Dissertation Research: Anaerobic oxidation of methane coupled to denitrification in the Choptank Basin (MD USA)

甲烷是一种导致全球气候变化的强效温室气体，沿海水道中过量的氮会导致水质下降。一种新发现的微生物过程可以减少进入大气的甲烷和进入水道的氮的数量。 这种微生物过程将甲烷转化为效力较低的温室气体二氧化碳，将有毒的亚硝酸盐转化为不起反应的氮气。 然而，目前尚不清楚这种微生物过程是否在自然界中发生。 本研究将调查这一过程是否发生在自然界中，如果是的话，在什么速度，在农业地下水的海岸的马里兰州。 这项研究将提供有关农业系统中甲烷厌氧氧化与反硝化作用的速率的信息，农业系统往往具有高氮水平。 与以前所有仅在实验室中进行的有关这一过程的工作不同，该项目将使用在现场进行的实验来研究这一微生物过程。如果能更好地理解这种微生物过程，它可能被用作一种补救工具，以减少氮向周围沃茨的沥滤和甲烷排放。 这项研究的结果将与当地农民和利益相关者分享，以实施最佳管理实践，刺激这种新的微生物过程，减少农田中的氮和甲烷损失。 本项目将通过提供地球化学方法和仪器的经验，支持研究生和本科生的科学培训。

Methane is a potent greenhouse gas that contributes to global climate change, and excess nitrogen in coastal waterways can cause a decline in water quality. A newly discovered microbial process could reduce the amount of methane reaching the atmosphere and nitrogen reaching waterways. This microbial process converts methane into the less potent greenhouse gas carbon dioxide and toxic nitrite into unreactive nitrogen gas. However, it is not known if this microbial process occurs in nature. This study will investigate whether this process occurs in nature, and if so at what rate, in agricultural groundwater on the Eastern Shore of Maryland. This study will provide information on the rates of anaerobic oxidation of methane coupled to denitrification in agricultural systems, which tend to have high nitrogen levels. Unlike all previous work on this process that has occurred only in the laboratory, this project will investigate this microbial process using experiments conducted in the field. If this microbial process is better understood, it could potentially be used as a remediation tool to reduce the leaching of nitrogen into surrounding waters and methane emissions. Results from this study will be shared with local farmers and stakeholders in an effort to implement best management practices that would stimulate this new microbial process to reduce nitrogen and methane losses from farm fields. Scientific training of graduate and undergraduate students will be supported by this project through providing experience with biogeochemical methods and instrumentation.