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，一个含有5亿加仑化肥生产厂废水的水库开始泄漏到附近的佛罗里达州坦帕湾，然后在水库看起来有灾难性故障的危险时被排进海湾。这种排水方式在两周内为海湾增加了超过一年所需的磷和氮。这些关键营养物质的快速添加对当地生态系统的影响将通过特别关注磷分子化学的变化来研究。这反过来将有助于了解生命如何适应当地环境营养负荷的快速变化。鉴于在世界各地的许多水体中，如此快速的营养物注入是一个日益严重的问题，了解对此类事件的生物反应可以反过来帮助减轻未来有问题的磷酸盐注入。该项目的大部分研究将由南佛罗里达大学的研究生进行，作为他们科学训练的一部分。将研究海湾内藻类和微生物对这种快速变化的营养负荷的生物地球化学反应。这将通过分析沿坦帕湾横截面的水和颗粒来完成，从尚未被高磷养分负荷渗透的北侧到排放发生的南侧。样品将在表层和深层采集，并将在一年的时间内采集，这是估计这种高营养负荷可能停留的时间。样品将主要通过31P NMR（核磁共振波谱）进行分析，该波谱提供了对大量P分子化学的深入分析，区分各种P分子，如无机P化合物（如正磷酸盐）、多磷酸盐（如焦磷酸盐）、有机磷酸盐单酯（如脂质磷酸盐）、有机磷酸盐二酯（如DNA）和磷酸盐（如甲基膦酸盐）。总磷采用电感耦合等离子体发射光谱法测定。快速变化的营养负荷的分子产物的时空数据将更好地理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，如正磷酸盐单酯和二酯，因此，这种排放释放的P不太可能在P被冲走时持续存在于环境中。然而，如果磷被储存在难降解的聚磷酸盐和磷酸盐中，那么这可能意味着磷的停留时间更长，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多余的磷纳入其生化分子中以进行长期储存。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。