Competition, mortality, and development of spatial patterns in two Cantabrian populations of <i>Fagus sylvatica</i> L. (Fagaceae)

Abstract

In this paper the spatial patterns of size and mortality of European beech ( Fagus sylvatica L.) were analy sed in two deciduous forest plots of Northern Spain. ?i general terms, radial growth of F. sylvatica yields a direct relationship with size and an inverse relation with intraspecific competition while tree mortality seems be related to intraspecific competition. In the overall even-aged population, a lack of a recognisable structure in tree-size distribution, a small-scale regularity of survivors, and a regular pattern of dominant trees was noticed. This is a consequence of intense intraspecific competition at local level. In the old-growth plot, the wide repulsion between small and large beeches yields a specific spatial structure in tree-size distribution, showing even-sized groups of trees in different stages. Mortality in this plot occurs mainly within the dense group of small trees, which produces a broad regular pattern among the live beech trees. The random spatial pattern of dominant beeches seems to be characteristic of old-growth forests and could be a consequence of either self-thinning processes or exogenous factors.