Above: PlanetScope image of salt marshes study site in Saeftinghe, Netherlands taken April 24, 2022.
Coastal wetlands, including river deltas, estuaries, coastal lagoons and open coasts, consist of important ecosystems, like mangroves and salt marshes. These areas are home to vast amounts of biodiversity, and they support critical ecosystem services, protecting coastal communities from waves and storms. However, there are distinct spatial differences in the channel networks – areas where the water carves its way through the vegetation – between mangroves and salt marshes. These differences determine the systems’ ability to generate habitats for plant and animal species and support coastal protection. Using PlanetScope data, researchers from Utrecht University in the Netherlands and the University of Exeter in the United Kingdom evaluated the spatial patterns of tidal channel networks of both mangroves and salt marshes from around the world, and investigated recruitment strategies – the vegetative seed dispersal and growth process – of each ecosystem in a simultaneous experiment. The researchers compared PlanetScope imagery from fifteen study sites varying in tidal range, and they concluded that salt marshes are dissected by more extensive channel networks than mangrove systems. These features in salt marshes can better support wetland resilience and storm protection. They further suggested that the recruitment strategies of salt marshes better facilitate this channel development compared to the recruitment strategies of mangroves. “Insights of our study are crucial to understand wetland resilience with rising sea-levels especially under climate-driven ecotone shifts,” said the authors.
The full study can be found in Nature Communications.