干旱对陇东及陇东南地区粮食产量的影响评估

干旱灾害是影响陇东南及陇东地区粮食生产的主要气候灾害。评估其对该地粮食生产的影响及粮食作物种植的风险程度,是干旱研究工作的目的之一。根据陇东南及陇东4市1981-2006年粮食产量及各地同期历年降水资料,借助数理统计方法分析了4市的干旱灾害变化的基本特征和该地冬小麦和玉米受干旱影响的减产程度,构造了评价冬小麦及玉米种植风险系数及评价方法。结果表明,陇东地区比陇东南地区更容易发生旱灾,春旱以陇东地区的庆阳最易发生且程度严重,初夏旱以陇东地区的平凉最易发生,伏旱以陇东南地区的天水最易发生。冬小麦的种植比玉米的种植风险大,陇东地区粮食作物的种植的风险比陇东南地区大。冬小麦种植风险最大的地方为平凉,其次为庆阳,最小的为陇南。玉米种植风险最大的地方是庆阳,其次为平凉,最小为陇南。

The Assessment on Influence of Drought to Yield of Crop in East and Southeast of Gansu

The drought is main disaster which affects yield of crops in southeast and east Gansu.One of the arid research work goal is to appraise the influence of drought to grain production and estimate the risk degree of crops planting.Based on date of yield of crops at 4 cities and the meteorological date in Southeast and East Gansu in 1981-2006,the characteristics of drought and the degree of reduction of wheat and corn output had been analyzed with mathematical statistic method and the methods of assessment and the risk coefficient had been set up.The results showed that the drought in the East of Gansu is serious than the Southeast of Gansu in that the spring drought is frequently in Qingyang city,the early summer drought is frequently in Pingliang city,the hot summer drought is frequently in Tianshui city.The degree of risk in planting wheat is high than in planting corn.The biggest risk in planting wheat area is Pingliang city,then Qingyang city,last Longnan city.The biggest risk in planting corn area is Qingyang city,then Pingliang city,last Longnan city.