Abstract. Relationships between plant form, plant function, and environmental factors are analyzed in order to test the efficiency of growth form attributes and phenomorphology for studying vegetation on a regional scale. Examples of sclerophyllous evergreen coppices with Quercus ilex in the mediterranean climate of southern France are examined. The results for three growth form attributes (renewal bud location, leaf consistency, leaf size) and some environmental factors show that these criteria are efficient along a gradient of increasing stress. Concerning phenomorphology, some trends along the main environmental gradient become evident, but these results should be confirmed with descriptions of more species. It is suggested that man's ancient, very strong influence upon these ecosystems could explain some results showing that growth form distribution does not fit the pattern of variation in environmental factors.
Allozymes at a maximum of eight loci were used to analyse the spatial patterns of genetic variation in 1942 hoim oak trees (Quercus ilex L.) from 57 provenances distributed in the six main disjunct areas of the species distribution area. Polymorphism and genetic diversity were high except in the six marginal populations growing in various locations under unfavourable climatic conditions. Ten per cent of the total genetic diversity (H = 0.262) was accounted for by among-population variation. In this long-lived species, the effect of geographical discontinuities on gene flow restriction was shown by the occurrence of: (i) numerous rare alleles limited to a single disjunct region; and (ii) allele frequency variation among the disjunct regions for four alleles. This result was obtained by comparing spatial autocorrelograms from the 57 populations of the entire distribution area and from the 31 populations of the Mediterranean continental region which constitutes the largest continuous area in that distribution. Life history traits (e.g. long life span and high outcrossing rate) and past changes in climate and geographical continuity are assumed to be the main factors responsible for the present genetic variation patterns observed in the species.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.