Soil loss on forests in MT. Etna Natural Park (Italy)

Poli Marchese Emilia, Grillo M., Caruso F., Margani I.

DACPA, Sez. Biologia ed Ecologia vegetale, Università di Catania.

Soil erosion is a serious problem, particularly in the Mediterranean region, where a long period of land use has increased the phenomenon. We have studied this problem in the Mt. Etna natural Park for some years. In two previous studies we showed the relationship between soil erosion and vegetation. The aim here is to show the soil loss in some Etnean forest areas.

In 33 areas selected within Fagus sylvatica forests and Castanea sativa, located at 1400-1700 m a.s.l., 115 relevés were made and some soil loss data at the tree foot were collected. The soil loss index (S.L.I.) was calculated on the basis of the surface soil loss.

The results show that the S.L.I. reaches the highest value (6,68) at the foot of a 20m high Fagus sylvatica tree, with a diameter of about 30 cm, located on a 30° slope with E-SE exposure.

The communities where the S.L.I. reaches the highest value (4,01 and 3,46) are 18 m high beech forests, with a canopy cover of 90%, located on slopes of 40-45°, with NE and S-SW exposure.

These results were related to human activities that favour and accelerate soil erosion. In forests located in sites with high slope values (>40°), but with little human disturbance, the S.L.I. is absent or very low (e.g.0,02).