From Tides to Traits: A Bottom-Up Perspective on the Potential Competitive Advantage of Exotic over Native Mangroves

Abstract

Mangrove ecosystems are increasingly exposed to climate-driven changes, including shifts in tides, freshwater inputs, and coastal flooding, which may affect both native and exotic species. Mangrove ecosystems, including their associated microbiomes, plant traits, and overall ecosystem function, have been widely studied. However, the mechanisms linking tidal dynamics to plant traits and performance remain poorly understood. Here, we propose a perspective in which tidal inundation is linked to hydrological changes that alter sediment conditions, rhizosphere processes, nutrient cycling, and plant functional traits. We discuss how changes in tidal inundation alter sediment physicochemical conditions, particularly salinity and redox potential, which may reshape microbial community composition and regulate key biogeochemical processes, including carbon decomposition, nitrogen and phosphorus cycling, iron reduction, and sulfate reduction. These processes influence nutrient availability and plant nutrient acquisition, with their effect likely mediated by root functional traits, phenotypic plasticity, and stress tolerance shaping overall plant performance. We propose that native and exotic mangroves may differ in their functional traits and rhizosphere associations potentially conferring a competitive advantage on exotic species through more efficient resource acquisition and utilization under specific environmental conditions. However, whether tidal and rhizosphere processes consistently favor exotic mangroves remains unresolved. We therefore conceptualize mangrove adaptation as an emergent outcome of interactions among hydrology, sediments–rhizosphere–microbial processes, nutrient dynamics, and plant functional traits, providing an integrative framework for understanding native–exotic interactions and guiding mangrove restoration under global environmental change.