In tropical rain forests, such as the Amazon in South America, decomposer organisms include certain species of worm, fungi, bacteria and small arthropods. Decomposers are also known as saprotrophs and obtain nutrients by feeding off of dead and decaying materials. They play an important role in enriching soil and promoting the growth of living plants and animals by increasing levels of certain nutrients, such as nitrogen.
Creatures such as the velvet worm are organisms that live on the forest floor and feed off small invertebrates. Earthworms are another example of a tropical decomposer and feed off fallen leaves and tree bark.
Unlike worms, fungi are decomposers that can be found both on the forest floor as well as on the trunks of trees. Tropical fungi feed on decaying plant matter and are typically clustered into groups connected by an extensive root system.
Saprophytic bacteria are typically found ubiquitously in nutrient-rich soils. High numbers of these bacteria are found in tropical forests, with over 40 million bacteria residing in each gram of soil. These microscopic organisms feed on both dead plant and animal matter.
Arthropods, such as termites and ants, are common decomposers that, like fungi, can be found both on the forest floor and on trees. Termites specifically eat wood, while ants eat animals and fungi.