陆浑灌区主要气象因素与作物需水量的演变特征分析

Evolution Analysis of Main Meteorological Factors and Crop Water Requirement of Luhun Irrigation Area

针对陆浑灌区极端天气频发的问题,利用陆浑灌区1951-2013年逐日气象资料,采用小波分析对灌区降水量、平均气温及作物需水量（ET0）进行一般趋势分析及多时间尺度周期分析,运用Mann-Kendall法对各气象要素进行突变检验。结果表明,陆浑灌区的年降水量呈下降趋势,其中秋季降水减少对灌区年降水量下降贡献最大;气温、ET0呈上升趋势,春季气温上升对灌区气温升高贡献最大,夏季ET0的增加对灌区ET0增加贡献最大;陆浑灌区气温突变点在1998年,ET0的突变点在1974、2012年,灌区降水量年际变化不稳定使得突变点较多,分别在1958、1981、1986年;气温与ET0的波动主周期高度一致,均为7、17、30年,说明气温对灌区ET0的贡献相对较大。

The problem of extreme weather in Luhun irrigation area is so serious and frequent.By using the date of the Luhun irrigation daily meteorological available from 1951 to 2013year,wavelet analysis method is used to analyze the general trend change and multi-time-scale periodicity of annual precipitation,average temperature and crop water requirement（ET0）.And then the Mann-Kendall method is adopted for sudden change test.The results show that the annual precipitation is on the decline,and the autumn precipitation decreases on the largest contribution to the annual precipitation falling in the irrigation area.The temperature and ET0 rise,and at the same time spring on the largest contribution to the irrigation temperatures.For ET0,the largest contribution is the increase of ET0 in summer.The sudden change point of the temperature appears in 1998,and the sudden change point of ET0 appears in 1974 and 2012.While the annual precipitation＇s trend is unstable,thus making the sudden change points more than others,which appear in 1958,1981and1986.The temperature and ET0 are highly consistent,fluctuations in the cycle for 7a,17 a,30a,which show that the temperature＇s contribution to the ET0 is relatively large.