Temporal Dynamics of Arid Savannas and Mangroves with MODIS Time Series Analysis

This study explores vegetation indices in arid savannas and mangroves, utilizing MODIS-MYD13Q1 data for Botswana, South Africa, and Henry’s Island, India. The Mangrove Forest Index (MFI), Mangrove Vegetation Index (MVI), and Normalized Difference Vegetation Index (NDVI) are employed to assess vegetation health, detect submerged mangrove forests, and measure mangrove likelihood. While NDVI is effective for arid regions, MFI and MVI yield optimal results for mangroves. Categorizing mangroves into five types, the study tracks seasonal variations through maximum MFI values in Winter (0.23), Summer (0.27), and Monsoon (0.58) over three years. MVI produces values of 4.18 in Summer, 7.14 in Monsoon, and 4.15 in Winter. Results of simple linear regression show a declining trend in NDVI over time, indicated by the negative slope (−3.61 x \(10^{-5}\) ), with highest values during the rainy season in Botswana and lower values in 2015 and 2016. The MFI exhibits a positive slope of \(1.26 \times 10^{-5}\) , indicating an increasing tendency that peaks in spring/summer and dips in autumn/winter.