Restoration of an Impounded Salt Marsh in New England

Increased Variability of Microbial Communities in Restored Salt Marshes nearly 30 Years After Tidal Flow Restoration

“…(Sinicrope et al 1990). Many of the 115 macroinvertebrate populations also appear to be recovering and are similar to populations in 116 adjacent unimpounded reference marshes (Swamy et al 2002).…”

Comparison of nekton use of Phragmites australis and Spartina alterniflora marshes in the Chesapeake Bay, USA

“…Although salt-marsh loss by natural processes such as erosion (Wray et al 1995, Meyer et al 1997) and sea-level change (Webb et al 1995) is inevitable, additional loss or alteration due to direct and indirect human impact occurs (Sinicrope et al 1990, Havens et al 1997. While the physical alteration of marsh habitat is considered an immediate threat, the progressive change through indirect influences on the estuarine environment (such as water quality, water circulation impediments, freshwater runoff, etc.)…”

“…Throughout the eastern USA, the dominant floral composition of many salt-marsh systems is threatened by alteration. Invasive species including reed grass (Phragmites australis) may invade wetlands, spread, and reduce openwater habitat (Caffrey 1996, Broyer & Varagnat 1998, and/or replace dominant macrophyte species through natural habitat (Sinicrope et al 1990, Havens et al 1997 or anthropogenically derived (Rice 1996, Havens et al 1997 disturbances. Substantial declines in Spartina alterniflora areal coverage have occurred in the USA due to encroachment into mesohaline estuarine areas by P. australis (Rice 1996, Havens et al 1997), a species typically thought to be native to oligohaline wetlands, including those of North America (Niering & Warren 1977, Orson et al 1987.…”

Microbial response to salt marsh restoration

“…The additional environmental changes in the sediments of the P. australis and Typha marsh sediments, which were consistently in the direction of the reference marshes, further suggests a trajectory toward recovery in these previously degraded systems, a trajectory that is consistent with similar restorations throughout New England (Sinicrope et al 1990;Warren et al 2002;Smith et al 2009). Other work has shown that P. australis invasion into salt marshes increases organic matter and carbon content, but, consistent with our findings, both organic matter and carbon content decreased in the restored marsh in that study (Uddin and Robinson 2017).…”

“…The most common indicator of restoration success is the response of macro-organisms, particularly the return of native vegetation, although it may take decades to establish the full complement of salt marsh diversity (Warren et al 2002). In successful restorations of New England salt marshes, the expansion of native vegetation occurs at rates of approximately 5% per year (Sinicrope et al 1990;Warren et al 2002). Freshwater and upland taxa often dieback immediately after exposure to increased seawater inundation, leaving space for native salt marsh vegetation to spread (Smith and Warren 2012), yet a return of native vegetation is not always indicative of a return of full ecosystem function and services (Elphick et al 2015).…”