Aboveground mangrove carbon stock mapping using WorldView-2 imagery

Mangrove ecosystems have a significant role in absorbing carbon emissions in the atmosphere used as photosynthetic materials. Absorbed carbon emission is stored in the form of biomass in vegetation, of which 47 of the biomass is aboveground carbon stock (AGC). Monitoring the AGC needs to be carried out efficiently, consistently, and sustainably to increase efforts to prevent global warming, and remote sensing imagery has the potentials to address this issue. This study aims to (1) explore the relationship between the selected vegetation indices derived from the WorldView-2 image and the corresponding AGC measurement in the field and (2) estimate and map the spatial distribution of AGC of mangroves. This research was conducted in a mangrove forest in Clungup Mangrove Conservation area, East Java Province, Indonesia. We applied allometric equations to determine the value of vegetation biomass in the study area based on the tree diameter at breast height (DBH), which will then be converted into carbon stock value. For AGC estimation and mapping purposes, we used Normalized Difference Vegetation Index (NDVI), Simple Ratio (SR), Rededge Simple Ratio (SRre), and Combined Mangrove Recognition Index (CMRI). We used correlation and regression analysis to evaluate the statistical relationship between these vegetation indices and field AGC data. Our findings suggested that the SR has the highest accuracy in modeling AGC with an R2 value of 0.124. Thus, it results in a range of AGC from 0.127 tons/pixel to 0.414 tons/pixel in the study site. © 2021 SPIE.