Author(s): Xin Han; Baozhang Zhang; Zheng Wei; He Chen; Yinong Li; Taisheng Du
Linked Author(s):
Keywords: Reference crop evapotranspiration (��0 ); Evapotranspiration (��� ); Crop coefficient method; Prediction model
Abstract: The prediction of crop evapotranspiration (���) is critical for making reasonable irrigation plan and improving water use efficiency, and the meteorological factors have a great effect with the ���. To construct the prediction model of ��� in the whole growth period of winter wheat, the meteorological observation data of 2000-2015 and the historical weather forecast data of 2014-2015 were collected in Daxing District, Beijing, China. The modified Penman Monteith (PMT), Hargreaves (HAG) and McCloud (Mc) models were adopted to predict reference crop evapotranspiration (��0), and then the ��� prediction models were established based on the crop coefficient method (FAO-56). In addition, the prediction of ��� was verified by the observed from Eddy Covariance. Results showed that, PMT, HAG, and Mc models had high prediction accuracy for ��0,among which Mc model had the highest accuracy, with the R 2 of more than 0.76, the absolute error and RMSE were less than 1.3mm/d, and the prediction accuracy (error < 1mm/d)was more than 74%. Among the ��� prediction models verified by Eddy Covariance, Mc prediction model also had high accuracy, the consistency index wer e more than 0.78, MAE were less than 0.146mm/d, and the prediction accuracy (<2mm) were more than 80.59%, which could meet the estimation accuracy of ��� in the study area.
Year: 2020