Abstract |
As part of the overall process of evaluating the impacts of total atmospheric deposition of nitrogen on coastal ecosystems and estuaries, estimates of wet and dry deposition of nitrogen to both watershed and water bodies are required. Currently, most bays, estuaries, and watersheds lack onsite deposition monitoring data. In this first order attempt to assess the impact and fate of nitrogen delivered from atmospheric processes, estimates of wet and dry nitrogen deposition are derived using data from either regional monitoring activities of calibrated atmospheric deposition models. The components of estimated wet nitrogen deposition include, nitrate, ammonium and organic nitrogen. For dry deposition, the gas phase components include nitric acid vapor and ammonia, while the aerosol components consist of nitrate and ammonium. Total annual N deposition (wet plus dry) ranged from 3 to 14 kg N ha(-1), with wet deposition generally comprising about 60% of the total. |