Coastal wetlands can be saved from sea level rise by recreating past tidal regimes
Coastal tidal wetlands have the ability to remove significant amounts of carbon from the atmosphere and accumulate them in the sediment, helping to mitigate climate change. Along with their water and soil purification capabilities, it can be understood why it is vital to preserve and restore these wetlands worldwide from the negative impacts of sea level rise.
Coastal tidal wetlands, such as saltmarsh and mangrove wetlands, can be found in the tidal zone between the land and ocean. These vegetated intertidal ecosystems are valuable ecological environments that serve as important habitat for wildlife; in addition to providing numerous ecosystem benefits for humans. Globally, 50% of these wetlands have been disturbed or damaged by human impact since 1900 and projections indicate up to 30% of current global wetlands could be lost due to sea level rise by 2100.
The United Nations declared 2021-2030, the Decade on Ecosystem Restoration calling upon nations and governments to take action to restore damaged ecosystems. To support this important initiative UNSW EcoEng researchers from the Water Research Laboratory have developed a sustainable solution that demonstrates the ability to preserve existing coastal wetlands from sea level rise threat and restore wetlands already influenced by human intervention. We call our solution the “Tidal Replicate Method”!
UNSW’s “Tidal Replicate Method” creates a regime that mimics the desired tidal inundation duration and depth for intertidal wetlands. This synthetic tidal regime can then be applied via automated control systems, called “SmartGates”, which can be applied to any tidal wetland in the world regardless of size, depending on the wetland geometry and boundary conditions.
This method can save millions of hectares of coastal wetlands worldwide from permanent inundation. Our analysis of global Ramsar wetlands, (wetlands of international importance), show that the “Tidal Replicate Method” can be implemented at 32 Ramsar listed wetlands sites located across six continents. This has the potential to save over 1,840,000 hectares of high priority wetlands from permanent inundation due to sea level rise; with the potential to save $230 billion USD per year on ecosystem services.
A journal article on the "Tidal Replicate Method" can be accessed here: https://www.nature.com/articles/s41598-021-80977-3