Salt marsh macrofauna: An overview of functions and services

Salt marshes are globally important blue carbon ecosystems, providing essential services such as coastal protection, carbon sequestration, nutrient cycling, and biodiversity support. Among their key inhabitants, macrofauna play critical roles in sustaining ecosystem health and resilience through processes like bioturbation, nutrient cycling, organic matter turnover, and trophic interactions, which in turn support ecosystem services such as fisheries and coastal community livelihoods. Despite their contributions, no comprehensive review has yet focused exclusively on the diverse roles and services of salt marsh macrofauna. This review aims to address this gap by synthesizing current research, supported by a bibliometric analysis revealing significant growth in studies since the year 2000, especially those addressing ecosystem services and climate resilience. We provide an in-depth assessment of macrofaunal functions in bioturbation, nutrient cycling, organic matter dynamics, greenhouse gas regulation, primary and secondary production, and food web interactions. Additionally, we examine the ecosystem services provided, such as provisioning, regulating, and cultural services, and explore the impact of environmental stressors on macrofaunal communities. Finally, this review identifies significant knowledge gaps, offering strategic insights for future research and serving as a vital reference for advancing coastal management and salt marsh conservation strategies.