LEAF-LITTER DECOMPOSITION DYNAMICS IN SOME MEDITERRANEAN DECIDUOUS OAKS

Leaf litter decomposition of both Quercms pyrenaica and Q. lanuginosa oaks (the former from the Province of Salamanca, Spain, the latter from the Montpellier hinterland, France) was studied over three years. Leaf mass losses amounted 32-38%, 42-53% and 53-65%, respectively, after one, two and three years of decomposition. An experiment on oak leaf exchange showed that leaf decomposition progresses faster at the French site as a consequence of climatic factors. It is concluded that environmental factors, especially the moisture level in Mediterranean areas, characterized by very dry summers, play an important role in leaf decomposition, mainly because of their direct effect on the microbial and mesofaunistic activity of the soil.