What is the Definition of Detritivore?
Detritivores is a heterotrophic organism that gets its nutrition by feeding on detritus. Detritus is the organic matter made up of dead plant and animal material. Detritivores can also feed through coprophagy, which is a feeding strategy that involves consuming feces.
Detritivores are often invertebrate insects such as mites, beetles, butterflies, and flies; Mollusks such as snails and slugs; or ground-dwelling earthworms, millipedes and wood lice. Examples of detritivores in marine environments are crustaceans such as crabs and lobsters, echinoderms such as starfish or sea cucumbers.
Many of these marine detritivores occupy a niche similar to that of terrestrial soil dwellers who live on or within the seabed known as benthos. These organisms are often referred to as “bottom feeders”. Alternatively, stationary polychaete worms, barnacles, and some corals in aquatic ecosystems obtain their energy from filter-feeding on floating organic waste known as “sea snow”.
The terms “detritivore” and “decomposer” differ in their meaning; Although the words are often used interchangeably, technically detritivores are a branch of decomposers. It is useful to note that, unlike detritivores, true decomposers like fungi, bacteria, or protists use saprotrophic feeding, where they ingest nutrients through extracellular digestion rather than orally.
However, similarities can be drawn between detritivores and scavengers. While both of these feeding strategies involve consuming dead plant and animal material, scavengers tend to feed on a larger scale than detritivores, which specialize in carrion and feces.
What is Function of Detritivores?
Detritivores and decomposers help breakdown all of the dead and decaying material in any ecosystem. In this way, they play an important role in the nutrient cycle and are an integral part of most biogeochemical cycles such as the carbon cycle, the nitrogen cycle, and the phosphorus cycle.
Detritivores feed on material from primary producers as well as herbivores and carnivores and are therefore present at all trophic levels of an ecosystem. Detritivores not only consume energy from other organisms but are also often eaten by secondary consumers and are therefore an essential part of the ecosystem’s energy cycle.
The recycling process is not only an important part of the decomposition process but also the removal of dead material to stop the spread of disease. In addition, detritivores that live in the soil, e.g. Earthworms, aerate and mix the soil with their movement, which is important for the growth of plants.
The Decomposition Cycle
Detritus is made up of particulate organic material (POM), which is formed from tissues that are deposited when plants and animals die or when skin or antlers are sloughed off, as well as feces and microorganisms. The colonies of microorganisms in the detritus add to its nutritional value.
In terrestrial environments, detritus can be present as humus (the dead material mixed with soil) or as leaf litter. In water bodies, the detritus is hung up as “sea snow” which eventually falls to the seafloor. All of this material contains energy as well as the nutrients that were present in the waste material and in the bodies of the deceased.
These substances are valuable raw materials in all energy and nutrient cycles, although the minerals and compounds have to be made available through physical decomposition and biochemical conversion of the material through decomposition or remineralization.
Detritivores feed on the larger particulate material in the early stages of decomposition, fragmenting the material into smaller pieces. The fragmentation process increases the surface available for attack by bacteria and other microorganisms and thus supports and accelerates the decomposition process.
Digestion by the detritivores also breaks down some carbohydrates, proteins, and lipids present in the detritus into simpler substances. The water-soluble nutrients produced from this leach into the soil and increase the soil mineral content. At the same time, the detritivores are extracting nutrition for their own life cycles, and in doing so, contribute their biomass to the food chain when they are eaten by consumers.
Throughout the process, decomposers such as fungi and other microorganisms, also known as saprophytes, perform a true decomposition, using chemical compounds and digestive enzymes to convert material excreted by the detritivores into simpler substances like inorganic carbon.
These cyclic substances are essential to all life, for example, inorganic carbon released from the respiration of decomposers is taken in by plants and is used to perform photosynthesis. Successive decomposition of the modified organic matter results in humification – the formation of humus a type of soil with high mineral content and stability.
Examples of Detritivore
Worms are one of the most important soil dwellers. They consume a lot of organic matter and soil and are present in all layers of their substrate. Epigeic worms live on the surface, while endogeic worms live in the upper soil layer.
These two types of worms usually feed on dead grass, fallen leaves, and other bio-organic materials such as fungi, algae, and the microorganisms that also feed on these substances. Anecic worms live deep in the ground and are mainly composed of raw soil, although it is rich in bacteria, fungi, and algae.
Worms ingest food through the mouth and “suck” it into the digestive system with muscle action. As the material enters its “gizzard” through its digestive system, it is subject to digestive enzymes as well as the grinding action that results from the presence of sand and sand in the soil.
A “cast” is drawn out from the back of the worm. The cast is basically a more processed version of the receiving soil, with smaller nutrient particles available for decomposition by other organisms. The presence of the microorganisms in the detritus ingested by the worms also accelerates the decomposition process during digestion.
Worms are constantly on the move because of their feeding strategy. This movement helps mix and aerate the soil, which also improves water uptake and nutrient transport, and allows plants to grow more efficiently.
Springtails are wingless arthropods that live primarily as detritivores. They are most common in hardwood and other habitats where there is rotting material like moss, grass, and deadwood.
Most springtails are vegetarian and feed on fungal mycelium, vegetation, lichen, pollen, and algae, although some species have been found to feed on rotting animal matter such as dead earthworms and flies.
They are very adaptable, have a rapid rate of reproduction, and a diverse range of habitats and diets. They colonize in large numbers and are one of the most numerous macroscopic animals. A single square meter of the floor can contain around 100,000 springtails! They can withstand a range of temperatures, from warm habitats to frozen snow. However, they are generally prone to dehydration, so opt for humid environments.
Benefits of Springtails
Springtails have a large effect on the rate of detritus decomposition, and studies have found that the removal of springtails significantly reduces the rate of leaf litter decomposition. They are important in controlling fungal diseases because they consume spores and mycelium and can remove pathogens.
They can also be used to test the toxicology of the soil. They are very sensitive to pollutants and can therefore be used as bioindicators for soil quality