Abstract:

Species composition and diversity of the 4 main secondary forest types were studied in this paper. The results showed: 1) A total of 378 plant species from 215 genera in 78 families were found in this region during the observations in two growing seasons. In the 37 sample plots that were set up in the second growing season, we found 183 plant species belonging to 123 genera in 58 families, among which, 34 arbor specieses, 33 shrub specieses and 116 herb specieses. Besides several common tree species, such as Quercus mongolica, Betula costata, Juglans mandshurica, Fraxinus mandshurica and Fraxinus rhynchophylla, Acer mono, Acer pseudo-sieboldianum, Euonymus alatus var. pubescens, Rubus crataegifolius, Meehania urticifolia, Cardamine leucantha, Carex siderosticta, Dryopteris crassirhizoma and Adiantum pedatum were the most frequently appeared species in the secondary forests. 2) To the plant communities of secondary forests in the montane regions of eastern Liaoning Province, China, the minimum sampling area for diversity investigation was 16 m×16 m and 20 m×20 m which contained 80% and 90% of all the plant species, respectively. 3) The values of Shannon-Weiner index in this region were between 3.200 and 3.600. The maximum value appeared in the mixed broad-leaved forests with Shannon-Wiener index of 3.567. Diversity of arbor layer, shrub layer and herb layer among the four major forest types exhibited different patterns, I.e., the diversity of arbor layer was lower than those of shrub layer and herb layer in most types.

Key words: montane regions of eastern Liaoning Province, secondary forests, species composition, diversity