1 INTRODUCTION Tidal marsh ecosystems are vegetated coastal wetlands located in areas of regular to occasional tidal inundation, formed by a broad variety of herbaceous and woody vascular plants (Adam, 2002). Whilst dominated by saline and brackish marshes, they include areas of freshwater tidal marsh (Barendregt, 2018; Mitsch & Gosselink, 2015). They occur along many of the world's sheltered, sediment-dominated coastlines, particularly in temperate and arctic regions (Tiner & Milton, 2018).
