Mangroves in the Anthropocene: A global synthesis of carbon storage, biodiversity, and coastal resilience under climate and anthropogenic stressors

Mangrove ecosystems play a pivotal role in global carbon storage, biodiversity maintenance, and coastal resilience, yet research remains fragmented, often isolating these functions rather than examining their interconnections. Critical gaps persist regarding spatial variability in carbon stocks, the functional role of biodiversity, and the long-term resilience benefits of mangroves under climate change and anthropogenic pressures. This systematic review synthesizes global evidence from 2000 to 2024, integrating carbon dynamics, biodiversity functions, and resilience attributes of mangrove ecosystems. Unlike previous reviews, this study adopts a distinctive mixed-methods framework that integrates quantitative scientometric analysis with qualitative synthesis of carbon sequestration parameters, biodiversity indicators, and vulnerability evaluations. Literature was sourced primarily from Scopus using targeted search strings ("mangrove," "carbon sequestration," "biodiversity," "coastal resilience"), with screening guided by the PRISMA framework. From over 2300 initial records, 1356 peer-reviewed articles were analyzed using Biblioshiny (R package) and VOSviewer to map research trends, collaboration networks, and thematic clusters, revealing an exponential growth in publications post-2015. Results indicate that mangroves sequester carbon at a mean rate of 174 g C m^-2 yr^-1 (range: 95-235 g C m^-2 yr^-1), with total carbon stocks reaching up to 1745 Mg C ha^-1, surpassing many terrestrial forests. The Pacific and Southeast Asian regions exhibit the highest carbon densities. Mangrove biodiversity, supporting over 2000 species, underpins essential ecological functions including nutrient cycling, soil accretion, and carbon retention. Additionally, mangroves provide coastal protection for more than 150 million people by stabilizing shorelines and reducing erosion. Restoration could recover an estimated 390 million metric tons of CO₂ equivalent, underscoring its potential for climate mitigation. However, accelerating habitat loss, human pressures, and insufficient policy enforcement threaten their sustainability. This synthesis emphasizes the urgent need for integrated, cross-disciplinary conservation frameworks that unite carbon, biodiversity, and resilience perspectives to enhance climate adaptation and inform evidence-based policy.