Kudzu invasion doubles emissions of nitric oxide and increases ozone pollution
In a nutshell:
Kudzu is an invasive weed that has taken over large swaths of landscape in the Southeast United States. By fixing atmospheric nitrogen at a rapid rate, kudzu invasion may lead to significant release of nitric oxide, a precursor of regional ozone pollution. This project, led by Jonathan Hickman (formerly of Stony Brook, now at Columbia), investigated the effect of kudzu on air quality in the Southeast United States. In the field, Jonathan measured nitrogen fluxes in unaffected soil and soil invaded by kudzu, and found that nitric oxide emissions nearly doubled in the invaded soils. At Harvard, we fed Jonathan's data into the chemistry transport model GEOS-Chem. We calculated that the number of high ozone days in some parts of the Southeast could increase by more than 35 percent due to kudzu invasion, compared to a scenario with no kudzu. As global temperatures rise, the range of kudzu is likely to expand, with probable consequences for regional air quality.
Paper in PNAS
Hickman, J.E., S. Wu, L.J. Mickley, and M.T. Lerdau, Kudzu (Pueraria montana) invasion doubles emissions of nitric oxide and increases ozone pollution, Proceeding Nat. Acad. Sci., 107, (22) 10115-1-119, 2010. (pdf)
Press release and blurbs
Harvard: Climate scientists consider how kudzu increases ozone pollution
Stony Brook: Kudzu invasion doubles emissions of nitric oxide and increases ozone pollution
PNAS: Kudzu goes from bad to worse
Graphics (jpeg format)
1. Kudzu plant up close
2. Jonathan Hickman measuring nitric oxide back in the lab
Does kudzu cause ozone pollution?, Christian Science Monitor.
Kudzu spreading like, well, kudzu, CBS news
Invasive plant increases ozone pollution, BBC news
Kudzu linked to poor air quality, Los Angeles Times
Va. researcher finds that kudzu poses new threat, Washington Examiner.
Invasive Asian vine spreading through American South linked to poor air quality, Vancouver Sun.
Invasive kudzu is major factor in surface ozone pollution, study shows, Science Daily.
Invasive plants poison our air, Discovery News.
Curse of the kudzu, Climate Feedback blog, Nature.
Invasive plant will make you choke, The Great Beyond blog, Nature.
Study: Southern Ohio monitors spread of kudzu, WOSU public radio.
The authors acknowledge the support of the National Science Foundation Doctoral Dissertation Improvement Grant, the National Aeronautics and Space Administration (NASA-MAP NNG06GB48G), and the US Environmental Protection Agency (EPA-Star R83428601).
Go to the Harvard Atmospheric Chemistry Modeling Group webpage.
Back to Loretta Mickley's webpage.