New results of the study of dolomite flax (Linum dolomiticum Borbás)

Abstract

Abstract: Dolomite flax (Linum dolomiticum Borbás) is a strictly protected, endemic, pre-glacial relic plant species of Hungary. The distribution area of this species is extremely narrow: it lives only in a region of one and a half square kilometre in Buda Hills near Pilisszentiván. It has one population only which consists of several stands separated by closed forest. Study of dolomite flax included the following investigations in the last five years: mapping of the total distribution area at a scale of 1 to 200, monitoring of the population size, population genetic and population dynamic studies and phytosociological study of its habitat.
The most important result of the population dynamic study was that ratio of the new and extinct individuals are relatively high (18.0 and 20.2 per cent, respectively), which indicates intensive population dynamic processes. This reproductive dynamism can be estimated very positively from the point of view of survival of the species. The total number of individuals is cca. 42000.
Spatial pattern of the distribution of Linum dolomiticum is not homogenous, i. e. the individuals do not occur randomly on the ground, but usually form groups and patches of size of 0.01-3 m2. Genetic diversity of the population is extremely low. Small genetic differences were detected among the separated stands of the population.
The habitat of dolomite flax encompasses the following vegetation types: open and closed dolomite rocky grasslands, dolomite steppe medow and several transitions and degraded forms of these communities. These grasslands in part belong to the herb layer of Pannonian karst white oak low woods.