An expression of the flow of energy through various communities
of organisms in ecosystems, typically consisting of four or more trophic
levels. Food webs dissipate energy, spreading it out laterally to communities
of organisms living at the same trophic level. Most stream and river
ecosystems are comprised of food webs, not food chains. For example,
sunlight, in-stream macrophytes, macro invertebrates, trout and other
insect-eating fishes, predators of trout. Many macro invertebrate and
fish species feed on in-stream insects, thus taking away from the flow
of energy towards the top trophic levels.
Links
