三瓶演習林およびその周辺における森林渓流水質の空間的変化

Streamwater chemistry was investigated at 24 collection points in three catchments (one broadleaf forest and two coniferous plantations ) around the Sambe Forest.Na^+ and CL^- concentrations were relatively uniform among the streams and higher than Japan's average, probably due to the influence of sea salt. Mean Ca^2+ and Si concentrations were higher in the coniferous rate in soils were greater in the coniferous plantations. Relatively high concentration of NO_3- was observed in the streamwater in the coniferous plantations. Maximum No_3- concentration from one coniferous plantation was comparable to that from urban forests where anthropogenic disturbance in N cycling was concerned. Contrary, NO_3- concentration from the broadleaf forest was much lower than Japan's average, and higher retention capacity of atmospheric N deposition can be expected in this broadleaf forest. Concentrations of Mg^2+, Ca^2+, NO_3- and HCO_3- decreased downstream in the coniferous plantations, while those in upstream water varied among the stream.