Crop extent mapping using MODIS data in El Salvador

This study aimed to develop a mapping approach to investigate the extent of major crops (e.g., maize, beans, and sorghum) in El Salvador using MODIS data. We processed the data for 2011 through four main steps: (1) constructing the time-series enhanced vegetation index 2 (EVI2) data, (2) noise filtering of the time-series data with the empirical mode composition (EMD), (3) crop area mapping using phenogical information extracted from the smooth EVI2 data, and (4) accuracy assessment. The mapping results compared with the ground reference data indicated an overall accuracy of 82.7% and a Kappa coefficient of 0.65, respectively. The results also validated with the government's statistics of cropping areas at the department level confirmed a close correlation between the two datasets (R² = 0.77).