In an ecosystem with four levels-producers, primary consumers, and two higher level consumers-describe where the decomposers operate within the context of these trophhic levels.

Decomposers can break down any dead organic matter. Since any of the organic matter consume can come from any level, there isn't a specific place for decomposers. It is hard to place them because as you travel up the food pyramid energy is lost. Decomposers would have their own level because of this.

compost can be added to topsoil as a:

pesticide