ABSTRACT
Salt marshes are wetlands dominated by salt-tolerant herbaceous plants (halophytes) that typically develop in depositional environments subject to tidal inundation. We limit discussion to tidally influenced systems because processes associated with hydrology are critical for restoration planning and success. Tidal marshes (hereafter salt marshes) transition from salt to brackish and fresh as fresh water contributions increase. Found along the margins of all continents except Antarctica, salt marshes typically are limited to latitudes greater than 25° and can extend into arctic coastlines. Their abundance and extent at any particular locale depends upon the physical exposure and slope of the shoreline, with extensive marshes along flat trailing edges of continental plates, especially landward of barrier beach systems; whereas narrow, fringing marshes are typically found along steep shorelines (Mitsch and Gosselink 2000; Morgan et al. 2009). Salt marshes embody several ecological functions that are important to humans as ecosystem services, which range from support of coastal food webs and biodiversity to storm protection and carbon storage.
