Mapping maize cropping patterns and acreage is important to many stakeholders in Vietnam where official statistical data is not up-to-date. This study demonstrates the use of Savitzky - Golay and Support Vector Machine algorithms on a time series of Moderate Resolution Imaging Spectroradiometer Enhanced Vegetation Index data (2003 - 2018) to detect and map the maize cropping patterns on the sloping area of Son La province of Vietnam. The method was able to map the spatial distribution of maize cropping patterns in areas where cultivated acreages were highly fluctuated recently, with an overall accuracy of 81.6%. Districts' estimated maize acreages also show a good agreement with the official data at r = 0.75. Our findings suggest that a further improvement of the maize cropping pattern map can be made when higher spatial resolution remote sensing data are available and better presentative training samples for the whole region could be considered.
Hoang et al. (Wed,) studied this question.