Extreme climate events, migration for cultivation and policies: A case study in the early Qing Dynas

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Based on the historical records of the annual increase in the workforce(men older than 16 years of age),the annual new taxed cropland in the Shengjing area (Northeast China),the extreme climate events in North China,and related management policies in Northeast China during 1661-1680,a case study has been conducted to investigate the relationship between the extreme climate events in North China and the migration to Northeast China for cultivation.This study has found that the migration to Northeast China for cultivation from 1661 to 1680 was a response to the drought events that occurred in North China.The upsurge of migration,which occurred in 1665-1680,was a response to the drought period during 1664-1680 in North China while the fewer disasters period in Northeast China.There were three migratory peaks during the upsurge of migration,which corresponded to the three drought events.The peaks of migration,however,often lagged behind the drought events about 1-2 years.The encouraging-migration policy,which was adopted to encourage cultivation in Northeast China,did not produce much migration into the region in the early Qing Dynasty.It did,however,provide a policy background,which ensured more than 10000 migrants per year to Northeast China when North China suffered from drought/flood disasters.As a response to the highest peak of migration induced by the severe droughts in North China during 1664-1667,a prohibiting-migration policy restricted further migration to Northeast China was carried out in 1668.Although the prohibiting-migration policy could not entirely stop the migrants fleeing from famine in North China to Northeast China,the migrants and cultivation were significantly reduced under the policy.The frequent changes of the policy on the years when taxation started after the land was cultivated were also related to climate events.The extreme climate events in North China,migration to Northeast China for cultivation,and the related management policies showed an impact-response chain,which reflected the interaction among extreme climate events,human behavior,and policies.
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