Study on species diversity of Eucalyptus spp., Pinus massoniana and Pinus elliottii plantations

The biodiversity characteristics of different types of forest were studied in Guangxi Shatang State Forest Farm based on the biological community survey about three kinds of pure plantations including Eucalyptus spp., Pinus massoniana and Pinus elliottii. The results indicated that there was no significant difference among different types of stands in species diversity index, and the species type and quantity in Eucalyptus plantation depended on those of original vegetation and biology to a great extent. The Shannon-Weiner diversity index, Simpson dominance index and Margalef richness index of the herb layer were generally lower than those of the shrub layer, the layering of herb layer and shrub layer in Eucalyptus plantation was not obvious, and the species richness index and diversity index of the shrub layer were higher than those of the herb layer. Repeated planting could decrease the diversity index of the shrub layer, but increase that of the herb layer.