertilizer production plant began leaking into nearby Tampa Bay, Florida, and then was drained into the bay when the reservoir looked to be in danger of catastrophic failure. This drainage added over a year’s worth of phosphorus (P) and nitrogen to the bay in a two-week period. The effects of this rapid addition of these critical nutrients on the local ecosystem will be investigated by specifically focusing on changes to the molecular chemistry of phosphorus. This in turn will help understand how life adapts to rapid changes to the local environmental nutrient load. Given that such rapid infusions of nutrients are a growing problem in many water bodies throughout the world, understanding the biological response to such events could in turn help mitigate future problematic phosphate infusions. Much of the research for this project will be conducted by graduate students at the University of South Florida as part of their scientific training.The biogeochemical response of algae and microorganisms within the bay to this rapid change in nutrient load will be investigated. This will be accomplished by analyzing water and particulates along a cross section of Tampa Bay, from the north side that has yet to be infiltrated by a high P nutrient load, to the south where the discharge occurred. Samples will be taken both at the surface and at depth, and will be taken over the course of one year, which is estimated as a possible residence time of this high nutrient load. Samples will be analyzed primarily by 31P NMR (nuclear magnetic resonance spectroscopy), which provides an in-depth analysis of the bulk molecular P chemistry, distinguishing between various P molecules such as inorganic P compounds (e.g., orthophosphate), polyphosphates (e.g., pyrophosphate), organophosphate monoesters (e.g., lipid phosphates), organophosphate diesters (e.g., DNA), and phosphonates (e.g., methylphosphonate). Total phosphorus will be determined by ICP-OES (inductively coupled plasma-optical emission spectrometry). Spatial and temporal data on the molecular products of a rapidly changing nutrient load will provide a better understanding of how organisms adapt to this changing system. For instance, rapid growth may simply result in more biomolecules such as orthophosphate monoesters and diesters being produced, and as such, the P released by this discharge is unlikely to persist in the environment as P flushes out. However, if the phosphorus is instead stored within refractory polyphosphates and phosphonates, then this may implicate a longer P residence time, as these molecules indicate a longer-term storage of P by microorganisms. The overarching goal will be to better constrain how microbes incorporate excess phosphorus into their biochemical molecules for long-term storage.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.

2021 年 3 月下旬，一座化肥生产厂含有 5 亿加仑废水的水库开始泄漏到佛罗里达州坦帕湾附近，然后在水库看起来面临灾难性溃决的危险时被排入海湾。 这种排水在两周内向海湾添加了一年多的磷 (P) 和氮。 将通过特别关注磷分子化学的变化来研究这些关键营养素的快速添加对当地生态系统的影响。这反过来将有助于了解生命如何适应当地环境养分负荷的快速变化。 鉴于如此快速的营养物质注入是世界各地许多水体中一个日益严重的问题，了解对此类事件的生物反应反过来可能有助于缓解未来存在的磷酸盐注入问题。 该项目的大部分研究将由南佛罗里达大学的研究生进行，作为其科学培训的一部分。将研究海湾内藻类和微生物对营养负荷快速变化的生物地球化学反应。 这将通过分析坦帕湾横截面的水和颗粒物来完成，从尚未被高磷营养物负荷渗透的北侧到发生排放的南侧。 样品将在地表和深处采集，采集时间为一年，估计为这种高营养负荷的可能停留时间。 样品将主要通过 31P NMR（核磁共振波谱）进行分析，它可以对大分子磷化学进行深入分析，区分各种磷分子，例如无机磷化合物（例如正磷酸盐）、多磷酸盐（例如焦磷酸盐）、有机磷酸单酯（例如脂质磷酸盐）、有机磷酸盐 二酯（例如DNA）和膦酸酯（例如甲基膦酸酯）。 总磷将通过 ICP-OES（电感耦合等离子体光发射光谱法）测定。 关于快速变化的营养负荷的分子产物的空间和时间数据将有助于更好地了解生物体如何适应这种变化的系统。 例如，快速生长可能只是导致产生更多的生物分子，例如正磷酸单酯和二酯，因此，当磷冲走时，这种排放释放的磷不太可能持续存在于环境中。 然而，如果磷储存在难熔的聚磷酸盐和膦酸盐中，则这可能意味着更长的磷停留时间，因为这些分子表明微生物对磷的储存时间更长。 总体目标将是更好地限制微生物如何将过量的磷纳入其生化分子中以进行长期储存。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。