Bacteria helps to maintain the health of ecosystems by breaking down dead matter and cycling nutrients into usable forms. Bacteria live in all environments, and provide most of the oxygen on Earth.
Bacteria are decomposers that break down organic materials in the soil. For instance, bacteria help to decompose dead matter, such as fallen trees, into usable nutrients for living organisms within the ecosystem. The result of decomposing dead matter results in richer soil that is able to support diverse ecosystems.
Bacteria cycles nutrients, including nitrogen and carbon, to transform the nutrients into usable forms. For example, bacteria transform carbon into carbon dioxide, which is necessary for photosynthesis, the process which allows plants to produce energy from light. Without bacteria, primary producers would cease to survive. Oxygen production is a direct result of bacterial activity. For instance, cyanobacteria, a bacteria that is present in oceans, produces a significant amount of the oxygen available on Earth.
Bacteria transforms nitrogen into nitrates or nitrites, which are forms of nitrogen that plants can use to grow. Some plants, such as beans, store nitrogen-producing bacteria in their root systems to ensure proper growth. Bacteria also live inside animals, and are used by those animals to break down food into usable nutrients. For example, cows and giraffes use bacteria in the stomach to break down plant matter so that the food is more easily digested, allowing the animals to eat low-quality foods to survive.