Nitrogen deposition in California forests: a review. Envir

Atmospheric oncentrations and deposition of the major nitrogenous ( N) compounds and their biological effects in California forests are reviewed. Climatic characteristics of California are summarized in light of their effects on pollutant accumulation and transport. Over large areas of the state dry deposition is of greater magnitude than wet deposition due to the arid climate. However, fog depo-sition can also be significant in areas where seasonal fogs and N pollution sources coincide. The dominance of dry deposition is magnified in airsheds with frequent empera-ture inversions such as occur in the Los Angeles Air Basin. Most of the deposition in such areas occurs in summer as a result of surface deposition of nitric acid vapor (HN03) as well as particulate nitrate (NO3-) and ammoniu