1:45 PM - 2:15 PM
[MIS17-01] Water Resources and Disasters in Medieval Japan
★Invited Papers
Keywords:Medieval history of Japan, Disaster history, Water resource
In recent years, due to global environmental changes such as climate warming, damaging large earthquakes, volcanic eruptions, floods, and typhoons have occurred successively in and around Japan. Crisis response to natural disasters has become a significant societal concern. In other words, the procurement of resources and the response to natural disasters have become important factors to consider in contemporary society.
Looking back at history, it is evident that conflicts over resource acquisition became causes of disputes at various levels, necessitating the adjustment of interests. Additionally, it is well-known that societal chaos resulting from natural disasters, famine, and epidemics has caused political upheavals and conflicts. Therefore, the examination of the circumstances surrounding resource procurement and responses to natural disasters in each era is an important theme that allows us to comprehend history and the present from a broad perspective.
Therefore, in this presentation, I aim to uncover the history of the alterations in the landscape and the impact on the occurrence of water disasters resulting from the construction of irrigation channels (Inseki) carried out in the Kofu Basin, around the Kai Province (present-day Yamanashi Prefecture) during the medieval period, specifically in the 16th century. The Yamanashi Prefecture region, comprising approximately 80% forested area, experienced frequent water disasters due to rivers flowing into the basin from the surrounding Akaishi, Koma, Misaka Mountains, etc. In the 16th century, extensive flood control projects such as the Ryuo Shingen Levee, in Kai City, were implemented. Exploring the utilization of water resources and disasters in this region becomes an important research subject. While the aspects of securing water resources and responding to water disasters have been discussed separately in previous research, here I attempt to comprehensively address both facets.
Firstly, we focus on the case of the irrigation channel known as "Yokosegi" or "Ichinosegi" (Yamanashi City), which draws water from the Fuefuki River flowing in the eastern part of the Kofu Basin. We highlight the Oimata Kubo Hachiman Shrine, which took control of the rights to water use in this irrigation channel. By managing this irrigation channel, the shrine took on the responsibility of securing water resources and responding to water disasters in the local Yawata District, thereby overseeing agricultural management. This led to the mobilization of the local population for the maintenance and management of the irrigation channel, harnessing their labor force for construction efforts. Additionally, the development of the Yokosegi and Ichinosegi channels resulted in the gradual urbanization and cultivation of the areas surrounding the shrine, transitioning from the traditional land division of alluvial fan to the development of island-shaped fields along the Fuefuki River. This shift altered the landscape of the region significantly.
Next, we examine the case of the irrigation channel called "Kamijo Segi" (Kai City), which draws water from the Kamezawa River, belongs to the Arakawa River system flowing through the central part of the Kofu Basin. This example shows that villages located at the fan top and fan center of the Arakawa alluvial fan, less susceptible to the direct impact of flooding from the main stream of the Arakawa River (Kamanashi River), became the area of water disasters in the late 16th century caused by the so-called backwater phenomenon resulting from the excessive water levels of the Kamanashi River. This highlights how securing and utilizing water resources brought about results in the local community, causing a dichotomy where development progressed on one hand while inducing natural disasters on the other.
Thus, while securing and utilizing water resources to facilitate development brought about changes in the local landscape, it also became a cause of natural disasters. To reconcile this contradictory situation of securing water resources while responding to water disasters and to mitigate conflicts between villages or within villages, it is believed that temples and shrines that has with religious area in the local communities, as well as feudal lords who established broad territorial control during the Sengoku period, assumed roles to mobilize the local population and suppress conflicts. They were expected to play a crucial role in bringing together the inhabitants of the region to coordinate efforts in addressing water-related challenges and maintaining stability within the community
Looking back at history, it is evident that conflicts over resource acquisition became causes of disputes at various levels, necessitating the adjustment of interests. Additionally, it is well-known that societal chaos resulting from natural disasters, famine, and epidemics has caused political upheavals and conflicts. Therefore, the examination of the circumstances surrounding resource procurement and responses to natural disasters in each era is an important theme that allows us to comprehend history and the present from a broad perspective.
Therefore, in this presentation, I aim to uncover the history of the alterations in the landscape and the impact on the occurrence of water disasters resulting from the construction of irrigation channels (Inseki) carried out in the Kofu Basin, around the Kai Province (present-day Yamanashi Prefecture) during the medieval period, specifically in the 16th century. The Yamanashi Prefecture region, comprising approximately 80% forested area, experienced frequent water disasters due to rivers flowing into the basin from the surrounding Akaishi, Koma, Misaka Mountains, etc. In the 16th century, extensive flood control projects such as the Ryuo Shingen Levee, in Kai City, were implemented. Exploring the utilization of water resources and disasters in this region becomes an important research subject. While the aspects of securing water resources and responding to water disasters have been discussed separately in previous research, here I attempt to comprehensively address both facets.
Firstly, we focus on the case of the irrigation channel known as "Yokosegi" or "Ichinosegi" (Yamanashi City), which draws water from the Fuefuki River flowing in the eastern part of the Kofu Basin. We highlight the Oimata Kubo Hachiman Shrine, which took control of the rights to water use in this irrigation channel. By managing this irrigation channel, the shrine took on the responsibility of securing water resources and responding to water disasters in the local Yawata District, thereby overseeing agricultural management. This led to the mobilization of the local population for the maintenance and management of the irrigation channel, harnessing their labor force for construction efforts. Additionally, the development of the Yokosegi and Ichinosegi channels resulted in the gradual urbanization and cultivation of the areas surrounding the shrine, transitioning from the traditional land division of alluvial fan to the development of island-shaped fields along the Fuefuki River. This shift altered the landscape of the region significantly.
Next, we examine the case of the irrigation channel called "Kamijo Segi" (Kai City), which draws water from the Kamezawa River, belongs to the Arakawa River system flowing through the central part of the Kofu Basin. This example shows that villages located at the fan top and fan center of the Arakawa alluvial fan, less susceptible to the direct impact of flooding from the main stream of the Arakawa River (Kamanashi River), became the area of water disasters in the late 16th century caused by the so-called backwater phenomenon resulting from the excessive water levels of the Kamanashi River. This highlights how securing and utilizing water resources brought about results in the local community, causing a dichotomy where development progressed on one hand while inducing natural disasters on the other.
Thus, while securing and utilizing water resources to facilitate development brought about changes in the local landscape, it also became a cause of natural disasters. To reconcile this contradictory situation of securing water resources while responding to water disasters and to mitigate conflicts between villages or within villages, it is believed that temples and shrines that has with religious area in the local communities, as well as feudal lords who established broad territorial control during the Sengoku period, assumed roles to mobilize the local population and suppress conflicts. They were expected to play a crucial role in bringing together the inhabitants of the region to coordinate efforts in addressing water-related challenges and maintaining stability within the community