What is the primary role of decomposers in an ecosystem?

Decomposers play a vital role in ecosystems by breaking down dead organic matter, which is essential for nutrient recycling. When plants and animals die, their bodies are composed mainly of complex organic compounds. Decomposers, such as bacteria and fungi, enzymatically convert these complex substances into simpler forms. This breakdown process releases nutrients—such as nitrogen, phosphorus, and potassium—back into the soil, making them available for uptake by plants.

This nutrient release is critical for the health of the ecosystem, as it supports plant growth and maintains soil fertility.

While enhancing soil fertility is a consequence of their activity, it is not the primary role of decomposers; rather, it's the breakdown of dead organic matter that directly leads to this effect. Producing organic matter and increasing photosynthesis are unrelated to the direct function of decomposers in the ecological cycle, as these processes are primarily carried out by producers, like plants.