The Bizarre Role of Soil Animals in the Decomposition of Dead Leaves

Abstract

When plant leaves die, they fall and accumulate on the soil where an important process occurs: they decompose. Decomposition is essential for recycling nutrients and returning them to the soil. It is mainly done by an army of creatures called microbes, invisible to the naked eye, that slowly make the dead leaves rot. But larger creatures, like millipede and snails, also eat dead leaves. These large creatures do not digest these leaves very well and return most of the leaf matter to the soil as poo, which is further decomposed by microbes. Does this transformation of dead leaves into poo affect the recycling process? By collecting poo from many soil animals feeding on dead leaves, we found that they decomposed faster than intact dead leaves. This means that soil animals help the decomposition of dead leaves, not by digesting them, but by transforming them into poo.