individual publications

• academic article

  • Excess Nitrogen in the U.S. Environment: Trends, Risks, and Solutions..  Issues in Ecology.  15. 2012
  • Nutrient Imbalances: Pollution Remains, Response.  Science.  326:665-666. 2009
  • Soil microbial dynamics in Costa Rica: seasonal and biogeochemical constraints.  Biotropica.  36:184-195. 2004
  • Human health effects of a changing global nitrogen cycle.  Frontiers in Ecology and the Environment.  1:240-245. 2003
  • Global patterns of terrestrial biological nitrogen (N2) fixation in natural systems.  Global Biogeochemical Cycles.  13:623-645. 1999

• chapter

  • The global nitrogen cycle, biodiversity, and human health.  Biodiveristy Change and Human Health. 159-178. 2009

• report

  • Excess nitrogen in the U.S. environment: Trends, risks, and solution. 2012