Satoyama

Satoyama is a part of Japanese rural landscape developed by centuries of agricultural use. The concept of satoyama has several definitions. The first definition of satoyama is the management of forests through local agricultural communities. During the Edo era, community forests were used to gather young leaves and fallen leaves for the wet rice paddy fields as fertilizer. Villagers also used wood for construction of buildings and for cooking and heating. In a more recent definition, satoyama means not only mixed community forests, but also the whole landscape that is used for agriculture. According to this definition, satoyama contains a mosaic of mixed forests, rice paddy fields, dry rice field, grasslands, streams, ponds, and reservoirs for irrigation. Farmers used grassland to feed horses and cattle. Streams, ponds, and reservoirs played am important role to adjust water levels of the patty fields and to provide fish as food.^[1]

Human Population, Ownership, Landuse

The decreasing of population in villages is considered as a factor that drives satoyama disappear from Japanese mountains. The depopulation of villages has occurred because of recent economic events, which have created significant social and economic gaps between people in a modern city and people in a mountain village. Moreover, natural conditions such as steep slop, snowfall have led people to stay away from satoyama. Speaking of ownership, inhabitants in satoyama located the shared ownership of common forests closed to their village in the beginning of 19th century. These forests were logged for making money and the construction of houses. Therefore, today, we often see old-age forests, including beech in high elevations far from a village. Inhabitants use their private forests as fuel wood, and conifer plantations. By the 1960s, satoyama was used as rice fields, plowed fields, shifting cultivation, grasslands, thatch fields, secondary forests for fuel, and giant bamboo forests. ^[2]

Various habitat types for wildlife have been provided by mixed satoyama landscape as a result in Japanese traditional agricultural system. It also facilitated the movement of wildlife between a variety of habitats. The migration of wild animals can occur among the ponds, rice paddy fields, grasslands, forests, and also from one villege to a different village. Because of these ecosystems, a rich biodiversity in the Japanese rural area was maintained. Especially, mosaic type of ponds, reservoirs, and streams played a significant role for the survival of water dependent species such as dragonflies, and fireflies. In early stage of their life cycle, they spend most of their time in water. Through maintaining a mixture of successional stages by the agricultural activities and the management of satoyama, the preservation and promotion of biodiversity are facilitated. For instance, Japanese oaks and Japanese chestnut oaks are planted by farmers to maintain deciduous broad-leaf trees. Succession to dense and dark laurel forest is prevented due to the fact that farmers cut down these trees every 15 to 20 years to gain fuelwood and charcoal. Most of plant and animal species live in these deciduous forests only through the traditional management practices. Therefore, much more wildlife can be supported by well managed forests than dark unmanaged laurel forests. ^[3]

Satoyama has been disappeared due to the drastic shift in natural resources from charcoal and firewood to oil, the change from compost from chemical fertilizer. Also, the problem of aging in Japanese society can cause the disappearing of satoyama because there are fewer people who can work in Satoyama. Because of those human impacts such as harvesting trees for timber and charcoal, cutting shrubs for firewood and collecting litter as compost, the success of the forest occurred. Furthermore, pine dominated secondary forests were increasingly destroyed since pine wilt disease devastated pine forests in the 1970.^[4][5]

In 1980-1990s, the movement of the conservation of satoyama occurred in all over Japan since people came to understand the value of satoyama for Japanese ecosystems and their life. Currently, there are more than 500 environmental groups that work for the conservation of satoyama. The main problem of satoyama today is that because of the depopulation in satoyama, people do not cut down old growth trees which can support less biodiversity in satoyama than secondary growth forests. So, volunteers from the groups monitor satoyama to determine when to harvest trees appropriately. They also educated young people to teach how satoyama is important historycally and ecologically and how the conservation of satoyama should be managed. Because of their efforts, the situation in satoyama in certain regions has been looking up well.^[6]