In which ecosystem, a larger fraction of energy flows through detritus food chain (DFC) than through grazing food chain (GFC)?

Terrestrial ecosystem

The correct answer is Option (4) -Terrestrial ecosystem

In an aquatic ecosystem, GFC is the major conduit for energy flow. As against this, in a terrestrial ecosystem, a much larger fraction of energy flows through the detritus food chain than through the GFC.

In terrestrial ecosystems, a larger fraction of energy flows through the detritus food chain compared to grazing food chain (GFC). This is because terrestrial ecosystems often have a higher abundance of detritus or dead organic matter, such as leaf litter, fallen branches, and decaying plant material.

In terrestrial ecosystems, detritus can accumulate on the forest floor, in soil, or in other terrestrial habitats. This provides a substantial source of organic matter for decomposers, such as fungi and bacteria, to break down and derive energy from. These decomposers play a vital role in the detritus food chain by decomposing dead organic material and releasing nutrients back into the ecosystem.

The detritus food chain in terrestrial ecosystems involves the breakdown of detritus by decomposers, followed by the consumption of the decomposers by detritivores or other organisms that feed on detritus. This transfer of energy from detritus to higher trophic levels contributes to a significant portion of the energy flow in terrestrial ecosystems.