BEACON
Research Vision

Background

Northern latitude forests play a significant role in the uptake and storage of atmospheric carbon, and of the various nutrients needed by forests, nitrogen is critically important. A fair amount of nitrogen reaches ecosystems via atmospheric deposition as a direct result of human activity, and this nitrogen is playing an increasing role in the fertilization of terrestrial and aquatic ecosystems. The complexity of atmosphere-forest interactions presents a significant challenge, one whose study requires expertise in atmospheric chemistry and speciated atmospheric fluxes as well as in plant physiology, soil microbiology and biochemistry, nutrient transfer and hydrologic balance. We are interested in engaging and bringing together for effective collaborative research, the atmospheric and biospheric research communities in the process of preparing a science plan to define the best possible approach to addressing questions involving nitrogen, and the connection to the carbon cycle.

Detailed Background Description

Motivating Questions

Prioritized Objectives

While we work to bring together the necessary participants for a coordinated and integrated effort, the PROPHET science team will be working to address some of the fundamental holes in our understanding of the deposition of speciated atmospheric nitrogen to forests.  Building on the strength of our experience in ambient atmospheric composition, we will focus our attention on fluxes of nitrogen species to the forest canopy and to the soils:  The following is a list of species that will be the immediate focus of our attention:
  1. Determine fluxes, and relative fluxes of HNO3, NO, NO2, particle nitrate, PANs and RONO2s.
  2. Determine the fractional throughfall for these species.
  3. Determine their fate after deposition.
  4. Investigate the importance of direct foliar uptake of atmospheric nitrogen compounds.
  5. Examine canopy surface transformation.