Riparian zones are nutrient sinks in low order areas, the nutrients are deposited into the sediment layer. Riparian zones are nutrient transformers in high order areas because of all of the aerobic and anaerobic activity. Riparian zones have a high water table because of their proximity to a river or stream. The plants in this zone have their roots into the saturated zone. Odum called riparian zones the interface between mans most viable resource, water, and his living space, the land.
Riparian zones are of great historical importance.
Much of human civilization has been and is conducted in riparian areas. Riparian zones are ecotones between aquatic and upland systems, meaning that there is a continuous exchange of energy, species, and nutrients. In the eastern US riparian zones can be 10 km wide, while in the west they are usually only a couple of meters wide. In bottomlands before European settlement there were 21 million ha, today there are 4.9. The existing bottomlands are found from Virginia to Texas.