Mapping of the Spatio-Spectral Dynamics of Mangrove Chlorophyll Concentrations via Sentinel-2 Satellite Imagery

K. K Basheer Ahammed (Department of Marine Science, Faculty of Marine Science and Fisheries, Udayana University, Jimbaran, Bali 80361 Indonesia. International Union for the Conservation of Nature (IUCN), Commission on Ecosystem Management (CEM), South Asia)
I Wayan Gede Astawa Karang (Department of Marine Science, Faculty of Marine Science and Fisheries, Udayana University, Jimbaran, Bali 80361)
I Wayan Nuarsa (Department of Marine Science, Faculty of Marine Science and Fisheries, Udayana University, Jimbaran, Bali 80361)
I Gede Surya Indrawan (Department of Marine Science, Faculty of Marine Science and Fisheries, Udayana University, Jimbaran, Bali 80361)
I Gede Hendrawan (Department of Marine Science, Faculty of Marine Science and Fisheries, Udayana University, Jimbaran, Bali 80361)
Ni Made Nia Bunga Surya Dewi (Doctor of Environmental Science, Post Graduate Program, Udayana University, Jimbaran, Bali)
Arvind Chandra Pandey (Department of Geoinformatics, School of Natural Resource Management, Central University of Jharkhand, Cheri Manatu Rachi, 835 222)

Forum Geografi
Vol. 38 No. 2 (2024): August 2024

Mangrove ecosystems play a critical role in maintaining coastal health; however, they are increasingly threatened by anthropogenic activities and climate change. Health assessment is essential for effective conservation efforts. However, traditional remote sensing techniques such as the normalised difference vegetation index (NDVI) may not fully capture the complex physiological processes influencing vegetation health. Therefore, this study investigated chlorophyll (Chl) dynamics in mangroves using remote sensing techniques, including the NDVI and a novel method, the normalised area over reflectance curve (NAOC), via Sentinel-2 satellite imagery during October 2023, and analysed spatial variations in Chl content (CC) via the Google Earth Engine API. NDVI and NAOC-Chl were weakly correlated (0.47), highlighting their complementary roles. The average NDVI and NOAC-Chl values for different species were analysed, and Rhizophora mucronata presented the highest value (NDVI: 0.86 ± 0.08, NOAC: 20.48 ± 4.49.