Project 1: Harmful algal bloom dynamics: assessing physiological and behavioral plasticity in natural populations

项目 1：有害藻华动态：评估自然种群的生理和行为可塑性

• 批准号: 10434781
• 负责人: Donald M. Anderson
• 金额: $ 14.37万
• 依托单位: WOODS HOLE OCEANOGRAPHIC INSTITUTION
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-30 至 2024-03-08
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10434781
• 关键词: Arctic Regions; Area; Behavior; Behavioral; Cells; Chills; Climate; Complex; Cyst; Data; Detection; Development; Disease Outbreaks; Ecosystem; Environment; Event; Exposure to; Funding; Future; Gametogenesis; Germination; Goals; Growth; Habitats; Health; Human; In Situ; Individual; Investigation; Knowledge; Life Cycle Stages; Maine; Measurement; Microscope; Modeling; Needs Assessment; Nutrient; Oceans; Organism; Paralysed; Parasitic infection; Pattern; Physiological; Physiology; Phytoplankton; Poisoning; Population; Population Dynamics; Process; Proxy; Public Health; Recording of previous events; Sampling; Shellfish; Swimming; Syndrome; System; Techniques; Technology; Temperature; Time; Toxic effect; Toxin; Wood material; Work; base; behavioral plasticity; behavioral response; climate change; community engagement; conditioning; exposed human population; future climate scenario; harmful algal blooms; improved; insight; knowledge base; migration; mortality; novel; programs; response; stem

Alexandrium fundyense and Pseudo-nitzschia spp. present expanding public health threats through their associated poisoning syndromes, paralytic shellfish poisoning and amnesic shellfish poisoning. A major concern is the extent to which these harmful algal blooms (HABs) and their human health impacts will be altered by a changing climate. The Gulf of Maine is an ideal setting to explore this problem due to its long history of A. fundyense investigations examining bloom physiology, toxicity, and bloom dynamics, leading to construction of a robust population dynamics model. Nevertheless realistic forecasts under changing climate conditions remain challenging for both A. fundyense and Pseudo-nitzschia, an emerging and less studied threat. Current models for A. fundyense rely on culture-based characterizations of behavior that are not valid in the natural environment, as demonstrated by novel in situ observations made during our prior WHCOHH program. Life cycle processes, growth, grazing and mortality rates, and swimming patterns have all been found to be significantly different in situ, making culture-based data inadequate for model assessments. A second challenge stems from the adaptive potential of these taxa, whose physiologies vary substantially across their ranges. This project's scientific premise is that our ability to assess and predict short- and long- term responses of these HABs and their human health impacts to climate change requires characterization of critical rates and behavioral patterns in natural populations, generated, whenever possible, through in situ observations. Based on the new finding of a chilling requirement regulating the dormancy period of A. fundyense cysts in the Nauset Marsh estuary, Aim 1 will assess plasticity of this response across multiple habitats and populations and explore whether the temperature conditioning requirements of A. fundyense are adaptive across its range. Aim 2 will use in situ technologies to determine relationships between temperature and A. fundyense division, grazing, accumulation, and toxicity onset across a range of habitats. Previous WHCOHH work discovered unexpectedly high accumulation and division rates for A. fundyense in Nauset Marsh. If growth is similarly elevated across other habitats, incorporation of these rates into growing degree- day and more complex, mechanistic models promise improved predictions of bloom timing and toxicity and climate change assessments. Aim 3 will establish how cell concentration thresholds, parasite infections, and migration shifts contribute to A. fundyense bloom termination. Aim 4 will greatly expand the knowledge base for Pseudo-nitzschia bloom dynamics by combining previous and new in situ and lab-based observations. Pseudo-nitzschia species composition is a first order predictor of toxicity, so knowledge of species diversity and differences between species' physiology and life cycle dynamics is needed for toxicity predictions. In summary, the project will provide the in situ assessments needed to develop and refine the bloom dynamics models that underlie climate projections and estimates of human exposure to HAB toxins (Projects 2 and 3).

亚历山大藻（Alexandrium Fundyense）和伪菱形藻（Pseudo-nitzschia spp.）通过其 相关中毒综合征、麻痹性贝类中毒和遗忘性贝类中毒。一个专业 令人担忧的是这些有害藻华 (HAB) 及其人类健康影响的程度 因气候变化而改变。缅因湾因其悠久的历史而成为探索该问题的理想场所。 A.fundyense 研究水华生理学、毒性和水华动态的历史，导致 构建稳健的种群动态模型。尽管如此，气候变化下的现实预测 对于 A.fundyense 和拟菱形藻（一种新兴的、研究较少的）来说，条件仍然具有挑战性 威胁。当前的 A.fundyense 模型依赖于基于文化的行为特征，而这些特征在 自然环境，正如我们之前的 WHCOHH 期间进行的新颖的现场观察所证明的那样 程序。生命周期过程、生长、放牧和死亡率以及游泳模式都已被 发现在原位存在显着差异，使得基于文化的数据不足以用于模型评估。一个 第二个挑战源于这些类群的适应潜力，其生理学差异很大 跨越他们的范围。该项目的科学前提是我们评估和预测短期和长期的能力 这些有害生物的长期反应及其对气候变化对人类健康的影响需要表征 自然群体中的临界率和行为模式，尽可能通过现场生成 观察。基于调节 A. 休眠期的需冷量的新发现。 Nauset Marsh 河口的fundyense包囊，目标 1 将评估这种反应在多个 栖息地和种群，并探讨 A.fundyense 的温度调节要求是否 在其范围内自适应。目标 2 将使用原位技术来确定温度之间的关系 和 A.fundyense 在一系列生境中的分裂、放牧、积累和毒性发作。以前的 WHCOHH 的工作发现瑙塞特 A.fundyense 的积累率和分裂率出人意料地高 沼泽。如果其他栖息地的生长速度也同样提高，则将这些速率纳入生长程度- 日和更复杂的机械模型有望改进对开花时间和毒性的预测， 气候变化评估。目标 3 将确定细胞浓度阈值、寄生虫感染和 迁移变化导致 A.fundyense 花期终止。目标 4 将大大扩展知识库 通过结合先前和新的原位和实验室观测来研究拟菱形藻华动态。 拟菱形藻物种组成是毒性的一级预测因子，因此了解物种多样性 毒性预测需要物种生理学和生命周期动力学之间的差异。在 总之，该项目将提供开发和完善水华动态所需的现场评估 气候预测和人类接触 HAB 毒素估计的模型（项目 2 和 3）。