The compost and vermicompost treatments were clearly separated from the mineral treatment along the first axis, which explained 57% of the total variance. The compost and vermicompost treatments were characterized by higher C and N, higher pH and CEC, and lower available P, NH4+ and NO3− than the mineral treatment. The compost and vermicompost treatments were separated from each other along the second axis of the PCA, which explained 23% of the total variance. Soils amended with compost were more acidic (lower pHH2OpHH2O and pHKCl) and had lower NH4+ and higher Pavailable contents. This could be partially due to the small quantity of phosphate and urea in the compost and vermicompost, respectively (Table 1). Earthworms did not influence the chemical properties of the soil in the mineral or vermicompost treatments (except CEC which decreased in the presence of earthworms for the vermicompost treatment). However, the PCA differentiated the compost treatment in the presence or absence of earthworms, mainly because of the lower C content in soils inoculated with earthworms.