Comparing the effects of litter quantity and quality on soil biota structure and functioning: Application to a cultivated soil in Northern France

Doubling the quantity of added litter caused deep changes in the composition of detritivorous fauna by promoting the largest-sized group of detritivores (anecic earthworms) to the detriment of the smaller-sized groups (Collembola), which in turn led to higher litter consumption for a similar amount of soil biota biomass and hydrolytic enzyme activities after seven months of decomposition. In contrast, low litter quality stimulated the fungal energy channel, with an increase in the relative proportion of fungi, fungal feeding nematodes and euedaphic and hemiedaphic collembolans. This food web was characterized by a shift towards nitrogen acquisition that decreased the C:N ratio of enzymatic activities. Litter management is a central factor to consider for influencing ecosystem services such as soil fertility and nutrient cycling through the promotion of specific functional groups in soil.