Traditional Utility System of the Environment of Naiko and Its Collapse in Villages Located on a Lagoon around Lake Biwa

Abstract

The aim of this paper is to reexamine the role of historical geography in studies of local environmental problems through analysis of a littoral zone landscape, particularly a coastal lagoon around Lake Biwa. There were more than 40 coastal lagoons around Lake Biwa, called Naiko in Japanese, but most had been reclaimed by the 1940s for the purpose of agricultural development. Although numerous studies have been made of national reclamation projects in the 1940s, little attention has been directed to the causes of degration of the environment of Naiko leading to the reclamation. In this paper, the author discusses the traditional lifestyle of the local people who made use of natural resources around Naiko before they were reclaimed, and the process of aggravation of the environment of Naiko, through a case study of Irie-naiko. This study clarifies the interactions among people, other organisms, and the environment of Naiko, i.e., the entire ecosystem of the littoral zone including human beings, by historico-geographical analysis of the landscape in each era since the premodern period.In Iso village, located on the shore of Irie-naiko, people's livelihood was traditionally based on a combination of subsistence fishery and rice cultivation. Many living activities utilized the natural resources of Naiko, such as waterbird hunting, reed gathering, water weed gathering, etc. Until the Taisho era, a diversity of traditional culture could be observed in utilizing the natural resources of naiko as well as biodiversity in this littoral zone. One of the important points to note is that the diversity of local culture functioned as a system for preserving the environment of Naiko. The environment of the Naiko and the traditional system for utilizing it began to collapse in the early years of the Showa era for several reasons. First, the national policy of maintaining a low water level in Lake Biwa caused a decrease in bioresources in Naiko. Second, the traditional combination subsistence in the village shifted exclusively either to fishery in Lake Biwa or to rice cultivation around Naiko. At the same time, the multiple values existing in the space of Naiko changed into the single value that Naiko were suitable for arable land. This specialization of space can be considered as a major factor in the reclamation promoted as a national project during wartime in the 1940s.