Collaborative Research: The effects of diatom-produced polyunsaturated aldehydes on the microbial food wed in temperate and polar waters

合作研究：硅藻产生的多不饱和醛对温带和极地水域微生物食物的影响

• 批准号: 1357169
• 负责人: James Pierson
• 金额: $ 47.73万
• 依托单位: University of Maryland Center for Environmental Sciences
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-01 至 2019-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1357169&HistoricalAwards=false
• 关键词: Collaborative; Research; effects; diatom; produced

Overview: This project will conduct a set of field/laboratory experiments to address the following hypotheses with respect to microzooplankton (consumers between 20-200 µm) and diatom- produced polyunsaturated aldehydes: I. Aldehydes will impair microzooplankton herbivory on diatoms and non-diatom phytoplankton. II. Aldehydes will reduce the growth rates of microzooplankton and non PUA-producing phytoplankton. III. In the presence of aldehyde-producing diatoms, copepods will switch to microzooplankton, whereas non- (mildly)- toxic diatoms will be an important food source for copepods. IV. The effects of aldehydes on microzooplankton and copepods will depend on the grazers' prior exposure to PUA. The experiments will include natural plankton, captured copepods, cultured Skeletonema marinoi (SM), including its aldehyde-producing strain, and synthetic aldehydes. To gain insights into complex interactions within planktonic communities, detailed information on their composition, abundance, and dynamics will be obtained using microscopy, flow-cytometry, and cytological methods. This approach will allow the PIs to draw conclusions about the role of diatom-produced aldehydes in phytoplankton-microzooplankton- copepod trophic interactions. The PIs will coordinate efforts and exchange information with the PUA study group at the Stazione Zoologica Anton Dohrn (Naples, Italy).Intellectual merit: Diatoms are dominant autotrophic plankton in the ocean. Recent evidence indicates that microzooplankton are the dominant herbivores, whereas copepods often rely on microzooplankton as food, except during peak diatom production. The ability of microzooplankton to feed on large diatoms and grow as fast as their algal prey leads to the question of what allows diatoms to escape microzooplankton grazing control during the initial phases of their blooms and maintain the blooms until nutrient resources are depleted? Allelopathy is wide spread among phytoplankton. The cosmopolitan bloom-forming SM produces several aldehydes and has become a model organism in plankton allelopathy studies. Most studies on diatom cytotoxicity have been dedicated to inhibitory effects on reproduction and development of marine invertebrates, whereas surprisingly little information exists on its impact on key diatom grazers, microzooplankton. Preliminary results in the Chesapeake Bay show that aldehydes may induce cascading effects within planktonic communities. The proposed study will: (1) Improve our knowledge of the critical diatom-microzooplankton-copepod links in the coastal ocean; (2) Generate novel data on the effects of allelopathy on marine food webs; (3) Contribute to our understanding of broader patterns of marine ecosystems by comparing plankton structure and dynamics in the temperate Atlantic waters; (4) Advance biological oceanography through international collaboration.Broader Impacts: One post-doctoral fellow, two graduate students and several undergraduate students at the Universities of Akron and Maryland will be trained as a result of this project. The project will attract motivated minority students into the program. The research will be extended to students in grades 7-12 and teachers via an interactive distance learning series in collaboration with the WVIZ Ideastream network. The PIs will continue an existing outreach partnership with the Great Lakes Science Center, where a recent electronic presentation dedicated to Arctic change and NSF-sponsored research was seen by ca. 45,000 visitors. The PIs will also work with the Cleveland Museum of Natural History to develop public programs, and with the National Inventors Hall of Fame STEM Middle School to develop a curriculum focused on polar research. Curriculum modules will be available as free downloads from a dedicated website. Broader Impacts, LLC, will evaluate these education and outreach activities.

概述：该项目将进行一系列现场/实验室实验，以解决以下关于微Zooplankton（20-200 µm之间的消费者）和硅藻产生的多不饱和醛的假设：I。醛将损害Microzooplankton Herbivory on Diatoms on Diatom and diatom phytomphytopoplankton。 ii。醛将降低Microzooplankton和非生产PUA的浮游植物的生长速度。 iii。在存在醛的硅藻的情况下，copepods将切换到Microzooplankton，而非（轻度） - 毒性硅藻将是copepods的重要食物来源。 iv。醛对Microzooplankton和Copepods的影响将取决于放牧者的事先暴露于PUA。这些实验将包括天然浮游生物，捕获的copepods，培养的骨骼马诺伊（SM），包括其醛产生菌株和合成醛。为了洞悉浮游群落中复杂的相互作用，将使用显微镜，流程仪和细胞学方法获得有关其组成，抽象和动态的详细信息。这种方法将使PI得出关于硅藻产生的醛在浮游植物 - 麦克罗龙普兰克顿 - pepod-cepopod营养相互作用中的作用的结论。 PIS将与Stazione Zoologica Anton Dohrn（意大利那不勒斯）的PUA研究组协调努力和交换信息。IntlectualFure：硅藻是海洋中主要的自身营养浮游生物。最近的证据表明，Microzooplankton是主要的草食动物，而Copepods通常依靠Microzooplankton作为食物，除非在硅藻峰值生产期间。 Microzooplankton以大硅藻为食并与藻类捕食一样快地生长的能力导致了一个问题是，在其血液的初始阶段，硅藻可以逃避microzooplankton放牧控制，并保持血液并保持血液直到营养资源枯竭？转运性病在浮游植物中广泛传播。大都会形成的SM产生了几种醛，并已成为浮游生物病变研究中的模型生物。大多数关于硅藻细胞毒性的研究都致力于抑制对海洋无脊椎动物的繁殖和发展的抑制作用，而关于其对关键硅藻颗粒剂Microzooplankton的影响的信息很少。切萨皮克湾的初步结果表明，醛可能会在浮游生物社区内引起级联效应。拟议的研究将：（1）提高我们对沿海海洋中关键的硅藻 - 微龙 - pepepod链路的了解； （2）生成有关树种病毒对海洋食物网的影响的新颖数据； （3）通过比较温度大西洋水域中的浮游生物结构和动力学来有助于我们对海洋生态系统的更广泛模式的理解； （4）通过国际合作提前生物海洋学。Broader的影响：一名博士后研究员，两名研究生和阿克伦大学和马里兰州大学的几名本科生将受到该项目的培训。该项目将吸引有积极进取的少数民族学生参加该计划。这项研究将通过与WVIZ IDEATTREAM网络合作，通过互动远距离学习系列扩展到7 - 12年级的学生和教师。 PI将继续与大湖科学中心建立现有的外展合作伙伴关系，该中心最近的电子演示文稿致力于北极变化和NSF赞助的研究。 45,000名游客。 PIS还将与克利夫兰自然历史博物馆合作开发公共计划，并与国家发明家名人堂STEM中学一起开发着针对极地研究的课程。课程模块将作为专用网站免费下载提供。更广泛的影响力有限责任公司将评估这些教育和外展活动。