Abstract:
ObjectiveThe aim of this study was to provide a basis for the growth, protection and management of Tilia amurensis secondary forest by analyzing the quantity and spatial structure characteristics of standing live and dead trees and exploring the growth state, succession process and the main causes of standing dead trees under two disturbance modes (non-cutting and selective cutting).
MethodThe research was conducted by analyzing the species composition, diameter structure, height structure and spatial structure of standing live and dead trees.
Result(1) Tilia amurensis, Acer mono, as well as other dominant tree species in living trees also had a dominant position in dead trees in selective cutting stand, while only Tilia amurensis was dominate among the living trees and standing dead trees in non-cutting stand, but Acer mono was only dominate in the living trees, and it was rare in dead standing trees. (2) The standing live and dead trees of the small diameter were dominant in all two stands, and the diameter distribution was roughly inverted J type. The height class distribution of living trees was roughly left-skewed distribution in two stands, while the standing dead trees were inverted J type, meanwhile, the small standing dead trees accounted for a large proportion. Therefore, it could be analyzed that the main reason for the formation of dead trees in the two stands was the competition among trees. (3) The trivariate distribution of spatial structure parameters had shown that there were more dominant living trees, which were randomly distributed, highly mixed and dominant in two stands. Whereas, most of the standing dead trees were randomly distributed, in disadvantaged state, and the surrounding trees were all other tree species or only one was the same tree species. (4) The quadrivariate distribution of spatial structure parameters showed that the standing dead trees of the two stands were randomly distributed in general with good mixture of species and obvious size differentiation. There were three or four standing live trees around one standing dead trees in that state.
ConclusionIt further indicates that inter-species competition is the main reason for the formation of standing dead trees. This study analyzed the spatial structure and quantitative characteristics of standing live and dead trees in the secondary forest of Tilia amurensis. Therefore it is not only exploring the formation of dead standing trees in the secondary forest, but also provides a theoretical basis for its protection and management.