At each site, soil samples were taken at two depths (0–10 cm and
10–20 cm) using a plastic spade. Afterwards, soils were air dried at
room temperature until constant weight and sieved to b2 mm using a
nylon sieve. Visible stones and biological debris were removed during
the drying stage. The following soil properties were measured: pH
(according to ISO 10390:1994 procedure), soil organic carbon content
(Org C) (Elemental Analysis, LECO CNH-2000, according to ISO
10694:1995) and particle size distribution (using a Coulter LS230 laser
diffraction particle size analyzer).