SEARCH FOR FACTORS MAINTAINING TERRICOLOU S BRYOFLORA RICHNESS IN ISOLATED HABITATS .2. COMPARISON BETWEEN THE SCLEROPHYLLOUS OAK GROVES OFTHE OCCIDENTAL BORDER OF THE MASSIF DES MAURES (VAR, FRANCE) AND THEIR INTERFACES WITH THE VINEYARD (IN FRENCH)

Processing (FAC) of 74 bryophytoecological releves from 6 forest struc tures with Quercus ilex or Quercus suber, isolated within the vineyard near Pierrefeu-du-Var (siliceous substratum), and the outlying contac t zones : Prunus spinosa - Rubus or Cistus scrubs (I), bare soils or l awns often rich in ruderal species (i). The confrontation of the bryof loristical and the station data shows that ambient humidity and substr atum richness in total nitrogen play an important role in the differen ciation of terricolous bryophyte communities. Two forest sets, one hum id and rich in nitrogen of organic origin (ubac of Defens du Becasson : surface = 77617 m(2), scrub-layer dense), the other dry and poor in that element (isolates and hedges with a surface less than or equal to 13115 m(2), scrub-layer absent) have been defined whereas a third, ve ry xeric set, groups nearly all releves from the contact zone i, where supply in nitrate fertilizer may be important.