The number and distribution of vascular plant species in island forest communities in the northern part of the West Carpathian foothills

Abstract

Phytosociological records were made in 80 stands lying in 50 small woodland islands in the Wierzbanowka valley. The types of communities were distinguished on the basis of numerical classification of records. These were mainly fragments of theTilio-Carpinetum association. For all the stands and for two groups of stands connected with various soils and localized mainly in the eastern or western part of the valley the statistical relationships between ten independent variables were examined (area of record, area of woodland island, its shape, distance to the nearest large woodland, mean distance to the three nearest woodland islands and others) and 10 dependent variables (number of species of trees, shrubs, herbaceous plants, species characteristic of the classesQuerco-Fagetea, Vaccinio-Piceetea, Molinio-Arrhenatheretea, Rudero-Secalietea and others). It was found that the floristic composition of the communities investigated was connected primarily with the isolation of the woodland islands. With increasing isolation the total number of species decreased, as did the number of herbaceous plants and that of herbaceous plants of the classesQuerco-Fagetea andVaccinio-Piceetea, while the number of species of the classesMolinio-Arrhenatheretea andRudero-Secalietea increased. Conditions of the habitat such as the inclination of slopes, shading, and soil fertility were less important.