Trophic niche

It has been recognized for some time that fluids in motion, such as the atmosphere or the ocean, disperse added materials. This properly has been exploited by engineers in a variety of ways, such as the use of smoke stacks for boiler furnaces and ocean ontfalls for the release of treated wastewaters. It is now known that dilution is seldom the solution to an enviromnental problem the dispersed pollutants may accumulate to undesirable levels in certain niches in an ecosystem, be transformed by biological and photochemical processes to other pollntants, or have nnanticipated health or ecological effects even at highly dilute concentrations. It is therefore necessary to rmderstand the transport and transformation of chemicals in the natural environment and through the trophic chain ctrlminating in man. 

One of the factors supporting the use of algae and invertebrates in the bioassays is their niche in aquatic ecosystems. If these organisms are adversely affected by a toxicant, then the surrounding ecosystem may also feel the effects, either directly or indirectly, from the lack of a food source. Algae and invertebrates occupy low trophic levels, and their disturbance may exhibit a chain effect throughout the ecosystem. 

Lee, j. j. Muller, W. a. 1973. Trophic dynamics and niches of salt marsh foraminifera. American Zoologist, 15, 215-223. 

Element concentrations (Cd, Pb) in fish muscle at the same location (lake) differ between different species and individuals due to species-specific capacity to regulate of accumulate trace metals (Otchere 2003). Different individuals in the same community at the same trophic level could accumulate heavy metals differently due to differences in habitat/niche s physical and chemical properties. 

---