Collaborative Research: Effects of Trophic Status Alterations on Pathways of Mercury Methylation in Northern Wetlands

合作研究：营养状况变化对北部湿地汞甲基化途径的影响

• 批准号: 1304804
• 负责人: Matthew Nugent
• 金额: $ 44.17万
• 依托单位: University of Massachusetts Lowell
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1304804&HistoricalAwards=false
• 关键词: Collaborative; Research; Effects; Trophic; Status

The overall hypothesis of this proposal is that the transition from ombrotrophic bogs to minerotrophic fens increases methylation rates and alters methylation pathways from those associated with microbial syntrophy and fermentation to those driven by anaerobic respiration, e.g., sulfate and iron reduction, in minerotrophic fens. This hypothesis is based on PIs? observations of (1) altered anaerobic decomposition pathways with the transition from bogs to fens in Alaskan wetlands, (2) dominance of syntrophic bacteria in an ombrotrophic bog, and (3) enhanced methylation by syntrophic microbial interactions. The hypothesis will be tested using a combination of field surveys and laboratory incubations that encompass chemical, biogeochemical and molecular analyses of wetlands representing trophic gradients in Alaska. The educational and outreach activities include: (1) production and dissemination of videos about the project and climate change; (2) the mentoring of students and a postdoctoral fellow; (3) hands-on field and laboratory experiences for high school students and teachers near PIs? institutions, and (4) high quality education of undergraduate and graduate students at both institutions through hands-on research and integration into classroom curricula, including student research funded by this project.

该提议的总体假设是，从富水沼泽到富矿沼泽的转变增加了甲基化速率，并将甲基化途径从与微生物合成和发酵相关的甲基化途径改变为由厌氧呼吸驱动的甲基化途径，例如，硫酸盐和铁还原。这个假设是基于PI？观察到（1）阿拉斯加湿地从沼泽到沼泽的转变改变了厌氧分解途径，（2）在湿养沼泽中互养细菌占主导地位，（3）互养微生物相互作用增强了甲基化。将使用实地调查和实验室孵化相结合的假设进行测试，包括化学，生物地球化学和分子分析的湿地代表阿拉斯加的营养梯度。教育和外联活动包括：（1）制作和传播关于项目和气候变化的视频;（2）指导学生和一名博士后研究员;（3）为项目研究所附近的高中学生和教师提供实地和实验室实践经验。（4）通过实践研究和纳入课堂课程，包括本项目资助的学生研究，在这两个机构为本科生和研究生提供高质量的教育。