Collaborative Research: Ocean Acidification-Category 1: Effects of pCO2 and pH on Photosynthesis, Respiration and Growth in Marine Phytoplankton

合作研究：海洋酸化-类别1：pCO2和pH对海洋浮游植物光合作用、呼吸和生长的影响

• 批准号: 1041034
• 负责人: Brian Hopkinson
• 金额: $ 41.12万
• 依托单位: University of Georgia Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1041034&HistoricalAwards=false
• 关键词: Collaborative; Research; Ocean; Acidification; Category

Approximately one third of carbon dioxide emissions dissolve in the surface waters of the ocean and increase its acidity (the phenomenon of ocean acidification). Amongst the biological effects of seawater acidification are changes in the growth of phytoplankton, organisms that are the basis for marine food-webs. However, variable effects on phytoplankton growth of increasing carbon dioxide concentration have been reported, including an increase, no effect or a decrease. The objective of this project is to understand the physiological response of marine phytoplankton to increasing concentrations of carbon dioxide and acidity. This knowledge will make it possible to assess, and eventually predict, future changes in phytoplankton ecology and ocean productivity. The hypothesis to be tested is that the increase in carbon dioxide and the increase in acidity (a decrease in pH) both influence the growth of marine phytoplankton. It is postulated 1) that elevated carbon dioxide levels will lead to a higher photosynthetic efficiency, and 2) that a lower pH of seawater will decrease the energy that phytoplankton must spend to maintain their normal internal pH. Experiments will be carried out to test if differences in photosynthetic and respiratory physiology between phytoplankton species will result in different responses to carbon dioxide concentration and ocean acidity. These hypotheses will be tested in laboratory experiments and complementary field studies, using mass spectrometric techniques and the analysis of molecular markers to trace carbon and oxygen metabolism. Field experiments with natural phytoplankton will be carried out in New Jersey coastal waters, Bermuda, and iron-limited waters off California.Broader ImpactsThis project, which addresses an issue of significant concern to society, will provide research experiences for undergraduates and training for graduate students and a postdoctoral fellow. Summer interns from local junior colleges will participate in the project. A problem-based learning package on climate change and ocean acidification targeting middle and high school students and teachers will be developed. The principal investigators will work with Climate Central, a nonprofit organization that prepares media content for the web, television stations and other outlets that provide information to the public.

大约三分之一的二氧化碳排放溶解在海洋表面水域中，并增加其酸度(海洋酸化现象)。海水酸化的生物影响包括浮游植物生长的变化，浮游植物是海洋食物网的基础。然而，二氧化碳浓度增加对浮游植物生长的不同影响已有报道，包括增加、没有影响或减少。该项目的目的是了解海洋浮游植物对二氧化碳和酸度浓度增加的生理反应。这些知识将使评估并最终预测未来浮游植物生态和海洋生产力的变化成为可能。需要检验的假设是，二氧化碳的增加和酸度的增加(pH的下降)都会影响海洋浮游植物的生长。据推测，1)二氧化碳水平的升高将导致更高的光合作用效率，2)较低的海水pH将减少浮游植物维持其正常内部pH所需的能量。将进行实验，以测试浮游植物物种之间的光合作用和呼吸生理学的差异是否会导致对二氧化碳浓度和海洋酸度的不同反应。这些假说将在实验室实验和补充实地研究中得到验证，使用质谱学技术和分子标记分析来追踪碳和氧代谢。利用天然浮游植物进行的实地实验将在新泽西海岸、百慕大和加利福尼亚州附近铁有限的水域进行。广泛影响这个项目解决了一个备受社会关注的问题，将为本科生提供研究经验，并为研究生和博士后研究员提供培训。来自当地大专的暑期实习生将参与该项目。将开发以问题为基础的气候变化和海洋酸化学习包，面向初中生和教师。主要调查人员将与气候中心合作，这是一个非营利性组织，为网络、电视台和其他向公众提供信息的机构准备媒体内容。