关中地区清代干旱灾害研究

通过对清代关中地区历史资料的搜集、整理和数学分析,对该时期关中地区的干旱灾害等级及其成因进行了研究.结果表明:关中地区从1644-1912年的267年中,共发生干旱灾害103次,平均每2.6年发生1次;轻度旱灾37次,占旱灾总数的35.9%;中度旱灾发生44次,占旱灾总次数的42.7%;大旱灾发生17次,占旱灾总数的16.5%;特大旱灾发生5次,占干旱灾害总数的4.8%;从清代早期到晚期干旱灾害呈现出增加的趋势,并具有显著波动变化特征.清代干旱灾害变化可分为2个主要阶段,在1644-1770年的126年为旱灾较低发生期,在1770-1909年的141年为旱灾较高发生期.年降水量的明显减少和降水分配不均是该区发生干旱灾害的主要原因.

Study on Drought Disasters in the Guanzhong Region in the Qing Dynasty

After collecting,interpreting and analyzing the history data of drought disasters in the Guanzhong region in the Qing Dynasty,in this paper the grades and formation causes of drought disasters in the study area are analyzed.The results show that 103 drought disasters occurred in the Guanzhong region during the period from 1644 to 1912 A.D.,and the disasters occurred once every 2.6 years;in which the slight,moderate,serious and extremely serious drought disasters were 37,44,17 and 5 times and accounted for 35.9%,42.7%,16.5% and 4.8%,respectively.During the period from the early stage to the late stage of the Qing Dynasty,the occurring frequency of drought disasters was in an increase trend in a significant fluctuation way.Occurrence of drought disasters in the Guanzhong region in the Qing Dynasty can be divided into two main periods,that is,the occurring frequency of drought disasters was relatively low in 126 years from 1644 to 1912 A.D.,and it was relatively high in 141 years from 1770 to 1909 A.D.The main causes resulting in the occurrence of drought disasters in the study area were the obvious decrease of annual precipitation and the uneven distribution of precipitation.Annual precipitation in the years when serious drought disasters occurred decreased generally by about 200 mm comparing with that in normal years,and it decreased by about 300 mm in the years when extremely serious drought disasters occurred.