朝阳地区干旱周期与演变规律研究

基于SPI标准化降水指标能反映干旱时间和空间分布特征的优点,将其作为干旱规律和周期的分析指标,然后利用功率谱分析法,对朝阳地区的干旱周期和干旱规律进行了研究。结果表明,朝阳地区是个旱情频发的区域,除极易发生轻旱外,还易发生中旱和特旱,秋冬季节会经常发生特旱,这为来年春天的播种带来困难;同时,朝阳地区旱涝呈现5～10年的周期性波动,具有一定的规律性和周期性。

Study on Drought Period and Evolution Law of Chaoyang Area

Based on the advantages of reflecting drought spatial and temporal distribution characteristics,standardized precipitation index(SPI) was used as analysis index to study drought period and rules of Chaoyang Area with power spectrum method.The results showed that Chaoyang was a frequent drought region.In addition to light drought,moderate drought and severe drought were also easily occur,especially in autumn and winter,which would brought lots of difficulties for sowing seeds in next spring.At the same time,the drought and flood period of Chaoyang was fluctuant from five to ten years,with certain regularity and periodicity.