Ecological responses to tidal restorations of two northern New England salt marshes

摘要: Efforts are underway to restore tidal flow in New England salt marshes that were negatively impacted by restrictions. We evaluated a planned restoration at Mill Brook Marsh (New Hampshire) and Drakes Island (Maine) where partial inadvertently occurred. Salt marsh functions both determine the impacts from restriction responses following restoration. Physical biological indicators of (tidal range, surface elevations, soil water levels salinities, plant cover, fish use) measured compared those nonimpounded reference sites. Common restrictions sites were: loss flooding, declines elevation, reduced salinity, replacement vegetation fresh brackish plants, use marsh. Water levels, salinities increased immediately Salt-intolerant was killed within months. After two years, mildly salt-tolerant had been largely replaced several species characteristic high low marshes. Eight years after unplanned, Marsh, dominated bySpartina alterniflora, habitat. Hydrologic allowed for unrestricted saltwater exchange restored relatively quickly comparison Island, full not achieved. The irregular regime resulted cover patterns dissimilar used as reference. proper hydrologic (flooding height, duration frequency) is essential promote rapid recovery functions. predict functional will be quick Brook, but believe habitat become equivalent unless hydrology further modified.