平凉地区为旱作农业区 ,干旱是影响平凉地区农业生产的主要气象灾害之一 ,且具有持续时间长、影响范围广、危害程度重的特点。按农作物的生育期考虑 ,主要有春旱、春末初夏旱、伏旱和秋旱。因此 ,分析这四个时段干旱的气候特征和时间变化规律 ,使人们对我区的干旱时空分布特征 The Pingliang area is a dry farming area, and the drought is one of the major meteorological disasters that affect the agricultural production in Pingliang area. It has the characteristics of long duration, wide impact range and heavy damage. According to the crop growth period to consider, mainly spring drought early spring drought, drought and autumn drought. Therefore, the analysis of the climatic characteristics and temporal variation of the drought over the four periods of time makes it possible for people to analyze the spatial and temporal distribution of drought