Volcanoes, vegetation, and food in Japan

Abstract

  In the Japanese Islands, there is much rainfall in the rainy season, and the temperature is high in the summertime, which promotes the growth of rice. In the wintertime, there is much snowfall on the mountains in the areas facing the Sea of Japan, which results in bringing the meltwater in summer to the rice fields in those areas. Two thirds of the land is covered with mountain forests, in a big portion of which Japanese cedar trees (Cryptomeria japonica) are growing particularly after plantation following the World War Two. There are 110 volcanoes (about 10% of all of the volcanoes in the world) ; eruption, earthquake and tsunami are associated with the presence of volcanoes. The massive precipitation on the lands may every year deplete water-soluble minerals from the soil surface, thereby constantly diminishing the content in the soil of potassium and phosphorus which are indispensable for plant growth. The author thinks that the volcanic ash from infrequently-but-regularly occurring eruptions are replenishing the soil with these minerals for the annual harvest of rice as well as for the growth of the cedar trees. Masao Otsuki, an agricultural economist, once called Japan as “The Country of Rice and Cedar.” Accumulation of rice grains helped to establish Yamato Imperial Court. Armada ships made of the cedar tree were sent to the Korean Peninsula in 663. Architectural techniques used for building the large ships were applied for constructing large palatial buildings in the Fujiwara Metropolis in 694. The natural environment with volcanoes and earthquakes may have made the residents make up cultures with polytheistic character.