The bottom habitat of a lotic environment is the streambed. In some conditions, this habitat can extend across the entire width of the bed. In deeper channels with sloped edges, zonation may create a littoral or edge habitat. In shallow channels or low water conditions, the streambed can be exposed intermittently.

The streambed can comprise a variety of physical and organic materials and can be either an eroding basin or a depositional environment. These situations can alternate in the same stream, as may be seen in riffles or ponds.

In slow-moving streams, there is an abundance of invertebrates, especially aquatic insects. Vegetation is generally absent from the bottom habitat, except along the stream bank. In fast-moving streams, algae, mosses and liverworts and some specially adapted flowering plants can adhere to rock surfaces or root firmly in the gravel bottom. Aquatic animals are also well adapted to withstand fast current and seasonal variations in water level.

This Document Includes:

Formation
Physical Aspects
Ecosystem
Successional Sequence
Plants
Animals
Special Features
Distribution

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Additional Keywords:
hydrosere, diatoms, algae, liverworts, Fountain Moss, bur reed, pondweed, Threadfoot, blackfly, dragonfly, mayfly, stonefly, caddisfly, waterbugs, water beetles, crustaceans, rotifers, nematodes, protozoans, leeches worms, molluscs, sponges, ectoprocts, newts, tadpoles, mussels, White Sucker, American Eel, Bullhead Catfish

Associated Topics:

T8.1 Freshwater Hydrology
T8.2 Freshwater Environments
T11.5 Freshwater Wetland Birds and Waterfowl
T11.11 Small Mammals
T11.13 Freshwater Fishes
T11.15 Amphibians and Reptiles
T11.16 Land and Freshwater Invertebrates

Associated Habitats:

H3.1 Open-water Lotic (Rivers and Streams)
H3.4 Bottom Lentic (Lakes and Ponds)
H3.5 Water's Edge Lotic (Rivers and Streams)