Relation between Soil Acidification and Tree Decline of Historical Japanese Cedar (Cryptomeria japonica) Trees

A case of Iwa Shrine Forest in Hyogo Prefecture

Abstract

There are many forests of shrines in Japan that have long histories. In particular, Japanese cedar forests have been preserved as sacred forests. However, it is pointed out that forests have declined. Soil acidification is thought to be one of the causes of forest decline. We investigated the tree decline and soil acidification in Iwa shrine of Hyogo prefecture. Our study indicated that all of the trees surveyed showed decline and the soil pH of the trees was low and exchangeable nutrient base cations were low. The score of the tree decline is correlated with soil pH (r = - 0.57).