Investigate Decomposers and Their HabitatDecomposition stations in your habitat learning lab allow you to observe decomposition over a long period of time and learn how various natural cycles such as the carbon and nitrogen cycles function in nature.
By maintaining a rotting log learning station, compost bin/ pile, or vermicomposting bin, you will learn about a vast array of decomposers (bacteria, fungi, arthropods and worms) as well as organisms that feed on the decomposers (salamanders, arthropods and worms).
Mushrooms on Rotting Log
flickr – The_Gut
Decomposition is the natural process of breaking down dead plants, animals, and other organic matter into smaller pieces and simpler materials. This process is an important part of life on Earth because it returns nutrients to the environment. Plants need nutrients in soil to grow, and decomposition helps make those nutrients available again. Without decomposition, dead plants and animals would pile up, and nutrients would remain trapped in their bodies instead of being recycled through ecosystems.
Think of decomposition as nature’s recycling system. A fallen leaf may be eaten and broken into small pieces by tiny organisms. As the leaf pieces decompose, nutrients are released into the soil, where they can be taken up by plants. Those plants may then become food for animals. When those plants and animals eventually die, decomposition begins the cycle again.
Energy Pyramid Illustrating How Decomposers are Important at Every Level
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There are many organisms that make the process of decomposition happen. Decomposers break down dead plants, animals, and other organic matter, turning complex materials into simpler substances that can return to the soil and water. They are found almost everywhere—from forests and fields to ponds, streams, and even your backyard. Many different kinds of organisms work together to complete the process of decomposition.
Scavengers are animals that feed on dead animals or the remains of animals they did not kill themselves. They help start the decomposition process by removing and consuming large pieces of a dead animal. This leaves smaller pieces and waste that can then be used by detritivores, fungi, bacteria, and other decomposers. Some examples of scavengers include crows, vultures, and possums.
Detritivores are animals that feed on detritus—the dead and decaying remains of plants and animals, as well as organic waste. As they eat, they physically break the material into smaller pieces. The waste they produce returns nutrients to the soil. Detritivores are usually invertebrates and include earthworms, pill bugs, millipedes, and termites.
Fungi (molds, mildews, and mushrooms) and microscopic organisms (those that are too small to see with the human eye), like bacteria, release special substances called enzymes that break down dead material around them rather than by consuming them physically. From this process, they absorb the nutrients they need to survive.
Together, all of these organisms help recycle nutrients back into the ecosystem.
Termite in Rotting Log
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Decomposers play an important role in every food chain! A food chain demonstrates the transfer of nutrients and energy (in the form of food) from one organism to another. The sun gives energy to producers (plants) which are then eaten by consumers (animals). The energy is passed from the producers to the consumers. Each organism in the chain is linked together based on what it eats. When consumers die or produce waste, decomposers take some of that energy and return it back to the soil for plants to use once again.
Food Chain
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Decomposers play an important role in the Nitrogen Cycle and the Carbon Cycle. In these cycles, carbon and nitrogen are taken from the atmosphere and soil in their elemental (pure) forms and turned into more complex molecules such as sugar, energy in the form of ATP, and amino acids which combine to form proteins.
This transition happens when plants go through the processes of photosynthesis and nitrogen fixation. Some of these complex molecules along with the carbon and nitrogen in them are passed along the food chain.
Decomposers take these complex molecules and break them down into simpler forms. The carbon and nitrogen are released back into the atmosphere and soil for plants and animals to use again!
Without decomposers, these cycles would end, and our air and soil would become unusable.
Carbon Cycle
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Nitrogen Cycle
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Decomposers can be found in almost every habitat on Earth. Wherever plants and animals live, eventually something dies or produces waste—and decomposers are there to break it down. Different decomposers thrive in different environments, depending on things like moisture, temperature, food, oxygen, and shelter.
In a Habitat Learning Lab, decomposers can be found easily in the outdoor learning stations listed below.
Rotting logs in a log decomposition station represent what happens on a larger scale in real forests.
When a tree falls, it remains there as decomposers slowly consume it and return the nutrients to the soil by breaking down complex molecules into simple carbon, nitrogen, and other minerals that living plants can use.
A forest is considered a major habitat, and the fallen log is considered a microhabitat (a smaller habitat within a major habitat). The log provides food, water, shelter, and places to raise young for animals living around it. Producers, consumers, and decomposers can live in a fallen log.
Beetles in Rotting Log
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In a compost bin or pile, bacteria (decomposers) use oxygen and heat to break down organic material such as leaves, sticks, grass clippings, and dead flowers.
Finished compost is dark, spongy, and full of nutrients. It can be spread into gardens to fertilize plants, help break up the soil so that it can retain water, and helps plants grow faster and bigger.
Compost Pile
Flickr – Alan Levine
Vermicomposting is the method of using earthworms to speed up the process of composting in a compost bin or pile.
The worms consume the compost materials and turn them into worm castings (poop), which is more useful. These castings can be spread in gardens to fertilize plants, help break up the soil so that it can retain water, and help plants grow bigger.
This system shows how important worms are to the health of our ecosystem. Worms help break down organic matter into things that the plants in our ecosystem can use. They also create nutrient-filled soil with their castings and break up the soil with their tunnels so that soil can hold more water.
Vermicompost
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Do not add:
Safe to add:
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#1: The mushroom we see above the ground is the reproductive structure, or fruiting body, of some fungi. Much of the fungus is made up of tiny threads called hyphae that grow through soil or dead material. Those hyphae connect and together form an interconnected web called mycelium.
#2: A dead tree can become a whole ecosystem. Once a tree dies, fungi, bacteria, insects, worms, birds, and other organisms may use it for food or shelter. As decomposers slowly break the tree apart, sometimes taking years, the dead wood becomes part of the soil.
#3: A teaspoon of healthy soil can contain millions or even billions of microorganisms, including bacteria and fungi.
#4: Certain fungi release acids and other chemicals that help them take minerals from rocks. Fungi aren’t limited to decomposing dead plants and animals!
Illustration of Mushroom Fruiting Body Aboveground
and Mycelium Underground
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#5: There are decomposers living in places where humans couldn’t survive. Some microorganisms can break down organic material in extremely hot, cold, salty, or acidic environments. Some decomposers can even survive and break down organic material in places with little or no oxygen, such as deep mud, swamps, and landfills. These organisms are called anaerobic decomposers. These conditions slow down the process of decomposition, so some materials can remain in landfills for a surprisingly long time. This is why it’s important that we reduce, reuse, and recycle!
#6: Termites can’t digest wood completely on their own. Microorganisms living inside their digestive systems help break down parts of the wood they eat.
Slow Decomposition at Landfill
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#7: As microorganisms break down organic material, they can produce gases and chemicals with strong odors. That “rotten” smell is actually evidence that decomposition is happening!
#8: A large compost pile can become surprisingly warm because microorganisms release heat as they break down organic material. A well-functioning compost pile can become much warmer than the surrounding air.
#9: Decomposition happens inside living animals, too. Microorganisms living in the digestive systems of animals such as cows, termites, and humans help break down food. These organisms aren’t decomposing a dead animal, but they perform similar jobs by breaking complex materials into simpler substances.
High Temperature of Compost Pile
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