近50年重庆地区玉米干旱时空特征分析

Temporal and Spatial Distribution of Maize Drought in Recent 50a in Chongqing

本文利用重庆市34个代表气象站1961-2010年地面气象观测数据,结合FAO Penman-Monteith模型,基于作物水分亏缺指数(CWDI),研究分析玉米生育期内干旱指数的时空分布特征。结果表明,重庆地区玉米生长季内CWDI值西部>中部>东北部>东南部,2000年以来,水分亏缺指数值呈波动性上升趋势;玉米生长季内干旱频率分布特征为西部>中部>东北部>东南部,呈现由西北向东南递减趋势;各生育期以播种出苗期干旱发生频率最高,其次是拔节期、抽雄开花期,乳熟期干旱发生频率最小;2001年以来玉米干旱发生频率有增加的趋势。

Based on thirty-four representative meteorological stations in Chongqing as well as the ground meteorological observation data from 1961 to 2010,joining the FAO Penman Monteith model and the crop water deficit index （CWDI）,the temporal and spatial distribution of CWDI were calculated and analyzed.The results showed that the water deficit index value in Chongqing presented a fluctuated improving trend since 2000,and the western region had the most dramatic value of water deficit index during the maize growth season,followed by the central,northeast and southeast region; accordingly and the western rngion had the biggest drought frequency,followed by the central,northeast and southeast region,rendering a downward trend from northwest to southeast.For each growth period,sowing-seeding period has the most conspicuous drought frequency,followed by the jointing and tasseling flowering period.The milk-ripe stage possessed the least possibility for drought.The maize drought frequency had a tendency to increase since 2001.