Faculty Research Fellows Hutyra and Templer Publish Global Synthesis on Urban Nitrogen Deposition

Lucy Hutyra and Pamela Templer, Professors in the Departments of Earth & Environment and Biology, respectively, and Faculty Research Fellows at the Frederick S. Pardee Center for the Study of the Longer-Range Future, recently co-authored a paper related to their Pardee Center research on urban nitrogen deposition. The lead author of the paper was Stephen Decina, formerly of the Templer Lab, who successfully defended his PhD in 2017. The paper, titled “Hotspots of nitrogen deposition in the world’s urban areas: a global data synthesis,” was published in the journal Frontiers in Ecology and the Environment.

The global nitrogen cycle has been altered by human activities, leading to rates of atmospheric deposition up to ten times higher than pre-industrial levels. The largest contributor of nitrogen deposition is ammonia emissions, which are mostly unregulated by national governments. Elevated nitrogen deposition levels are harmful to humans and the environment, leading to eutrophication, soil acidification, and poor air quality.

As the human impact has become more apparent, more attention has been paid in recent years to nitrogen deposition rates in urban areas, as opposed to the rural areas where these studies have historically been conducted. In the paper, the authors synthesize data from 174 publications over the past 40 years that examine nitrogen deposition rates in urban areas. This meta-analysis helps quantify total urban nitrogen deposition, identify regional hotspots (particularly China), and demonstrate that deposition in cities is primarily the result of human sources like ammonia emissions.

Download the paper here.

As Pardee Center Faculty Research Fellows, Hutyra and Templer lead a project that established the first urban nitrogen monitoring stations in Boston (on the BU campus and throughout the City of Boston) as part of the National Atmospheric Deposition Program (NADP). This urban monitoring network complements the larger biogeochemistry research program at BU, which is seeking to understand the sources and transformations of emissions and deposition of nitrogen in Boston in order to make predictions about future atmospheric nitrogen deposition rates.