Soil bacteria and soil fungi are the start of the soil food web that supports other soil organisms and the functions of a healthy soil. Diverse populations of soil bacteria and fungi can suppress root diseases. Soil bacteria and fungi are encouraged by ground cover and organic matter inputs. Fungi and bacteria are the key decomposers in many ecosystems; they use the chemical energy in dead matter and wastes to fuel their metabolic processes. Other decomposers are detritivores detritus eaters or debris eaters. These are usually multicellular animals such as earthworms, crabs, slugs, or vultures. They perform a valuable service as Earth's cleanup crew. Without decomposers, dead leaves, dead insects, and dead animals would pile up everywhere. Imagine what the world would look like! More importantly, decomposers make vital nutrients available to an ecosystem's primary producers usually plants and algae.