Late Holocene salt marsh development under a regime of rapid relative-sea-level rise: Chezzetcook Inlet, Nova Scotia. Implications for the interpretation of palaeomarsh sequences
Pollen data illustrating a 2000-year record of salt marsh development have been obtained from a variety of outer-estuarine settings in close proximity to the present gravel-dominated coastal barriers at Chezzetcook Inlet, Nova Scotia. The relationship between the biostratigraphic and lithostratigraphic data and relative-sea-level movement is complex. In the outer estuary, temporal and spatial changes to the floral and sedimentological composition of the salt marsh reflect principally processes of estuarine and back-barrier sedimentation that resulted in steep environmental gradients and the development of regressive marsh–sediment complexes, despite a relative-sea-level rise of up to 3.8 mm/a during the late Holocene. Our results contrast with those from the inner estuary at Chezzetcook Inlet, where salt marsh has developed only over the last 200 years as a result of sediment inwash due to European land use, and followed a prolonged episode (approx. 5000 years) of tidal flat conditions. This contrast high...