Tue March 16, 2010 By: Annette Parakkal

Answer :

Expert Reply
Wed March 17, 2010

Energy is captured by producers, then passes through consumers, finally ends up the fodder for decomposers, and all the while is continuously lost as heat, a product of the inefficiencies of biochemical reactions.

The first trophic level consists of producers, the second trophic level consists of primary consumers. The next trophic level are secondary consumers followed by tertiary consumers. Scavengers and decomposers are two other important kinds of organisms, located at the base of every food web.

Scavengers are essentially garbage collectors, feeding on others’ leftovers and bits of dead organisms. Decomposers break down nonliving organic matter into nutrients that can then reenter the food web, beginning the cycle of energy all over again. Scavengers are a part of the detrital food web of ecosystem.

The valuable ecological service of recycling of dead biomass is not just performed by scavengers—other detritivores such as bacteria, and fungi are also important, and in fact are largely responsible for the final stages of the decomposition and humification processScavengers provide a very important ecological service, because they help to rapidly reduce dead animals and plants to simpler constituents, and thereby prevent an excessive accumulation of dead biomass. Excessive accumulations of dead plants can also bind up much of the nutrient capital of ecosystems, so that not enough is recycled for use by living plants, and ecosystem productivity becomes constrained by nutrient limitations.

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