'Saltmarsh absorbs wave energy, providing long term natural protection from erosion and new wetland habitats on a massive scale. The developing marsh, with shifting channels and creeks, also provides a vital refuge for wetland wildlife and is an important nursery for fish.'
I visited the Steart Marshes a couple of weeks ago, and I spent a lovely day walking beside the Parrett Estuary and seeing plenty of healthy birdlife that was clearly benefitting from the freshly created habitat. Where a breach has been cut through the sea defences, lagoons have been formed which have rapidly silted up and which have certainly become salt marsh habitat.
However the breach is on the landward side of the peninsula, and exactly how it is going to provide long term natural protection from erosion remains unclear to me. Meanwhile, the natural succession to freshwater marsh appears to be actively prevented by artificially keeping the salt marsh completely separate from nearby fresh water marshes.
Nevertheless it's an interesting experiment, and appears to make the best of the modern requirement that recipients of public money, including nature reserves, have to follow a pre-conceived design and then stay the way they have been designed. This isn't natural, but it is still worth a visit.