Effect of snowpack management on grassland biodiversity and soil properties at a ski resort in the Mediterranean basin (central Italy)

In the Mediterranean basin, the activity of ski resorts below 2000 m of altitude strongly affects grassland ecosystems because of the increasing use of artificial snow (AS). In a representative ski resort of central Apennines (Italy), we studied soil, vegetation and topographic variables of three adjacent grasslands: undisturbed grassland (UG), ski-runs with natural snow and ski-runs with amassed and AS. The winter temperature at the soil surface was colder in the ski-runs (even more in AS) than in the UG with an increase in dissolved organic matter and a biomass decrease. We identified 21 diagnostic species and 14 functional bioindicators linked to soil indicators like surface temperature and moisture. Conversely to observations made in the Alps and in other sites of the Apennines, we did not record any significant decrease in the floristic diversity between ski-runs and UG. Ski-run management aimed to prolong the snowpack duration-induced higher soil humidity and a short vegetative growth that produced a significant shift of the natural structure and composition of the grassland. To preserve key habitats for biodiversity, the construction and extension of ski resorts below the altitude of 2000 m should be avoided in the climatic belt of the Apennines.