Study on Crop Coefficients for Silage Maize and Alfalfa on Maowusu Sandy Land
Crop coefficient is an important parameter to estimate water requirement of crops. It has an important practical significance for agricultural production. The daily evapotranspirations of the reference crops of the silage maize and the alfalfa were determined in Maowusu sandy land using automatic measuring system of ENVIdata-DT for grassland transpiration. Then the daily crop coefficients of the silage maize and the alfalfa were calculated with Penmman-Monteith formula. Results showed that the mean of crop coefficient of silage maize in the whole growth period was 0.91. The difference of crop coefficient among different growth stages was small. Crop coefficient of alfalfa was increased with the increasing time in the first and second crops, and the crop coefficient sharply decreased after the first crop harvest on June 27, and average crop coefficient of the first crop was 0.87, and 0.85 for the second crop. A model was used to fit the crop coefficients of the silage maize and the alfalfa during growth period day by day with the number of days after sowing and accumulative temperature as independent variables. The results showed the model fitted the data of the crop coefficients well with the determination coefficient ofR2 in the range from 0.59 to 0.72.
Crop coefficientAlfalfaSilage maizeDays of after sowingAccumulative temperature
国家科技期刊平台
NSTL
万方数据
维普
