Flood plain riparian forest zone
This natural community occurs along rivers and streams. It consists of:
Bottomland and Floodplain(Alluvial) Forests: flat, low-lying areas beyond the stream channel that flood at least occasionally. Sediments from the floodwaters (called "alluvium"), often nutrient-rich, settle in these areas. Often called "alluvial forests", they are close to the water table. Seepage wetlands are often embedded within them. Plants are adapted to shady, soggy, low oxygen conditions. The topography, shaped by floods, varies greatly, with hummocks that are nearly mesic, and depressional areas that temporarily hold water.
Riparian zone - the land along the river channel, and islands within the river. This zone is flooded often. Some stream sides are rocky, with plants rooted among the boulders, while others consist of easily eroded sediments. Plants in this zone are adapted to sunnier conditions and can withstand the force of floodwaters. Rivers meander in S-shaped patterns. The outer side of the meanders form cutbanks, where erosion is occurring, while the inner sides form pointbars: river bars that pioneer plants colonize.
What's special: The high nutrient levels and moisture foster rich, lush vegetation layers, with many food and shelter resources. This variety of habitats supports a diversity of amphibians, birds and stream-side mammals. These communities also keep water resources clean by stabilizing stream banks and absorbing rainwater, creating buffers.
Indicator species: Box elder, river birch, green ash, sycamore, overcup oak, black willow
Related communities: High areas in the bottomlands, and those farthest from the flood zone grade into Mesic Forests. Seepage Wetlands are often embedded and grade into Wet Meadows.