What defines the area of a river prone to flooding and water saturation?

The area of a river that is prone to flooding and water saturation is defined as a floodplain. Floodplains are flat areas adjacent to rivers that are formed by sediment deposited during floods. These areas are periodically inundated with water, which enriches the soil, making it fertile and suitable for agriculture. The natural flood cycle of a river creates these expansive and often rich ecosystems that are integral for biodiversity.

Wetlands, while they do involve areas saturated with water and can occur in various environments, are not exclusively linked to rivers and their flood cycles. They can exist independently or in relation to other water bodies. Bogs, a specific type of wetland characterized by acidic waters and peat deposition, are not created by flooding rivers and are not as relevant in the context of river dynamics. Deltas, formed at the mouths of rivers where they deposit sediment as they enter a standing body of water, are also distinct from the floodplain concept as they represent a transitional area between river and ocean rather than an area primarily affected by flooding events.