Accumulation of organic matter and nutrients in the surface soil of a young silvopastoral system in Greece

Organic matter and N, P, Ca, Mg, K and Na accumulation in two successive soil layers (0-20 cm and 20-40 cm depth) were investigated, eight years following the establishment of a silvopastoral system of sycamore (Acer pseudoplatanus) and Scots pine (Pinus sylvestris) in northern Greece. The experimental layout was a split-split plot design with three replications and included: three under-torey treatments (grass, legume and control), two tree species (sycamore and Scots pine) and two tree spacings (2.5 x 2.5 m and 3.5 x 3.5 m). Organic matter and N, P, Ca, Mg, K and Na accumulation in the surface soil were not influenced significantly either by the understorey vegetation nor by the tree species planted or by tree spacing.