By Linda Ray
Decomposers and detritivores play a crucial role in food webs and ecosystems on our planet. Think about a world that did not have a way of breaking down dead organic matter. It wouldn’t take long before decaying matter covered the earth and prevented life as we know it from surviving. Thus, decomposers (including detritivores) have their own niche in food webs and without them there would be no functioning ecosystems.
Who are the decomposers and detritivores? Their names say it all. Decomposers, such as fungi and bacteria, break down the cells of dead plants and animals into simpler compounds through chemical reactions.
They do this by secreting digestive enzymes into decaying materials. Detritivores, such as millepedes, termites, and beetles, are organisms that consume organic waste (also called detritus) and produce nutrient rich materials from their bodies. Their purpose is to eat and survive but the glorious result is that dead organic matter is recycled and when clay is added, this produces humus. Humus is rich in nutrients and minerals and helps soil be porous for plants and algae to grow, which are the primary producers of food on earth.
Detritivores, such as millepedes, termites, and beetles, are organisms that consume organic waste (also called detritus) and produce nutrient rich materials from their bodies.
Decomposers and detritivores are fascinating in the roles they play in the balance of the natural world. Their work is visible everywhere when you take a look. For instance, compost piles (we have all seen the mycelium), composting toilets, last season’s leaves, dead tree trunks and branches, and cow pies are just a few examples. Taking a walk in the woods will oftentimes suffice for a view into this world. Find a dead tree and inspect the bark. Are there round or oval holes? If so, peeling back the bark may reveal the tracks of wood boring beetle larvae. It is said that if there are enough round headed wood boring beetle larvae eating, their chewing is audible. Is there a pile of sawdust? This can mean termites are present.
When they breakdown cellulose, their waste (frass) becomes termite sawdust. If there is a smell of cherries in the dead tree, that could indicate millipedes are close by. The cherry smell of cyanide is their defense and they don’t like their home being disturbed. Digging around the dead tree, there will most likely be earthworms adding their waste nutrients to the soil. A dead tree is a whole world and evidence of recycling in motion.
Sources:
Entomology for the Naturalist, Clemson Cooperative Extension
Solomon, Steve, 2013, the intelligent gardener. BC, Canada: New Society Publishers.
Photo Credit:
Lairich Rig / Patterns on wood caused by tunneling beetles / CC BY-SA 2.0