Final answer:
Floodplains are areas next to rivers that flood and have nutrient-rich soil. They provide benefits such as water storage and habitat creation. Floodplains get nutrient-rich soil through annual flooding events.
Step-by-step explanation:
Floodplains are areas of land that are adjacent to a river or stream and are subject to flooding during periods of high water flow. They are typically flat and can stretch out for miles on either side of the river.
Some benefits of floodplains include: storing excess water from floods, slowing down runoff to prevent erosion, removing excess nutrients from runoff, providing a unique habitat for certain plant and animal species, and supporting high biodiversity.
Floodplains get nutrient-rich soil through annual flooding events. When rivers flood, they deposit sediments and organic matter onto the floodplain, enriching the soil with nutrients. This process is similar to how the Nile River in North Africa and the Tigris and Euphrates rivers in the Middle East contribute to the nutrient-rich soil of their floodplain areas.