抄録
Total nitrogen (TN) concentration was surveyed at 31 streams in a forested mountain area (Aoya River basin; 4, 500 ha) located in the central part of Japan. A statistical analysis was applied to the TN data and the factors representing the state of the land coverage such as geologic feature, soil species, forest tree species, forest age, growth rate of trees, stem volume of trees, etc. Among these factors, the rate of the brown forest soil and the population of the deciduous coniferous forest showed a positive influence on the TN concentration. The growth rate and the stem volume of trees have a negative contribution to the TN.
