PS 24-64
Influence of Eucalyptus urophylla plantations on the ecological environment
Despite decades of research and thousands of studies on the plantation of Eucalyptus in many countries, the debate on its impacts on ecological environment remains obscure. On a bare land in a forest park located in south part of Guangdong province, south China, we established five types of plantations, including two types of Eucalyptus urophylla plantations (ecological public welfare forest plantations and commercial forest plantations) and other three types of ecological public welfare forest plantations, Pinus elliottii, Acacia mangium, Cunninghamia lanceolata plantations, to monitor the dynamics of environmental conditions and species richness. During the three years period, seasonal variation of the soil physicochemical properties (organic matter, nitrogen, phosphorus, potassium，pH, moisture, volume-weight and porosity) on each forest stand were measured. Furthermore, the numbers of the understory plant species were also recorded.
Results/Conclusions: The soil on Eucalyptus urophylla ecological public welfare forest plantations was poorer than that on both Acacia mangium and Cunninghamia lanceolata plantations, but slightly richer than that on Pinus elliottii plantations. The number of understory plant species in Eucalyptus urophylla public welfare forest plantations is also lower than that in other three types of public welfare forest plantations. Both Eucalyptus urophylla ecological public welfare forest plantations and commercial forest plantations have the similar soil chemical properties, but a significant difference in soil physical properties. Comparing with the latter, the former has higher species richness in the understory. We concluded that Eucalyptus urophylla plantations have a negative effect on the ecological environment.