Abstract
The relationship between erosion and biodiversity is reciprocal. Soil
organisms can both reduce soil loss, by improving porosity, and increase
it, by diminishing soil stability as a result of their mixing
activities. Simultaneously, soil runoff has ecological impacts on
belowground communities. Despite these obvious interactions, soil
erosion models do not consider biodiversity in their estimates and soil
ecology has poorly investigated the effects of erosion. In order to
start filling in these knowledge gaps, a novel biological factor was
developed and introduced, for the first time, into a well-known soil
erosion model (the revised universal soil loss equation, RUSLE).
Furthermore, insights to advance soil erosion ecology were proposed.
Thanks to available data on both soil erosion (Panagos et al., 2015) and
earthworm diversity (Rutgers et al., 2016), an “earthworm factor” was
generated and applied to produce the first maps of a modified soil
erodibility. The incorporation of “earthworm factor” reduces soil
erodibility and as a consequence soil erosion. On the other hand, also
the erosive events affect the soil-living communities. Potential
consequences of soil erosion on soil life were also identified:
migration, invasion, violence, defence, rebuilding and functional
effects were described. The results showed how new estimates of soil
loss can be produced by adding biological factors to soil erosion
models. The earthworm factor represents the first step towards the
inclusion of a wider biological factor, which takes into account the
whole soil-living community, into erosion modelling. Fostering the
development of soil erosion ecology for better understanding the
reciprocal effects of erosion on soil life, will contribute towards this
achievement. The increasing availability of large-scale data on soil
biodiversity distribution opens up the possibility of incorporating a
biological component into bio-physical models such as the soil erosion
one. The model integration between the soil ecologists and soil erosion
modellers is key point for identifying the interactions between soil
organisms and soil loss