Evaluation of salt marsh restoration by means of self-regulating tidal gate – Avon estuary, South Devon, UK

摘要: Abstract Salt marshes provide important regulating ecosystem services, including natural flood defence and carbon sequestration, which adds value to restoration biodiversity offsetting schemes. This study evaluates the success of salt marsh using a Regulated Tidal Exchange (RTE) system in SW England, i.e., self-regulating tidal gate (SRT), controlling partial saline inundation 14-ha area former reclaimed for agriculture 1760. A combination (a) direct hydrodynamic monitoring water sediment flux (b) repeat surveys evaluate morphological ecological (plants foraminifera) changes over 5-year period, was implemented immediately following SRT commissioning. Morphological were limited proximity due influx yielding sedimentation rates that an order magnitude below nearby marsh. Ecological change ephemeral community only detected after 5 years cycles, with delayed response attributed initial conservative settings, followed by excessive rainfall recurring failure open position, (c) lack propagule supply caused & relatively narrow inlet pipe used system. While under optimum settings encouraging, perennial plants foraminifera abundance demonstrated far from reaching status. We surmise this is primarily being more rapid than drainage leading submergence during cycle. Our shows design schemes requires synergistic understanding core geomorphological approaches assess viability success. conclude can be useful technique intertidal habitat creation where there are significant site constraints (especially risk), but we need realistic our expectations what it achieve terms delivering community.