明代关中地区干旱灾害时空特征

[目的]探讨明代关中地区干旱灾害的时空特征。[方法]通过对关中地区明代(公元1368~1644年)干旱灾害资料的搜集、整理,对明代277 a中关中地区发生的旱灾的划分等级、频次、受灾范围以及时空特征进行了分析,比较了各个县的发生频次和受灾程度。[结果]在明代277 a中,关中地区发生干旱灾害共145次,基本上平均每1.91 a发生1次。根据干旱等级分为轻度干旱、中度干旱、大旱灾和特大旱灾。并且旱灾具有周期性和季节性,主要表现为夏旱、秋旱、冬旱、春旱和连旱。从明代前期到后期,干旱灾害发生频次具有显著波动变化的特征,而且持续时间长,灾情严重,其中宝鸡地区发生次数高于其他地区。[结论]在明代的277 a中,关中地区发生灾害基本上呈现增加趋势,为当前关中地区的防灾减灾提供了理论依据。

Spatial and Temporal Characteristics of Drought Disaster in the Central Shaanxi Plain in Ming Dynasty

Objective] The aim was to discuss the temporal and spatial characteristics of drought disasters in the central Shaanxi Plain in Ming Dynasty.[Method] Through collection of drought disaster data in the central Shaanxi Plain in Ming Dynasty(AD 1368-1644), the grade, fre-quency, range, spatial and temporal characteristics of drought disaster in the central Shaanxi Plain were analyzed , the frequency and disaster de-gree in each county was compared.[Result] In Ming Dynasty 277 years, there were 145 times drought disaster totally in the central Shaanxi Plain, with the average rate of 1.91 each year.According to drought level, there were mild drought, medium drought, great drought and espe-cially big drought.Drought disaster was featured by season, which was composed by drought in summer, autumn, winter, spring.From the earli-er stage to the later stage of Ming Dynasty, the drought rate was fluctuated, longer and serious.Among them Baoji suffered the disaster more than other areas.[ Conclusion] During 277 years of Ming Dynasty, the trend of disasters in the central Shaanxi Plain presented an increasing trend , which can provide theoretical basis for preventing and reducing disasters in the central Shaanxi Plain .