1960—2015年吉林省玉米生长季有效降水和水分亏缺指数的变化特征

Variation of effective precipitation and water deficit index in maize growing season in Jilin Province during 1960—2015

利用吉林省1960—2015年50个气象站的气象数据、1981—2014年玉米生育期观测资料,分别采用FAO推荐的Penman-Monteith方法、参考作物蒸散量和降水量的比率法,计算玉米生长季及各阶段的需水量、有效降水量,进而计算水分亏缺指数并分析其变化特征。结果表明:吉林省近56年玉米生长季平均有效降水量为242~374 mm,变化趋势在^(-1)2.0~4.9 mm·10a^(-1),多数呈下降趋势,营养生长期有效降水在中西部大部、东部个别地区呈上升趋势,其它各生育时段以下降趋势为主。玉米生长季平均需水量为452~637 mm,气候倾向率在^(-1)6.5~10.3mm·10a^(-1),以下降趋势为主,生殖生长期需水量多数呈上升趋势,其它生育时段多数呈下降趋势。玉米生长季平均水分亏缺指数在23%~58%,气候倾向率在-0.8~1.9·10a^(-1)之间,以上升趋势为主,玉米营养生长期水分亏缺指数以下降趋势为主,其它生育阶段以上升趋势为主。中西部是有效降水量的低值区,需水量的高值区,水分亏缺严重;东部是有效降水量的高值区,需水量的低值区,水分亏缺相对较轻。

Based on the meteorological data from 50 weather stations during 1960 to 2015 and observation data of maize growth period during 1981 to 2014 in Jilin Province,the water requirement and effective precipitation in maize growing season and different growth stages during 1960 to 2015 in Jilin Province were estimated by PenmanMonteith equation. Further,the water deficit index in each growth stages of maize were calculated and analyzed in the study area. The results showed that average effective precipitation in maize growing season were between 242 ~374 mm,and the variation rate was^(-1)2.0 ~ 4.9 mm·10 a^(-1),showing a downward trend. The effective precipitation in vegetative phase had an upward trend in the most middle and west region as well as some of the east region,while other growth stages showed a downward trend. The average water requirement in maize growing season was between 452 mm and 637 mm,and the climate tendency rate was^(-1)6.5 ~ 10.3 mm·10 a^(-1) with a descending tend.Water requirement in reproductive phase mostly had an increasing trend,while other growth stages were mainly a decreasing trend. The average water deficit index in maize growing season was 23% ~ 58%,and the climate tendency rate was-0.8 ~ 1.9·10 a^(-1) with the most tend to ascend. Water deficit index in vegetative phase were mainly a decreasing trend,and it had an increasing trend in other growth stages. The middle and west region were the low area of effective precipitation,but they were the high area of water requirement,so that the water deficit were serious.The east region was the high area of effective precipitation,but it was the low area of water requirement,so that the water deficit was relatively slight.