1967—2017年甘肃省玉米需水量与缺水量时空分布特征

基于1967—2017年甘肃省28个气象站点的逐日气象数据,采用联合国粮食与农业组织(FAO,Food and Agriculture Organization of the United Nations)推荐的作物系数法计算了玉米各生育阶段和全生育期的需水量,结合美国农业部土壤保持局(SCS,Soil Conservation Service)推荐的方法计算了玉米全生育期的有效降水量,进而得到需水量。并利用线性倾向估计、Mann-Kendall检验和空间插值法对甘肃省玉米需水量和缺水量的年际变化趋势和空间分布特征进行分析。结果表明:1967—2017年甘肃省玉米全生育期平均降水量、平均有效降水量、平均需水量和平均缺水量分别为210.43、113.21、545.95 mm和421.00 mm;在时间上,51年来,甘肃省玉米全生育期内的降水量和有效降水量整体上呈明显的下降趋势,而需水量和缺水量整体上没有明显的变化趋势,属于正常波动;在空间上,玉米全生育期的降水量和有效降水量整体上由东南向西北减少,而需水量和缺水量整体上由东南向西北增加。28个站点中,51年来只有甘南和岷县站点的有效降水量...

Spatial and temporal characteristics of water requirement and water deficit of maize in Gansu Province from 1967 to 2017

Based on the daily meteorological data of 28 meteorological stations in Gansu Province from 1967 to 2017, the water requirement in different growth periods and the whole growth period of maize were calculated using the crops coefficient method recommended by Food and Agriculture Organization of the United Nations. Meanwhile, the effective precipitation in the whole growth period of maize was calculated by using the method established by the U.S. Department of Agriculture Soil Conservation. Thus, the water deficit was obtained. The interannual variation and spatial distribution characteristics of water requirement and water deficit in Gansu Province were analyzed by linear propensity estimation, Mann-Kendall test and spatial interpolation method. The results showed that the average precipitation, average effective precipitation, average water requirement and average water shortage during the whole growth period of maize in Gansu Province from 1967 to 2017 were 210.43 mm, 113.21 mm, 545.95 mm, and 421.00 mm, respectively. In past 51 years, the precipitation and effective precipitation in the whole growth period of maize showed a significant downward trend, while the water requirement and water deficit had no obvious change, which were normal fluctuation. In terms of space, the precipitation and effective precipitation in the whole growth period of maize decreased from southeast to northwest in general. On the contrary, the water requirement and water deficit increased from southeast to northwest on the whole. Among the 28 meteorological stations, only the effective precipitation of the Gannan and Minxian sites can meet the maize requirement water in the early growth stage in past 51 years. Other sites cannot meet the water requirement of maize at any stage of growth and require manual irrigation.