Precision in mapping and assessing mangrove Biomass: Insights from the Persian Gulf coasts

Abstract

This groundbreaking research makes a contribution to climate change adaptation studies by filling a crucial knowledge gap related to the precise evaluation of mangrove biomass—an essential element influencing the future trends of coastal ecosystems. Specifically, the study concentrates on the Hara Biosphere Reserve (HBR) on the coasts of the Persian Gulf (PG), aiming to generate precise maps of mangrove biomass. The methodological approach involves a comprehensive analysis, including the utilization of Landsat imagery to establish an NDVI map of mangroves, the application of the Cumulative Sum (CUSUM) method to determine a threshold NDVI value for distinguishing between tall and dwarf mangroves, and the subsequent mapping of their distribution in both coastal and island zones. Additionally, the study calculates above-ground biomass (AGB) and below-ground biomass (BGB) values in sample plots, develops a regression relationship between biomass and NDVI values, and integrates maps of tall and dwarf mangrove extent with spatial variations in AGB and BGB. Noteworthy outcomes include the identification of a threshold NDVI value (0.63) for distinguishing mangrove types and revealing distinct biomass values for mangroves in both coastal and island zones. Significantly, tall mangroves positioned on the seaward edges exhibit higher biomass in both zones than dwarf mangroves. These findings shed light on the potential exacerbation of climate change impacts, such as rising sea levels and changing tidal range on mangroves of the coasts of the PG due to the heightened productivity and specific spatial distribution of tall mangroves. Recognizing these structural characteristics and production disparities is crucial for developing effective climate change adaptation programs. Integrating such insights into management strategies is emphasized as pivotal for enhancing the efficiency and success of these programs, presenting a robust solution for protecting mangroves in diverse coastal areas.