Which plant type is characterized by a strict dependence on sediment for stability?

The plant type characterized by a strict dependence on sediment for stability is rooted-floating. These plants have their roots anchored in the sediment on the bottom of a body of water, which allows them to receive nutrients directly from the substrate while also allowing their leaves and stems to float on the surface of the water. This anchoring provides stability and support, enabling them to thrive in aquatic environments.

In contrast, free-floating plants do not anchor themselves to the sediment; instead, they float on the water surface, relying on buoyancy to remain afloat. Emersed plants grow partially above the water and are often rooted in moist soil but may not depend on sediment in the same way as rooted-floating plants. Submersed plants are fully underwater and can be anchored in sediment, but they do not have the same floating structures that define rooted-floating plants. Thus, the reliance on sediment for stability distinctly identifies rooted-floating plants.