DISSERTATION RESEARCH, Funds for Jonathan E. Hickman: Effects of kudzu (Pueraria montana) on nitrogen oxide fluxes

不同的植物物种向大气中排放不同类型的气体。因此，植物群落组成的变化可能会导致生态系统产生的活性大气化合物发生重大变化，其中一些是对流层臭氧形成的关键前体。这笔赠款支持一项调查，调查入侵豆科植物葛根(葛根)的独特生理学如何导致美国东部生态系统规模的氮痕量气体通量的变化。葛根的氮氧化物排放量将在一系列潮湿条件下的普通花园环境中以及在田间入侵和未入侵的配对地点进行测量。还将测量一套氮气循环变量，以提供气体流量测量的背景。在葛根的大部分范围内，一氧化氮是对流层臭氧形成的限制性前体，即使是低水平的臭氧也对人类健康有害，会导致哮喘、增加对呼吸系统疾病的易感性和永久性的肺损伤。收集各种温度和湿度处理的氮氧化物排放数据，将与正在进行的葛根异戊二烯通量测量相结合，开发一个生态系统规模的模型，能够预测葛根如何影响臭氧形成和空气质量。公众宣传将包括对学校和公民团体的演讲，本科生将接受科学实践方面的指导。

Different plant species emit different types of gases to the atmosphere. Thus, a shift in plant community composition can result in large changes in an ecosystem's production of reactive atmospheric compounds, some of which are key precursors to tropospheric ozone formation. This grant supports an investigation into how the unique physiology of the invasive legume kudzu (Pueraria montana) contributes to changes in ecosystem-scale fluxes of nitrogen trace gases in the eastern United States. Nitrogen oxide emissions by kudzu will be measured in a common garden setting under a range of moisture conditions, as well as in paired invaded and un-invaded sites in the field. A suite of nitrogen cycling variables will also be measured to provide a context for the gas flux measurements. Throughout much of kudzu's range, nitric oxide is the limiting precursor to tropospheric ozone formation, which is detrimental to human health even at low levels, contributing to asthma, increased susceptibility to respiratory illnesses, and permanent lung damage. Collecting nitrogen oxide emission data across a range of temperatures and moisture treatments will be combined with on-going measurements of kudzu isoprene fluxes to develop an ecosystem-scale model able to predict how kudzu affects ozone formation and air quality. Public outreach will include talks to school and civic groups, and undergraduate students will be mentored in the practice of science.