2018 article
Tidal Marsh Creation
COASTAL WETLANDS: AN INTEGRATED ECOSYSTEM APPROACH, 2ND EDITION, pp. 789–816.
Salt and brackish water tidal marshes are productive wetlands that provide ecosystem services including habitat, food energy for the estuarine food web, maintenance of water quality, storage of storm water, buffering storm waves and reducing shoreline erosion, carbon sequestration, and socioeconomic benefits. Loss of tidal marshes occurs as a result of dredging, filling, tidal restrictions, subsidence, sea level rise, and erosion. To mitigate those losses, techniques have been developed to create marshes on sites where they did not previously exist. The goal of tidal marsh creation is to provide habitats similar in structure and function to natural marshes. Because tides are the controlling abiotic factor of tidal marshes, the most critical requirement for creating new marshes is constructing sites at the correct elevation relative to the local tidal regime. Other important site-related factors that must be considered to insure successful marsh creation are slope, drainage, wave climate, currents, salinity, and soil physicochemical properties. Cultural practices that are important to establishment of vegetation include selection of native plant species, seed collection and storage, seedling production, site preparation, soil testing, fertilization, handling of transplants, timing of planting, plant spacing, control of undesirable invasive plants, and maintenance until the marsh is self-sustaining. The criteria used to define successful tidal marsh creation are often controversial. Plant communities may be equivalent to natural reference marshes in a few years, whereas other characteristics, such as soil organic matter, and numbers and species of benthic invertebrates require much longer to reach equivalence. When marsh creation technology is properly applied, tidal marshes can be created that provide many of the same ecosystems services that are provided by natural systems.