What are Detritivores (aka ‘decomposers’)?

Nature relies upon the cycling of matter (between biotic and abiotic forms) in order to be utilized again in new life. For example, a leaf decays upon the forest floor, and of course, these valuable elements that make up the leaf, must be brought back into the ecosystem and utilized. We need a “spoon”, metaphorically speaking, to break things down and stir things up to make them usable again. Without decomposers, we’d run out of the basic building blocks quickly, and there’d be nothing to break down the waste!

Well, we owe the “stirring of life stuff” to a class of organisms on our planet called, “detritivores” or, “decomposers”, or as some fancy pants people like to say in science, “saprophages”. Detritivores can appear in macroscopic and microscopic varieties and make up an extremely important part of the trophic system (how organisms fit within a hierarchy of consumption).

Some of the common detritivores we see often are earth worms, fungi, and potato bugs [which ironically enough are crustaceans and more closely related to shrimp than insects] (arkive.org).

worm

Earthworms help break down organic matter while aerating the soil and creating drainages for water and gas exchange. Additionally, earth worms help facilitate the growth of fungus and bacteria in the soil (positively encouraging more decomposers to join the parade) by leaving behind waste products that they are can consume.

woodlouse

Also known as a ‘Potato Bug’ or a ‘Woodlouse’, these crustacean animals are more closely related to shrimp than insects. These animals feed on decayed matter breaking them down further.

Modified by CombineZP

Without fungus the world would be very different. A champion detritivore and an attraction for many hobbyists and recreationalists, fungus helps break down complex lignin plant compounds that other detritivores cannot handle. Additionally, fungus helps mobilize nutrients and water to aid nearby plants with hungry root cells.

Life’s Big Stirring Rod

Without decomposers, things would only have mechanical methods to break down, like wind and water. Small, tiny elements that are crucial for plant or animal development might take hundreds of years to become accessible. With the help of macrodecomposers like those above, and the billions of bacteria (microscopic) that aid in the process, the mobilization of nutrients and elements moves much faster. Some research has even been done to note the differences in plant decomposition rates with the evolutionary introduction of fungus, about 300-500mya, noting a mass acceleration in decomposition rates. Simply stated, stuff probably breaks down faster and more quickly than ever before, thanks to the diverse branch of decomposers in our biosphere.

Biogeochemical Cycling and the Trophic System

This movement of stuff in science is also known as, biogeochemical cycling, that is, the cycling of biological, geological and chemical materials within any given biosphere or ecosystem. AKA, the combination of all of these various decomposers moves elements between the lithosphere and biosphere, and bridges the abiotic and biotic world. This breaking down at the most basic of levels allows nutrients and matter to move up the trophic system to larger life forms. All of the vitamins and minerals and amino acids that you rely upon in your daily essential dietary needs, are derived from the hard work of decomposers and detritivores, allowing these elements to move in and out of living systems, and then concentrate in their tissues by means of bioaccumulation or biomagnification.

Conclusion

Without decomposers, we wouldn’t have much at all. They are the basis for new life, and often overlooked in our study of biology and ecosystem well-being. A good solid base of decomposers is crucial for biogeochemical cycling to take place, and to create things like “healthy soils” or your most basic backyard compost bin. The more decomposers actively working in an ecosystem, the faster things are moving biochemically speaking, thus aiding in more productivity within organisms – as now more things are accessible – and in some cases the addition or reduction of detritivore populations may affect other organism relationships as well. For example, if we took a soil that was sterile, lacking decomposers, and added some, what might we see happen?

Let us all take a deep breath and give a round of applause for the decomposers of our world. You wouldn’t be you, literally, without them!