Wetlands in the Tidal Freshwater Zone

Abstract

Tidal freshwater wetlands occur in the upper part of estuaries in Europe and North America (and likely elsewhere) and experience tides of up to several meters in amplitude twice a day. They occur at the interface between the brackish zone in the estuary and the river; and where brackish and fresh water mix is an area of maximum suspended matter (i.e., the maximum turbidity zone). The tidal freshwater zone within the estuary plays an important role in overall patterns of nutrient cycling for the whole estuary and the pattern appears to differ in the brackish and saline sections. Although tidal freshwater wetlands do not include many endemic or restricted species, they are characterized by high species and habitat diversity. There is distinct zonation in flora and fauna species, responding to the relationship between surface elevation and tidal amplitude. The dominant species are different between Europe and North America, but the structure of the system and the life strategy of the species are fully comparable. The tidal freshwater wetlands in Europe and North America also have a common history of being highly influenced by human activities, resulting in altered hydrology, losses in wetland area, and high levels of sediment and nutrient input on both sides of the Atlantic Ocean. In recent years, restoration and preservation activities have also been initiated on both sides of the Atlantic and there is hope that tidal freshwater wetlands will increasingly become important elements of estuarine systems that provide many free ecological services to man and nature.KeywordsSeed BankTidal FreshwaterTidal WetlandTidal Freshwater MarshTidal Freshwater WetlandThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.