Regular research paper

Ecological groups of vascular plant species in the herb layer of the pine forests of Northern and Central Europe

Ewa Roo-Zielińska

Institute of Geography and Spatial Organization, Polish Academy of Sciences, 00-818 Warszawa, Twarda 51/55, e.roo@twarda.pan.pl

Abstract: 

     The species of vascular plants of the herb layer, were studied on ten forest sites representing pine forests of the alliance Dicrano-Pinion. These sites are  located along the

N-S transect in Northern and Central Europe, between 50^o28’ and 70^o09’ N – in Norway (NO1), Finland (FN1, FN2, FN3), Estonia (ES1), Latvia (LT1), Lithuania (LI1),  and Poland (PL1, PL2, PL3).  The relation was determined  between the geographical location of these forests and the proportion in  total species number and cover of the plants in  the herb layer with known ecological, habitat and climatic requirements for  light (L) and temperature (T) and soil requirements for moisture (F), acidity (R), and content of nitrogen (N). The indication method was applied using  the species scale of Ellenberg et al. (1991), indicating  the climatic and habitat requirements of the plant species on the basis of the values of the L, T, F, R and N  in the macroclimatic gradient. The species  which behave in a similar manner with respect to the habitat factors mentioned were clustered into the indicator species groups. The distinct directional changes of the share of these groups along the North-South transect were observed: 1) gradual appearance of the species characteristic for the moderately warm areas; 2) decrease of the share of the hygrophilous and acidophilous species.

Key words: plant ecological groups, Ellenberg indication method, temperature, moisture, acidity, nitrogen content, habitat conditions