Collaborative Research SGER: Domoic acid toxins in the oceanic north Pacific in iron enrichment studies

合作研究 SGER：北太平洋海洋中的软骨藻酸毒素在铁富集研究中的应用

• 批准号: 0741554
• 负责人: Sibel Bargu Ates
• 金额: $ 6.15万
• 依托单位: Louisiana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2008-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0741554&HistoricalAwards=false
• 关键词: Collaborative; Research; SGER; Domoic; acid

The project addresses an emerging issue related to global warming: the necessity to reduce levels of greenhouse gases in the atmosphere. A solution proposed several decades ago is to fertilize the extensive, iron-limited, high nutrient, low chlorophyll (HNLC) regions of the sea, drawing down carbon dioxide that would otherwise exchange with the atmosphere. This solution is highly attractive due to its relatively low cost and evidence that iron fertilization does indeed promote phytoplankton blooms in such regions. Some researchers, however, have expressed alarm about the iron remedy that could result from unanticipated negative effects on the composition and functioning of ecosystems. In this project, the investigators hypothesize that iron fertilization of HNLC regions results in biomass increases of Pseudo-nitzschia that produce domoic acid (DA), a neurotoxin. The consequences of increased DA in HNLC areas could be like those observed in coastal regions, namely contamination and sometimes deaths of predators in those ecosystems. A Small Grant for Exploratory Research (SGER) is provided based on the investigators recent discovery of DA in Pseudo-nitzschia turdigula, which often blooms in iron enrichment experiments in waters of HNLC regions. The investigators developed a new toxin assay to measure DA in samples of P. turdigula collected from HNLC waters of the subarctic NW Pacific. This SGER enables the investigators to participate in an August 2007 NSF-funded research cruise measuring iron in waters of the Gulf of Alaska (GoA) along transects in HNLC (iron poor) regions and naturally enriched eddies containing terrestrially-derived iron. The investigators will measure the associated abundance and DA levels of P. turdigula along the GoA transect and in the grow-out experiments, and to determine the Pseudo-nitzschia species associated with DA production. All samples for Pseudo-nitzschia will have associated nutrient and oceanographic data to provide context for the cellular DA quotas in an oceanographic and physiological context. Results of the research are important in determining ecosystem effects iron enrichment.

该项目解决了与全球变暖有关的新兴问题：减少大气中温室气体水平的必要性。几十年前提出的一种解决方案是为海洋的广泛，铁限制，高营养，低营养，低营养叶绿素（HNLC）区域施肥，降低二氧化碳，否则将与大气交换。由于其成本相对较低，而且证据表明铁施肥确实确实促进了此类地区的浮游植物开花，因此该解决方案具有很高的吸引力。然而，一些研究人员对铁疗法表示了警报，这可能是由于对生态系统组成和功能的意外负面影响可能造成的。在该项目中，研究人员假设HNLC区域的铁受精会导致伪nitzschia的生物量增加，从而产生神经毒素（DA），一种神经毒素。 HNLC地区DA增加的后果可能就像在沿海地区观察到的那样，即污染，有时甚至是这些生态系统中的捕食者死亡。基于研究人员在伪尼兹奇亚（Pseudo-Nitzschia turdigula）中发现DA的最新发现提供了探索性研究（SGER）的少量赠款，该发现通常在HNLC地区的水域富集实验中开花。 研究人员开发了一种新的毒素测定法，以测量从北极西北部HNLC水域收集的毛tig虫样品中的DA。 该SGER使研究人员能够参加2007年8月NSF资助的研究巡航，测量了阿拉斯加湾（GOA）（果阿）沿HNLC（Iron Door）区域（Iron Door）区域的铁和天然富含地面衍生的铁的铁的铁。 研究人员将测量果阿果区沿果阿果果的相关丰度和DA水平，并在长大的实验中，并确定与DA生产有关的伪nitzschia物种。所有用于伪nitzschia的样本都将具有相关的营养和海洋数据，以在海洋学和生理环境中为细胞DA配额提供背景。 研究结果对于确定生态系统影响铁的富集很重要。