How do bacteria contribute to nutrient cycling?

Bacteria play a crucial role in nutrient cycling primarily through their ability to decompose organic matter. When organisms die or when plant materials fall to the ground, bacteria break down these complex organic compounds into simpler substances. This decomposition process releases nutrients, such as nitrogen, phosphorus, and carbon, back into the soil and the ecosystem. These nutrients are then available for uptake by plants, which in turn are consumed by herbivores and form the basis of most food webs.

Additionally, bacteria assist in various biochemical processes, such as nitrogen fixation and nitrification, which are vital for replenishing soil nutrients. Thus, their role in decomposing organic matter is essential for maintaining the balance of ecosystems, making option C the most accurate choice regarding how bacteria contribute to nutrient cycling.