Collaborative Research: Oceanic diazotroph community structure and activities in a high carbon dioxide world

合作研究：高二氧化碳世界中的海洋固氮菌群落结构和活动

• 批准号: 0850827
• 负责人: Matthew Church
• 金额: $ 43.79万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-15 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0850827&HistoricalAwards=false
• 关键词: Collaborative; Research; Oceanic; diazotroph; community

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."The North Pacific Subtropical Gyre (NPSG) is the largest ocean ecosystem on Earth, playing a prominent role in global carbon cycling and forming an important reservoir of marine biodiversity. Nitrogen (N2) fixing bacteria (termed diazotrophs) provide a major source of new nitrogen to the oligotrophic waters of the NPSG, thereby exerting direct control on the carbon cycle. Oceanic uptake of CO2 causes long-term changes in the partial pressure of CO2 (pCO2) in the seawater of this ecosystem. Therefore, understanding how carbon system perturbations may influence ocean biogeochemistry is an important and timely undertaking.In this project, the investigators will examine how natural assemblages of N2 fixing microorganisms respond to perturbations in seawater carbon chemistry. Laboratory and field-based experiments will be placed in the context of monthly time series measurements on the activities and abundances of N2 fixing microorganism abundances. Together, the project will provide insight into the dependence of N2 fixing microorganism physiology on variations in CO2. The broad objectives of the research are: (1) Quantify the responses and consequences of changes in seawater pCO2 on the growth and community structure of naturally-occurring assemblages of ocean diazotrophs; (2) Identify why and how changes in seawater pCO2 influence the growth and carbon acquisition strategies of two model marine diazotrophs (Trichodesmium and Crocosphaera); and (3) Quantify temporal variability in diazotroph community structure and activities at Station ALOHA. The broader impacts include providing important insights into potential influences of climate change scenarios on ocean biogeochemistry which will be valuable to microbial ecologists, climate change scientists, and biogeochemists. In addition, research opportunities for both undergraduate and graduate students are planned with an emphasis on participation of women and underrepresented groups in science.

“该奖项是根据2009年的《美国复苏与再投资法》（公法111-5）资助的。”北太平洋亚热带GYRE（NPSG）是地球上最大的海洋生态系统，在全球碳循环和形成一个重要作用海洋生物多样性的重要水库。氮（N2）固定细菌（称为重18zotrophs）为NPSG的无散水提供了新的氮的主要来源，从而对碳循环进行了直接控制。二氧化碳的海洋吸收会导致该生态系统海水中二氧化碳（PCO2）的长期变化。 因此，了解碳系统的扰动如何影响海洋生物地球化学是一项重要且及时的事业。在该项目中，研究人员将研究N2固定微生物的天然组合如何对海水碳化学的扰动做出反应。实验室和基于现场的实验将放置在每月时间序列测量的背景下，以固定微生物丰度的活动和丰富性。该项目一起将洞悉N2固定微生物生理学对CO2变化的依赖性。 该研究的广泛目的是：（1）量化海水PCO2变化对海洋重18Zotrophs自然构造的生长和社区结构的反应和后果； （2）确定海水PCO2的变化为什么以及如何影响两种模型海洋重物营养（Trichodesmium and Crocosphaera）的生长和碳获取策略； （3）量化重18zotroph社区结构和活动的时间变化。更广泛的影响包括对气候变化情景对海洋生物地球化学的潜在影响提供重要的见解，这对微生物生态学家，气候变化科学家和生物地球化学家很有价值。此外，计划了本科生和研究生的研究机会，重点是妇女和代表性不足的科学群体的参与。