Predicting sediment flow in coastal vegetation
Seagrass, kelp beds, mangroves, and other aquatic vegetation are often considered “ecosystem engineers” for their ability to essentially create their own habitats: Aquatic leaves and reeds slow the flow of water, encouraging sediments to settle nearby to form a foundation on which more plants can grow. Such underwater forests provide shelter to hundreds of organisms, and can also protect shorelines from erosion. However, in the last few decades, large swaths of aquatic vegetation have disappeared around the world, including 100 million acres of wetlands, and thousands of acres of seagrass and kelp beds, in the United States. In large part, sediment transport — how sediment flows through a region — determines the survival of coastal marshes and mangroves: Plant growth depends on the accumulation of sediment to the seafloor. When strong storms or currents carry sediment away, underwater forests can also wash away, exposing coastlines and riverbanks to erosion. Now researchers at MIT...