Comparison of spatial interpolation methods for maize growth period

For guiding the cultivation of different regions, accurately estimating the maize growing period of the main maize-growing areas is of great significance. The different methods of interpolation principle were studied, such as inverse distance weighting(IDW), radial basis functions(RBF), and Kriging. Data source of five stages summer maize growing period was deal with spatial interpolation in the Huang-Huai-Hai summer maize area. The final surface accuracy was analyzed by the cross-certification. The results showed that in the sowing stage or seeding stage, or maturity stage, the most suitable method for interpolation was RBF, of which root-mean-squares were 5.077, 5.320, 5.243 d, while in the jointing stage and heading stage, interpolation of the best method was IDW, of which root-mean-squares were 7.826, 6.403 d. The distribution of sowing and seeding from southwest to northeast was gradually postponed, and the remaining stages of reproductive age, on both sides based on the axis of southeast and northwest were gradually postponed.