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How does a grazing food chain differ from a detritus food chain?

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Diagram illustrating Earth's environmental spheres, with labeled sections showing the geosphere (land and crust), biosphere (living things), atmosphere (air), and hydrosphere (water), each extending vertically from the Earth's surface. — Biosphere Earth's environment includes the atmosphere, the hydrosphere, the lithosphere, and the biosphere.

In ecology, the primary difference between a grazing food chain and a detritus food chain lies in the source of energy that initiates the sequence.1

Grazing Food Chain: This pathway begins with living plants (primary producers). The energy stored by these plants through photosynthesis is transferred to primary consumers, such as herbivores, which are then consumed by carnivores at higher trophic levels.12
Detritus Food Chain: This pathway begins with detritus—dead organic matter such as fallen leaves, animal remains, and waste products. Microorganisms, such as bacteria and fungi, break down this material. This microorganism-rich detritus is then consumed by invertebrates, which may subsequently be eaten by vertebrates.314

Both pathways are essential to the energy budget of an ecosystem, as they represent the two primary ways organic matter and nutrients move through the biosphere.1