NATURAL DEGENERATE MEDITERRANEAN FORESTS - WHICH FUTURE - THE EXAMPLES OF THE HOLM OAK (QUERCUS-ILEX L) AND CHESTNUT (CASTANEA-SATIVA MILL) COPPICE STANDS

Primarily derived from the Quercus pubescens forest destroyed by overexploitation, the Quercus ilex and Castanea sativa coppice stands are two of the most widespread biocoenoses in the European Mediterranean area. Two of the questions we sought to answer were (i) in the case where the same disturbance persists, whether these coppice stands reach a state of “equilibrium” based on auto-succession or they continue to change, and (ii) in the case where disturbance stops, whether the present dominant species (Q. ilex or C. sativa) continues to be dominant (high resilience) or an other species (Q. pubescens ?) could replace it. A third case exists, i.e. a change of the “disturbance” in order to obtain a “sustainable” development, but, in that case, biological or socio-economical criteria must be defined. In order to highlight the first stages of these possible changes, germination abilities of these species were studied and compared. For Q. ilex coppice stands, it can be said that there would appear to be a partial allelopathic inhibition of Q. ilex germination, to which Q. pubescens is less sensitive. For C. sativa, this phenomenon was not found. We also briefly discuss the main characteristics of a programme which tests some biological criteria for a sustainable development.