Mangrove Blue Carbon, Coastal Biogeochemistry, and Ecosystem Resilience: A ComparativeAnalysis of Tropical Deltaic and Island Mangrove Systems

Abstract

Mangrove ecosystems are among the most carbon-dense coastal environments, yet their capacity to store carbon and sustain ecological resilience varies strongly across geomorphic, hydrological, and anthropogenic contexts. This study examines how tropical deltaic and island mangrove systems differ in blue carbon accumulation, sediment biogeochemistry, biodiversity function, and vulnerability to climate and land-use pressures. The article argues that mangrove carbon storage cannot be explained solely by vegetation biomass because sediment accretion, tidal exchange, salinity gradients, root architecture, microbial decomposition, and disturbance regimes jointly regulate long-term carbon persistence. Using comparative environmental analysis, coastal biogeochemistry synthesis, remote-sensing evidence, peer-reviewed mangrove carbon literature, and international climate and biodiversity reports, the study evaluates deltaic mangroves and island mangroves as contrasting but complementary coastal systems. The findings indicate that deltaic mangroves often exhibit high sediment carbon accumulation due to riverine sediment supply and organic matter burial, but are vulnerable to upstream damming, conversion, pollution, and subsidence. Island mangroves may exhibit lower sediment input but stronger dependence on tidal exchange, carbonate dynamics, salinity regulation, and reef–seagrass connectivity. This article contributes to natural sciences scholarship by integrating coastal geomorphology, soil biogeochemistry, plant ecology, climate mitigation science, and sustainability-oriented conservation into a unified framework for understanding mangrove blue carbon resilience.