B. Papp szerk.: Studia Botanica Hungarica 30-31. 1999-2000 (Budapest, 2000)

Papp, Beáta; Rajczy, Miklós: Contributions to the knowledge of bryophytes of the forests along the Fekete-Körös, SE Hungary

and a mid-aged mixed forest. Their bryophyte flora is poorer in species (usually around 11 ) than that of the old, mixed stands. A young black locust stand (yR) forms a third, highly separated cluster by itself (Group III). Its bryoflora consists of only 4 species. The ordination (PCA) was made on the same dataset, i.e. the bryoflora of the studied forest stands (Fig. 3). The first three axes comprise 70.5% of the total variance. The first axis (51.2% of the total variance) does not really separate the forest stands, except the young black locust stand; it has the lowest eigenvalue on this axis, with no neighbours. Axis 2 (Biplot uith a scale factor of 4.34 for variables) PORPLA PSENER HOMTRI BRAPOP m

f BRASAL \ EURANG 1 ANO oM2 f oM1 : LEUSCI ; AN0UIÏ :'oJY|3 ANOATT :IS0AL0 BRARUT ORTDIA FRüDIL

mÖ AMBSEP. oQ4 od3/ : TORPAP"' ; oQ2 oQ1 PLTREP ORTAFF iR2 mR'l -1 II -2 Axis 3 I HYPCUP III BRAUEL Fig. 3. Biplot of PCA analysis, the arrangement of the stands and some selected bryophyte species along the 2nd and 3rd axis, (abbreviations of the stands are the same as in Fig. 2, abbreviations of species are formed by the initial three letters of the genus and species names respectively).