Abstract
The causes of tree death observed in 1994 and 1995 in Mikawa region, Aichi prefecture were analyzed by using GIS (Geographical Information System) extensively. The factors of topography, altitude, soil type, tree species, geology, precipitation, and oxidant concentration were used for the analysis. The analytical results showed that there was no relationship between geology, soil types or precipitation, and tree death. We found that most of the damaged areas were located at 200'400 m altitude along the major rivers. These locations are considered to be easily affected by polluted air invaded through valleys of the major rivers from the upper air above Ise Bay and Mikawa Bay, where high concentration of oxidant was observed. These results suggest that a chronic stress by polluted air such as oxidant might cause tree decline in Mikawa region.
