Denitrification in forest soils of Oregon

Denitrification represents a potential loss of N from forest soils as well as a source of N oxides to the atmosphere; however,this process has not been closely examined in forest ecosystems of the Pacific Northwest. The objectives of this study wereto survey in situ denitrification rates in a range of forest ecosystems and to assess the importance of selected soil propertiesas controlling factors of denitrification in forest soils. Soils from eight mature conifer stands, three recently clear-cut sites,and four Alnus rubra Bong. stands were sampled in spring, summer, and autumn. Denitrification potentials (anaerobicsoil slurries), in situ denitrification rates, soil respiration rates, soil water contents, and soil NO3 concentrations weremeasured. Denitrification potentials ranged from