Effects of population density of competitive trees on growth and mortality rates of pioneer tree species in the suburban secondary forest

For the purpose of obtaining ecological information necessary for vegetation management after clear-cutting, mortality rates and tree height growths pioneer species, Mallotus japonicus, Zanthoxylum ailanthoides, Clerodendrum trichotomum Aralia elata were investigated in a suburban secondary forest. In addition, relationships between growth characteristics these four species initial size, surrounding competitive density or site environment examined. As result, rate was highest A. at 16.4%/year, followed by C. 10.1%/year M. japonicus 8.3%/year. On other hand, it lowest value 1.2%/year Z. ailanthoides. The mean relative 0.139 cm/cm/year next 0.089 0.056 japonicus. had 0.035 cm/cm/year. under same conditions class soil moisture content habitat, tended to decrease as competing trees increased. effects habitat on not clear species.