Resumen

Detection of maximum greenness in maize (Zea mays) using MODIS time series data in the Colonche parish of the Santa Elena province. RCTU [online]. 2025, vol.12, n.2, pp.70-79. ISSN 1390-7697.  https://doi.org/https://doi.org/10.26423/2qzfg896.

The aim of the research was to detect the moment of maximum greenness of maize in the parish of Colonche, Ecuador, using time series of the Normalized Difference Vegetation Index derived from the MODIS sensor. A total of 1 043 images from the MOD09A1.V061 product corresponding to 2001-2023 were analyzed, and time series were generated from the centroids of 200 plots classified as maize. To improve data quality, smoothing and a Savitzky-Golay filter were applied. Statistical analysis included autocorrelation, Ljung-Box Q test, periodogram, and calculation of the mean year using Buys-Ballot tables. The NDVI showed a unimodal pattern, with a maximum of 0.64 (95% CI ± 0.037) and interannual variability between 0.50 and 0.82. Maximum greenness occurred on March 22, coinciding with the phase of greatest vegetative vigor, and the lowest value (0.20) was reported on October 24. The results provide useful information for optimizing fertilization schedules, health management, and crop estimation. This study is the first characterization based on more than two decades of MODIS data for maize farming in the parish of Colonche.

Palabras clave : mean year; NDVI; remote sensing; vegetation dynamics.