Effect of rainfall forecast accuracy on water management under variable rate irrigation system
LI Xiumei, ZHAO Weixia, LI Jiusheng*, LI Yanfeng
State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100048, China
Abstract:To use the rainfall effectively and improve the water management of variable rate irrigation, the rainfall forecast data were combined with the irrigation schedulings to generate the prescriptions. Based on the accuracies of rain forecast in the 2016 and 2017 seasons, the effect of the rainfall forecasts over a forthcoming three-day period on the irrigation schedulings of winter wheat and summer maize under variable rate irrigation system was studied. Results showed that the accuracy of rain forecast was not obviously different in the future 1 to 3 days. The accuracy was high up to 83.3% in forecasting no rainfall, followed by the high and heavy rain, which was 51.7%. The accuracy was 23.0% in forecasting moderate rainfall. The water savings in winter wheat in the 2016 season and summer maize in the 2017 season by using the rain forecast data were 8 mm and 16 mm, respectively. Consi-dering the accuracy of rain forecasts, the calculated irrigation water could be applied if no rain and light rain were forecasted. When the moderate rain was forecasted, 80% of the irrigation quota could be applied. When the high and heavy rain was forecasted, the irrigation event could be triggered later.
李秀梅, 赵伟霞, 李久生*, 栗岩峰. 降水预报准确率对变量灌溉水分管理的影响[J]. 排灌机械工程学报, 2018, 36(10): 985-989.
LI Xiumei, ZHAO Weixia, LI Jiusheng*, LI Yanfeng. Effect of rainfall forecast accuracy on water management under variable rate irrigation system. Journal of Drainage and Irrigation Machinery Engin, 2018, 36(10): 985-989.
[1]GB/T 34810—2017作物节水灌溉气象等级 玉米[S]. 北京:中国标准出版社.[2]GB/T 34811—2017作物节水灌溉气象等级 小麦[S]. 北京:中国标准出版社.[3]BERGEZ J E, GARCIA F. Is it worth using short-term weather forecasts for irrigation management[J]. European journal of agronomy, 2010, 33(3): 175-181.[4]TOGLIATTI K, ARCHONTOULIS S V, DIETZEL R, PUNTEL L, et al. How does inclusion of weather forecasting impact in-season crop model predictions?[J]. Field crops research, 2017, 214: 261-272.[5]侯静文,罗玉峰,崔远来.降雨预报准确度分析及其在水稻节水灌溉决策中的应用[J].节水灌溉, 2013(3): 24-30. HOU Jingwen, LUO Yufeng, CUI Yuanlai. Analysis of rainfall forecast accuracy and its application in water-saving irrigation decision-making for rice[J]. Water saving irrigation, 2013(3): 24-30.(in Chinese)[6]赵伟霞, 李久生, 杨汝苗, 等. 基于土壤水分空间变异的变量灌溉作物产量及节水效果[J]. 农业工程学报, 2017, 33(2): 1-7. ZHAO Weixia, LI Jiusheng, YANG Rumiao, et al. Yields and water-saving effects of crops as affected by variable rate irrigation management based on soil water spatial variation[J]. Transactions of the CSAE, 2017, 33(2): 1-7.(in Chinese)[7]LI X M, ZHAO W X, LI J S, et al. Application of deficit irrigation management to variable rate irrigation for winter wheat in sub-arid climates[C]//2017 ASABE Annual International Meeting, 2017.[8]ZHAO W X, LI X M, LI J S, et al. Water use and productivity of maize under different variable rate irrigation managements in sub-humid climates[C]//2017 ASABE Annual International Meeting, 2017.[9]汪翔, 叶金印, 陆琴琴. 冬小麦需水关键期的降水预报评估与应用对策分析[J]. 水电能源科学, 2015, 33(10): 6-9. WANG Xiang, YE Jinyin, LU Qinqin. Assessment of rainfall forecast and its application countermeasure for winter wheat’s critical period of water requirement[J]. Water resources and power, 2015, 33(10):6-9.(in Chinese)