Essai de synthèse sur la dynamique actuelle des châtaigneraies cévenoles et ses conséquences sur la diversité végétale

摘要: Abstract The present vegetation of the Cevennes mountains (southern France) dominated by sweet chestnut (Castanea sativa) is an outcome uninterrupted and frequently intense human influence existing since millennia. It very different from deciduous Downy oak (Quercus pubescens) forest which occupied area at end last glaciation, during a period when climate was quite similar to day conditions in this subhumid, mid-altitude Mediterranean bioregion. Since impact has been drastically decreasing for half century, but especially recent years, possible trends can be envisioned formerly chestnut-dominated built on steep slopes terraces. Based experimental results seed germination studies as well analysis plant species diversity trends, we propose some trajectories eventual ‘threshold crossings’ landscapes region suffering rural exodus agricultural abandonment....