根据甘肃省兰州市、白银市、定西市、临夏市、平凉市和庆阳市1981 — 2010年共30 a的气象站数据，依据各季节各站点累积降水量平均值划分干旱等级，分析了甘肃半干旱区季节性干旱的分布特征。结果表明，特大干旱、严重干旱、轻度干旱、中度干旱在甘肃半干旱区春季、夏季和秋季均有发生，其中春季以严重干旱和中度干旱为主，夏季以中度干旱和轻度干旱为主，秋季以中度干旱和轻度干旱为主。

Based on the meteorological data of stations of Lanzhou， Baiyin， Dingxi， Linxia， Pingliang and Qingyang in Gansu Province for a total of 30 years from 1981 to 2010， the drought level was graded according to the average precipitation at each site in each season， and the seasonal drought distribution characteristics were analyzed in the semi-arid region of Gansu Province. The results show that extreme drought， severe drought， moderate drought and mild drought occurred in spring， summer and autumn in the semi-arid region of Gansu Province. Among them， severe drought and moderate drought occured frequently in spring， mainly moderate drought and mild drought mainly occurred in summer and autumn.

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公益性行业(农业)科研专项“半干旱区(甘肃)主要作物抗旱稳产技术研究与示范”(201203031-05)。