都市水害論(2)-タイムスケール2000年における災害の変遷(つづき)-

Abstract

In the second report, using historical data of natural disasters, changes innatural water hazards are investigated in a time scale of 2000 years, in relation tochange in natural forces and social activities. Historical population change in everydistrict is considered in terms of change in social activities, such as construction ofirrigation structures for reclamation and cultivation. Changes in hazards such asdrought, typhoon, heavy rainfall and snow disasters, and their spatial changes areinvestigated in relation to changes in natural forces and social activities. Andchange in fire is considered relating to urbanization and rapid population increase aswell as weather condition. Using these data some relations between hazards arethen found.Historical changes in internal disturbances, such as riots and farmer disoders arealso considered relating to natural hazards and changes in population and socialactivities.